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The purpose of this study was to analyze the use of computer-based test instruments (Computer-Based Tests = CBT) in measuring conceptual knowledge and character of student in General Physics course. This research is a type of descriptive research. The data are analyzed qualitatively and quantitatively. The analysed data consist of conceptual knowledge and character of student on test using a computer (CBT) and written exams (Paper-Based Testing = PBT) as comparisons including students' responses to the implementation of the test. The designed research instruments are test instrument based on CBT and PBT as well as a user response questionnaire. The results show that students' conceptual knowledge of physics using CBT is higher than PBT, although the scores are not significantly different. On the other hand, the results of the integration assessment test of student character values consist of indicators accuracy, perseverance, honesty and confidence show that the value of student character using CBT are also higher than PBT. In addition, the results of the manager's response analysis test show that the use of CBT provides several positive impacts compared to the use of PBT such as reducing paper use, reducing exam administration funds, easy in correcting questions, presenting test results easily and quickly, correcting questions accurately, and the last, the use of CBT is more objective and more friendly to the environment due to paperless. [ABSTRACT FROM AUTHOR]

In his 1921 paper Geometrie und Erfahrung, Einstein decribes the new epistemological status of geometry, divorced from any intuitive or a priori content. He calls that “axiomatics”, following Hilbert’s theoretical developments on axiomatic systems, which started with the stimulus given by a talk by Hermann Wiener in 1891 and progressed until the Foundations of geometry in 1899. Difficult questions arise: how is a theoretical system related to an intuitive empirical content? © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

This paper provides information, suggestions and resources for men, specifically cis-white men, to become allies, supporters and followers in the fight for equity and inclusion of women and underrepresented groups in physics in science, technology, engineering and mathematics fields in general and in society as a whole. [ABSTRACT FROM AUTHOR]

The paper considers issues related to the theoretical study of electromagnetic phenomena in a certain stationary coordinate system in various variations. The use of electromagnetic force, controlled, easy to handle, which is applicable in a wide variety of sites and devices. The main attention is directed to the analysis of a number of phenomena from the simplest electrical moments, and also in a more complex understanding are presented as the forces of the most powerful attraction, expressed as a very topical issue. It is these aspects that are considered in this study. Of course, the image of such a performance is precisely the electromagnetic design, the physics of which is built from the initial ideas about electromagnetism. The developed theoretical framework is also used to analyze a large number of phenomena, each of which requires its own analysis in all parameters. The description of the algorithm created at the moment is given in this paper. [ABSTRACT FROM AUTHOR]

The year 2020 was an extraordinary one for Armenia. The COVID-19 pandemic had a profound effect on diverse aspects of life. The country had not recovered from the aftermath when the war started in the fall of 2020, which further depressed the economy. And 2020 once again reveals the importance and role of science, in particular physics, in overcoming various problems and challenges, as well as in ensuring peace. This paper discusses the current situation of science in Armenia and the challenges that women face nowadays. [ABSTRACT FROM AUTHOR]

Two new applications of high performance computing based on the DSMC approach were presented in the Graeme Bird Plenary Lecture and are summarized in this paper. The paper first discusses the importance of bimodality in the velocity distribution function in characterizing unsteady shock oscillations as well as their role in understanding transitioning laminar shock-boundary layer flows. A second computational problem of the neutralization of a low-temperature ion beam plasma using the particle-in-cell approach is discussed and again the non-Maxwellian behavior of plasma electrons is shown to change the behavior of unsteady electron solitary waves. The paper looks both back and forwards in time and provides some assessment of the fundamental role of particle kinetic approaches in nonequilibrium gas dynamics. [ABSTRACT FROM AUTHOR]

When academic institutions in India closed abruptly in March 2020 due to the COVID-19 pandemic, formal education moved online. This transition had a very uneven impact given the significant digital divide between rural and urban India and the unequal distribution of digital resources in different institutions. Access to resources varied substantially by individual, based on socioeconomic factors as well as gender. Institutional support to the academic community during this critical period was largely inadequate, which has had serious consequences on the teaching of physics and other subjects that require laboratory instruction. Educational institutions also provide safe and enabling learning spaces for women students; reduced access to such facilities undermined the work-and study-related dynamics for women because of the scarcity of resources such as devices, data and time. This paper reports on efforts made towards understanding such challenges during the COVID-19 pandemic, and describes steps that were taken to address them. [ABSTRACT FROM AUTHOR]

The present form of quantum mechanics is based on the Copenhagen school of interpretation. Einstein did not belong to the Copenhagen school, because he did not believe in probabilistic interpretation of fundamental physical laws. This is the reason why we are still debating whether there is a more deterministic theory. One cause of this separation between Einstein and the Copenhagen school could have been that the Copenhagen physicists thoroughly ignored Einstein’s main concern: the principle of relativity. Paul A. M. Dirac was the first one to realize this problem. Indeed, from 1927 to 1963, Paul A. M. Dirac published at least four papers to study the problem of making the uncertainty relation consistent with Einstein’s Lorentz covariance. It is interesting to combine those papers by Dirac to make the uncertainty relation consistent with relativity. It is shown that the mathematics of two coupled oscillators enables us to carry out this job. We are then led to the question of whether the concept of localized probability distribution is consistent with Lorentz covariance. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

The history and the most important scientific results obtained during 46 years of RGD symposia are critically reported. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

Pump as turbine (PAT) is effectively used in the micro-hydro power plants as stand-alone or grid-connected and energy recovery applications. Generally, the efficiency of the PAT is lower than the conventional turbines as it is not explicitly designed to generate power. Therefore, in literature, various techniques are proposed for performance improvement of the PAT, such as rounding of blades and shroud, back cavity filling, etc., as minor modifications. In the same line, it is critical to understand the internal flow physics to reduce the losses and understand the potential improvement. In the present paper, Computational Fluid Dynamics is proposed to understand the effect of blade and shroud rounding on the performance of PAT with internal flow physics. The change in the flow physics after modifications by impeller rounding is presented essentially at Best Efficiency Point (BEP). It is noticed that the efficiency of PAT is increased from 68.5 % to 70. 2 %, mainly due to the reduction of flow separation at the impeller flow zone, validating the experimental results from the literature. However, as the pump is not designed for turbine applications and there are no guide blades, the hydraulic losses due to flow separations are significant even after blade and shroud rounding. There is further scope for performance improvement by redesigning the impeller. [ABSTRACT FROM AUTHOR]

This paper is a tribute to my colleague prof. RNDr. Ivan Baník, PhD, who died on July 2, 2017. It was shortly after we decided to work on this article. It took me quite long to continue and finish at least the small part of our planned work. His invention in preparing simple experiments was well known, and this was how we became not only colleagues but friends as well. Our common effort was to make students like physics. One way to increase the interest in physics is to strengthen the experimental component of physics teaching and, in particular, to promote simple experiments that student can also perform independently at home. The simple experiment helps to eliminate mechanical forms of studying, gives more tangible physical content and develops physical thinking. Provides a stimulus for own creative search of physical contexts. Physics is basically experimental, but the experiment is also a natural part of the learning process. [ABSTRACT FROM AUTHOR]

The Netherlands continues to see an increase in female physicists. Gender is still an important topic, but diversity is now considered to extend beyond gender alone. Increasingly, efforts to broaden diversity also target inclusiveness of less represented groups such as first-generation students and people of color. Among first-year bachelor students, the percentage of female students at some universities is approaching 30%. In this paper we present some of the initiatives to improve the diversity in the Dutch physics community, such as the NNV Diversity Prize for physics departments, a diversity brochure, guest lectures at secondary schools, and the Minerva Prize for young female or nonbinary physicists. [ABSTRACT FROM AUTHOR]

The paper presents a study of students' interest in science and the identification of interesting topics not covered in physics classes. 136 8th and 9th grade students from a particular primary school in Slovenia participated in the survey. The results show that primary school students find it interesting to learn about contemporary physics. Gender and interest in science influence students' choices of what topics they find interesting and their responses to lessons on the selected most interesting topic in physics. Specifically, of the seven proposed topics briefly presented to the students (radioactivity, liquid crystals, physics in medicine, astronomy, energy sources, technical devices, and hydrogels), radioactivity proved to be the most interesting. Most students would like to learn more about the findings of contemporary physics, while one in three students would like to take an elective. For female students, physics in medicine ranked first in interest, while for male students, radioactivity ranked first. Students found school lessons on radioactivity interesting. The results indicate that students want to learn about the content of contemporary physics and that such topics are more attractive to them than the content of regular physics classes, which is also shown in the evaluation of the most popular topic, radioactivity. The research indirectly appeals to teachers to include contemporary physics topics in physics classes. [ABSTRACT FROM AUTHOR]

This paper aims to develop a student worksheet with a discovery learning-STEM model on dynamic electric material to build on students' problem-solving skills in YAPPI Wonosari Vocational High school. The method used is R&D with a 4-D model that includes defining, designing, developing, and disseminating. The instruments used include validation sheets and tests—data in a physics worksheet to improve students' problem-solving skills. This study's data collection methods contain expert validation, observation, pre-test, and post-test—the data analysis using the sign test. The results showed that 1) the development of student worksheets with discovery learning-STEM on dynamic electric material was feasible in terms of the validation results. This can be seen from the results of validation that show the feasibility of physics worksheets for improving problem-solving skills is in the excellent category, and 2) the effectiveness of using physics worksheet with discovery learning-STEM based on data obtained from the pre-test and post-test results can improve problem-solving skills as a problem in the implementation class. Thus, student worksheet developed with discovery learning STEM is compatible with improving problem-solving skills. [ABSTRACT FROM AUTHOR]

Based on the famous work of K. Lynch [7] on image-ability of a cityscape, recently a city of physics analogy has been proposed by A.E. Tabor et al.[8] to enhance the cognitive coherence of physics as a subject. The idea of both Lynch and A. abor. et al. is being extended in this paper to image-ability of an undergraduate Solid State Physics course to bring forth cognitive coherence of the subject in a global manner. In this paper an image-ability map of the course is presented both in a pictorial and tabular format with recognition of sections of the syllabus as districts and sub districts. Further in each district and sub district, key concepts as land marks, variables involved as nodes, key physical equations as paths and limits on variables as edges or boundaries are identified through peer discussion among a group of teachers who are teaching this course for the last couple of years. This exercise has helped not only in mental mapping of the subject but focusing on hitherto isolated and advanced topics provided in the syllabus as leading to a very different mental recreational spots in the cityscape of undergraduate Solid State Physics. [ABSTRACT FROM AUTHOR]

After a brief review of the early development of sheet forming simulation, we discuss some of the more recent work. In particular, we consider how it has developed over the years since the NUMISHEET Conferences have been held. The aim here is to give a broad overview of the development of current capabilities in simulating sheet metal forming, not to explore any specific research topic. It is hoped that this short report will help set the stage for the more detailed lectures and papers to follow in this Conference. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

This paper deals with three classes of nonlinear Schrödinger equations (NLSE) having general polynomial nonlinearities. We find travelling wave solutions of soliton type (smooth solitons, peakons and cuspons), periodic ones (smooth, peakons and cuspons) and kinks. In the case of some special polynomials the solutions are expressed up to the inverse map by Gauss and Appell's hypergeometric functions, by some elliptic functions of Jacobi and Weierstrass types etc. In each case the above mentioned solutions of NLSE are obtained into integral form. [ABSTRACT FROM AUTHOR]

The first Department of Physics in Zambia was established at the University of Zambia (UNZA) in Lusaka in 1966. In the years that followed, there were many physics graduates from this institution, and all were men. In 2004, the university produced the first woman physics graduate in Zambia. Although it took 38 years to achieve this, in Zambia, there have since been many more women physics graduates. In addition, the Copperbelt University (CBU) in Kitwe has introduced programmes in physics, resulting in an increase in the number of physics graduates, including women. Some graduates have gone on to become teachers, lecturers, researchers, public servants, and workers in industry. Others have had challenges in finding job opportunities in their field and are either unemployed or working in other fields, such as agriculture and banking. Even with the abundance of opportunities and research funding targeted at women in science, not enough physicists have taken advantage of this. It seems that there is a gap between physicists and their opportunities because of limited networking among physicists; limited awareness of activities, documentation, and relevance to society; and the lack of representation by an established local society of physicists. In this paper, we explore both the opportunities and challenges that physicists face, especially women in physics, in their journey to build a career in this field. We also explore what can be done to alleviate the challenges and highlight the opportunities to build bridges for more women to participate in physics in Zambia. [ABSTRACT FROM AUTHOR]

LADY CATS (LADY Creators of Activities for Teaching Science) is an organization of science teachers. Our group includes a lot of female teachers, which is rather unusual in the field of physics. We would like to propose and exhibit beautiful and simple science experiments that can demonstrate the principles of physics to fascinate students’ interest. These experiments are easily made and low-cost. It is also aimed to catch female and humanities students’ eyes on physics from the view point of female teachers. Furthermore, we believe that these ideas help resolve gender problems and support non-specialist teachers in primary school. [ABSTRACT FROM AUTHOR]

This paper introduces a new method for measuring wideband instantaneous phase noise in GHz signals. The instantaneous phase noise is derived from the concatenated phase noise spectrum. It has been verified experimentally to at least 2.5 GHz. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

This paper presents an example of the application of a genetic algorithm to a 2-D design problem, which consists in the reconstruction of the function that describes the convective heat transfer coefficient, when the position of the moving interface of the phase change is well-known. In numerical calculations the Tikhonov regularization, the genetic algorithm and the alternating phase truncation method were used. The featured examples of calculations show a very good approximation of the exact solution and the stability of the procedure. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

At therapeutic intensities, the application of ultrasound is often accompanied by bubble activity. Bubbles concentrate (by orders of magnitude) acoustic energy and convert that acoustic energy into mechanical, thermal, chemical or frequency-shifted acoustic energy. Depending on the specific clinical context, bubble and cavitation activity may be welcome or unwelcome. Whether desirable or not, certain basic phenomena may be observed, and certain basic principles deduced which can guide researchers in their efforts either to avoid or to exploit cavitation. Towards that end this paper will introduce the fundamentals of bubble dynamics. A bestiary of bubble phenomena and related concepts (such as the Blake threshold, inertial cavitation, shape instabilities, rectified diffusion) will be discussed. The dependence of bubble dynamics on control parameters (acoustic frequency and pressure, pulse parameters) and material properties (shear viscosity, surface tension, temperature, elasticity) will be considered. Experimental techniques and diagnostics for bubble detection and monitoring will be briefly mentioned. Tools for modeling bubble dynamics and their effects will be introduced. Some consequences of bubbles and cavitation activity in vivo (both physical and biological) will be presented, drawing on the example of bubbles in high-intensity focused ultrasound (HIFU) applications. Finally, recommendations of techniques for either avoiding or enhancing (and maybe controlling) cavitation will be proffered. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Subramanian “Ram” Raman, a distinguished nuclear physicist and senior staff member of the Physics Division at Oak Ridge National Laboratory (ORNL), died April 8, 2003. In June 1966, Raman joined the staff at ORNL working in the Nuclear Data Project. This position provided him insights into important open questions in nuclear structure physics, and the power of “horizontal” compilations of properties across a broad range of nuclei. These insights would guide Raman’s research interests throughout his 36-year career at ORNL. As shown by his great variety of publications, Raman’s research career was marked by an intense interest in all areas of nuclear physics. He published papers on topics ranging from detailed nuclear structure to giant resonances, to the search for superheavy nuclei, to the scattering of heavy ions. His research resulted in over 200 published papers and over 3000 citations of his work. It is however, his nuclear data evaluations, both horizontal and vertical, that we most often remember. His most often cited papers deal with the evaluation and systematics of nuclear data, and he helped establish many of the “rules” and guidelines for assignment of nuclear level properties. An overview of Raman’s work at ORNL is presented. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

The purpose of this paper is to illustrate that direct simulation Monte Carlo methods can often be considered as rigorous mathematical tools for solving nonlinear kinetic equations numerically. First a convergence result for Bird’s DSMC method is recalled. Then some sketch of the history of stochastic models related to rarefied gas dynamics is given. The model introduced by Leontovich in 1935 provides the basis for a rigorous derivation of the Boltzmann equation from a stochastic particle system. The last part of the paper is concerned with some recent directions of study in the field of Monte Carlo methods for nonlinear kinetic equations. Models with general particle interactions and the corresponding limiting equations are discussed in some detail. In particular, these models cover rarefied granular gases (inelastic Boltzmann equation) and ideal quantum gases (Uehling-Uhlenbeck-Boltzmann equation). Problems related to the order of convergence, to the approximation of the steady state solution, and to variance reduction are briefly mentioned. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

In 1966 George Marx in his historical paper in Nature introduced the concept of interstellar ship driven by radiation pressure from terrestrial X-ray laser. He named the new concept “laser propulsion”. Marx arrived to conclusion that maximum efficiency of such ship will be achieved at β → 1.0. One year later, J.L. Redding published a different solution, leading to maximum efficiency at β = 0.414. As it will be shown in this paper, neither was right in their assessments of optimal conditions. Correct solution will be presented in order to solve the problem of relativistic mirror. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

A great deal has been published on ambient noise. Most of this has covered (a) omni directional levels, and (b) the vertical and horizontal directivity of shipping noise at low frequencies. There is some published material on the vertical directivity of wind generated noise at lower frequencies, but very little at higher frequencies. In order to study wind generated ambient noise at higher frequencies, work has recently started using a small planar array from QinetiQ Bincleaves. As well as measurements, a model called CANARY has been written to predict ambient noise vertical directivity and array responses to this noise. This paper contains some comparisons between CANARY predictions and (a) previous measured vertical directivity data at 4.5 kHz, (b) measured omni-directional data, and (c) initial analysis of the planar array measurements. The paper shows the nature of the ambient noise vertical structure at higher frequencies and that the CANARY predictions are in good agreement with the measurements. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

We have shown recently that ionic doping (with SOCl2, iodine, HNO3) of single wall carbon nanotubes (SWNT) buckypaper causes an increase of electrical conductivity (factor of 5 for SOCl2-doping). Optical absorption spectra of ionic-doped SWNT show a vanishing of the first peak of van Hove singularities for semiconducting tubes, and at the same time a significant increase of the absorbance in the infrared region. In contrast, molecules forming covalent bonds with SWNT affect the properties of buckypaper so that electrical conductivity decreases (factor of 9 for aniline-functionalization) and the absorbance in the infrared region of the optical absorption spectra is reduced, unlike what is observed for ionic doping. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

Two papers that were published a decade ago are reviewed. One of them is The fight against the second law of thermodynamics and the other is Szilard's demon revisited. This review focuses on the claim that thermodynamic quantities (e.g. the temperature) of a system can depend on the way they are measured. In turn, this can depend on the knowledge the observer has about the system. [ABSTRACT FROM AUTHOR]

The advantages of autoclaved aerated concrete (AAC) masonry in terms of thermal properties and affordability have already been widely discussed. Nowadays, we are able to achieve the required thermal resistance of facades without the need to apply an external thermal insulation composite system on the entire surface. Decreasing the heat transfer coefficient is usually associated with increasing the proportion of pores in the material. However, this in turn adversely affects the sound insulation properties of simple partitions. Therefore, in effort to achieve the specific acoustic requirements of simple masonry AAC walls, structures of unacceptable thickness in practice may be designed. In this paper we present a study focused on the analysis of the dependence of the heat transfer coefficient resp. thermal resistance of structures and airborne sound insulation of simple walls based on AAC. [ABSTRACT FROM AUTHOR]

The various roles that theoretical work plays in the evolution of physics are reviewed, and classified. The need for properly justified uncertainty estimates to accompany theoretical atomic and molecular data is discussed. A new set of guidelines is described for the conditions under which uncertainty estimates should be included in published work. [ABSTRACT FROM AUTHOR]

We clarify the original thought for the scheme in our recent paper (Phys. Rev. A, 77, 042317), for preparing arbitrary four-qubit decoherence-free states robust against collective decoherence. Our method needs two singlet states and a tunable partial exchanging device. [ABSTRACT FROM AUTHOR]

Computer-based assessment greatly helps the teacher's task in assessment, especially for objective tests. This study aimed to develop a computer-based test design (CBT) for physics class X using the Moodle platform version 3.6.4. This study uses research and development (R&D) methods that refer to the ADDIE development model (Analysis, Design, Development, Implementation, Evaluation). The product made displays computer-based tests using the Moodle media platform by presenting 5 types of objective tests with several different question packages. In addition, the test is complemented by a safe exam browser application, which is an exam isolation room. Media experts have validated this CBT product with an achievement percentage of 87.3% with excellent interpretation results. [ABSTRACT FROM AUTHOR]

The fundamental symmetries, charge conjugation (C), parity (P) and time reversal (T), play a significant role in the Standard Model (SM) of elementary particle physics. Of these, T symmetry and the combined CP symmetry are the least well understood, and they hold valuable clues for unraveling the secrets of nature. All subatomic particles are postulated to possess an intrinsic property known as a permanent electric dipole moment (EDM). The EDM of an atom is a combination of those of each constituent particle and also CP-violating interactions between the particles. Being many-particle systems, atoms and molecules are ideal candidates for probing a rich variety of both T- and CP-violating interactions. Paramagnetic atoms, which have a single valence electron in their outer shell, are sensitive to subtle signals associated with CP violations in the leptonic sector, i.e., the EDM of the electron. At present, we are developing a high-intensity laser-cooled Fr factory at RIKEN accelerator facility in an attempt to evaluate the EDM of Fr to an accuracy of 10-30 ecm. Laser cooling is important for achieving highly accurate EDM measurements, since it allows long interaction times using an optical lattice. The current status of the laser-cooled Fr EDM experiments is presented in this paper. [ABSTRACT FROM AUTHOR]

Fermilab E906/SeaQuest is an experiment aimed at studying the anti-quark distributions of nucleons and nuclei. The experiment uses a 120 GeV/c proton beam extracted from the Main Injector at Fermilab to collide with various solid and cryogenic targets to study a variety of physics topics ranging from light anti-quark flavor asymmetry in the nucleon sea to dark photons. The experiment takes advantage of the Drell-Yan process in order to probe specifically the high-x anti-quark distributions of the target nucleus. The acceptance of the spectrometer is tuned to explore the unprecedentedly high Bjorken-x region, thereby extending our knowledge of the anti-quark sea structure of nucleons and nuclei. Some of the physics goals from the Drell-Yan program at SeaQuest and the current status of some analyses are reported in this paper. [ABSTRACT FROM AUTHOR]

Superconductors are demonstrated to profoundly differ in arrangement yet elusive and mysterious. To understand the Josephson Effect, it is advisable to first acquire some notion about the origin of the superconductivity. Macroscopically, superconductivity manifests itself as a lack of resistance, so that the current flows with no obstacles. The practical applications of superconductivity are consistently improving each year. However, the real utilization of superconducting devices is constrained by the way that they should be cooled to low temperatures to move toward becoming superconducting. The revelation of high-Tc superconductors broadens the feasible application of superconductors. The Josephson Effect has enabled the advancement of unique electrical devices and systems including SQUIDs, quantum computers, analog to digital (A/D) converters, Josephson voltage standard, THz emitters and detectors, single flux quantum devices, etc. In this research paper, we studied the Superconducting materials, its characteristics and applications in physics. [ABSTRACT FROM AUTHOR]

Motivated by the recent interest growing in contact structures, this paper is devoted to even-dimensional counterpart of contact geometry, namely the locally conformal symplectic one. In physics, these structures come natural from endowing the phase-space with a 2-form that is non-degenerate but locally closed up to a multiplicative non-vanishing function. In view of this, we initially adopt the trivial line bundle situation and show that a given locally conformal simplectic over an even-dimensional manifold leads to a transitive Jacobi pair and conversely. Then, we introduce the geometric perspective on locally conformal symplectic structures in terms of a line bundle over an even-dimensional manifold, L → M endowed with a flat-connection, ∇ and an L-valued non-degenerate and closed 2-form, ω ∈ Ω (M; L). In this framework we also exhibit the connection between locally conformal symplectic structures and transitive Jacobi ones. [ABSTRACT FROM AUTHOR]

In this paper we study both, analytically and numerically, the spatio-temporal dynamics of a three interacting species mathematical model. The populations take the form of pollinators, a plant and herbivores; the model consists of three nonlinear reaction-diffusion-advection equations. In view of considering the full model, as a previous step we firstly analyze a mutualistic interaction (pollinator-plant), later on a predator-prey (plant-herbivore) interaction model is studied and finally, we consider the full model. In all cases, the purely temporal dynamics is given; meanwhile for the spatio-temporal dynamics, we use numerical simulations, corresponding to those parameter values for which we obtain interesting temporal dynamics. [ABSTRACT FROM AUTHOR]

After a very successful flurry of activities for a few decades to maximize the benefits of the formalism of Quantum Mechanics to connect the micro and macro universe, the applied physics community has successfully engineered sustained technological innovations for human social advancements. However, a significant segment of the theoretical physics community put their endeavors essentially in inventing realities that are esthetically pleasing to our human logics (epistemology) rather than staying focused on discovering the actual physical realities in nature driven by cosmic logics (ontology). The purpose of this paper is an attempt to formulate a Reality Epistemology that can leverage our enormous successes in science to re-focus our attention to discovering nature's realities by understanding the physical processes behind all natural interactions that collectively make the cosmic evolution progressing forward. We underscore the deviation from seeking reality to justify the key premise of the paper. We can “see” (measure) the universe only through the “eyes” of the various sensors (detectors). None of these sensors are completely known to us as yet. All sensors also have inherently limited capabilities to respond to input signals and limited capabilities to “report” only a part of all that it experiences. We are thus forced to develop our mathematical theories mixing our human logics and incomplete information and hence they are all provisional and incomplete since they are predicting only correctly measured but limited report by the detector. Thus, we should be careful not to jump into conclusion that we have captured all the necessary cosmic logics behind the interactions involved. We dissect the measurement process in a generic way along with well defined steps to apply Reality Epistemology, which will jointly allow us to develop a scientific methodology of iteratively refining our “successful” human logics that can evolve towards our goal of capturing the cosmic logics. The core content of this paper was first presented at the 2007 QTRF-4 conference at the Vaxjo University [1]. [ABSTRACT FROM AUTHOR]

As porous SiOCH is a widely used inter-metal dielectric for 65 nm nodes and below, the control of its elaboration process by in-line monitoring is necessary to guarantee successful integration of the material. In this paper, the sensitivities of several non-destructive metrology techniques towards the film elaboration process drifts are investigated. It appears that the two steps of the process should be monitored separately and that corona charge method is the most sensitive technique of the review for this application. [ABSTRACT FROM AUTHOR]

Temperature is the most critical parameter for controlling tissue ablation through HIFU. In this paper we introduce a new method to improve temperature estimation from ultrasound images taken during treatment. The most common way to monitor temperature change is through estimating the echo-strain which results from local changes in the speed of sound over a set of images. However, artifacts such as caused by the thermo-acoustic lens effect and from nonlinearities in the temperature coefficient of velocity, make this method unreliable even in images which are otherwise of very high quality, and unsuitable for use on its own on typical images, even after low pass filtering. In this paper we discuss improvements which result from including a model of the expected temperature distribution over space and time, derived from the heat equation. A Kalman filter, a well known stochastic estimator which allows the uncertainty in the model and echo strain measurements to be modelled explicitly, is used to predict temperature through determining the loci of contours of constant temperature. Suitable model parameters are derived through least squares fitting algorithm based on the temperature map. The results allow the extent of tissue damage caused by heating can be assessed readily. The model has been tested only on gel phantoms. Experimental results show that temperature contours can be estimated and tracked over time, offering potential for real time feedback to improve HIFU treatment. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

The paper discusses the utility and relevance of general purpose codes such as ABAQUS in forming simulations. The paper discusses some of the technologies embedded in ABAQUS and how they can be useful to simulating and solving industrial forming problems. The paper demonstrates this with three relevant examples pertaining to stamping, sheet-stretching and forming of medical devices made out of super-elastic materials. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Forming simulation technologies continues to develop at a rapid pace, to address formability, tolerance control, and product performance issues in an increasing range of processes, and in ever more detail. Springback prediction and compensation continue to evolve, with new concepts for improving the accuracy of the springback prediction for example by the incorporation of geometric drawbeads, and further refinement in compensation techniques. The paper highlights how the integration of simulation and geometry plays an ever more important role, in improving accuracy and reducing time. Other techniques which can help speed-up and improve simulation results for hydroforming, and tube bending are ‘classical’ and more recently ‘in-process’ optimization techniques. The paper will show the advantages on an industrial case, and the potential for the future. The paper will discuss how the PAM-STAMP 2G™ and PAM-TUBE 2G™ integrated solutions are successfully implemented to deliver a positive business impact, by providing virtual product quality assessment, tolerance control, and springback compensation. The paper will also discuss how new forming processes such as hot forming, superplastic forming, and tube hydroforming, can be accurately modeled using the new modules. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

In forging process, formability is limited by ductile fracture. In many cases forgeability is determined by the occurrence of ductile fracture and therefore limitations are set by the appearance of surface or internal cracks within regions that are highly strained due to extensive material flow. In this paper, the continuum damage mechanics framework for ductile materials developed by Lemaitre has been utilized numerically. A constitutive elastic-plastic-damage model has been implemented inside the finite element code ABAQUS. In forming process, crack closure effects have a strong influence on damage evolution. Therefore, it is necessary to split the tensile and compression stresses in damage evolution and deal with them separately. A modified version of Lemaitre model has been implemented and utilized through the study. The prediction of the surface cracks in forging is analyzed numerically. The results could correctly predict the location of surface cracks in the forging process. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Advances in the processing power of modern computer hardware and the availability of sophisticated simulation software have fostered the use of virtual prototyping techniques in the automotive industry. However, many engineering problems require simulation and optimization computations so complex that it is imperative to utilize parallel computing to solve these problems in reasonable time. In this paper, FETI-INDEED — a parallelized simulation code for sheet metal forming — as well as algorithms for distributed optimizations are examined. Because it is anticipated that increasingly large problems will need to be solved in the future, particular focus is put on scalability aspects of these components. Experimental results are provided for optimizations which were performed on a 300 CPU Opteron cluster. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

In the series of papers by Ida, Oda and Park, the complete description of Hawking radiation to the brane localized Standard model fields from mini black holes in the low energy gravity scenarios are obtained. In this proceedings, we briefly review what we have learned in those papers. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

The current paper refers to one of the new non-conventional forming procedures for sheets metal, namely incremental forming. Problems occurring during calculation of stress, thinning and the forces in the process of incremental sheet metal forming have been analyzed in this paper. The paper presents a comparison study based on the simulation by the finite element method of incremental sheet metal forming and experimental researches referred on the same process. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Probability of Detection (POD) studies are typically conducted on EDM notches, “manufactured” crack specimens, or actual in-service crack specimens. The purpose of this paper is the education of the aerospace community in the subtle differences and benefits of using each specimen type. Data from previous POD studies are compared to data from teardown of a retired passenger aircraft, resulting in POD data from in-situ defects. Analysis of this data reveals similarities and differences between signals for four (4) types of specimens and four (4) nondestructive inspection (NDI) methods. Additionally, the paper provides an awareness of the assumptions used in each type of POD study, and potential consequences of violating such assumptions. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

This short paper is a reply to Andrei Khrennikov’s challenge to give a concrete quantum-mechanical example where the Bayesian and frequentist approaches to probability lead to different predictions. The paper first reviews the difference between the Bayesian and frequentist approaches to hypothesis testing and then presents a simple example in quantum tomography for which Bayesian and frequentist predictions differ. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

The purpose of this work is to show that using the hyperbolic network around L1, the diversity of transfer options to the Distant Retrograde Orbits (DROs) in the Sun-Earth Planar Circular Restricted Three Body Problem can be increased. In contrast to previous works, the current paper will concentrate on the range of smallest available DROs. The attractiveness of the transfer options to these orbits will be revealed by including the stable manifolds of the Horizontal Lyapunov Orbits (HLOs) as a part of the transfer path. It will become clear that for a large range of DROs, lower ΔV budgets and/or far lower travel times are achievable. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

The evolution of the methods used to find solutions of Einstein’s field equations during the last 100 years is described. Early papers used assumptions on the coordinate forms of the metrics. Since the 1950s more invariant methods have been deployed in most new papers. The uses to which the solutions found have been put are discussed, and it is shown that they have played an important role in the development of many aspects, both mathematical and physical, of general relativity. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]