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ISSN : 1598-6721(Print)
ISSN : 2288-0771(Online)
The Korean Society of Manufacturing Process Engineers Vol.16 No.2 pp.1-6
DOI : https://doi.org/10.14775/ksmpe.2017.16.2.001

# A Study on the Design and Performance Test of Side Thruster

Hyeong-Min Kim*, Lae-Sung Kim**, Sung-Hyun Cho*, Sung-Ki Lyu*#
*Department of Mechanical System Engineering, ERI, Gyeongsang National University
**Creative Aero-IT-Mech Convergence Eng. Education Program, Gyeongsang National University
Corresponding Author : sklyu@gnu.ac.kr+82-55-772-1632, +82-55-772-1578
March 8, 2017 March 13, 2017 March 18, 2017

## Abstract

In this paper, we present a study concerning the design of a 400 N class side thruster for small ships. The side thrusters used in Korea are imported from abroad. The performance and durability of the imported products employed in Korea are not adequate, therefore the side thrusters which will be suitable for Korean domestic needs to be re-designed.

The strength calculation of the side thruster was performed by KS standard. Strength calculation and design were made to meet design requirements. Structural analysis and safety factor analysis were carried out to confirm the validity of strength calculations and design. After manufacturing the bevel gear, a back lash test was conducted. We also conducted a no-load test, a rated load, and an overload test for a performance test and a durability test of the design while satisfying the design conditions.

# 사이드 스러스터 설계 및 성능평가에 관한 연구

김 형민*, 김 래성**, 조 성현*, 류 성기*#
*경상대학교 기계시스템공학과, 공학연구원,
**경상대학교 항공IT기계융합사업단

## 초록

C0396466-2016-0553

© The Korean Society of Manufacturing Process Engineers

This is an Open-Access article distributed under the terms of the Creative Commons Attribution-Noncommercial 3.0 License (CC BY-NC 3.0 http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

## 1.Introduction

A side thruster is a mechanical device used as auxiliary power for entering and exiting ports which are installed at the bottom of the ship, in the case of small boats (fishing boats), all of these devices are imported from abroad. Since side thrusters are installed and used in small domestic vessels, users’ request for improvement is increased, so our research continues.[1-5] The imported side thrusters are difficult to use in Korea in consideration of the price, performance and function. Users are demanding better performance and more variety choices. Korea users do not use the side thruster only when entering and exiting ports. Currently, the use of auxiliary equipment for operation and fishery work is universal, such as the role of ship grabbing a certain position by the ocean current when fishing and working by gradually moving the ship to the side. Along with changes in the size and working environment of small domestic vessels (fishing boats), we designed the side thruster with suitable thrust for the users’ working condition. We set the validation test based on the technical design of the side thruster and performed the backlash test, rated output test and maximum output test to make the target value and considering if meet the design specification.

## 2.Design and Modeling of Side Thruster

The thrust class of the side thruster was chosen as 400N, and the side thruster configuration and development specification are shown in Fig. 1 and Table 1. The side thruster is made up of parts such as a hydraulic motor, a coupling which connects the hydraulic motor and the input shaft, input shaft, bevel gear, output shaft, power transmission source to the propeller, and case, case cover, tunnel, and protective cover and so on.

Table 2 shows the material and the minimum diameter for calculating the strength of the input and output shaft used in the design product. Shaft strength calculation was performed by selecting the most fragile part (minimum diameter).

The input shaft diameter (d0) of the side thruster is calculated by equation (1) and must be greater than or equal to the calculated value.

(1)

P : Shaft output at the continuous maximum output of system [kW]

n : Rotating speed during continuous rotation of the shaft [rpm]

F : Coefficient according to the type of thruster

T0 : Material design tensile strength [N/mm2]

K1 : Coefficient of shaft design characteristics, the value stipulated by Korea Ship Safety Technology Authority(KST) was applied.[6-9]

Since the calculated input shaft minimum diameter is 32.0 mm, the calculated value is satisfied with the design specification because it is larger than the minimum diameter of the design input shaft.

The diameter of the output shaft (dP) is calculated by the formula (2) and must be not less than the calculated value.

$d 0 = 100 K 2 H R ⋅ 560 T p + 160 ⋅ 1 1 − d i / d 0 4 3$
(2)

H : Shaft output at the continuous maximum output of system [kW]

R : Rotating speed at continuous maximum output of shaft [rpm]

di : Inner diameter of hollow shaft [mm]

do : Actual outer diameter of hollow shaft [mm]

Tp : Material design tensile strength [N/mm2]

K2 : Coefficient of shaft design characteristics

Calculating the strength of output shaft by the equation (2), since the minimum diameter of the output shaft is 35.0 mm and larger than the calculated value, so the design condition is satisfied. As shown in Fig. 2, building the 3D modeling of the side thruster through the design such as side thruster input and output shaft strength calculation.

## 3.Structural Analysis and Discussion

Analysis data confirms the deformation of the side thruster system due to the thrust of the side thruster when the side thruster is mounted on the actual ship and confirms the deformation of the tunnel and the stability of the assembled bolt, proceeding structural analysis to prevent leakage of ships.

### 3.1.Material Selection

In Table 3, the physical property values of each material can be confirmed, and the physical properties of each material are entered into the modeling of parts. Since the physical property values which input to the simulation material may influence the analysis result greatly, so the real physical property values presented at Korea Standards Association were used. Moreover, for the tunnel, material property values provided by Hankuk Fiber were applied[10]. Table 4.

The load condition is the output thrust from the side thruster to the main body of the thruster and was calculated as 400N.

Also, the assessed moment values were given to two loads, one load which is received in shaft vertical direction and one load which is received in the rotation direction when the shaft rotated. Tabel 4 shows the calculated values of the moment which input to the load condition.

### 3.3.Results and Discussion

As shown in Table 5, the analysis result demonstrates the deformation at each part, and the load applied to each assembled bolt. Based on the analysis result, the deformation of the tunnel is within 1mm maximum, and the safty factor of assembled bolt is more than 1, so it is judged that there is no major problem in structural stability. Also, the maximum deformation among the tunnel, case, and bolt is 0.163 from the case, the minimum value of the safety factor is 1.41, so it is judged to meet the design standard.

Fig. 3 and Fig. 4 shows the displacement and safety factor by the site as a result of structural analysis. Analysis conditions and results are shown in the figure that can be easily confirmed. Since the thrust generated by the load direction of each assembled bolt, the rotation direction of the side thruster, and the rotation of the side thruster output part, input the load value which the side thruster main body received and confirm displacement and safety factor.

## 4.Test Results and Discussion

### 4.1.Backlash Test Results and Discussion

Measuring the cylindrical backlash to check the clearance occurs when the bevel gear assembled on the input and output shaft of side thruster, also for checking the interference between gears when meshing and rotating, and the space between tooth surfaces. Proceeding the test with the backlash measuring device as Fig. 5. First, fixing output shaft (a), using the measuring plate which in input shaft spline part (b) and indicator (c) to measure the three points at 120°. The design standard of backlash was 0.2 ~ 0.3 mm. According to the test procedure and testing three specimens to confirm the backlash.

Table 6 summarizes the backlash test results, and the average of backlash was found to be 0.232 mm.

### 4.2.No Load Output Test Results and Discussion

The no-load output test is to check the output side rotation without any load of the hydraulic motor and the temperature variation of side thruster, comparing to the input flow rate of the hydraulic motor, measuring the rotation of output shaft and the surface temperature of thruster every 10 minutes. When inputting the rated flow rate of 122.7 ℓ/min, the thruster output rotation should be measured at 1,450 rpm.

Moreover, the temperature variation after 10 minutes should not be over 10 °C. Fig. 6 is a test apparatus for the no load test, using the electric motor as the power source, rotate the hydraulic pump and input the required flow rate. The motor rotates according to the oil flows from the pump. When inputting a flow rate of 122.7 ℓ/min, the motor rotated at 1,726 rpm, and the output was 1,450 rpm due to the ratio of the bevel gear (1.19:1).

Measuring the temperature of the side thruster during the no load test means that the frictional heat of the bearing and gear by press fitting when the side thruster rotates to be confirmed. Table 7 shows the results of the no load test, the rotation output was 1,400 rpm when inputting a 122.7 ℓ/min flow rate.

### 4.3.Rated Load Output Test Results and Discussion

In the rated load output test, when the side thruster is mounted on the actual ship and operates, the propeller receives a load while rotating, so that a charge corresponding to 100% of the load is artificially was added.

We confirmed that the problem and the target performance of 1,450 rpm rotation occurred on the output side and tested to see if there was an issue in the side thruster during 25 hours. So when 100% load is applied to the output shaft, confirm if the output rotation is meet the target performance. When the output shaft drives the side thruster, the hydraulic pump connected to the suction line which is attached to the output shaft applied a 10 MPa (100 kgf/cm2) pressure.

Table 8 shows the results of rated output test with a testing side thruster. Through the trial, we found the output rotation is maintained at an average of 1,426 rpm, and confirmed there was no abnormality in the durability of side thruster.

### 4.4.Overload Output Test Results and Discussion

Overload test is a test to check the durability of the side thruster at the same rotation of rated load test by adding a 120% load on the output side. In this test, applying a 21 MPa (210 kgf/cm2) pressure to the output side and operating for 25 hours. At this time, whether the target performance of the production side was 1,450 rpm can be confirmed. The rated load test apparatus as shown in Fig. 6 also used in overload test.

Table 8 shows the results of overload output test with a testing side thruster. Through the trial, we found that the output rotation is maintained at an average of 1,247 rpm, and confirmed there was no abnormality in the durability of side thruster. Table 9.

## 5.Conclusion

In this research, we conducted a test to demonstrate the target value based on the technical design of the 400N class side thruster. As a result of screening and considering the backlash, the rated output, and the maximum output, the following conclusions were obtained.

1. The strength calculation result of side thruster input and output shaft meet the design condition of KS standard.

2. Backlash appeared 0.24, 0.237, 0.22 mm at each of the three points according to the backlash test, and meet the design condition. As a result of analyzing the deformation and safety factor when applying rated thrust to thruster by structural analysis, it was judged to safe at a safety factor 15 maximum and 1.13 minimum.

3. The output rotational speed was 1,426 rpm when inputting a 122.7 ℓ/min flow rate via rated load test, and the output rotational speed was 1,247rpm when inputting a 122.7 ℓ/min flow rate via the overload test, so meet the design condition.

## Acknowledgement

This work was financially supported by the Small and Medium Business Administration (Grant No: C0396466-2016-0553)

## Figure

Configuration of side thruster

3D modeling of the side thruster case

Results of displacement for casing

Results of stress analysis for casing

Backlash measurement apparatus

## Table

Development specification

Shaft specification

List of the material properties

Moment acting on the side thruster

Structural analysis results of the side thruster

Backlash measurement test result

Regular test results


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# Math Help - solving polynomials

1. ## solving polynomials

How would I solve and equations like it: $d^3 - \frac{1}{d} = 5.6023$ without graphing calcs.

I am working on finding the diameters of hollow shafts when given allowable stresses and I wind up with these eqautions.

Thanks for any help.

2. That's not a polynomial, it doesn't have positive integer exponents (because $\frac{1}{d} = d^{-1}$)

Otherwise I have no idea how to solve this, I just wanted to point that out.

3. ## unsimplified

$d^4 - 5.6023d - 1 = 0$

4. I dunno if it is actually possible in an easy way ... you can't reduce the polynomial and it's a 4th degree one ... hard ... you may need to apply Ferrari's or Euler's method to do that !

5. In general, there is no easy way to solve polynomials. The polynomial here is a quartic, which can be solved (although not easily) following the approach found here:
Quartic function - Wikipedia, the free encyclopedia

A similar approach can solve quintics (polynomials of degree 5) but there is no general method for solving higher order polynomials

6. Linear and quadratics are easy because mathematicians have found a highly efficient and easy way to solve them. Cubic polynomials are quite harder (but still solvable in most situations), quartics get hard and quintics even harder (wanna try elliptic curves ?). And for higher degree ... well badgerigar sait it all

format: plain


text:
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The Gaussian Distribution: limitations qA lot of parameters to estimate !+, de,-: structured approximation (e.g., diagonal variance matrix) qMaximum likelihood estimators are not robust to outliers: Student’s t-distribution (bottom left) qNot able to describe periodic data: von Mises distribution Y = X 1 +X 2,X 1 ⊥ X 2 ⇒ µ Y = µ 1 +µ 2, Σ Y = Σ 1 +Σ 2 The multiplication of two gaussian functions is another gaussian function (although no longer normalized). $f(x,\mu,\sigma) = \frac{1}{\sigma\sqrt{2\pi}}e^\frac{-(x-\mu)^2}{2\sigma^2}$ The peak of the graph is always located at the mean and the area under the … Scroll Prev Top Next More: Statistical tests analyze a particular set of data to make more general conclusions. We calculated the Gaussian P(x) using the formula given above, and we plotted P(x) to produce a curve that is a continuous mathematical representation of the distribution of measured sensor voltages. 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Is there a division algorithm for any Euclidean Domain?

Any Euclidean domain satisfies the division “algorithm”:

For any $x,d$ there exists $q,r$ such that $x = qd+r$ with $\sigma(r)<\sigma(d)$ or $\sigma(r)=0$

With $\sigma$ a “size function.”

I’m wondering if what I would call an algorithm (i.e. a discrete series of steps to get to an answer) exists for division. Specifically:

Suppose +, -, and * are defined in some Euclidean Domain. Is there a mechanism to find $x/y$ (beyond brute force)?

Repeated subtraction works in the integers, but not the polynomials, and this was my first thought. (I realize that I’m ignoring the problem of how to do subtraction in the ring, which is quite similar.)

Solutions Collecting From Web of "Is there a division algorithm for any Euclidean Domain?"

Various complexity results are known about Euclidean domains. For example, Downey and Kach: Euclidean functions of computable Euclidean domains shows that there is a computable Euclidean domain having no (finite or transfinitely-valued) computable Euclidean function. Further there is a computable Euclidean domain with a computable Euclidean function but whose units are noncomputable, and there is a computable Euclidean domain with neither computable units nor a computable Euclidean function. See the paper and its references for much more.


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# Section-1: Critical Path Solved QuestionLogical Reasoning Discussion

Common Information

There are seven cities P, Q, R, S, T, U, and V. The table below shows all the possible direct routes to and fro between any two of the cities. It also gives both the Air as well as the Land route distances (in miles) between those cities and the time required (in hrs) for the respective journeys. A person on any one of the above seven places can travel to any one of the remaining 6 places using Air or Land route only. The person can change his/her mode of transport (Air/Land) at any of the above seven places.

Table below can be scrolled horizontally

Direct
Routes
Air Distance
(in miles)
Air Time
(in hrs)
Land Distance
(in miles)
Land Time
(in hrs)
P – Q 1100 3 900 6
P – S 2200 6 2400 10
P – R 700 2 1000 6
Q – U 1800 5 2200 11
Q – T 800 3 1100 6
R – T 1000 3 1400 10
S – T 800 3 1000 5
S – V 2200 6 2800 14
T – V 2200 6 3000 15
U – V 800 4 1200 6
 Q. Common Information Question: 3/4 If the air route and the land route fares are $\$$35 and \$$25 respectively per 100 miles for a passenger, which is the cheapest route from Q to S via R?  ✖ A. QTRPS by Land ✖ B. QPRTS by Air ✔ C. QPRTS by Land ✖ D. Both (A) and (B) ✖ E. None of these Solution: Option(C) is correct Total fare = Route distance$\times$Fare per mile ∴ The fares for the given routes can be calculated as follows: QPRTS by Air$= (1100 + 700 + 1000 + 800) \times \dfrac{35}{100}= \$1260$

QPRTS by Land $= (900 + 1000 + 1400 + 1000) \times \dfrac{25}{100}$ $= \$ 1075$QTRPS by Land$= (1100 + 1400 + 1000 + 2400) \times \dfrac{25}{100}= \$1475$

Hence, option C is the correct choice.


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# Equivalent dose

Graphic showing relationship of SI radiation dose units

The equivalent absorbed radiation dose, usually shortened to equivalent dose, or formerly dose equivalent, is a computed average measure of the radiation absorbed by a fixed mass of biological tissue, that attempts to account for the different biological damage potential of different types of ionizing radiation. It is therefore a less fundamental quantity than the total radiation energy absorbed per mass (the absorbed dose), but is a more significant quantity for assessing the health risk of radiation exposure.

It is adequate for assessing risk due to external radiation fields that penetrate uniformly through the whole body, but needs further corrections when the field is applied only to part(s) of the body or when it is due to an internal source. A further quantity called effective dose can be calculated if the fractionation of radiation to different parts of the body is known, to take into account the varying sensitivity of different organs to radiation. Another quantity called committed dose is used when the radiation source has entered the body.

Equivalent dose is dimensionally a quantity of energy per unit of mass, and is measured in sieverts or rems.

## Computation

Radiation weighting factors WR (formerly termed Q factor)
used to represent relative biological effectiveness
according to ICRP report 103[1]
x-rays, gamma rays,
beta particles, muons
1
neutrons < 1 MeV 2.5 + 18.2·e-[ln(E)]²/6
1 MeV - 50 MeV 5.0 + 17.0·e-[ln(2·E)]²/6
> 50 MeV 2.5 + 3.25·e-[ln(0.04·E)]²/6
protons, charged pions   2
alpha particles,
Nuclear fission products,
heavy nuclei
20

The equivalent dose is calculated by multiplying the absorbed energy, averaged by mass over an organ or tissue of interest, by a radiation weighting factor appropriate to the type and energy of radiation. To obtain the equivalent dose for a mix of radiation types and energies, a sum is taken over all types of radiation energy dose.[1]

$H_T = \sum_R W_R \cdot D_{T,R}\$

where

HT is the equivalent dose absorbed by tissue T
DT,R is the absorbed dose in tissue T by radiation type R
WR is the radiation weighting factor defined by regulation

Thus for example, an absorbed dose of 1 Gy by alpha particles will lead to an equivalent dose of 20 Sv.

The radiation weighting factor for neutrons has been revised over time and remains controversial.

The radiation weighting factor represents the relative biological effectiveness of the radiation. It aims to correct the simple deposited energy of the radiation (a fundamental quantity with clear physical meaning) for different biological effect of different types of radiation. An equivalent dose of radiation is estimated to have the same biological effect as an equal amount of absorbed dose of gamma rays.

If the equivalent dose is uniform throughout the organism, it will be equal to the effective dose. Otherwise, a weighted average of HT will have to be taken to average out the radiation dose through the body while correcting for the different sensitivities of different tissues. See the article on effective dose for this calculation. In the case of non-uniform radiation, or radiation given to only part of the body, using the local equivalent dose alone would overstate the biological risks to the entire organism.

## History

The concept of equivalent dose was developed in the 1950s.[2] In its 1990 recommendations, the ICRP revised the definitions of some radiation protection quantities, and provided new names for the revised quantities.[3] Some regulators, notably the International Committee for Weights and Measures (CIPM) and the US Nuclear Regulatory Commission continue to use the old terminology of quality factors and dose equivalent, even though the underlying calculations have changed.[4]

## Units

The SI unit of measure for equivalent dose is the sievert, defined as one Joule per kg.[5] In the United States the roentgen equivalent man (rem), equal to 0.01 sievert, is still in common use, although regulatory and advisory bodies are encouraging transition to sieverts.[6]

## Related quantities

### Dose rate

To quantify the radiation risk of a particular environment or activity, the dose rate is routinely posted in hazardous areas. This represents the dose received per unit time spent in the area, usually measured in millisievert per hour or millirem per hour. Although equivalent dose rates may be used for this purpose, these figures are normally posted as absorbed dose rates for each radiation type.

### Dose equivalent

The similar-sounding dose equivalent can have slightly different definitions than equivalent dose, or it may refer to the same thing. Prior to 1990, the ICRP used the term "dose equivalent" to refer to the absorbed dose at a point multiplied by the quality factor at that point, where the quality factor was a function of linear energy transfer (LET). By contrast, the ICRP's current definition of "equivalent dose" represents an average over an organ or tissue, and radiation weighting factors independent of LET are used instead of quality factors. Starting with the publication of ICRP 60, the ICRP stopped using the exact words "dose equivalent" alone in that order, but four similar quantities were defined:[3]

• ambient dose equivalent
• directional dose equivalent
• personal dose equivalent
• equivalent dose

The International Committee for Weights and Measures (CIPM) and the US Nuclear Regulatory Commission continue to use the old terminology of quality factors and dose equivalent. The NRC quality factors are independent of linear energy transfer, though not always equal to the ICRP radiation weighting factors.[4] The NRC's definition of dose equivalent is "the product of the absorbed dose in tissue, quality factor, and all other necessary modifying factors at the location of interest." However, it is apparent from their definition of effective dose equivalent that "all other necessary modifying factors" excludes the tissue weighting factor.[7]

### Dosimetry reports

Cumulative equivalent dose due to external whole-body exposure is normally reported to nuclear energy workers in regular dosimetry reports. In the US, three different equivalent doses are typically reported:

## References

1. ^ a b "The 2007 Recommendations of the International Commission on Radiological Protection". Annals of the ICRP. ICRP publication 103 37 (2-4). 2007. ISBN 978-0-7020-3048-2. Retrieved 17 May 2012.
2. ^ Clarke, R.H.; and J. Valentin (2009). "The History of ICRP and the Evolution of its Policies". Annals of the ICRP. ICRP Publication 109 39 (1): pp. 75–110. doi:10.1016/j.icrp.2009.07.009. Retrieved 12 May 2012.
3. ^ a b "1990 Recommendations of the International Commission on Radiological Protection". Annals of the ICRP. ICRP publication 60 21 (1-3). 1991. ISBN 978-0-08-041144-6. Retrieved 17 May 2012.
4. ^ a b 10 CFR 20.1004. US Nuclear Regulatory Commission. 2009.
5. ^
6. ^ Nuclear Regulatory Commission. "NRC Regulations: §34.3 Definitions". United States Government. Retrieved 2007-03-14.
7. ^ 10 CFR 20.1003. US Nuclear Regulatory Commission. 2009.


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#### Rank-One Network: An Effective Framework for Image Restoration

##### Shangqi Gao, Xiahai Zhuang

The principal rank-one (RO) components of an image represent the self-similarity of the image, which is an important property for image restoration. However, the RO components of a corrupted image could be decimated by the procedure of image denoising. We suggest that the RO property should be utilized and the decimation should be avoided in image restoration. To achieve this, we propose a new framework comprised of two modules, i.e., the RO decomposition and RO reconstruction. The RO decomposition is developed to decompose a corrupted image into the RO components and residual. This is achieved by successively applying RO projections to the image or its residuals to extract the RO components. The RO projections, based on neural networks, extract the closest RO component of an image. The RO reconstruction is aimed to reconstruct the important information, respectively from the RO components and residual, as well as to restore the image from this reconstructed information. Experimental results on four tasks, i.e., noise-free image super-resolution (SR), realistic image SR, gray-scale image denoising, and color image denoising, show that the method is effective and efficient for image restoration, and it delivers superior performance for realistic image SR and color image denoising.

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# HVO loses two valued scientists, but gains two good friends

Release Date:

This week, HVO bade farewell to Marie Edmonds and Richard "Ricky" Herd, who have been working at the observatory since February 2004. Both came to HVO from Montserrat Volcano Observatory, in the Caribbean, where they studied the ongoing eruption of Soufriere Hills Volcano.

Our friends, Marie Edmonds and Ricky Herd.

(Public domain.)

Marie Edmonds is an expert in volcanic gases and the geology of volcanic deposits. Her work on Soufriere Hills Volcano was featured prominently in the IMAX movie "Forces of Nature." This research was of such high caliber that Marie was offered a prestigious Mendenhall Postdoctoral Fellowship (not normally granted to non-US citizens) to work at HVO.

Over the past two years, Marie applied her expertise in Open-Path Fourier Transform Infrared Spectroscopy (OP-FTIR) to the development of novel ways to monitor gas emissions from Kīlauea. OP-FTIR does not require direct sampling and can measure a variety of gas compositions. Correlating the gas emissions with other data, like deformation, seismicity, and eruptive behavior, could lead to a new understanding of why eruptions occur, and how they might be predicted.

Marie's research has led to a number of new insights into volcano processes and hazards. At the ocean entry, the plume generated by lava-seawater interaction contains a significant amount of acid gas. During large ocean entries, like those that occurred during the 1919 and 1950 Mauna Loa eruptions, Marie's work suggests that the plume would have a major environmental impact on humans, animals, vegetation, and marine life.

Marie also measured gases from Puu Oo with OP-FTIR, and has found that different types of volcanic behavior are driven by different modes of degassing. This knowledge will enable HVO to more accurately and rapidly assess eruptive conditions, and will be useful for hazards assessment and mitigation.

Ricky Herd is one of the rare individuals who can do almost anything in volcanology. He spent seven years monitoring and studying almost every aspect of the eruption of Soufriere Hills Volcano in Montserrat, and served as Scientist-in-Charge of the observatory.

In Hawaii, Ricky worked for HVO through the Center for the Study of Active Volcanoes at the University of Hawaii at Hilo. He contributed his tremendous skills to helping many groups at HVO, conducting field work, building equipment, and writing software. His responsibilities included teaching classes to undergraduate students and volcanologists from developing countries, helping to train the current and next generation of volcano scientists.

Ricky played a large part in the building of two remote scanners that will soon be providing near-real-time gas measurements from Puu Oo. Thanks to his efforts, HVO is now able to record gas data continuously during daylight hours. This data will be important to understanding how the volcano is behaving, and whether or not hazardous activity is imminent.

In addition, Ricky helped with the construction of camera systems for monitoring volcanoes, including one that was sent to Mount St. Helens. Ricky's innovative way of making topographic maps from photos taken during helicopter overflights will allow HVO to more closely track activity at Puu Oo, something which had not previously been feasible. These contributions will help HVO in its mission to monitor Hawaii's volcanoes and provide timely warnings of hazardous activity.

During their off-duty hours, Marie and Ricky thoroughly enjoyed exploring the islands. They could often be found whale watching, diving and snorkeling (especially with manta rays, dolphins, and sharks!), and looking for Hawaii's native birds. In the Saddle area and on the Hakalau Forest Reserve, they repeatedly spotted and photographed such rare birds as the palila and akiapolaau.

We will miss Marie and Ricky's innovation and enthusiasm. They introduced many new ideas and methods to the study of Hawaiian volcanoes that will be the focus of additional work for years to come. While we are losing two scientists, we know we have gained two good friends. Aloha and mahalo, Marie and Ricky! We wish you continued success, and many return visits.

————————————————————————————————————————————————————————————————

### Volcano Activity Update

This past week, activity levels at the summit of Kīlauea Volcano have remained at background levels. The number of earthquakes located in the summit area is low (usually less than 10 per day that are large enough to locate). Widening of the summit caldera, indicating inflation, appears to have resumed after pausing earlier in April.
Eruptive activity at Puu Oo continues. On clear nights, glow is visible from several vents within the crater. Lava continues to flow through the PKK lava tube from its source on the flank of Puu Oo to the ocean, with frequent surface flows breaking out of the tube at the 2,300-2,200-ft elevation. The most persistent of these breakouts has spawned the "Campout flow," which has advanced to the 1,600-ft elevation. In the last week, no active flows were reported on the coastal plain.

Lava is still entering the ocean at East Laeapuki, in Hawaii Volcanoes National Park. On the evening of June 24, a breakout began 50 m (165 ft) inland of the sea cliff, and, within a minute, had poured over the sea cliff onto the bench below. Much of the bench was coated with new lava by the next morning. The flow had crusted over by the 27th. The lava bench continues to grow following the major collapse of November 28 and is now approximately 1,000 m (3,300 ft) long by 315 m (1,000 ft) wide, with a total surface area of 20 ha (50 acres).

Access to the sea cliff near the ocean entry is closed, due to significant hazards. The National Park has reopened the surrounding area, however. If you visit the eruption site, check with the rangers for current updates, and remember to carry lots of water when venturing out onto the flow field.

There was one earthquake beneath Hawaii Island reported felt within the past week. A magnitude-2.9 earthquake occurred at 7:17 p.m. H.s.t. on Thursday, June 22, and was located 5 km (3 miles) northwest of Kīlauea summit at a depth of 7 km (4 miles).

Mauna Loa is not erupting. During the past week, earthquake activity remained low beneath the volcano's summit (one earthquake was located). Extension of distances between locations spanning the summit, indicating inflation, continues at slow rates.


text:
pdfTeX error (font expansion): auto expansion is only possible with scalable fonts even with \usepackage[T1]{fontenc}

According to this question: On pdfTeX error (font expansion): auto expansion is only possible with scalable fonts, microtype package, to get rid of the error, a scalable font must be loaded.

Package lmodern no longer seems available in MikTeX; all the "lm-something" package my repository offers are shown below:

Given that I install cm-super font family and add \usepackage[T1]{fontenc} to my document. But the error is still there.

MWE (excerpt from overleaf user Craig's CV sample):

\documentclass[12pt,letterpaper]{moderncv}        % possible options include font size ('10pt', '11pt' and '12pt'), paper size ('a4paper', 'letterpaper', 'a5paper', 'legalpaper', 'executivepaper' and 'landscape') and font family ('sans' and 'roman')

\usepackage[T1]{fontenc}
%\usepackage{lmodern}

% modern themes
\moderncvstyle{banking}                            % style options are 'casual' (default), 'classic', 'oldstyle' and 'banking'
\moderncvcolor{blue}                                % color options 'blue' (default), 'orange', 'green', 'red', 'purple', 'grey' and 'black'
%\renewcommand{\familydefault}{\sfdefault}         % to set the default font; use '\sfdefault' for the default sans serif font, '\rmdefault' for the default roman one, or any tex font name
%\nopagenumbers{}                                  % uncomment to suppress automatic page numbering for CVs longer than one page

% adjust the page margins
\usepackage{geometry}

\usepackage{import}

% personal data
\name{My}{Name}
\title{Curriculum Vitae}                               % optional, remove / comment the line if not wanted
\address{my address, line 1, line 2, line 3, postcode}{}{}% optional, remove / comment the line if not wanted; the "postcode city" and and "country" arguments can be omitted or provided empty

%----------------------------------------------------------------------------------
%            content
%----------------------------------------------------------------------------------
\begin{document}
%\makecvtitle

Undergraduate electrical and electronic engineer completing the final year of a master's degree.

\end{document}

What do I do to make the error go away? Thanks. Your help is appreciated.

Update: I followed the step Ulrike Fischer suggested in How do I invoke cm-super?. Now it seems cm-super is not correctly installed (I see a .pk rather than a .pfb in the log) even though I do have it in MikTek Package Manager

I have refreshed FNDB and updated formats in MikTek Options (Admin) after installing cm-super.

Googling leads me to this , but I don't know how to follow the advice. Could someone please tell me how to execute M.A. solution "updating pdftex.map by running initexmf --mkmaps" in Windows MikTek 2.9? And what else have I missed?

• I get no error when I run your document in texlive2016 – David Carlisle May 17 '16 at 18:17
• @DavidCarlisle I am willing to give up on MikTek and install TexLive at this point but ctan.org is down. Ctan mirrors are still running, but the search facility of all mirrors I have tried is based on the main ctan.org and is down. I have no way to find a usable download address of TexLive now. I will try again and see if ctan.org gets back online. Thanks for your comment. – Alex May 17 '16 at 20:11
• I didn't particularly mean you should install Tl (the results in miktex should be the same) but just mentioned which version i had used, for completeness. (ctan is planned downtime, it'll be back tomorrow morning) – David Carlisle May 17 '16 at 20:12

2 Answers

Well, I'm not sure but I think package lmodern should be part of the basic installation of MiKTeX.

Please see the following image. I called the MiKTeX Package manager and filtered for lm (Latin Modern). Then you can see if Latin Modern is installed, if you see an date in column Installed on. BTW: Do not forget to call package lmodern to activate Latin Modern in your TeX document ...

On the other side you should be able to install it later with the MiKTeX package manager, like you tried with cm-super.

Now to the last sentences of your question:

In windows you can open the terminal/console with:

Windows-key+R, type cmd, press enter and type the mentioned command into the new window: initexmf --mkmaps, then press enter ...

• (+1) Apologies for confusing things. People post too quick - I can't keep up! – cfr May 17 '16 at 22:20

I will answer this question of my own for documentation purpose: MikTeX by default doesn't come with any scalable fonts that pdfTeX is happy with - who knows exactly what makes pdfTeX happy except cm-super... When using MikTeX, if encounter auto expansion is only possible with scalable fonts error, install cm-super fonts family, execute initexmf --mkmaps command in console, and add \usepackage[T1]{fontenc} to TeX document.

• Are you sure it doesn't come with scalable fonts? Isn't it just that Computer Modern isn't available in scalable form? The standard postscript set are surely included, aren't they? I thought they were part of even the most basic LaTeX install. – cfr May 17 '16 at 22:21
• @cfr Rephrased. – Alex May 17 '16 at 22:32


text:
06-285 Tetsuya Hattori
Uniqueness of fixed point of a two-dimensional map obtained as a generalization of the renormalization group map associated to the self-avoiding paths on gaskets (52K, LaTeX 2e) Oct 9, 06
Abstract , Paper (src), View paper (auto. generated ps), Index of related papers

Abstract. Let $W(x,y) = a x^3 + b x^4 + f_5 x^5 + f_6 x^6 + (3 a x^2)^2 y + g_5 x^5 y + h_3 x^3 y^2 + h_4 x^4 y^2 + n_3 x^3 y^3 + a_{24} x^2 y^4 + a_{05} y^5 + a_{15} x y^5 + a_{06} y^6$, and $X=\frac{\partial W}{\partial x}$, $Y=\frac{\partial W}{\partial y}$, where the coefficients are non-negative constants, with $a>0$, such that $X^{2}(x,x^{2})-Y(x,x^{2})$ is a polynomial of $x$ with non-negative coefficients. Examples of the 2 dimensional map $\Phi:\ (x,y)\mapsto (X(x,y),Y(x,y))$ satisfying the conditions are the renormalization group (RG) map (modulo change of variables) for the restricted self-avoiding paths on the 3 and 4 dimensional pre-gaskets. We prove that there exists a unique fixed point $(x_f,y_f)$ of $\Phi$ in the invariant set $\{(x,y)\in R^2\mid x^2\ge y\}\setminus\{0\}$.

Files: 06-285.src( 06-285.comments , 06-285.keywords , rg2dim.tex )