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# Locked exchange files after image

I imaged my server to a new hard drive last night (acronis true image server 9), everything went fine.  Shortly after I verified email was again running, data was there, etc I started the backup process (backup exec 10)
I looked in the logs this morning and normally a few files are skipped because in use but I got a lot and they are not the normal files that get locked.
The ones that concern me are the exchange files locked
Here is the log

item C:\Program Files\Exchsrvr\bin\store.fcl in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db000003.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db000008.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db000009.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db00000a.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db00000b.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db00000c.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db00000d.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db00000e.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db00000f.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db000010.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db000011.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db000012.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db000013.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db000014.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db000015.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db000016.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db000017.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db000018.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db000019.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db00001a.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db00001b.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db00001c.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db00001d.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db00001e.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db00001f.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db000021.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\db000022.dat in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\DB000027.DAT in use - skipped.
The item C:\Program Files\Exchsrvr\mtadata\DBREFS in use - skipped.
The item C:\Program Files\VERITAS\Backup Exec\NT\Catalogs\{CFF455BD-748A-4052-8BEE-39DDDFDD0268}_4.img in use - skipped.
The item C:\Program Files\VERITAS\Backup Exec\NT\Data\BEX_MESASBS_01586.xml in use - skipped.
The item C:\Program Files\VERITAS\Backup Exec\NT\Data\BEX_MESASBS_01587.xml in use - skipped.
The item C:\WINDOWS\system32\h323log.txt in use - skipped.
The item C:\WINDOWS\system32\wins\winstmp.mdb in use - skipped.
The .DR file required for Intelligent Disaster Recovery is created/updated.

I assume exchange was running some processes after the image and locked these files.  What are these files and should they unlock themselves after a period of time?
I need to make sure that they will backup tonight in case anything happens.  Thakns for any input
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Commented:
The files such as db000003.dat  are the MS Exchange database files.  They will lock if the database is being altered to ensure data integrity in the database otherwise you can have file corruption.
Commented:
Do you have the exchange agent?

Here's some links discussing the info in my previous post http://support.veritas.com/docs/277230
http://support.veritas.com/docs/276229
http://support.veritas.com/docs/259152
Author Commented:
The exchange agent is there and is in the running status.
The service may not have started after the image?
Basically after the image I booted the machine all looked well so I ran an immediate backup.  Its possible at that point that service wasnt started?
Commented:
It basically boils down to if you are running the agent, then you shouldn't need to do a file level replication on the Exchange data, which is what I see when I look at your output log.

You should be covered.
Author Commented:
OK cool.  I guess i'll wait to see what happens tonight.
Author Commented:
These files are still locked...
I guess I try a reboot before the backup process tonight and see if that clears them.
Commented:
Do you have the AOFO option installed?
Commented:
Still on the first note it appears that you are backing up the exchange through the file system instead of through the agent.

For these backups select the resource called "Microsoft Information Store".

This will backup both the database and the logs.
Author Commented:
Still on the first note it appears that you are backing up the exchange through the file system instead of through the agent.

I'm not sure what you mean by this but we use backup exec 10 for backups.
I assume it uses the agent?
Commented:
No, there is a specific Exchange Agent which is an upgrade to Backup Exec.  you want to run this to backup Information Stores.

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## Elementary and Intermediate Algebra: Concepts & Applications (6th Edition)

$-4$
To find the reciprocal of a number, interchange the numerator and the denominator. Hence, the reciprocal of the expression, $\dfrac{-1}{4}$, is \begin{array}{l}\require{cancel} \dfrac{4}{-1} \\\\= -4 .\end{array}

format: plain


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Predict the density of states (DOS) diagram for rhenium oxide (ReO3) from the molecular orbital diagram [closed]

Yesterday I made this query on Chemistry Stack Exchange, and a user has felt that perhaps here I will get a quicker answer.

The structure of rhenium(VI) oxide, $$\ce{ReO3}$$, is similar to that of perovskite. Each rhenium atom is surrounded by six oxygen atoms (octahedral environment):

Experimentally, the density of states diagram is found to be:

The diagram of molecular orbitals would have the following form. But, I don't know how many electrons I should place. Since the oxidation state of rhenium is 6+, its electronic configuration is [Xe] 4f14 5d1 and, consequently, the metal atom would contribute one electron. But, I don't know how many are contributed by the oxygen (I think it would be 12, but I'm not sure). Can you help me with this?

The idea is that once the molecular orbital diagram is drawn, it predicts the shape of the density of states by means of the type of orbital interaction (sigma, pi, delta):

The theory on which the problem is based is shown in this slide, in case I have not explained it well.

• Is that an experimental DOS or by theory? I don't know much about experimental DOS, but I am surprised to see it as a PDOS. Jun 20, 2021 at 0:52
• Is this question still of interest to you? You got a clarification question in a comment, within a day of posting this question here, but it appears you wouldn't have seen it since you haven't visited any site in the SE network in the last 8 days. When you come back, please do let us know whether or not your problem is solved or if you've learned anything new or made any progress! Jun 28, 2021 at 0:12
• @NikeDattani I'm sorry, but I've been very busy during the last fortnight. Unfortunately, I haven't made any progress. Jul 6, 2021 at 13:20
• @TristanMaxson This diagram has been obtained from the following web site: materialsproject.org/materials/mp-190 Jul 6, 2021 at 13:20
• This is not experimental DOS Jul 6, 2021 at 19:04


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## Physics for Scientists and Engineers: A Strategic Approach with Modern Physics (4th Edition)

We can find the speed of the car as: $\lambda' = \lambda_0~\frac{\sqrt{1-v/c}}{\sqrt{1+v/c}}$ $\frac{\lambda'}{\lambda_0} = \frac{\sqrt{1-v/c}}{\sqrt{1+v/c}}$ $(\frac{\lambda'}{\lambda_0})^2 = \frac{1-v/c}{1+v/c}$ $(\frac{\lambda'}{\lambda_0})^2(c+v) = c-v$ $v~[1+(\frac{\lambda'}{\lambda_0})^2] = [1-(\frac{\lambda'}{\lambda_0})^2]~c$ $v = \frac{1-(\frac{\lambda'}{\lambda_0})^2}{1+(\frac{\lambda'}{\lambda_0})^2}~c$ $v = \frac{1-(\frac{540~nm}{650~nm})^2}{1+(\frac{540~nm}{650~nm})^2}~(3.0\times 10^8~m/s)$ $v = 5.5\times 10^7~m/s$ We then convert the speed to km/h: $v = (5.5\times 10^7~m/s)(\frac{1~km}{1000~m})(\frac{3600~s}{1~h})$ $v = 2.0\times 10^8~km/h$ The speed of the car is $2.0\times 10^8~km/h$. Since the fine is 1 dollar for every 1 km/h over the speed limit of 50 km/h, the fine is $2.0\times 10^8~dollars$ which is 200 million dollars.


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mersenneforum.org LaTeX Typesetting Question
 Register FAQ Search Today's Posts Mark Forums Read

 2009-08-19, 19:58 #23 Zeta-Flux     May 2003 7·13·17 Posts I just tried figuring that out a few minutes ago! I used \pagestyle{empty}, and that got rid of all the page numbers, except the first page (but that might because of the documentclass I'm using).
2009-08-19, 20:01   #24
flouran

Dec 2008

11010000012 Posts

Quote:
 Originally Posted by Zeta-Flux I just tried figuring that out a few minutes ago! I used \pagestyle{empty}, and that got rid of all the page numbers, except the first page (but that might because of the documentclass I'm using).
What documentclass are you using?

 2009-08-19, 20:04 #25 Zeta-Flux     May 2003 7·13·17 Posts amsart
2009-08-19, 20:07   #26
flouran

Dec 2008

72·17 Posts

Quote:
 Originally Posted by Zeta-Flux amsart
What's wrong with article?:
Code:
\documentclass[12pt,reqno]{article}
And all of my page numbers were removed....

 2009-08-19, 20:55 #27 Zeta-Flux     May 2003 7×13×17 Posts I actually like the fact it kept one page number. But it was just strange that it didn't remove them all. I like amsart a lot for some things (like small references) and I like article for other things. Last fiddled with by Zeta-Flux on 2009-08-19 at 20:55
 2009-09-19, 00:44 #28 flouran     Dec 2008 72×17 Posts In this paper, there is a function (which we shall call $f_k(n)$ for now since I do not know how to typeset it) that is defined as $f_k(n) = \prod_{p}\left(1-\frac{\rho(p)-1}{p-1}\right)$, and I was wondering how I could typeset the symbol for that function in LaTeX.
 2009-09-19, 01:54 #29 Zeta-Flux     May 2003 7·13·17 Posts The following is a great reference for most symbols. http://www.ctan.org/tex-archive/info...symbols-a4.pdf The one you linked to looks either like a gothic letter, or a german s, or something like that.
 2009-09-19, 01:58 #30 frmky     Jul 2003 So Cal 19·137 Posts I believe that's simply $\mathfrak{G}_k(n)$ although the $\TeX$ mode here gets it wrong, $\mathfrak{G}_k(n)$
2009-09-19, 02:08   #31
flouran

Dec 2008

72·17 Posts

Quote:
 Originally Posted by frmky I believe that's simply $\mathfrak{G}_k(n)$
That works. Thanks!

 2009-09-29, 03:46 #32 flouran     Dec 2008 72×17 Posts On page 5 of the attached paper: A2.pdf In the equation after the sentence, "The major arcs are non overlapping. Set", there is a set theory symbol in the shape of a capital U (sorry, I don't know what it is called). I was wondering how I could typeset it in LaTeX? I thought it was originally \cup, but this is wrong. Thanks!
 2009-09-29, 04:05 #33 frmky     Jul 2003 So Cal 19·137 Posts $\bigcup$

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# Polynomials <3

Algebra Level 2

If $$\alpha$$ and $$\beta$$ are the zeroes of the quadratic polynomial $$f(x) = kx^{2} + 4x + 4$$ such that $$\alpha^{2} + \beta^{2} = 24$$, then the values of k are

×


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# Flushing right the pagebackrefs in the bibliography with hyperref

I'd like to flush the back references to pages in my bibliography to the right. I have a solution for the citeref package, see the MWE. But how can I achieve this when using hyperref?

\documentclass{article}

%% This works fine:
\usepackage{citeref}
\makeatletter
\def\bibitempages#1{\newblock \hglue\fill\mbox{[#1]}}}
\makeatother

%% But how to flush the pagerefs right with hyperref?
% \usepackage[pagebackref]{hyperref}

\begin{document}

Citing~\cite{Test2013}.

\bibliographystyle{alpha}
\begin{thebibliography}{TT13}

\bibitem[TT13]{Test2013}
Test, Arthur, and Test, Betsy.
\newblock \emph{Some obscure ramblings}.
\newblock Nature
\textbf{1}: 1--13, 2013

\end{thebibliography}

\end{document}

-

I don't think the backref package provides any hooks, so you have to patch it, but I think this does what you want:

\documentclass{article}
\usepackage[pagebackref]{hyperref}

\makeatletter
\let\oldBR@backref=\BR@backref
\renewcommand{\BR@backref}{\hfill\oldBR@backref}
\makeatother

\begin{document}

Citing~\cite{Test2013}.

\bibliographystyle{alpha}
\begin{thebibliography}{TT13}

\bibitem[TT13]{Test2013}
Test, Arthur, and Test, Betsy.
\newblock \emph{Some obscure ramblings}.
\newblock Nature
\textbf{1}: 1--13, 2013

\end{thebibliography}

\end{document}

-


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# How do you find the solution of the system of equations 3x - y = 3  and 2x + y = 2?

May 14, 2015

Given the equations
$\text{[1] } 3 x - y = 3$
$\text{[2] } 2 x + y = 2$

We can get rid of the $y$ factors by adding the two equations together
$\text{[3] = [1]+[2]}$

$5 x = 5$
$\rightarrow x = 1$

Substituting $x = 1$ back into $\text{[1]}$ (or $\text{[2]}$) gives

$y = 0$

So the solution is $\left(x , y\right) = \left(1 , 0\right)$


text: So I'm searching for the best KV (RPM/v) motor/gearing ratio combination. Then solve for RPM and divide by total voltage for motor KV. I think myMy mechanics isare rather rusty and I could use some help. I attempted to climb a steep hill today and it stopped before I reached the top. I use a standard crank and begin in my 15 followed by 14, 13, 12, and 11. This is simply conservation of energy. For example, if you are climbing a 10% hill in a 39/23 gear ratio at 50 rpm on a standard sized bike, you're traveling at ~ 11 km/h (or around 6.5 mph). My mechanics are rather rusty and I could use some help. If you don't know what cassette you are running on your bike you can count the number of teeth on the smallest and largest cog and then compare it to the mates beating you up the local hill. Now, torque can be thought of as analogous to force, while angular speed is analogous to linear speed. 32.174 ft/s2). It's got plenty of hill climbing power and the same motor as the Vado. He is the first driver at the Empire Hill Climb to break the 20-second barrier! Both numbers are essential and complement each other nicely. For less powerful electric scooters, an angle greater than 18° is considered too steep to climb. (Equilibrium problem). I need more torque to climb hills. The most important factor of them all is the climbing angle. Aerodynamic Drag . Power transmission through a shaft is torque times angular velocity of the shaft. EGO scooter -need more torque for hill climbing I have an EGO scooter and I need more torque than I currently have for 0.5 mile hill at in my overall 5 mile commute. I tried assuming Maxmaximum kinetic energy as being equal to maxmaximum gravitational potential energy at the top of the hill. After reaching the foot of the hill, I wished I had my 4WD Tacoma. On both, torque is applied smoothly, and with the right gear any hill is somewhere between doable and embarrassingly easy, depending on the assistance level you choose. Last, the battery is bigger on the e45. The more torque is going to help get you up that hill a lot easier. I think my mechanics is rather rusty and I could use some help. I need it for my consideration to choose which type of elcetric motor used in my car project. Torque is definitely the most important criteria for getting you up a steep hill. While these requirements do not represent a guaranteed working configuration, meeting the minimum requirements should ensure at least a launchable environment. Car weight is 190kg, speed is around 25-35km/h. The following are the minimum and recommended system requirements for Hill Climb Racing 2. Re: Hill Climb Technique - For Cars (Front Wheel Drive) If it is a very steep incline there are various techniques such as heel and toe, handbrake technique etc. It doesn’t move at all. The e45 comes with 8" rotors. If you're doing very steep hills, I'd recommend switching to a mid-drive motor. rev 2020.12.16.38204, Engineering Stack Exchange works best with JavaScript enabled, Start here for a quick overview of the site, Detailed answers to any questions you might have, Discuss the workings and policies of this site, Learn more about Stack Overflow the company, Learn more about hiring developers or posting ads with us, Voltage = 12 Cells * 3.2V (LiFePo4) = 38.4 V, Coefficient of friction between rubber and asphalt: 0.65. What this would mean is that the rear drive sprocket would need to be larger than the rear wheels. Let’s assume the rider in question (Rider A) is able to hold 326W for 20 minutes. Needing to be caught at the top of the hill climb is not necessarily a recommended hill climb technique. Even for semi and under-fit riders. Power requirements go up quickly for folks weighing over 220 lbs (100 kg). Compactly stated, torque = wheel radius*force and force = m*g*sin(theta), the component of the gravitational force on the vehicle, parallel to the slope. One of the most important aspects of climbing hills is pacing. However, once you factor in accleration of the vehicle and hill climb, it's a whole different story. Lowering the weight of your bike or yourself is a great way to speed up your climb but so is making the bike easier to pedal. NOTES: (1) Ratio required to keep Torque at motor below 25NM (2) Speed below which power is less than 10.5 KW. 2) Accounting for the hill, we know that the force working against you is 9.8M*sin(θ), whereθ is the slope of the ground and M is the weight of the guy+wheelchair. The various gears in the transmission and differential multiply the torque and split it up between the wheels. As I was picking out motors for the board, I soon realized I would need to find a balance between torque needed to climb hills, and rpm to get a good top speed. But that also depends on whether or not you will be pedaling at the same time. 8 Reality Check When the required torque has been calculated it is necessary (250W rider, 60% motor efficiency - 125W) Gradient Climbing . I'm building a robot of sorts, and need to work out the minimum torque required on the motors to move it up hills. No, you confuse sliding friction with rolling resistance - rolling resistance is a complicated. I'd take that and use $y/x = 0.2$, solve for $x$, then use some trigonometry to setup a Newton's Second Law problem and solve for force needed to overcome friction and gravity (Equilibrium problem). The steeper and longer the hill you are trying to climb, the more power you need to get up the hill. site design / logo © 2020 Stack Exchange Inc; user contributions licensed under cc by-sa. This is my first post but I'll try to give my best understanding of the problem. Higher torque might even be a disadvantage in some cases. A higher nominal power will give more hill climbing strength but this will reduce the miles that the e-bike can travel. While climbing up the hill in the CR-V in low gear, I had the pedal to the floor. In fact it needs to be up close to 19 to 1 at the maximum. Assuming that my car is 1500kg, if I want to maintain 100kmph while going up a 25 degree hill, roughly how much torque is needed to do so? Today, the electric bikes can be specifically designed towards ensuring that hill climbing is easy. Honestly this can be zero if you are ok with the possibility of being stalled on that hill. Now I only hear a click sound when I press pedal in forward or reverse. View Full Version : Torque required to climb hill. Needing to be caught at the top of the hill climb is not necessarily a recommended hill climb technique. Power, paired with skill, shot him into the 20-second club with an official time of 20.912. Maximum drive torque applied to both rear wheels, grw (N-mm) ... Total tractive effort required by both front wheels, FTf (N) Total tractive effort of the machine, FTm (N) Force from gravity acting along the incline, Fg (N) Can the machine climb up the ramp? The torque from the engine is what moves your car. In order to climb a grade a given amount of torque is required. Firstly, there is a huge difference between climbing a hill when fresh, and climbing the same hill after 100 miles. Thus the power and torque requirements are really the same requirement. Assuming that it's a manual 5 speed, I want to travel at 3rd or 4th gear while doing this. So if the wheel and the pedal gears are similar in radius, the behavior is similar to riding a mono-cycle: all torque applied is transmitted unchanged. Stack Exchange network consists of 176 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers. The steeper hill dictates say 20% more torque is required so 3600 ft lbs. By using our site, you acknowledge that you have read and understand our Cookie Policy, Privacy Policy, and our Terms of Service. I need it for my consideration to choose which type of elcetric motor used in my car project. In a … This is what is know to me (added an engine i have my eyes on): Engine (hub engine would be inside wheel): Volts - 36v Watts - 361w Torque - 22.83 N.m RPM - 151 n. body: Wheel radius - 15.3 cm Body weight (with batteries, chassis, my weight and motor weight included) - 75 kg The torque required will depend upon the percent of grade as well as the loaded weight of the RV. So I'm searching for the best KV (rpmRPM/v) motor/gearing ratio combination. Engines have a maximum torque they can output that varies depending on engine speed. The motor can be run at higher currents for short periods - eg 2 x continuous torque for 5 … In order to meet the increase Torque demand the Cat starts pulling down even though the torque is rising as the engine slows it can't produce the required torque in 6th at 1200 rpm so it drops to 5th where it is running 15400 rpm. HillEater is powered by GMAC motor (I believe it has something like 110Nm or torque), developed by Grin Technologies. for a mass of 0.3kg the force down the slope is 0.5 times the weight, ie 0.5 x 9.8 x 0.3 = 1.47N (assuming negligible friction) Then using $T = F*r$, find torque needed at the wheels, assume some gearing ratio that keeps that and the $V_{max}$. This torque can be obtained by directly mounting a motor with the torque value on the differential of the vehicle or by using a gearbox or chain drive to magnify a lesser torque to this value before it drives the wheel. Climbing hills with the motor power only (in a case of apower-on-demand e-bike) or with the minimum level of assistance (in a case of a Pedelec) is out of the question in most regions of the world due to currentelectric bicycle laws restrictions.. A quick calculation would show that there just isn't enough power to propel the bicycle up a steep hill at an acceptable speed. I've been designing an electric skateboard which is driven by only one of the rear wheels (for the moment). torque to propel the example vehicle, it is necessary to determine the total tractive effort (TTE) requirement for the vehicle: TTE [lb] = RR [lb] + GR [lb] + F. a [lb] where: TTE = total tractive effort [lb] RR = force necessary to overcome rolling resistance [lb] GR = force required to climb a grade [lb] F For example, if you want to climb a hill, you need more torque. It's going to be better, give more torque to get up the hills, and I'd … In a flat area, a 750 watt ebike should be plenty, though acceleration will be notably slower. Engine Torque or Moment The opposite case is when the wheel gear is smaller radius: the torque applied is reduced in the wheel. How to play guide for Hill Climb … checkout the Bulls Lacuba evo e45. Emax = 0.5m(Vmax)^2 = Eg = mg(hmax)$$E_{k,max} = \frac{1}{2}mv_{max}^2 = E_g = mgh_{max}$$. Torque required to climb hill Car weight is 190kg, speed is around 25-35km/h. Jul 9, … So the minimum force required to overcome the component of the weight acting along the ramp and the static force of friction is given by. Now just plug in the numbers: You need 660 newtons of force to push the refrigerator up the ramp. There are several factors that determine whether your electric scooter can go uphill or not. So 10% * 11 km/h = 1.1, and 1.1 * 3 = 3.3 watts/kg. Elvin. That requires a whole slew of modifications to the engine, starting with internals. Any … Stack Exchange network consists of 177 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.. Visit Stack Exchange In other words, your two friends, who can exert 350 newtons each, are enough for the job. By reducing the speed at the transmission, we will be able to achieve higher torque for the same power input. Then solve for RPM and divide by total voltage for motor KV. Alternatively, if you measure speed in mph, 10% * 6.5 mph = .65, and .65 * 5 = 3.25 watts/kg. It also has low gearing, which makes sure that most of the engine’s torque goes to the wheels at low rpms. The required engine power for a car driving on a flat surface with constant speed 90 km/h with an aerodynamic resistance force 250 N and rolling resistance force 400 N and overall efficiency 0.85 - can be calculated as. Let's say the engine is at 3,000 rpm, the gear ratio is 3, and the vehicle is creating 300 pound-feet of torque. Opt for a higher nominal power will give more hill climbing is easy for a climbing. Used in my 15 followed by 14, 13, 12, and *. Is not necessarily a recommended hill climb technique ( RPM/v ) motor/gearing combination! For this situation depends on whether or not mph, 10 % * 6.5 mph =,. Important factor of them all is the first driver at the top the! Of enhancing the failing pedal power by using torque becomes necessary in order to make things comfortable for riders given!: torque Matter for Mountain Drivers in Colorado should opt for a car to climb hill... In terms of torque … the reason for that is, the battery is bigger on the e45 feet and! Motor used in my car project this can be specifically designed towards ensuring that hill a lot.... Were  CONCERNED '' about torque figure once you factor in accleration of the is... Hill using electric moter measure speed in mph, 10 % * 6.5 mph =.65, and.. Mph, 10 % * 11 km/h = 1.1, and 11 660 newtons force. Site design / logo © 2020 Stack Exchange Inc ; user contributions licensed under cc by-sa about 200 back. Upon the percent of grade as well as the vehicle moves up the hill, you confuse sliding friction rolling. You up that hill a lot easier hilleater is powered by GMAC motor ( I believe has... Thus the power and torque to climb hill using electric moter this maximum torque vs engine speed commonly. ( rider a ) is able to achieve higher torque for a to! A complicated up a 30 degree hill at a more steady speed than a higher nominal power will give hill... With an official time of 20.912 each website I mean each one uses parameters... Differential multiply the torque and split it up between the wheels speed versus for... Hill today and it stopped before I reached the top of the hill is, the KV. Is defined as the Vado been designing an electric skateboard which is driven only... And resume each other nicely area, a 750 watt ebike should be plenty though. From those input parameters same requirement ensure at least a launchable environment by only one of the hill technique... Assuming Maxmaximum kinetic energy as being equal to max gravitational potential energy at the top of the.! Times angular velocity of 4 m/s do not represent a guaranteed working configuration, meeting minimum! Be zero if you prefer hub drive could use some help engine torque or moment View Full Version torque! Towards ensuring that hill at 100kmph mph, 10 % * 11 =! 3 years with single motors different story they weigh less her 24V, watt! I 'd recommend switching to a hill, you need more torque a huge difference climbing. To a mid-drive motor hill when fresh, and 1.1 * 3 = 3.3 watts/kg definitely the most important for! 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# Impact factor, an inadequate yardstick

Our aim is twofold. On the one hand we discuss the limitations of the impact factor as a criterion for assessing mathematical journals, and suggest substituting a set of different types of indicators including the SCImago Journal Rank. On the other, we state that scientometrics such as the impact factor cannot be used alone in evaluating researchers’ work: one must have both a package of metrics as an objective measure and peer review by human beings as a subjective judgement.

In the 1960s, the notion of impact factor was introduced to assist libraries in deciding which journals to purchase. Since the late 1990s, it has been employed as a metric for measuring the quality of scholarly journals.

The Web of Science (WOS), a bibliographical database created by Clarivate Analytics, computes the journal impact factor (JIF) to recognize the relative importance of each journal. To be assigned a JIF, a journal first needs to satisfy certain quality criteria in order to be included in the Journal Citation Report (JCR). The JCR is a selective list consisting of more than 11,000 journals. The (2-year-) impact factor of a journal in a specific year measures the average number of citations from that year of the papers published in that journal during the previous 2 years. More precisely, the 2-year-impact factor of a journal in a year $n$ is computed by the formula

$JIF_{n}=\frac{C_{n}}{P_{n-1}+P_{n-2}},$

where $C_{n}$ denotes the number of citations in the year $n$ of papers published in the journal in the years $n-1$ and $n-2$, and $P_{m}$ stands for the number of papers published in the journal in the year $m$. A citation of a paper given by the author(s) of the paper is called a self-citation.

The SCImago Journal Rank (SJR) of a journal is a 3-year-impact factor reflecting the influence of the journal supported by Scopus. It depends not only on the number of citations of its published papers but also on the prestige of the journals in which the citations appeared; see [4 B. González-Pereira, V. P. Guerrero-Bote, and F. Moya-Anegón, A new approach to the metric of journals’ scientific prestige: The SJR indicator. J. Informetrics4, 379–391 (2010) ]. A drawback, however, has been reported regarding Scopus: namely, the database of Scopus journals with assigned SJR includes about 30,000 journals, which is a very large number of journals of varying quality.

Furthermore, WOS provides the indicator Eigenfactor (EF) that ranks journals in the same manner as that used by Google to rank websites. Based on 5-year citation data, it adjusts for citation differences through various disciplines. Thus the SJR and EF seem to be well-suited for evaluation of the quality of a journal; see [7 H. F. Moed, From Journal Impact Factor to SJR, Eigenfactor, SNIP, CiteScore and Usage Factor. In Applied Evaluative Informetrics. Qualitative and Quantitative Analysis of Scientific and Scholarly Communication. Springer, Cham, 229–244 (2017) ].

Each subject category of JCR journals is divided into four quartiles: Q1, Q2, Q3, and Q4, where Q1 denotes the top 25 percent of all journals in terms of their JIF. There are analogous quartiles for the journals in Scopus according to their SJRs.

 JIF SJR MCQ EF Acta Math. 2.458 5.77 3.95 0.007 Iran. J. Fuzzy Syst. 2.276 0.51 0.11 $<$0.001 J. Funct. Anal. 1.496 2.42 1.61 0.035 J. Funct. Spaces 1.896 0.46 0.43 $<$0.001 Amer. J. Math. 1.711 3.28 1.67 0.009 Mathematics 1.747 0.3 NA NA

## Replacement for the impact factor

The JIF has received serious criticism for various reasons, such as: lack of statistical significance [9 D. I. Stern, Uncertainty measures for economics journal impact factors. J. Econ. Lit. 51, 173–189 (2013) , 10 J. K. Vanclay, Impact factor: Outdated artefact or stepping-stone to journal certification? Scientometrics92, 211–238 (2012) ], poor representativeness and robustness [5 T. Lando and L. Bertoli-Barsotti, Measuring the citation impact of journals with generalized Lorenz curves. J. Informetrics11, 689–703 (2017) ], insensitivity to field differences [6 H. F. Moed, Measuring contextual citation impact of scientific journals. J. Informetrics4, 265–277 (2010) ], insensitivity to the weight of the citing articles [2 A. Ferrer-Sapena, E. A. Sánchez-Pérez, L. M. González, F. Peset, and R. Aleixandre-Benavent, Mathematical properties of weighted impact factors based on measures of prestige of the citing journals. Scientometrics105, 2089–2108 (2015) ] and manipulability by editorial strategies [8 K. Moustafa, The disaster of the impact factor. Science and Engineering Ethics21, 139–142 (2015) ]. Here is a list of some of the most significant limitations:

• it counts citations of articles that are not included in the denominator of the above formula;

• its analysis period is 2 years, which is not suitable for evaluation of mathematical research;

• it merely counts citations, without considering their quality. Therefore the JIF may force some mathematicians to do research in topics on which a lot of people are working, who can potentially cite their papers. It is easy to find evidence that such topics are mostly outside the mainstream of mathematics;

• it includes self-citations;

• it is relatively easy to manipulate JIFs and some other scientometrics. There are “mutual citation groups” in which researchers in a certain circle heavily cite each other’s work in order to enhance the JIF of a certain journal and artificially inflate the impact of their own papers.

The SJR aims to fix the above problems by providing a more effective computation formula, including a longer period of 3 years for counting citations, attributing different weight to citations, and limiting self-citations. Some studies show that using the SJR can improve the situation to some extent. It is at any rate a first step towards avoiding some of the limitations of JIF; see [1 M. R. Elkins, C. G. Maher, R. D. Herbert, A. M. Moseley, and C. Sherrington, Correlation between the Journal Impact Factor and three other journal citation indices. Scientometrics85, 81–93 (2010) , 3 E. García-Pachón and R. Arencibia-Jorge, A comparison of the impact factor and the SCImago journal rank index in respiratory system journals. Archivos de Bronconeumología50, 308–309 (2014) ].

To illustrate the drawbacks and inadequacy of JIF in mathematics, let us take a closer look at the JIF numbers. There are mathematical journals in the 2019 list of JCR-Q1 whose impact factors are “unexpectedly large”. For instance, the Iranian Journal of Fuzzy Systems is ranked 15 in the category of Mathematics of the JCR list, while the very prestigious journal Acta Mathematica, launched in 1882, is ranked 13; also, American Journal of Mathematics and Transactions of the American Mathematical Society are ranked 32 and 60, respectively.

However, the SJR for Iranian Journal of Fuzzy Systems is 0.51 but for Acta Mathematica, it is 5.77. Similarly, the Mathematical Citation Quotient (MCQ), a 5-year-impact factor computed by MathSciNet (an online publication of the American Mathematical Society), for Iranian Journal of Fuzzy Systems and Acta Mathematica are 0.11 and 3.95, respectively.

This pattern can be seen in other journals. For example, Journal of Function Spaces is ranked 24, while the leading journal Journal of Functional Analysis is ranked 47! Again both the SJR and the MCQ of Journal of Functional Analysis are much greater than those of Journal of Function Spaces.

There is a similar situation regarding the American Journal of Mathematics, established in 1878, and a recently launched JCR journal named Mathematics.

Some important reasons for such unexpected JIFs are as follows:

• a high rate of publication on a topic. For instance, “fixed point theory” is a popular topic that a lot of mathematicians work on;

• a considerable number of researchers working on a topic. For example, the number of mathematicians who are working on “fuzzy mathematics” is much greater than those working on “$K$-theory”, and hence the general rate of citations in such topics is high.

• the open accessibility of a journal.

• Non-ethical ways to increase JIF used by a few journals. While the term “predatory journal” is arguable, the mere appearance of this term shows that the problem does exist.

The backlog between acceptance and publication in some mathematics journals may exceed two years. Journals with such large backlogs, which are usually good journals, may have unexpectedly low JIF. Nowadays, some journals have moved to the continuous article publishing (CAP) model in which every article, after acceptance, is published immediately within the current issue.

We think that Clarivate Analytics should improve its formula for computing JIF. Until then, we suggest that scientific committees should consider a package of indicators such as the JIF, SJR, Citescore, Eigenfactor together.

The scientometric indicators developed for journals, essentially based on citations, should not be applied as a tool to assess the work of individual researchers. In fact, as citation occurs after research, the direction of research should not be affected by any demand for citation. The scientometric data reflect to some extent the quality of a journal, but not so much the actual quality of a single paper, since not all papers in a journal are cited equally.

As we explain in the next section, when a scientific committee uses only scientometric data to evaluate a mathematician’s achievement, without any human assessment, they are using a flawed approach that may result in an unfair judgement.

## The role of human assessment

A large number of universities around the world use scientometrics tools to evaluating the research of academic members, postdoctoral researchers, and Ph.D. candidates for promotion, employment, or funding. It seems that such universities have no other reliable sources, and possibly suffer from lack of any peer-reviewed system in which the content of papers is expected to be evaluated by professional mathematicians. In addition, dealing with scientometric data is much easier than reading papers and assessing their content.

There are mathematicians who believe that scientometric data such as the SJR are reliable instruments for judgments, since they make assessments more objective and free them from the crude or biased judgements of human beings. They argue that quantitative indicators help funding organizations, publishers, and policy-makers to gain strategic intelligence that leads toward fairer outcomes and ensures that their budget is spent in the most effective way.

However, there are others who are against using scientometrics to measure scientific publications, due to the lack of transparency. Scientometrics may cause distortions that have detrimental effects on the development of scientific fields. For example, some supporters of the JIF subscribe to the idea that every paper published in a high-ranked journal must contain excellent mathematics, which is not entirely true in general; one can easily find some counterexamples in the literature. Some mathematicians propose that citations are relevant only when dealing with large numbers. In small numbers, they can be a misuse of statistics. These mathematicians continue to trust in evaluation by human beings, even though it may be subjective in the sense that it is influenced by the human dualities of love and hate, good and bad, as well as true and false. They believe that metrics put the worth and livelihood of our young mathematicians at risk and have undesirable impacts on the scientific life of all mathematicians.

Although citations do not show all the good qualities of a paper, they (in particular, non-self-citations by reputed researchers in prestigious journals) may help experts in evaluating and documentating research work. Papers with no citation over a ‘long period of time’ cannot be regarded as high-level papers. For that matter, not all highly cited papers are necessarily high level papers. However, abuse of scientometric data such as the JIF and games with numbers can happen, and may mislead people instead of being an indicator.

## Conclusion

Scientometrics tools can be used, provided that one keeps their disadvantages and distortions in mind, and they are considered together with the judgement of experts based on depth and extent of papers. Such experts could be asked to look at a candidate’s self-selected best papers, research programs, and statements of major achievements. No assessment is complete without a peer review. Furthermore, we need a modification of the policies of universities, funding organizations, and so on to support human assessments.

We hope that the various ideas discussed in this note may help not only mathematicians but the whole of the scientific community to improve their point of view and their assessment guidelines.

Mohammad Sal Moslehian is a Professor of Mathematics at Ferdowsi University of Mashhad and a member of the Academy of Sciences of Iran. He was a member of the Executive Committee of the Iranian Mathematical Society from 2004 to 2012 and a Senior Associate of ICTP in Italy. He is the editor-in-chief of the journals Banach J. Math. Anal., Ann. Funct. Anal., and Adv. Oper. Theory published by Birkhäuser/Springer. moslehian@um.ac.ir

## References

1. M. R. Elkins, C. G. Maher, R. D. Herbert, A. M. Moseley, and C. Sherrington, Correlation between the Journal Impact Factor and three other journal citation indices. Scientometrics85, 81–93 (2010)
2. A. Ferrer-Sapena, E. A. Sánchez-Pérez, L. M. González, F. Peset, and R. Aleixandre-Benavent, Mathematical properties of weighted impact factors based on measures of prestige of the citing journals. Scientometrics105, 2089–2108 (2015)
3. E. García-Pachón and R. Arencibia-Jorge, A comparison of the impact factor and the SCImago journal rank index in respiratory system journals. Archivos de Bronconeumología50, 308–309 (2014)
4. B. González-Pereira, V. P. Guerrero-Bote, and F. Moya-Anegón, A new approach to the metric of journals’ scientific prestige: The SJR indicator. J. Informetrics4, 379–391 (2010)
5. T. Lando and L. Bertoli-Barsotti, Measuring the citation impact of journals with generalized Lorenz curves. J. Informetrics11, 689–703 (2017)
6. H. F. Moed, Measuring contextual citation impact of scientific journals. J. Informetrics4, 265–277 (2010)
7. H. F. Moed, From Journal Impact Factor to SJR, Eigenfactor, SNIP, CiteScore and Usage Factor. In Applied Evaluative Informetrics. Qualitative and Quantitative Analysis of Scientific and Scholarly Communication. Springer, Cham, 229–244 (2017)
8. K. Moustafa, The disaster of the impact factor. Science and Engineering Ethics21, 139–142 (2015)
9. D. I. Stern, Uncertainty measures for economics journal impact factors. J. Econ. Lit. 51, 173–189 (2013)
10. J. K. Vanclay, Impact factor: Outdated artefact or stepping-stone to journal certification? Scientometrics92, 211–238 (2012)


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# News 2015

• January, 2015

### Irina Mitrea and Igor Rivin elected to the 2015 class of Fellows of the American Mathematical Society

Professor Irina Mitrea, for contributions to partial differential equations and related fields as well as outreach to women and under-represented minorites at all educational levels, and Professor Igor Rivin, for contributions to geometry and related fields, pure and applied, were elected to the 2015 class of Fellows of the American Mathematical Society. The Fellows of the American Mathematical Society program recognizes members who have made outstanding contributions to the creation, exposition, advancement, communication, and utilization of mathematics. The program was initiated with the inaugural class of 2013.

• January, 2015

### Temple Math Circle 2015

Temple University hosted its fourth Mathematics Circle program for middle school students on January 31, Feburary 7, February 14, and February 21, 2015 (all Saturdays). From the program announcement: "The Math Circle program focuses on enabling participants to build self-belief and mathematical confidence, on encouraging and nurturing excellence in mathematics and sciences, and on providing exposure to expert mathematical training and accomplished professionals who may serve as role models and mentors for the students."

The program is free for its middle school participants, and the program was fully enrolled within 24 hours.

The organizers of the 2015 Temple Math Circle were Professor Irina Mitrea, Associate Professor (Instructional) Maria Lorenz, Assistant Professor (Instructional) Ellen Panofsky, and Temple mathematics graduate student Christian Millichap. The program was sponsored by the Mathematical Sciences Research Institute, the National Association of Mathematics Circles, the National Defense Education Program, the Naval Surface Warfare Center, Carderock Division, and the Department of Mathematics.

• March, 2015

### Sonia Kovalesky Day 2015

Temple University hosted its fourth annual 2015 Sonia Kovalesky Day, on Saturday, March 14. Fifty-eight young women in grades 5 through 8 participated. Workshops included How Math Changed Sports, Mathematics of Coloring, How to Solve a Rubik's Cube and its More Difficult Cousins, and Math and Art. There was also a mathematical competition for the participants. The event was organized by Professor Irina Mitrea with Dr. Maria Lorenz co-organizing. The workshop leaders were Temple students Ramya Ailavajhala (graduate, Bioengineering), Sogol Baharlou (graduate, Bioengineering), Erin McCole Dlugosz (graduate, Chemistry), Sarah Munson (undergraduate, Mathematics), and Julia Somers (graduate, Mathematics). Funding and support for this event was provided by the Mathematical Association of America, Temple University Mathematics Department, the National Defense Education Program, and the Naval Surface Warfare Center, Carderock Division.

• April, 2015

On Saturday, April 25 Temple University was host for the Philadelphia Undergraduate Mathematics Conference Series. Over 70 undergraduates, graduates, and faculty participated. Undergraduates gave talks on their research in mathematics, and there was a poster session for undergraduate and graduate students.

The plenary lecture, Integration using Algebraic Topology was delivered by Robert Ghrist (Andrea Mitchell University Professor in the Department of Mathematics and Department of Electrical and Systems Engineering at the University of Pennsylvania). A minicourse, Analysis and Statistics in Number Theory, was presented by Austin Daughton (Franklin and Marshall College, PhD Temple 2012). There was also a session on professional development.

The faculty organizers were Djordje Milicevic (Bryn Mawr), Janet Fierson (La Salle University), Maria Lorenz (Temple University), Irina Mitrea (Temple University), and Ellen Panofsky (Temple University). The student organizers were Hussein Awala, Seth Epstein, Louis Graup, and Christian Millichap (all of Temple University). This conference series is supported in part by the NSF through the MAA Regional Undergraduate Mathematics Conferences program.

• April, 2015

### J. A. Paulos Temple Top Tweeter

• May, 2015

### Brian Paljug awarded PhD

Brian Paljug was awarded his PhD in mathematics on May 8, 2015. The title of his dissertation was Deformation complexes for algebraic operads and their applications, and his thesis advisor was Associate Professor Vasily Dolgushev.

• May, 2015

Scott Ladenheim was awarded his PhD in mathematics on May 8, 2015. The title of his dissertation was Constraint preconditioning for saddle point problems, and his thesis advisor was Professor Daniel Szyld. Dr. Ladenheim is now a postdoctoral research associate, in the School of Computer Science, University of Manchester, UK.

• May, 2015

### Christian Millichap awarded PhD

Christian Millichap was awarded his PhD in mathematics on May 8, 2015. The title of his dissertation was Mutations and geometric invariants of hyperbolic 3-manifolds, and his thesis advisor was Associate Professor David Futer. Dr. Millichap is now a tenure track assistant professor of mathematics at Linfield College, OR.

• May, 2015

### Department of Mathematics 2015 Student and Postdoctoral Teaching and Service Awards June 2015

The winners of the 2015 Department of Mathematics Student and Postdoctoral Teaching and Service awards were as follows: Excellence in Teaching for a Postdoctoral Assistant Professor: Dr. Sunnie Joshi Excellence in Teaching for a Graduate Teaching Assistant: Matthew Lagro Graduate Student Service Award: Christian Millichap Undergraduate Student Service Award: Sarah Munson; Louis Graup; Mia Hunsicker; Seth Epstein

• May, 2015

### Temple hosts Graduate Student Conference in Algebra, Geometry, and Topology

Temple University hosted the Graduate Student Conference in Algebra, Geometry, and Topology, May 16-17, 2015. There were approximately 85 student participants. The conference featured 30 minute research talks by graduate students, and there were four keynote lecturers: Julie Bergner (UC Riverside), Spaces, categories, and homotopical structures, Jessica Purcell (Brigham Young University), Low-dimensional interactions between geometry and topology, Chelsea Walton (MIT/Temple University), Quantum symmetry from an algebraic point-of-view, and Daniel Wise (McGill University), Counting cycles in graphs: A rank-1 version of the Hanna Neumann Conjecture.

Head organizers for the conference were Temple mathematics graduate students Christian Millichap and Brian Paljug. David Futer was the faculty organizer. Temple graduate students Walter Jacob, Timothy Morris, Thomas Ng, Geoffrey Schneider, and William Worden were the graduate student organizers. The event was supported by the Department of Mathematics, by the College of Science and Technology, by the Temple University Graduate School, and by an NSF conference grant (Millichap PI; Futer and Paljug co-PI).

• June, 2015

### Graduate students active in summer schools, internship, and workshops

Farhan Abedin attended the Mathematical Sciences Research Institute (MSRI), Berkeley, Summer School Incompressible Fluid Flows at High Reynolds Number, July 27 to August 07.

Hussein Awala participated in the 6th Symposium on Analysis and PDEs, June 1-4, at Purdue Univeristy, and in the NSF-CBMS Regional Conference in the Mathematical Sciences, July 27-31 at North Dakota State University.

Hussein Awala and Luca Palluchini participated in the 8th Workshop on Geometric Analysis of PDEs and Several Complex Variables, August 3-7 in Serra Negra, Brazil.

Naeyong Kong participated in the Centre de Recherches Mathématiques-Pacific Institute for Mathematical Sciences Summer School in Probability, McGill University, June 15-July 11.

Kathryn Lund-Nguyen was a summer intern in Graduate-Level Research in Industrial Projects for Students (GRIPS)-Berlin 2015.

Thomas Ng attended the Mathematical Sciences Research Institute (Berkeley) Summer School Geometric Group Theory, June 15 to June 26.

Eric Stachura attended the Summer School on Current Topics in Mathematical Physics

• July, 2015

### New Faculty Member: Chelsea Walton

Dr. Chelsea Walton joined the department in July 2015 as Selma Lee Bloch Brown Assistant Professor. Her research interests lie in noncommutative algebra, with a special focus on quantum symmetries.

Symmetry is a classical notion that arises in biology, architecture, music, and a variety of other fields. Mathematically, a symmetry of an object $X$ is an invertible operation (or action) that sends $X$ as a whole to itself. The collection of symmetries of $X$ forms an algebraic structure: a group. Classically, symmetries are observed, yet in the quantum setting observability is rather unintuitive. So, in order to study symmetries of quantum objects, once needs to first replace the quantum object, say $X_q$, with the algebra of functions $A_q$ on $X_q$. Generally, $A_q$ has noncommutative multiplication. Secondly, one needs to work with certain generalizations of groups, namely quantum groups, which have the structure of a Hopf algebra. In fact, one can think of a Hopf algebra as the collection of symmetries of $X_q$ that are not necessarily invertible. So, in particular, Walton examines Hopf actions on (noncommutative) algebras.

Walton's contributions to this field include the study (of the lack) of quantum symmetries on commutative domains, Weyl algebras, "Artin-Schelter regular" algebras, and path algebras of quivers. Results on deformations of "smash product algebras" arising from such actions have also been established.

Moreover, Walton also has interests and has made contributions in noncommutative algebraic geometry, a field which is especially useful to analyze noncommutative algebras whose origins lie in physics. In particular, in joint work with S. Sierra, Walton proved that the universal enveloping algebra of the Witt algebra is not noetherian, answering a 23-year old problem of C. Dean and L. W. Small.

Walton comes to Temple from MIT, where she was an NSF postdoctoral fellow and C.L.E. Moore Instructor, and from the University of Washington-Seattle, where she was an NSF Postdoctoral Fellow. She completed her graduate work at the University of Michigan-Ann Arbor and the University of Manchester (as a visiting student) under the direction of Toby Stafford and Karen Smith. She is originally from Detroit, Michigan.

Walton's research is funded by the NSF.

• July, 2015

### New Faculty Member: Gillian Queisser

Dr. S. Gillian Queisser joined our department in July 2015 as Associate Professor. Dr. Queisser's research interests include numerics and scientific computing, high-performance computing, and applications to the life sciences.

Queisser's primary research goal is to move the frontiers of computation-based neuroscience toward a discipline driven by physical first principles, numerical methods and large scale simulations. Since computational methods in neuroscience are currently based on analogies, rather than detailed physical models, Queisser and his research group use and develop numerical methods for large scale computing in order to solve systems of non-linear partial differential equations. These systems define continuum-based models of three-dimensional neuronal processes on intricate morphologies. Queisser's work on numerical and computational methods has brought forth new and robust grid refinement strategies for geometric multigrid methods exposed to highly complex computational domains, adaptive grid refinement, and space/time-parallel multiscale simulation methods.

Queisser is also currently extending his interdisciplinary approach to "virtual medicine" by coupling electrical, biochemical and mechanical processes, and by developing efficient numerical methods, to help transform medical procedure from an experience-governed discipline to an optimized and individualized process.

Queisser completed his PhD thesis in 2008 at the Ruprecht-Karls University of Heidelberg. During his graduate studies he was Research Associate at the Simulation in Technology Research Group at the University of Heidelberg. From 2008 to 2010 he was Independent Research Group Leader of the Computational Neuroscience Research Group at the Cluster of Excellence CellNetworks at the University of Heidelberg. From 2010 until joining Temple, he was W-1 Professor at the Department of Computer Science and Mathematics of the Goethe University of Frankfurt.

Dr. Queisser's research has been supported by the CellNetworks Cluster of Excellence and the German Federal Ministry of Education and Research.

• July, 2015

Ahmad Sabra was awarded his PhD in mathematics on July 31, 2015. The title of his dissertation was Nonlinear partial differential equations and optical surfaces design, and his thesis advisor was Professor Cristian Gutierrez. Dr. Sabra now holds a postdoctoral research position in the Faculty of Mathematics, Infomatics, and Mechanics, Warsaw Center of Mathematics and Computer Science, University of Warsaw, Poland.

• July, 2015

### Promotion and tenure for Benjamin Seibold

Dr. Benjamin Seibold was awarded tenure and promoted to Associate Professor by the Temple University Board of Trustees, effective July 1, 2015.

• July, 2015

### Matthew Lagro awarded PhD

Matthew Lagro was awarded his PhD in mathematics on July 31, 2015. The title of his dissertation was A Perron-Frobenius type of theorem for quantum operations, and his thesis advisor was Professor Wei-Shih Yang.

• July, 2015

### David Futer co-organizer of Orsay conference

Associate Professor David Futer was co-organizer of the conference, Classical and quantum hyperbolic geometry and topology, July 6-10, 2015, in Orsay, France. The conference was in honor of the eminent geometer Francis Bonohan. Professor Futer was also a co-PI on the NSF grant supporting the conference.

• July, 2015

### Promotion and tenure for Benjamin Seibold

Dr. Benjamin Seibold was awarded tenure and promoted to Associate Professor by the Temple University Board of Trustees, effective July 1, 2015.

• July, 2015

### Daniel Szyld Editor in Chief for SIAM Journal of Matrix Analysis and Applications

Professor Daniel Szyld has been named Editor in Chief of the Society for Industrial and Applied Mathematics Journal of Matrix Analysis and Applications. This journal was ranked 22 out of 251 by Science Citation Index for applied mathematics journals worldwide, and it is the leading journal in applied and numerical linear algebra.

• August, 2015

### Shiferaw Berhanu on Scientific Committee for Brazil Workshop

Professor Shiferaw Berhanu was on the Scientific Committee for the 8th Workshop on Geometric Analysis of PDEs and Several Complex Variables, Serra Negra, Brazil, August 3-7. Professor Berhanu was also PI on an NSF conference grant supporting the workshop. Professors Berhanu, Gerardo Mendoza, and Irina Mitrea were among the main lecturers.

• August, 2015

### David Futer Named Elinor Lunder Founders' Circle Member at IAS

Associate Professor David Futer has been named Elinor Lunder Founders' Circle Member Member of the Institute for Advanced Study, Princeton, New Jersey, for the 2015-2016 academic year. He will be on leave from Temple during this time.

• August, 2015

### Ahmad Sabra at Heidelberg Laureate Forum

Dr. Ahmad Sabra (Ph.D. Temple 2015) was selected to participate as a Young Researcher at the 2015 Heidelberg Laureate Forum, August 23-28. The participating Laureates are all winners of the Abel Prize, Fields Medal, or Turing Award. The goal of the forum is to foster interaction between Laureates and Young Researchers.

• August, 2015

### Vasily Dolgushev awarded new NSF grant

Associate Professor Vasily Dolgushev was awarded a new NSF research grant, Questions on Algebraic Operads and Related Structures. From the abstract: "The principal investigator is tackling the Deligne-Drinfeld conjecture on the Grothendieck-Teichmueller Lie algebra using the deformation complex of the operad governing Gerstenhaber algebras and Kontsevich's graph complex related to deformation quantization. The PI is working on a circle of problems related to the modular operad which is obtained by applying the Feynman transform to the operad governing commutative algebras. The PI also works on the problem of deformation quantization over a graded base and studies a higher categorical structure on homotopy algebras. The study of the Grothendieck-Teichmueller Lie algebra is motivated by its links to deformation quantization, the absolute Galois group of rational numbers and the theory of motives. Questions about the Feynman transform of the operad governing commutative algebras are motivated by the study of spaces of long knots." The award amount is \$160K.

• September, 2015

### Isaac Klapper and Daniel Szyld awarded new NSF grant

Professor Isaac Klapper is PI and Professor Daniel Szyld is co-PI on the new NSF grant, Collaborative Research: Connecting Omics to Physical and Chemical Environment in Community Microbial Ecology. From the abstract: "The investigators study an important microbial community type, namely biofilms driven by photosynthesis, particularly as subaerial biofilms (subaerial biofilms are generally non-submerged microbial communities, living together in close proximity in self-secreted polymeric matrices and exposed to air) on carbonate stones. The context of the project is cultural environments, specifically microorganisms that attach to stone and grow as biofilms. These communities can discolor and degrade cultural monuments, but, at the same time, can offer useful insights into many microbial communities by providing platforms for developing and testing hypotheses of microbial ecology. Biofilms inhabiting outdoor stonework have advantages in this respect. They contain the essential biocomplexity for survival in open, uncontrolled environments, but, because of the relatively stringent conditions typical of exposed stone, still have amenable ecologies, and also are known to demonstrate mutually beneficial associations with cooperating photosynthetic and nonphotosynthetic organisms. Particularly important, their simplicity and accessibility make them well suited for use as subjects for development of prototype mathematical methodology needed for connecting omics-based cell-level metabolic models to physics-based community-level function models. The linkage of community data to community model is an essential piece, and one for which mathematics is central, in the broad program of transforming omics into useable theory of microbial communities which, in turn, is central to the program of modern microbiology. This project aims to construct multiscale population models capable of accepting omics (e.g., genomics, transcriptomics) and physical (e.g., temperature, light intensity) data at the microscale, and to develop mathematical methods for bridging the gap between community level omics and community level population models. The core target are the modes of regulation among microbial community members and how they are effected by the physical environment."

• September, 2015

### Shiferaw Berhanu named AMS Fellow

Professor Shiferaw Berhanu has been chosen to join the 2016 class of Fellows of the American Mathematical Society. He will be officially inducted at the upcoming annual Joint Mathematics Meetings, in Seattle, in January 2016. The Fellows of the American Mathematical Society program recognizes members who have made outstanding contributions to the creation, exposition, advancement, communication, and utilization of mathematics.

• November, 2015

### College teaching award for Farzana Chaudhry and college mentoring award for Martin Lorenz

Farzana Chaudhry, Assistant Professor of Instruction, was presented the Dean's Distinguished Teaching Award, and Professor Martin Lorenz was presented the Dean's Distinguished Excellence in Mentoring Award, both at the 2015 College of Science and Technology Distinguished Faculty Awards Dinner, Sunday, November 8.

• November, 2015

### New MS in Applied and Computational Mathematics

A flexible and student-centered master's degree program in applied and computational mathematics, equipping our graduates with a strong foundation on which to build their careers (or pursue further graduate studies).


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# Recurrent formula

• June 13th 2012, 06:30 AM
wabaffet
Recurrent formula
I have this kind of problem. I have to find a recurrent formula for
I(n)=integrate (tan(x))^n)dx from n=0 to a, and then I need to fine I(0) and I(1).
I wrote it like this
I(n)=int ((tan(x))^(n-1)*(tan(x)))dx and then tried to integrate it partially.

u=(tan(x))^(n-1)
du=(n-1)*((tan(x))^(n-2))/(cos(x))^2
v=int (tan(x)dx)=-log|cos(x)|
But, when I put it back...
I(n)=-tan(x)*log|cos(x)|-(n-1)*int((tan(x))^(n-2)* (log|cos(x)|/(cos(x))^2)
I have this, and I don't know what to do with this new int.
• June 13th 2012, 06:46 AM
Reckoner
Re: Recurrent formula
Quote:

Originally Posted by wabaffet
I have this kind of problem. I have to find a recurrent formula for
I(n)=integrate (tan(x))^n)dx from n=0 to a, and then I need to fine I(0) and I(1).

$I(n) = \int_0^a\tan^nx\,dx$

$I(0) = \int_0^adx$

$I(1) = \int_0^a\tan x\,dx$

You should be able to integrate those. For $n\geq2,$

$I(n) = \int_0^a\tan^2x\tan^{n-2}x\,dx$

$= \int_0^a\left(\sec^2x-1\right)\tan^{n-2}x\,dx$

$= \int_0^a\sec^2x\tan^{n-2}x\,dx - \int_0^a\tan^{n-2}x\,dx$

$= \int_0^a\sec^2x\tan^{n-2}x\,dx - I(n-2)$

Now you should be able to evaluate the integral on the left...
• June 13th 2012, 02:50 PM
wabaffet
Re: Recurrent formula
I did it, it's all ok at the end. Thank you.


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# Corrections to scaling neutrino mixing: Non-zero θ13,δCP and baryon asymmetry

Kalita, Rupam (Department of Physics, Tezpur University, Tezpur-784028, India) ; Borah, Debasish (Department of Physics, Tezpur University, Tezpur-784028, India) ; Das, Mrinal Kumar (Department of Physics, Tezpur University, Tezpur-784028, India)

12 March 2015

Abstract: We study a very specific type of neutrino mass and mixing structure based on the idea of Strong Scaling Ansatz (SSA) where the ratios of neutrino mass matrix elements belonging to two different columns are equal. There are three such possibilities, all of which are disfavored by the latest neutrino oscillation data. We focus on the specific scenario which predicts vanishing reactor mixing angle θ13 and inverted hierarchy with vanishing lightest neutrino mass. Motivated by several recent attempts to explain non-zero θ13 by incorporating corrections to a leading order neutrino mass or mixing matrix giving θ13=0 , here we study the origin of non-zero θ13 as well as leptonic Dirac CP phase δCP by incorporating two different corrections to scaling neutrino mass and mixing: one, where type II seesaw acts as a correction to scaling neutrino mass matrix and the other, with charged lepton correction to scaling neutrino mixing. Although scaling neutrino mass matrix originating from type I seesaw predicts inverted hierarchy, the total neutrino mass matrix after type II seesaw correction can give rise to either normal or inverted hierarchy. However, charged lepton corrections do not disturb the inverted hierarchy prediction of scaling neutrino mass matrix. We further discriminate between neutrino hierarchies, different choices of lightest neutrino mass and Dirac CP phase by calculating baryon asymmetry and comparing with the observations made by the Planck experiment.

Published in: Nuclear Physics B 894 (2015) 307-327


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# How Much Does the Radiation Pattern of an “EFHW” Antenna System Vary Across its Bands?

This NEC4.2 analysis shows one example of such variation.

              **RADIATION ENVELOPE at 3.9MHz**


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## Bulletin of the Belgian Mathematical Society - Simon Stevin

### On the mathematical work of Jean Schmets

#### Abstract

In the introductory Section 0. some of the most important points in the professional curriculum vitae of Jean Schmets are given. Then Section 1 is devoted to present (part of) the work for which Schmets was very well known until 1990: He has been the leading specialist in the world for locally convex spaces $C(X)$ of continuous functions with various topologies and for the corresponding spaces $C(X,E)$ of vector valued continuous functions. Finally, in Section 2 some results which Schmets obtained in cooperation with Manuel Valdivia since 1990 are reviewed: work on domains of real analytic existence, continuous linear right inverses for $C^\infty$- functions and Whitney extensions for non quasianalytic functions.

#### Article information

Source
Bull. Belg. Math. Soc. Simon Stevin, Volume 14, Number 3 (2007), 385-405.

Dates
First available in Project Euclid: 28 September 2007

https://projecteuclid.org/euclid.bbms/1190994201

Digital Object Identifier
doi:10.36045/bbms/1190994201

Mathematical Reviews number (MathSciNet)
MR2387037

Zentralblatt MATH identifier
1161.01019

#### Citation

Bierstedt, Klaus D.; Bonet, José. On the mathematical work of Jean Schmets. Bull. Belg. Math. Soc. Simon Stevin 14 (2007), no. 3, 385--405. doi:10.36045/bbms/1190994201. https://projecteuclid.org/euclid.bbms/1190994201


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# boundary point of a set

But that doesn't not imply that a limit point is a boundary point as a limit point can also be a interior point . In Theorem 2.5, A(f) is a boundary point of K only if all points f(x) not in a negligible set of x belong to the intersection of K with one of its hyperplanes of support. The set A in this case must be the convex hull of B. For example, the term frontier has been used to describe the residue of S, namely S \ S (the set of boundary points not in S). ;�n{>ֵ�Wq���*$B�N�/r��,�?q]T�9G� ���>^/a��U3��ij������>&KF�A.I��U��o�v��i�ֵe��Ѣ���Xݭ>�(�Ex��j^��x��-q�xZ���u�~o:��n޾�����^�U_���k��oN�$��o��G�[�ϫ�{z�O�2��r��)A�������}�����Ze�M�^x �%�Ғ�fX�8���^�ʀmx���|��M\7x�;�ŏ�G�Bw��@|����N�mdu5�O�:�����z%{�7� All content on this website, including dictionary, thesaurus, literature, geography, and other reference data is for informational purposes only. If is either an interior point or a boundary point, then it is called a limit point (or accumulation point) of . v8 ��_7��=p In topology and mathematics in general, the boundary of a subset S of a topological space X is the set of points which can be approached both from S and from the outside of S. More precisely, it is the set of points in the closure of S not belonging to the interior of S. An element of the boundary of S is called a boundary point of S. The term boundary operation refers to finding or taking the boundary of a set. Practice Exercise 1G 1 Practice Exercise 1G Ralph Joshua P. Macarasig MATH 90.1 A Show that a boundary point of a set is either a limit point or an isolated point of the set. �f8^ �wX���U1��uBU�j F��:~��/�?Coy�;d7@^~ �"�MA�: �����!�������6��%��b�"p������2&��"z�ƣ��v�l_���n���1��O9;�|]G�@{2�n�������� ���1���_ AwI�Q�|����8k̀���DQR�iS�[\������=��D��dW1�I�g�M{�IQ�r�$��ȉ�����t��}n�qP��A�ao2e�8!���,�^T��9������I����E��Ƭ�i��RJ,Sy�f����1M�?w�W;�k�U��I�YVAב1�4ОQn�C>��_��I�$����_����8�)�%���Ĥ�ûY~tb��أR�4 %�=�������^�2��� The set of all boundary points of a set forms its boundary. Boundary point of a set Ask for details ; Follow Report by Smeen02 08.09.2019 Log in to add a comment stream @z8�W ����0�d��H�0wu�xh׬�]�ݵ$Vs��-�pT��Z���� The points (x(k),y(k)) form the boundary. stream 8��P���.�Jτ�z��YAl�$,��ԃ�.DO�[��!�3�B鏀1t�S��*! https://goo.gl/JQ8Nys Finding the Interior, Exterior, and Boundary of a Set Topology The set of all boundary points of a set $$A$$ is called the boundary of $$A$$ or the frontier of $$A$$. Theorem: A set A ⊂ X is closed in X iﬀ A contains all of its boundary points. Now as we also know it's equivalent definition that s will be a closed set if it contains all it limit point. And we call $\Bbb{S}$ a closed set if it contains all it's boundary points. �g�2��R��v��|��If0к�n140�#�4*��[J�¬M�td�hV5j�="z��0�c$�B�4p�Zr�W�u �6W�$;��q��Bش�O��cYR���$d��u�ӱz̔b�.��(�$$��GJBJ�͹]���8*+q۾��l��8��;����x3���n����;֨S[v�%:�a�m�� �t����ܧf-gi,�]�ܧ�� T*Cel**���J��\2\�l=�/���q L����T���I)3��Ue���:>*���.U��Z�6g�춧��hZ�vp���p! 5 0 obj Let's check the proof. ,�Z���L�Ȧ�2r%n]#��W��\j��7��h�U������5�㹶b)�cG��U���P���e�-��[��Ժ�s��� vc1XV�,^eFk It's fairly common to think of open sets as sets which do not contain their boundary, and closed sets as sets which do contain their boundary. <> Viewed 568 times 2. endobj Chords are drawn from each boundary point to every other boundary point. T��h-�)�74ս�_�^��U�)_XZK����� e�Ar �V�/��ٙʂNU��|���!b��|1��i!X��͡.��B�pS(��ۛ�B��",��Mɡ�����N���͢��d>��e\{z�;�{��>�P��'ꗂ�KL ��,�TH�lm=�F�r/)bB&�Z��g9�6ӂ��x�]䂦̻u:��ei)�'Nc4B Here is some Python code that computes the alpha-shape (concave hull) and keeps only the outer boundary. A point not in the set which is not a boundary point is called exterior point. \(D$$ is said to be open if any point in $$D$$ is an interior point and it is closed if its boundary $$\partial D$$ is contained in $$D$$; the closure of D is the union of $$D$$ and its boundary: Set N of all natural numbers: No interior point. Examples: (1) The boundary points of the interior of a circle are the points of the circle. ���ؽ}:>U5������Dz�{�-��հ���q�%\"�����PQ�oK��="�hD��K=�9���_m�ژɥ��2�Sy%�_@��Rj8a���=��Nd(v.��/���Y�y2+� 3) Show that a point x is an accumulation point of a set E if and only if for every > 0 there are at least two points belonging to the set E (x - ,x + ). 35 0 obj %PDF-1.4 Proof: By definition, is a boundary point of a set if every neighborhood of contains at least one point in and one point in.Let be a boundary point of. x��\˓7��BU�����D�!T%$$�Tf)�0��:�M�]�q^��t�1ji4�=vM8P>xv>�Fju��׭�|y�&~��_�������������s~���ꋳ/�x������\�����[�����g�w�33i=�=����n��\����OJ����ޟG91g����LBJ#�=k��G5 ǜ~5�cj�wlҌ9��JO���7������>ƹWF�@e,f0���)c'�4�*�d����J;�A�Bh���O��j.Q�q�ǭ���y���j��� 6x����y����w6�ݖ^�����߃fb��V�O� Note that . Each row of k defines a triangle in terms of the point indices, and the triangles collectively form a bounding polyhedron. If is a subset of , then a point is a boundary point of if every neighborhood of contains at least one point in and at least one point not in . This information should not be considered complete, up to date, and is not intended to be used in place of a visit, consultation, or advice of a legal, medical, or any other professional. Definition 5.1.5: Boundary, Accumulation, Interior, and Isolated Points : Let S be an arbitrary set in the real line R. A point b R is called boundary point of S if every non-empty neighborhood of b intersects S and the complement of S. The set of all boundary points of S is called the boundary of S, denoted by bd(S). Whole of N is its boundary, Its complement is the set of its exterior points (In the metric space R). The set of interior points in D constitutes its interior, $$\mathrm{int}(D)$$, and the set of boundary points its boundary, $$\partial D$$. ��c{?����J�=� �V8i�뙰��vz��,��b�t���nz��(��C����GW�'#���b� Kӿgz ��ǆ+)�p*� �y��œˋ�/ a point each of whose neighborhoods contains points of the set as well as points not in the set. A (symmetrical) boundary set of radius r and center x_0 is the set of all points x such that |x-x_0|=r. Given a set of N-dimensional point D (each point is represented by an N-dimensional coordinate), are there any ways to find a boundary surface that enclose these points? Some authors (for example Willard, in General Topology) use the term frontier instead of boundary in an attempt to avoid confusion with a different definition used in algebraic topology and the theory of manifolds. A point of the set which is not a boundary point is called interior point. First, we consider that. Ask Question Asked 5 years, 1 month ago. �x'��T "| �o�; BwE�Ǿ�I5jI.wZ�G8��悾fԙt�r�A�n����l��Q�c�y� &%����< 啢YW#÷�/s!p�]��B"*�|uΠ����:Y:�|1G�*Nm�F�p�mWŁ8����;k�sC�G Let x_0 be the origin. Then, suppose is not a limit point. Notations used for boundary of a set S include bd(S), fr(S), and$${\displaystyle \partial S}$$. No, a boundary point may not be an accumulation point.Since an isolated point has a neighbourhood containing no other points of the set, it's not an interior point. This video shows how to find the boundary point of an inequality. Examples: (1) The boundary points of the interior of a circle are the points of the circle. Similarly, point B is an exterior point. This video shows how to find the boundary point of an inequality. 5. A set which contains no boundary points – and thus coincides with its interior, i.e., the set of its interior points – is called open. So formally speaking, the answer is: B has this property if and only if the boundary of conv(B) equals B. Example: The set {1,2,3,4,5} has no boundary points when viewed as a subset of the integers; on the other hand, when viewed as a subset of R, every element of the set is a boundary point. Proof. Interior, closure, and boundary We wish to develop some basic geometric concepts in metric spaces which make precise certain intuitive ideas centered on the themes of \interior" and \boundary" of a subset of a metric space. Boundary Point. A point b R is called boundary point of S if every non-empty neighborhood of b intersects S and the complement of S. The set of all boundary points of S is called the boundary of S, denoted by bd(S). �KkG�h&%Hi_���_��ԗ�E��%�S�@����.g���Ġ J#��,DY�Y�Y���v�5���zJv�v�� zw{����g�|� �Dk8�H���Ds�;��K�h�������9;]���{�S�2�)o�'1�u�;ŝ�����c�&��̌L��;)a�wL��������HG Note the diﬀerence between a boundary point and an accumulation point. 6 0 obj The boundary of A, @A is the collection of boundary points. %�쏢 > ��'���5W|��GF���=�:���4uh��3���?R�{�|���P�~�Z�C����� Plane partitioning Definition 7 (Hole Boundary Points (HBP)): HBPs are the intersection points of nodes' sensing discs around a coverage hole, which develop an irregular polygon by connecting adjacent points. A set A is said to be bounded if it is contained in B r(0) for some r < 1, otherwise the set is unbounded. Set Q of all rationals: No interior points. For 3-D problems, k is a triangulation matrix of size mtri-by-3, where mtri is the number of triangular facets on the boundary. In R^3, the boundary The trouble here lies in defining the word 'boundary.' {1\n : n $$\displaystyle \in$$ N} is the bd = (0, 1)? In the case of open sets, that is, sets in which each point has a neighborhood contained within the set, the boundary points do not belong to the set. A point which is a member of the set closure of a given set and the set closure of its complement set. The set of all boundary points of a set forms its boundary. For 2-D problems, k is a column vector of point indices representing the sequence of points around the boundary, which is a polygon. �v\��?�9�o��@��x�NȰs>EU����H5=���RZ==���;�cnR�R*�~3ﭴ�b�st8������6����Ζm��E��]��":���W� For example, 0 and are boundary … (2) The points in space not on a given line form a region for which all points of the line are boundary points: the line is the boundary of the region. from scipy.spatial import Delaunay import numpy as np def alpha_shape(points, alpha, only_outer=True): """ Compute the alpha shape (concave hull) of a set of points. Point C is a boundary point because whatever the radius the corresponding open ball will contain some interior points and some exterior points. Please Subscribe here, thank you!!! A boundary point may or may not belong to the set. �v��Kl�F�-�����Ɲ�Wendstream It is denoted by$${F_r}\left( A \right)$$. boundary point of S if and only if every neighborhood of P has at least a point in common with S and a point Point A is an interior point of the shaded area since one can find an open disk that is contained in the shaded area. If is a subset of , then a point is a boundary point of if every neighborhood of contains at least one point in and at least one point not in . In the case of open sets, that is, sets in which each point has a neighborhood contained within the set, the boundary points do not belong to the set. A point s S is called interior point of S if there exists a neighborhood of … How to get the boundary of a set of points? 2) Show that every accumulation point of a set that does not itself belong to the set must be a boundary point of that set. .���bb�m����CP�c�{�P�q�g>��.5� 99�x|�=�NX �ዜg���^4)������ϱ���x9���3��,P��d������w+51�灢'�8���q"W^���)Pt>|�+����-/x9���ȳ�� ��uy�no������-��Xڦ�L�;s��(T�^�f����]�����A)�x�(k��Û ����=��d��;'3Q �7~�79�T�{?� ��|U�.�un|?,��Y�j���3�V��?�{oԠ�A@��Z�D#[NGOd���. Unlike the convex hull, the boundary can shrink towards the interior of the hull to envelop the points. x��ZK���o|�!�r�2Y|�A�e'���I���J���WN���+>�dO�쬐�0������W_}�я;)�N�������>��/�R��v_��?^�4|W�\��=�Ĕ�##|�jwy��^z%�ny��R� nG2�@nw���ӟ��:��C���L�͘O��r��yOBI���*?��ӛ��&�T_��o�Q+�t��j���n$�>`@4�E3��D��� �n���q���Ea��޵o��H5���)��O网ZD For the case of , the boundary points are the endpoints of intervals. Note S is the boundary of all four of B, D, H and itself. In R^2, the boundary set is a circle. A point which is a member of the set closure of a given set and the set closure of its complement set. Despite widespread acceptance of the meaning of the terms boundary and frontier, they have sometimes been used to refer to other sets. The set A is closed, if and only if, it contains its boundary, and is open, if and only if A\@A = ;. <> The boundary is, by definition , A\intA & hence an isolated point is regarded as a boundary point. endobj In R^1, the boundary set is then the pair of points x=r and x=-r. Math 396. The set of all limit points of is a closed set called the closure of , and it is denoted by . k = boundary(x,y) returns a vector of point indices representing a single conforming 2-D boundary around the points (x,y). Active 5 years, 1 month ago. https://encyclopedia2.thefreedictionary.com/Boundary+Point+of+a+Set, Dictionary, Encyclopedia and Thesaurus - The Free Dictionary, the webmaster's page for free fun content, Boundary Range Expeditionary Vehicle Trials Ongoing. This is probably what matlab's boundary does inside. what is the boundary of this set? 2599 ɓ-�� _�0a�Nj�j[��6T��Vnk�0��u6!Î�/�u���A7� Felix Hausdorff named the intersection of S with its boundary the border of S (the term boundary is used to refer to this set in Metric Spaces by E. T. Copson). question, does every set have a boundary point? Given a set S and a point P (which may not necessarily be in S itself), then P is a boundary point of S if and only if every neighborhood of P has at least a point in common with S and a point not in S. For example, in the picture below, if the bluish-green area represents a set S, then the set of boundary points of S form the darker blue outlines. If A(f) is a boundary point of K, then passing through it there exists a hyperplane of support π: ℓ(z) + c = 0 of K; say ℓ(z) + c ≥ 0 for z in K. Theorem: a set forms its boundary points of the set closure of a are. Be the convex hull, the boundary 's boundary does inside is for informational purposes only the set of. The word 'boundary. how to find the boundary points what matlab 's does... Indices, and the set closure of, and it is denoted by collectively form bounding! The trouble here lies in defining the word 'boundary. case of and... ) the boundary points of the interior of the set closure of, boundary! Bd = ( 0, 1 ) the boundary points a boundary point may or may not belong the! Find an open disk that is contained in the set of all rationals: No interior point area one. 'S boundary does inside Question Asked 5 years, 1 ) the boundary points are the points ( the. Since one can find an open disk that is contained in the metric space R ) content on this,! Does every set have a boundary point the boundary set is a closed if! Iﬀ a contains all of its complement set } \left ( a \right ) $! Points not in the set closure of its complement set interior of a a! 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## Seminars and Colloquia by Series

Wednesday, November 7, 2018 - 12:20 , Location: Skiles 005 , Federico Bonetto , Georgia Tech , Organizer: Trevor Gunn
Wednesday, November 7, 2018 - 10:14 , Location: Skiles 005 , Kelly Bickel , Bucknell University , Organizer: Shahaf Nitzan
Series: PDE Seminar
Tuesday, November 6, 2018 - 15:00 , Location: Skiles 006 , Assistant Professor , University of Minnesota , , Organizer: Xukai Yan
Monday, November 5, 2018 - 14:00 , Location: Skiles 006 , Min Hoon Kim , Korea Institute for Advanced Study , Organizer: Jennifer Hom
The still open topological 4-dimensional surgery conjecture is equivalent to the statement that all good boundary links are freely slice. In this talk, I will show that every good boundary link with a pair of derivative links on a Seifert surface satisfying a homotopically trivial plus assumption is freely slice. This subsumes all previously known methods for freely slicing good boundary links with two or more components, and provides new freely slice links. This is joint work with Jae Choon Cha and Mark Powell.
Monday, November 5, 2018 - 13:00 , Location: Skiles 006 , Min Hoon Kim , Korea Institute for Advanced Study , Organizer: Jennifer Hom
In 1982, by using his celebrated disk embedding theorem, Freedman classified simply connected topological 4-manifolds up to homeomorphism. The disk embedding conjecture says that the disk embedding theorem holds for general 4-manifolds with arbitrary fundamental groups. The conjecture is a central open question in 4-manifold topology. In this introductory survey talk, I will briefly discuss Freedman's disk embedding conjecture and some related conjectures (the topological 4-dimensional surgery conjecture and the s-cobordism conjecture). I will also explain why the disk embedding conjecture implies that all good boundary links are freely slice.
Friday, November 2, 2018 - 15:00 , Location: Skiles 005 , , Louisiana State University , Organizer: Lutz Warnke
Thursday, November 1, 2018 - 15:05 , Location: Skiles 006 , Christian Houdré , Georgia Institute of Technology , Organizer: Christian Houdre
Wednesday, October 31, 2018 - 13:55 , Location: Skiles 005 , , UGA , , Organizer: Galyna Livshyts
TBA
Wednesday, October 31, 2018 - 12:55 , Location: Skiles 006 , , UGA , , Organizer: Galyna Livshyts
TBA
Wednesday, October 31, 2018 - 12:20 , Location: Skiles 005 , Haomin Zhou , Georgia Tech , Organizer: Trevor Gunn