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## Über dieses Buch

This book offers an introduction to piezoelectric shells and distributed sensing, energy harvesting and control applications. It familiarizes readers with a generic approach of piezoelectric shells and fundamental electromechanics of distributed piezoelectric sensors, energy harvesters and actuators applied to shell structures. The book is divided into two major parts, the first of which focuses on piezoelectric shell continua, while the second examines distributing sensing, energy harvesting and control of elastic continua, e.g., shells and plates.

The exploitation of new, advanced multifunctional smart structures and structronic systems has been one of the mainstream research and development activities over the years. In the search for innovative structronics technologies, piezoelectric materials have proved to be very versatile in both sensor and actuator applications. Consequently, the piezoelectric technology has been applied to a broad range of practical applications, from small-scale nano- and micro-sensors/actuators to large-scale airplane and space structures and systems.

The book provides practicing engineers and researchers with an introduction to advanced piezoelectric shell theories and distributed sensor/energy harvester/actuator technologies in the context of structural identification, energy harvesting and precision control. The book can also be used as a textbook for graduate students. This second edition contains substantial new materials, especially energy harvesting and experimental components, and has been updated and corrected for a new generation of readers.

## Inhaltsverzeichnis

### Chapter 1. Introduction

In this book, generic double-curvature piezoelectric shell theories are derived; generic distributed structural sensing, identification, energy harvesting and vibration control theories of a generic deep shell continuum are presented. Open and closed-loop dynamic system equations and state equations of piezoelectric structronic systems are formulated. Simple reduction procedures are proposed and applications to other common geometries and structures are demonstrated in case studies. The revised book not only corrected typos and minor mistakes, but also added new chapters on optimal control of parabolic shells and energy harvesting of shells, including both theoretical and experimental aspects. Furthermore, laboratory and experimental components are added to, almost, all chapters on distributed sensing, energy harvesting and control of shell and non-shell structures and structronic systems. Note that performances of piezoelectric sensors/harvesters/actuators are restricted by breakdown voltages, hysteresis effects, limited strain rates, etc. These material properties need to be further improved in order to enhance the sensor/actuator performance and efficiency. Also, laboratory experiments were carried out over time; different materials with various dielectric constants from different venders were used in various studies presented in newly added Chaps. 1012. Extreme care should be taken when repeating those studies. It should be pointed out that all piezoelectric shell theories and distributed sensing/control and energy harvesting theories are based on a symmetrical hexagonal piezoelectric structure—class C6v = 6 mm . Extension of these theories to more generic piezoelectric materials, such as a triclinic structure, would make them even more comprehensive and versatile. Besides, the temperature effect, e.g., the pyroelectricity and thermal induced stress/strains, is not considered in all studies; it should be considered when a working environment has significant temperature variations.
Hornsen (HS) Tzou

### Chapter 2. Piezoelectric Shell Vibrations

Active piezoelectric structures capable of self-adaptation (Tzou & Anderson, 1992) and high-precision manipulations (Tzou & Fukuda, 1992).
Hornsen (HS) Tzou

### Chapter 3. Common Piezoelectric Continua and Active Piezoelectric Structures

In this chapter, applications of the generic piezoelectric shell theories to a number of common piezoelectric continua were presented. A four-step reduction procedure was introduced and it was demonstrated in two geometries. The first case was a piezoelectric plate which includes 1) a thick plate and 2) a thin plate. The derived system equations of the thick piezoelectric plate were completely identical to published results (Tiersten, 1969). The second case was a piezoelectric shell of revolution which represents another class of shell continua e.g., piezoelectric spheres, cylinders, cones, etc., which were discussed in detail. Applications of the generic shell vibration theory to other piezoelectric continua can be further explored. Note that the theory was derived based on a symmetrical hexagonal piezoelectric structure—class $${\text{C}}_{6{\text{v}}} = 6\, {\text{mm}}$$.
Hornsen (HS) Tzou

### Chapter 4. Distributed Sensing and Control of Elastic Shells

Distributed sensing and control of a generic distributed parameter system (DPS) or a generic smart structronic shell system, i.e., a deep elastic shell laminated with distributed piezoelectric sensor and actuator layers, was proposed and corresponding generic theories derived. Based on the direct piezoelectric effect, the distributed sensor can be used to monitor shell oscillations; the converse effect enables the distributed actuators to manipulate structural behaviors and to suppress structural vibrations. Two generic sensor/actuator design principles, i.e., the segmentation technique and the shaping technique, were also presented.
Hornsen (HS) Tzou

### Chapter 5. Multi-layered Shell Actuators

In this chapter, a theoretical development of a multi-layered thin shell distributed actuator is presented. The distributed actuator layers can be made of electromechanical sensitive materials which respond to externally supplied voltages and generate local control forces for active distributed vibration controls. Based on the assumptions, dynamic equations for the generic multi-layered thin shell actuator (with distributed control layers) were developed using Kirchhoff-Love’s theory and Hamilton’s principle. The system equations are generic and can be simplified to apply to many other common geometries and structures, such as plates (e.g., circular or rectangular), other conventional shells (e.g., cylindrical shell, spheres), beams, etc. The common geometries can be defined by the fundamental form, Lamé parameters, radii of curvatures, etc. It should be noted that the deformations resulting from transverse shears and rotatory inertias were neglected in the derivations.
Hornsen (HS) Tzou

### Chapter 6. Boundary Control of Beams

Distributed control of a PVDF laminated cantilever beam was studied in this chapter. The laminated cantilever beam had a distributed piezoelectric sensor and a distributed actuator; both were surface bonded. Closed-loop feedback controls of the beam using the displacement and velocity signals were respectively evaluated and results compared. The results showed that the displacement feedback controls were insignificant and the velocity feedback controls were much more effective. In the velocity feedback control, the system damping increased to an ultimate value and then gradually dropped down as the feedback gain continuously increased. This was caused by the additional constraint imposed by the boundary control moment at the free-end. The free-end boundary condition was gradually changing to a sliding-roller boundary condition as proved by finite element analyses and laboratory experiments.
Hornsen (HS) Tzou

### Chapter 7. Distributed Control of Plates with Segmented Sensors and Actuators

In the development of active piezoelectric/elastic structures, it was noted that a fully (symmetrically) distributed piezoelectric sensor/actuator could lead to minimum, or zero, sensing/control effects for anti-symmetrical modes of structures, especially with symmetrical boundary conditions. One method of improving the performance is to segment the symmetrically distributed sensor/actuator layers into a number of collocated sub-segments. In this chapter, mathematical models and analytical solutions of a simply supported plate with a single-piece distributed sensor/actuator and four-piece quarterly segmented sensors/actuators were derived. Modal sensitivities and modal feedback factors for the two sensor/actuator configurations are defined, and modal displacement and velocity feedbacks are formulated.
Hornsen (HS) Tzou

### Chapter 8. Convolving Shell Sensors and Actuators Applied to Rings

In this chapter, generic distributed piezoelectric shell convolving sensors and actuators were proposed and detailed electromechanical behaviors (sensor and actuator electromechanics) were analyzed. It was observed that the sensor output is contributed by membrane strains and bending strains experienced in the sensor layer. Two sensor sensitivities: 1) a transverse modal sensitivity and 2) a membrane modal sensitivity can be defined accordingly. In general, the transverse modal sensitivity is defined for out-of-plane transverse natural modes and the membrane modal sensitivity for in-plane natural modes. Proper design of distributed sensor shape and convolution can provide modal filtering to prevent observation spillover in distributed structural control systems.
Hornsen (HS) Tzou

### Chapter 9. Sensing and Control of Cylindrical Shells

In this chapter, distributed sensors and actuators for cylindrical shells were designed and their spatially distributed sensing/control effects were analyzed. Mathematical model and analytical solutions suggest that the fully distributed shell sensor is sensitive only to all odd modes and insensitive to all even modes. This is due to signal cancellations of positive and negative signals in opposite strain regions. The diagonal stripe sensor is sensitive only to the m = n modes and insensitive to the m ≠ n modes. Three sensor sensitivities, i.e., transverse, in-plane longitudinal x and in-plane circumferential θ, were defined for each sensor and their normalized sensitivities evaluated. It was observed that the in-plane sensitivities are insensitive to thickness variations of elastic shells because the in-plane strains remain identical regardless of the thickness change. However, the transverse sensitivity increases as the shell becomes thicker due to an increase of bending strains. Furthermore, control effects of a fully distributed actuator and a diagonal strip actuator are evaluated.
Hornsen (HS) Tzou

### Chapter 10. Microscopic Actuations and Optimal Control of Parabolic Shells

Open parabolic cylindrical shells are important to radial signal collection, reflection and/or transmission applied to radar antennas, space reflectors, solar collectors, etc. The spatially distributed microscopic modal control effectiveness induced by piezoelectric actuators laminated on a simply-supported parabolic cylindrical shell panel was investigated in this study. Distinct distributed modal actuation behaviors of transverse vibrations of the shell were analyzed based on a newly-formulated mode shape function. The expression of modal control force induced by an actuator patch was derived. The spatially distributed microscopic actuation effectiveness induced by an infinitesimal actuator element was also derived to precisely illustrate the spatial distribution behavior.
Hornsen (HS) Tzou

### Chapter 11. Linear/Nonlinear Piezoelectric Shell Energy Harvesters

Energy harvesting based on distributed piezoelectric laminated structures has been proposed and extensively investigated for over a decade. The objective of this study is to develop a generic distributed piezoelectric shell energy harvester theory based on a generic linear/nonlinear double-curvature shell, which can be simplified to account for many linear/nonlinear shell and non-shell type distributed energy harvesters. Distributed electromechanical coupling mechanism of the energy harvester was discussed; voltage and power output across the external resistive load of the shell energy harvester were evaluated. Those equations were explicitly expressed in terms of design parameters and modes. Once the intrinsic Lamé parameters and the curvature radii of the selected host structure are specified, one can simplify the piezoelectric energy harvesting equations to account for common shell and non-shell harvester structures. To demonstrate the simplifications, the generic piezoelectric shell energy harvesting mechanism was applied to a cantilever beam, a circular ring and a conical shell in cases studies. Again, the generic piezoelectric energy harvesting formulations derived from a double-curvature shell can be applied to many shell, e.g., ring shells, cylindrical shell, conical shells, paraboloidal shells, etc., and non-shell, e.g., plates, beams, etc., structures using two Lamé parameters and two curvature radii of the specified structures. Besides, these shell and non-shell structures can be either linear or nonlinear with the von Karman geometric nonlinearity. With given boundary conditions and external loading forces, generated voltage and power across the resistive load in the closed-circuit condition can be estimated for the distributed piezoelectric laminated structure.
Hornsen (HS) Tzou

### Chapter 12. Tubular Shell Energy Harvester

This chapter involved energy harvesting of a simply supported tubular (circular) cylindrical shell laminated with piezoelectric patches. The distributed modal energy generations using different energy harvester patch sizes (i.e., (1 mm,3.6°) in Case 1, (10 mm,30°) in Case 2, and (20 mm,60°) in Case 3) at various mode numbers were evaluated in case studies. Analytical and simulation results suggest that the maximum magnitude of the spatially distributed modal energies changes at various modes in two cases, due to the patch size enlarged or the number of energy harvester patches in the circumferential direction decreased. It should be noted that the signal averaging effects on energy harvester patches become more significant when the patch size continuously increasing. Additionally, the bending energy components are much smaller than the circumferential membrane energy component, and they increase when mode number increases. Furthermore, the maximum magnitude of the (m, n)th modal energy, in general, increases when energy harvester’s thickness hp or shell’s thickness h increases, but decreases when the shell radius R increases. A tubular shell energy harvesting system was designed and tested in the StrucTronics and Control Laboratory at Zhejiang University. Experimental results suggest that there is an optimal external loading resistance leading to the maximal power output. Both analytical predictions and experimental data were compared favorably. These data evaluated in this study can be used as guidelines to design the optimum piezoelectric energy harvester in practical engineering applications.
Hornsen (HS) Tzou

### Chapter 13. Finite Element Formulation and Analyses

Conventional elastic structures are “passive” in nature, i.e., they do not possess any inherent self-sensation and action/reaction capabilities. Thus, development of new-generation active structures with integrated sensors, actuators, and control electronics, i.e., so called the structronic system, has received an increasing attention and interest in recent years (Tzou & Anderson, 1992). This chapter presents a finite element development and analysis of integrated distributed piezoelectric sensor/actuator structures—active distributed parameter systems (DPS’s) or structronic systems.
Hornsen (HS) Tzou

### Backmatter

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# The Challenge of Revising an Impure Theory

### Russell Greiner

A pure rule-based program will return a set of answers to each query; and will return the same answer set even if the rules are re-ordered. To work effectively, however, many real-world programs are impure'', ie, include the Prolog cut !'' and not(.) operators. The answers returned by such programs do depend on the rule ordering. There are also many reasoning systems that return only the first answer found for each query; these first answers, too, depend on the rule order, even in pure rule-based systems. A theory revision algorithm, seeking the revised rule-based system that works best in such impure contexts, should therefore consider modifying the order of the rules, in addition to adding and deleting rules and antecedents. Such revision algorithms apply a sequence of modifications, seeking a rule-base whose expected accuracy, over the distribution of queries, is optimal. This paper first shows that a polynomial number of training labeled queries (each a query coupled with its correct answer) is sufficient to provide the distribution information necessary to identify the optimal ordering. It then proves, however, that the task of determine which ordering is optimal, once given this information, is intractable even in trivial situations; eg, even if each query is an atomic literal, we are seeking only a perfect'' theory, and the knowledge base is propositional. We also prove that this task is not even approximable: Unless P=NP, no polynomial time algorithm can produce an ordering whose accuracy is within n^{\epsilon} of optimal, for some \epsilon > 0, where n is the number of rules. We also prove similar hardness, and non-approximatability, results for the related tasks of determining, in these impure contexts, (1) the optimal ordering of the antecedents; (2) the optimal set of rules to add or (3) to delete; and (4) the optimal priority values for a set of defaults.

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# Heat should not be usedA.)Near an area of painB.)On the arms or legsC.)Near jointsD.)On an area of decreased sensation

###### Question:

Heat should not be used A.)Near an area of pain
B.)On the arms or legs
C.)Near joints
D.)On an area of decreased sensation

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### Follow drako3xx and dominicmaiava on t. i.k. t.o. k Please and thank you : )

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### Solve all 4 please.

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Igeologist note is that the land alone at fault line moved 24.8 cm over the past 175 years on average how much did the land more each year...

### What is pemdas and gems ? pls asap : ) will give brainliest if right

What is pemdas and gems ? pls asap : ) will give brainliest if right...

### Analyzing Rome's Expansion Which of Rome's natural geographic features helped its political and economic

Analyzing Rome's Expansion Which of Rome's natural geographic features helped its political and economic growth? Choose four correct answers. its mountain surroundings its river access to the sea its construction of roads its location on a seacoast its inland location its fertile farmland Plz help...

### Write 2 sentences each in spanish using a variety of er and ir verbs

Write 2 sentences each in spanish using a variety of er and ir verbs...

### Part AHow might the research described in the article help address the food supply for a growing population?

Part A How might the research described in the article help address the food supply for a growing population?...

### Compare the wavelengths of an electron (mass = 9.11 × 10−31 kg) and a proton (mass = 1.67 × 10−27

Compare the wavelengths of an electron (mass = 9.11 × 10−31 kg) and a proton (mass = 1.67 × 10−27 kg), each having (a) a speed of 3.19 × 106 m/s and (b) a kinetic energy of 3.96 × 10−15 J. Enter your answers in scientific notation. (a) Electron wavelength = × 10 m Proton wavelength = × 1...

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How does the slogan late long and few represent a change in his position...

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### Who else is tired of sitting in a chair 24/7 in school also free points amd this is what i look like

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### An unloaded truck and trailer, with the driver aboard, weighs 30{,}00030,00030, comma, 000 pounds. When fully loaded, the truck

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### Iwas 6 years old and my sister was half my age, im 60 now how old is my sister now? : 3

Iwas 6 years old and my sister was half my age, im 60 now how old is my sister now? : 3...

### Find the value of 'r' in c = 2πr if c = 15. show your solution.

Find the value of "r" in c = 2πr if c = 15. show your solution....

### List the 3 parts of the cell theory and name the three scientists that developed thecell theory.

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### Describe the emotional states of Bob Wilson and Richard Feynman in the opening of theexcerpt. Cite textual evidence in your response, focusing on actions

Describe the emotional states of Bob Wilson and Richard Feynman in the opening of the excerpt. Cite textual evidence in your response, focusing on actions and dialogue that support your description....

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# Calibration and time fading characterization of a new optically stimulated luminescence film dosimeter

Marco Caprioli, Laurence Delombaerde, Marijke De Saint-Hubert, Luana de Freitas Nascimento, Robin De Roover, Katleen Himschoot, Brent van der Heyden, Dirk Vandenbourcke, Paul Leblans

Research outputpeer-review

## Abstract

Background
Optically stimulated luminescence (OSL) dosimeters produce a signal linear to the dose, which fades with time due to the spontaneous recombination of energetically unstable electron/hole traps. When used for radiotherapy (RT) applications, fading affects the signal-to-dose conversion and causes an error in the final dose measurement. Moreover, the signal fading depends to some extent on treatment-specific irradiation conditions such as irradiation times.
Purpose
In this work, a dose calibration function for a novel OSL film dosimeter was derived accounting for signal fading. The proposed calibration allows to perform dosimetry evaluation for different RT treatment regimes.
Methods

A novel BaFBr:Eu2+-based OSL film (Zeff, 6 MV = 4.7) was irradiated on a TrueBeam STx using a 6 MV beam with setup: 0° gantry angle, 90 cm SSD, 10 cm depth, 10 × 10 cm2 field. A total of 86 measurements were acquired for dose-rates ( D ̇ $\dot{D}$ ) of 600, 300, and 200 MU/min for irradiation times (tir) of 0.2, 1, 2, 4.5, 12, and 23 min and various readout times (tscan) between 4 and 1440 min from the start of the exposure (beam-on time). The OSL signal, S ( D ̇ , t i r , t s c a n ) $S(\dot{D},{t}_{ir},{t}_{scan})$ , was modeled via robust nonlinear regression, and two different power-law fading models were tested, respectively, independent (linear model) and dependent on the specific t i r ${t}_{ir}$ (delivery-dependent model).
Results
After 1 day from the exposure, the error on the dose measurement can be as high as 48% if a fading correction is not considered. The fading contribution was characterized by two accurate models with adjusted-R2 of 0.99. The difference between the two models is <4.75% for all t i r ${t}_{ir}$ and t s c a n ${t}_{scan}$ . For different beam-on times, 3, 10.5, and 20 min, the optimum t s c a n ${t}_{scan}$ was calculated in order to achieve a signal-to-dose conversion with a model-related error <1%. In the case of a 3 min irradiation, this condition is already met when the OSL-film is scanned immediately after the end of the irradiation. For an irradiation of 10.5 and 20 min, the minimum scanning time to achieve this model-related error increases, respectively, to 30 and 90 min. Under these conditions, the linear model can be used for the signal-to-dose conversion as an approximation of the delivery-dependent model. The signal-to-dose function, D(Mi,j, t s c a n $\ {t}_{scan}$ ), has a residual mean error of 0.016, which gives a residual dose uncertainty of 0.5 mGy in the region of steep signal fading (i.e., t s c a n ${t}_{scan}\$ = 4 min). The function of two variables is representable as a dose surface depending on the signal (Mi,j) measured for each i,j-pixel and the time of scan ( t s c a n ${t}_{scan}$ ).
Conclusions
The calibration of a novel OSL-film usable for dosimetry in different RT treatments was corrected for its signal fading with two different models. A linear calibration model independent from the treatment-specific irradiation condition results in a model-related error <1% if a proper scanning time is used for each irradiation length. This model is more practical than the delivery-dependent model because it does not need a pixel-to-pixel fading correction for different t i r ${t}_{ir}$ .
Original language English 16076 1-9 9 Medical Physics https://doi.org/10.1002/mp.16076 Published - 10 Nov 2022


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## Description

 Title: Algorithms for VLSI routing Author(s): Zhou, Dian Doctoral Committee Member(s): Preparata, Franco P. Department / Program: Electrical and Computer Engineering Discipline: Electrical and Computer Engineering Degree Granting Institution: University of Illinois at Urbana-Champaign Degree: Ph.D. Genre: Dissertation Subject(s): Engineering, Electronics and Electrical Computer Science Abstract: This thesis considers the problems arising from VLSI routing design. Algorithms are proposed for solving both global and local routing problems.For routing multiterminal nets in the gate array and sea-of-gates technologies, we present a global router which upper bounds the global density of the routing by 2$s\sp{\*}$, where $s\sp{\*}$ is the span of the nets. For standard cell technology, we present a global router which achieves the optimal horizontal density while upper bounding the vertical density by 2$s\sp{\*}$. The parallel implementations of the proposed global routing algorithms are presented.For the local routing problem, we first investigate the efficiency of the Manhattan routing model. We study in detail how the grid points are used in the Manhattan model and, consequently, establish a general lower bound on the channel width for routing two-terminal nets in a channel. All of the previous known results (lower bounds on the channel width) can be derived from our general lower bound. Furthermore, an asymptotically tight lower bound is obtained. We are also able to establish the lower bounds on the routing area for routings in L-, S-, T- and X-junctions in both the Manhattan and knock-knee models.For routing in an arbitrary rectilinear polygon, which is a generalization of many local routing problems, we present a sublinear time algorithm running in O(m log$\sp2$ m), where m is the number of edges in the boundary of the polygon. The presented algorithm produces the minimal routing area. For routing in the restricted wire-overlap model, we present an optimal algorithm which constructs a routing with minimum channel width. In the routing produced by the algorithm, the length of the wire overlap between any two nets is upper bounded by O(k), where k is the multiplicity of the nets. Issue Date: 1990 Type: Text Language: English URI: http://hdl.handle.net/2142/20933 Rights Information: Copyright 1990 Zhou, Dian Date Available in IDEALS: 2011-05-07 Identifier in Online Catalog: AAI9114483 OCLC Identifier: (UMI)AAI9114483


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Spin alignment measurements of the K*0(892) and phi (1020) vector mesons in heavy ion collisions at s(NN)**(1/2) = 200 GeV
Phys.Rev.C 77 (2008) 061902, 2008.
The collaboration

Abstract (data abstract)
We present the first spin alignment measurements for the $K^{*0}(892)$ and $\phi(1020)$ vector mesons produced at midrapidity with transverse momenta up to 5 GeV/$c$ at $\sqrt{s_{NN}}=200$ GeV at RHIC. The diagonal spin-density matrix elements with respect to the reaction plane in $Au+Au$ collisions are $\rho_{00}=0.32 \pm 0.04 (\mbox{stat}) \pm 0.09 (\mbox{sys})$ for the $K^{*0}$ ($0.8 < p_{T} < 5.0$ GeV/$c$) and $\rho_{00}=0.34 \pm 0.02 (\mbox{stat}) \pm 0.03 (\mbox{sys})$ for the $\phi$ ($0.4 < p_{T} < 5.0$ GeV/$c$) and are constant with transverse momentum and collision centrality. The data are consistent with the unpolarized expectation of 1/3 and thus no evidence is found for the transfer of the orbital angular momentum of the colliding system to the vector-meson spins. Spin alignments for $K^{*0}$ and $\phi$ in $Au+Au$ collisions were also measured with respect to the particle’s production plane. The $\phi$ result, $\rho_{00}=0.41 \pm 0.02 (\mbox{stat}) \pm 0.04 (\mbox{sys})$, is consistent with that in $p+p$ collisions, $\rho_{00}=0.39 \pm 0.03 (\mbox{stat}) \pm 0.06 (\mbox{sys})$, also measured in this work. The measurements thus constrain the possible size of polarization phenomena in the production dynamics of vector mesons.


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All Questions

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text:
# pst-eucl bold labels and arc sizes

I got a couple of questions about pst-eucl. How can I make a point label bold? I've tried the following permutations

\pstGeonode[PointName=\textbf{A}](1,1){A}(-1,-1){B}
\pstGeonode[PointName={\bf A}](1,1){A}(-1,-1){B}
\pstGeonode[PointName=\bf{A}](1,1){A}(-1,-1){B}

but I can't make it work.

Also, how can I control the radius of the angles arcs? So if i have overlapping arcs they don't intersect.

-
Can you add a minimal (non) working example to play with? –  egreg Feb 3 '13 at 22:42
I've updated my solution to be a better approach. –  A.Ellett Feb 3 '13 at 23:36

I've frequently had this problem. There seems to be something in the way that key PointName is implemented in pst-eucl that's getting in the way.

The way \pstGeonode is setting the node names is through an artifact of how \psnode works---which is expecting something expandable in \edef to create string for the internal name for the node. When you're formatting the text with something like \textbf, you're creating something that won't work as a node name.

But the good news is that there is a reasonable work-around:

    \pstGeonode[PointName=none](1,-2){C}
\rput([nodesep=1em,angle=-90]C){\textbf{C}}

So, the MWE is now:

\documentclass{article}
\usepackage{pst-eucl}
\begin{document}

\begin{pspicture}[showgrid=false](-4,-4)(4,4)

\pstGeonode[PointName=none](1,1){A}
\uput[135](A){\texttt{A}}

\pstGeonode[PointName=none](1,-1){B}
\uput[-45](B){{\scriptsize B}}

\pstGeonode[PointName=none](1,-2){C}
\uput[-90](C){\textbf{C}}

\end{pspicture}

\end{document}

Output:

There are actually two different syntaxes which work here:

You can use \rput and pass key-values:

\rput([nodesep=1em,angle=135]A){\textbf{A})

But pstricks provides a better vehicle for applying labels to nodes:

\uput*{labelsep}[refangle]{rotation}(x,y){stuff}

where the labelsep and rotation arguments may be omitted. In place of the coordinates (x,y) you may substitute the node name (A).

-
Thank you so much :D –  JustDanyul Feb 4 '13 at 2:05


text:
# RdTextFilter: Select text in an Rd file.

### Description

This function blanks out all non-text in an Rd file, for spell checking or other uses.

### Usage

 ```1 2 3``` ```RdTextFilter(ifile, encoding = "unknown", keepSpacing = TRUE, drop = character(), keep = character(), macros = file.path(R.home("share"), "Rd", "macros", "system.Rd")) ```

### Arguments

 `ifile` An input file specified as a filename or connection, or an `"Rd"` object from `parse_Rd`. `encoding` An encoding name to pass to `parse_Rd`. `keepSpacing` Whether to try to leave the text in the same lines and columns as in the original file. `drop` Additional sections of the Rd to drop. `keep` Sections of the Rd file to keep. `macros` Macro definitions to assume when parsing. See `parse_Rd`.

### Details

This function parses the Rd file, then walks through it, element by element. Items with tag `"TEXT"` are kept in the same position as they appeared in the original file, while other parts of the file are replaced with blanks, so a spell checker such as `aspell` can check only the text and report the position in the original file. (If `keepSpacing` is `FALSE`, blank filling will not occur, and text will not be output in its original location.)

By default, the tags `\S3method`, `\S4method`, `\command`, `\docType`, `\email`, `\encoding`, `\file`, `\keyword`, `\link`, `\linkS4class`, `\method`, `\pkg`, and `\var` are skipped. Additional tags can be skipped by listing them in the `drop` argument; listing tags in the `keep` argument will stop them from being skipped. It is also possible to `keep` any of the `c("RCODE", "COMMENT", "VERB")` tags, which correspond to R-like code, comments, and verbatim text respectively, or to drop `"TEXT"`.

### Value

A character vector which if written to a file, one element per line, would duplicate the text elements of the original Rd file.

### Note

The filter attempts to merge text elements into single words when markup in the Rd file is used to highlight just the start of a word.

### Author(s)

Duncan Murdoch

`aspell`, for which this is an acceptable `filter`.


text:
# Chemical equilibrium

## Exercise 16

Give the definition of $K_s$ for the saturated solution resulting from the equilibrium (don't write (aq) ): $Ag_3PO_4(s)$ $3Ag^+(aq)$ $+$ $PO_4^{3-}(aq)$ $Ca_3(PO_4)_2(s)$ $3Ca^{2+}(aq)$ $+$ $2PO_4^{3-}(aq)$ $CaF_2(s)$ $Ca^{2+}(aq)$ $+$ $2F^-(aq)$ $Al_2S_3(s)$ $2Al^{3+}(aq)$ $+$ $3S^{2-}(aq)$