WorldWideScience

Sample records for physicists quietly chattering

  1. Physicists

    CERN Document Server

    Snow, CP

    2010-01-01

    C P Snow's sketches of famous physicists and explanation of how atomic weapons were developed gives an overview of science often lacking. This study provides us with hope for the future as well as anecdotes from history.

  2. Chatter and machine tools

    CERN Document Server

    Stone, Brian

    2014-01-01

    Focussing on occurrences of unstable vibrations, or Chatter, in machine tools, this book gives important insights into how to eliminate chatter with associated improvements in product quality, surface finish and tool wear. Covering a wide range of machining processes, including turning, drilling, milling and grinding, the author uses his research expertise and practical knowledge of vibration problems to provide solutions supported by experimental evidence of their effectiveness. In addition, this book contains links to supplementary animation programs that help readers to visualise the ideas detailed in the text. Advancing knowledge in chatter avoidance and suggesting areas for new innovations, Chatter and Machine Tools serves as a handbook for those desiring to achieve significant reductions in noise, longer tool and grinding wheel life and improved product finish.

  3. Analysis of Chatter Stability in Facing

    Science.gov (United States)

    Kebdani, S.; Sahli, A.; Rahmani, O.; Boutchicha, D.; Belarbi, A.

    This study attempts to develop a chatter model for predicting chatter stability conditions in hard turning. A linear model is developed by introducing non-uniform load distribution on a tool tip to account for the flank wear effect. Stability analysis based on the root locus method and the harmonic balance method is conducted to determine a critical stability parameter. To validate the model, a series of experiment is carried out to determine the stability limits as well as certain characteristic parameters for facing and straight turning. Chatter in hard turning has the feature that the critical stability limits increase very rapidly when the cutting speed is higher than 13 rev sec-1 for all feed directions. The main contributions of the study are threefold. First, chatter-free cutting conditions are predicted and can be used as a guideline for designing tools and machines. Second, the characteristics of chatter in hard turning, which is observed for the first time, helps to broaden our physical understanding of the interactions between the tool and the workpiece in hard turning. Third, experimental stability limits for different flank wear can contribute to lead more reasonable ways to consider the flank wear effect in chatter models of hard turning. Based on these contributions, the proposed linear chatter model will support to improve the productivity in many manufacturing processes. In addition, the chatter experimental data will be useful to develop other chatter models in hard turning.

  4. Telecom Modeling with ChatterBell.

    Energy Technology Data Exchange (ETDEWEB)

    Jrad, Ahmad M.; Kelic, Andjelka

    2017-12-01

    This document provides a description and user manual for the ChatterBell voice telecom modeling and simulation capability. The intended audience consists of network planners and practitioners who wish to use the tool to model a particular voice network and analyze its behavior under varying assumptions and possible failure conditions. ChatterBell is built on top of the N-SMART voice simulation and visualization suite that was developed through collaboration between Sandia National Laboratories and Bell Laboratories of Lucent Technologies. The new and improved modeling and simulation tool has been modified and modernized to incorporate the latest development in the telecom world including the widespread use of VoIP technology. In addition, ChatterBell provides new commands and modeling capabilities that were not available in the N-SMART application.

  5. Physicists' boycott

    CERN Document Server

    Charap, John M

    1980-01-01

    In CERN, scientists had taken action to boycott cooperation with their Soviet counterparts. This is in protest at the detention of the distinguished Russian particle accelerator physicist, Dr Yuri Orlov; 8,000 scientists from more than 40 countires have signed similar pledges

  6. Quiet areas

    DEFF Research Database (Denmark)

    Petersen, Rikke Munck

    2016-01-01

    This paper argues that drone filming can substantiate our understanding of multisensorial experiences of quiet areas and urban landscapes. Contrary to the distanced gaze often associated with the drone, this paper discusses drone filming as an intimate performativity apparatus that can affect...... perception as a result of its interrelationships between motion, gaze, and sound. This paper uses four films, one of which is a drone flyover, to launch a discussion concerning a smooth and alluring gaze, a sliding gaze that penetrates landscapes, and site appearance. Films hold the capacity to project both...... and transcendence can facilitate a deeper understanding of intimate sensations, substantiating their role in the future design and planning of urban landscapes. Hence, it addresses the ethics of an intimacy perspective (of drone filming) in the qualification of quiet areas....

  7. Experimental evaluation of earthquake induced relay chattering

    International Nuclear Information System (INIS)

    Bandyopadhyay, K.; Hofmayer, C.; Shteyngart, S.

    1990-01-01

    An experimental evaluation of relay performance under vibratory environments is discussed in this paper. Single frequency excitation was used for most tests. Limited tests were performed with random multifrequency inputs. The capacity of each relay was established based on a two-millisecond chatter criterion. The experimental techniques are described and the effects of parameters in controlling the relay capacity levels are illustrated with test data. A wide variation of the capacity levels was observed due to the influence of parameters related to the design of the relay and nature of the input motion. 3 refs., 15 figs

  8. Machining Chatter Analysis for High Speed Milling Operations

    Science.gov (United States)

    Sekar, M.; Kantharaj, I.; Amit Siddhappa, Savale

    2017-10-01

    Chatter in high speed milling is characterized by time delay differential equations (DDE). Since closed form solution exists only for simple cases, the governing non-linear DDEs of chatter problems are solved by various numerical methods. Custom codes to solve DDEs are tedious to build, implement and not error free and robust. On the other hand, software packages provide solution to DDEs, however they are not straight forward to implement. In this paper an easy way to solve DDE of chatter in milling is proposed and implemented with MATLAB. Time domain solution permits the study and model of non-linear effects of chatter vibration with ease. Time domain results are presented for various stable and unstable conditions of cut and compared with stability lobe diagrams.

  9. Correlation analysis of motor current and chatter vibration in grinding using complex continuous wavelet coherence

    International Nuclear Information System (INIS)

    Liu, Yao; Wang, Xiufeng; Lin, Jing; Zhao, Wei

    2016-01-01

    Motor current is an emerging and popular signal which can be used to detect machining chatter with its multiple advantages. To achieve accurate and reliable chatter detection using motor current, it is important to make clear the quantitative relationship between motor current and chatter vibration, which has not yet been studied clearly. In this study, complex continuous wavelet coherence, including cross wavelet transform and wavelet coherence, is applied to the correlation analysis of motor current and chatter vibration in grinding. Experimental results show that complex continuous wavelet coherence performs very well in demonstrating and quantifying the intense correlation between these two signals in frequency, amplitude and phase. When chatter occurs, clear correlations in frequency and amplitude in the chatter frequency band appear and the phase difference of current signal to vibration signal turns from random to stable. The phase lead of the most correlated chatter frequency is the largest. With the further development of chatter, the correlation grows up in intensity and expands to higher order chatter frequency band. The analyzing results confirm that there is a consistent correlation between motor current and vibration signals in the grinding chatter process. However, to achieve accurate and reliable chatter detection using motor current, the frequency response bandwidth of current loop of the feed drive system must be wide enough to response chatter effectively. (paper)

  10. Does Online Chatter Really Matter? Dynamics of User-Generated Content and Stock Performance

    NARCIS (Netherlands)

    S. Tirunillai (Seshadri); G.J. Tellis (Gerard)

    2011-01-01

    textabstractUser-Generated Content in online platforms or chatter for short provides a valuable source of consumer feedback on market performance of firms. This study examines whether chatter can predict stock market performance, which metric of chatter has the strongest relationship, and what the

  11. Sliding Control with Chattering Elimination for Hydraulic Drives

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.

    2012-01-01

    This paper presents the development of a sliding mode control scheme with chattering elimination, generally applicable for position tracking control of electro-hydraulic valve-cylinder drives. The proposed control scheme requires only common data sheet information, no knowledge on load characteri......This paper presents the development of a sliding mode control scheme with chattering elimination, generally applicable for position tracking control of electro-hydraulic valve-cylinder drives. The proposed control scheme requires only common data sheet information, no knowledge on load...... controller is developed for the control derivative based on a reduced order model. Simulation results demonstrate strong robustness when subjected to parameter perturbations and that chattering is eliminated....

  12. Analytical Prediction of Three Dimensional Chatter Stability in Milling

    Science.gov (United States)

    Altintas, Yusuf

    The chip regeneration mechanism during chatter is influenced by vibrations in three directions when milling cutters with ball end, bull nose, or inclined cutting edges are used. A three dimensional chatter stability is modeled analytically in this article. The dynamic milling system is formulated as a function of cutter geometry, the frequency response of the machine tool structure at the cutting zone in three Cartesian directions, cutter engagement conditions and material property. The dynamic milling system with nonlinearities and periodic delayed differential equations is reduced to a three dimensional linear stability problem by approximations based on the physics of milling. The chatter stability lobes are predicted in the frequency domain using the proposed analytical solution, and verified experimentally in milling a Titanium alloy with a face milling cutter having circular inserts.

  13. The Microphone Feedback Analogy for Chatter in Machining

    Directory of Open Access Journals (Sweden)

    Tony Schmitz

    2015-01-01

    Full Text Available This paper provides experimental evidence for the analogy between the time-delay feedback in public address systems and chatter in machining. Machining stability theory derived using the Nyquist criterion is applied to predict the squeal frequency in a microphone/speaker setup. Comparisons between predictions and measurements are presented.

  14. Effects of relay chatter in seismic probabilistic safety analysis

    International Nuclear Information System (INIS)

    Reed, J.W.; Shiu, K.K.

    1985-01-01

    In the Zion and Indian Point Probabilistic Safety Studies, relay chatter was dismissed as a credible event and hence was not formally included in the analyses. Although little discussion is given in the Zion and Indian Point PSA documentation concerning the basis for this decision, it has been expressed informally that it was assumed that the operators will be able to reset all relays in a timely manner. Currently, it is the opinion of many professionals that this may be an oversimplification. The three basic areas which must be considered in addressing relay chatter include the fragility of the relays per se, the reliability of the operators to reset the relays and finally the systems response aspects. Each of these areas is reviewed and the implications for seismic PSA are discussed. Finally, recommendations for future research are given

  15. Nuclear Physicists in Finance

    Science.gov (United States)

    Mattoni, Carlo

    2017-01-01

    The financial services industry presents an interesting alternative career path for nuclear physicists. Careers in finance typically offer intellectual challenge, a fast pace, high caliber colleagues, merit-based compensation with substantial upside, and an opportunity to deploy skills learned as a physicist. Physicists are employed at a wide range of financial institutions on both the ``buy side'' (hedge fund managers, private equity managers, mutual fund managers, etc.) and the ``sell side'' (investment banks and brokerages). Historically, physicists in finance were primarily ``quants'' tasked with applying stochastic calculus to determine the price of financial derivatives. With the maturation of the field of derivative pricing, physicists in finance today find work in a variety of roles ranging from quantification and management of risk to investment analysis to development of sophisticated software used to price, trade, and risk manage securities. Only a small subset of today's finance careers for physicists require the use of advanced math and practically none provide an opportunity to tinker with an apparatus, yet most nevertheless draw on important skills honed during the training of a nuclear physicist. Intellectually rigorous critical thinking, sophisticated problem solving, an attention to minute detail and an ability to create and test hypotheses based on incomplete information are key to both disciplines.

  16. Physicists produce first antiatom

    CERN Multimedia

    Watson, A

    1996-01-01

    Researchers at the European Center for Particle Physics (CERN) created 11 atoms of antihydrogen using the Low-Energy Antiproton Ring. Physicists forecast that the creation of the first antiatoms will aid in the understanding of antimatter.

  17. Are physicists useful?

    CERN Multimedia

    Ridley, B

    2001-01-01

    Article arguing that physicists need to be more than experts in their fields. They should develop their business, team-work and communication skills if they want to prove their worth to industry (1 page).

  18. Chatter detection in milling process based on VMD and energy entropy

    Science.gov (United States)

    Liu, Changfu; Zhu, Lida; Ni, Chenbing

    2018-05-01

    This paper presents a novel approach to detect the milling chatter based on Variational Mode Decomposition (VMD) and energy entropy. VMD has already been employed in feature extraction from non-stationary signals. The parameters like number of modes (K) and the quadratic penalty (α) need to be selected empirically when raw signal is decomposed by VMD. Aimed at solving the problem how to select K and α, the automatic selection method of VMD's based on kurtosis is proposed in this paper. When chatter occurs in the milling process, energy will be absorbed to chatter frequency bands. To detect the chatter frequency bands automatically, the chatter detection method based on energy entropy is presented. The vibration signal containing chatter frequency is simulated and three groups of experiments which represent three cutting conditions are conducted. To verify the effectiveness of method presented by this paper, chatter feather extraction has been successfully employed on simulation signals and experimental signals. The simulation and experimental results show that the proposed method can effectively detect the chatter.

  19. Quiet Areas and the Need for Quietness in Amsterdam

    Directory of Open Access Journals (Sweden)

    Hester Booi

    2012-03-01

    Full Text Available This paper describes the Quiet Places Project in Amsterdam. The purpose of the study was to find out: (1 which public quiet places there are according to Amsterdam residents; (2 what characterizes a quiet place; (3 to what extent do residents want peace and quiet; (4 how do residents realize these needs. The factors determining the need for quietness are presented in a model showing the influence of demographic and socio-economic issues, health status, sensitiveness to noise, daily activities and the noisiness in and around home. Most important of these factors is sensitivity to noise. Elderly and less healthy people are more often sensitive to noise. People who are annoyed by sound from traffic, airplanes and the like show a higher need for quietness. People with a lively household or neighbourhood report lower needs for quietness. Visiting a quiet place and going outside to walk or bike can have a compensating effect on the need for quietness. This suggests that creating quiet places and enhancing possibilities for quiet recreation in urban environments can have a positive effect on the quality of life in the city. Objective noise levels at the quiet places were taken from environmental noise maps. This shows that there may be a preference for low transportation noise levels, but levels up to 60 dB Lday are acceptable. Apparently this depends on a relative quietness or on non-acoustic characteristics of an area: the presence of vegetation and other pleasant stimuli.

  20. Women Physicists Speak Again

    Science.gov (United States)

    Ivie, Rachel; Guo, Stacy

    2005-10-01

    More than 1350 women physicists from more than 70 countries responded to a survey designed to identify issues important to women in physics. Women physicists had many areas of concern, notably discrimination and career/family balance. However, they also had many successes in physics. The majority would choose physics again and felt that they had progressed in their careers at least as quickly as their colleagues. Many spoke eloquently about their love of physics, the support they had received from others, and about their own determination and hard work.

  1. Model-based chatter stability prediction and detection for the turning of a flexible workpiece

    Science.gov (United States)

    Lu, Kaibo; Lian, Zisheng; Gu, Fengshou; Liu, Hunju

    2018-02-01

    Machining long slender workpieces still presents a technical challenge on the shop floor due to their low stiffness and damping. Regenerative chatter is a major hindrance in machining processes, reducing the geometric accuracies and dynamic stability of the cutting system. This study has been motivated by the fact that chatter occurrence is generally in relation to the cutting position in straight turning of slender workpieces, which has seldom been investigated comprehensively in literature. In the present paper, a predictive chatter model of turning a tailstock supported slender workpiece considering the cutting position change during machining is explored. Based on linear stability analysis and stiffness distribution at different cutting positions along the workpiece, the effect of the cutting tool movement along the length of the workpiece on chatter stability is studied. As a result, an entire stability chart for a single cutting pass is constructed. Through this stability chart the critical cutting condition and the chatter onset location along the workpiece in a turning operation can be estimated. The difference between the predicted tool locations and the experimental results was within 9% at high speed cutting. Also, on the basis of the predictive model the dynamic behavior during chatter that when chatter arises at some cutting location it will continue for a period of time until another specified location is arrived at, can be inferred. The experimental observation is in good agreement with the theoretical inference. In chatter detection respect, besides the delay strategy and overlap processing technique, a relative threshold algorithm is proposed to detect chatter by comparing the spectrum and variance of the acquired acceleration signals with the reference saved during stable cutting. The chatter monitoring method has shown reliability for various machining conditions.

  2. Abstract algebra for physicists

    International Nuclear Information System (INIS)

    Zeman, J.

    1975-06-01

    Certain recent models of composite hadrons involve concepts and theorems from abstract algebra which are unfamiliar to most theoretical physicists. The algebraic apparatus needed for an understanding of these models is summarized here. Particular emphasis is given to algebraic structures which are not assumed to be associative. (2 figures) (auth)

  3. Fermilab Education: Physicists

    Science.gov (United States)

    Search Education and Outreach: Resources and Opportunties for Fermilab employees and Users A variety of resources and opportunities are available for physicists interested in education and outreach (For general Data (6–12) Physical Science/Physics Instructional Resources (K–12) US Particle Physics Education and

  4. Physicists epoch and personalities

    CERN Document Server

    Feinberg, E L; Leonidov, A V

    2011-01-01

    The book is a collection of memoirs on famous Soviet physicists of the 20th century, such as Tamm, Vavilov, Sakharov, Landau and others. The narrative is situated within a remarkably well-described historical, cultural and social context. Of special interest are the chapters devoted to Soviet and German atomic projects.

  5. Mathematics for physicists

    CERN Document Server

    Martin, B R

    2015-01-01

    Mathematics for Physicists is a relatively short volume covering all the essential mathematics needed for a typical first degree in physics, from a starting point that is compatible with modern school mathematics syllabuses. Early chapters deliberately overlap with senior school mathematics, to a degree that will depend on the background of the individual reader, who may quickly skip over those topics with which he or she is already familiar. The rest of the book covers the mathematics that is usually compulsory for all students in their first two years of a typical university physics degree, plus a little more. There are worked examples throughout the text, and chapter-end problem sets. Mathematics for Physicists features: * Interfaces with modern school mathematics syllabuses * All topics usually taught in the first two years of a physics degree * Worked examples throughout * Problems in every chapter, with answers to selected questions at the end of the book and full solutions on a website This text will ...

  6. Euler as Physicist

    CERN Document Server

    Suisky, Dieter

    2008-01-01

    "Euler as Physicist" analyzes the exceptional role of Leonhard Euler (1707 - 1783) in the history of science and emphasizes especially his fundamental contributions to physics. Although Euler is famous as the leading mathematician of the 18th century, his contributions to physics are as important for their innovative methods and solutions. Several books are devoted to Euler as mathematician, but none to Euler as physicist, like in this book. Euler’s contributions to mechanics are rooted in his life-long plan presented in two volume treatise programmatically entitled "Mechanics or the science of motion analytically demonstrated". Published in 1736, Euler’s treatise indicates the turn over from the traditional geometric representation of mechanics to a new approach. In writing Mechanics Euler did the first step to put the plan and his completion into practice through 1760. It is of particular interest to study how Euler made immediate use of his mathematics for mechanics and coordinated his progress in math...

  7. Physicists in the Wild

    Science.gov (United States)

    Miller, Michael L.

    2017-09-01

    Startups and large corporations are full of physicists, many hiding in plain sight. Why? I will discuss the strong parallels between basic research in nuclear/particle physics, founding teams at great startups, and leaders at some of the world's largest corporations. How big are these opportunities (mission and capital), and what can we do to help prepare more physicists for such roles? I will provide lessons learned from my winding career that began at the NSCL as a philosophy undergrad, proceeded through a PhD, postdoc and brief stint as faculty, and continued through the founding of an early cloud computing startup, a sale to IBM, and the founding of one of Silicon Valley's most active venture capital firms.

  8. Detection of auditory signals in quiet and noisy backgrounds while performing a visuo-spatial task

    Directory of Open Access Journals (Sweden)

    Vishakha W Rawool

    2016-01-01

    Full Text Available Context: The ability to detect important auditory signals while performing visual tasks may be further compounded by background chatter. Thus, it is important to know how task performance may interact with background chatter to hinder signal detection. Aim: To examine any interactive effects of speech spectrum noise and task performance on the ability to detect signals. Settings and Design: The setting was a sound-treated booth. A repeated measures design was used. Materials and Methods: Auditory thresholds of 20 normal adults were determined at 0.5, 1, 2 and 4 kHz in the following conditions presented in a random order: (1 quiet with attention; (2 quiet with a visuo-spatial task or puzzle (distraction; (3 noise with attention and (4 noise with task. Statistical Analysis: Multivariate analyses of variance (MANOVA with three repeated factors (quiet versus noise, visuo-spatial task versus no task, signal frequency. Results: MANOVA revealed significant main effects for noise and signal frequency and significant noise–frequency and task–frequency interactions. Distraction caused by performing the task worsened the thresholds for tones presented at the beginning of the experiment and had no effect on tones presented in the middle. At the end of the experiment, thresholds (4 kHz were better while performing the task than those obtained without performing the task. These effects were similar across the quiet and noise conditions. Conclusion: Detection of auditory signals is difficult at the beginning of a distracting visuo-spatial task but over time, task learning and auditory training effects can nullify the effect of distraction and may improve detection of high frequency sounds.

  9. Young physicists' forum

    International Nuclear Information System (INIS)

    Adams, T.

    2001-01-01

    The Young Physicists' Forum was an opportunity for the younger members of the particle-physics community to gather at Snowmass 2001 and to study and debate major issues that face the field over the next twenty years. Discussions were organized around three major topics: outreach and education, the impact of globalization, and building a robust and balanced field. We report on the results of these discussions, as presented on July 17, 2001

  10. Physicist or computer specialist?

    Energy Technology Data Exchange (ETDEWEB)

    Clifton, J S [University College Hospital, London (United Kingdom)

    1966-06-15

    Since to most clinicians physical and computer science are two of the great mysteries of the world, the physicist in a hospital is expected by clinicians to be fully conversant with, and competent to make profound pronouncements on, all methods of computing. specific computing problems, and the suitability of computing machinery ranging from desk calculators to Atlas. This is not surprising since the proportion of the syllabus devoted to physics and mathematics in an M. B. degree is indeed meagre, and the word 'computer' has been surrounded with an aura of mysticism which suggests that it is some fantastic piece of electronic gadgetry comprehensible only to a veritable genius. The clinician consequently turns to the only scientific colleague with whom he has direct contact - the medical physicist - and expects him to be an authority. The physicist is thus thrust, however unwillingly, into the forefront of the advance of computer assistance to scientific medicine. It is therefore essential for him to acquire sufficient knowledge of computing science to enable him to provide satisfactory answers for the clinicianst queries, to proffer more detailed advice as to programming convince clinicians that the computer is really a 'simpleton' which can only add and subtract and even that only under instruction.

  11. Fuzzy sliding-mode control with low pass filter to reduce chattering ...

    Indian Academy of Sciences (India)

    S Balamurugan

    2017-10-13

    Oct 13, 2017 ... effect: an experimental validation on Quanser SRIP ... Stabilization of a single rotary inverted pendulum (SRIP) system is a benchmark nonlinear control problem. ..... SMC with sign function still exhibits the chattering phe-.

  12. Chattering-free fuzzy sliding-mode control strategy for uncertain chaotic systems

    International Nuclear Information System (INIS)

    Yau, H.-T.; Chen, C.-L.

    2006-01-01

    This paper proposes a chattering-free fuzzy sliding-mode control (FSMC) strategy for uncertain chaotic systems. A fuzzy logic control is used to replace the discontinuous sign function of the reaching law in traditional sliding-mode control (SMC), and hence a control input without chattering is obtained in the chaotic systems with uncertainties. Base on the Lyapunov stability theory, we address the design schemes of integration fuzzy sliding-mode control, where the reaching law is proposed by a set of linguistic rules and the control input is chattering free. The Genesio chaotic system is used to test the proposed control strategy and the simulation results show the FSMC not only can control the uncertain chaotic behaviors to a desired state without oscillator very fast, but also the switching function is smooth without chattering. This result implies that this strategy is feasible and effective for chaos control

  13. The last universal physicist

    Energy Technology Data Exchange (ETDEWEB)

    Coccia, Eugenio [Gran Sasso National Laboratory, University of Rome ' Tor Vergata' (Italy)]. E-mail coccia@lngs.infn.it

    2005-04-01

    Born in Rome in 1901, Fermi was the last universal physicist - the most extraordinary of his century. He was at home in the workshop, the laboratory and among theoretical physicists. For the theorists he was a great theorist, and for the experimentalists he was a great experimentalist. What made Fermi so special as a physicist was his universality and versatility; what made him so special as a person was his modesty, realism and frugal lifestyle. This book, which describes Fermi's contributions to physics and the US period of his life, originated from a symposium that was held in Chicago in 2001 to commemorate the centenary of his birth. But it is not merely a volume of reminiscences. It combines essays, specially commissioned articles, as well as private material from Fermi's research notebooks, correspondence and speeches. Together the material highlights the breadth of his impact on physics. A classic biographical introduction by Emilio Segre is followed by an article in which Frank Wilczek, who shared the Nobel Prize for Physics last year, puts into perspective Fermi's huge contributions to physics. The list of his achievements is impressive. They include the introduction of Fermi statistics for half-integer-spin particles (1925) - now called fermions - that led to the concept of the 'Fermi surface' in condensed-matter and nuclear physics; the vector-coupling theory for beta-decay (1933), which formulated the proper structure of the weak interaction where the 'Fermi constant' measures the strength of the coupling; and the introduction, with his Rome group, of neutron-induced radioactivity and the study of slow-neutron interactions (1934). As a researcher and a teacher, Fermi inspired two generations and two continents - a man whose charismatic nature attracted many talented scientists and students to Chicago. What emerges from this book is the gratitude of so many extraordinary physicists to their master, who instilled in them

  14. Experimental Investigation of Chatter Dynamics in Thin-walled Tubular Parts Turning

    OpenAIRE

    GERASIMENKO, Artem; GUSKOV, Mikhail; LORONG, Philippe; DUCHEMIN, Jérôme; GOUSKOV, Alexander

    2016-01-01

    Chatter prediction is nowadays frequently carried out for machining operations involving deformable parts or tools. These analyses are commonly based on the uncoupled elements of the system: frequency response of the deformable parts under non-rotating conditions and cutting law. The present investigation puts forward the dynamics of a thin-walled tubular part during straight axial turning undergoing chatter instability. Studied system’s peculiarities include quasi-static nominal cutting cond...

  15. Female physicist doctoral experiences

    Directory of Open Access Journals (Sweden)

    Katherine P. Dabney

    2013-04-01

    Full Text Available The underrepresentation of women in physics doctorate programs and in tenured academic positions indicates a need to evaluate what may influence their career choice and persistence. This qualitative paper examines eleven females in physics doctoral programs and professional science positions in order to provide a more thorough understanding of why and how women make career choices based on aspects both inside and outside of school and their subsequent interaction. Results indicate that female physicists experience conflict in achieving balance within their graduate school experiences and personal lives and that this then influences their view of their future careers and possible career choices. Female physicists report both early and long-term support outside of school by family, and later departmental support, as being essential to their persistence within the field. A greater focus on informal and out-of-school science activities for females, especially those that involve family members, early in life may help influence their entrance into a physics career later in life. Departmental support, through advisers, mentors, peers, and women’s support groups, with a focus on work-life balance can help females to complete graduate school and persist into an academic career.

  16. Female physicist doctoral experiences

    Science.gov (United States)

    Dabney, Katherine P.; Tai, Robert H.

    2013-06-01

    The underrepresentation of women in physics doctorate programs and in tenured academic positions indicates a need to evaluate what may influence their career choice and persistence. This qualitative paper examines eleven females in physics doctoral programs and professional science positions in order to provide a more thorough understanding of why and how women make career choices based on aspects both inside and outside of school and their subsequent interaction. Results indicate that female physicists experience conflict in achieving balance within their graduate school experiences and personal lives and that this then influences their view of their future careers and possible career choices. Female physicists report both early and long-term support outside of school by family, and later departmental support, as being essential to their persistence within the field. A greater focus on informal and out-of-school science activities for females, especially those that involve family members, early in life may help influence their entrance into a physics career later in life. Departmental support, through advisers, mentors, peers, and women’s support groups, with a focus on work-life balance can help females to complete graduate school and persist into an academic career.

  17. C++ for Particle Physicists

    CERN Multimedia

    Monique Duval

    2002-01-01

    Paul Kunz will be giving his very popular and highly recommended C++ course again on 22-26 July (6 * 3 hour lectures). The course is organised by the CERN Technical Training Programme, it costs 200 CHF, and advance registration is required. People with CERN EDH accounts can apply electronically directly from the Web course description page, accessible from the Technical Training pages. Team Visitors should ask their Group Leader to send an e-mail to the DTO of EP Division, M. Burri, referring to the 'C++ for Particle Physicists' course and giving their name, CERN ID number, the Team account number to which the course fee should be charged, and VERY IMPORTANTLY an email address to which an invitation to the course can be sent.

  18. C++ for Particle Physicists

    CERN Multimedia

    2003-01-01

    Please note that Paul Kunz will be giving his very popular and highly recommended C++ course again on 10 - 14 March. The course costs 200 CHF, and advance registration is required. People with CERN EDH accounts can apply electronically directly from the Web course description page : http://cern.ch/TechnicalTraining/ENSTEC/p2002/Software/cpppp_e.asp Team Visitors should ask their Group Leader to send an e-mail to the DTO of EP Division, M. Burri, referring to the 'C++ for Particle Physicists' course and giving their name, CERN ID number, the Team account number to which the course fee should be charged, and VERY IMPORTANTLY an email address to which an invitation to the course can be sent.

  19. C++ FOR PARTICLE PHYSICISTS

    CERN Multimedia

    Monique Duval

    2002-01-01

    Paul Kunz will be giving his very popular and highly recommended C++ course again on 22-26 July (6 * 3 hour lectures). The course is organised by the CERN Technical Training Programme, it costs 200 CHF, and advance registration is required. People with CERN EDH accounts can apply electronically directly from the Web course description page, accessible from the Technical Training pages. Team Visitors should ask their Group Leader to send an e-mail to the DTO of EP Division, M. Burri, referring to the 'C++ for Particle Physicists' course and giving their name, CERN ID number, the Team account number to which the course fee should be charged, and VERY IMPORTANTLY an email address to which an invitation to the course can be sent.

  20. C++ for Particle Physicists

    CERN Multimedia

    Technical Training; Tel. 74924

    2001-01-01

    Paul Kunz will be giving his very popular and highly recommended C++ course again on 8 - 12 October. The course costs 200 CHF, and advance registration is required. Please note that this will be the last session in 2001 and the next one is planned for March 2002. People with CERN EDH accounts can apply electronically directly from the Web course description page : http://www.cern.ch/Training/ENSTEC/P2001/Software/cpppp_e.htm   Team Visitors should ask their Group Leader to send an e-mail to the DTO of EP Division, M. Burri, referring to the 'C++ for Particle Physicists' course and giving their name, CERN ID number, the Team account number to which the course fee should be charged, and VERY IMPORTANTLY an email address to which an invitation to the course can be sent.

  1. C++ FOR PARTICLE PHYSICISTS

    CERN Multimedia

    TECHNICAL TRAINING; Tel. 74460

    2001-01-01

    Please note that Paul Kunz will be giving his very popular and highly recommended C++ course again on March 5 to 9. The course costs 200 CHF, and advance registration is required. People with CERN EDH accounts can apply electronically directly from the Web course description page : http://www.cern.ch/Training/ENSTEC/P9798/Software/cpppp_e.htm Team Visitors should ask their Group Leader to send an e-mail to the DTO of EP Division, M. Burri, referring to the 'C++ for Particle Physicists' course and giving their name, CERN ID number, the Team account number to which the course fee should be charged, and VERY IMPORTANTLY an email address to which an invitation to the course can be sent.

  2. Caverns for neutrino physicists

    International Nuclear Information System (INIS)

    Duffaut, P.

    2005-01-01

    Since more than 20 years, particle physicists are using underground facilities to catch cosmic neutrinos and to get rid of other parasitic cosmic radiations. The observation of significant numbers of neutrinos requires the use of large volume caverns at important depths. This article presents such existing facilities in the US, France, Italy, UK, Spain, Japan (Kamioka), Russia and India and the different projects in competition for the setting up of a mega-ton detector with a volume of 1 million m 3 of water (DUSEL project in the US, MEMPHYS project in France, Hyperkamiokande in Japan). Several suitable underground spaces are available in these countries (abandoned mines, tunnels) but each has its advantages and drawbacks in terms of rock mechanics, access and seismicity. (J.S.)

  3. Physicists get INSPIREd

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    Particle physicists thrive on information. They first create information by performing experiments or elaborating theoretical conjectures and then they share it through publications and various web tools. The INSPIRE service, just released, will bring state of the art information retrieval to the fingertips of researchers.   Keeping track of the information shared within the particle physics community has long been the task of libraries at the larger labs, such as CERN, DESY, Fermilab and SLAC, as well as the focus of indispensible services like arXiv and those of the Particle Data Group. In 2007, many providers of information in the field came together for a summit at SLAC to see how physics information resources could be enhanced, and the INSPIRE project emerged from that meeting. The vision behind INSPIRE was built by a survey launched by the four labs to evaluate the real needs of the community. INSPIRE responds to these directives from the community by combining the most successful aspe...

  4. C++ for Particle Physicists

    CERN Multimedia

    Monique Duval

    2004-01-01

    Please note that Paul Kunz will be giving his very popular and highly recommended C++ course again on 15 �- 19 November. The course costs 200 CHF, and advance registration is required. People with CERN EDH accounts can apply electronically directly from the Web course description page: Team Visitors should ask their Group Leader to send an e-mail to the DTO of PH Department, M. Burri, referring to the 'C++ for Particle Physicists' course and giving their name, CERN ID number, the Team account number to which the course fee should be charged, and VERY IMPORTANTLY an email address to which an invitation to the course can be sent. ENSEIGNEMENT TECHNIQUE TECHNICAL TRAINING Monique Duval 74924 technical.training@cern.ch

  5. C++ for Particle Physicists

    CERN Multimedia

    Monique Duval

    2004-01-01

    Please note that Paul Kunz will be giving his very popular and highly recommended C++ course again on 15 - 19 November. The course costs 200 CHF, and advance registration is required. People with CERN EDH accounts can apply electronically directly from the Web course description page: Team Visitors should ask their Group Leader to send an e-mail to the DTO of PH Department, M. Burri, referring to the 'C++ for Particle Physicists' course and giving their name, CERN ID number, the Team account number to which the course fee should be charged, and VERY IMPORTANTLY an email address to which an invitation to the course can be sent. ENSEIGNEMENT TECHNIQUE TECHNICAL TRAINING Monique Duval 74924 technical.training@cern.ch

  6. Objective comparison of 4 nonlongitudinal ultrasound modalities regarding efficiency and chatter.

    Science.gov (United States)

    DeMill, David L; Zaugg, Brian E; Pettey, Jeff H; Jensen, Jason D; Jardine, Griffin J; Wong, Gilbert; Olson, Randall J

    2012-06-01

    To compare efficiency and chatter of Infiniti Ozil with and without Intelligent Phacoemulsification (IP) and the Signature Ellips with and without FX. John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Experimental study. Brunescent 2.0 mm human lens cubes were created by an instrument devised for this study. Cubes were tested (10 per test) for time of particle removal (efficiency) and for the number of times the lens particle bounced off the tip (chatter) at 300 mm Hg and 550 mm Hg, 50% and 100% power, and 50% and 100% amplitudes (amplitude for Ozil only). Of the ultrasound settings, efficiency varied from a mean of 3.3 seconds ± 1.4 (SD) to 50.4 ± 11.7 seconds and chatter from 0.0 to 52.0 ± 16.7 bounces per run. The Ozil-IP was generally more efficient than the Ozil and the Ellips FX more efficient than the Ellips. At optimized values, the Ozil-IP and Ellips-FX were similar. In general, efficiency and chatter were better at 550 mm Hg and at 50% power. The amplitude effect was complex. Efficiency closely correlated with chatter (Pearson r(2) = .31, P<.0001). Objective comparison of phacoemulsification efficiency and chatter found that optimized Ozil-IP and Ellips-FX were similar in both parameters and in general, both performed better than preceding technology. The study parameters can significantly affect efficiency and chatter, which strongly correlate with each other. Copyright © 2012 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  7. What is a medical physicist?

    International Nuclear Information System (INIS)

    Endo, Masahiro

    2011-01-01

    The modern radiotherapy requires a medical physicist who optimizes treatment plans, assures delivered dose equal to prescription, and performs QA (quality assurance) of radiotherapy equipments. However, medical physicist has not been established as a medical profession in Japan mainly because importance of radiotherapy was not sufficiently recognized until recently. Between 2000 and 2004, several accidents of radiotherapy including hundreds of patients were found and these accidents were mainly caused by lack of QA. The necessity and importance of medical physicist were recognized by these accidents as well as by the advent of high-precision radiotherapy such as IMRT (intensity modulation radiation therapy). JRS (Japan Radiological Society) that certified medical physicists with the help of JSMP (Japan Society of Medical Physics), decided to extend eligibility in order to increase certified medical physicists rapidly in 2003. After the decision certified medical physicists were rapidly increased in number. The government supports this tendency to enact that certified medical physicists is necessary to reimbursement for high-precision therapy. It also started to supply grants for medical physics training in physical and health science graduate schools. In this program several universities have started medical physics course in their graduate schools. If these movements continue, medical physicist will be established as a medical profession in the near future. (author)

  8. The health physicist abroad

    International Nuclear Information System (INIS)

    Stewart, N.G.

    1980-01-01

    As health physics research teams at Harwell found adequate solutions to some of the problems in radiological protection and other spheres of nuclear technology, a mixed research programme consisting of both nuclear and non-nuclear research was undertaken by the health physics research teams since 1968 at Harwell with the aim of retaining radiological research experience. This policy widened the scope and interests of the health physicists and subsequently it was observed that particularly in the field of environment and toxicology, the division between nuclear and non-nuclear research is an artificial one. For example, the techniques developed and skills acquired to study the uptake and metabolism of radioactive aerosols were employed to study inhalation toxicology of lead aerosols from motor vehicles and their deposition on the plant and soil surfaces, influence of particle size on deposition and uptake of lead by man and plants. These techniques and skills were redeployed on new radiological problems as they arose, for example, to study the deposition and resuspension of plutonium from land and water surfaces to provide data appropriate to European conditions. Some such more examples from the work of the Environmental and Medical Sciences Division at Harwell are given. (M.G.B.)

  9. ATLAS Physicist in Space

    CERN Multimedia

    Bengt Lund-Jensen

    2007-01-01

    On December 9, the former ATLAS physicist Christer Fuglesang was launched into space onboard the STS-116 Space Shuttle flight from Kennedy Space Center in Florida. Christer worked on the development of the accordion-type liquid argon calorimeter and SUSY simulations in what eventually became ATLAS until summer 1992 when he became one out of six astronaut trainees with the European Space Agency (ESA). His selection out of a very large number of applicants from all over the ESA member states involved a number of tests in order to choose the most suitable candidates. As ESA astronaut Christer trained with the Russian Soyuz programme in Star City outside of Moscow from 1993 until 1996, when he moved to Houston to train for space shuttle missions with NASA. Christer belonged to the backup crew for the Euromir95 mission. After additional training in Russia, Christer qualified as ‘Soyuz return commander’ in 1998. Christer rerouting cables during his second space walk. (Photo: courtesy NASA) During...

  10. Summertime for physicists

    CERN Multimedia

    2013-01-01

    Summer for particle physicists is the season for “summer conferences” and the past week saw two big meetings in full swing. The 2013 European Physical Society High-Energy Physics (EPS-HEP) conference took place in Stockholm, Sweden, while the Strangeness in Quark Matter conference visited Birmingham in the UK for its 2013 edition.   Such conferences usually mark the culmination of months of hard work to prepare new results and, if nature is kind, they also provide the stage for the announcement of discoveries. But more than that, they allow people to network with colleagues from far and wide. I was at EPS-HEP, which belies its name and, like particle physics itself, has a global reach, with people attending from Asia and the Americas. This year there were some 750 attendees, including many young people. The programme of parallel sessions allowed many of them to present results they had worked on in what can be huge collaborations. It’s impressive to see their eff...

  11. Active chatter suppression with displacement-only measurement in turning process

    Science.gov (United States)

    Ma, Haifeng; Wu, Jianhua; Yang, Liuqing; Xiong, Zhenhua

    2017-08-01

    Regenerative chatter is a major hindrance for achieving high quality and high production rate in machining processes. Various active controllers have been proposed to mitigate chatter. However, most of existing controllers were developed on the basis of multi-states feedback of the system and state observers were usually needed. Moreover, model parameters of the machining process (mass, damping and stiffness) were required in existing active controllers. In this study, an active sliding mode controller, which employs a dynamic output feedback sliding surface for the unmatched condition and an adaptive law for disturbance estimation, is designed, analyzed, and validated for chatter suppression in turning process. Only displacement measurement is required by this approach. Other sensors and state observers are not needed. Moreover, it facilitates a rapid implementation since the designed controller is established without using model parameters of the turning process. Theoretical analysis, numerical simulations and experiments on a computer numerical control (CNC) lathe are presented. It shows that the chatter can be substantially attenuated and the chatter-free region can be significantly expanded with the presented method.

  12. The QUIET Instrument

    Energy Technology Data Exchange (ETDEWEB)

    Bischoff, C.; et al.

    2012-07-01

    The Q/U Imaging ExperimenT (QUIET) is designed to measure polarization in the Cosmic Microwave Background, targeting the imprint of inflationary gravitational waves at large angular scales ({approx}1{sup o}). Between 2008 October and 2010 December, two independent receiver arrays were deployed sequentially on a 1.4m side-fed Dragonian telescope. The polarimeters which form the focal planes use a highly compact design based on High Electron Mobility Transistors (HEMTs) that provides simultaneous measurements of the Stokes parameters Q, U, and I in a single module. The 17-element Q-band polarimeter array, with a central frequency of 43.1 GHz, has the best sensitivity (69 {mu}Ks{sup 1/2}) and the lowest instrumental systematic errors ever achieved in this band, contributing to the tensor-to-scalar ratio at r < 0:1. The 84-element W-band polarimeter array has a sensitivity of 87 {mu}Ks{sup 1/2} at a central frequency of 94.5 GHz. It has the lowest systematic errors to date, contributing at r < 0:01. The two arrays together cover multipoles in the range {ell} {approx} 25 -- 975. These are the largest HEMT-based arrays deployed to date. This article describes the design, calibration, performance of, and sources of systematic error for the instrument.

  13. Are physicists' philosophies irrelevant idiosyncrasies?

    NARCIS (Netherlands)

    de Regt, H.W.|info:eu-repo/dai/nl/112827802

    1996-01-01

    This article argues that individual philosophical commitments of scientists can decisively influence scientific practice. To support this claim, two historical examples are presented, concerning controversies between physicists about central problems in their field. Confrontation of the theories of

  14. Japanese physicist during the war

    International Nuclear Information System (INIS)

    Brown, L.; Nambu, Y.

    1999-01-01

    The japanese interest for the science is comparatively recent and one of the first japanese physicist is Hantoro Nagaoka with an atomic model in 1903. During the war the physicist take refuge in the theory and two universities proper in spite of difficult working conditions. This paper goes over the historical aspects of the japanese scientific research and contributions to the nucleus physic. (A.L.B.)

  15. Topology and geometry for physicists

    CERN Document Server

    Nash, Charles

    1983-01-01

    Differential geometry and topology are essential tools for many theoretical physicists, particularly in the study of condensed matter physics, gravity, and particle physics. Written by physicists for physics students, this text introduces geometrical and topological methods in theoretical physics and applied mathematics. It assumes no detailed background in topology or geometry, and it emphasizes physical motivations, enabling students to apply the techniques to their physics formulas and research. ""Thoroughly recommended"" by The Physics Bulletin, this volume's physics applications range fr

  16. Chatter suppression methods of a robot machine for ITER vacuum vessel assembly and maintenance

    International Nuclear Information System (INIS)

    Wu, Huapeng; Wang, Yongbo; Li, Ming; Al-Saedi, Mazin; Handroos, Heikki

    2014-01-01

    Highlights: •A redundant 10-DOF serial-parallel hybrid robot for ITER assembly and maintains is presented. •A dynamic model of the robot is developed. •A feedback and feedforward controller is presented to suppress machining vibration of the robot. -- Abstract: In the process of assembly and maintenance of ITER vacuum vessel (ITER VV), various machining tasks including threading, milling, welding-defects cutting and flexible hose boring are required to be performed from inside of ITER VV by on-site machining tools. Robot machine is a promising option for these tasks, but great chatter (machine vibration) would happen in the machining process. The chatter vibration will deteriorate the robot accuracy and surface quality, and even cause some damages on the end-effector tools and the robot structure itself. This paper introduces two vibration control methods, one is passive and another is active vibration control. For the passive vibration control, a parallel mechanism is presented to increase the stiffness of robot machine; for the active vibration control, a hybrid control method combining feedforward controller and nonlinear feedback controller is introduced for chatter suppression. A dynamic model and its chatter vibration phenomena of a hybrid robot is demonstrated. Simulation results are given based on the proposed hybrid robot machine which is developed for the ITER VV assembly and maintenance

  17. Chatter suppression methods of a robot machine for ITER vacuum vessel assembly and maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Huapeng; Wang, Yongbo, E-mail: yongbo.wang@lut.fi; Li, Ming; Al-Saedi, Mazin; Handroos, Heikki

    2014-10-15

    Highlights: •A redundant 10-DOF serial-parallel hybrid robot for ITER assembly and maintains is presented. •A dynamic model of the robot is developed. •A feedback and feedforward controller is presented to suppress machining vibration of the robot. -- Abstract: In the process of assembly and maintenance of ITER vacuum vessel (ITER VV), various machining tasks including threading, milling, welding-defects cutting and flexible hose boring are required to be performed from inside of ITER VV by on-site machining tools. Robot machine is a promising option for these tasks, but great chatter (machine vibration) would happen in the machining process. The chatter vibration will deteriorate the robot accuracy and surface quality, and even cause some damages on the end-effector tools and the robot structure itself. This paper introduces two vibration control methods, one is passive and another is active vibration control. For the passive vibration control, a parallel mechanism is presented to increase the stiffness of robot machine; for the active vibration control, a hybrid control method combining feedforward controller and nonlinear feedback controller is introduced for chatter suppression. A dynamic model and its chatter vibration phenomena of a hybrid robot is demonstrated. Simulation results are given based on the proposed hybrid robot machine which is developed for the ITER VV assembly and maintenance.

  18. Analytical expressions for chatter analysis in milling operations with one dominant mode

    Science.gov (United States)

    Iglesias, A.; Munoa, J.; Ciurana, J.; Dombovari, Z.; Stepan, G.

    2016-08-01

    In milling, an accurate prediction of chatter is still one of the most complex problems in the field. The presence of these self-excited vibrations can spoil the surface of the part and can also cause a large reduction in tool life. The stability diagrams provide a practical selection of the optimum cutting conditions determined either by time domain or frequency domain based methods. Applying these methods parametric or parameter traced representations of the linear stability limits can be achieved by solving the corresponding eigenvalue problems. In this work, new analytical formulae are proposed related to the parameter domains of both Hopf and period doubling type stability boundaries emerging in the regenerative mechanical model of time periodical milling processes. These formulae are useful to enrich and speed up the currently used numerical methods. Also, the destabilization mechanism of double period chatter is explained, creating an analogy with the chatter related to the Hopf bifurcation, considering one dominant mode and using concepts established by the Pioneers of chatter research.

  19. Automatic in-process chatter avoidance in the high-speed milling process

    NARCIS (Netherlands)

    Dijk, van N.J.M.; Doppenberg, E.J.J.; Faassen, R.P.H.; Wouw, van de N.; Oosterling, J.A.J.; Nijmeijer, H.

    2010-01-01

    High-speed milling is often used in industry to maximize productivity of the manufacturing of high-technology components, such as aeronautical components, mold, and dies. The occurrence of chatter highly limits the efficiency and accuracy of high-speed milling operations. In this paper, two control

  20. Perspective for Female Medical Physicists

    International Nuclear Information System (INIS)

    Naqvi, Syed Mansoor; Hasnain, Aziz Fatima

    2009-01-01

    Due to cultural and religious reasons, Pakistani women can be reluctant to seek medical attention for disorders affecting their genitals or breasts. As a result, in the case of cervical and breast cancers, oncological treatment is often not received until the diseases are in the late stages. Once a cancer is classified and the tumor marked, the role of the medical physicist begins. Medical physicists' responsibilities include treatment planning, supervising treatment through radiation, dosimetry, contouring, training, equipment selection, education, research, and supervising radiotherapy facilities. In brachytherapy, isotopes are placed at the tumor site in the form of wires or seeds. There are very few female medical physicists in Pakistan. This leads to further hesitation on the part of many women to seek treatment. To help female patients obtain needed medical care, female physics students should be encouraged to pursue the emerging field of medical physics. This would provide a new professional opportunity for female physics students and give comfort to female patients.

  1. Complementary Colours for a Physicist

    Science.gov (United States)

    Babic, Vitomir; Cepic, Mojca

    2009-01-01

    This paper reports on a simple experiment which enables splitting incident light into two different modes, each having a colour exactly complementary to the other. A brief historical development of colour theories and differences in a physicist's point of view with respect to an artist's one is discussed. An experimental system for producing…

  2. Nuclear physicist, arms control advocate

    CERN Multimedia

    Chang, K

    2002-01-01

    Victor F. Weisskopf, a nuclear physicist who worked on the Manhattan Project to build the first atomic bomb in World War II and later became an ardent advocate of arms control, died Monday at his home in Newton, MA, USA. He was 93 (1 page).

  3. LHC Olympics flex physicists' brains

    CERN Multimedia

    2006-01-01

    Physicists from around the world met at CERN to strengthen their data-deciphering skills at the second LHC Olympics workshop. Physicists gather for the second LHC Olympics workshop. Coinciding with the kick-off of the winter Olympics in Turin, more than 70 physicists gathered at CERN from across the globe for the second LHC Olympics workshop on 9-10 February. Their challenge, however, involved brains rather than brawn. As the switch-on date for the LHC draws near, scientists excited by the project want to test and improve their ability to decipher the unprecedented amount of data that the world's biggest and most powerful particle accelerator is expected to generate. The LHC Olympics is a coordinated effort to do just that, minus the gold, silver and bronze of the athletics competition. 'In some ways, the LHC is not a precision instrument. It gives you the information that something is there but it's hard to untangle and interpret what it is,' said University of Michigan physicist Gordy Kane, who organiz...

  4. A Physicist Looks at Biology

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 11. A Physicist Looks at Biology. Max Delbrück. Classics Volume 4 Issue 11 November 1999 pp 89-102. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/004/11/0089-0102. Author Affiliations.

  5. Mathematics for Physicists and Engineers.

    Science.gov (United States)

    Organisation for Economic Cooperation and Development, Paris (France).

    The text is a report of the OEEC Seminar on "The Mathematical Knowledge Required by the Physicist and Engineer" held in Paris, 1961. There are twelve major papers presented: (1) An American Parallel (describes the work of the Panel on Physical Sciences and Engineering of the Committee on the Undergraduate Program in Mathematics of the Mathematical…

  6. Quiet Moment around the Campfire

    Centers for Disease Control (CDC) Podcasts

    2014-06-18

    Byron Breedlove reads his essay, "Quiet Moment around the Campfire," about the art of Frederic Remington and the transmission of pathogens as frontiers expand.  Created: 6/18/2014 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 6/19/2014.

  7. Sliding mode controller gain adaptation and chattering reduction techniques for DSP-based PM DC motor drives

    DEFF Research Database (Denmark)

    Dal, Mehmet; Teodorescu, Remus

    2011-01-01

    In order to achieve and maintain the prospective benefits of sliding mode control (SMC) methodology, the phenomenon known as “chattering”, the main obstacle encountered in real-time applications, has to be suppressed. In this study, two promising switching control gain adaptation and chattering...... reduction techniques are investigated, and the effectiveness of chattering suppression for current regulation of PM DC drives is tested. The sampling rate was also examined to determine how it affects the amplitude of chattering. This paper concentrates on various combinations of observer-based methods...... in order to find the best solution for chattering reduction. To find a practical solution a tunable low-pass filter (LPF) was used to average the discontinuous control term. The validity of the existing conditions for the gain adaptation methods are examined and observer gain value was determined through...

  8. Influence of Chatter of VMC Arising During End Milling Operation and Cutting Conditions on Quality of Machined Surface

    Directory of Open Access Journals (Sweden)

    A.K.M.N. Amin, M.A. Rizal, and M. Razman

    2012-08-01

    Full Text Available Machine tool chatter is a dynamic instability of the cutting process. Chatter results in poor part surface finish, damaged cutting tool, and an irritating and unacceptable noise. Exten¬sive research has been undertaken to study the mechanisms of chatter formation. Efforts have been also made to prevent the occurrence of chatter vibration. Even though some progress have been made, fundamental studies on the mechanics of metal cutting are necessary to achieve chatter free operation of CNC machine tools to maintain their smooth operating cycle. The same is also true for Vertical Machining Centres (VMC, which operate at high cutting speeds and are capable of offering high metal removal rates. The present work deals with the effect of work materials, cutting conditions and diameter of end mill cutters on the frequency-amplitude characteristics of chatter and on machined surface roughness. Vibration data were recorded using an experimental rig consisting of KISTLER 3-component dynamometer model 9257B, amplifier, scope meters and a PC.  Three different types of vibrations were observed. The first type was a low frequency vibration, associated with the interrupted nature of end mill operation. The second type of vibration was associated with the instability of the chip formation process and the third type was due to chatter. The frequency of the last type remained practically unchanged over a wide range of cutting speed.  It was further observed that chip-tool contact processes had considerable effect on the roughness of the machined surface.Key Words: Chatter, Cutting Conditions, Stable Cutting, Surface Roughness.

  9. Robust Non-Chattering Observer Based Sliding Control Concept for Electro-Hydraulic Drives

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.

    2013-01-01

    This paper presents an observer-based sliding mode control concept with chattering reduction, generally applicable for position tracking control of electro-hydraulic valve-cylinder drives (VCD's). The proposed control concept requires only common data sheet information and no knowledge on load...... extensive knowledge on system parameters nor advanced control theory. In order to accomplish this task, an integral sliding mode controller designed for the control derivative employing state observation is proposed, based on a generalized reduced order model structure of a VCD with unmatched valve ow......- and cylinder asymmetries. It is shown that limited attention can be given to bounds on parameter estimates, that chattering is reduced and the number of tuning parameters is reduced to the level seen in conventional PID schemes. Furthermore, simulation results demonstrate a high level of robustness when...

  10. A dynamic model of cylindrical plunge grinding process for chatter phenomena investigation

    Directory of Open Access Journals (Sweden)

    Lajmert Paweł

    2018-01-01

    Full Text Available In the paper, chatter vibrations in the cylindrical plunge grinding process are investigated. An improved model of the grinding process was developed which is able to simulate self-excited vibrations due to a regenerative effect on the workpiece and the grinding wheel surface. The model includes a finite-element model of the workpiece, two degrees of freedom model of the grinding wheel headstock and a model of wheel-workpiece geometrical interferences. The model allows to studying the influence of different factors, i.e. workpiece and machine parameters as well as grinding conditions on the stability limit and a chatter vibration growth rate. At the end, simulation results are shown and compared with exemplified real grinding results.

  11. Delay dynamical systems and applications to nonlinear machine-tool chatter

    International Nuclear Information System (INIS)

    Fofana, M.S.

    2003-01-01

    The stability behaviour of machine chatter that exhibits Hopf and degenerate bifurcations has been examined without the assumption of small delays between successive cuts. Delay dynamical system theory leading to the reduction of the infinite-dimensional character of the governing delay differential equations (DDEs) to a finite-dimensional set of ordinary differential equations have been employed. The essential mathematical arguments for these systems in the context of retarded DDEs are summarized. Then the application of these arguments in the stability study of machine-tool chatter with multiple time delays is presented. Explicit analytical expressions ensuring stable and unstable machining when perturbations are periodic, stochastic and nonlinear have been derived using the integral averaging method and Lyapunov exponents

  12. Physicists' Forced Migrations under Hitler

    Science.gov (United States)

    Beyerchen, Alan

    2011-03-01

    When the Nazis came to power in early 1933 they initiated formal and informal measures that forced Jews and political opponents from public institutions such as universities. Some physicists retired and others went into industry, but most emigrated. International communication and contact made emigration a viable option despite the desperate economic times in the Great Depression. Another wave of emigrations followed the annexation of Austria in 1938. Individual cases as well as general patterns of migration and adaptation to new environments will be examined in this presentation. One important result of the forced migrations was that many of the physicists expelled under Hitler played important roles in strengthening physics elsewhere, often on the Allied side in World War II.

  13. Clinically related anatomy for physicists

    International Nuclear Information System (INIS)

    Wright, A.E.; Boyer, A.L.

    1987-01-01

    With the advent of CT and MR imaging, delineation of malignancies and the shaping of radiation treatment fields have become much more precise. Treatment planning in more than one transverse plane is more widely practiced as the use of sophisticated computers grow. These developments emphasize the need for the physicist to have a basic knowledge of human anatomy. This course is designed to familiarize the clinical physicist with the gross anatomy and topographic landmarks used by the physician in planning three-dimensional radiation treatment volumes. The significance of the various anatomic structures and their related lymphatics in the spread of disease is discussed. Emphasis is placed on disease entities that pose particular problems due to overlying or nearby healthy structures at risk

  14. Friction Pull Plug and Material Configuration for Anti-Chatter Friction Pull Plug Weld

    Science.gov (United States)

    Littell, Justin Anderson (Inventor)

    2016-01-01

    A friction pull plug is provided for use in forming a plug weld in a hole in a material. The friction pull plug includes a shank and a series of three frustoconical sections. The relative sizes of the sections assure that a central one of the sections defines the initial contact point between the hole's sides. The angle defined by the central one of the sections reduces or eliminates chatter as the plug is pulled into the hole.

  15. Relay chatter and operator response after a large earthquake: An improved PRA methodology with case studies

    International Nuclear Information System (INIS)

    Budnitz, R.J.; Lambert, H.E.; Hill, E.E.

    1987-08-01

    The purpose of this project has been to develop and demonstrate improvements in the PRA methodology used for analyzing earthquake-induced accidents at nuclear power reactors. Specifically, the project addresses methodological weaknesses in the PRA systems analysis used for studying post-earthquake relay chatter and for quantifying human response under high stress. An improved PRA methodology for relay-chatter analysis is developed, and its use is demonstrated through analysis of the Zion-1 and LaSalle-2 reactors as case studies. This demonstration analysis is intended to show that the methodology can be applied in actual cases, and the numerical values of core-damage frequency are not realistic. The analysis relies on SSMRP-based methodologies and data bases. For both Zion-1 and LaSalle-2, assuming that loss of offsite power (LOSP) occurs after a large earthquake and that there are no operator recovery actions, the analysis finds very many combinations (Boolean minimal cut sets) involving chatter of three or four relays and/or pressure switch contacts. The analysis finds that the number of min-cut-set combinations is so large that there is a very high likelihood (of the order of unity) that at least one combination will occur after earthquake-caused LOSP. This conclusion depends in detail on the fragility curves and response assumptions used for chatter. Core-damage frequencies are calculated, but they are probably pessimistic because assuming zero credit for operator recovery is pessimistic. The project has also developed an improved PRA methodology for quantifying operator error under high-stress conditions such as after a large earthquake. Single-operator and multiple-operator error rates are developed, and a case study involving an 8-step procedure (establishing feed-and-bleed in a PWR after an earthquake-initiated accident) is used to demonstrate the methodology

  16. Eddy currents self-tuning dynamic vibration absorber for machine tool chatter suppression

    OpenAIRE

    Aguirre , Gorka; Gorostiaga , Mikel; Porchez , Thomas; Munoa , Jokin

    2013-01-01

    International audience; The current trend in machine tool design aims at stiffer machines with lowerinfluence of friction, leading to faster and more precise machines. However, this is atthe expense of reducing the machine damping, which is mainly produced by friction,and thus increasing the risk of suffering from a self-excited vibration named chatter,which limits the productivity of the process. Dynamic vibration absorbers (DVAs)offer a relatively simple and low cost solution to reduce chat...

  17. Chattering-Free Adaptive Sliding Mode Control for Attitude Tracking of Spacecraft with External Disturbance

    Directory of Open Access Journals (Sweden)

    Xuxi Zhang

    2014-01-01

    Full Text Available The attitude tracking problem of spacecraft in the presence of unknown disturbance is investigated. By using the adaptive control technique and the Lyapunov stability theory, a chattering-free adaptive sliding mode control law is proposed for the attitude tracking problem of spacecraft with unknown disturbance. Simulation results are employed to demonstrate the effectiveness of the proposed control design technique in this paper.

  18. EPS Young Physicist Prize - CORRECTION

    CERN Multimedia

    2009-01-01

    The original text for the article 'Prizes aplenty in Krakow' in Bulletin 30-31 assigned the award of the EPS HEPP Young Physicist Prize to Maurizio Pierini. In fact he shared the prize with Niki Saoulidou of Fermilab, who was rewarded for her contribution to neutrino physics, as the article now correctly indicates. We apologise for not having named Niki Saoulidou in the original article.

  19. Physicist makes muon chamber sing

    CERN Multimedia

    2007-01-01

    This Monitored Drift Tube detector, consisting of argon-CO2-filled aluminium tubes with a wire down the centre of each, will track muons in ATLAS; Tiecke used a single tube from one of these detectors to create the pipes in his organ. Particle physicists can make good musicians; but did you know particle detectors can make good music? That's what NIKHEF physicist Henk Tiecke learned when he used pipes cut from the ATLAS Monitored Drift Tube detector (MDT) to build his own working Dutch-style barrel organ in the autumn of 2005. 'I like to work with my hands,' said Tiecke, who worked as a senior physicist at NIKHEF, Amsterdam, on ZEUS until his retirement last summer. Tiecke had already constructed his barrel organ when he visited some colleagues in the ATLAS muon chambers production area at Nikhef in 2005. He noticed that the aluminium tubes they were using to build the chambers were about three centimetres in diameter-just the right size for a pipe in a barrel organ. 'The sound is not as nice as from wooden...

  20. Chatter reduction in boring process by using piezoelectric shunt damping with experimental verification

    Science.gov (United States)

    Yigit, Ufuk; Cigeroglu, Ender; Budak, Erhan

    2017-09-01

    Chatter is a self-excited type of vibration that develops during machining due to process-structure dynamic interactions resulting in modulated chip thickness. Chatter is an important problem as it results in poor surface quality, reduced productivity and tool life. The stability of a cutting process is strongly influenced by the frequency response function (FRF) at the cutting point. In this study, the effect of piezoelectric shunt damping on chatter vibrations in a boring process is studied. In piezoelectric shunt damping method, an electrical impedance is connected to a piezoelectric transducer which is bonded on cutting tool. Electrical impedance of the circuit consisting of piezoceramic transducer and passive shunt is tuned to the desired natural frequency of the cutting tool in order to maximize damping. The optimum damping is achieved in analytical and finite element models (FEM) by using a genetic algorithm focusing on the real part of the tool point FRF rather than the amplitude. Later, a practical boring bar is considered where the optimum circuit parameters are obtained by the FEM. Afterwards, the effect of the optimized piezoelectric shunt damping on the dynamic rigidity and absolute stability limit of the cutting process are investigated experimentally by modal analysis and cutting tests. It is both theoretically and experimentally shown that application of piezoelectric shunt damping results in a significant increase in the absolute stability limit in boring operations.

  1. My recollections as a physicist

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, Yung-su

    1997-03-01

    This presentation is a talk presented by the author at a Physics Symposium of the 50th anniversary of the Taiwan University, in December 1996. The author describes how he became a physicist, and then presents a brief outline of his professional career, most of which has centered at Stanford Linear Accelerator Center. He was involved in the discovery of the {tau} lepton, and in studies of CP violation through decay of the {tau}, in addition to studies of semileptonic decay of t, B, D, K, and {pi}.

  2. Murdered physicist leaves Iran reeling

    Science.gov (United States)

    Dacey, James

    2010-02-01

    The murder of the Iranian physicist Masoud Alimohammadi last month has left the country's academic community in a state of shock. Alimohammadi, a 50-year-old physics professor at the University of Tehran, was killed on 12 January by a remote-controlled bomb attached to the side of a motorcycle outside his home. The bomb was detonated as he left for work, but the reason for the murder remained unclear as Physics World went to press. Reports by the Iranian state media blamed the US and Israel for the attack - a claim that the US later described as "absurd".

  3. An Applied Physicist Does Econometrics

    Science.gov (United States)

    Taff, L. G.

    2010-02-01

    The biggest problem those attempting to understand econometric data, via modeling, have is that economics has no F = ma. Without a theoretical underpinning, econometricians have no way to build a good model to fit observations to. Physicists do, and when F = ma failed, we knew it. Still desiring to comprehend econometric data, applied economists turn to mis-applying probability theory---especially with regard to the assumptions concerning random errors---and choosing extremely simplistic analytical formulations of inter-relationships. This introduces model bias to an unknown degree. An applied physicist, used to having to match observations to a numerical or analytical model with a firm theoretical basis, modify the model, re-perform the analysis, and then know why, and when, to delete ``outliers'', is at a considerable advantage when quantitatively analyzing econometric data. I treat two cases. One is to determine the household density distribution of total assets, annual income, age, level of education, race, and marital status. Each of these ``independent'' variables is highly correlated with every other but only current annual income and level of education follow a linear relationship. The other is to discover the functional dependence of total assets on the distribution of assets: total assets has an amazingly tight power law dependence on a quadratic function of portfolio composition. Who knew? )

  4. The impact of seismically-induced relay chatter on nuclear plant risk

    International Nuclear Information System (INIS)

    Bley, D.C.; McIntyre, T.J.; Smith, B.; Kassawara, R.P.

    1987-01-01

    This paper describes a systematic scheme for analyzing the impact of relay chatter that is amenable to both PRA analysis and seismic margins analysis. It uses knowledge of the systems engineering of the plant to bound the scope of the problem to a tractable size and has been applied to both the Diablo Canyon PRA and the EPRI seismic margines program trial evaluation at the Catawba Nuclear Power Plant. It has also been coordinated with similar EPRI-sponsored work on relay functionality for the Seismic Qualification Utility Group. (orig./HP)

  5. Chattering-free sliding mode observer for speed sensorless control of PMSM

    Directory of Open Access Journals (Sweden)

    Mahmoud M. Gaballah

    2017-07-01

    Full Text Available This article presents a new speed observer based on fuzzy logic for speed sensorless control applications of permanent magnet synchronous motor “PMSM”. The switch function in traditional Sliding Mode Observer “SMO” is replaced by a rule based fuzzy logic system. The proposed observer not only improves the system dynamic performance during disturbances or parameter variations, but also has a high accuracy tracking performance with sufficient chattering reduction. The validity of the new observer corroborated through experimental results using TMS320F28069M Digital Signal Processor “DSP”.

  6. Britain honours its particle physicists

    CERN Multimedia

    2004-01-01

    Theoretical and experimental particle physicists figure among the winners for 2004 of Britain's most prestigious prizes for physics, awarded by the Institute of Physics (IOP). The IOP's own Paul Dirac medal and prize, goes to this year to CERN's John Ellis for "his highly influential work on particle-physics phenomenology; in particular on the properties of gluons, the Higgs boson and the top quark". One of the institute's premier wards, it is made for outstanding contributions to theoretical (including mathematical and computational) physics. The Duddell medal and prize, in memory of William du Bois Duddell, the inventor of the electromagnetic oscillograph, is awarded for outstanding contributions to the advancement of knowledge through the application of physics, including the invention or design of scientific instruments or the discovery of materials used in their construction. It is shared this year by Geoff Hall, of Imperial College London, Alessandro Marchioro from CERN and Peter Sharp of the Rutherfor...

  7. Tales of physicists and mathematicians

    CERN Document Server

    Gindikin, Semyon Grigorevich

    1988-01-01

    This revised and greatly expanded second edition of the classic Russian text Tales of Mathematicians and Physicists contains a wealth of new information about the lives and accomplishments of more than a dozen scientists throughout history. Included are individuals from the late nineteenth century: Klein, Poincaré, Ramanujan, and Penrose, as well as renowned figures from earlier eras, such as Leibniz, Euler, Lagrange, and Laplace. A unique mixture of mathematics, physics, and history, this volume provides biographical glimpses of scientists and their contributions in the context of the social and political background of their times. The author examines many original sources, from the scientists’ research papers to their personal documents and letters to friends and family; furthermore, detailed mathematical arguments and diagrams are supplied to help explain some of the most significant discoveries in calculus, celestial mechanics, number theory, and modern relativity. What emerges are intriguing, multifac...

  8. Radiation physics for medical physicists

    CERN Document Server

    Podgorsak, Ervin B

    2006-01-01

    This book summarizes the radiation physics knowledge that professionals working in medical physics need to master for efficient and safe dealings with ionizing radiation. It contains eight chapters, each chapter covering a specific group of subjects related to radiation physics and is intended as a textbook for a course in radiation physics in medical-physics graduate programs. However, the book may also be of interest to the large number of professionals, not only medical physicists, who in their daily occupations deal with various aspects of medical physics and find a need to improve their understanding of radiation physics. The main target audience for this book is graduate students studying for M.Sc. and Ph.D. degrees in medical physics, who have to possess the necessary physics and mathematics background knowledge to be able to follow and master the complete textbook. Medical residents, technology students and biomedical engineering students may find certain sections too challenging or esoteric, yet they...

  9. CERN physicist receives Einstein Medal

    CERN Multimedia

    2006-01-01

    On 29 June the CERN theorist Gabriele Veneziano was awarded the prestigious Albert Einstein Medal for significant contributions to the understanding of string theory. This award is given by the Albert Einstein Society in Bern to individuals whose scientific contributions relate to the work of Einstein. Former recipients include exceptional physicists such as Murray Gell-Mann last year, but also Stephen Hawking and Victor Weisskopf. Gabriele Veneziano, a member of the integrated CERN Theory Team since 1977, led the Theory Division from 1994 to 1997 and has already received many prestigious prizes for his outstanding work, including the Enrico Fermi Prize (see CERN Courier, November 2005), the Dannie Heineman Prize for mathematical physics of the American Physical Society in 2004 (see Bulletin No. 47/2003), and the I. Ya. Pomeranchuk Prize of the Institute of Theoretical and Experimental Physics (Moscow) in 1999.

  10. The Western Primary School 'Quiet Room' Project.

    Science.gov (United States)

    King, Angus; Chantler, Zara

    2002-01-01

    This article describes a "Quiet Room" project for students with social, emotional, and behavioral problems at a British primary school. The Quiet Room was designed to provide a nurturing environment away from the classroom in which a child's emotional needs can be explored on a one-to-one basis. Benefits for children, parents, and…

  11. Preventing chatter vibrations in heavy-duty turning operations in large horizontal lathes

    Science.gov (United States)

    Urbikain, G.; Campa, F.-J.; Zulaika, J.-J.; López de Lacalle, L.-N.; Alonso, M.-A.; Collado, V.

    2015-03-01

    Productivity and surface finish are typical user manufacturer requirements that are restrained by chatter vibrations sooner or later in every machining operation. Thus, manufacturers are interested in knowing, before building the machine, the dynamic behaviour of each machine structure with respect to another. Stability lobe graphs are the most reliable approach to analyse the dynamic performance. During heavy rough turning operations a model containing (a) several modes, or (b) modes with non-conventional (Cartesian) orientations is necessary. This work proposes two methods which are combined with multimode analysis to predict chatter in big horizontal lathes. First, a traditional single frequency model (SFM) is used. Secondly, the modern collocation method based on the Chebyshev polynomials (CCM) is alternatively studied. The models can be used to identify the machine design features limiting lathe productivity, as well as the threshold values for choosing good cutting parameters. The results have been compared with experimental tests in a horizontal turning centre. Besides the model and approach, this work offers real worthy values for big lathes, difficult to be got from literature.

  12. Chattering-Free Neuro-Sliding Mode Control of 2-DOF Planar Parallel Manipulators

    Directory of Open Access Journals (Sweden)

    Tien Dung Le

    2013-01-01

    Full Text Available This paper proposes a novel chattering free neuro-sliding mode controller for the trajectory tracking control of two degrees of freedom (DOF parallel manipulators which have a complicated dynamic model, including modelling uncertainties, frictional uncertainties and external disturbances. A feedforward neural network (NN is combined with an error estimator to completely compensate the large nonlinear uncertainties and external disturbances of the parallel manipulators. The online weight tuning algorithms of the NN and the structure of the error estimator are derived with the strict theoretical stability proof of the Lyapunov theorem. The upper bound of uncertainties and the upper bound of the approximation errors are not required to be known in advance in order to guarantee the stability of the closed-loop system. The example simulation results show the effectiveness of the proposed control strategy for the tracking control of a 2-DOF parallel manipulator. It results in its being chattering-free, very small tracking errors and its robustness against uncertainties and external disturbances.

  13. The impact of relay chatter on the availability of plant systems following a seismic event

    International Nuclear Information System (INIS)

    Evans, M.G.K.; Su, Y.J.

    1985-01-01

    In performing a risk analysis of a nuclear power plant, one of the most important factors in determining the availability of those systems required to safely shut down the plant is the impact of common cause failures resulting from such events as fire, flooding or earthquakes. In the latter case it is particularly important to do a thorough analysis of the effects of the earthquake for plants built in zones of high seismicity such as the western United States, Japan or Taiwan. Much work has been done on the susceptibility of components to gross failure but little on the possibilities of relay chatter leading to the unavailability of many systems as the result of lock out of pumps or the changed status of valves. In this paper the authors look at the potential for electrical breaker failure and found that it is possible for a significant number of breakers supplying emergency pumps to be locked out following earthquakes such that the only other failure may well have been a loss of offsite power due to failure of switchyard insulators. They also identified the potential for individual valve operation within a system as the result of relay chatter, and the impact on the overall system availability. Finally they show how this can be incorporated into the quantification of the overall impact of the earthquake

  14. Physicist pins hopes on particle collider

    CERN Multimedia

    2007-01-01

    Physicist pins hopes on particle collider By Deseret Morning News Published: Monday, Dec. 31, 27 12:4 a.m. MST FONT Scott Thomas, a 187 State University graduate, is working at the frontiers of science. The theoretical physicist is crafting ways to extract fundamental secrets that seem certain to be uncovered by the Large Hadron Collider.

  15. Marie Curie: Physicist and Woman

    Science.gov (United States)

    Howes, Ruth

    Marie Sklodowska was born in Warsaw on November 7, 1867. Girls were not allowed to attend college in Poland, so Marie found a well-paying post as a governess in rural village which she held for three years while helping her older sister complete medical school in Paris. Then Marie moved to Paris and graduated first in her class at the Sorbonne with a master's degree in physics in 1893. In 1895, she married the talented young physicist, Pierre Curie. Marie decided to investigate the radioactive components of the mineral pitchblende for her dissertation. The work involved chemical analysis of a ton of material in an unheated shed. Pierre joined her and at the end of 1898, the Curies announced the discovery of radium and polonium. Through 1899, Marie labored to measure the atomic weight of radium. In 1903, Marie earned her doctorate, the first for a woman in France, and the Curies split the Nobel Prize in Physics with Henri Becquerel. They became widely known, besieged by the press and frequently invited to make presentations and be awarded honors. They hated fame and both suffered bad health. In April, 1906, Pierre Curie was struck by a wagon and killed instantly. Marie was left as a single mother with two young daughters. Fortunately, the Sorbonne hired her to fill Pierre's position. In 1911, she was rejected for membership in the French Academy of Science because she was a woman. Also in 1911, she was accused of having an affair with a married French physicist Paul Langevin. The resulting scandal hit the press and brought angry mobs to her home. In the middle of this hullaballoo, she was informed that she had won a second Nobel Prize, this time in Chemistry. When World War I broke out, Marie mounted x-ray units on cars and became a heroine. She visited the United States in 1921 where President Harding presented her with a gram of radium. She continued her scientific studies in spite of declining health until her death in 1934. Professor Emerita.

  16. Deutsch, Doyc or Doitsch? Chatters as Languagers--The Case of a German-Turkish Chat Room

    Science.gov (United States)

    Hinnenkamp, Volker

    2008-01-01

    The paper looks at the process of online-languaging of adolescents with a migratory and ethnic Turkish background in a diasporic chat room. The multiple resources and voices used are analysed. One particular example is looked at more thoroughly to illustrate the process of languaging and how it is legitimised by the chatters themselves. Finally,…

  17. ROLE OF DISCRETE NATURE OF CHIP FORMATION AND NATURAL VIBRATIONS OF SYSTEM COMPONENTS IN CHATTER FORMATION DURING METAL CUTTING

    Directory of Open Access Journals (Sweden)

    A. K. M. Nurulamin

    2010-05-01

    Full Text Available In the present work a review of the existing theories of chatter formation has been conducted and the weaknesses of the most widely accepted ‘Regenerative Chatter theory’ in explaining various phenomena related to chatter formation have been identified. An attempt has been made in this work to determine the common causes of chatter formation in different metal cutting operations, namely, turning, thread cutting and end milling conducted on plain carbon steel AISI 1040. Experimental investigations have been conducted during the above types of machining processes to identify the marks of instability and chatter on the formed chips. It has been identified that in all the three machining operations the chips formed show a common type of discreteness in the form of secondary saw teeth, which appear at the free edge of the chip. Mechanism of formation of these teeth has been studied and the frequencies of their formation have been determined for different cutting conditions. Apart from the secondary saw teeth primary saw teeth have also been identified at the main section of the chip and their frequencies were also determined. At the same time the natural vibrations of the main system components have been identified and the acceleration amplitudes at the prominent natural frequencies during actual machining were recoded using a dedicated vibration monitoring system. The frequencies of secondary chip serration and the natural frequencies of the system components were plotted against cutting speed. Acceleration amplitudes at the prominent natural frequencies were also plotted separately against cutting force. Based on comparison and analysis of these two frequency and amplitude graphs it was concluded that chatter (vibration with relatively high amplitude appears in the system when the frequency of secondary saw teeth approaches values equal to half or integer multiple of a prominent natural frequency of the system resulting in resonance. In the

  18. Radiation physics for medical physicists

    International Nuclear Information System (INIS)

    Podgorsak, E.B.

    2006-01-01

    This book summarizes the radiation physics knowledge that professionals working in medical physics need to master for efficient and safe dealings with ionizing radiation. It contains eight chapters, each chapter covering a specific group of subjects related to radiation physics and is intended as a textbook for a course in radiation physics in medical-physics graduate programs. However, the book may also be of interest to the large number of professionals, not only medical physicists, who in their daily occupations deal with various aspects of medical physics and find a need to improve their understanding of radiation physics. The main target audience for this book is graduate students studying for M.Sc. and Ph.D. degrees in medical physics, who have to possess the necessary physics and mathematics background knowledge to be able to follow and master the complete textbook. Medical residents, technology students and biomedical engineering students may find certain sections too challenging or esoteric, yet they will find many sections interesting and useful in their studies. Candidates preparing for professional certification exams in any of the medical physics subspecialties should find the material useful, and some of the material would also help candidates preparing for certification examinations in medical dosimetry or radiation-related medical specialties. Numerous textbooks are available covering the various subspecialties of medical physics but they generally make a transition from the elementary basic physics directly into the intricacies of the given medical physics subspecialty. The intent of this textbook is to provide the missing link between the elementary physics on the one hand and the physics of the subspecialties on the other hand. (orig.)

  19. Developing Technology Products - A Physicist's Perspective

    Science.gov (United States)

    Burka, Michael

    2014-03-01

    There are many physicists working in the industrial sector. We rarely have the word physicist in our job title; we are far more commonly called engineers or scientists. But, we are physicists, and we succeed because our training in physics has given us the habits of mind and the technical skills that one needs to solve complex technical challenges. This talk will explore the transition from physics research to technology product development using examples from my own career, first as a postdoctoral fellow and research scientist on the LIGO project, and then developing products in the spectroscopy, telecommunications, and medical device industries. Approaches to identifying and pursuing opportunities in industry will be discussed.

  20. A Discrete-Time Chattering Free Sliding Mode Control with Multirate Sampling Method for Flight Simulator

    Directory of Open Access Journals (Sweden)

    Yunjie Wu

    2013-01-01

    Full Text Available In order to improve the tracking accuracy of flight simulator and expend its frequency response, a multirate-sampling-method-based discrete-time chattering free sliding mode control is developed and imported into the systems. By constructing the multirate sampling sliding mode controller, the flight simulator can perfectly track a given reference signal with an arbitrarily small dynamic tracking error, and the problems caused by a contradiction of reference signal period and control period in traditional design method can be eliminated. It is proved by theoretical analysis that the extremely high dynamic tracking precision can be obtained. Meanwhile, the robustness is guaranteed by sliding mode control even though there are modeling mismatch, external disturbances and measure noise. The validity of the proposed method is confirmed by experiments on flight simulator.

  1. Physicists observe subatomic quick-change artist

    CERN Multimedia

    Halber, Deborah

    2006-01-01

    Physicists have announced the observation of a subatomic particle known as the Bs (pronounced "B sub s") meson switching between matter and antimatter states at a mind-boggling 3 trillion times per second (1 page)

  2. More Sci- than Fi, Physicists Create Antimatter

    CERN Multimedia

    Overbye, Dennis

    2002-01-01

    Physicists working in Europe announced yesterday that they had passed through nature's looking glass and had created atoms made of antimatter, or antiatoms, opening up the possibility of experiments in a realm once reserved for science fiction writers (5 pages)

  3. Physicist swaps protons for profit strategies

    CERN Document Server

    Starck, Peter

    2006-01-01

    "A german particle physicist has decided to try his hand as a hedge fund manager and is confident that his award-winning algorithm will mean he hits his return target within weeks of launch." (1/2 page)

  4. Porcine lens nuclei as a model for comparison of 3 ultrasound modalities regarding efficiency and chatter.

    Science.gov (United States)

    Oakey, Zack B; Jensen, Jason D; Zaugg, Brian E; Radmall, Bryce R; Pettey, Jeff H; Olson, Randall J

    2013-08-01

    To validate a porcine lens model by comparing density and ultrasound (US) with known human standards using the Infiniti Ozil with Intelligent Phacoemulsification (torsional), Whitestar Signature Micropulse (longitudinal), and Ellips FX (transversal) modalities. Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Experimental study. Lens nuclei were formalin soaked in hour-based intervals and divided into 2.0 mm cubes. Density was characterized by crushing experiments and compared with known human measures. Efficiency and chatter were examined. The mean weight to cut thickness in half ranged from 16.9 g ± 5.5 (SD) in the 0-hour group to 121.3 ± 47.5 gm in the 4-hour group. Lenses in the 2-hour group (mean 70.2 ± 19.1 g) best matched human density (P=.215). The mean efficiency ranged from 0.432 ± 0.178 seconds to 9.111 ± 2.925 seconds; chatter ranged from zero to 1.85 ± 1.927 bounces. No significant difference was detected when comparing the 2-hour formalin group with human lenses in torsional and transversal US. There was no significant difference between transversal and torsional modalities, consistent with human studies. Although longitudinal (6 milliseconds on, 12 milliseconds off) was significantly more efficient at 50% power than at 25%, there was no significant difference compared with transversal or torsional US. Animal lenses soaked for 2 hours in formalin were most comparable to human lenses. Longitudinal US may be an acceptable alternative to torsional and transversal US. Copyright © 2013 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  5. Prediction of dynamic cutting force and regenerative chatter stability in inserted cutters milling

    Science.gov (United States)

    Li, Zhongqun; Liu, Qiang; Yuan, Songmei; Huang, Kaisheng

    2013-05-01

    Currently, the modeling of cutting process mainly focuses on two aspects: one is the setup of the universal cutting force model that can be adapted to a broader cutting condition; the other is the setup of the exact cutting force model that can accurately reflect a true cutting process. However, there is little research on the prediction of chatter stablity in milling. Based on the generalized mathematical model of inserted cutters introduced by ENGIN, an improved geometrical, mechanical and dynamic model for the vast variety of inserted cutters widely used in engineering applications is presented, in which the average directional cutting force coefficients are obtained by means of a numerical approach, thus leading to an analytical determination of stability lobes diagram (SLD) on the axial depth of cut. A new kind of SLD on the radial depth of cut is also created to satisfy the special requirement of inserted cutter milling. The corresponding algorithms used for predicting cutting forces, vibrations, dimensional surface finish and stability lobes in inserted cutter milling under different cutting conditions are put forward. Thereafter, a dynamic simulation module of inserted cutter milling is implemented by using hybrid program of Matlab with Visual Basic. Verification tests are conducted on a vertical machine center for Aluminum alloy LC4 by using two different types of inserted cutters, and the effectiveness of the model and the algorithm is verified by the good agreement of simulation result with that of cutting tests under different cutting conditions. The proposed model can predict the cutting process accurately under a variety of cutting conditions, and a high efficient and chatter-free milling operation can be achieved by a cutting condition optimization in industry applications.

  6. Meeting "real" physicists in the flesh

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    CERN physicists don't wear white coats (at least not very often); they don't all wear glasses and they don't concoct dangerous potions. They are often even women. These are some of the discoveries made by children from local schools taking part in the "Draw me a physicist" project. Franck Martin, an ATLAS physicist, answers questions from children from the Satigny-Village school.   20 school-classes from the Swiss communes of Meyrin, Satigny and Vernier and from the Pays de Gex in France have been taking part in this project, which involved the children making an initial drawing and writing a "dictionary-style" definition of a physicist in their classrooms, and then visiting CERN during the week of March 15th. The Swiss children were also treated to a show put on by the Physicscope group. During their visit to CERN they were able to see the laboratories and experiments for real and get an idea of what a physicist's job involves by interviewing a real male and...

  7. The "Roar of Chatter" in the Library at San Joaquin Delta College. Research Project.

    Science.gov (United States)

    Evans, Richard B.

    Quiet signs and verbal cautioning by library staff do not decrease library noise levels as revealed by two tests using sound measuring equipment at San Joaquin Delta College. The levels in fact increased, confirming previous opinions that signs and staff intervention have little effect on patron behavior. Test methods, data, and five references…

  8. Delay differential equations via the matrix Lambert W function and bifurcation analysis: application to machine tool chatter.

    Science.gov (United States)

    Yi, Sun; Nelson, Patrick W; Ulsoy, A Galip

    2007-04-01

    In a turning process modeled using delay differential equations (DDEs), we investigate the stability of the regenerative machine tool chatter problem. An approach using the matrix Lambert W function for the analytical solution to systems of delay differential equations is applied to this problem and compared with the result obtained using a bifurcation analysis. The Lambert W function, known to be useful for solving scalar first-order DDEs, has recently been extended to a matrix Lambert W function approach to solve systems of DDEs. The essential advantages of the matrix Lambert W approach are not only the similarity to the concept of the state transition matrix in lin ear ordinary differential equations, enabling its use for general classes of linear delay differential equations, but also the observation that we need only the principal branch among an infinite number of roots to determine the stability of a system of DDEs. The bifurcation method combined with Sturm sequences provides an algorithm for determining the stability of DDEs without restrictive geometric analysis. With this approach, one can obtain the critical values of delay, which determine the stability of a system and hence the preferred operating spindle speed without chatter. We apply both the matrix Lambert W function and the bifurcation analysis approach to the problem of chatter stability in turning, and compare the results obtained to existing methods. The two new approaches show excellent accuracy and certain other advantages, when compared to traditional graphical, computational and approximate methods.

  9. 76 FR 64353 - Buy Quiet Workshop

    Science.gov (United States)

    2011-10-18

    ... no later than October 21, 2011: 1. Name: 2. Gender: 3. Date of Birth: 4. Place of birth (city, province, state, country): 5. Citizenship: 6. Passport Number: 7. Date of Passport Issue: 8. Date of... employee representatives who want to assist in bringing ``Buy Quiet'' programs into the workplace. Format...

  10. Quiet engine program flight engine design study

    Science.gov (United States)

    Klapproth, J. F.; Neitzel, R. E.; Seeley, C. T.

    1974-01-01

    The results are presented of a preliminary flight engine design study based on the Quiet Engine Program high-bypass, low-noise turbofan engines. Engine configurations, weight, noise characteristics, and performance over a range of flight conditions typical of a subsonic transport aircraft were considered. High and low tip speed engines in various acoustically treated nacelle configurations were included.

  11. Particle physicists want to expand open access

    CERN Multimedia

    Kaiser, Jocelyn

    2006-01-01

    "Particle physicists have come up with a novel way to promote free, immediate access to journal articles. Led by CERN, the gian lab near Geneva, Switzerland, they want to raise at least $6 million a year to begin buying open access to all published papers in their field." (1 page)

  12. Physicists tackles questions of tiny dimensions

    CERN Multimedia

    Moran, Barbara

    2003-01-01

    Today's physicists have a dilemna: they are using two separate theories to describe the universe. General relativity, which describes gravity, works for large objects like planets. Quantum mechanics, which involves the other forces, works for tiny objects like atoms. Unfortunately, the two theories don't match up.

  13. Particle physicists join battle against cancer

    CERN Multimedia

    Cartlidge, Edwin

    2005-01-01

    Technologies originally developed for experiments in particle physcis are being used to diagnose and treat cancer. About 130 physicists and healthcare proessionals met in London recently to discuss "The future of medical imaging and radiotherapy"; a major theme at the meeting was how technology from particle physics could be used to diagnose and treat cancer (1/2 page)

  14. Introductory fluid mechanics for physicists and mathematicians

    CERN Document Server

    Pert, Geoffrey J

    2013-01-01

    This textbook presents essential methodology for physicists of the theory and applications of fluid mechanics within a single volume.  Building steadily through a syllabus, it will be relevant to almost all undergraduate physics degrees which include an option on hydrodynamics, or a course in which hydrodynamics figures prominently.

  15. SLAC physicists develop test for string theory

    CERN Multimedia

    Yajnik, Juhi

    2006-01-01

    "Under certain conditions, string theory solves many of the questions wracking the minds of physicists, but until recently it had one major flaw - it could not be tested. SLAC (Stanford Linear Accelerator Center) scientists have found a way to test this revolutionary theory, which posits that there are 10 or 11 dimensions in our universe" (1 page)

  16. Particle physicists want to expand open access

    CERN Multimedia

    Kaiser, Jocelyn

    2006-01-01

    "Particle physicists have come up with a novel way to promote free, immediate access to journal articles. Led by CERN, the giant lab near Geneva, Switzerland, thay want to raise at lesat $6 million a year to begin buying open access to all published papers in their field." (1/2 page)

  17. Physicist challenges prevailing view of math

    CERN Multimedia

    Burton, H

    2004-01-01

    Article about Michael Berry, a renowned mathematical physicist from the University of Bristol in England. Rather than trying to discover profound mathematical relationships in the physical world, Prof. Berry looks to the real world for "applications" of mathematical relationships (1 page)

  18. Physics Climate as Experienced by LGBT+ Physicists

    Science.gov (United States)

    Long, Elena

    2012-02-01

    In 2009, Elena Long created the LGBT+ Physicists website (http://lgbtphysicists.x10hosting.com) as a warehouse for resources useful for sexual and gender minorities working in physics. This resource has grown to include networking resources, lists of LGBT-friendly universities and localities, recommendations for enacting positive change in physics communities, and out-reach to other STEM-oriented LGBT organizations. This has been possible in large part by the dynamic community of LGBT+ physicists and allies looking to make physics more welcoming towards our community. In 2011, Elena used hir position as Member at Large on the executive committee of the Forum of Graduate Student Affairs (FGSA) to conduct a climate survey that included, among other things, the first serious look at LGBT+ demographics in physics. The survey focused particularly on issues of language heard and harassment experienced by physicists and was broken down into categories based on race, physical and mental ability, gender, and sexuality. Furthermore, it examined the outcomes of experienced harassment and the reasons for when harassment was not reported. Due to the nature of the study, overlapping demographics, especially ``multiple minorities,'' were also explored. This talk will give a brief history of the LGBT+ Physicists resource as well as an overview of the FGSA study.

  19. Directory and survey of particle physicists

    International Nuclear Information System (INIS)

    1997-04-01

    In order to develop a clearer understanding of the demographics of the U.S. particle physics workforce, the US Department of Energy, the National Science Foundation, and the Division of Particles and Fields of the American Physical Society commissioned a survey and census of particle physicists employed in the United States. This survey and census were conducted in 1995, with an update of the census in April 1997. The agencies and the scientific community were represented for the 1995 efforts by Dr. Robert Woods (DOE), Dr. William Chinowsky (NSF), and Prof. Uriel Nauenberg (DPF); for the current census, by Dr. Robert Diebold (DOE), Dr. Marvin Goldberg (NSF), and Dr. Patricia Rankin (NSF). The survey/census were carried out with the assistance of the Particle Data Group at Lawrence Berkeley National Laboratory. In order to obtain an accurate study of the current workforce and of future needs, we requested that all HEP physicists fill out and return the 1995 survey. There were 2494 respondents. For the 1997 census, a representative of each university and laboratory was asked to provide information on all persons at that institution who spend at least 50% of their research time on particle physics. In some cases this includes accelerator physicists. The total number of physicists in the 1997 census is 3492 from 155 institutions in the United States. The full survey questionnaires are shown. The primary one was addressed to individual particle physicists, while the secondary one was addressed to principal investigators and sought information about people leaving the field. There are many possible tables and plots from this survey, with a variety of correlations. Those chosen are representative of a cross-section of the demographic results. It should be emphasized that this survey was a snapshot in time, and does not have the same capabilities as would a series of surveys that are periodic in time. Care should be taken in interpreting the results of the tables and plots

  20. Directory and survey of particle physicists

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-04-01

    In order to develop a clearer understanding of the demographics of the U.S. particle physics workforce, the US Department of Energy, the National Science Foundation, and the Division of Particles and Fields of the American Physical Society commissioned a survey and census of particle physicists employed in the United States. This survey and census were conducted in 1995, with an update of the census in April 1997. The agencies and the scientific community were represented for the 1995 efforts by Dr. Robert Woods (DOE), Dr. William Chinowsky (NSF), and Prof. Uriel Nauenberg (DPF); for the current census, by Dr. Robert Diebold (DOE), Dr. Marvin Goldberg (NSF), and Dr. Patricia Rankin (NSF). The survey/census were carried out with the assistance of the Particle Data Group at Lawrence Berkeley National Laboratory. In order to obtain an accurate study of the current workforce and of future needs, we requested that all HEP physicists fill out and return the 1995 survey. There were 2494 respondents. For the 1997 census, a representative of each university and laboratory was asked to provide information on all persons at that institution who spend at least 50% of their research time on particle physics. In some cases this includes accelerator physicists. The total number of physicists in the 1997 census is 3492 from 155 institutions in the United States. The full survey questionnaires are shown. The primary one was addressed to individual particle physicists, while the secondary one was addressed to principal investigators and sought information about people leaving the field. There are many possible tables and plots from this survey, with a variety of correlations. Those chosen are representative of a cross-section of the demographic results. It should be emphasized that this survey was a snapshot in time, and does not have the same capabilities as would a series of surveys that are periodic in time. Care should be taken in interpreting the results of the tables and plots.

  1. Fermi: a physicist in the upheaval

    International Nuclear Information System (INIS)

    Maria, M. de

    2002-01-01

    This book summarizes the life, works and complex personality of the Italian physicist Enrico Fermi (1901-1954) whose myth is linked with the political upheaval of the 2. world war: the youth of an autodidact, the theorician and the quantum mechanics, his invention of a quantum statistics, the weak interaction theory, his works on artificial radioactivity, the end of the Fermi team and his exile in the USA, the secrete researches at the university of Columbia and the birth of the first atomic 'pile' (December 2, 1942), the building of Los Alamos center and the Alamogordo explosion test, the disagreements among the physicists of the Manhattan project and the position of Fermi, Fermi's contribution in the H-bomb construction, the creation of the physics school of Chicago, the Oppenheimer spying affair. (J.S.)

  2. The ethics of physicists in questions

    CERN Multimedia

    2000-01-01

    Four CERN physicists, Peggie Rimmer, Ugo Amaldi, Alain Blondel, and Jean-Marie Le Goff, answered questions from 150 college students last Monday during a debate on the theme of the ethics of physics. Organized by CERN and the Department of public instruction of the Canton of Geneva, the meeting followed a reading by the students of the play Die Physiker, by Friedrich Dürrenmatt, which raises the problem of political exploitation of discoveries made during the second world war. The Minister of Education of the Canton de Genève, Mrs Martine Brunschwig-Graf, took part in the debate. The questions posed by students were not lacking in pertinence : Should a physicist reveal a discovery that is dangerous in his opinion ? Who are responsible, those who make the discoveries or those who use them ?

  3. Radiation oncology a physicist's-eye view

    CERN Document Server

    Goitein, Michael

    2007-01-01

    Radiation Oncology: A Physicist's-Eye View was written for both physicists and medical oncologists with the aim of helping them approach the use of radiation in the treatment of cancer with understanding, confidence, and imagination. The book will let practitioners in one field understand the problems of, and find solutions for, practitioners in the other. It will help them to know "why" certain approaches are fruitful while, at the same time, encouraging them to ask the question "Why not?" in the face of assertions that some proposal of theirs is impractical, unreasonable, or impossible. Unlike a textbook, formal and complete developments of the topics are not among the goals. Instead, the reader will develop a foundation for understanding what the author has found to be matters of importance in radiation oncology during over thirty years of experience. Presentations cover, in largely non-technical language, the principal physical and biological aspects of radiation treatment and address practical clinical c...

  4. Development of the Future Physicists of Florida

    Science.gov (United States)

    Wade, A.; Weatherford, C.; Cottle, P.; Fannin, S.; Roberts, W.; Fauerbach, M.; Ponti, L.; Sear, J.

    2013-03-01

    We present the development of the ``Future Physicists of Florida'' (FPF) comprised of Florida university physics professors, middle and high school science teachers, and backed by the Florida Legislature. Our purpose is to address the lack of incoming college freshmen ready and willing to become physics majors. We will discuss the building of FPF and the development of a pipeline for middle and high school students predicted to produce the optimal number of bachelor's degrees in STEM. We will also discuss our use of community-building activities to educate the students, and their parents and teachers about the educational value of taking physics before going to college and potential careers in physics, to entertain them with fun physics related activities in order to peak their interest in physics, and to ultimately inspire the students to become physicists.

  5. The Status of Women Physicists in Pakistan

    Science.gov (United States)

    Hasnain, Aziz Fatima; Islam, Jabeen

    2009-04-01

    A significant number of women physicists work in high-ranking positions in the universities and research institutes of Pakistan; however, the number of women is much lower compared with men. We surveyed these women about the challenges they faced in the workplace and the pace of their progress and scientific work in a male-dominant society. We also surveyed girls' attitudes toward studying physics at the graduate and undergraduate levels.

  6. The Hidden Gifts of Quiet Kids

    Science.gov (United States)

    Trierweiler, Hannah

    2006-01-01

    The author relates that she was an introvert child. It has always taken her time and energy to find her place in a group. As a grown-up, she still needed quiet time to regroup during a busy day. In this article, the author presents an interview with Marti Olsen Laney, author of "The Hidden Gifts of the Introverted Child." During the interview,…

  7. Feedback between Accelerator Physicists and magnet builders

    International Nuclear Information System (INIS)

    Peggs, S.

    1995-01-01

    Our task is not to record history but to change it. (K. Marx (paraphrased)) How should Accelerator Physicists set magnet error specifications? In a crude social model, they place tolerance limits on undesirable nonlinearities and errors (higher order harmonics, component alignments, etc.). The Magnet Division then goes away for a suitably lengthy period of time, and comes back with a working magnet prototype that is reproduced in industry. A better solution is to set no specifications. Accelerator Physicists begin by evaluating expected values of harmonics, generated by the Magnet Division, before and during prototype construction. Damaging harmonics are traded off against innocuous harmonics as the prototype design evolves, lagging one generation behind the evolution of expected harmonics. Finally, the real harmonics are quickly evaluated during early industrial production, allowing a final round of performance trade-offs, using contingency scenarios prepared earlier. This solution assumes a close relationship and rapid feedback between the Accelerator Physicists and the magnet builders. What follows is one perspective of the way that rapid feedback was used to 'change history' (improve linear and dynamic aperture) at RHIC, to great benefit

  8. Small ripple shakes a roomful of physicists

    CERN Multimedia

    2011-01-01

    After the exciting results announced by CERN physicists at the EPS conference, the CERN Quantum Diaries blog gave an insightful recap of the news. Here's what blogger, Pauline Gagnon, reported...   The CMS collaboration combined results for the Higgs boson search covering a possible Higgs in the region from 110 to 600 GeV. This Friday afternoon, the 750 physicists attending the European Physics Society meeting in Grenoble, France, were pleasantly surprised. The audience was waiting with some anticipation to see the first important set of results from the two large LHC experiments, ATLAS and CMS on the search for the Higgs boson. In fact, for the past two days, results had been shown from both experiments as well as from the Tevatron experiments in various individual channels. But today, the latest combined results from each experiment were shown in public for the first time. Of course, all physicists belonging either to the CMS or ATLAS experiment had had a chance t...

  9. Radio-quiet Gamma-ray Pulsars

    Directory of Open Access Journals (Sweden)

    Lupin Chun-Che Lin

    2016-09-01

    Full Text Available A radio-quiet γ-ray pulsar is a neutron star that has significant γ-ray pulsation but without observed radio emission or only limited emission detected by high sensitivity radio surveys. The launch of the Fermi spacecraft in 2008 opened a new epoch to study the population of these pulsars. In the 2nd Fermi Large Area Telescope catalog of γ-ray pulsars, there are 35 (30 % of the 117 pulsars in the catalog known samples classified as radio-quiet γ-ray pulsars with radio flux density (S1400 of less than 30 μJy. Accompanying the observations obtained in various wavelengths, astronomers not only have the opportunity to study the emitting nature of radio-quiet γ-ray pulsars but also have proposed different models to explain their radiation mechanism. This article will review the history of the discovery, the emission properties, and the previous efforts to study pulsars in this population. Some particular cases known as Geminga-like pulsars (e.g., PSR J0633+1746, PSR J0007+7303, PSR J2021+4026, and so on are also to specified discuss their common and specific features.

  10. Brief, Embedded, Spontaneous Metacognitive Talk Indicates Thinking Like a Physicist

    Science.gov (United States)

    Sayre, Eleanor C.; Irving, Paul W.

    2015-01-01

    Instructors and researchers think "thinking like a physicist" is important for students' professional development. However, precise definitions and observational markers remain elusive. We reinterpret popular beliefs inventories in physics to indicate what physicists think thinking like a physicist entails. Through discourse analysis of…

  11. Mathematical methods for physicists a comprehensive guide

    CERN Document Server

    Arfken, George B; Harris, Frank E

    2012-01-01

    Now in its 7th edition, Mathematical Methods for Physicists continues to provide all the mathematical methods that aspiring scientists and engineers are likely to encounter as students and beginning researchers. This bestselling text provides mathematical relations and their proofs essential to the study of physics and related fields. While retaining the key features of the 6th edition, the new edition provides a more careful balance of explanation, theory, and examples. Taking a problem-solving-skills approach to incorporating theorems with applications, the book's improved focus w

  12. The Experiences of an Entrepreneurial Physicist

    Science.gov (United States)

    Kermani, Moe

    2012-10-01

    The majority of pre- and post-graduate training in physics is focused on the acquisition of hard skills necessary to pursue academic research within a specific discipline of the broader field. Often many physics graduates view a career transition from academia to the private sector with much consternation. In this presentation, Moe Kermani will share his experience in making the transition and discuss how elements of post graduate training in physics provide a good foundation for success as an entrepreneur. This presentation is primarily aimed at young physicists and graduate students that are considering a transition from the academic sector to the world of technology startups.

  13. Physicists make the most of antimatter

    International Nuclear Information System (INIS)

    Kalmus, Peter

    1987-01-01

    The paper concerns the detection and creation of antimatter. The concept of antimatter was first suggested by Schuster in 1898, was predicted by Dirac in the 1930's and discovered in an accelerator experiment in California in the 1950's. So far, physicists have found no evidence of large amounts of antimatter in nature. However, the creation of artificial antimatter in the laboratory is a possibility. The facilities at CERN should enable the making of antimatter, by using the antiproton beam from LEAR, to make antihydrogen. (UK)

  14. Heating the Chromosphere in the Quiet Sun

    Science.gov (United States)

    Kohler, Susanna

    2018-04-01

    The best-studied star the Sun still harbors mysteries for scientists to puzzle over. A new study has now explored the role of tiny magnetic-field hiccups in an effort to explain the strangely high temperatures of the Suns upper atmosphere.Schematic illustrating the temperatures in different layers of the Sun. [ESA]Strange Temperature RiseSince the Suns energy is produced in its core, the temperature is hottest here. As expected, the temperature decreases further from the Suns core up until just above its surface, where it oddly begins to rise again. While the Suns surface is 6,000 K, the temperature is higher above this: 10,000 K in the outer chromosphere.So how is the chromosphere of the Sun heated? Its possible that the explanation can be found not amid high solar activity, but in quiet-Sun regions.In a new study led by Milan Goi (Lockheed Martin Solar and Astrophysics Laboratory, Bay Area Environmental Research Institute), a team of scientists has examined a process that quietly happens in the background: the cancellation of magnetic field lines in the quiet Sun.Activity in a SupergranuleTop left: SDO AIA image of part of the solar disk. The next three panels are a zoom of the particular quiet-Sun region that the authors studied, all taken with IRIS at varying wavelengths: 1400 (top right), 2796 (bottom left), and 2832 (bottom right). [Goi et al. 2018]The Sun is threaded by strong magnetic field lines that divide it into supergranules measuring 30 million meters across (more than double the diameter of Earth!). Supergranules may seem quiet inside, but looks can be deceiving: the interiors of supergranules contain smaller, transient internetwork fields that move about, often resulting in magnetic elements of opposite polarity encountering and canceling each other.For those internetwork flux cancellations that occur above the Suns surface, a small amount of energy could be released that locally heats the chromosphere. But though each individual event has a small

  15. Design of Quiet Rotorcraft Approach Trajectories

    Science.gov (United States)

    Padula, Sharon L.; Burley, Casey L.; Boyd, D. Douglas, Jr.; Marcolini, Michael A.

    2009-01-01

    A optimization procedure for identifying quiet rotorcraft approach trajectories is proposed and demonstrated. The procedure employs a multi-objective genetic algorithm in order to reduce noise and create approach paths that will be acceptable to pilots and passengers. The concept is demonstrated by application to two different helicopters. The optimized paths are compared with one another and to a standard 6-deg approach path. The two demonstration cases validate the optimization procedure but highlight the need for improved noise prediction techniques and for additional rotorcraft acoustic data sets.

  16. Building 887: An Aladdin's Cave for Physicists

    CERN Multimedia

    2001-01-01

    Building 887 on the Prévessin site is home to numerous experiments bringing together physicists and engineers from around the world. Its diversity makes the huge building a replica of CERN in miniature. The Installation unit of the SL EA group in front of the support structure for the ATLAS muon chambers. From left to right, seated: Pierre Gimenez, Yves Bonnet, Yves Naveau, Alain Pinget, Christian Becquet, Camille Adenot; standing: Philippe Guillot, Thierry Reynes, Monserrat Zurita-Perez, Claude Ferrari et Denis Gacon. The big wheel to be used for the ATLAS muon chambers (see below) is much the most spectacular installation currently occupying Building 887. But it is far from being the only attraction. Push open the heavy doors of this immense hall and it is a bit like entering a physicists' Aladdin's cave. The building, 55 metres wide and 300 metres long, is a treasure trove of engineering and technology, a CERN in miniature, housing dozens of collaborations from all over the world. With its 150...

  17. What physicists should know about finance

    Science.gov (United States)

    Schmidt, Anatoly B.

    2005-05-01

    There has been growing interest in Econophysics, i.e. analysis and modeling of financial time series using the theoretical Physics concepts (scaling, fractals, chaos). Besides the scientific stimuli, this interest is backed by perception that the financial industry is a viable alternative for those physicists who are not able or are not willing to pursue an academic career. However, the times when any Ph.D. in Physics had a chance to find a job on the Wall Street are gone (if they ever existed). Indeed, not every physicist wields the stochastic calculus, non-normal statistical distributions, and the methods of time series analysis. Moreover, now that many universities offer courses in mathematical finance, the applicants for quantitative positions in finance are expected to know such concepts as option pricing, portfolio management, and risk measurement. Here I describe a synthetic course based on my book [1] that outlines both worlds: Econophysics and Mathematical Finance. The course may be offered as elective for senior undergraduate or graduate Physics majors.

  18. Decreased Stress Levels in Nurses: A Benefit of Quiet Time.

    Science.gov (United States)

    Riemer, Heather C; Mates, Joanna; Ryan, Linda; Schleder, Bonnie J

    2015-09-01

    The benefits of quiet time, a therapeutic method of improving the health care environment, have been evaluated in patients, but only a few studies have examined the effects of quiet time on intensive care nurses. To evaluate the effects of implementing quiet time in a medical-surgical intensive care unit on levels of light, noise, and nurses' stress. Quiet time consisted of turning down the unit lights for a designated time. Levels of light, noise, and nurses' stress were measured. Nurses' stress levels were measured by using a 100-point visual analog scale; unit noise, by using a digital sound level meter (model 407736, Extech Instruments); and unit light, by using an illumination light meter (model 615, Huygen Corporation). Measurements were obtained 30 minutes before and 30 minutes, 1 hour, and 2 hours after implementation of quiet time. Analysis of variance and comparisons of means indicated that both light levels and nurses' stress levels were significantly decreased after quiet time (both P quiet time, but the decrease was not significant (P = .08). Use of quiet time resulted in decreased light levels and decreased stress levels among nurses. Quiet time is an easily performed energy-saving intervention to promote a healthy work environment. ©2015 American Association of Critical-Care Nurses.

  19. Solar wind conditions for a quiet magnetosphere

    International Nuclear Information System (INIS)

    Kerns, K.J.; Gussenhoven, M.S.

    1990-01-01

    The conditions of the solar wind that lead to a quiet magnetosphere are determined under the assumption that the quiet or baseline magnetosphere can be identified by prolonged periods of low values of the am index. The authors analyzed solar wind data from 1978 to 1984 (7 years) during periods in which am ≤ 3 nT to identify those solar wind parameters that deviate significantly from average values. Parallel studies were also performed for prolonged periods of Kp = 0, 0+ and AE z ) show distinctive variations from average values. They independently varied these solar wind parameters and the length of time the conditions must persist to minimize am. This was done with the additional requirement that the conditions yield a reasonable number of occurrences (5% of the data set). The resulting baseline conditions are V ≤ 390 km/s; 180 degree - arctan |B y /B z | ≤ 101 degree, when b z ≤ 0 (no restriction on B z positive); B ≤ 6.5 nT; and persistence of these conditions for at least 5 hours. Minimizing the am index does not require a clear upper limit on the value of B z as might be anticipated from the work of Gussenhoven (1988) and Berthelier (1980). Apparently, this is a result of the requirement that the conditions must occur 5% of the time. When the requirement is lowered to 1% occurrence, an upper limit to B z emerges

  20. Dynamics of the quiet polar cap

    International Nuclear Information System (INIS)

    Carlson, H.C. Jr.

    1990-01-01

    Work in the past has established that a few percent of the time, under northward interplanetary magnetic field and thus magnetically quiet conditions, sun aligned arcs are found in the polar cap with intensities greater than the order of a kilo Rayleigh in the visible. Here we extend this view. We first note that imaging systems with sensitivity down to tens of Rayleighs in the visible find sun aligned arcs in the polar cap far more often, closer to half the time than a few percent. Furthermore, these sun aligned arcs have simple electrodynamics. They mark boundaries between rapid antisunward flow of ionospheric plasma on their dawn side and significantly slower flow, or even sunward flow, on their dusk side. Since the sun aligned arcs are typically the order of 1000 km to transpolar in the sun-earth direction, and the order of 100 km or less in the dawn-dusk direction, they demarcate lines of strongly anisotropic ionospheric flow shears or convection cells. The very quiet polar cap (strongly northward IMF) is in fact characterized by the presence of sun aligned arcs and multiple highly anisotropic ionospheric flow shears. Sensitive optical images are a valuable diagnostic with which to study polar ionospheric convection under these poorly understood conditions. (author)

  1. Influence of damping coefficient from permanent magnets on chatter formation during end milling of titanium alloy (Ti-6Al-4V)

    International Nuclear Information System (INIS)

    Sulaiman, S A; Amin, A N

    2015-01-01

    In machining operations, chatter is undesirable due to its adverse effects on the product quality, operation cost, machining accuracy and machine tool life. It is also responsible for reducing output. Chatter is a self-excitation phenomenon occurring in machine tools, in which the cutting process tends to lower the damping capacity of the machine structural components ending in an unstable behavior of the system. Chatter arises due to resonance when the vibrations of the instability of chip formation and the natural vibration modes of the machine-system components coincide. This paper focuses on the influence of damping coefficient from permanent magnets on chip serration frequency as an approach of minimizing chatter in end milling of Titanium alloy (Ti6Al4V). The method consists of two ferrite permanent magnet bars (dimensions: 1' × 6' × 3'), mounted 5mm from the cutting tool using a specially designed fixture which provided a uniform magnetic field of 2500-2700 Gausses. A titanium alloy Ti6Al4V block was then end milled using uncoated WC-Co inserts. A sequence of 15 experimental runs was conducted based on a small Central Composite Design (CCD) model in Response Surface Methodology (RSM). The primary (independent) parameters were: cutting speed, feed, and depth of cut. The data acquisition system comprised a vibration sensor (accelerometer) and a signal conditioning unit was used to measure the vibration data. The resultant vibrations were then analyzed using the DASYLab 5.6 software. Machining tests were conducted for two different conditions - with and without the application of magnets. Scanning Electron Microscope (SEM) was used to measure the chip segmentations. The SEM analysis of chip serrations demonstrated that the chip serration frequency were more stable while cutting under the presence of permanent magnets due to lower intensity of chatter. (paper)

  2. Influence of damping coefficient from permanent magnets on chatter formation during end milling of titanium alloy (Ti-6Al-4V)

    Science.gov (United States)

    Sulaiman, S. A.; Amin, A. N.

    2015-12-01

    In machining operations, chatter is undesirable due to its adverse effects on the product quality, operation cost, machining accuracy and machine tool life. It is also responsible for reducing output. Chatter is a self-excitation phenomenon occurring in machine tools, in which the cutting process tends to lower the damping capacity of the machine structural components ending in an unstable behavior of the system. Chatter arises due to resonance when the vibrations of the instability of chip formation and the natural vibration modes of the machine-system components coincide. This paper focuses on the influence of damping coefficient from permanent magnets on chip serration frequency as an approach of minimizing chatter in end milling of Titanium alloy (Ti6Al4V). The method consists of two ferrite permanent magnet bars (dimensions: 1" × 6" × 3"), mounted 5mm from the cutting tool using a specially designed fixture which provided a uniform magnetic field of 2500-2700 Gausses. A titanium alloy Ti6Al4V block was then end milled using uncoated WC-Co inserts. A sequence of 15 experimental runs was conducted based on a small Central Composite Design (CCD) model in Response Surface Methodology (RSM). The primary (independent) parameters were: cutting speed, feed, and depth of cut. The data acquisition system comprised a vibration sensor (accelerometer) and a signal conditioning unit was used to measure the vibration data. The resultant vibrations were then analyzed using the DASYLab 5.6 software. Machining tests were conducted for two different conditions - with and without the application of magnets. Scanning Electron Microscope (SEM) was used to measure the chip segmentations. The SEM analysis of chip serrations demonstrated that the chip serration frequency were more stable while cutting under the presence of permanent magnets due to lower intensity of chatter.

  3. Paths to Licensure: Things Physicists Should Know

    Science.gov (United States)

    Stewart, Gay; Stewart, John

    2016-03-01

    The path to licensure can be quite complicated, and can thwart a physics department's efforts to produce more and better prepared high school physics teachers. Each state has different pathways to licensure. Acronyms like CAEP and SPA are not within the normal physicist's vocabulary. Some understanding of this topic can allow physics faculty advisers to help our students so that fewer are derailed on their path to the classroom, or take a path that will leave them less well prepared if they do find themselves there. Examples of different approaches that work within state licensure systems from two different states will be presented. Physics teacher preparation efforts in both Arkansas and West Virginia have been supported in part by the Physics Teacher Education Coalition (PhysTEC).

  4. ALICE physicists receive 2014 Lise Meitner Prize

    CERN Multimedia

    Katarina Anthony

    2014-01-01

    On Wednesday, 3 September, four ALICE physicists were presented with the European Physical Society's 2014 Lise Meitner Prize for their outstanding contributions to nuclear physics (see here).   ALICE collaboration members Johanna Stachel (Heidelberg University, Germany), Peter Braun-Munzinger (GSI, Germany), Paolo Giubellino (INFN Turin, Italy, and CERN) and Jürgen Schukraft (CERN) were presented with their awards at a private ceremony held in the Globe of Science and Innovation. In addition to members of the ALICE collaboration, the ceremony was attended by members of the CERN Management including the Director-General, Rolf Heuer, as well as the EPS Nuclear Physics Board Chair, Douglas MacGregor, and the EPS Lise Meitner Prize Committee Chair, Victor Zamfir. For more information, please see "EPS honours CERN's heavy-ion researchers".  From left to right: Douglas MacGregor (EPS); Prize recipients Jürgen Schukraft,&a...

  5. A course in mathematical methods for physicists

    CERN Document Server

    Herman, Russell L

    2014-01-01

    Based on the author’s junior-level undergraduate course, this introductory textbook is designed for a course in mathematical physics. Focusing on the physics of oscillations and waves, A Course in Mathematical Methods for Physicists helps students understand the mathematical techniques needed for their future studies in physics. It takes a bottom-up approach that emphasizes physical applications of the mathematics. The book offers: •A quick review of mathematical prerequisites, proceeding to applications of differential equations and linear algebra •Classroom-tested explanations of complex and Fourier analysis for trigonometric and special functions •Coverage of vector analysis and curvilinear coordinates for solving higher dimensional problems •Sections on nonlinear dynamics, variational calculus, numerical solutions of differential equations, and Green's functions

  6. C++ FOR PARTICLE PHYSICISTS By Paul Kunz

    CERN Document Server

    TECHNICAL TRAINING; Tel. 74460

    2001-01-01

    Please note that Paul Kunz will be giving his very popular and highly recommended C++ course again on March 5 to 9. The course costs 200 CHF, and advance registration is required. People with CERN EDH accounts can apply electronically directly from the Web course description page : http://www.cern.ch/Training/ENSTEC/P9798/Software/cpppp_e.htm Team Visitors should ask their Group Leader to send an e-mail to the DTO of EP Division, M. Burri, referring to the 'C++ for Particle Physicists' course and giving their name, CERN ID number, the Team account number to which the course fee should be charged, and VERY IMPORTANTLY an email address to which an invitation to the course can be sent.

  7. C++ FOR PARTICLE PHYSICISTS by Paul Kunz

    CERN Document Server

    Technical Training; Tel. 74460

    2001-01-01

    Please note that Paul Kunz will be giving his very popular and highly recommended C++ course again on March 5 to 9. The course costs 200 CHF, and advance registration is required. People with CERN EDH accounts can apply electronically directly from the Web course description page : http://www.cern.ch/Training/ENSTEC/P9798/Software/cpppp_e.htm Team Visitors should ask their Group Leader to send an e-mail to the DTO of EP Division, M. Burri, referring to the 'C++ for Particle Physicists' course and giving their name, CERN ID number, the Team account number to which the course fee should be charged, and VERY IMPORTANTLY an email address to which an invitation to the course can be sent.

  8. Improving the workplace environment for female physicists

    Science.gov (United States)

    Butcher, Gillian

    2013-03-01

    The ideal workplace is one in which women and men can work to their potential and are respected and recognized for their contribution. But what are the conditions that would create this environment, and how can we achieve this? This paper highlights some of the best practices, discussed in a single-session workshop, to improve the workplace environment for female (and male) physicists. While there are many actions that can be taken at the personal, local, and even national level, it is necessary to understand when the issues have broader societal implications. Likewise, working toward the ideal environment should not lead us to ignore the necessity of training and assisting women to work effectively in the existing environment.

  9. Academic Training: Practical Statistics for Particle Physicists

    CERN Multimedia

    2006-01-01

    2006-2007 ACADEMIC TRAINING PROGRAMME LECTURE SERIES 9, 10, 11, 12, 13 October from 11:00 to 12:00 - Main Auditorium, bldg. 500, TH Auditorium, bldg 4, 3rd floor, on 13 October Practical Statistics for Particle Physicists L. LYONS, University of Oxford, GB Lecture 1: Learning to love the errror matrix Introductory remarks. Conditional probability. Statistical and systematic errors. Combining results Binomial, Poisson and 1-D Gaussian 2-D Gaussian and the error matrix. Understanding the covariance. Using the error matrix. Estimating the error matrix. Combining correlated measurements Lecture 2: Parameter determination by likelihood: Do's and don'ts Introduction to likelihood. Error estimate. Simple examples: (1) Breit Wigner (2) Lifetime binned and unbinned likelihood several parameters extended maximum likelihood. Common misapprehensions: Normalisation delta(lnL) = 1/2 rule and coverage Integrating the likelihood Unbinned L_max as goodness of fit Punzi effect Lecture 3: Chi-squared and hypothesis test...

  10. Tensor calculus for engineers and physicists

    CERN Document Server

    de Souza Sánchez Filho, Emil

    2016-01-01

    This textbook provides a rigorous approach to tensor manifolds in several aspects relevant for Engineers and Physicists working in industry or academia. With a thorough, comprehensive, and unified presentation, this book offers insights into several topics of tensor analysis, which covers all aspects of N dimensional spaces. The main purpose of this book is to give a self-contained yet simple, correct and comprehensive mathematical explanation of tensor calculus for undergraduate and graduate students and for professionals. In addition to many worked problems, this book features a selection of examples, solved step by step. Although no emphasis is placed on special and particular problems of Engineering or Physics, the text covers the fundamentals of these fields of science. The book makes a brief introduction into the basic concept of the tensorial formalism so as to allow the reader to make a quick and easy review of the essential topics that enable having the grounds for the subsequent themes, without need...

  11. Gustav-Hertz-Prize for CERN Physicist

    CERN Multimedia

    2004-01-01

    Klaus Blaum, of GSI Darmstadt and project leader of the ISOLTRAP experiment at CERN, will receive the 2004 Gustav-Hertz-Prize for his outstanding work on the mass determination of unstable atomic nuclei. Blaum extended the measuring capability of the ISOLTRAP experiment at the ISOLDE facility, which studies short-lived isotopes, by installing a source of carbon clusters. Using these carbon clusters as mass reference allows researchers to obtain higher-precision and absolute atomic mass measurements which are important to understand the weak interaction and the synthesis of chemical elements. The Gustav-Hertz-Prize is awarded to outstanding young physicists and is endowed with 7500 euro. It will be awarded at the Spring Conference of the German Physical Society in Munich on 24 March.

  12. International young physicists' tournament problems & solutions 2014

    CERN Document Server

    Gao, Wenli

    2016-01-01

    International Young Physicists' Tournament (Iypt), is one of the most prestigious international physics contests among high school students. This book is based on the solutions of 2014 Iypt problems. The authors are undergraduate students who participated in the Cupt (Chinese Undergraduate Physics Tournament). It is intended as a college level solution to the challenging open-ended problems. It provides original, quantitative solutions in fulfilling seemingly impossible tasks. This book is not limited to the tasks required by the problems and it is not confined to the models and methods in present literatures. Many of the articles include modification and extension to existing models in references, or derivation and computation based on fundamental physics. This book provides quantitative solutions to practical problems in everyday life. This is a good reference book for undergraduates, advanced high-school students, physics educators and curious public interested in the intriguing phenomena in daily life.

  13. Technical Training: C++ for Particle Physicists

    CERN Multimedia

    Monique Duval

    2004-01-01

    Please note that Paul Kunz will be giving his very popular and highly recommended C++ course again on 15 - 19 November. The course costs 200 CHF, and advance registration is required. People with CERN EDH accounts can apply electronically directly from the Web course description page: Team Visitors should ask their Group Leader to send an e-mail to the DTO of PH Department, M. Burri, referring to the 'C++ for Particle Physicists' course and giving their name, CERN ID number, the Team account number to which the course fee should be charged, and VERY IMPORTANTLY an email address to which an invitation to the course can be sent. ENSEIGNEMENT TECHNIQUE TECHNICAL TRAINING Monique Duval 74924 technical.training@cern.ch

  14. Technical Tarining: C++ for Particle Physicists

    CERN Multimedia

    Monique Duval

    2005-01-01

    Please note that Paul Kunz will be giving his very popular and highly recommended C++ course again on 7-11 March. The course costs 200 CHF, and advance registration is required. People with CERN EDH accounts can apply electronically directly from the Web course description page : http://cern.ch/TechnicalTraining/ENSTEC/p2002/Software/cpppp_e.asp Team Visitors should ask their Group Leader to send an e-mail to the DTO of PH Department, M. Burri, referring to the ‘C++ for Particle Physicists' course and giving their name, CERN ID number, the Team account number to which the course fee should be charged, and VERY IMPORTANTLY an email address to which an invitation to the course can be sent. ENSEIGNEMENT TECHNIQUE TECHNICAL TRAINING Monique Duval 74924 technical.training@cern.ch

  15. Technical Training: C++ for Particle Physicists

    CERN Multimedia

    Monique Duval

    2005-01-01

    Please note that Paul Kunz will be giving his very popular and highly recommended C++ course again on 7-11 March. The course costs 200 CHF, and advance registration is required. People with CERN EDH accounts can apply electronically directly from the Web course description page : http://cern.ch/TechnicalTraining/ENSTEC/p2002/Software/cpppp_e.asp Team Visitors should ask their Group Leader to send an e-mail to the DTO of PH Department, M. Burri, referring to the ‘C++ for Particle Physicists' course and giving their name, CERN ID number, the Team account number to which the course fee should be charged, and VERY IMPORTANTLY an email address to which an invitation to the course can be sent. ENSEIGNEMENT TECHNIQUE TECHNICAL TRAINING Monique Duval 74924 technical.training@cern.ch

  16. Technical Training: C++ for Particle Physicists

    CERN Multimedia

    Monique Duval

    2004-01-01

    Please note that Paul Kunz will be giving his very popular and highly recommended C++ course again on 15 - 19 November. The course costs 200 CHF, and advance registration is required. People with CERN EDH accounts can apply electronically directly from the Web course description page. Team Visitors should ask their Group Leader to send an e-mail to the DTO of PH Department, M. Burri, referring to the 'C++ for Particle Physicists' course and giving their name, CERN ID number, the Team account number to which the course fee should be charged, and VERY IMPORTANTLY an email address to which an invitation to the course can be sent. ENSEIGNEMENT TECHNIQUE TECHNICAL TRAINING Monique Duval 74924 technical.training@cern.ch

  17. Bird of passage recollections of a physicist

    CERN Document Server

    1985-01-01

    Here is the intensely personal and often humorous autobiography of one of the most distinguished theoretical physicists of his generation, Sir Rudolf Peierls. Born in Germany in 1907, Peierls was indeed a bird of passage," whose career of fifty-five years took him to leading centers of physics--including Munich, Leipzig, Zurich, Copenhagen, Cambridge, Manchester, Oxford, and J. Robert Oppenheimer''s Los Alamos. Peierls was a major participant in the revolutionary development of quantum mechanics in the 1920s and 1930s, working with some of the pioneers and, as he puts it, "some of the great characters" in this field. Originally published in 1988. The Princeton Legacy Library uses the latest print-on-demand technology to again make available previously out-of- print books from the distinguished backlist of Princeton University Press. These paperback editions preserve the original texts of these important books while presenting them in durable paperback editions. The goal of the Princeton Legacy Libr...

  18. School for Young High Energy Physicists

    CERN Document Server

    Evans, M E

    2003-01-01

    Forty-seven experimental particle physicists attended the 2002 Summer School, held, as usual, at The Cosener's House in Abingdon during September. The weather was glorious allowing a number of tutorials and impromptu seminars to take place in the lovely gardens. The lectures were of a high standard and were delivered and received enthusiastically, providing material for lively discussions in tutorials and elsewhere. The students each gave a ten-minute seminar and the general quality of the talks was impressive and the time keeping excellent. The activities described ranged from front-line physics analysis to preparations for the next generation of machines and detectors, and gave a clear indication of the breadth of particle physics activities in the UK

  19. Probabilistic interpretation of data a physicist's approach

    CERN Document Server

    Miller, Guthrie

    2013-01-01

    This book is a physicists approach to interpretation of data using Markov Chain Monte Carlo (MCMC). The concepts are derived from first principles using a style of mathematics that quickly elucidates the basic ideas, sometimes with the aid of examples. Probabilistic data interpretation is a straightforward problem involving conditional probability. A prior probability distribution is essential, and examples are given. In this small book (200 pages) the reader is led from the most basic concepts of mathematical probability all the way to parallel processing algorithms for Markov Chain Monte Carlo. Fortran source code (for eigenvalue analysis of finite discrete Markov Chains, for MCMC, and for nonlinear least squares) is included with the supplementary material for this book (available online).

  20. The "Quiet" Troubles of Low-Income Children

    Science.gov (United States)

    Weissbourd, Richard

    2009-01-01

    Most of the troubles poor at-risk children have are not "loud" problems like disruptive behavior or gang involvement. They are "quiet." The range of these problems is vast. Hunger, dehydration, asthma, obesity, and hearing problems can all insidiously trip children up in school. Some quiet problems are psychological--depression, anxiety, the fear…

  1. A Hybrid Scheme Motion Controller by Sliding Mode and Two-Degree-of-Freedom Controls to Minimize the Chattering

    Directory of Open Access Journals (Sweden)

    Chiu-Keng Lai

    2014-01-01

    Full Text Available Sliding mode control (SMC is rapped for the chattering due to high gain control. However, high gain control causes the system robust. For developing a system with robustness of SMC, a servo motor motion controller combining the two-degree-of-freedom (2DOF system and SMC is proposed. The discussed motion type is point-to-point control with the constraint of trapezoid velocity profile. SMC is designed to guide the motor motion to follow a predefined trail, and the inner 2DOF system is used to compensate the deterioration due to the adoption of load observer. The proposed hybrid system is realized on a PC-based motion controller, and the validness is verified by simulation and experimental results.

  2. The quiet revolution: decentralisation and fuel cells

    International Nuclear Information System (INIS)

    Aschenbrenner, N.

    2003-01-01

    This article discusses how major changes in the electricity supply industry can take place in the next few years due to market liberalisation and efforts to reduce the emission of greenhouse gasses. Decentralisation is discussed as being a 'mega-trend' and fuel cells in particular are emphasised as being a suitable means of generating heat and power locally, i.e. where they are needed. Also, the ecological advantages of using natural gas to 'fire' the fuel cell units that are to complement or replace coal-fired or gas-fired combined gas and steam-turbine power stations is discussed. Various types of fuel cell are briefly described. Market developments in the USA, where the power grid is extensive and little reserve capacity is available, are noted. New designs of fuel cell are briefly examined and it is noted that electricity utilities, originally against decentralisation, are now beginning to promote this 'quiet revolution'

  3. Quiet innovation adds flexibility to global lending

    International Nuclear Information System (INIS)

    Pavey, Nigel.

    1993-01-01

    Few major mandates were won or lost in the first quarter of 1993, as the energy industry adopted a conservative approach to its financing needs. However, indications are that energy companies are coming back to the syndicated loan market after this quiet first quarter. Already, Enron, Shell Oil and Coastal have mandated substantial new facilities. Many more companies are expected back in the market over the new few months, including at least one jumbo for a major international name. A number of the industry's top names report that pricing is once again getting more aggressive in response to the high level of liquidity among lenders and a shortage of new mandates over the last few months. (Author)

  4. Auroral ionospheric quiet summer time conductances

    International Nuclear Information System (INIS)

    Brekke, A.; Hall, C.

    1988-01-01

    The auroral zone E-region conductivities and conductances have been studied for 7 quiet time summer days. The Hall- and Pedersen conductances are found to follow the solar zenith variations in a rather regular fashion, and empirical formulas for these conductances are obtained. The choice of proper collision frequency models is found to be of great importance when deriving the conductances, and it is argued that some of the different results presented by other authors may be due to different models of the collision frequencies. The Hall- to Pedersen conductance ratios can only be used as an indicator of the energy of the precipitating auroral particles when the contribution from the background solar ionization is subtracted. When this is done this ratio takes much higher values than previously reported

  5. Great Physicists - The Life and Times of Leading Physicists from Galileo to Hawking

    International Nuclear Information System (INIS)

    Cropper, William H

    2002-01-01

    The author, a former American chemistry professor, has organized his book into nine parts with 29 chapters, covering, in a fairly historical sequence and systematic conceptual progression, all fundamentals of today's physics: i.e., mechanics, thermodynamics, electromagnetism, statistical mechanics, relativity, quantum mechanics, nuclear physics, particle physics, astronomy-astrophysics-cosmology. Obviously, the 20th century (when about 90% of professional physicists of all time worked) assumes with five topics the dominant role in this enterprise. For each topic, a small number (ranging from one to eight) of leading personalities is selected and the biographies of these 29 physicists, including two women (Marie Curie and Lise Meitner), are presented in some detail together with their achievements in the particular topic. Important relevant contributions of other scholars to each topic are also discussed. In addition, Cropper provides each of the topics with a short 'historical synopsis' justifying his selection of key persons. One may argue that concentrating on leading physicists constitutes an old-fashioned approach to displaying the history and contents of fundamental topics in physics. However, the mixture of biographies and explanation of leading contributions given here will certainly serve for a larger public, not just professional physicists and scientists, as a guide through the exciting development of physical ideas and discoveries. In general, the presentation of the material is quite satisfactory (with only few slips, e.g., in the Meitner story, where the author follows too closely a new biography) and gives the essence of the great advances in physics since the 15th century. One notices perhaps the limitation of the author in cases where no biography in English is available - this would also explain the omission of some of the main contributors to atomic and particle physics, such as Arnold Sommerfeld and Hideki Yukawa, or that French or Russian

  6. BOOK REVIEW: Great Physicists - The Life and Times of Leading Physicists from Galileo to Hawking

    Science.gov (United States)

    Cropper, William H.

    2002-11-01

    The author, a former American chemistry professor, has organized his book into nine parts with 29 chapters, covering, in a fairly historical sequence and systemtic conceptual progression, all fundamentals of today's physics: i.e., mechanics, thermodynamics, electromagnetism, statistical mechanics, relativity, quantum mechanics, nuclear physics, particle physics, astronomy-astrophysics-cosmology. Obviously, the 20th century (when about 90% of professional physicists of all time worked) assumes with five topics the dominant role in this enterprise. For each topic, a small number (ranging from one to eight) of leading personalities is selected and the biographies of these 29 physicists, including two women (Marie Curie and Lise Meitner), are presented in some detail together with their achievements in the particular topic. Important relevant contributions of other scholars to each topic are also discussed. In addition, Cropper provides each of the topics with a short 'historical synopsis' justifying his selection of key persons. One may argue that concentrating on leading physicists constitutes an old-fashioned approach to displaying the history and contents of fundamental topics in physics. However, the mixture of biographies and explanation of leading contributions given here will certainly serve for a larger public, not just professional physicists and scientists, as a guide through the exciting development of physical ideas and discoveries. In general, the presentation of the material is quite satisfactory (with only few slips, e.g., in the Meitner story, where the author follows too closely a new biography) and gives the essence of the great advances in physics since the 15th century. One notices perhaps the limitation of the author in cases where no biography in English is available - this would also explain the omission of some of the main contributors to atomic and particle physics, such as Arnold Sommerfeld and Hideki Yukawa, or that French or Russian readers

  7. Universities prepare as physicists plan to pop protons

    CERN Multimedia

    2007-01-01

    "The world's largest science experiment, a physics experiment designed to determine the nature of matter, will produce a mountain of data. And because the world's physicists cannot move to the mountain, an army of computer research scientists is preparing to move the mountain to the physicists." (3 pages)

  8. Academic Training: Cosmology for particle physicists

    CERN Multimedia

    Françoise Benz

    2005-01-01

    2004-2005 ACADEMIC TRAINING PROGRAMME LECTURE SERIES 9, 10, 11, 12 & 13 May from 11.00 to 12.00 hrs - Main Auditorium, bldg. 500 on 9, 10, 12 and 13 May, Council Chamber, bldg. 503, on 11 May Cosmology for particle physicists S. CARROLL / Enrico Fermi Institute, Univ. of Chicago, USA The past few years have seen dramatic breakthroughs and spectacular and puzzling discoveries in astrophysics and cosmology. We know much about the universe, but understand very little. Open questions include the nature of the dark matter and dark energy, the origin of the matter/antimatter asymmetry, the possibility of inflation, and the role of string theory and extra dimensions in the early universe. All of these issues impact strongly on, and will be heavily influenced by, upcoming experiments in particle physics. I will give an overview of current questions at the overlap of cosmology and particle physics, and discuss some theoretical and experimental questions likely to be important in the near future. ENSEIG...

  9. Academic Training: Cosmology for particle physicists

    CERN Multimedia

    Françoise Benz

    2005-01-01

    2004-2005 ACADEMIC TRAINING PROGRAMMELECTURE SERIES9, 10, 11, 12 & 13 Mayfrom 11.00 to 12.00 hrs - Main Auditorium, bldg. 500 on 9, 10, 12 and 13 May, Council Chamber, bldg. 503, on 11 MayCosmology for particle physicistsS. CARROLL / Enrico Fermi Institute, Univ. of Chicago, USAThe past few years have seen dramatic breakthroughs and spectacular and puzzling discoveries in astrophysics and cosmology. We know much about the universe, but understand very little. Open questions include the nature of the dark matter and dark energy, the origin of the matter/antimatter asymmetry, the possibility of inflation, and the role of string theory and extra dimensions in the early universe. All of these issues impact strongly on, and will be heavily influenced by, upcoming experiments in particle physics. I will give an overview of current questions at the overlap of cosmology and particle physics, and discuss some theoretical and experimental questions likely to be important in the near future.ENSEIGNEMENT ACADEMIQUEAC...

  10. Academic Training: Cosmology for particle physicists

    CERN Multimedia

    Françoise Benz

    2005-01-01

    2004-2005 ACADEMIC TRAINING PROGRAMME LECTURE SERIES 9, 10, 11, 12 & 13 May from 11.00 to 12.00 hrs - Main Auditorium, bldg. 500 on 9, 10, 12 and 13 May, Council Chamber, bldg. 503, on 11 May Cosmology for particle physicists S. CARROLL / Enrico Fermi Institute, Univ. of Chicago, USA The past few years have seen dramatic breakthroughs and spectacular and puzzling discoveries in astrophysics and cosmology. We know much about the universe, but understand very little. Open questions include the nature of the dark matter and dark energy, the origin of the matter/antimatter asymmetry, the possibility of inflation, and the role of string theory and extra dimensions in the early universe. All of these issues impact strongly on, and will be heavily influenced by, upcoming experiments in particle physics. I will give an overview of current questions at the overlap of cosmology and particle physics, and discuss some theoretical and experimental questions likely to be important in the near future. ENSEIGNEME...

  11. Lasers take physicists back to school

    CERN Multimedia

    Katarina Anthony

    2012-01-01

    This week saw the First International School on Laser Applications at Accelerators held in GANIL (France). Organised by the LA3NET project – of which CERN is a partner – the school was a singular opportunity for accelerator and laser physicists to meet and discuss the future of the merging areas.   As an EU-funded training network, LA3NET has brought together 27 partner institutes to train early stage researchers in the field of laser applications. Though the network kickedoff only a few months ago, it has already filled 15 of its 17 fellow positions, including three in CERN’s BE and EN Departments. The five-day International School on Laser Applications at Accelerators was the first big event organised by LA3NET, and united participants from both inside and outside the project. “This was the first time a school had linked laser and accelerator physics at such a fundamental level,” says Carsten P. Welsch, a former CERN fellow who now coordinates t...

  12. Why are there so few female physicists?

    CERN Multimedia

    Marianne Johansen

    Physics has always had a relatively low proportion of female students and researchers. In the EU there are on average 33% female PhD-graduates in the physical sciences, while the percentage of female professors amounts to 9% [1]. At CERN the proportion is even less with only 6.6 % of the research staff being women [2]. The fact that there is no proportional relationship between the number of PhD-graduates and professors also suggests women are less likely to succeed in an academic career than men [1]. A typical ATLAS plenary meeting. More laptops than women... Is the low representation of women in physics a problem, do we actually need more female physicists? In my view this question has to be answered from three perspectives, the perspective of society, the perspective of science and the perspective of women. The perspective of society Starting from the viewpoint of society, several issues can be raised. Firstly, physics is a field of innovation. Many technological advancements having a huge imp...

  13. Technical Training: C++ for Particle Physicists

    CERN Multimedia

    2004-01-01

    If you wish to participate in one of the following courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at: http://www.cern.ch/Training/ or fill in an "application for training" form available from your Divisional Secretariat or from your DTO (Divisional Training Officer). Applications will be accepted in the order of their receipt. TECHNICAL TRAINING Monique Duval tel. 74924 technical.training@cern.ch Please note that Paul Kunz will be giving his very popular and highly recommended C++ course again on 8 - 12 March. The course costs 200 CHF, and advance registration is required. People with CERN EDH accounts can apply electronically directly from the Web course description page : http://cern.ch/TechnicalTraining/ENSTEC/p2002/Software/cpppp_e.asp Team Visitors should ask their Group Leader to send an e-mail to the DTO of PH Department, M. Burri, referring to the ‘C++ for Particle Physicists' ...

  14. Technical Training: C++ for Particle Physicists

    CERN Multimedia

    2004-01-01

    If you wish to participate in one of the following courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at: http://www.cern.ch/Training/ or fill in an "application for training" form available from your Divisional Secretariat or from your DTO (Divisional Training Officer). Applications will be accepted in the order of their receipt. TECHNICAL TRAINING Monique Duval tel. 74924 technical.training@cern.ch Please note that Paul Kunz will be giving his very popular and highly recommended C++ course again on 8 - 12 March. The course costs 200 CHF, and advance registration is required. People with CERN EDH accounts can apply electronically directly from the Web course description page: http://cern.ch/TechnicalTraining/ENSTEC/p2002/Software/cpppp_e.asp Team Visitors should ask their Group Leader to send an e-mail to the DTO of PH Department, M. Burri, referring to the ‘C++ for Particle Physicists' c...

  15. Radioactivation in ''quiet'' sections of the SSC [Superconducting Super Collider

    International Nuclear Information System (INIS)

    Cossairt, J.D.

    1987-10-01

    Estimation of induced radioactivity in the ''quiet'' sections of the SSC is approached using elementary methods. Estimates are given of total activity and residual dose rates on the surface of magnets in the quiet regions, as well as estimates of the activation of tunnel concrete. The residual radioactivity produced in the magnets and concrete walls of the ''quiet'' regions of the SSC are found to be quite small and of little radiological impact, but that simple scaling could yield results for more ''lossy'' regions

  16. Chatter, reverberation, and the static in the system: Noise in American cinema culture

    Science.gov (United States)

    Ward, Meredith C.

    Noise is unwelcome in film culture; it has long been associated with disruption, counter-productivity, and discord. Yet taking a historical approach to noise and connecting its various manifestations to American auditory culture at large reveals noise to be a historiographically productive category for study. Approaching noise through its effects on four areas of American cinema culture---the social, technological, acoustical, and aesthetic---in four key historical moments, this dissertation demonstrates that listening to noise can explain conflicts in the history of film sound and audiences. Examples include silencing the social noise of rowdy spectators during the nickelodeon period; the Academy of Motion Picture Arts and Science's attempt to compete with Bell Laboratories with technological, noise-based research during film's transition to sound; the rise of acoustical design in film theaters to quash noise and produce contemplative listening in film spectators; and the user's current navigation of her attention between the sounds of media and urban life while viewing films on smartphones. In each case, the presence of noise has produced tensions that reveal the power structure of film culture. Terming sound "noise" is an act of judgment that has social ramifications, and the struggle against noise is also a struggle between groups vying for power within cinema culture: conflict over who may determine whose sound is "noise"; competition between industries regarding who owns sound knowledge; debates about which sounds are "noise" and which are legitimate components of the cinema experience; and tensions between our established expectations of noisy public space and the ways in which we create quiet spheres via mobile listening. Looking to the aural historical dialogues in which cinema culture partook, this project outlines the conditions of possibility within which listening to the cinema emerged in these periods. Understanding these historical contexts, we can

  17. Quiet pupils can be effective learners

    Directory of Open Access Journals (Sweden)

    Gunnhildur Óskarsdóttir

    2015-11-01

    Full Text Available This paper investigates the importance for pupils’ learning of being generally visibly active participant in a classroom discussion. A class of six year-old pupils was taught about the human skeletal system and other organs. To determine what they had learnt, they were asked to produce drawings before and after the course of teaching. The pupils’ participation in the class discussion during the course of teaching was given values on a scale from 1–8, the most talkative receiving the value 1 and the least talkative (or most quiet the value 8. The study showed that the less talkative the pupils were in the discussion the more they gained from the teaching. The results could not be accounted for by ceiling effects and similar patterns obtained across the materials used support the robustness of the findings. The study suggests that it cannot be assumed that participating in classroom discussion during the learning process is a necessary precondition for learning.

  18. Near IR observations of Quiet Chromosphere

    Science.gov (United States)

    Prasad Choudhary, Debi; Deng, N.; Tejamoortula, U.; Penn, M. J.

    2009-05-01

    We have carried out the observations of quiet solar limb during April 29 to May 1, 2008, March 9-13, 2009 using the vertical spectrograph at the focal plane of McMath-Pierce telescope at Kitt Peak National Observatory. The solar limb was mostly featureless during the observations. The New Infrared Array (NAC) at the exit port of the spectrograph has been used to record the limb spectrum at HeI 1083.0 nm, Hydrogen Paschen beta at 1281.8 nm and Brackett gamma 2165.5 nm wavelength regions. The NAC is a 1024 x 1024 InSb Alladin III Detector operating over 1-5 micron range with high density sampling at 0.018 arc second/pixel. The all-reflective optical train minimizes number of surfaces and eliminates ghosts leading to low scatter, ghost-free optics. The close-cycle cryogenic provides a stable cooling environment over six hour period with an accuracy of about 0.01K leading to low dark current. The low read out noise combined with low scattered light and dark current makes NAC an ideal detector for making high quality infrared spectral observations of solar limb. In this presentation, we shall compare the line parameters of these lines around the solar disk. Acknowledgements: This work is supported by NSF under grant ATM 05-48952 and by NASA under grant NNX08AQ32G.

  19. Quiet swimming at low Reynolds number

    DEFF Research Database (Denmark)

    Andersen, Anders Peter; Wadhwa, Navish; Kiørboe, Thomas

    2015-01-01

    The stresslet provides a simple model of the flow created by a small, freely swimming and neutrally buoyant aquatic organism and shows that the far field fluid disturbance created by such an organism in general decays as one over distance squared. Here we discuss a quieter swimming mode that elim......The stresslet provides a simple model of the flow created by a small, freely swimming and neutrally buoyant aquatic organism and shows that the far field fluid disturbance created by such an organism in general decays as one over distance squared. Here we discuss a quieter swimming mode...... that eliminates the stresslet component of the flow and leads to a faster spatial decay of the fluid disturbance described by a force quadrupole that decays as one over distance cubed. Motivated by recent experimental results on fluid disturbances due to small aquatic organisms, we demonstrate that a three......-Stokeslet model of a swimming organism which uses breast stroke type kinematics is an example of such a quiet swimmer. We show that the fluid disturbance in both the near field and the far field is significantly reduced by appropriately arranging the propulsion apparatus, and we find that the far field power laws...

  20. Quiet swimming at low Reynolds number

    Science.gov (United States)

    Andersen, Anders; Wadhwa, Navish; Kiørboe, Thomas

    2015-04-01

    The stresslet provides a simple model of the flow created by a small, freely swimming and neutrally buoyant aquatic organism and shows that the far field fluid disturbance created by such an organism in general decays as one over distance squared. Here we discuss a quieter swimming mode that eliminates the stresslet component of the flow and leads to a faster spatial decay of the fluid disturbance described by a force quadrupole that decays as one over distance cubed. Motivated by recent experimental results on fluid disturbances due to small aquatic organisms, we demonstrate that a three-Stokeslet model of a swimming organism which uses breast stroke type kinematics is an example of such a quiet swimmer. We show that the fluid disturbance in both the near field and the far field is significantly reduced by appropriately arranging the propulsion apparatus, and we find that the far field power laws are valid surprisingly close to the organism. Finally, we discuss point force models as a general framework for hypothesis generation and experimental exploration of fluid mediated predator-prey interactions in the planktonic world.

  1. A physicist's views on energy problems

    International Nuclear Information System (INIS)

    Revol, Ch.J.P.

    2003-01-01

    The energy problem is one of the most serious challenges facing our civilization. The issue is not whether there are sufficient energy resources in the short- or medium-term, even though world consumption is already considerable, but rather how can we satisfy the world's current and future energy requirements without compromising the planet's ecological balance and how can we ensure an equitable distribution of an acceptable level of energy resources between all countries, including developing countries? The problem has now become a worldwide one with consequences that are also world-wide. The developed countries have lost control of the Earth's ecological future. In 1990 the developing countries consumed only a quarter of the world's energy resources. By 2020 they will already be consuming 60 %. New environmental) friendly technologies will have to be invented to produce sufficient energy at competitive prices. It is not just in the interests of the developed countries to help developing countries to acquire these new technologies, it is also their moral duty to do so. Any injunction to the developing countries not to burn coal and oil as we have done to date would be indefensible. Nuclear energy appears to be one of the possible ways of combating global warming since it produces no CO 2 and is currently the only source or energy capable of meeting demand for several centuries at least. This is the general background to the proposal of Carlo Rubbia and his team of CERN physicists for a new way of exploiting nuclear fission energy which addresses the question: can one imagine fission-based nuclear energy that would be acceptable to our society in other words, an ecological source of nuclear energy? (author)

  2. Cyclical Variation of the Quiet Corona and Coronal Holes

    Indian Academy of Sciences (India)

    tribpo

    Key words. Coronagraphs—solar activity cycle—solar corona—total ... can be divided into the quiet sun (including coronal holes) and active regions. The ... regions has attracted attention and is termed as 'the extended solar cycle'. Here the.

  3. Lithuanian female physicists: Reality and plans for the future

    Science.gov (United States)

    Šatkovskienė, Dalia; Giriunienė, Ramutė; Ruželė, Živilė; Rutkunienė, Živilė

    2013-03-01

    Changes in the issue of women in physics in Lithuanian in the three years since the 3rd IUPAP International Conference on Women in Physics are discussed on the basis of statistics as well as an exploratory study recently conducted among women physicists. The situation has changed slowly since 2008. However, the study shows that women physicists more clearly understand the inequities and the need for changes, including an active European Union mainstreaming policy targeted to ensure gender equality in the sciences, which gives hope for accelerating changes. Continued plans for improving women physicists' situation in Lithuania are discussed.

  4. Mário Schenberg: Physicist, politician and art critic

    International Nuclear Information System (INIS)

    Guzzo, M. M.; Reggiani, N.

    2015-01-01

    Mário Schenberg is considered one of the greatest theoretical physicists of Brazil. He worked in different fields of physics including thermodynamics, quantum mechanics, statistical mechanics, general relativity, astrophysics and mathematics. He was assistant of the Ukrainian naturalized Italian physicist Gleb Wataghin and worked with prestigious physicists like as the Brazilians José Leite Lopes and César Lattes, the Russian-born American George Gamow and the Indian astrophysicist Subrahmanyan Chandrasekhar. Besides, he was also an active politician and critic of art

  5. Liability from the view of the medical physicist

    International Nuclear Information System (INIS)

    Shalek, R.J.

    1980-01-01

    The negligent performance of professional duties is the most probable type of legal action against a medical physicist. A mistake resulting from ignorance or inadvertence is an example; an error in professional judgement is not negligence if an ordinary, prudent physicist in the same situation would have made the same decision. A physicist or any hospital employee has a duty to protect his employer from liability even to the extent of reporting to the hospital medical practices which could harm the patient. Suggestions for reducing legal risk include recommendations for professional knowledge, record keeping and outside verification of important elements of operating systems

  6. Modulation of cosmic rays on geomagnetically most quiet days

    Science.gov (United States)

    Agarwal Mishra, Rekha; Agarwal Mishra, Rekha; Mishra, Rajesh Kumar

    The aim of this work is to study the first three harmonics of cosmic ray intensity on geomagnetically quiet days over the period 1980-1990 for Deep River and Tokyo neutron monitoring stations. The amplitude of first harmonic remains high for Deep River having low cutoff rigidity as compared to Tokyo neutron monitor having high cutoff rigidity on quiet days.. The diurnal time of maximum significantly shifts to an earlier time as compared to the corotational/1800 Hr direction at both the stations having different cutoff rigidities. The time of maximum for first harmonic significantly shifts towards later hours and for second harmonic it shifts towards earlier hours at low cutoff rigidity station i.e. Deep River as compared to the high cut off rigidity station i.e. Tokyo on quiet days. The amplitude of semi/tri-diurnal anisotropy have a good positive correlation with solar wind velocity, while the others (i.e. amplitude and phase) have no significant correlation on quiet days for Deep River and Tokyo having different cutoff rigidity during 1980-1990. The solar wind velocity significantly remains in the range 350 to 425 km/s i.e. being nearly average on quiet days. The amplitude and direction of the anisotropy on quiet days are weakly dependent on high-speed solar wind streams for two neutron monitoring station of low and high cutoff rigidity threshold. The semi-diurnal amplitude has a significant anti-correlation, whereas the amplitude of third harmonic and direction of first harmonic has a good anti-correlation with IMF Bz and the product V x Bz on quiet days at Deep River station. However, the direction of first harmonic has a significant anti-correlation and the direction of second harmonic has a good anti-correlation with IMF Bz and the product V x Bz on quiet days at Tokyo station.

  7. The quiet Sun brightness temperature at 408 MHz

    International Nuclear Information System (INIS)

    Avignon, Y.; Lantos, P.; Palagi, F.; Patriarchi, P.

    1975-01-01

    The flux of the radio quiet Sun and the brightness temperature at 408 MHz (73cm) are derived from measurements with the E-W Nancay interferometer and the E-W arm of the Medicina North Cross. It is shown that the lowest envelopes, which defined the radio quiet Sun, correspond to transits of extended coronal holes across the disk of the Sun. (Auth.)

  8. 49 CFR 222.51 - Under what conditions will quiet zone status be terminated?

    Science.gov (United States)

    2010-10-01

    ...-Quiet Zones § 222.51 Under what conditions will quiet zone status be terminated? (a) New Quiet Zones... 49 Transportation 4 2010-10-01 2010-10-01 false Under what conditions will quiet zone status be terminated? 222.51 Section 222.51 Transportation Other Regulations Relating to Transportation (Continued...

  9. A quiet ego quiets death anxiety: humility as an existential anxiety buffer.

    Science.gov (United States)

    Kesebir, Pelin

    2014-04-01

    Five studies tested the hypothesis that a quiet ego, as exemplified by humility, would buffer death anxiety. Humility is characterized by a willingness to accept the self and life without comforting illusions, and by low levels of self-focus. As a consequence, it was expected to render mortality thoughts less threatening and less likely to evoke potentially destructive behavior patterns. In line with this reasoning, Study 1 found that people high in humility do not engage in self-serving moral disengagement following mortality reminders, whereas people low in humility do. Study 2 showed that only people low in humility respond to death reminders with increased fear of death, and established that this effect was driven uniquely by humility and not by some other related personality trait. In Study 3, a low sense of psychological entitlement decreased cultural worldview defense in response to death thoughts, whereas a high sense of entitlement tended to increase it. Study 4 demonstrated that priming humility reduces self-reported death anxiety relative to both a baseline and a pride priming condition. Finally, in Study 5, experimentally induced feelings of humility prevented mortality reminders from leading to depleted self-control. As a whole, these findings obtained from relatively diverse Internet samples illustrate that the dark side of death anxiety is brought about by a noisy ego only and not by a quiet ego, revealing self-transcendence as a sturdier, healthier anxiety buffer than self-enhancement. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  10. Cosmic microwave background polarization results from QUIET

    International Nuclear Information System (INIS)

    Buder, I.

    2014-01-01

    Despite the success of precision cosmology, cosmologists cannot fully explain the initial conditions of the Universe. Inflation, an exponential expansion in the first ∼ 10 -36 s, is a promising potential explanation. A generic prediction of inflation is odd-parity (B-mode) polarization in the cosmic microwave background (CMB). Q/U Imaging Experiment (QUIET) aimed at limiting or detecting this polarization. We built a pseudo-correlation microwave polarimeter as an array of mass-produced modules in the focal plane of a 1.4 m telescope. We used rotation around the absorbing ground screen, a new time-stream double-demodulation technique, and optimized optics in the design to reduce instrumental polarization. We observed with this instrument at the Atacama Plateau in Chile between October 2008 and December 2010. This paper describes the analysis and results of these observations from one of 2 parallel pipelines. We developed noise modeling, filtering and data selection following a blind-analysis strategy. Central to this strategy was a suite of null test, each motivated by a possible instrumental problem or systematic effect. We evaluated the systematic errors in the blind stage of the analysis before the result was known. We calculated the CMB power spectra using a pseudo-C l cross-correlation technique that suppressed contamination and made the result insensitive to noise bias. We measured the first 3 peaks of the E-mode spectrum at high significance and limited B-mode polarization. We measured the CMB polarization power at 25 ≤ l ≤ 975. We found no statistically significant deviation from ΛCDM model, and our results are consistent with zero BB and EB power. Systematic errors were well below our B-mode polarization limits. This systematic-error reduction was a strong demonstration of technology for application in more sensitive, next generation CMB experiments. (author)

  11. French physicist's brother denies links to Al Qaeda

    CERN Multimedia

    Overbye, Dennis

    2009-01-01

    "Days after the French authorities placed a physicist working in Switzerland under formal investigation in a terror case, a portrait of the man and his work has begun to emerge from interviews with officials and his lawyer"

  12. Physicists set new record for network data transfer

    CERN Multimedia

    2007-01-01

    "An international team of physicists, computer scientists, and network engineers joined forces to set new records for sustained data transfer between storage systems durint the SuperComputing 2006 (SC06) Bandwidth Challenge (BWC). (3 pages)

  13. From falling bodies to radiowaves: classical physicists and their discoveries

    International Nuclear Information System (INIS)

    Segre, E.

    1984-01-01

    This chronicle of physics and physicists traces the development of scientific thought from the works of the founding fathers - Galileo, Huggens and Newton - to the more recent discoveries of Maxwell, Boltzmann, and Gibbs

  14. Clinical training of medical physicists. IAEA experience in Asia

    International Nuclear Information System (INIS)

    McLean, D.

    2013-01-01

    Medical physicists make a major contribution to the safe and effective diagnosis and treatment of patients with cancer and other illnesses. The medical physicist's responsibilities include the major areas of dosimetry, treatment planning, quality assurance, image quality, optimization, equipment management, research, teaching, and radiation safety. With the increasing complexity of technological application to medicine the competence of trained physicists is critical to good patient care, with counter examples, sadly evident in the literature. The International Atomic Energy Agency (IAEA), in conjunction with international experts, including from Japan, has developed clinical training programmes that have been successfully implemented on a pilot basis in a number of countries in Asia. A new project is to begin in 2014 which will focus increasingly on the use of electronic teaching material and experiences, to assist medical physicists in clinical training increasingly in more remote locations in Asia. (author)

  15. Rice Physicist to direct $40M LHC Program

    CERN Multimedia

    2006-01-01

    "Rice Universty announced that physicist B. Paul Padley has been chosen to lead the scientific operations for one of the particle detector systems at the European Organization for Nuclear Research's Large Hadron Collider (LHC)."

  16. Structure and Dynamics of the Quiet Solar Chromosphere

    Science.gov (United States)

    Kalkofen, Wolfgang

    2002-04-01

    The grant supported research on the structure of the quiet, nonmagnetic chromosphere and on wave excitation and propagation in both the nonmagnetic chromosphere and the magnetic network. The work on the structure of the chromosphere culminated in the recognition that between two competing views of the solar chromosphere, older models by Avrett and collaborators (referred to as VAL) and the newer, dynamical model by Carlsson & Stein (referred to as CS), the clear decision is in favor of the older models, and this in spite of the evident lack of physics, which does not include wave motion and oscillations. The contrast between the static VAL models and the dynamical CS model can be stated most succinctly by comparing the temperature variation implied by the VAL models and the temperature fluctuations of the CS model, which are, respectively, of the order of 10% for the VAL model (at heights where hydrogen is 50% ionized) and a factor of 10 (at the upper boundary of their chromospheric model). The huge fluctuations of the CS model have never been observed, whereas the smaller temperature variations of the VAL models are consistent with ground-based and space-based observations. While it should be obvious which model describes the Sun and which one fails, the case is far from settled in the minds of solar physicists. Thus, much educational work remains to be done and, of course, more research to develop arguments that make the case more convincing. The research on waves and oscillations has been based on a unified theory of excitation of acoustic waves in the field-free atmosphere and of transverse and longitudinal waves in magnetic flux tubes located in the magnetic network by noting, first, that impulsive excitation of all these waves in gravitationally stratified media leads to oscillations at the respective cutoff frequencies and, second, that the observed oscillation frequencies in the nonmagnetic and magnetic parts of the chromosphere match corresponding cutoff

  17. Education and training of medical physicists in radiology

    International Nuclear Information System (INIS)

    Todorov, V.; Vassileva, J.

    2006-01-01

    Full text: Medical radiology is chronologically the first and widest field of work of medical physicists. Therefore the education and training of medical radiological physicists is of big importance for both diagnostics and therapy. The education of medical radiological physicists in Bulgaria is organized in two levels: university and postgraduate, which is a good achievement of Bulgarian educational system. University education is in the framework of the M. Sc. program in Medical physics with a prevalent training in medical radiological physics. Three universities in the country have been carrying out this education since more than ten years. Postgraduate education covers specialties Medical Radiological Physics and Radiation Hygiene. It is organized by the Medical University but the training is opened also to specialists outside the health care system. The interests in both levels of education and training in Medical Physics is increasing with about 40 trainees in last years. The university and postgraduate education has good quality in theory but still inadequate in practical aspects. The continuous training and qualification of medical physicists has also difficulties; the main reasons are insufficient technical and financial resources as well as the lack of interest of the staff of the training centers. The responsibilities for education and training of medical physicists in radiology should be shared between physicists and physicians in the country

  18. The Status of African American Physicists within the DOE Laboratories

    Science.gov (United States)

    Jackson, Keith

    2005-03-01

    In May 2002 there was a backpage article published in American Physical Society Newsletter by the President of the National Society of Black Physicists (NSBP). This article showed that of the 3372 professional physicists employed at the DOE national labs, only 11 are African American, which on a percentage basis is 4 times less than the total availability of Ph.D. African American physicists in the labor force. NSBP want to provide an update of the interaction between National Society of Black Physicists (NSBP) and the department of Energy in particular the Office of Science on the issue of employment of African American Physicists in scientific and technical. You might ask the following question: Why should the current generation of African American Physicists be concerned about their underepresentation on the scientific staffs of the DOE National Laboratories? The answer to this question may vary from person to person, but I would like to propose the following: The National Laboratories are the largest providers of career opportunities in Physics in the United States. There is a general view in the community; African Americans are not getting a return on their national investment in the DOE National Labs. Failure to engage with HBCU’s through their user facilities causes a training or skills deficit when it comes to preparing students to participate at the forefront of physics research. By rebuffing interactions with HBCU¹s, as many the laboratories have done, the national laboratories are in effect refusing to transfer scientific knowledge to the stakeholders in the African American community. The update will contain some additional information about NSBP proposals to solve the problem of underepresentation of African American and Hispanic physicists within the National Laboratories and how the Office of Science has response these proposals.

  19. TU-F-BRD-01: Biomedical Informatics for Medical Physicists

    International Nuclear Information System (INIS)

    Phillips, M; Kalet, I; McNutt, T; Smith, W

    2014-01-01

    Biomedical informatics encompasses a very large domain of knowledge and applications. This broad and loosely defined field can make it difficult to navigate. Physicists often are called upon to provide informatics services and/or to take part in projects involving principles of the field. The purpose of the presentations in this symposium is to help medical physicists gain some knowledge about the breadth of the field and how, in the current clinical and research environment, they can participate and contribute. Three talks have been designed to give an overview from the perspective of physicists and to provide a more in-depth discussion in two areas. One of the primary purposes, and the main subject of the first talk, is to help physicists achieve a perspective about the range of the topics and concepts that fall under the heading of 'informatics'. The approach is to de-mystify topics and jargon and to help physicists find resources in the field should they need them. The other talks explore two areas of biomedical informatics in more depth. The goal is to highlight two domains of intense current interest--databases and models--in enough depth into current approaches so that an adequate background for independent inquiry is achieved. These two areas will serve as good examples of how physicists, using informatics principles, can contribute to oncology practice and research. Learning Objectives: To understand how the principles of biomedical informatics are used by medical physicists. To put the relevant informatics concepts in perspective with regard to biomedicine in general. To use clinical database design as an example of biomedical informatics. To provide a solid background into the problems and issues of the design and use of data and databases in radiation oncology. To use modeling in the service of decision support systems as an example of modeling methods and data use. To provide a background into how uncertainty in our data and knowledge can be

  20. Clinical Training of Medical Physicists Specializing in Nuclear Medicine

    International Nuclear Information System (INIS)

    2011-01-01

    The application of radiation in human health, for both diagnosis and treatment of disease, is an important component of the work of the IAEA. The responsibility for the increasingly technical aspects of this work is undertaken by the medical physicist. To ensure good practice in this vital area, structured clinical training programmes are required to complement academic learning. This publication is intended to be a guide to the practical implementation of such a programme for nuclear medicine. There is a general and growing awareness that radiation medicine is increasingly dependent on well trained medical physicists who are based in a clinical setting. However an analysis of the availability of medical physicists indicates a large shortfall of qualified and capable professionals. This is particularly evident in developing countries. While strategies to increase educational opportunities are critical to such countries, the need for guidance on structured clinical training was recognized by the members of the Regional Cooperative Agreement for Research, Development and Training related to Nuclear Science and Technology (RCA) for the Asia-Pacific region. Consequently, a technical cooperation regional project (RAS6038) under the RCA programme was formulated to address this need in this region by developing suitable material and establishing its viability. Development of a clinical training guide for medical physicists specialising in nuclear medicine was started in 2009 with the appointment of a core drafting committee of regional and international experts. The publication drew on the experience of clinical training in Australia, Croatia and Sweden and was moderated by physicists working in the Asian region. The present publication follows the approach of earlier IAEA publications in the Training Course Series, specifically Nos 37 and 47, Clinical Training of Medical Physicists Specializing in Radiation Oncology and Clinical Training of Medical Physicists

  1. Accreditation of physicist in radiotherapy-past, present and future

    International Nuclear Information System (INIS)

    Howlett, S.

    2010-01-01

    Full text: Accreditation of medical physicists for clinical radiotherapy practice was commenced by the ACPSEM in 1988 by a group of experienced physicists interested in setting a benchmark of international standard by which to assess practising radiotherapy physicists. It is a voluntary, peer based examination process and leads to the award of Accreditation in Radiotherapy Equipment Commissioning and Quality Assurance (ARECQA). The responsible body within the ACPSEM is the Radiation Oncology Accreditation Panel (ROAP) under the umbrella of the Professional Standards Board(PSB). Over 130 physicists in Australia and New Zealand have been awarded ARECQA and it has been recognised by the radiotherapy professions and government bodies as a desirable and sometimes required, standard of qualification. With the implementation of the Training, Education and Accreditation Program (TEAP) by ACPSEM in 2003, a new Accreditation in Radiation Oncology Medical Physics (AROMP) was established in 2005. ARECQA will cease taking applications from experienced physicists on December 31st 2012 and only the AROMP pathway will be available. An external review of TEAP funded by the Commonwealth Government Department of Health and Ageing (DoHA), which is not yet publicly released, will have implications for AROMP in the future. This talk will review the development and progress of accreditation in radiation oncology medical physics in Australia and New Zealand, its place in the delivery of quality patient care, the relationship to ACPSEM registration, the current situation and future directions. (author)

  2. Dark energy and the quietness of the local Hubble flow

    International Nuclear Information System (INIS)

    Axenides, M.; Perivolaropoulos, L.

    2002-01-01

    The linearity and quietness of the local ( X (t 0 ) of dark energy obeying the time independent equation of state p X =wρ X . We find that dark energy can indeed cool the LHF. However the dark energy parameter values required to make the predicted velocity dispersion consistent with the observed value v rms ≅40 km/s have been ruled out by other observational tests constraining the dark energy parameters w and Ω X . Therefore despite the claims of recent qualitative studies, dark energy with time independent equation of state cannot by itself explain the quietness and linearity of the local Hubble flow

  3. Train medical physicist-urgent need for advanced radiotherapy

    International Nuclear Information System (INIS)

    Hareyama, Masato; Teshima, Teruki; Yamamoto, Tokihiro; Haga, Akihiro; Nakagawa, Keiichi; Uesaka, Mitsuru

    2008-01-01

    A Japanese advanced charged particle therapy for cancer that places fewer physical burdens on patients is leading the world and stereotactic radiotherapy and intensity-modulated radiotherapy (IMRT) have been implemented also as a high precision radiotherapy. For the further advancement and dissemination of the therapy, training and qualification of medical physicists has become more needed. Cancer professional train course plan has been performed at many universities in Japan partly to train medical physicists. This special issue consists of seven relevant articles from experts of academia. Medical physicists have been qualified by the Japan Radiological Society, but should have national qualification such as to carry out the R and D of therapy equipment. This has been supported by many academia such as the Japanese Society for Therapeutic Radiology and Oncology (JASTRO) but not by the Japan Association of Radiological Technologists (JART). (T. Tanaka)

  4. A CERN physicist receives the Gian Carlo Wick Medal

    CERN Multimedia

    2007-01-01

    T.D. Lee, Chairman of the Gian Carlo Wick Medal selection committee, André Martin, the 2007 recipient, and Antonino Zichichi, President of the World Federation of Scientists (WFS)(Copyright : WFS) The 2007 Gian Carlo Wick Gold Medal was presented to the CERN theoretical physicist André Martin in Erice (Italy) on 20 August. The prize is awarded each year by the WFS (World Federation of Scientists), whose president is Professor Antonino Zichichi, to a theoretical physicist for his outstanding contributions to particle physics. The selection committee is composed of eminent physicists and is chaired by the Nobel Physics Prize Laureate, T.D. Lee. André Martin was awarded the Medal in recognition of his work on the total cross-section for interactions between two particles and his contributions to the understanding of heavy quark-antiquark (or quarkonium) systems. In 1965, André Martin established a theoretical basis for the so-call...

  5. What physicists should learn about finance (if they want to)

    Science.gov (United States)

    Schmidt, Anatoly

    2006-03-01

    There has been growing interest among physicists to Econophysics, i.e. analysis and modeling of financial and economic processes using the concepts of theoretical Physics. There has been also perception that the financial industry is a viable alternative for those physicists who are not able or are not willing to pursue career in their major field. However in our times, the Wall Street expects from applicants for quantitative positions not only the knowledge of the stochastic calculus and the methods of time series analysis but also of such concepts as option pricing, portfolio management, and risk measurement. Here I describe a synthetic course based on my book ``Quantitative Finance for Physicists'' (Elsevier, 2004) that outlines both worlds: Econophysics and Mathematical Finance. This course may be offered as elective for senior undergraduate or graduate Physics majors.

  6. Great Physicists - The Life and Times of Leading Physicists from Galileo to Hawking

    Science.gov (United States)

    Cropper, William H.

    2004-09-01

    Here is a lively history of modern physics, as seen through the lives of thirty men and women from the pantheon of physics. William H. Cropper vividly portrays the life and accomplishments of such giants as Galileo and Isaac Newton, Marie Curie and Ernest Rutherford, Albert Einstein and Niels Bohr, right up to contemporary figures such as Richard Feynman, Murray Gell-Mann, and Stephen Hawking. We meet scientists--all geniuses--who could be gregarious, aloof, unpretentious, friendly, dogged, imperious, generous to colleagues or contentious rivals. As Cropper captures their personalities, he also offers vivid portraits of their great moments of discovery, their bitter feuds, their relations with family and friends, their religious beliefs and education. In addition, Cropper has grouped these biographies by discipline--mechanics, thermodynamics, particle physics, and others--each section beginning with a historical overview. Thus in the section on quantum mechanics, readers can see how the work of Max Planck influenced Niels Bohr, and how Bohr in turn influenced Werner Heisenberg. Our understanding of the physical world has increased dramatically in the last four centuries. With Great Physicists , readers can retrace the footsteps of the men and women who led the way.

  7. Clinical Training of Medical Physicists Specializing in Diagnostic Radiology

    International Nuclear Information System (INIS)

    2010-01-01

    The application of radiation in human health, for both diagnosis and treatment of disease, is an important component of the work of the IAEA. The responsibility for the increasing technical aspects of this work is undertaken by the medical physicist. To ensure good practice in this vital area, structured clinical training programmes are required to complement academic learning. This publication is intended to be a guide to the practical implementation of such a programme for diagnostic radiology. There is a general and growing awareness that radiation medicine is increasingly dependent on well trained medical physicists based in the clinical setting. However, an analysis of the availability of medical physicists indicates a large shortfall of qualified and capable professionals. This is particularly evident in developing countries. While strategies to increase academic educational opportunities are critical to such countries, the need for guidance on structured clinical training was recognized by the members of the Regional Cooperative Agreement (RCA) for Research, Development and Training related to Nuclear Sciences for Asia and the Pacific. Consequently, a technical cooperation regional project (RAS6038) under the RCA programme was formulated to address this need in the Asia-Pacific region by developing suitable material and establishing its viability. Development of a clinical training guide for medical physicists specializing in diagnostic radiology started in 2007 with the appointment of a core drafting committee of regional and international experts. The publication drew on the experiences of clinical training programmes in Australia and New Zealand, the UK and the USA, and was moderated by physicists working in the Asian region. This publication follows the approach of the IAEA publication Training Course Series No. 37, Clinical Training of Medical Physicists specializing in Radiation Oncology. This approach to clinical training has been successfully tested

  8. Towards a Uniform European Education for Medical Physicists

    International Nuclear Information System (INIS)

    Christofides, S.

    2008-01-01

    The European Federation of Organisations in Medical Physics (EFOMP) mission and objectives are briefly presented. The most attention is given to the education and training activities of the EFOMP. Revised EFOMP recommendations on Education, Training and CPD of Medical Physicists and Policy Statements are listed. In order for Medical Physics to be recognised by the European Union as a profession some future activities like Bologna Declaration process, continuous professional development, European Network for Medical Physics training Schools, actions for the harmonisation of the Education and Training of the Medical Physicist in Europe in accordance with EU Directive 2005/36/EC and EU Recommendation 2008/C 111/01 are also discussed

  9. A day with the women physicists of Pakistan

    Science.gov (United States)

    Hasnain, Aziz Fatima; Islam, Aquila; Ali, Asima; Qureshi, Riffat Mehmood; Qamar, Anisa

    2015-12-01

    The Working Group on Women in Physics successfully organized a national-level meeting of women physicists at the National Centre for Physics, Quaid-e-Azam University, to discuss the agenda for the 5th IUPAP International Conference on Women in Physics. This report describes the outcome of the meeting and the status of female physicists in Pakistan. It also includes a comparative study of the enrollment of women in undergraduate and graduate programs in physics, along with a brief description of factors that create hurdles for female students opting for higher education in this field.

  10. Tasks of physicists and graduated engineers in diagnostic radiology

    International Nuclear Information System (INIS)

    Angerstein, W.

    1987-01-01

    The tasks of physicists and engineers in diagnostic radiology are compiled and trends of development are discussed. Specific duties can be selected from these tasks for each department and physicist individually. An attempt is made to characterize the specific tasks of medical physics. The most important tasks are concerning subjects of (1) investment planning, (2) quality control and quality assurance, (3) service and maintenance, (4) radiation protection and electrical safety, (5) development, testing and adaption of equipment, (6) assistance in running the radiologic department, (7) research, (8) pre- and postgraduate training, (9) educational training, (10) miscellaneous. (author)

  11. Quietly Building Capabilities: New Instruments, Expertise, 'Quiet Wing' Available at DOE User Facility

    International Nuclear Information System (INIS)

    Lea, Alan S.; Kabius, Bernd C.; Arey, Bruce W.; Kovarik, Libor; Wang, Chong M.; Orr, Galya; Lyubinetsky, Igor; Carper, Ross R.

    2011-01-01

    This feature article is prepared for publication in Microscopy Today. The goal is to communicate the value of the Quiet Wing, EMSL's growing microscopy capability, and the science they enable to the microscopy community and hopefully various related research communities (e.g. catalysis, etc.). The secondary goals are to demonstrate EMSL's leadership in microscopy and show our DOE client we are making excellent use of ARRA and other investments. Although the last decade in electron microscopy has seen tremendous gains in image resolution, new challenges in the field have come to the forefront. First, new ultra-sensitive instruments bring about unprecedented environmental specifications and facility needs for their optimal use. Second, in the quest for higher spatial resolutions, the importance of developing and sharing crucial expertise-from sample preparation to scientific vision-has perhaps been deemphasized. Finally, for imaging to accelerate discoveries related to large scientific and societal problems, in situ capabilities that replicate real-world process conditions are often required to deliver necessary information. This decade, these are among the hurdles leaders in the field are striving to overcome.

  12. The importance of Radio Quiet Zone (RQZ) for radio astronomy

    Science.gov (United States)

    Umar, Roslan; Abidin, Zamri Zainal; Ibrahim, Zainol Abidin

    2013-05-01

    Most of radio observatories are located in isolated areas. Since radio sources from the universe is very weak, astronomer need to avoid radio frequency interference (RFI) from active spectrum users and radio noise produced by human made (telecommunication, mobile phone, microwave user and many more. There are many observatories around the world are surrounded by a Radio Quiet Zone (RQZ), which is it was set up using public or state laws. A Radio Quiet Zone normally consists of two areas: an exclusive area in which totally radio emissions are forbidden, with restrictions for residents and business developments, and a larger (radius up to 100 km above) coordination area where the power of radio transmission limits to threshold levels. Geographical Information System (GIS) can be used as a powerful tool in mapping large areas with varying RQZ profiles. In this paper, we report the initial testing of the usage of this system in order to identify the areas were suitable for Radio Quiet Zone. Among the important parameters used to develop the database for our GIS are population density, information on TV and telecommunication (mobile phones) transmitters, road networks (highway), and contour shielding. We will also use other information gathered from on-site RFI level measurements on selected 'best' areas generated by the GIS. The intention is to find the best site for the purpose of establishing first radio quiet zones for radio telescope in Malaysia.

  13. Modeling the Quiet Time Outflow Solution in the Polar Cap

    Science.gov (United States)

    Glocer, Alex

    2011-01-01

    We use the Polar Wind Outflow Model (PWOM) to study the geomagnetically quiet conditions in the polar cap during solar maximum, The PWOM solves the gyrotropic transport equations for O(+), H(+), and He(+) along several magnetic field lines in the polar region in order to reconstruct the full 3D solution. We directly compare our simulation results to the data based empirical model of Kitamura et al. [2011] of electron density, which is based on 63 months of Akebono satellite observations. The modeled ion and electron temperatures are also compared with a statistical compilation of quiet time data obtained by the EISCAT Svalbard Radar (ESR) and Intercosmos Satellites (Kitamura et al. [2011]). The data and model agree reasonably well. This study shows that photoelectrons play an important role in explaining the differences between sunlit and dark results, ion composition, as well as ion and electron temperatures of the quiet time polar wind solution. Moreover, these results provide validation of the PWOM's ability to model the quiet time ((background" solution.

  14. On the hazard of quiet vehicles to pedestrians and drivers.

    Science.gov (United States)

    Wogalter, Michael S; Lim, Raymond W; Nyeste, Patrick G

    2014-09-01

    The need to produce more efficient and less polluting vehicles has encouraged mass production of alternative energy vehicles, such as hybrid and electric cars. Many of these vehicles are capable of very quiet operation. While reducing noise pollution is desirable, quieter vehicles could negatively affect pedestrian safety because of reduced sound cues compared to louder internal combustion engines. Three studies were performed to investigate people's concern about this issue. In Study 1, a questionnaire completed by 378 people showed substantial positive interest in quiet hybrid and electric cars. However, they also indicated concern about the reduced auditory cues of quiet vehicles. In Study 2, 316 participants rated 14 sounds that could be potentially added to quiet alternative-energy vehicles. The data showed that participants did not want annoying sounds, but preferred adding "engine" and "hum" sounds relative to other types of sounds. In Study 3, 24 persons heard and rated 18 actual sounds within 6 categories that were added to a video of a hybrid vehicle driving by. The sounds most preferred were "engine" followed by "white noise" and "hum". Implications for adding sounds to facilitate pedestrians' detection of moving vehicles and for aiding drivers' awareness of speed are discussed. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  15. Occurrence and persistence of magnetic elements in the quiet Sun

    Science.gov (United States)

    Giannattasio, F.; Berrilli, F.; Consolini, G.; Del Moro, D.; Gošić, M.; Bellot Rubio, L.

    2018-03-01

    Context. Turbulent convection efficiently transports energy up to the solar photosphere, but its multi-scale nature and dynamic properties are still not fully understood. Several works in the literature have investigated the emergence of patterns of convective and magnetic nature in the quiet Sun at spatial and temporal scales from granular to global. Aims: To shed light on the scales of organisation at which turbulent convection operates, and its relationship with the magnetic flux therein, we studied characteristic spatial and temporal scales of magnetic features in the quiet Sun. Methods: Thanks to an unprecedented data set entirely enclosing a supergranule, occurrence and persistence analysis of magnetogram time series were used to detect spatial and long-lived temporal correlations in the quiet Sun and to investigate their nature. Results: A relation between occurrence and persistence representative for the quiet Sun was found. In particular, highly recurrent and persistent patterns were detected especially in the boundary of the supergranular cell. These are due to moving magnetic elements undergoing motion that behaves like a random walk together with longer decorrelations ( 2 h) with respect to regions inside the supergranule. In the vertices of the supegranular cell the maximum observed occurrence is not associated with the maximum persistence, suggesting that there are different dynamic regimes affecting the magnetic elements.

  16. Time and ageing: a physicist's look at gerontology

    NARCIS (Netherlands)

    Uffink, J.

    2000-01-01

    To enter, as a physicist, into the field of gerontology brings along certain dangers. I will presumably fall into pitfalls of misunderstanding or step on some other booby traps which those who are familiar with the terrain have learned to avoid. This danger is probably even greater since the

  17. Physicists see golden needle in a micro-cosmic haystack

    CERN Multimedia

    2004-01-01

    An international team of physicists examining an extremely rare form of subatomic particle decay has discovered evidence for the highly sought process, which could be an indication of new forces beyond those incorporated in the Standard Model of particle physics (1 page)

  18. Face to Face Tinker, Builder, Physicist, and Teacher !

    Indian Academy of Sciences (India)

    to science, highlighting the factors and circumstances that guided them in making the career choice to be a scientist. Tinker, Builder, Physicist, and .... Did you feel its influence on your environment in physics? MF: Stanford did want to bring ...

  19. Technical Training Seminar: Physicists in the world of finance

    CERN Multimedia

    Davide Vitè

    2006-01-01

    Monday 27 February TECHNICAL TRAINING SEMINAR from 14:00 to 16:00, Council Chamber (bldg. 503) Physicists in the world of finance Oliver Cooke, Zhengyun Hu / LEHMAN BROTHERS (UK) Two PhD physicists will talk about their experiences of working in investment banking, describing what investment banks do and the jobs which attract physicists and engineers. They will introduce the derivatives markets, and explain the need for advanced modelling. In particular, they will present the many modelling techniques used, including Monte Carlo simulation, solving PDEs, stochastic calculus and data analysis. They will describe a typical day for a physicist in the world of finance, and present a case study in which they will show how they used an idea from physics to solve a finance problem. After a PhD and CERN fellowship on OPAL in the 1990s, Oliver Cooke moved to finance. He was initially a mathematical modeller of derivatives, and now is an exotic derivatives trader at Lehman Brothers in London. He will be j...

  20. Review the Physicists show EVERYTHING happens at the same time

    DEFF Research Database (Denmark)

    javadi, Hossein; Forouzbakhsh, Farshid

    2016-01-01

    Physicist Max Tegmark claims flow of time is illusion. EVERYTHING happens at the same time, Max Tegmark said. [1] To understand how this theory is consistent with the truth, it should be compared with physical previous theories and experiences. The theory is backed up Einstein’s theory...

  1. Review the Physicists show EVERYTHING happens at the same time

    OpenAIRE

    javadi, Hossein; Forouzbakhsh, Farshid

    2016-01-01

    Physicist Max Tegmark claims flow of time is illusion. EVERYTHING happens at the same time, Max Tegmark said. [1] To understand how this theory is consistent with the truth, it should be compared with physical previous theories and experiences. The theory is backed up Einstein’s theory of relativity, Max Tegmark said. [1

  2. German lab unveils plan to build physicists' next collider

    CERN Multimedia

    Abott, A

    2001-01-01

    An international team of physicists are to propose the construction of a major collider. 'TESLA' - the 'Tera electron volt Energy Superconducting Linear Accelerator' will be a linear electron-positron collider based on superconducting resonators. It will be based at DESY and cost around three billion US dollars (2 pages).

  3. Proceedings of the 2. Brazilian Congress of Physicists on Medicine

    International Nuclear Information System (INIS)

    1987-01-01

    The works of the 2. Brazilian Congress of Physicists on Medicine are presented, including course of 'Tomography by Nuclear Magnetic Resonance' and 'New Techniques in the Physics of X Ray Diagnostic' and topics about radiotherapy, radiodiagnostic and dosimetry. (C.G.C.) [pt

  4. Education and training of hospital physicists in Sweden

    International Nuclear Information System (INIS)

    Walstam, R.

    1974-01-01

    The Swedish programme for educating hospital physicists differs from many others by introducing radiation physics at the undergraduate level and requiring an extensive in-service training. In view of the rapid growth of the profession this is considered valuable. The present educational capacity has caused noticeable competition and it is generally necessary to have much higher qualifications than the minimum requirements. (JIW)

  5. "Angels & Demons" May Help Physicists Explain What Matters

    Science.gov (United States)

    Basken, Paul

    2009-01-01

    It's not every day that scientific researchers need to defend themselves against charges of destroying humanity. And yet a group of several dozen physicists associated with the Large Hadron Collider may be getting pretty good at it--and, at the same time, actively engaging in public education and debate in ways that university scientists have…

  6. Proceedings of the school for young high energy physicists

    International Nuclear Information System (INIS)

    McCubbin, N.A.

    1988-01-01

    The paper concerns the Proceedings of the 'School for Young High Energy Physicists', which was held at the Rutherford Appleton Laboratory, Sept. 1987. The lectures were presented in four courses, and were intended to give experimentalists a grounding in Relativistic Quantum Field Theory. The four lectures courses were each selected for INIS and indexed separately. (U.K.)

  7. ENSDF: a nuclear structure data bank for nuclear physicists

    International Nuclear Information System (INIS)

    Blachot, J.

    1987-02-01

    Data Banks have tremendously grown these last years. All the nuclear Structure information are now in the ENSDF. This file is used for the Nuclear Data Sheets publication. The part which contains only Adopted Data could be used as a Data Bank for Nuclear Physicists. Examples of retrevial are given [fr

  8. Physics, Physicists and Revolutionary Capabilities for the Intelligence Community

    Science.gov (United States)

    Porter, Lisa

    2009-05-01

    Over the past several decades, physicists have made seminal contributions to technological capabilities that have enabled the U.S. intelligence community to provide unexpected and unparalleled information to our nation's decision makers and help dispel the cloud of uncertainty they face in dealing with crises and challenges around the world. As we look to the future, we recognize that the ever-quickening pace of changes in the world and the threats we must confront demand continued innovation and improvement in the capabilities needed to provide the information on which our leaders depend. This talk will focus on some of the major technological challenges that the intelligence community faces in the coming years, and the many ways that physicists can help to overcome those challenges. The potential impact of physicists on the future capabilities of the US intelligence community is huge. In addition to the more obvious and direct impact through research in areas ranging from novel sensors to quantum information science, the unique approach physicists bring to a problem can also have an indirect but important effect by influencing how challenges in areas ranging from cybersecurity to advanced analytics are approached and solved. Several examples will be given.

  9. Education and Training of Medical Physicists in Europe

    Directory of Open Access Journals (Sweden)

    P. A. Kaplanis

    2008-01-01

    Full Text Available Introduction: Medical Physicist, as a professional who works in a hospital environment, is a member of a wide clinical team which is responsible for the correct diagnosis and the therapeutic methods applied using radiation. The role of a Medical Physicist is multifold and consists of the estimation of the dose received by patients and personnel, the quality control of radiological equipment, the studies for shielding requirements and the training of several health professionals (doctors, medical physicists, radiologists, technicians, nurses. All the above are prerequisites in order to receive the professional license to act as Medical Physicist.Aim-Research Inquires: The aim of European Union (EU via European Federation of Medical Physics (EFOMP is to apply a common policy among the EU countries in the area of Education and Training in Medical Physics within the context of the current developments in the European Higher Education Area arising from “The Bologna Declaration”. A short-term perspective is the free movement of professionals within EU, via the assurance of knowledge and skills uniformity. A necessary preliminary stage is the collection, classification and further process of relevant information at the European level.Methods-Techniques: To achieve the above in an efficient way EFOMP prepared a questionnaire and sent it to the National Organisation for Medical Physics of each country member of EFOMP (NMO. 23 out of 34 country members responded. The main parts (3 in total of this questionnaire and some typical questions were:Part A: Medical Physics Education•Which degree is required? Is this a university degree? How many years of studies does it represent?•Is there a nationally approved education programme and, if yes, then by whom?•Where do the education and training take place (University, Hospital, or both of them? Are these centers accredited and who gives the accreditation?Part B: Qualified / Specialist Medical Physicist

  10. 49 CFR Appendix C to Part 222 - Guide to Establishing Quiet Zones

    Science.gov (United States)

    2010-10-01

    ... authority. FRA believes that it will be very useful to include these organizations in the planning process... implementation process. This section also discusses Partial (e.g. night time only quiet zones) and Intermediate... provides four basic ways in which a quiet zone may be established. Creation of both New Quiet Zones and Pre...

  11. Recruitment of quiet cells at the onset of vasomotion in mesenteric arteries

    DEFF Research Database (Denmark)

    Brings Jacobsen, Jens Christian; Aalkjær, Christian; Matchkov, Vladimir

    2008-01-01

    quiet. At the onset of vasomotion however, all cells, including those that were previously quiet, are forced into synchronized oscillation. We hypothesize that this entrainment of previously quiet cells is caused by the driving force from a collective cyclic variation in membrane potential.   Methods...

  12. Clinical Training of Medical Physicists Specializing in Radiation Oncology

    International Nuclear Information System (INIS)

    2009-01-01

    The application of radiation in human health, for both diagnosis and treatment of disease, is an important component of the work of the IAEA. The responsibility for the increasing technical aspects of this work is undertaken by the medical physicist. To ensure good practice in this vital area structured clinical training programmes are required to complement academic learning. This publication is intended to be a guide to the practical implementation of such a programme for radiation therapy. There is a general and growing awareness that radiation medicine is increasingly dependant on well trained medical physicists that are based in the clinical setting. However an analysis of the availability of medical physicists indicates a large shortfall of qualified and capable professionals. This is particularly evident in developing countries. While strategies to increase academic educational opportunities are critical to such countries, the need for guidance on structured clinical training was recognised by the members of the Regional Cooperative Agreement (RCA) for research, development and training related to nuclear sciences for Asia and the Pacific. Consequently a technical cooperation regional project (RAS6038) under the RCA programme was formulated to address this need in the Asia Pacific region by developing suitable material and establishing its viability. Development of a clinical training guide for medical physicists specialising in radiation therapy was started in 2005 with the appointment of a core drafting committee of regional and international experts. Since 2005 the IAEA has convened two additional consultant group meetings including additional experts to prepare the present publication. The publication drew heavily, particularly in the initial stages, from the experience and documents of the Clinical Training Programme for Radiation Oncology Medical Physicists as developed by the Australasian College of Physical Scientists and Engineers in Medicine. Their

  13. The role of the health physicist in nuclear security.

    Science.gov (United States)

    Waller, Edward J; van Maanen, Jim

    2015-04-01

    Health physics is a recognized safety function in the holistic context of the protection of workers, members of the public, and the environment against the hazardous effects of ionizing radiation, often generically designated as radiation protection. The role of the health physicist as protector dates back to the Manhattan Project. Nuclear security is the prevention and detection of, and response to, criminal or intentional unauthorized acts involving or directed at nuclear material, other radioactive material, associated facilities, or associated activities. Its importance has become more visible and pronounced in the post 9/11 environment, and it has a shared purpose with health physics in the context of protection of workers, members of the public, and the environment. However, the duties and responsibilities of the health physicist in the nuclear security domain are neither clearly defined nor recognized, while a fundamental understanding of nuclear phenomena in general, nuclear or other radioactive material specifically, and the potential hazards related to them is required for threat assessment, protection, and risk management. Furthermore, given the unique skills and attributes of professional health physicists, it is argued that the role of the health physicist should encompass all aspects of nuclear security, ranging from input in the development to implementation and execution of an efficient and effective nuclear security regime. As such, health physicists should transcend their current typical role as consultants in nuclear security issues and become fully integrated and recognized experts in the nuclear security domain and decision making process. Issues regarding the security clearances of health physics personnel and the possibility of insider threats must be addressed in the same manner as for other trusted individuals; however, the net gain from recognizing and integrating health physics expertise in all levels of a nuclear security regime far

  14. Modular trigger processing The GCT muon and quiet bit system

    CERN Document Server

    Stettler, Matthew; Hansen, Magnus; Iles, Gregory; Jones, John; PH-EP

    2007-01-01

    The CMS Global Calorimeter Trigger system's HCAL Muon and Quiet bit reformatting function is being implemented with a novel processing architecture. This architecture utilizes micro TCA, a modern modular communications standard based on high speed serial links, to implement a processing matrix. This matrix is configurable in both logical functionality and data flow, allowing far greater flexibility than current trigger processing systems. In addition, the modular nature of this architecture allows flexibility in scale unmatched by traditional approaches. The Muon and Quiet bit system consists of two major components, a custom micro TCA backplane and processing module. These components are based on Xilinx Virtex5 and Mindspeed crosspoint switch devices, bringing together state of the art FPGA based processing and Telcom switching technologies.

  15. Quantitative Global Heat Transfer in a Mach-6 Quiet Tunnel

    Science.gov (United States)

    Sullivan, John P.; Schneider, Steven P.; Liu, Tianshu; Rubal, Justin; Ward, Chris; Dussling, Joseph; Rice, Cody; Foley, Ryan; Cai, Zeimin; Wang, Bo; hide

    2012-01-01

    This project developed quantitative methods for obtaining heat transfer from temperature sensitive paint (TSP) measurements in the Mach-6 quiet tunnel at Purdue, which is a Ludwieg tube with a downstream valve, moderately-short flow duration and low levels of heat transfer. Previous difficulties with inferring heat transfer from TSP in the Mach-6 quiet tunnel were traced to (1) the large transient heat transfer that occurs during the unusually long tunnel startup and shutdown, (2) the non-uniform thickness of the insulating coating, (3) inconsistencies and imperfections in the painting process and (4) the low levels of heat transfer observed on slender models at typical stagnation temperatures near 430K. Repeated measurements were conducted on 7 degree-half-angle sharp circular cones at zero angle of attack in order to evaluate the techniques, isolate the problems and identify solutions. An attempt at developing a two-color TSP method is also summarized.

  16. Digital control and data acquisition system for the QUIET experiment

    International Nuclear Information System (INIS)

    Bogdan, Mircea; Kapner, Dan; Samtleben, Dorothea; Vanderlinde, Keith

    2007-01-01

    We present the Digital Control and Data Acquisition System (DCDAQ) for Phase I of the Q/U Imaging Experiment (QUIET), arrays of 91 W-band and 19 Q-band receivers, placed on 1.4 m telescopes, in Chajnantor, Chile to measure the polarization of the cosmic microwave background. QUIET uses custom-built electronics boards that control and monitor its polarimeters. Each of these boards is digitally addressable, so that the DCDAQ can set and monitor any of the 1600 biases needed to operate the 91 receivers. The DCDAQ consists of a controller and up to 13 custom-made 32-channel ADC cards. Local FPGAs allow real-time data processing for each channel. This immediate data reduction is necessary, as it is planned to scale this technology beyond Phase I. The DCDAQ system is implemented with this future in mind and can easily be scaled to operate 1000 receivers

  17. No evidence for radio-quiet BL Lacertae objects

    International Nuclear Information System (INIS)

    Stocke, J.T.; Morris, S.L.; Gioia, I.; Maccacaro, T.; Schild, R.E.

    1990-01-01

    Using a large, flux-limited sample of faint X-ray sources, a search has been conducted for radio-quiet BL Lacertae objects. None has been found. Thirty-two X-ray-selected BL Lac objects and BL Lac candidates have been found within the sources of the Einstein Medium Sensitivity Survey (EMSS). Thirty-one of these have been observed with the VLA and all have been detected at 5 GHz. While the optical magnitudes of the EMSS BL Lac objects range from 17 to 20.8, their radio-to-optical spectral indices occupy a very small range. The very bright X-ray-selected BL Lac objects like PKS 2155-304 and Markarian 501 have similar range values. Therefore, unlike the clear dichotomy between radio-loud quasars and radio-quiet QSOs, there is no evidence for two populations of Lacertids distinguished by radio loudness. 43 refs

  18. Atlantic: market quiet, utilities well stocked and war clouds gather...

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-02-01

    Most observers feel the 2003 outlook for coal demand in Europe will remain both quiet and unsettled until an outcome is reached in the current stand-off in the UN with regard to the disarming of Iraq. The situation in Venezuela remains uncertain due to the strike and as a result Colombian exporters have made spot sales to US utilities. One positive development is the decision by ENDESA to convert its Italian Fiume Santo plant to coal. 3 photos.

  19. Quiet sustainability: Fertile lessons from Europe's productive gardeners

    Czech Academy of Sciences Publication Activity Database

    Smith, J.; Jehlička, Petr

    2013-01-01

    Roč. 32, č. 3 (2013), s. 148-157 ISSN 0743-0167 R&D Projects: GA ČR GAP404/10/0521 Institutional research plan: CEZ:AV0Z70280505 Keywords : Quiet sustainability * Sustainable development * Sharing Subject RIV: AD - Politology ; Political Sciences Impact factor: 2.036, year: 2013 http://www.sciencedirect.com/science/article/pii/S0743016713000454

  20. Dark Skies are a Universal Resource. So are Quiet Skies!

    Science.gov (United States)

    Maddalena, Ronald J.; Heatherly, S.

    2008-05-01

    You've just purchased your first telescope. But where to set it up? Certainly not a WalMart parking lot. Too much light pollution! In the same way that man-made light obscures our night sky and blinds ground-based optical telescopes, man-made radio signals blind radio telescopes as well. NRAO developed the Quiet Skies project to increase awareness of radio frequency interference (RFI) and radio astronomy in general by engaging students in local studies of RFI. To do that we created a sensitive detector which measures RFI. We produced 20 of these, and assembled kits containing detectors and supplementary materials for loan to schools. Students conduct experiments to measure the properties of RFI in their area, and input their measurements into a web-based data base. The Quiet Skies project is a perfect complement to the IYA Dark Skies Awareness initiative. We hope to place 500 Quiet Skies detectors into the field through outreach to museums and schools around the world. Should we be successful, we will sustain this global initiative via a continuing loan program. One day we hope to have a publicly generated image of the Earth which shows RFI much as the Earth at Night image illustrates light pollution. The poster will present the components of the project in detail, including our plans for IYA, and various low-cost alternative strategies for introducing RFI and radio astronomy to the public. We will share the results of some of the experiments already being performed by high school students. Development of the Quiet Skies project was funded by a NASA IDEAS grant. The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

  1. Fractional derivatives for physicists and engineers background and theory

    CERN Document Server

    Uchaikin, Vladimir V

    2013-01-01

    The first derivative of a particle coordinate means its velocity, the second means its acceleration, but what does a fractional order derivative mean? Where does it come from, how does it work, where does it lead to? The two-volume book written on high didactic level answers these questions. Fractional Derivatives for Physicists and Engineers— The first volume contains a clear introduction into such a modern branch of analysis as the fractional calculus. The second develops a wide panorama of applications of the fractional calculus to various physical problems. This book recovers new perspectives in front of the reader dealing with turbulence and semiconductors, plasma and thermodynamics, mechanics and quantum optics, nanophysics and astrophysics.  The book is addressed to students, engineers and physicists, specialists in theory of probability and statistics, in mathematical modeling and numerical simulations, to everybody who doesn't wish to stay apart from the new mathematical methods becoming more and ...

  2. First results on quiet and magnetic granulation from SOUP

    Science.gov (United States)

    Title, A. M.; Tarbell, T. D.; Acton, L.; Duncan, D.; Ferguson, S. H.; Finch, M.; Frank, Z.; Kelly, G.; Lindgren, R.; Morrill, M.

    1987-01-01

    The flight of Solar Optical Universal Polarimeter (SOUP) on Spacelab 2 allowed the collection of time sequences of diffraction limited (0.5 arc sec) granulation images with excellent pointing (0.003 arc sec) and completely free of the distortion that plagues groundbased images. The p-mode oscillations are clearly seen in the data. Using Fourier transforms in the temporal and spatial domain, it was shown that the p-modes dominate the autocorrelation lifetime in magnetic regions. When these oscillations are removed the autocorrelation lifetime is found to be 500 sec in quiet and 950 sec in magnetic regions. In quiet areas exploding granules are seen to be common. It is speculated that a significant fraction of granule lifetimes are terminated by nearby explosions. Using local correlation tracking techniques it was able to measure horizontal displacements, and thus transverse velocities, in the magnetic field. In quiet sun it is possible to detect both super and mesogranulation. Horizontal velocities are as great as 1000 m/s and the average velocity is 400 m/s. In magnetic regions horizontal velocities are much less, about 100 m/s.

  3. Small-scale eruptive filaments on the quiet sun

    International Nuclear Information System (INIS)

    Hermans, L.M.; Martin, S.F.

    1986-01-01

    A study of a little known class of eruptive events on the quiet sun was conducted. All of 61 small-scale eruptive filamentary structures were identified in a systematic survey of 32 days of H alpha time-lapse films of the quiet sun acquired at Big Bear Solar Observatory. When fully developed, these structures have an average length of 15 arc seconds before eruption. They appear to be the small-scale analog of large-scale eruptive filaments observed against the disk. At the observed rate of 1.9 small-scale eruptive features per field of view per average 7.0 hour day, the rate of occurence of these events on the sun were estimated to be greater than 600 per 24 hour day.. The average duration of the eruptive phase was 26 minutes while the average lifetime from formation through eruption was 70 minutes. A majority of the small-scale filamentary sturctures were spatially related to cancelling magnetic features in line-of-sight photospheric magnetograms. Similar to large-scale filaments, the small-scale filamentary structures sometimes divided opposite polarity cancelling fragments but often had one or both ends terminating at a cancellation site. Their high numbers appear to reflect the much greater flux on the quiet sun. From their characteristics, evolution, and relationship to photospheric magnetic flux, it was concluded that the structures described are small-scale eruptive filaments and are a subset of all filaments

  4. On the quiet-time Pc 5 pulsation events (spacequakes)

    International Nuclear Information System (INIS)

    Gupta, J.C.; Niblett, E.R.

    1979-01-01

    A quiet-time Pc 5 event (designated Spacequake) of March 18, 1974, first noted on the Fort Churchill magnetogram, was studied using global data. Its amplitude was found to be largest in the northern part of the auroral zone and its period seemed to increase with latitude. The clockwise polarization of the event noted at Baker Lake and higher latitudes changed to counterclockwise at Fort Churchill in X-Y, X-Z and Y-Z planes. The resonance of a field line (L approximately 10) excited due to an instability of the Kelvin-Helmholtz type may have given rise to the observed event. It is conjectured that the cause of instability at this altitude was internal convection of the magnetosphere. Similar quiet-time events from four Canadian observatories were selected from approximately 11 years of magnetograms and their statistical analysis revealed that (i) occurrences maximised near dawn and dusk (ii) the amplitude-latitude profile peaked at Great Whale River (L approximately 6.67), (iii) periods increased with increasing geomagnetic latitudes, (iv) a large number of events occurred in January, February and March every year, and (v) frequency of occurrence increased with increasing sunspot numbers. Comparison of these results with those available in the literature from analyses of satellite data clearly indicate that quiet-time Pc 5 events (Spacequakes) originate in the outer magnetosphere. (author)

  5. Energy Input Flux in the Global Quiet-Sun Corona

    Energy Technology Data Exchange (ETDEWEB)

    Mac Cormack, Cecilia; Vásquez, Alberto M.; López Fuentes, Marcelo; Nuevo, Federico A. [Instituto de Astronomía y Física del Espacio (IAFE), CONICET-UBA, CC 67—Suc 28, (C1428ZAA) Ciudad Autónoma de Buenos Aires (Argentina); Landi, Enrico; Frazin, Richard A. [Department of Climate and Space Sciences and Engineering (CLaSP), University of Michigan, 2455 Hayward Street, Ann Arbor, MI 48109-2143 (United States)

    2017-07-01

    We present first results of a novel technique that provides, for the first time, constraints on the energy input flux at the coronal base ( r ∼ 1.025 R {sub ⊙}) of the quiet Sun at a global scale. By combining differential emission measure tomography of EUV images, with global models of the coronal magnetic field, we estimate the energy input flux at the coronal base that is required to maintain thermodynamically stable structures. The technique is described in detail and first applied to data provided by the Extreme Ultraviolet Imager instrument, on board the Solar TErrestrial RElations Observatory mission, and the Atmospheric Imaging Assembly instrument, on board the Solar Dynamics Observatory mission, for two solar rotations with different levels of activity. Our analysis indicates that the typical energy input flux at the coronal base of magnetic loops in the quiet Sun is in the range ∼0.5–2.0 × 10{sup 5} (erg s{sup −1} cm{sup −2}), depending on the structure size and level of activity. A large fraction of this energy input, or even its totality, could be accounted for by Alfvén waves, as shown by recent independent observational estimates derived from determinations of the non-thermal broadening of spectral lines in the coronal base of quiet-Sun regions. This new tomography product will be useful for the validation of coronal heating models in magnetohydrodinamic simulations of the global corona.

  6. First results on quiet and magnetic granulation from SOUP

    Science.gov (United States)

    Title, A. M.; Tarbell, T. D.; Acton, L.; Duncan, D.; Ferguson, S. H.; Finch, M.; Frank, Z.; Kelly, G.; Lindgren, R.; Morrill, M.

    1987-09-01

    The flight of Solar Optical Universal Polarimeter (SOUP) on Spacelab 2 allowed the collection of time sequences of diffraction limited (0.5 arc sec) granulation images with excellent pointing (0.003 arc sec) and completely free of the distortion that plagues groundbased images. The p-mode oscillations are clearly seen in the data. Using Fourier transforms in the temporal and spatial domain, it was shown that the p-modes dominate the autocorrelation lifetime in magnetic regions. When these oscillations are removed the autocorrelation lifetime is found to be 500 sec in quiet and 950 sec in magnetic regions. In quiet areas exploding granules are seen to be common. It is speculated that a significant fraction of granule lifetimes are terminated by nearby explosions. Using local correlation tracking techniques it was able to measure horizontal displacements, and thus transverse velocities, in the magnetic field. In quiet sun it is possible to detect both super and mesogranulation. Horizontal velocities are as great as 1000 m/s and the average velocity is 400 m/s. In magnetic regions horizontal velocities are much less, about 100 m/s.

  7. The EUV chromospheric network in the quiet Sun

    International Nuclear Information System (INIS)

    Reeves, E.M.

    1976-01-01

    Investigations on the structure and intensity of the chromospheric network from quiet solar regions have been carried out with EUV data obtained from the Harvard spectroheliometer on the Apollo Telescope Mount of Skylab. The distribution of intensities within supergranulation cell interiors follows a near normal function, where the standard deviation exceeds the value expected from the counting rate, which indicates fine-scale structure below the 5 arc sec resolution of the data. The intensities from the centers of supergranulation cells appear to be the same in both quiet regions and coronal holes, although the network is significantly different in the two types of regions. The average halfwidth of the network elements was measured as 10 arc sec, and was independent of the temperature of formation of the observing line for 3.8< logTsub(e)<5.8. The contrast between the network and the centers of cells is greatest for lines with logTsub(e)approximately5.2, where the network contributes approximately 75% of the intensity of quiet solar regions. The contrast and fractional intensity contributions decrease to higher and lower temperatures characteristic of the corona and chromosphere. (Auth.)

  8. Niels Bohr. Physicist and philospher of the atomic era

    International Nuclear Information System (INIS)

    Fischer, Ernst Peter

    2012-01-01

    The physicist and Nobel-prize carrier Niels Bohr (1885-1962) changed by his research our view to the world. By his atomic model for the first time the stability of matter could be explained, but simultaneously the atomic physics and nuclear technique based on this made our world so dangerous as never before. In an impressive portrait Ernst Peter Fischer describes the life and action of this fascinating man, his great physical finding, as well as his political engagement.

  9. Uncertain CERN cash means UK physicists face grant freeze.

    CERN Document Server

    1996-01-01

    Britain's funding agency Particle Physics and Astronomy Research Council is uncertain about its ability to cover membership costs to the European Laboratory for Particle Physics (CERN). This has resulted in suspension of research grants to university physicists and astronomers. Funding will be available only for genuine hardship, and for major national and international astronomical projects that have already been sanctioned. The new four-year rolling grants to university-based particle physics group is withheld.

  10. Physicists and Economic Growth: Preparing the Next Generation

    Science.gov (United States)

    Arion, Douglas

    2012-02-01

    For many years it has been recognized that many physicists are ``hidden'' -- deep in the industrial world or holding positions not named ``physicist.'' In parallel with this phenomenon is the recognition that many new and innovative product ideas are, in fact, generated by physicists. There are many more ideas that could be brought to market to the benefit of both society and the inventor, but physicists don't often see themselves as the innovators and inventors that they actually are. A number of education programs have arisen to try to address this issue and to engender a greater entrepreneurial spirit in the scientific community. The ScienceWorks program at Carthage College was one of the first to do so, and has for nearly twenty years prepared undergraduate science majors to understand and practice innovation and value creation. Other programs, such as professional masters degrees, also serve to bridge the technical and business universes. As it is no doubt easier to teach a scientist the world of business than it is to teach a businessperson the world of physics, providing educational experiences in innovation and commercialization to physics students can have tremendous economic impact, and will also better prepare them for whatever career direction they may ultimately pursue, even if it is the traditional tenure-track university position. This talk will discuss education programs that have been effective at preparing physics students for the professional work environment, and some of the positive outcomes that have resulted. Also discussed will be the variety of opportunities and resources that exist for faculty and students to develop the skills, knowledge and abilities to recognize and successfully commercialize innovations.

  11. OBITUARY: Sir William Mitchell Physicist and enthusiast for science

    CERN Multimedia

    Cowley, R

    2002-01-01

    "William Mitchell was successively head of Physics at Reading and Oxford universities, and Chairman of the Science and Engineering Research Council from 1985 to 1990. He is largely responsible for the excellent neutron and X-ray facilities that are available for research by scientists in the UK. He was one of the first to realise that these uniquely powerful facilities would be essential tools not only for physicists but also for chemists, biologists, materials scientists and engineers" (1 page).

  12. The duty health physicist program at Byron Nuclear Power Station

    International Nuclear Information System (INIS)

    Goldsmith, D.G.; Carey, T.R.

    1987-01-01

    The Duty Health Physicist Program at Byron Station was established to deal with routine health physics tasks and provide an interface between frontline and upper radiation-chemistry management. The program consists of a weekly rotation of selected members of the health physics staff into the duty health physicist position to handle the assigned duty tasks. The tasks include, but are not limited to, daily isotopic and air sample review, effluent release package review, maximum permissible concentration calculations, dose approvals, as-low-as-reasonably-achievable action review of pending jobs, and general availability to answer questions and address problems in health-physics-related areas of plant operation. The daily attendance of the duty health physicist at the radiation-chemistry and station plan-of-the-day meetings has increased the overall presence and visibility of the health physics program to upper station management and other station departments. Since its inception in July of 1985, the Duty Health Physics Program has been a major contributor to the observed 50% reduction in reportable personnel errors in the radiation-chemistry department (based on personnel-error-related deviation reports and license event reports generated on the radiation-chemistry department at Byron Station). Although difficulty to quantify, other important benefits of this program are also discussed in this paper

  13. 49 CFR 222.41 - How does this rule affect Pre-Rule Quiet Zones and Pre-Rule Partial Quiet Zones?

    Science.gov (United States)

    2010-10-01

    ...-Rule Quiet Zone may be established by automatic approval and remain in effect, subject to § 222.51, if... Zone may be established by automatic approval and remain in effect, subject to § 222.51, if the Pre... 49 Transportation 4 2010-10-01 2010-10-01 false How does this rule affect Pre-Rule Quiet Zones and...

  14. The current status of education and career paths of students after completion of medical physicist programs in Japan: a survey by the Japanese Board for Medical Physicist Qualification.

    Science.gov (United States)

    Kadoya, Noriyuki; Karasawa, Kumiko; Sumida, Iori; Arimura, Hidetaka; Yamada, Syogo

    2015-07-01

    To standardize educational programs and clinical training for medical physics students, the Japanese Board for Medical Physicist Qualification (JBMP) began to accredit master's, doctorate, and residency programs for medical physicists in 2012. At present, 16 universities accredited by the JBMP offer 22 courses. In this study, we aimed to survey the current status of educational programs and career paths of students after completion of the medical physicist program in Japan. A questionnaire was sent in August 2014 to 32 universities offering medical physicist programs. The questionnaire was created and organized by the educational course certification committee of the JBMP and comprised two sections: the first collected information about the university attended, and the second collected information about characteristics and career paths of students after completion of medical physicist programs from 2008 to 2014. Thirty universities (16 accredited and 14 non-accredited) completed the survey (response rate 94 %). A total of 209, 40, and 3 students graduated from the master's, doctorate, and residency programs, respectively. Undergraduates entered the medical physicist program constantly, indicating an interest in medical physics among undergraduates. A large percentage of the students held a bachelor's degree in radiological technology (master's program 94 %; doctorate program 70 %); graduates obtained a national radiological technologist license. Regarding career paths, although the number of the graduates who work as medical physicist remains low, 7 % with a master's degree and 50 % with a doctorate degree worked as medical physicists. Our results could be helpful for improving the medical physicist program in Japan.

  15. Sensor-Based Inspection of the Formation Accuracy in Ultra-Precision Grinding (UPG) of Aspheric Surface Considering the Chatter Vibration

    Science.gov (United States)

    Lei, Yao; Bai, Yue; Xu, Zhijun

    2018-06-01

    This paper proposes an experimental approach for monitoring and inspection of the formation accuracy in ultra-precision grinding (UPG) with respect to the chatter vibration. Two factors related to the grinding progress, the grinding speed of grinding wheel and spindle, and the oil pressure of the hydrostatic bearing are taken into account to determining the accuracy. In the meantime, a mathematical model of the radius deviation caused by the micro vibration is also established and applied in the experiments. The results show that the accuracy is sensitive to the vibration and the forming accuracy is much improved with proper processing parameters. It is found that the accuracy of aspheric surface can be less than 4 μm when the grinding speed is 1400 r/min and the wheel speed is 100 r/min with the oil pressure being 1.1 MPa.

  16. Sensor-Based Inspection of the Formation Accuracy in Ultra-Precision Grinding (UPG) of Aspheric Surface Considering the Chatter Vibration

    Science.gov (United States)

    Lei, Yao; Bai, Yue; Xu, Zhijun

    2018-03-01

    This paper proposes an experimental approach for monitoring and inspection of the formation accuracy in ultra-precision grinding (UPG) with respect to the chatter vibration. Two factors related to the grinding progress, the grinding speed of grinding wheel and spindle, and the oil pressure of the hydrostatic bearing are taken into account to determining the accuracy. In the meantime, a mathematical model of the radius deviation caused by the micro vibration is also established and applied in the experiments. The results show that the accuracy is sensitive to the vibration and the forming accuracy is much improved with proper processing parameters. It is found that the accuracy of aspheric surface can be less than 4 μm when the grinding speed is 1400 r/min and the wheel speed is 100 r/min with the oil pressure being 1.1 MPa.

  17. WHAT IS THE SOURCE OF QUIET SUN TRANSITION REGION EMISSION?

    Energy Technology Data Exchange (ETDEWEB)

    Schmit, D. J.; De Pontieu, Bart [Lockheed-Martin Solar and Astrophysics Laboratory, Palo Alto, CA 94304 (United States)

    2016-11-10

    Dating back to the first observations of the on-disk corona, there has been a qualitative link between the photosphere’s magnetic network and enhanced transition-temperature plasma emission. These observations led to the development of a general model that describes emission structures through the partitioning of the atmospheric volume with different magnetic loop geometries that exhibit different energetic equilibria. Does the internetwork produce transition-temperature emission? What fraction of network flux connects to the corona? How does quiet Sun emission compare with low-activity Sun-like stars? In this work, we revisit the canonical model of the quiet Sun, with high-resolution observations from the Interface Region Imaging Spectrograph ( IRIS ) and HMI in hand, to address those questions. We use over 900 deep exposures of Si iv 1393 Å from IRIS along with nearly simultaneous HMI magnetograms to quantify the correlation between transition-temperature emission structures and magnetic field concentrations through a number of novel statistics. Our observational results are coupled with analysis of the Bifrost MHD model and a large-scale potential field model. Our results paint a complex portrait of the quiet Sun. We measure an emission signature in the distant internetwork that cannot be attributed to network contribution. We find that the dimmest regions of emission are not linked to the local vertical magnetic field. Using the MHD simulation, we categorize the emission contribution from cool mid-altitude loops and high-altitude coronal loops and discuss the potential emission contribution of spicules. Our results provide new constraints on the coupled solar atmosphere so that we can build on our understanding of how dynamic thermal and magnetic structures generate the observed phenomena in the transition region.

  18. Doing physics how physicists take hold of the world

    CERN Document Server

    Krieger, Martin H

    2012-01-01

    Doing Physics makes concepts of physics easier to grasp by relating them to everyday knowledge. Addressing some of the models and metaphors that physicists use to explain the physical world, Martin H. Krieger describes the conceptual world of physics by means of analogies to economics, anthropology, theater, carpentry, mechanisms such as clockworks, and machine tool design. The interaction of elementary particles or chemical species, for example, can be related to the theory of kinship-who can marry whom is like what can interact with what. Likewise, the description of physical situations i

  19. Labor Market Trends for Health Physicists through 2005

    International Nuclear Information System (INIS)

    1997-10-01

    This report reviews past, current, and projected future labor market trends for health physicists through 2005. Information is provided on degrees granted, available supply of new graduates, employment, job openings for new graduates, and salaries. Job openings for new graduates are compared to the available supply of new graduates to assess relative job opportunities in the health physics labor market. The report is divided into three sections: trends during 1983-1993, trends during the mid-1990s, and projected trends for 1997 through 2005

  20. Beller Lecture: Dialogue Across Divides - Physicists and the Iran Dossier

    Science.gov (United States)

    Neuneck, Götz

    For over a decade, the nuclear activities of the Islamic Republic of Iran have been at the center of international concerns and subsequent track II talks. NGOs, think tanks and analysts played a role to help to find technical solutions in a highly political setting. The talk will give an overview about the role of physicists to understand the Iranian sensitive nuclear fuel-cycle and to prepare the ground for the JCPOA. Furthermore, the experience of the work of the Pugwash Conferences on Science and World Affairs will be elaborated.

  1. Julian Schwinger the physicist, the teacher, and the man

    CERN Document Server

    1996-01-01

    In the post-quantum-mechanics era, few physicists, if any, have matched Julian Schwinger in contributions to and influence on the development of physics. A deep and provocative thinker, Schwinger left his indelible mark on all areas of theoretical physics; an eloquent lecturer and immensely successful mentor, he was gentle, intensely private, and known for being "modest about everything except his physics". This book is a collection of talks in memory of him by some of his contemporaries and his former students: A Klein, F Dyson, B DeWitt, W Kohn, D Saxon, P C Martin, K Johnson, S Deser, R Fin

  2. Snowmass 2013 Young Physicists Science and Career Survey Report

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, J. [Fermilab; Asaadi, J. [Syracuse U.; Carls, B. [Fermilab; Cotta, R. [UC, Irvine; Guenette, R. [Yale U.; Kiburg, B. [Fermilab; Kobach, A. [Northwestern U.; Lippincott, H. [Fermilab; Littlejohn, B. [Cincinnati U.; Love, J. [Argonne; Penning, B. [Fermilab; Santos, M. Soares [Fermilab; Strauss, T. [thomas.strauss@lhep.unibe.ch; Szelc, A. [Yale U.; Worcester, E. [Brookhaven; Yu, F. [Fermilab

    2013-07-30

    From April to July 2013 the Snowmass Young Physicists (SYP) administered an online survey collecting the opinions and concerns of the High Energy Physics (HEP) community. The aim of this survey is to provide input into the long term planning meeting known as the Community Summer Study (CSS), or Snowmass on the Mississippi. In total, 1112 respondents took part in the survey including 74 people who had received their training within HEP and have since left for non-academic jobs. This paper presents a summary of the survey results including demographic, career outlook, planned experiments and non-academic career path information collected.

  3. A Physicist in Business: Opportunities, Pitfalls, and Lifestyle.

    Science.gov (United States)

    Woollam, John

    2007-03-01

    A traditional education in physics does not normally include business classes or dealing with opportunities to start a company, yet scientists often now start and run small companies. Physicists are mainly interested in technology. However, other factors quickly dominate chances for business success. These include finance, accounting, cash flow analysis, recruiting, interviewing, personnel issues, marketing, investments, retirement plans, patents and other not always so fun activities. Technical decisions are often strongly influenced by company finances and market-analysis. This talk discusses how to recognize opportunity, how to minimize chances for failure, and lifestyle changes one needs to be aware of before entrepreneurship involvement.

  4. Proceedings of the School for Young High Energy Physicists

    International Nuclear Information System (INIS)

    Barlow, R.J.

    1992-01-01

    The 1991 School for Young High Energy Physicists was attended by 44 first year graduate students - probably the largest number since it was started in 1972. It took place in September, at the Cosener's House, Abingdon, and was organised and funded by Rutherford Appleton Laboratory. Published here are the lectures that were given in the mornings. These were supplemented and reinforced by the work in the afternoons, which were devoted to problems and tutorials. At the end of the intensive two week course the students emerged exhausted, but with a thorough grounding in the Standard Model of Elementary Particle Physics, on which most of them are performing their experimental work. (Author)

  5. A physicists guide to The Los Alamos Primer

    International Nuclear Information System (INIS)

    Reed, B Cameron

    2016-01-01

    In April 1943, a group of scientists at the newly established Los Alamos Laboratory were given a series of lectures by Robert Serber on what was then known of the physics and engineering issues involved in developing fission bombs. Serber’s lectures were recorded in a 24 page report titled The Los Alamos Primer , which was subsequently declassified and published in book form. This paper describes the background to the Primer and analyzes the physics contained in its 22 sections. The motivation for this paper is to provide a firm foundation of the background and contents of the Primer for physicists interested in the Manhattan Project and nuclear weapons. (invited comment)

  6. Managing Inflections in Life and Career: Tale from a Physicist

    Science.gov (United States)

    Bhattacharya, Santanu

    2010-03-01

    By training, a physicist possesses one of the rarest qualities ever imparted in an educational degree program, namely, the ability to take on complex problems, divide them into ``solvable'' parts, derive solutions and put them back as insightful outputs. Dr Bhattacharya, CEO of Salorix, a research, analytics and consulting firm, explains how he has used these skills learned at the graduate school to build a career as a scientist, management consultant and entrepreneur. He will also speak about how the real-life skillsets of understanding and dealing with ``Inflections'', self discovery and introspection can be a great tool for managing one's life and career progression.

  7. Physicists set new record for network data transfer

    CERN Multimedia

    2006-01-01

    "An internatinal team of physicists, computer scientists, and network engineers led by the California Institute of Technology, CERN and the University of Michigan and partners at the University of Florida and Vanderbilt, as well as participants from Brazil (Rio de Janeiro State University, UERJ, and the State Universities of Sao Paulo, USP and UNESP) and Korea (Kyungpook National University, KISTI) joined forces to set new records for sustained data transfer between storage systems during the SuperComputing 2006 (SC06) Bandwidth Challenge (BWC)." (2 pages)

  8. Breast anatomy, physiology and pathology for the physicist

    International Nuclear Information System (INIS)

    Watson, A.B.

    1996-01-01

    Increased awareness of the importance of early breast cancer detection has spurred improvements in mammographic imaging systems and has lead to an ever-increasing role for the medical physicist. This talk will review the anatomy, physiology and pathology of the breast and discuss from a clinician's viewpoint, the proper technical and processing factors required to produce a quality mammographic study. Correct breast positioning for the MLO and CC views, adequate compression, elimination fo motion artifacts, appropriate film density and other important factors that contribute to an optimal diagnostic mammogram will also be examined. (author)

  9. Evidence for continuum absorption above the quiet sun transition region

    International Nuclear Information System (INIS)

    Schmahl, E.J.; Orrall, F.Q.

    1979-01-01

    We report new evidence for continuum absorption in the solar transition zone in EUV spectra obtained from OSO 4, OSO 6, ATM, and full Sun measurements. This absorption shortward of 912 A is manifest everywhere on the Sun's disk. It is present within network cells and boundaries of the quiet Sun, in coronal holes, in active regions, above the limb, and in solar prominences. Models of the upper chromosphere and the transition zone must be modified to include an admixture of neutral hydrogen (or possibly singly ionized helium) with the hotter plasma

  10. Study of quiet turbofan STOL aircraft for short haul transportation

    Science.gov (United States)

    Higgins, T. P.; Stout, E. G.; Sweet, H. S.

    1973-01-01

    Conceptual designs of Quiet Turbofan STOL Short-Haul Transport Aircraft for the mid-1980 time period are developed and analyzed to determine their technical, operational, and economic feasibility. A matrix of aircraft using various high-lift systems and design parameters are considered. Variations in aircraft characteristics, airport geometry and location, and operational techniques are analyzed systematically to determine their effects on the market, operating economics, and community acceptance. In these studies, the total systems approach is considered to be critically important in analyzing the potential of STOL aircraft to reduce noise pollution and alleviate the increasing air corridor and airport congestion.

  11. Physicists polish one model while looking to the next

    International Nuclear Information System (INIS)

    Hellemans, A.

    1995-01-01

    High-energy physicists' current explanation for the behavior of subatomic particles and forces, known as the Standard Model, is doing just fine. That was the take-home message for the 800 delegates who gathered here from 27 July to 2 August for the international Europhysics Conference on High-Energy Physics. open-quotes Mainly this was a conference of consolidation, steady progress, many very beautiful and detailed results,close quotes Christopher Llewellyn Smith, director general of CERN, the European particle physics laboratory, told Science. But while a multitude of presentations described ever more accurate tests and confirmations of the model, physicists also discussed hints that a whole new range of phenomena beyond the Standard Model is lurking just above the energies of current accelerators-and within range of the next generation of experiments. Other topics covered in this meeting report include the practical side of detecting and recording events in future particle accelerators and some new information on the elusive neutrino

  12. High energy physicists and graduate students: 1981 census

    International Nuclear Information System (INIS)

    1982-02-01

    This listing of physicists and students associated with the US high energy physics program has been compiled in the Division of High Energy Physics of the Office of Energy Research of the US Department of Energy. This listing has been obtained by asking the research groups, laboratories, and other agencies involved to update previous information. This volume is in two parts. The first part is an alphabetical listing and includes only the name, rank, and institution of high energy physicists and graduate students. The second part of the volume is arranged by institution. Within each institution, the faculty (or permanent staff) and the graduate students are presented in separate alphabetical lists. For each person the entry indicates their birthdate, the year and institution of their highest degree, their rank and institutional affiliation with starting dates, up to three items selected from a list of research specialties, and their sources of federal support. For the graduate students, there is also indicated an estimated date for their degree. Where appropriate, a person is listed at more than one institution. Except as noted in the headings, the information is intended to indicate the situation as of January 1, 1981

  13. High energy physicists and graduate students. 1978 census

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-11-01

    This listing of physicists and students associated with the U.S. high-energy physics program was obtained by asking the research groups, laboratories, and other agencies involved to update previous information. The first part of this volume is an alphabetical listing and includes only the name, rank, and institution of high-energy physicists and graduate students. The second part of the volume is arranged by institution. Within each institution, the faculty (or permanent staff) and the graduate students are presented in separate alphabetical lists. For each person the entry indicates the year and institution of highest degree, rank and institutional affiliation with starting dates, up to three items selected from a list of research specialties, and sources of federal support. For the graduate students, there is also indicated an estimated date for their degree. Where appropriate, a person is listed at more than one institution. Except as noted in the headings, the information is intended to indicate the situation as of January 1, 1978. (RWR)

  14. High energy physicists and graduate students. 1978 census

    International Nuclear Information System (INIS)

    1978-11-01

    This listing of physicists and students associated with the U.S. high-energy physics program was obtained by asking the research groups, laboratories, and other agencies involved to update previous information. The first part of this volume is an alphabetical listing and includes only the name, rank, and institution of high-energy physicists and graduate students. The second part of the volume is arranged by institution. Within each institution, the faculty (or permanent staff) and the graduate students are presented in separate alphabetical lists. For each person the entry indicates birthdate, the year and institution of highest degree, rank and institutional affiliation with starting dates, up to three items selected from a list of research specialties, and sources of federal support. For the graduate students, there is also indicated an estimated date for their degree. Where appropriate, a person is listed at more than one institution. Except as noted in the headings, the information is intended to indicate the situation as of January 1, 1978

  15. A Physicist's Journey In The Nuclear Power World

    Science.gov (United States)

    Starr, Chauncey

    2000-03-01

    As a participant in the development of civilian nuclear power plants for the past half century, the author presents some of his insights to its history that may be of interest to today's applied physicists. Nuclear power development has involved a mixture of creative vision, science, engineering, and unusual technical, economic, and social obstacles. Nuclear power programs were initiated during the euphoric era of public support for new science immediately following World War II -- a support that lasted almost two decades. Subsequently, nuclear power has had to face a complex mix of public concerns and criticism. The author's involvment in some of these circumstances will be anecdotally described. Although the physics of fission and its byproducts remains at the heart of all nuclear reactor designs, its embodiment in practical energy sources has been shaped by the limitations of engineering primarily and economics secondarily. Very influential has been the continuing interplay with the military's weapons and propulsion programs, and the government's political policies. In this respect, nuclear power's history provides a learning experience that may be applicable to some of the large scale demonstration projects that physicists pursue today.

  16. The Battle for Heavy Water Three physicists' heroic exploits

    CERN Multimedia

    2002-01-01

    Up until the end of the 1970s you could still catch a glimpse of his massive silhouette in the corridors of CERN. Lew Kowarksi, one of the pioneers of the Laboratory, was not only a great physicist; he was also a genuine hero of World War II. In 1940, along with Frédéric Joliot and Hans von Halban, Lew Kowarski managed to get the entire world supply of heavy water away to safety from the Nazis after a fantastic escape from occupied France. At the end of the war, the three physicists played themselves in a film about their adventures entitled 'la Bataille de l'eau lourde'. This film, which has been loaned to us by the French National Film Library, will be shown at CERN for the first time next Thursday. At the beginning of the war, heavy water (D20, two atoms of deuterium and one oxygen atom) was of strategic importance. In 1939 Frédéric Joliot, aided by Hans von Halban and Lew Kowarski, demonstrated the nuclear chain reaction and the moderator role that heavy water plays in it. A few weeks before the inv...

  17. Got Skills? On-the-Job Activities of Physicists

    Science.gov (United States)

    Ivie, Rachel

    2011-03-01

    It goes almost without saying that physics doctorates do a lot more than just physics research or teaching at their jobs. But what exactly do they do? First, I will share basic data showing where physics doctorates are employed. Then I will present data from two of AIP's surveys about the employment of physicists. The first set of data comes from our survey of physics PhDs one year after doctorate. We will consider how often physics doctorates do a variety of activities on the job, including management, technical writing, teamwork, design and development, programming, and advanced mathematics. The second set of data comes from AIP's new survey of PhDs in physics 10 to 13 years after graduation. Data for many of the same activities will be shown for physics doctorates who have been in the workplace about a decade. Depending on the type of job, most industrially employed physics doctorates do some type of physics at work, but they are also very likely to report managing projects, writing for technical audiences, working on a team, and collaborating with non-physicists, among many other activities. This examination of the types of activities physics doctorates perform in the workplace will provide insight on the non-scientific training that would benefit graduate students the most.

  18. You Don't Look Like a Physicist

    Science.gov (United States)

    Santos, Antonio Carlos Fontes

    2017-12-01

    "You don't look like a physicist!" "Sorry, this bus only goes to the university, Sir." "Where are you going, sir?" "So, you are a university professor? But a substitute one, aren't you?" "OK, you're a professor, but do you do research?" As a person of color teaching physics in Brazil, those are some comments that I usually hear. They are consequences of stereotypes, prejudices, and discrimination, which are related but different ideas. Stereotypes indicate expectations and beliefs about an individual or a group, prejudice denotes feelings, and discrimination expresses behaviors. People are likely to be astonished whenever a Black person says that he or she is a physicist. This paper aims to raise awareness of the underrepresentation of Black physics professors and researchers in Brazil and how the lack of quality high school physics education impacts Black and poor students in Brazil. Finally, some considerations on how physics education can assist minority students in overcoming social barriers that contribute to their underrepresentation are presented.

  19. Nuclear forces the making of the physicist Hans Bethe

    CERN Document Server

    Schweber, Silvan S

    2012-01-01

    On the fiftieth anniversary of Hiroshima, Nobel-winning physicist Hans Bethe called on his fellow scientists to stop working on weapons of mass destruction. What drove Bethe, the head of Theoretical Physics at Los Alamos during the Manhattan Project, to renounce the weaponry he had once worked so tirelessly to create? That is one of the questions answered by "Nuclear Forces", a riveting biography of Bethe's early life and development as both a scientist and a man of principle. As Silvan Schweber follows Bethe from his childhood in Germany, to laboratories in Italy and England, and on to Cornell University, he shows how these differing environments were reflected in the kind of physics Bethe produced. Many of the young quantum physicists in the 1930s, including Bethe, had Jewish roots, and Schweber considers how Liberal Judaism in Germany helps explain their remarkable contributions. A portrait emerges of a man whose strategy for staying on top of a deeply hierarchical field was to tackle only those problems h...

  20. Chromospheric Heating due to Cancellation of Quiet Sun Internetwork Fields

    Science.gov (United States)

    Gošić, M.; de la Cruz Rodríguez, J.; De Pontieu, B.; Bellot Rubio, L. R.; Carlsson, M.; Esteban Pozuelo, S.; Ortiz, A.; Polito, V.

    2018-04-01

    The heating of the solar chromosphere remains one of the most important questions in solar physics. Our current understanding is that small-scale internetwork (IN) magnetic fields play an important role as a heating agent. Indeed, cancellations of IN magnetic elements in the photosphere can produce transient brightenings in the chromosphere and transition region. These bright structures might be the signature of energy release and plasma heating, probably driven by the magnetic reconnection of IN field lines. Although single events are not expected to release large amounts of energy, their global contribution to the chromosphere may be significant due to their ubiquitous presence in quiet Sun regions. In this paper, we study cancellations of IN elements and analyze their impact on the energetics and dynamics of the quiet Sun atmosphere. We use high-resolution, multiwavelength, coordinated observations obtained with the Interface Region Imaging Spectrograph and the Swedish 1 m Solar Telescope (SST) to identify cancellations of IN magnetic flux patches and follow their evolution. We find that, on average, these events live for ∼3 minutes in the photosphere and ∼12 minutes in the chromosphere and/or transition region. Employing multi-line inversions of the Mg II h and k lines, we show that cancellations produce clear signatures of heating in the upper atmospheric layers. However, at the resolution and sensitivity accessible to the SST, their number density still seems to be one order of magnitude too low to explain the global chromospheric heating.

  1. Energy distribution of nanoflares in the quiet solar corona

    Science.gov (United States)

    Ulyanov, Artyom

    2012-07-01

    We present a detailed statistical analysis of flare-like events in low layer of solar corona detected with TESIS instrument onboard CORONAS-PHOTON satellite in 171 {Å} during high-cadence (5 sec) time-series. The estimated thermal energies of these small events amount to 10^{23} - 10^{26} erg. According to modern classification flare-like events with such energies are usually referred to as nanoflares. The big number of registered events (above 2000) allowed us to obtain precise distributions of geometric and physical parameters of nanoflares, the most intriguing being energy distribution. Following Aschwanden et al. (2000) and other authors we approximated the calculated energy distribution with a single power law slope: N(E)dE ˜ N^{-α}dE. The power law index was derived to be α = 2.4 ± 0.2, which is very close to the value reported by Krucker & Benz (1998): α ≈ 2.3 - 2.4. The total energy input from registered events constitute about 10^4 erg \\cdot cm^{-2} \\cdot s^{-1}, which is well beyond net losses in quiet corona (3 \\cdot 10^5 erg \\cdot cm^{-2} \\cdot s^{-1}). However, the value of α > 2 indicates that nanoflares with lower energies dominate over nanoflares with bigger energies and could contribute considerably to quiet corona heating.

  2. Small-scale Magnetic Flux Emergence in the Quiet Sun

    Science.gov (United States)

    Moreno-Insertis, F.; Martinez-Sykora, J.; Hansteen, V. H.; Muñoz, D.

    2018-06-01

    Small bipolar magnetic features are observed to appear in the interior of individual granules in the quiet Sun, signaling the emergence of tiny magnetic loops from the solar interior. We study the origin of those features as part of the magnetoconvection process in the top layers of the convection zone. Two quiet-Sun magnetoconvection models, calculated with the radiation-magnetohydrodynamic (MHD) Bifrost code and with domain stretching from the top layers of the convection zone to the corona, are analyzed. Using 3D visualization as well as a posteriori spectral synthesis of Stokes parameters, we detect the repeated emergence of small magnetic elements in the interior of granules, as in the observations. Additionally, we identify the formation of organized horizontal magnetic sheets covering whole granules. Our approach is twofold, calculating statistical properties of the system, like joint probability density functions (JPDFs), and pursuing individual events via visualization tools. We conclude that the small magnetic loops surfacing within individual granules in the observations may originate from sites at or near the downflows in the granular and mesogranular levels, probably in the first 1 or 1.5 Mm below the surface. We also document the creation of granule-covering magnetic sheet-like structures through the sideways expansion of a small subphotospheric magnetic concentration picked up and pulled out of the interior by a nascent granule. The sheet-like structures that we found in the models may match the recent observations of Centeno et al.

  3. Companions of low-redshift radio-quiet quasars

    International Nuclear Information System (INIS)

    Yee, H.K.C.

    1987-01-01

    Using imaging data from a relatively complete subset of low-redshift radio-quiet quasars, the frequency of finding associated companion galaxies of the quasars is determined statistically. With an average completeness limit of M/sub r/ of about -19, it is found that about 40 percent of the quasars have at least one close physical companion within a projected distance of 100 kpc. The percentage of quasars with detected companions is consistent with all quasars in the sample having a companion of luminosity brighter than about -16.5 mag. It is estimated that the frequency of finding close companions to quasars is about six times higher than that expected for field galaxies. This frequency is similar to that found for lower-luminosity Seyfert galaxies. The properties of the companions appear to be uncorrelated with the level of activity in the quasars. This suggests that, for radio-quiet quasars, the companions act mainly as triggers of the activity and are probably not a strong determining factor of the detailed properties of the quasars. 28 references

  4. Thirty year celebration of the contribution of nuclear medicine physicists in Australia

    International Nuclear Information System (INIS)

    Walker, B. M.

    2007-01-01

    Full text: The intention of this article is to describe the contributions of the many nuclear medicine physicists who in a large or small way have added to the ongoing development of nuclear medicine in Australia from the first years of the discipline in the late 1960s to the present time. Unlike our colleagues in radiation oncology physics, the nuclear medicine physicist fraternity has always been a very small group which unfortunately has not expanded greatly over the 30 years and beyond. This is emphasized in the survey by W.H.Round 1 which showed the bias towards older physicists being involved in the discipline. Because of the small numbers of nuclear medicine physicists in the public hospital system, mostly one or two per teaching hospital, most physicists are heavily involved in clinical duties to keep up the high standard of equipment and software performance required. Many nuclear medicine physicists also have the dual role of hospital radiation safety officers which is becoming more demanding as radiation legislation increases. For this reason much of the pure research has been confined to the hospitals with larger numbers of physicists. However a high proportion of nuclear medicine physicists across the country have contributed greatly to clinical research and development as part of their job. Unfortunately these cannot all be recognised in this article. Young physicists may not realise how much 'in house' research and development was carried out by physicists in the early years of nuclear medicine when equipment companies did not provide the software which is now available to purchase. Many of these innovative techniques and software, described in this article, are still in use today. Some of the 'big events' in the history of nuclear medicine in Australia in which physicists have played a leading role will also be highlighted. This will serve to emphasize how physicists have worked closely with clinicians and technologists in the ongoing development of

  5. IRAS observations of radio-quiet and radio-loud quasars

    Science.gov (United States)

    Neugebauer, G.; Soifer, B. T.; Miley, G.; Habing, H. J.; Young, E.; Low, F. J.; Beichman, C. A.; Clegg, P. E.; Harris, S.; Rowan-Robinson, M.

    1984-01-01

    Observations from 12 to 100 microns are presented of two radio-quiet and three radio-loud quasars. Over this wavelength range, all five have grossly similar continuum energy distributions. The continua of the radio-loud quasars are consistent with synchrotron radiation. There is an indication, however, of excess 100 micron emission in the two radio-quiet quasars.

  6. Guerrilla science survival strategies of a Cuban physicist

    CERN Document Server

    Altshuler, Ernesto

    2017-01-01

    Full of drama, dedication, and humor, this book narrates the author’s often frustrating experiences working as an experimental physicist in Cuba after the disintegration of the so-called socialist block. Lacking finance and infrastructure, faced with makeshift equipment, unpredictable supplies, and unreliable IT, Altshuler tells how he and his students overcame numerous challenges to make novel and interesting contributions to several fields of science. Along the way, he explains the science - from studies of ant colonies to superconductivity - either qualitatively or quantitatively, but always at a level fully understandable to an undergraduate student of natural sciences or engineering. An even wider audience, however, may skip the technical sections without missing the essence. With numerous anecdotes, photographs and the author’s own delightful cartoons, the book tells a remarkable, and often amusing story of how successful science can be performed against all odds.

  7. The role of medical physicist in radiation protection

    International Nuclear Information System (INIS)

    Nusslin, F.

    2010-01-01

    Ionizing Radiation is applied in Radiation Therapy, Nuclear medicine and Diagnostic Radiology. Radiation Protection in Medical Application of Ionizing Radiation requires specific Professional Competence in all relevant details of the radiation source instrumentation / equipment clinical dosimetry application procedures quality assurance medical risk-benefit assessment. Application in general include Justification of practices (sufficient benefit to the exposed individuals) Limitation of doses to individuals (occupational / public exposure) Optimization of Protection (magnitude and likelihood of exposures, and the number of individuals exposed will be ALARA. Competence of persons is normally assessed by the State by having a formal mechanism for registration, accreditation or certification of medical physicists in the various specialties (e.g. diagnostic radiology, radiation therapy, nuclear medicine). The patient safety in the use of medical radiation will be increased through: Consistent education and certification of medical team members, whose qualifications are recognized nationally, and who follow consensus practice guidelines that meet established national accrediting standards

  8. Review of online educational resources for medical physicists.

    Science.gov (United States)

    Prisciandaro, Joann I

    2013-11-04

    Medical physicists are often involved in the didactic training of graduate students, residents (both physics and physicians), and technologists. As part of continuing medical education, we are also involved in maintenance of certification projects to assist in the education of our peers. As such, it is imperative that we remain current concerning available educational resources. Medical physics journals offer book reviews, allowing us an opportunity to learn about newly published books in the field. A similar means of communication is not currently available for online educational resources. This information is conveyed through informal means. This review presents a summary of online resources available to the medical physics community that may be useful for educational purposes.

  9. Proceedings of the school for young high energy physicists

    International Nuclear Information System (INIS)

    Barlow, R.J.

    1993-04-01

    The 1992 School for young High Energy Physicists took place from September 6-19, at the Cosener's House, Abingdon, and was attended by virtually all United Kingdom 1st year graduate students in the field of Experimental Particle Physics. It was organised and funded by the Rutherford Appleton Laboratory, whose assistance is very gratefully acknowledged. Published here are the lectures that were given in the mornings. These were supplemented and reinforced by the work in the afternoons, which were devoted to problems and tutorials. at the end of the intensive two week course the students emerged exhausted, but with a thorough grounding in the Standard Model of Elementary Particle Physics on which most of them are performing their experimental work. (author)

  10. An introduction to tensors and group theory for physicists

    CERN Document Server

    Jeevanjee, Nadir

    2011-01-01

    An Introduction to Tensors and Group Theory for Physicists provides both an intuitive and rigorous approach to tensors and groups and their role in theoretical physics and applied mathematics. A particular aim is to demystify tensors and provide a unified framework for understanding them in the context of classical and quantum physics. Connecting the component formalism prevalent in physics calculations with the abstract but more conceptual formulation found in many mathematical texts, the work will be a welcome addition to the literature on tensors and group theory. Part I of the text begins with linear algebraic foundations, follows with the modern component-free definition of tensors, and concludes with applications to classical and quantum physics through the use of tensor products. Part II introduces abstract groups along with matrix Lie groups and Lie algebras, then intertwines this material with that of Part I by introducing representation theory. Exercises and examples are provided throughout for go...

  11. Proceedings of the School for Young High Energy Physicists

    International Nuclear Information System (INIS)

    Sedgbeer, J.; Evans, M.E.

    2003-01-01

    Forty-seven experimental particle physicists attended the 2002 Summer School, held, as usual, at The Cosener's House in Abingdon during September. The weather was glorious allowing a number of tutorials and impromptu seminars to take place in the lovely gardens. The lectures were of a high standard and were delivered and received enthusiastically, providing material for lively discussions in tutorials and elsewhere. The students each gave a ten-minute seminar and the general quality of the talks was impressive and the time keeping excellent. The activities described ranged from front-line physics analysis to preparations for the next generation of machines and detectors, and gave a clear indication of the breadth of particle physics activities in the UK

  12. High energy physicists and graduate students. 1985 Census

    International Nuclear Information System (INIS)

    1985-10-01

    An alphabetical listing is given of high energy physicists and graduate students, providing the person's name, rank, and institution. Another listing gives the faculty (or permanent staff) and graduate students for each institution, listing for each person the date of birth, year and institution of highest degree, the rank and institutional affiliation with starting dates, up to three items selected from a list of research specialties, and their sources of federal support. For the graduate students, there is also indicated an estimated date for their degree. Where appropriate, a person may be listed at more than one institution. Except as noted, the information is intended to indicate the situation as of January 1, 1985

  13. Distribution of auroral arcs during quiet geomagnetic conditions

    International Nuclear Information System (INIS)

    Lassen, K.; Danielsen, C.

    1989-01-01

    Auroral arcs observed from the Greenland all-sky camera network during quiet intervals (AE 500 eV) and a poleward, low-energy part. Previous studies have shown that the arc pattern is composed of two subpatterns, too, the polar cap are pattern and the oval arc pattern. It is demonstrated that the polar cap arc pattern is situated in the poleward, low-energy part of the precipitation belt, connected to the low-latitude boundary layer, whereas the oval arc pattern is in the equatorial higher energy belt, connected to the plasma sheet. The dividing line between the two arc patterns is associated with the boundary of trapped ≥ 40-keV electrons. The designation polar cap arc pattern is shown to be ambiguous, wherefore it is proposed to replace it by the term high-latitude arc pattern

  14. On the magnetic effect of the quiet ring current

    International Nuclear Information System (INIS)

    Feldstein, Ya.I.; Porchkhidze, Ts.D.

    1983-01-01

    Magnetic effects of the quiet ring current DRsu (q) along the geomagnetic equator near a minimUm of solar activity are considered. The division of Dsub(st)-variation of the geomagnetic field observed on the Earth's surface into DCF and DR components for January 23-24, 1974 has been carried out. DRsup(q) being 16.7 nT. A comparison with the magnetic field of the ring current and the energy particles moving round the Earth in the radiation zone shows a good agreement in the intensities obtained by two methods. This means that in calculating the Dsub(st)-index the values of the H-component of the field are taken as a bench mark during such time intervals when the DRsup(q) field is approximately compensated by the fields of currents on the magnetopause DCFsup(q). The estimates giVe RCsup(q) approximately - 12 nT

  15. Quiet High Speed Fan II (QHSF II): Final Report

    Science.gov (United States)

    Kontos, Karen; Weir, Don; Ross, Dave

    2012-01-01

    This report details the aerodynamic, mechanical, structural design and fabrication of a Honey Engines Quiet High Speed Fan II (lower hub/tip ratio and higher specific flow than the Baseline I fan). This fan/nacelle system incorporates features such as advanced forward sweep and an advanced integrated fan/fan exit guide vane design that provides for the following characteristics: (1) Reduced noise at supersonic tip speeds, in comparison to current state-of-the-art fan technology; (2) Improved aeroelastic stability within the anticipated operating envelope; and (3) Aerodynamic performance consistent with current state-of-the-art fan technology. This fan was fabricated by Honeywell and tested in the NASA Glenn 9- by 15-Ft Low Speed Wind Tunnel for aerodynamic, aeromechanical, and acoustic performance.

  16. Quiet living. Challenges of citizen participation in digitized society

    DEFF Research Database (Denmark)

    Stald, Gitte Bang

    Quiet living. Challenges of citizen participation in digitized society The aim of this paper is to present and address challenges that citizens may encounter in the intersecting questions of democracy, digitization, and participation. Empirically, the paper draws on findings from an extensive study......, and perceptions of citizenship. From 2011 and forwards a new digitization strategy for public systems has been implemented in Denmark. According to the strategy, all interactions between the system and the citizen in its multiple contexts are now by default digital and online. The logic is that Denmark is among...... media and media content from their private sphere as well as from their work or education. Denmark can therefore be characterized as a digital society. The following quotes from the media literacy study illustrate two different situations and experiences with digitization of citizen life: “Before .. You...

  17. MO-E-213-01: Increasing Role of Medical Physicist in Radiation Protection

    International Nuclear Information System (INIS)

    Rehani, M.

    2015-01-01

    The focus of work of medical physicists in 1980’s was on quality control and quality assurance. Radiation safety was important but was dominated by occupational radiation protection. A series of over exposures of patients in radiotherapy, nuclear medicine and observation of skin injuries among patients undergoing interventional procedures in 1990’s started creating the need for focus on patient protection. It gave medical physicists new directions to develop expertise in patient dosimetry and dose management. Publications creating awareness on cancer risks from CT in early part of the current century and over exposures in CT in 2008 brought radiation risks in public domain and created challenging situations for medical physicists. Increasing multiple exposures of individual patient and patient doses of few tens of mSv or exceeding 100 mSv are increasing the role of medical physicists. Expansion of usage of fluoroscopy in the hands of clinical professionals with hardly any training in radiation protection shall require further role for medical physicists. The increasing publications in journals, recent changes in Safety Standards, California law, all increase responsibilities of medical physicists in patient protection. Newer technological developments in dose efficiency and protective devices increase percentage of time devoted by medical physicists on radiation protection activities. Without radiation protection, the roles, responsibilities and day-to-day involvement of medical physicists in diagnostic radiology becomes questionable. In coming years either medical radiation protection may emerge as a specialty or medical physicists will have to keep major part of day-to-day work on radiation protection. Learning Objectives: To understand how radiation protection has been increasing its role in day-to-day activities of medical physicist To be aware about international safety Standards, national and State regulations that require higher attention to radiation

  18. MO-E-213-02: Medical Physicist Involvement in Implementing Patient Protection Standards

    International Nuclear Information System (INIS)

    Seibert, J.

    2015-01-01

    The focus of work of medical physicists in 1980’s was on quality control and quality assurance. Radiation safety was important but was dominated by occupational radiation protection. A series of over exposures of patients in radiotherapy, nuclear medicine and observation of skin injuries among patients undergoing interventional procedures in 1990’s started creating the need for focus on patient protection. It gave medical physicists new directions to develop expertise in patient dosimetry and dose management. Publications creating awareness on cancer risks from CT in early part of the current century and over exposures in CT in 2008 brought radiation risks in public domain and created challenging situations for medical physicists. Increasing multiple exposures of individual patient and patient doses of few tens of mSv or exceeding 100 mSv are increasing the role of medical physicists. Expansion of usage of fluoroscopy in the hands of clinical professionals with hardly any training in radiation protection shall require further role for medical physicists. The increasing publications in journals, recent changes in Safety Standards, California law, all increase responsibilities of medical physicists in patient protection. Newer technological developments in dose efficiency and protective devices increase percentage of time devoted by medical physicists on radiation protection activities. Without radiation protection, the roles, responsibilities and day-to-day involvement of medical physicists in diagnostic radiology becomes questionable. In coming years either medical radiation protection may emerge as a specialty or medical physicists will have to keep major part of day-to-day work on radiation protection. Learning Objectives: To understand how radiation protection has been increasing its role in day-to-day activities of medical physicist To be aware about international safety Standards, national and State regulations that require higher attention to radiation

  19. MO-E-213-02: Medical Physicist Involvement in Implementing Patient Protection Standards

    Energy Technology Data Exchange (ETDEWEB)

    Seibert, J. [UC Davis Medical Center (United States)

    2015-06-15

    The focus of work of medical physicists in 1980’s was on quality control and quality assurance. Radiation safety was important but was dominated by occupational radiation protection. A series of over exposures of patients in radiotherapy, nuclear medicine and observation of skin injuries among patients undergoing interventional procedures in 1990’s started creating the need for focus on patient protection. It gave medical physicists new directions to develop expertise in patient dosimetry and dose management. Publications creating awareness on cancer risks from CT in early part of the current century and over exposures in CT in 2008 brought radiation risks in public domain and created challenging situations for medical physicists. Increasing multiple exposures of individual patient and patient doses of few tens of mSv or exceeding 100 mSv are increasing the role of medical physicists. Expansion of usage of fluoroscopy in the hands of clinical professionals with hardly any training in radiation protection shall require further role for medical physicists. The increasing publications in journals, recent changes in Safety Standards, California law, all increase responsibilities of medical physicists in patient protection. Newer technological developments in dose efficiency and protective devices increase percentage of time devoted by medical physicists on radiation protection activities. Without radiation protection, the roles, responsibilities and day-to-day involvement of medical physicists in diagnostic radiology becomes questionable. In coming years either medical radiation protection may emerge as a specialty or medical physicists will have to keep major part of day-to-day work on radiation protection. Learning Objectives: To understand how radiation protection has been increasing its role in day-to-day activities of medical physicist To be aware about international safety Standards, national and State regulations that require higher attention to radiation

  20. MO-E-213-01: Increasing Role of Medical Physicist in Radiation Protection

    Energy Technology Data Exchange (ETDEWEB)

    Rehani, M. [Massachusetts General Hospital (United States)

    2015-06-15

    The focus of work of medical physicists in 1980’s was on quality control and quality assurance. Radiation safety was important but was dominated by occupational radiation protection. A series of over exposures of patients in radiotherapy, nuclear medicine and observation of skin injuries among patients undergoing interventional procedures in 1990’s started creating the need for focus on patient protection. It gave medical physicists new directions to develop expertise in patient dosimetry and dose management. Publications creating awareness on cancer risks from CT in early part of the current century and over exposures in CT in 2008 brought radiation risks in public domain and created challenging situations for medical physicists. Increasing multiple exposures of individual patient and patient doses of few tens of mSv or exceeding 100 mSv are increasing the role of medical physicists. Expansion of usage of fluoroscopy in the hands of clinical professionals with hardly any training in radiation protection shall require further role for medical physicists. The increasing publications in journals, recent changes in Safety Standards, California law, all increase responsibilities of medical physicists in patient protection. Newer technological developments in dose efficiency and protective devices increase percentage of time devoted by medical physicists on radiation protection activities. Without radiation protection, the roles, responsibilities and day-to-day involvement of medical physicists in diagnostic radiology becomes questionable. In coming years either medical radiation protection may emerge as a specialty or medical physicists will have to keep major part of day-to-day work on radiation protection. Learning Objectives: To understand how radiation protection has been increasing its role in day-to-day activities of medical physicist To be aware about international safety Standards, national and State regulations that require higher attention to radiation

  1. Using an adaptive fuzzy-logic system to optimize the performances and the reduction of chattering phenomenon in the control of induction motor

    Directory of Open Access Journals (Sweden)

    Barazane Linda

    2009-01-01

    Full Text Available Neural networks and fuzzy inference systems are becoming well recognized tools of designing an identifier/controller capable of perceiving the operating environment and imitating a human operator with high performance. Also, by combining these two features, more versatile and robust models, called 'neuro-fuzzy' architectures have been developed. The motivation behind the use of neuro-fuzzy approaches is based on the complexity of real life systems, ambiguities on sensory information or time-varying nature of the system under investigation. In this way, the present contribution concerns the application of neuro-fuzzy approach in order to perform the responses of the speed regulation and to reduce the chattering phenomenon introduced by sliding mode control, which is very harmful to the actuators in our case and may excite the unmodeled dynamics of the system. The type of the neuro-fuzzy system used here is called:' adaptive neuro fuzzy inference controller (ANFIS'. This neuro-fuzzy is destined to replace the speed fuzzy sliding mode controller after its training process. Simulation results reveal some very interesting features. .

  2. Life as an Ex-Physicist on Wall Street

    Science.gov (United States)

    Derman, Emanuel

    2001-06-01

    Financial theory looks deceptively like physics because of the techniques it uses. But physics models deal with the relatively unchanging parameters of the external world; in contrast, the parameters of financial theory are people's current estimates of, and sentiments about, future behavior. Life as a Ph.D. on Wall St is therefore very different from the way most people in academic life imagine it to be. For most of us, most of the time, it involves neither finding miraculous and previously undiscovered arbitrages, nor doing boring mindless programming. Instead, it demands an interdisciplinary mix of inventive computation, applied mathematics, financial understanding, self-education and educating others, applied in a hectic environment, to help build and maintain a business. Financial modeling as a practitioner means suffering many interruptions when you want to think quietly, and making many pragmatic compromises dictated by constraints on time and resources. It also means a stimulating and lively environment, using your imagination, avoiding complexity, and always trying to bridge the gap between analysis and intuition (yours and others).

  3. Is the "glass ceiling" a real problem for women physicists in Argentina?

    Science.gov (United States)

    Frechero, Marisa A.; Amador, Ana; Pastor, Antonio J. Ramirez; Tamarit, Francisco

    2015-12-01

    We evaluate the distribution of female physicists in the Argentinean workforce, analyzing the distribution of women at different levels of education and research using several indicators. Although important imbalances still occur, our findings are encouraging and the distribution of female physicists seems to be changing for the better.

  4. Particle accelerators installed in hospitals: the need for a program of training for medical physicists

    International Nuclear Information System (INIS)

    Brandan, M.E.

    1989-01-01

    This paper was presented at the session which closed the round table. The need for setting up a program of professional training directed by hospital physicists who have functioned for some time as medical physicists in the health centers of the country was proposed. (Author)

  5. The role of the biomedical physicist in the education of the healthcare professions: An EFOMP project

    NARCIS (Netherlands)

    Caruana, C.J.; Wasilewska-Radwanska, M.; Aurengo, A.; Dendy, P.P.; Karenauskaite, V.; Malisan, M.R.; Meijer, J.H.; Mornstein, V.; Rokita, E.; Vano, E.; Wucherer, M.

    2009-01-01

    The role of the biomedical physicist in the education of the healthcare professions has not yet been studied in a systematic manner. This article presents the first results of an EFOMP project aimed at researching and developing this important component of the role of the biomedical physicist. A

  6. Long the fixation of physicists worldwide, a tiny particle is found

    CERN Multimedia

    2006-01-01

    "After decades of intensive effort by both experimental and theoretical physicists worldwide, a tiny particle with no charge, a very low mass and a lifetime much shorter than a nanosecond, dubbed the "axion", has now been detected by the University at Buffalo physicist who first suggested its existence in a little-read paper as early as 194." (2 pages)

  7. Do Quiet Areas Afford Greater Health-Related Quality of Life than Noisy Areas?

    Directory of Open Access Journals (Sweden)

    Kim N. Dirks

    2013-03-01

    Full Text Available People typically choose to live in quiet areas in order to safeguard their health and wellbeing. However, the benefits of living in quiet areas are relatively understudied compared to the burdens associated with living in noisy areas. Additionally, research is increasingly focusing on the relationship between the human response to noise and measures of health and wellbeing, complementing traditional dose-response approaches, and further elucidating the impact of noise and health by incorporating human factors as mediators and moderators. To further explore the benefits of living in quiet areas, we compared the results of health-related quality of life (HRQOL questionnaire datasets collected from households in localities differentiated by their soundscapes and population density: noisy city, quiet city, quiet rural, and noisy rural. The dose-response relationships between noise annoyance and HRQOL measures indicated an inverse relationship between the two. Additionally, quiet areas were found to have higher mean HRQOL domain scores than noisy areas. This research further supports the protection of quiet locales and ongoing noise abatement in noisy areas.

  8. IS THE POLAR REGION DIFFERENT FROM THE QUIET REGION OF THE SUN?

    International Nuclear Information System (INIS)

    Ito, Hiroaki; Shiota, Daikou; Tokumaru, Munetoshi; Fujiki, Ken'ichi; Tsuneta, Saku

    2010-01-01

    Observations of the polar region of the Sun are critically important for understanding the solar dynamo and the acceleration of solar wind. We carried out precise magnetic observations on both the north polar region and the quiet Sun at the east limb with the spectropolarimeter of the Solar Optical Telescope aboard Hinode to characterize the polar region with respect to the quiet Sun. The average area and the total magnetic flux of the kilo-Gauss magnetic concentrations in the polar region appear to be larger than those of the quiet Sun. The magnetic field vectors classified as vertical in the quiet Sun have symmetric histograms around zero in the strengths, showing balanced positive and negative fluxes, while the histogram in the north polar region is clearly asymmetric, showing a predominance of the negative polarity. The total magnetic flux of the polar region is larger than that of the quiet Sun. In contrast, the histogram of the horizontal magnetic fields is exactly the same for both the polar region and the quiet Sun. This is consistent with the idea that a local dynamo process is responsible for the horizontal magnetic fields. A high-resolution potential field extrapolation shows that the majority of magnetic field lines from the kG-patches in the polar region are open with a fanning-out structure very low in the atmosphere, while in the quiet Sun, almost all the field lines are closed.

  9. MO-A-218-01: CT Protocol Review - Practical Tips for Imaging Physicists.

    Science.gov (United States)

    Pizzutiello, R

    2012-06-01

    In the 1980's and 90's, when every mammography department had a wet film processor and a sundial to keep the schedule, medical physicists performing mammography surveys were primarily focused on measuring machine performance and image quality. As our professional experience matured, medical physicists began to learn that they were uniquely qualified to help to recommend technique factors that would balance dose and image quality. Technique charts using different kVp, target-filter combinations and AEC modes gradually became common and patients benefitted from our input. With the revolutionary change in CT Scanner technology and utilization, medical physicists have begun to contribute their expertise to developing and improving CT protocols. This presentation will present practical challenges and offer some directions for the practicing medical physicist who desires to participate in this critical and emerging aspect of imaging physics practice: CT Protocol Review. © 2012 American Association of Physicists in Medicine.

  10. Physicists develop more powerful tools to combat cancer

    CERN Multimedia

    Antonella Del Rosso and Fabio Capello

    2012-01-01

    The tools physicists are currently sharing with doctors to defeat cancer are high-tech sensors for early detection and particles for use as sharp projectiles. The latest advances in medical physics and some of the most sophisticated devices for imaging, monitoring and treatment were presented at the ICTR-PHE 2012 conference. They will shape the future of advanced healthcare.   @font-face { font-family: "Cambria Math"; }@font-face { font-family: "Cambria"; }p.MsoNormal, li.MsoNormal, div.MsoNormal { margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: Cambria; }p.MsoCommentText, li.MsoCommentText, div.MsoCommentText { margin: 0cm 0cm 0.0001pt; font-size: 10pt; font-family: Cambria; }span.MsoCommentReference { }a:link, span.MsoHyperlink { color: blue; text-decoration: underline; }a:visited, span.MsoHyperlinkFollowed { color: purple; text-decoration: underline; }span.CommentTextChar { }.MsoChpDefault { font-size: 10pt; font-family: Cambria; }div.WordSection1 { page: WordSection1; } So...

  11. Dark matter CMB constraints and likelihoods for poor particle physicists

    Energy Technology Data Exchange (ETDEWEB)

    Cline, James M.; Scott, Pat, E-mail: jcline@physics.mcgill.ca, E-mail: patscott@physics.mcgill.ca [Department of Physics, McGill University, 3600 rue University, Montréal, QC, H3A 2T8 (Canada)

    2013-03-01

    The cosmic microwave background provides constraints on the annihilation and decay of light dark matter at redshifts between 100 and 1000, the strength of which depends upon the fraction of energy ending up in the form of electrons and photons. The resulting constraints are usually presented for a limited selection of annihilation and decay channels. Here we provide constraints on the annihilation cross section and decay rate, at discrete values of the dark matter mass m{sub χ}, for all the annihilation and decay channels whose secondary spectra have been computed using PYTHIA in arXiv:1012.4515 (''PPPC 4 DM ID: a poor particle physicist cookbook for dark matter indirect detection''), namely e, μ, τ, V → e, V → μ, V → τ, u, d s, c, b, t, γ, g, W, Z and h. By interpolating in mass, these can be used to find the CMB constraints and likelihood functions from WMAP7 and Planck for a wide range of dark matter models, including those with annihilation or decay into a linear combination of different channels.

  12. Dark matter CMB constraints and likelihoods for poor particle physicists

    International Nuclear Information System (INIS)

    Cline, James M.; Scott, Pat

    2013-01-01

    The cosmic microwave background provides constraints on the annihilation and decay of light dark matter at redshifts between 100 and 1000, the strength of which depends upon the fraction of energy ending up in the form of electrons and photons. The resulting constraints are usually presented for a limited selection of annihilation and decay channels. Here we provide constraints on the annihilation cross section and decay rate, at discrete values of the dark matter mass m χ , for all the annihilation and decay channels whose secondary spectra have been computed using PYTHIA in arXiv:1012.4515 (''PPPC 4 DM ID: a poor particle physicist cookbook for dark matter indirect detection''), namely e, μ, τ, V → e, V → μ, V → τ, u, d s, c, b, t, γ, g, W, Z and h. By interpolating in mass, these can be used to find the CMB constraints and likelihood functions from WMAP7 and Planck for a wide range of dark matter models, including those with annihilation or decay into a linear combination of different channels

  13. The medical physicist in a nuclear medicine department

    International Nuclear Information System (INIS)

    Trujillo Z, F.E.; Gomez A, E.

    2007-01-01

    The diagnostic studies and therapeutic treatments carried out in a Nuclear Medicine department make use of radioactive material. For such a reason it becomes necessary to take a strict control in the reception, use and waste that are generated of the typical works inside the department. Also, work related with the quality control of the equipment dedicated to produce images and of those not image formers, need to carry out to guarantee its maximum performance; as well as quality of the diagnostic and of the therapy imparted in patients. Additionally its are needed to make originated works of the individual procedures to patient and of the acquisition of radioactive materials and removal of the waste or radioactive contaminations. Presently work the recommendations of the American College of Radiology (ACR), the European Federation of Organizations for Medical Physics (EFOMP) and of the Mexican Official Standards relating to the functions that should be observed in a Nuclear Medicine Department are exposed. The ACR and the EFOMP, conclude in their recommendations that the medical physicist fulfills with the suitable profile and likewise they describe in detail the actions and functions that he should supervise, to carry out, to document and to inform. (Author)

  14. A Physicist Role in Innovation within IBM Research

    Science.gov (United States)

    Gallagher, William

    2014-03-01

    The broad and deep insight a physicist brings to the goings on in a large technology company lead to many varied and exciting opportunities. Examples in my own career include contributions to important understanding of new breakthroughs (understanding the basic anisotropy of high temperature superconductivity), bringing vital physics understanding to ambitious engineering projects (basic switching and noise margins in digital Josephson junction technology), and initiating and growing large applied projects based on fundamental physics breakthroughs (magnetoresistive random access memory - MRAM). Success at such undertakings within a large enterprise involves a number of factors. Always seeking out the best expert advice and the best collaborators in unfamiliar technical areas as new ideas develop is enormously helpful and not at all difficult within a large innovative organization. While being imaginative and optimistic, one must also remain brutally honest about the potential value of new endeavors, the hurdles ahead, and the likelihood of success. Always, however, there is no substitute hard work. I can attest that the results of efforts along these directions within a technology company can be very exciting and satisfying, and the process along the way a whole lot of fun.

  15. Discovery Mondays - The particle physicist's best friend: electricity

    CERN Document Server

    2005-01-01

    One of CERN's electrical substations, at Prévessin. Electricity is one of CERN's closest allies. Without it, none of the physicists' extraordinary instruments would work. It is electricity that will guide and accelerate particles around the 27-km ring of the world's most powerful accelerator, the LHC. In the giant magnets inside the experiments electricity is also used to produce a magnetic field 200,000 times greater than the Earth's own magnetic field. Inside the detectors, the resulting magnetic force is used to bend the trajectories of the particles, allowing them to be identified and helping us gain a better understanding of what has happened at the heart of the collisions. Understanding how magnetic fields are produced inside the ATLAS experiment is one of several themes on the programme of the next Discovery Monday. And for a close-up view of operations, we'll also be taking you on a visit to the electricity substation at Meyrin. Come and meet CERN's best friend - electricity. Join us at the Micro...

  16. PET: the importance of physicists for the clinical arena

    CERN Multimedia

    2005-01-01

    David Townsend giving a seminar at CERN on 9 February. The past few years have seen significant advances in the development of instrumentation for Positron Emission Tomography (PET). The recent appearance of combined PET and Computed Tomography (CT) scanners that can simultaneously image both anatomy and function is of particular importance. This was the main subject of "Advances in PET imaging: from physics to physician", a seminar presented at CERN by David Townsend on Wednesday 9 February  and organized by the TT and PH groups. David Townsend, who started his career at CERN in the 1970s, is now Professor at the Department of Medicine, University of Tennessee Medical Center (Knoxville, TN). Recipient of the 2004 Clinical Scientist of the Year Award, he is an internationally renowned researcher and PET physicist, with over 25 years of experience in the field. His 1999 image of the year, an award from the Society of Nuclear Medicine in the US, was produced using a combined state-of-the art PET and a true d...

  17. Becoming a Physicist: How Identities and Practices Shape Physics Trajectories

    Science.gov (United States)

    Quan, Gina M.

    This dissertation studies the relationships and processes which shape students' participation within the discipline of physics. Studying this early disciplinary participation gives insight to how students are supported in or pushed out of physics, which is an important step in cultivating a diverse set of physics students. This research occurs within two learning environments that we co-developed: a physics camp for high school girls and a seminar for undergraduate physics majors to get started in physics research. Using situated learning theory, we conceptualized physics learning to be intertwined with participation in physics practices and identity development. This theoretical perspective draws our attention to relationships between students and the physics community. Specifically, we study how students come to engage in the practices of the community and who they are within the physics community. We find that students' interactions with faculty and peers impact the extent to which students engage in authentic physics practices. These interactions also impact the extent to which students develop identities as physicists. We present implications of these findings for the design of physics learning spaces. Understanding this process of how students become members of the physics community will provide valuable insights into fostering a diverse set of successful trajectories in physics.

  18. Spatiotemporal Organization of Energy Release Events in the Quiet Solar Corona

    Science.gov (United States)

    Uritsky, Vadim M.; Davila, Joseph M.

    2014-01-01

    Using data from the STEREO and SOHO spacecraft, we show that temporal organization of energy release events in the quiet solar corona is close to random, in contrast to the clustered behavior of flaring times in solar active regions. The locations of the quiet-Sun events follow the meso- and supergranulation pattern of the underling photosphere. Together with earlier reports of the scale-free event size statistics, our findings suggest that quiet solar regions responsible for bulk coronal heating operate in a driven self-organized critical state, possibly involving long-range Alfvenic interactions.

  19. Quiet Sun X-rays as Signature for New Particles

    CERN Document Server

    Zioutas, Konstantin; Di Lella, L; Hoffmann, Dieter H H; Jacoby, J; Papaevangelou, T

    2004-01-01

    We have studied published data from the Yohkoh solar X-ray mission, with the purpose of searching for signals from radiative decays of new, as yet undiscovered massive neutral particles. This search is based on the prediction that solar axions of the Kaluza-Klein type should result in the emission of X-rays from the Sun direction beyond the limb with a characteristic radial distribution. These X-rays should be observed more easily during periods of quiet Sun. An additional signature is the observed emission of hard X-rays by SMM, NEAR and RHESSI. The recent observation made by RHESSI of a continuous emission from the non-flaring Sun of X-rays in the 3 to ~15 keV range fits the generic axion scenario. This work also suggests new analyses of existing data, in order to exclude instrumental effects; it provides the rationale for targeted observations with present and upcoming (solar) X-ray telescopes, which can provide the final answer on the nature of the signals considered here. Such measurements become more pr...

  20. Local area networking in a radio quiet environment

    Science.gov (United States)

    Childers, Edwin L.; Hunt, Gareth; Brandt, Joseph J.

    2002-11-01

    The Green Bank facility of the National Radio Astronomy Observatory is spread out over 2,700 acres in the Allegheny Mountains of West Virginia. Good communication has always been needed between the radio telescopes and the control buildings. The National Radio Quiet Zone helps protect the Green Bank site from radio transmissions that interfere with the astronomical signals. Due to stringent Radio Frequency Interference (RFI) requirements, a fiber optic communication system was used for Ethernet transmissions on the site and coaxial cable within the buildings. With the need for higher speed communications, the entire network has been upgraded to use optical fiber with modern Ethernet switches. As with most modern equipment, the implementation of the control of the newly deployed Green Bank Telescope (GBT) depends heavily on TCP/IP. In order to protect the GBT from the commodity Internet, the GBT uses a non-routable network. Communication between the control building Local Area Network (LAN) and the GBT is implemented using a Virtual LAN (VLAN). This configuration will be extended to achieve isolation between trusted local user systems, the GBT, and other Internet users. Legitimate access to the site, for example by remote observers, is likely to be implemented using a virtual private network (VPN).

  1. The quiet revolution in Asia's rice value chains.

    Science.gov (United States)

    Reardon, Thomas; Chen, Kevin Z; Minten, Bart; Adriano, Lourdes; Dao, The Anh; Wang, Jianying; Gupta, Sunipa Das

    2014-12-01

    There is a rapid transformation afoot in the rice value chain in Asia. The upstream is changing quickly-farmers are undertaking capital-led intensification and participating in burgeoning markets for land rental, fertilizer and pesticides, irrigation water, and seed, and shifting from subsistence to small commercialized farms; in some areas landholdings are concentrating. Midstream, in wholesale and milling, there is a quiet revolution underway, with thousands of entrepreneurs investing in equipment, increasing scale, diversifying into higher quality, and the segments are undergoing consolidation and vertical coordination and integration. Mills, especially in China, are packaging and branding, and building agent networks in wholesale markets, and large mills are building direct relationships with supermarkets. The downstream retail segment is undergoing a "supermarket revolution," again with the lead in change in China. In most cases the government is not playing a direct role in the market, but enabling this transformation through infrastructural investment. The transformation appears to be improving food security for cities by reducing margins, offering lower consumer rice prices, and increasing quality and diversity of rice. This paper discusses findings derived from unique stacked surveys of all value chain segments in seven zones, more and less developed, around Bangladesh, China, India, and Vietnam. © 2014 New York Academy of Sciences.

  2. Determination of the decameter wavelength spectrum of the quiet sun

    International Nuclear Information System (INIS)

    Erickson, W.C.; Gergely, T.E.; Kundu, M.R.; Mahoney, M.J.

    1977-01-01

    The Teepee Tee array of the Clark Lake Radio Observatory has been used to compare the flux of the Sun with that of the sidereal sources Tau A and Vir A at several frequencies in the range 109.0-19.0 MHz. Only the two central banks of the E-W arm of the array were used as elements of a phase switched interferometer so that the Sun could be observed as a point souce and compared directly to the sidereal sources. The Sun was still partially resolved however, and appropriate corrections for this effect were made. The observations were taken at times when the Sun and either Tau A or Vir A were at the same declination. The authors have therefore been able to derive the values for the solar flux, without having to resort to a gain vs zenith distance correction. The observations, combined with those available in the literature, allow an accurate derivation of the meter and decameter wavelength spectrum of the quiet Sun. (Auth.)

  3. Driver perceptions of the safety implications of quiet electric vehicles.

    Science.gov (United States)

    Cocron, Peter; Krems, Josef F

    2013-09-01

    Previous research on the safety implications of quiet electric vehicles (EVs) has mostly focused on pedestrians' acoustic perception of EVs, and suggests that EVs are more difficult for pedestrians to hear and, therefore, compromise traffic safety. The two German field studies presented here examine the experiences of 70 drivers with low noise emissions of EVs and the drivers' long-term evaluation of the issue. Participants were surveyed via interviews and questionnaires before driving an EV for the first time, after 3 months of driving, and in the first study, again after 6 months. Based on participants' reports, a catalogue of safety-relevant incidents was composed in Study 1. The catalogue revealed that low noise-related critical incidents only rarely occur, and mostly take place in low-speed environments. The degree of hazard related to these incidents was rated as low to medium. In Study 1, driver concern for vulnerable road users as a result of low noise diminished with increasing driving experience, while perceived comfort due to this feature increased. These results were replicated in Study 2. In the second study, it was additionally examined, if drivers adjust their perceived risk of harming other road users over time. Results show that the affective assessment of risk also decreased with increased driving experience. Based on individual experience, drivers adjust their evaluation of noise-related hazards, suggesting that dangers associated with low noise emissions might be less significant than previously expected. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. MODELING THE CHROMOSPHERE OF A SUNSPOT AND THE QUIET SUN

    Energy Technology Data Exchange (ETDEWEB)

    Avrett, E.; Tian, H. [Smithsonian Astrophysical Observatory, Cambridge, MA 02138 (United States); Landi, E. [Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, Ann Arbor, MI 48109 (United States); Curdt, W. [Max Planck Institut für Sonnensystemfoschung, Goettingen (Germany); Wülser, J.-P. [Lockheed Martin Advanced Techonology Center (United States)

    2015-10-01

    Semiempirical atmospheric modeling attempts to match an observed spectrum by finding the temperature distribution and other physical parameters along the line of sight through the emitting region such that the calculated spectrum agrees with the observed one. In this paper we take the observed spectrum of a sunspot and the quiet Sun in the EUV wavelength range 668–1475 Å from the 2001 SUMER atlas of Curdt et al. to determine models of the two atmospheric regions, extending from the photosphere through the overlying chromosphere into the transition region. We solve the coupled statistical equilibrium and optically thick radiative transfer equations for a set of 32 atoms and ions. The atoms that are part of molecules are treated separately, and are excluded from the atomic abundances and atomic opacities. We compare the Mg ii k line profile observations from the Interface Region Imaging Spectrograph with the profiles calculated from the two models. The calculated profiles for the sunspot are substantially lower than the observed ones, based on the SUMER models. The only way we have found to raise the calculated Mg ii lines to agree with the observations is to introduce illumination of the sunspot from the surrounding active region.

  5. Foil Gas Bearing Supported Quiet Fan for Spacecraft Ventilation, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Developing a quiet fan for Environmental Control and Life Support systems to enhance the livable environment within the spacecraft has been a challenge. A Foil Gas...

  6. Development of an Engine Air-Brake for Quiet Drag Applications, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — A novel quiet engine air-brake is proposed in response to NASA's solicitation for concepts for active and passive control of noise sources for conventional and...

  7. Physicists band together to support a new megaproject

    International Nuclear Information System (INIS)

    Flam, F.

    1993-01-01

    As the Superconducting Super Collider (SSC) flirts with death in the congressional budget process for a second year, another mammoth science project is coming to life. Just a few days after the House voted to kill the $10 billion particle accelerator last month, it approved next year's funding for a megaproject that is a little cheaper and a lot less familiar: a $2.7 billion nuclear reactor known as the Advanced Neutron Source (ANS), to be built at Tennessee's Oak Ridge National Laboratory as a national facility for probing materials with beams of neutrons. The project's success in the House is a sign that physicists can still make a case for big science-at least when the project has a broad scientific constituency and plausible links to national competitiveness. When the facility is completed in 2002, it will be the world's most powerful neutron source, delivering 10 times the flux of neutrons produced by its nearest competitor, at the Institute Lau-Langevin in Grenoble, France. For now, designs call for a reactor about one-tenth the size of a power reactor, says project director West. Fission in the reactor core will send out a steady stream of neutrons. Slowed by heavy water to little more than walking speed, the neutrons will be carried through guides that work like fiber optic cables-by reflecting the neutrons internally, like tennis balls ricocheting down a pipe-to experiments tens or hundreds of meters away. There the neutrons will probe the atomic-scale structure of materials in a way that depends on quantum mechanical quality. Like any subatomic particles, neutrons can be thought of as waves as well as particles. When they bombard matter, their wave nature comes into play. The slow neutrons from the ANS will have a wavelength about equal to the spacing between atoms in a typical solid, making the neutrons especially sensitive to atom-by-atom architecture

  8. A health and safety primer for the practicing health physicist

    International Nuclear Information System (INIS)

    Hylko, J.M.; Bradshaw, M.C.; Ross, L.E.; Brennan, M.J.; Pomatto, C.B.; Shelly, F.C.

    1996-01-01

    Environmental restoration (ER) is the process of removing a facility from service, the demolition of structures the identification and disposal of all hazardous and radioactive wastes, the decontamination of equipment and materials, and the restoration of a site for unrestricted use. The number of ER projects encompassing hazardous, industrial, and radiological conditions is expected to increase in response to various program requirements or mission changes. As a result, the practicing health physicist (HP) may have to address unique health and safety (H and S) issues beyond those of performing routine radiological activities. These unique H and S issues could include, but are not limited to the razing of buildings, the removal of radioactive materials and hazardous chemicals, below-grade excavation, confined space entry, storing flammable or combustible liquids, monitoring exposure to hazardous substances, contacting energized systems (e.g., electricity, hydraulics), noise abatement, the nullification of manufacturer warranties, and the operation and movement of heavy equipment. The purpose of this paper is to educate the practicing HP about these issues by reviewing specific regulations governing all H and S activities, and to provide an example of a site-specific H and S primer (e.g., Health and Safety Plan [HASP]). This primer advices the practicing HP about sound H and S principles, furnishes basic strategies for performing a hazard assessment/job safety analysis (HA/JSA) that can be applied to any ER project, and describes various engineering and administrative controls to mitigate hazardous exposures to ER personnel. In addition, 26 inspection checklist topics are available from the primary author to evaluate the adequacy of the engineering and administrative controls, or to necessitate the use of personal protective equipment (PPE) thereby mitigating the corresponding hazard. (author)

  9. TU-G-213AB-01: Organization and Productivity Strategies for Practicing Medical Physicists.

    Science.gov (United States)

    Jordan, D

    2012-06-01

    Medical physicists face numerous challenges that create stress in the professional workplace. The modern work environment contains multiple communications channels, such as email, smart phones, text and instant messaging, voice mail, pagers, and more. These media make it difficult to organize incoming information, set priorities, and move important work forward in the face of rapid change and the requirement to fulfill multiple responsibilities. Medical physicists in particular are likely to feel acute stress due to off-peak work hour requirements, varied responsibilities including clinical duties, research, teaching, and regulatory matters, and the complexity of supervising other staff members. Many medical physicists also work in multiple physical locations, adding complexity to the task of organizing information and resources. Another common difficulty is that medical physicists' responsibilities typically include some duties that render them subject to frequent and urgent interruption, such as emergency response coverage for radiation safety. The real challenges in the current medical physics work environment differ from those encountered while taking courses and conducting research, as well as from earlier periods when medical physicists faced fewer varied responsibilities, slower-paced change, or both. Today's practicing physicist can benefit greatly from developing a formal framework and skill set to manage their personal workflow. This greatly increases the individual's effectiveness and reduces feelings of stress, while improving the effectiveness of teams or groups in which they participate. In this session, participants will learn about a number of techniques and strategies to manage their own personal workflow. Examples familiar to the medical physicist will be provided to illustrate methods to capture, organize, and act on important information, to delegate effectively, and to handle inevitable interruptions. 1. Describe the use of a personal workflow

  10. Future trends in the supply and demand for radiation oncology physicists.

    Science.gov (United States)

    Mills, Michael D; Thornewill, Judah; Esterhay, Robert J

    2010-04-12

    Significant controversy surrounds the 2012 / 2014 decision announced by the Trustees of the American Board of Radiology (ABR) in October of 2007. According to the ABR, only medical physicists who are graduates of a Commission on Accreditation of Medical Physics Education Programs, Inc. (CAMPEP) accredited academic or residency program will be admitted for examination in the years 2012 and 2013. Only graduates of a CAMPEP accredited residency program will be admitted for examination beginning in the year 2014. An essential question facing the radiation oncology physics community is an estimation of supply and demand for medical physicists through the year 2020. To that end, a Demand & Supply dynamic model was created using STELLA software. Inputs into the model include: a) projected new cancer incidence and prevalence 1990-2020; b) AAPM member ages and retirement projections 1990-2020; c) number of ABR physics diplomates 1990-2009; d) number of patients per Qualified Medical Physicist from Abt Reports I (1995), II (2002) and III (2008); e) non-CAMPEP physicists trained 1990-2009 and projected through 2014; f) CAMPEP physicists trained 1993-2008 and projected through 2014; and g) working Qualified Medical Physicists in radiation oncology in the United States (1990-2007). The model indicates that the number of qualified medical physicists working in radiation oncology required to meet demand in 2020 will be 150-175 per year. Because there is some elasticity in the workforce, a portion of the work effort might be assumed by practicing medical physicists. However, the minimum number of new radiation oncology physicists (ROPs) required for the health of the profession is estimated to be 125 per year in 2020. The radiation oncology physics community should plan to build residency programs to support these numbers for the future of the profession.

  11. TU-E-211-01: Establishing Multidisciplinary Collaboration as a Medical Physicist.

    Science.gov (United States)

    Xing, L; Fraass, B; Ford, E; Chang, S

    2012-06-01

    Many medical physicists are scientists at heart and their career fulfillment includes a balance of clinical service and research development. Multidisciplinary collaboration is a great way for the medical physicists to advance science and technology of our fields and the fields of our collaborators. Cross-pollination among scientists of different fields has been the key for some of the most significant breakthroughs in science and medicine and produced some of the most rewarding experiences for the individuals involved. However, medical physicists face unique challenges in establishing multidisciplinary collaboration because our time and resources for research are often quite limited compared to basic scientists. Yet we medical physicists are uniquely positioned and have a tremendous opportunity to create/contribute to multidisciplinary research: our fields are already multidisciplinary in nature and hospital environment is problem rich. How do we establish and carry out research collaboration with scientists of other fields? How to balance research with your higher priority clinical service? How do you find the right multidisciplinary collaboration in your own environment? We will discuss the challenges, provide real exemplary solutions to the above questions, and offer advise to medical physicists who are interested in starting or improving their multidisciplinary collaboration. There are different kinds of multidisciplinary collaborations a medical physicist can create and participate at different involvement levels. Multidisciplinary collaboration is not for every medical physicist but for those who seek and devote time to it, the experience can be truly rewarding and the impact can be enormous. 1. Learn the types of multidisciplinary collaboration medical physicists can created/participated 2. Learn the approaches and strategies to develop collaborations with scientists and professional of other fields3. Understand the challenges and different approaches to

  12. Long-term rise in geomagnetic activity - A close connection between quiet days and storms

    DEFF Research Database (Denmark)

    Vennerstrøm, Susanne

    2000-01-01

    Geomagnetic quiet days and magnetic storms are naturally believed to be due to very different solar wind conditions. In this study we however demonstrate that the long-term variation of geomagnetic quiet and disturbed days are surprisingly similar. By the use of daily averages of the geomagnetic.......7. The results indicate that the longterm,increase is due to an increase in the background solar wind parameters, rather than in the number of solar wind disturbances....

  13. Roles and Responsibilities, and Education and Training Requirements for Clinically Qualified Medical Physicists (Russian Edition)

    International Nuclear Information System (INIS)

    2014-01-01

    This publication addresses the shortfall of well trained and clinically qualified medical physicists working in radiation medicine. The roles, responsibilities and clinical training requirements of medical physicists have not always been well defined or well understood by health care professionals, health authorities and regulatory agencies. To fill this gap, this publication provides recommendations for the academic education and clinical training of clinically qualified medical physicists, including recommendations for their accreditation certification and registration, along with continuous professional development. The goal is to establish criteria that support the harmonization of education and clinical training worldwide

  14. Running quietly reduces ground reaction force and vertical loading rate and alters foot strike technique.

    Science.gov (United States)

    Phan, Xuan; Grisbrook, Tiffany L; Wernli, Kevin; Stearne, Sarah M; Davey, Paul; Ng, Leo

    2017-08-01

    This study aimed to determine if a quantifiable relationship exists between the peak sound amplitude and peak vertical ground reaction force (vGRF) and vertical loading rate during running. It also investigated whether differences in peak sound amplitude, contact time, lower limb kinematics, kinetics and foot strike technique existed when participants were verbally instructed to run quietly compared to their normal running. A total of 26 males completed running trials for two sound conditions: normal running and quiet running. Simple linear regressions revealed no significant relationships between impact sound and peak vGRF in the normal and quiet conditions and vertical loading rate in the normal condition. t-Tests revealed significant within-subject decreases in peak sound, peak vGRF and vertical loading rate during the quiet compared to the normal running condition. During the normal running condition, 15.4% of participants utilised a non-rearfoot strike technique compared to 76.9% in the quiet condition, which was corroborated by an increased ankle plantarflexion angle at initial contact. This study demonstrated that quieter impact sound is not directly associated with a lower peak vGRF or vertical loading rate. However, given the instructions to run quietly, participants effectively reduced peak impact sound, peak vGRF and vertical loading rate.

  15. Quiet Eye Training Facilitates Competitive Putting Performance in Elite Golfers

    Science.gov (United States)

    Vine, Samuel J.; Moore, Lee J.; Wilson, Mark R.

    2011-01-01

    The aim of this study was to examine the effectiveness of a brief quiet eye (QE) training intervention aimed at optimizing visuomotor control and putting performance of elite golfers under pressure, and in real competition. Twenty-two elite golfers (mean handicap 2.7) recorded putting statistics over 10 rounds of competitive golf before attending training individually. Having been randomly assigned to either a QE training or Control group, participants were fitted with an Applied Science Laboratories Mobile Eye tracker and performed 20 baseline (pre-test) putts from 10 ft. Training consisted of video feedback of their gaze behavior while they completed 20 putts; however the QE-trained group received additional instructions related to maintaining a longer QE period. Participants then recorded their putting statistics over a further 10 competitive rounds and re-visited the laboratory for retention and pressure tests of their visuomotor control and putting performance. Overall, the results were supportive of the efficacy of the QE training intervention. QE duration predicted 43% of the variance in putting performance, underlying its critical role in the visuomotor control of putting. The QE-trained group maintained their optimal QE under pressure conditions, whereas the Control group experienced reductions in QE when anxious, with subsequent effects on performance. Although their performance was similar in the pre-test, the QE-trained group holed more putts and left the ball closer to the hole on missed putts than their Control group counterparts in the pressure test. Importantly, these advantages transferred to the golf course, where QE-trained golfers made 1.9 fewer putts per round, compared to pre-training, whereas the Control group showed no change in their putting statistics. These results reveal that QE training, incorporated into a pre-shot routine, is an effective intervention to help golfers maintain control when anxious. PMID:21713182

  16. SOHO reveals violent action on the quiet Sun

    Science.gov (United States)

    1996-05-01

    SOHO's scientists are impressed by the vigorous action that they see going on every day, because the Sun is in the very quietest phase of its eleven-year cycle of activity. To ground-based observatories it appears extremely calm just now. The early indications of SOHO's performance amply justify the creation of a sungazing spacecraft capable of observing ultraviolet emissions that are blotted out by the Earth's atmosphere. Apart from the imager, two ultraviolet spectrometers and an ultraviolet coronagraph (an imager for the outer atmosphere) are busy analysing the violent processes at a wide range of wavelengths. Between them, these instruments should cure long-lasting ignorance concerning the Sun, especially about why the atmosphere is so hot and what drives the solar wind that blows non-stop into the Solar System. Scientists from other experimental teams use SOHO to explore the Sun from its deep interior to the far reaches of the solar wind. They have watched the supposedly quiet Sun belching huge masses of gas into space. They have mapped a hole burnt by the solar wind in a breeze of gas coming from the stars. And they have detected currents of gas flowing just below the visible surface. SOHO is a project of international cooperation between the European Space Agency and NASA. The spacecraft was built in Europe and instrumented by scientists on both sides of the Atlantic. NASA launched SOHO on 2 December 1995, and also provides the ground stations and an operations centre near Washington. The first results are the more remarkable because SOHO arrived at its vantage point 1,500,000 kilometres out in space only in February, and formally completed its commissioning on 16 April. It has a long life ahead of it. All scientific instruments are working well. The luminosity oscillation imager belonging to the VIRGO experiment had trouble with its lens cover. When opened, the cover rebounded on its hinges and closed again. Commands were devised that gave a shorter impulse

  17. The Many Worlds of Leo Szilard: Physicist, Peacemaker, Provocateur

    Science.gov (United States)

    Lanouette, William

    2014-03-01

    Best known for being the first to conceive and patent the nuclear chain reaction in the 1930s, Leo Szilard should also be remembered for other insights in both physics and biology, and for historical initiatives to control the A-bomb he helped create. In physics, Szilard applied entropy to data in a seminal 1929 paper that laid the basis for ``information theory.'' Szilard co-designed an electromagnetic refrigerator pump with Einstein in the 1920s, in 1939 he co-designed the first nuclear reactor with Enrico Fermi, and he later thought up and named the nuclear ``breeder'' reactor. Biologist Francois Jacob called Szilard an ``intellectual bumblebee'' for the many novel ideas he shared, including one that earned Jacob and others the Nobel Prize. James D. Watson said that for intellectual stimulation he liked being around Szilard because ``Leo got excited about something before it was true.'' A political activist, Szilard proposed and drafted the 1939 letter Einstein sent to President Franklin Roosevelt that warned of German A-bomb work and led to the Manhattan Project - where Szilard was ``Chief Physicist.'' Yet Szilard then worked tirelessly to curb nuclear weapons, organizing a scientists' petition to President Truman and lobbying Congress for civilian control of the atom. Szilard loved dreaming up new institutions. He helped to create the Pugwash Conferences on Science and World Affairs, and founded the Council for a Livable World - the first political action committee for arms control. In biology, Szilard proposed the European Molecular Biology Organization modeled on CERN, and helped create the Salk Institute for Biological Studies, where he was one of the first fellows. Shy, witty, and eccentric, Szilard wrote a political satire in 1960 that predicted when the US-Soviet nuclear arms race would end in the late 1980s. Another satire, ``My Trial as a War Criminal'' about scientists' responsibilities for weapons of mass destruction, is credited with prompting

  18. Physicists get first glimpse of antimatter: Stuff of science fiction: Canadian among group making breakthrough

    CERN Multimedia

    Munro, M

    2002-01-01

    "A team of Canadian, U.S. and European physicists, working at the CERN physics facility in Geneva, is reporting in Physical Review Letters this week that it has created and probed atoms of antihydrogen" (1 page).

  19. Black Holes Physicists could soon be creating black holes in the Laboratory

    CERN Multimedia

    Carr, Bernard

    2005-01-01

    Ever sinc physicists invented particle accelerators, nearly 80 years ago, they have used them for such exotic tasks as splitting atoms, transmuting elements, producing antimatter and creating particles not previoulsy observed in nature (7 pages)

  20. The role of physicist in the medical use of radiation and radioisotopes

    International Nuclear Information System (INIS)

    Bose, A.; Eisenlohr, H.

    1977-01-01

    The role of physicists in fields of radiotherapy and radiobiology are brought out in detail. The importance of the physicists in dose measurements, design of equipment and calculations of doses etc. is pointed out. Their responsibility in radiation protection where constant vigilance is necessary and an effort to minimise the dose with maximum benefits to the patient should always be contemplated, is also stressed. (A.K.)

  1. Working with the medical equipment: the status of the medical physicist in Romania today

    International Nuclear Information System (INIS)

    Leanca, Valeria

    2008-01-01

    Full text: The presentation will emphasize on the following points: a) General Information; b) Medical Physics activities in the following fields; c) Role of the medical physicist; d) The National Government Organization and the implementation of the status of the medical physicist working in the hospitals in Romania; e) Organizational Structure; f) Purpose; g) Aims; h) Legislation of Medical Physics; i) Medical equipment in Romania (author)

  2. A Gendered Approach to Science Ethics for US and UK Physicists.

    Science.gov (United States)

    Ecklund, Elaine Howard; Di, Di

    2017-02-01

    Some research indicates that women professionals-when compared to men-may be more ethical in the workplace. Existing literature that discusses gender and ethics is confined to the for-profit business sector and primarily to a US context. In particular, there is little attention paid to gender and ethics in science professions in a global context. This represents a significant gap, as science is a rapidly growing and global professional sector, as well as one with ethically ambiguous areas. Adopting an international comparative perspective, this paper relies on 121 semi-structured interviews with US and UK academic physicists to examine how physicists perceive the impact of gender on science ethics. Findings indicate that some US and UK physicists believe that female scientists handle ethical issues within science in a feminine way whereas their male colleagues approach ethics in a masculine way. Some of these physicists further claim that these different approaches to science ethics lead to male and female scientists' different levels of competitiveness in academic physics. In both the US and the UK, there are "gender-blind" physicists, who do not think gender is related to professional ethics. Relying on physicists' nuanced descriptions this paper contributes to the current understanding of gender and science and engineering ethics.

  3. The role of periodicity in perceiving speech in quiet and in background noise.

    Science.gov (United States)

    Steinmetzger, Kurt; Rosen, Stuart

    2015-12-01

    The ability of normal-hearing listeners to perceive sentences in quiet and in background noise was investigated in a variety of conditions mixing the presence and absence of periodicity (i.e., voicing) in both target and masker. Experiment 1 showed that in quiet, aperiodic noise-vocoded speech and speech with a natural amount of periodicity were equally intelligible, while fully periodic speech was much harder to understand. In Experiments 2 and 3, speech reception thresholds for these targets were measured in the presence of four different maskers: speech-shaped noise, harmonic complexes with a dynamically varying F0 contour, and 10 Hz amplitude-modulated versions of both. For experiment 2, results of experiment 1 were used to identify conditions with equal intelligibility in quiet, while in experiment 3 target intelligibility in quiet was near ceiling. In the presence of a masker, periodicity in the target speech mattered little, but listeners strongly benefited from periodicity in the masker. Substantial fluctuating-masker benefits required the target speech to be almost perfectly intelligible in quiet. In summary, results suggest that the ability to exploit periodicity cues may be an even more important factor when attempting to understand speech embedded in noise than the ability to benefit from masker fluctuations.

  4. Quiet Periods in Edge Turbulence Preceding the L-H Transition in NSTX

    International Nuclear Information System (INIS)

    Zweben, S.; Maqueda, R.J.; Hager, R.; Hallatschek, K.; Kaye, S.M.; Munsat, T.; Poli, F.M.; Roquemore, A.L.; Sechrest, Y.; Stotler, D.P.

    2010-01-01

    This paper describes the first observations in NSTX of 'quiet periods' in the edge turbulence preceding the L-H transition, as diagnosed by the GPI diagnostic near the outer midplane separatrix. During these quiet periods the GPI D light emission pattern was transiently similar to that seen during Hmode, i.e. with a relatively small fraction of the GPI light emission located outside the separatrix. These quiet periods had a frequency of ∼3 kHz for at least 30 msec before the L-H transition, and were correlated with changes in the direction of the local poloidal velocity. The GPI turbulence images were also analyzed to obtain an estimate for the dimensionless poloidal shearing S =(dVp/dr)(Lr/Lp). The values of S were strongly modulated by the quiet periods, but not otherwise varying for at least 30 msec preceding the L-H transition. Since neither the quiet periods nor the shear flow increased significantly immediately preceding the L-H transition, neither of these appears to be the trigger for this transition, at least for these cases in NSTX.

  5. Characterising infant inter-breath interval patterns during active and quiet sleep using recurrence plot analysis.

    Science.gov (United States)

    Terrill, Philip I; Wilson, Stephen J; Suresh, Sadasivam; Cooper, David M

    2009-01-01

    Breathing patterns are characteristically different between active and quiet sleep states in infants. It has been previously identified that breathing dynamics are governed by a non-linear controller which implies the need for a nonlinear analytical tool. Further, it has been shown that quantified nonlinear variables are different between adult sleep states. This study aims to determine whether a nonlinear analytical tool known as recurrence plot analysis can characterize breath intervals of active and quiet sleep states in infants. Overnight polysomnograms were obtained from 32 healthy infants. The 6 longest periods each of active and quiet sleep were identified and a software routine extracted inter-breath interval data for recurrence plot analysis. Determinism (DET), laminarity (LAM) and radius (RAD) values were calculated for an embedding dimension of 4, 6, 8 and 16, and fixed recurrence of 0.5, 1, 2, 3.5 and 5%. Recurrence plots exhibited characteristically different patterns for active and quiet sleep. Active sleep periods typically had higher values of RAD, DET and LAM than for quiet sleep, and this trend was invariant to a specific choice of embedding dimension or fixed recurrence. These differences may provide a basis for automated sleep state classification, and the quantitative investigation of pathological breathing patterns.

  6. A quiet leader unites researchers in drive for the next big machine

    CERN Multimedia

    Cho, Adrian

    2006-01-01

    "As head of the design team for the international linear collider, Barry Barish has physicists around the globe putting together. But can the governements ot the world afford their enormous particle smasher?" (2 pages)

  7. Educational outcomes of a medical physicist program over the past 10 years in Japan

    International Nuclear Information System (INIS)

    Kadoya, Noriyuki; Karasawa, Kumiko; Sumida, Iori; Arimura, Hidetaka; Kakinohana, Yasumasa; Kabuki, Shigeto; Monzen, Hajime; Nishio, Teiji; Shirato, Hiroki; Yamada, Syogo

    2017-01-01

    The promotion plan for the Platform of Human Resource Development for Cancer (Ganpro) was initiated by the Ministry of Education, Culture, Sports, Science and Technology of Japan in 2007, establishing a curriculum for medical physicists. In this study, we surveyed the educational outcomes of the medical physicist program over the past 10 years since the initiation of Ganpro. The Japan Society of Medical Physics mailing list was used to announce this survey. The questionnaire was created by members of the Japanese Board for Medical Physicist Qualification, and was intended for the collection of information regarding the characteristics and career paths of medical physics students. Students who participated in the medical physics program from 2007 to 2016 were enrolled. Thirty-one universities (17 accredited and 14 non-accredited) were represented in the survey. In total, 491, 105 and 6 students were enrolled in the Master's, Doctorate and Residency programs, respectively. Most students held a Bachelor's degree in radiological technology (Master's program, 87%; Doctorate program, 72%). A large number of students with a Master's degree worked as radiological technologists (67%), whereas only 9% (n = 32) worked as medical physicists. In contrast, 53% (n = 28) of the students with a Doctorate degree worked as medical physicists. In total, 602 students (from 31 universities) completed the survey. Overall, although the number of the graduates who worked as medical physicists was small, this number increased annually. It thus seems that medical institutions in Japan are recognizing the necessity of licensed medical physicists in the radiotherapy community.

  8. Clinical Training of Medical Physicists Specializing in Nuclear Medicine (Spanish Edition)

    International Nuclear Information System (INIS)

    2013-01-01

    The application of radiation in human health, for both diagnosis and treatment of disease, is an important component of the work of the IAEA. The responsibility for the increasingly technical aspects of this work is undertaken by the medical physicist. To ensure good practice in this vital area, structured clinical training programmes are required to complement academic learning. This publication is intended to be a guide to the practical implementation of such a programme for nuclear medicine. There is a general and growing awareness that radiation medicine is increasingly dependent on well trained medical physicists who are based in a clinical setting. However an analysis of the availability of medical physicists indicates a large shortfall of qualified and capable professionals. This is particularly evident in developing countries. While strategies to increase educational opportunities are critical to such countries, the need for guidance on structured clinical training was recognized by the members of the Regional Cooperative Agreement for Research, Development and Training related to Nuclear Science and Technology (RCA) for the Asia-Pacific region. Consequently, a technical cooperation regional project (RAS6038) under the RCA programme was formulated to address this need in this region by developing suitable material and establishing its viability. Development of a clinical training guide for medical physicists specialising in nuclear medicine was started in 2009 with the appointment of a core drafting committee of regional and international experts. The publication drew on the experience of clinical training in Australia, Croatia and Sweden and was moderated by physicists working in the Asian region. The present publication follows the approach of earlier IAEA publications in the Training Course Series, specifically Nos 37 and 47, Clinical Training of Medical Physicists Specializing in Radiation Oncology and Clinical Training of Medical Physicists

  9. Clinical Training of Medical Physicists Specializing in Nuclear Medicine (French Edition)

    International Nuclear Information System (INIS)

    2012-01-01

    The application of radiation in human health, for both diagnosis and treatment of disease, is an important component of the work of the IAEA. The responsibility for the increasingly technical aspects of this work is undertaken by the medical physicist. To ensure good practice in this vital area, structured clinical training programmes are required to complement academic learning. This publication is intended to be a guide to the practical implementation of such a programme for nuclear medicine. There is a general and growing awareness that radiation medicine is increasingly dependent on well trained medical physicists who are based in a clinical setting. However an analysis of the availability of medical physicists indicates a large shortfall of qualified and capable professionals. This is particularly evident in developing countries. While strategies to increase educational opportunities are critical to such countries, the need for guidance on structured clinical training was recognized by the members of the Regional Cooperative Agreement for Research, Development and Training related to Nuclear Science and Technology (RCA) for the Asia-Pacific region. Consequently, a technical cooperation regional project (RAS6038) under the RCA programme was formulated to address this need in this region by developing suitable material and establishing its viability. Development of a clinical training guide for medical physicists specialising in nuclear medicine was started in 2009 with the appointment of a core drafting committee of regional and international experts. The publication drew on the experience of clinical training in Australia, Croatia and Sweden and was moderated by physicists working in the Asian region. The present publication follows the approach of earlier IAEA publications in the Training Course Series, specifically Nos 37 and 47, Clinical Training of Medical Physicists Specializing in Radiation Oncology and Clinical Training of Medical Physicists

  10. Quiet Ego, Self-Regulatory Skills, and Perceived Stress in College Students.

    Science.gov (United States)

    Wayment, Heidi A; Cavolo, Keragan

    2018-04-13

    Examine the unique contributions of self-control and grit subscales (perseverance, interest consistency) as potential mediators of the relationship between quiet ego characteristics and less perceived stress in college students. Data from 1117 college students were collected between October, 2015 and May, 2016. The sample was split randomly into exploratory and confirmatory samples. Multiple mediator models were tested with PROCESS module (SPSS v. 24) in both samples. Hypotheses were largely confirmed with self-control fully mediating the link between quiet ego and perceived stress in both samples. Although many self-regulatory constructs may argue for their positive impact on college student outcomes, interventions that strengthen self-control, and not grit, may be most promising to reduce perceived stress. Further, interventions to strengthen quiet ego characteristics may be beneficial for strengthening self-control in college students.

  11. Spectroscopic and polarimetric study of radio-quiet weak emission line quasars

    Science.gov (United States)

    Kumar, Parveen; Chand, Hum; Gopal-Krishna; Srianand, Raghunathan; Stalin, Chelliah Subramonian; Petitjean, Patrick

    2018-04-01

    A small subset of optically selected radio-quiet QSOs with weak or no emission lines may turn out to be the elusive radio-quiet BL Lac objects, or simply be radio-quiet QSOs with an infant/shielded broad line region (BLR). High polarisation (p > 3-4%), a hallmark of BL Lacs, can be used to test whether some optically selected ‘radio-quiet weak emission line QSOs’ (RQWLQs) show a fractional polarisation high enough to qualify as radio-quiet analogues of BL Lac objects. To check this possibility, we have made optical spectral and polarisation measurements of a sample of 19 RQWLQs. Out of these, only 9 sources show a non-significant proper motion (hence very likely extragalactic) and only two of them are found to have p > 1%. For these two RQWLQs, namely J142505.59+035336.2 and J154515.77+003235.2, we found the highest polarization to be 1.59±0.53%, which is again too low to classify them as (radio-quiet) BL Lacs, although one may recall that even genuine BL Lacs sometimes appear weakly polarised. We also present a statistical comparison of the optical spectral index, for a sample of 45 RQWLQs with redshift-luminosity matched control samples of 900 QSOs and an equivalent sample of 120 blazars, assembled from the literature. The spectral index distribution of RQWLQs is found to differ, at a high significance level, from that of blazars. This, too, is consistent with the common view that the mechanism of the central engine in RQWLQs, as a population, is close to that operating in normal QSOs and the primary difference between them is related to the BLR.

  12. Vowel and tone recognition in quiet and in noise among Mandarin-speaking amusics.

    Science.gov (United States)

    Tang, Wei; Wang, Xi-Jian; Li, Jia-Qi; Liu, Chang; Dong, Qi; Nan, Yun

    2018-03-06

    Music and language are two intricately linked communication modalities in humans. A deficit in music pitch processing as manifested in the condition of congenital amusia has been related to difficulties in lexical tone processing for both tone and non-tonal languages. However, it is still unclear whether amusia also affects the perception of vowel phonemes in quiet and in noise. In this study, we examined vowel-plus-tone identification in quiet and noise conditions among Mandarin-speaking amusics with and without speech tone difficulties (tone agnosics and pure amusics, respectively), and IQ- and age-matched controls. Overall, pure amusics showed vowel and tone identification comparable to the controls in both quiet and noise conditions. Compared to pure amusics and controls, tone agnosics showed deficits in tone perception in both quiet and noise conditions. More importantly, their vowel perception was lower than pure amusics and controls in noise conditions, e.g., at a signal-to-noise ratio of -4 dB, although they showed normal-like performance in quiet and at a signal-to-noise ratio of -8 dB. These results suggest that when amusia affected speech tone processing (e.g., tone agnosics), it could also compromise vowel processing in noise. However, amusia alone does not affect tone or vowel perception in Mandarin Chinese either in quiet or in noise. Overall, the current study highlights the necessity of taking heterogeneity within the amusic group into account when considering the related speech deficits in this group. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. The second physicist on the history of theoretical physics in germany

    CERN Document Server

    Jungnickel, Christa

    2017-01-01

    This book explores the rise of theoretical physics in 19th century Germany. The authors show how the junior second physicist in German universities over time became the theoretical physicist, of equal standing to the experimental physicist. Gustav Kirchhoff, Hermann von Helmholtz, and Max Planck are among the great German theoretical physicists whose work and career are examined in this book. Physics was then the only natural science in which theoretical work developed into a major teaching and research specialty in its own right. Readers will discover how German physicists arrived at a well-defined field of theoretical physics with well understood and generally accepted goals and needs. The authors explain the nature of the work of theoretical physics with many examples, taking care always to locate the research within the workplace. The book is a revised and shortened version of Intellectual Mastery of Nature: Theoretical Physics from Ohm to Einstein, a two-volume work by the same authors. This new edition ...

  14. Code of Ethics for the American Association of Physicists in Medicine: report of Task Group 109.

    Science.gov (United States)

    Serago, Christopher F; Adnani, Nabil; Bank, Morris I; BenComo, Jose A; Duan, Jun; Fairobent, Lynne; Freedman, D Jay; Halvorsen, Per H; Hendee, William R; Herman, Michael G; Morse, Richard K; Mower, Herbert W; Pfeiffer, Douglas E; Root, William J; Sherouse, George W; Vossler, Matthew K; Wallace, Robert E; Walters, Barbara

    2009-01-01

    A comprehensive Code of Ethics for the members of the American Association of Physicists in Medicine (AAPM) is presented as the report of Task Group 109 which consolidates previous AAPM ethics policies into a unified document. The membership of the AAPM is increasingly diverse. Prior existing AAPM ethics polices were applicable specifically to medical physicists, and did not encompass other types of members such as health physicists, regulators, corporate affiliates, physicians, scientists, engineers, those in training, or other health care professionals. Prior AAPM ethics policies did not specifically address research, education, or business ethics. The Ethics Guidelines of this new Code of Ethics have four major sections: professional conduct, research ethics, education ethics, and business ethics. Some elements of each major section may be duplicated in other sections, so that readers interested in a particular aspect of the code do not need to read the entire document for all relevant information. The prior Complaint Procedure has also been incorporated into this Code of Ethics. This Code of Ethics (PP 24-A) replaces the following AAPM policies: Ethical Guidelines for Vacating a Position (PP 4-B); Ethical Guidelines for Reviewing the Work of Another Physicist (PP 5-C); Guidelines for Ethical Practice for Medical Physicists (PP 8-D); and Ethics Complaint Procedure (PP 21-A). The AAPM Board of Directors approved this Code or Ethics on July 31, 2008.

  15. History and development of medical physics and medical physicist in Japan

    International Nuclear Information System (INIS)

    Toyofuku, F.

    2014-01-01

    The history of medical physics in Japan dates back to the mid-1950's when radioisotope sources such as cobalt-60 were initiated into hospitals. In 1961, a total of about 30 medical physics researchers created a sub-committee of medical physics under the Japan Radiological Society (JRS), which flourished throughout the decade, and the number of members exceeded to more than 200 in 1970. Although there were great advances in medical technologies, the number of members of the medical physics community did not grow for the next two decades from 1980 to 2000. Then, the JRS began to officially recognize medical physicists as a professional group in 1987. Qualifications of candidacy for the examination included having the education equivalent of a Bachelor of Science/Engineering and being a member of the JRS. For the first official examination, 70 medical physicists were approved by the JRS. As of 2013, there are currently 700 medical physicists, however, the number of practicing clinical medical physicists remains only about 150. The main reason for this limited number of medical physicists is that the certification is not recognized as a national license and therefore is challenging to find professional employment as qualified medical personnel at hospitals. (author)

  16. Magnetic Field Perturbations from Currents in the Dark Polar Regions During Quiet Geomagnetic Conditions

    DEFF Research Database (Denmark)

    Friis-Christensen, Eigil; Finlay, Chris; Hesse, M.

    2017-01-01

    In the day-side sunlit polar ionosphere the varying and IMF dependent convection creates strong ionospheric currents even during quiet geomagnetic conditions. Observations during such times are often excluded when using satellite data to model the internal geomagneticmain field. Observations from...... the night-side or local winter during quiet conditions are, however, also influenced by variations in the IMF. In this paper we briefly review the large scale features of the ionospheric currents in the polar regions with emphasis on the current distribution during undisturbed conditions. We examine...

  17. Prediction of IOI-HA Scores Using Speech Reception Thresholds and Speech Discrimination Scores in Quiet

    DEFF Research Database (Denmark)

    Brännström, K Jonas; Lantz, Johannes; Nielsen, Lars Holme

    2014-01-01

    ), and speech discrimination scores (SDSs) in quiet or in noise are common assessments made prior to hearing aid (HA) fittings. It is not known whether SRT and SDS in quiet relate to HA outcome measured with the International Outcome Inventory for Hearing Aids (IOI-HA). PURPOSE: The aim of the present study...... COLLECTION AND ANALYSIS: The psychometric properties were evaluated and compared to previous studies using the IOI-HA. The associations and differences between the outcome scores and a number of descriptive variables (age, gender, fitted monaurally/binaurally with HA, first-time/experienced HA users, years...

  18. "Quiet Food Sovereignty” as Food Sovereignty without Movements? Understanding Food Sovereignty in Post-Socialist Russia

    OpenAIRE

    Visser, Oane; Mamonova, Natalia; Spoor, Max; Nikulin, Alexander

    2017-01-01

    textabstractWhat does food sovereignty look like in settings where rural social movements are weak or non-existent, such as in countries with post-socialist, semi-authoritarian regimes? Focusing on Russia, we present a divergent form of food sovereignty. Building on the concept of ‘quiet sustainability’, we present a dispersed, muted, but clearly bottom-up variant we term ‘quiet food sovereignty’. In the latter, the role of the very productive smallholdings is downplayed by the state and part...

  19. The Mental Aftermath - The Mentality of German Physicists 1945-1949

    Science.gov (United States)

    Hentschel, Klaus

    2007-01-01

    Few scientific communities have been more thoroughly studied than 20th-century German physicists. Yet their behavior and patterns of thinking immediately after the war remains puzzling. During the first five postwar years they suspended their internecine battles and a strange solidarity emerged. Former enemies were suddenly willing to exonerate each other blindly and even morally upright physicists began to write tirades against the 'denazification mischief' or the 'export of scientists'. Personal idiosyncracies melded into a strangely uniform pattern of rejection or resistance to the Allied occupiers, with attendant repressed feelings and self-pity. Politics was once again perceived as remote, dirty business. It was feared that the least concession of guilt would bring down even more severe sanctions on their discipline. Using tools from the history of mentality, such as analysis of serial publications, these tendenciesare examined. The perspective of emigre physicists, as reflected in their private letters and reports, embellish this portrait.

  20. WE-G-19A-01: Radiologists and Medical Physicists: Working Together to Achieve Common Goals

    Energy Technology Data Exchange (ETDEWEB)

    Jones, A; Ma, J; Steele, J; Choi, H [UT MD Anderson Cancer Center, Houston, TX (United States)

    2014-06-15

    It is vitally important that medical physicists understand the clinical questions that radiologists are trying to answer with patient images. Knowledge of the types of information the radiologist needs helps medical physicists configure imaging protocols that appropriately balance radiation dose, time, and image quality. The ability to communicate with radiologists and understand medical terminology, anatomy, and physiology is key to creating such imaging protocols. In this session, radiologists will present clinical cases and describe the information they are seeking in the clinical images. Medical physicists will then discuss how imaging protocols are configured. Learning Objectives: Understand the types of information that radiologists seek in medical images. Apply this understanding in configuring the imaging equipment to deliver this information. Develop strategies for working with physician colleagues.

  1. A questionnaire survey of medical physicist and quality manager for radiation therapy

    International Nuclear Information System (INIS)

    Nishio, Teiji; Ashino, Yasuo; Onishi, Hiroshi

    2008-01-01

    A questionnaire survey of medical physicists and quality managers for radiation therapy was performed by the Japanese Society for Therapeutic Radiology and Oncology (JASTRO) Future Planning Committee. We mailed the questionnaire to 726 radiotherapy facilities with the answers returned from 353 radiotherapy facilities. The result showed 178 facilities were staffed by radiotherapy workers who were licensed medical physicists or quality managers. A staff of 289 was licensed radiotherapy workers. Most of the staff were radiotherapy technologists. Quality control for radiation therapy was rated satisfactory according to each facility's assessment. Radiation therapy of high quality requires continued education of medical physicists and quality managers, in addition to keeping up with times for quality control. (author)

  2. Paul Baillon presents the book "Differential manifolds: a basic approach for experimental physicists" | 25 March

    CERN Multimedia

    CERN Library

    2014-01-01

    Tuesday 25 March 2014 at 4 p.m. in the Library, bldg. 52-1-052 "Differential manifolds: a basic approach for experimental physicists" by Paul Baillon,  World Scientific, 2013, ISBN 978-981-4449-56-4. Differential manifold is the framework of particle physics and astrophysics nowadays. It is important for all research physicists to be accustomed to it, and even experimental physicists should be able to manipulate equations and expressions in this framework. This book gives a comprehensive description of the basics of differential manifold with a full proof of elements. A large part of the book is devoted to the basic mathematical concepts, which are all necessary for the development of the differential manifold. This book is self-consistent; it starts from first principles. The mathematical framework is the set theory with its axioms and its formal logic. No special knowledge is needed. Coffee will be served from 3.30 p.m.

  3. WE-G-19A-01: Radiologists and Medical Physicists: Working Together to Achieve Common Goals

    International Nuclear Information System (INIS)

    Jones, A; Ma, J; Steele, J; Choi, H

    2014-01-01

    It is vitally important that medical physicists understand the clinical questions that radiologists are trying to answer with patient images. Knowledge of the types of information the radiologist needs helps medical physicists configure imaging protocols that appropriately balance radiation dose, time, and image quality. The ability to communicate with radiologists and understand medical terminology, anatomy, and physiology is key to creating such imaging protocols. In this session, radiologists will present clinical cases and describe the information they are seeking in the clinical images. Medical physicists will then discuss how imaging protocols are configured. Learning Objectives: Understand the types of information that radiologists seek in medical images. Apply this understanding in configuring the imaging equipment to deliver this information. Develop strategies for working with physician colleagues

  4. SU-B-BRA-00: The Medical Physicist Value Proposition for Tomorrow and Today

    International Nuclear Information System (INIS)

    Sherouse, G.

    2016-01-01

    In the current rapidly changing Healthcare environment, many groups are competing for limited resources. How can medical physicists position themselves to be a relevant stakeholder in the discussion of how those resources are allocated Our value goes beyond what can be shown in a business plan and is heavily involved with safety and quality. Three areas will be explored: What is our value? Who needs to receive that message? How do we communicate that message? To help frame the discussion in terms of how other stakeholders may view the value of medical physicists, a physician and an administrator will present their perspective. Lastly, a multidisciplinary panel will present real life examples of strategies that can be utilized today to establish the value of medical physicists. The presentation of these examples will lead into an interactive question and answer time. V. Willcut, I work for Elekta. There was no research associated with this talk.

  5. A survey of Canadian medical physicists: software quality assurance of in-house software.

    Science.gov (United States)

    Salomons, Greg J; Kelly, Diane

    2015-01-05

    This paper reports on a survey of medical physicists who write and use in-house written software as part of their professional work. The goal of the survey was to assess the extent of in-house software usage and the desire or need for related software quality guidelines. The survey contained eight multiple-choice questions, a ranking question, and seven free text questions. The survey was sent to medical physicists associated with cancer centers across Canada. The respondents to the survey expressed interest in having guidelines to help them in their software-related work, but also demonstrated extensive skills in the area of testing, safety, and communication. These existing skills form a basis for medical physicists to establish a set of software quality guidelines.

  6. A survey of Canadian medical physicists: software quality assurance of in‐house software

    Science.gov (United States)

    Kelly, Diane

    2015-01-01

    This paper reports on a survey of medical physicists who write and use in‐house written software as part of their professional work. The goal of the survey was to assess the extent of in‐house software usage and the desire or need for related software quality guidelines. The survey contained eight multiple‐choice questions, a ranking question, and seven free text questions. The survey was sent to medical physicists associated with cancer centers across Canada. The respondents to the survey expressed interest in having guidelines to help them in their software‐related work, but also demonstrated extensive skills in the area of testing, safety, and communication. These existing skills form a basis for medical physicists to establish a set of software quality guidelines. PACS number: 87.55.Qr PMID:25679168

  7. Dr. Inside and Dr. Outside: Physicists Involved With National Security and Foreign Policy

    Science.gov (United States)

    Zimmerman, Peter D.

    2009-05-01

    Physicists have had a special interest in American national security and arms control since at least the Manhattan Project. They have served our country in uniform and in the career civil service. Some have left academic careers for brief periods to work as political appointees, consultants, or resident scholars and then returned to an academic life, but often with changed goals. Some have tried government life and left nearly immediately, while others dipped a toe in and decided to stay. I will look at real-life examples, mostly using real names, drawn from my career and circle of colleagues to try to explain why some physicists have been extremely successful, why others have not, and what happens to a physicist who moved to Washington and decides to stay. I will also discuss routes into public service for those interesting in giving it a try.

  8. SU-B-BRA-00: The Medical Physicist Value Proposition for Tomorrow and Today

    Energy Technology Data Exchange (ETDEWEB)

    Sherouse, G. [Landauer Medical Physics, Glenwood, IL (United States)

    2016-06-15

    In the current rapidly changing Healthcare environment, many groups are competing for limited resources. How can medical physicists position themselves to be a relevant stakeholder in the discussion of how those resources are allocated Our value goes beyond what can be shown in a business plan and is heavily involved with safety and quality. Three areas will be explored: What is our value? Who needs to receive that message? How do we communicate that message? To help frame the discussion in terms of how other stakeholders may view the value of medical physicists, a physician and an administrator will present their perspective. Lastly, a multidisciplinary panel will present real life examples of strategies that can be utilized today to establish the value of medical physicists. The presentation of these examples will lead into an interactive question and answer time. V. Willcut, I work for Elekta. There was no research associated with this talk.

  9. Clinical Training of Medical Physicists Specializing in Diagnostic Radiology (French Edition)

    International Nuclear Information System (INIS)

    2012-01-01

    The application of radiation in human health, for both diagnosis and treatment of disease, is an important component of the work of the IAEA. The responsibility for the increasing technical aspects of this work is undertaken by the medical physicist. To ensure good practice in this vital area, structured clinical training programmes are required to complement academic learning. This publication is intended to be a guide to the practical implementation of such a programme for diagnostic radiology. There is a general and growing awareness that radiation medicine is increasingly dependent on well trained medical physicists based in the clinical setting. However, an analysis of the availability of medical physicists indicates a large shortfall of qualified and capable professionals. This is particularly evident in developing countries. While strategies to increase academic educational opportunities are critical to such countries, the need for guidance on structured clinical training was recognized by the members of the Regional Cooperative Agreement (RCA) for Research, Development and Training related to Nuclear Sciences for Asia and the Pacific. Consequently, a technical cooperation regional project (RAS6038) under the RCA programme was formulated to address this need in the Asia-Pacific region by developing suitable material and establishing its viability. Development of a clinical training guide for medical physicists specializing in diagnostic radiology started in 2007 with the appointment of a core drafting committee of regional and international experts. The publication drew on the experiences of clinical training programmes in Australia and New Zealand, the UK and the USA, and was moderated by physicists working in the Asian region. This publication follows the approach of the IAEA publication Training Course Series No. 37, Clinical Training of Medical Physicists specializing in Radiation Oncology. This approach to clinical training has been successfully tested

  10. Clinical Training of Medical Physicists Specializing in Diagnostic Radiology (Spanish Edition)

    International Nuclear Information System (INIS)

    2013-01-01

    The application of radiation in human health, for both diagnosis and treatment of disease, is an important component of the work of the IAEA. The responsibility for the increasing technical aspects of this work is undertaken by the medical physicist. To ensure good practice in this vital area, structured clinical training programmes are required to complement academic learning. This publication is intended to be a guide to the practical implementation of such a programme for diagnostic radiology. There is a general and growing awareness that radiation medicine is increasingly dependent on well trained medical physicists based in the clinical setting. However, an analysis of the availability of medical physicists indicates a large shortfall of qualified and capable professionals. This is particularly evident in developing countries. While strategies to increase academic educational opportunities are critical to such countries, the need for guidance on structured clinical training was recognized by the members of the Regional Cooperative Agreement (RCA) for Research, Development and Training related to Nuclear Sciences for Asia and the Pacific. Consequently, a technical cooperation regional project (RAS6038) under the RCA programme was formulated to address this need in the Asia-Pacific region by developing suitable material and establishing its viability. Development of a clinical training guide for medical physicists specializing in diagnostic radiology started in 2007 with the appointment of a core drafting committee of regional and international experts. The publication drew on the experiences of clinical training programmes in Australia and New Zealand, the UK and the USA, and was moderated by physicists working in the Asian region. This publication follows the approach of the IAEA publication Training Course Series No. 37, Clinical Training of Medical Physicists specializing in Radiation Oncology. This approach to clinical training has been successfully tested

  11. A century of nuclear science. Important contributions of early generation Chinese physicist to nuclear science

    International Nuclear Information System (INIS)

    Zheng Chunkai; Xu Furong

    2003-01-01

    The great discoveries and applications of nuclear science have had tremendous impact on the progress and development of mankind over the last 100 years. In the 1920's to 1940's, many young Chinese who yearned to save the country through science and education went to west Europe and north America to study science, including physics. Studying and working with famous physicists throughout the world, they made many important contributions and discoveries in the development of nuclear science. This paper describes the historical contributions of the older generation of Chinese physicists to nuclear science

  12. Quantum field theory I: Basics in mathematics and physics. A bridge between mathematicians and physicists

    International Nuclear Information System (INIS)

    Zeidler, Eberhard

    2009-01-01

    This is the first volume of a modern introduction to quantum field theory which addresses both mathematicians and physicists, at levels ranging from advanced undergraduate students to professional scientists. The book bridges the acknowledged gap between the different languages used by mathematicians and physicists. For students of mathematics the author shows that detailed knowledge of the physical background helps to motivate the mathematical subjects and to discover interesting interrelationships between quite different mathematical topics. For students of physics, fairly advanced mathematics is presented, which goes beyond the usual curriculum in physics. (orig.)

  13. Quantum field theory II: quantum electrodynamics. A bridge between mathematicians and physicists

    International Nuclear Information System (INIS)

    Zeidler, Eberhard

    2009-01-01

    This is the second volume of a modern introduction to quantum field theory which addresses both mathematicians and physicists ranging from advanced undergraduate students to professional scientists. This book seeks to bridge the existing gap between the different languages used by mathematicians and physicists. For students of mathematics it is shown that detailed knowledge of the physical background helps to discover interesting interrelationships between quite diverse mathematical topics. For students of physics fairly advanced mathematics, beyond that included in the usual curriculum in physics, is presented. The present volume concerns a detailed study of the mathematical and physical aspects of the quantum theory of light. (orig.)

  14. Quantum field theory I: Basics in mathematics and physics. A bridge between mathematicians and physicists

    Energy Technology Data Exchange (ETDEWEB)

    Zeidler, Eberhard [Max-Planck-Institut fuer Mathematik in den Naturwissenschaften, Leipzig (Germany)

    2009-07-01

    This is the first volume of a modern introduction to quantum field theory which addresses both mathematicians and physicists, at levels ranging from advanced undergraduate students to professional scientists. The book bridges the acknowledged gap between the different languages used by mathematicians and physicists. For students of mathematics the author shows that detailed knowledge of the physical background helps to motivate the mathematical subjects and to discover interesting interrelationships between quite different mathematical topics. For students of physics, fairly advanced mathematics is presented, which goes beyond the usual curriculum in physics. (orig.)

  15. Quantum field theory II: quantum electrodynamics. A bridge between mathematicians and physicists

    Energy Technology Data Exchange (ETDEWEB)

    Zeidler, Eberhard [Max Planck Institute for Mathematics in the Sciences, Leipzig (Germany)

    2009-07-01

    This is the second volume of a modern introduction to quantum field theory which addresses both mathematicians and physicists ranging from advanced undergraduate students to professional scientists. This book seeks to bridge the existing gap between the different languages used by mathematicians and physicists. For students of mathematics it is shown that detailed knowledge of the physical background helps to discover interesting interrelationships between quite diverse mathematical topics. For students of physics fairly advanced mathematics, beyond that included in the usual curriculum in physics, is presented. The present volume concerns a detailed study of the mathematical and physical aspects of the quantum theory of light. (orig.)

  16. Contributions to naive quantum mechanics. A textbook for mathematicians and physicists

    International Nuclear Information System (INIS)

    Kohlmann, Martin

    2009-01-01

    The present text examplifies by means of 60 citations from current textbooks for the study of physics the necessarity of a mathematically rigorous formulation of quantum mechanics. Well known statements of many physicists about quantum mechanics at their mathematical tool kit are commented in form of a dialogue und mathematical points of view. Supplemented are the representations by a selection of theorems of higher analysis relevant for quantum theory. The book applies to mathematicians and mathematically interested physicists or students with founded mathematical knowledge.

  17. Curriculum for education and training of Medical Physicists in Nuclear Medicine

    DEFF Research Database (Denmark)

    Del Guerra, Alberto; Bardies, Manuel; Belcari, Nicola

    2013-01-01

    and Competence approach along the lines recommended by the European Qualifications Framework. The minimum level expected in each topic in the theoretical knowledge and practical experience sections is intended to bring trainees up to the requirements expected of a Medical Physicist entering the field of Nuclear...... Medicine. CONCLUSIONS: This new joint EANM/EFOMP European guideline curriculum is a further step to harmonise specialist training of Medical Physicists in Nuclear Medicine within Europe. It provides a common framework for national Medical Physics societies to develop or benchmark their own curricula....... The responsibility for the implementation and accreditation of these standards and guidelines resides within national training and regulatory bodies....

  18. From falling bodies to radio waves classical physicists and their discoveries

    CERN Document Server

    Segrè, Emilio

    1984-01-01

    Meet a diverse group of highly original thinkers and learn about their lives and achievements: Galileo, a founding father of astronomy and physics; Christiaan Huygens, a seventeenth-century pioneer of wave-particle duality; and Isaac Newton, the English mathematician and physicist who laid the groundwork for a scientific revolution and promoted radical investigation as the means to reveal nature's hidden workings.This chronicle of physics and physicists traces the development of scientific thought from these originators to their successors, among them Faraday, Watts, Helmholtz, Maxwell, Boltzm

  19. On a possible mechanism of quasi periodic pulses of the quiet Sun decametric radio emission

    International Nuclear Information System (INIS)

    Levin, B.N.; Snegireva, S.D.

    1983-01-01

    The observed fluctuations of the quiet Sun decametric radio emission are interpreted on the basis of the plasma mechanism of generation. These fluctuations may be caused by modulation of the optical depth of the radio source due to propagation of the sound wave packet through the corona

  20. The quiet time structure of energetic (35--560 keV) radiation belt electrons

    International Nuclear Information System (INIS)

    Lyons, L.R.; Williams, D.J.

    1975-01-01

    Detailed Explorer 45 equatorial observations of the quiet time structure of radiation belt electrons (35--560 keV) for 1.7approximately-less-thanLapproximately-less-than5.2 are presented. Throughout the slot region and outer regions of the plasmasphere the observed pitch angle distributions are found to agree with those expected from resonant interactions with the plasmaspheric whistler mode wave band. Coulomb collisions become the dominant loss mechanism within the inner zone. The overall two-zone structure of the observed radial profiles is found to agree with the equilibrium structure expected to result from a balance between pitch angle scattering losses and radial diffusion from an average outer zone source. This agreement suggests that the dominant quiet time source and loss mechanisms have been identified and evaluated for energetic radiation belt electrons within the plasmasphere. In the outer regions of the plasmasphere (Lapprox.5) the equilibrium structure is observed to be modified by daily flux variations associated with changes in the level of magnetic activity that occur even during relatively quiet times. Within the inner region of the plasmasphere (Lapproximately-less-than3.5), electron fluxes are decoupled from these magnetic activity variations by the long time scales (>10 days) required for pitch angle and radial diffusion. Consequently, fluxes of these electrons are observed to remain nearly constant at equilibrium levels throughout the quiet periods examined

  1. Effects of road traffic noise and the benefit of access to quietness

    Science.gov (United States)

    Öhrström, E.; Skånberg, A.; Svensson, H.; Gidlöf-Gunnarsson, A.

    2006-08-01

    Socio-acoustic surveys were carried out as part of the Soundscape Support to Health research programme to assess the health effects of various soundscapes in residential areas. The study was designed to test whether having access to a quiet side of one's dwelling enhances opportunities for relaxation and reduces noise annoyance and other adverse health effects related to noise. The dwellings chosen were exposed to sound levels from road traffic ranging from about L=45-68 dB at the most-exposed side. The study involved 956 individuals aged 18-75 years. The results demonstrate that access to quiet indoor and outdoor sections of one's dwelling supports health; it produces a lower degree and extent of annoyance and disturbed daytime relaxation, improves sleep and contributes to physiological and psychological well-being. Having access to a quiet side of one's dwelling reduces disturbances by an average of 30-50% for the various critical effects, and corresponds to a reduction in sound levels of ( LAeq,24h) 5 dB at the most-exposed side. To protect most people (80%) from annoyance and other adverse effects, sound levels from road traffic should not exceed ( LAeq,24h) 60 dB at the most-exposed side, even if there is access to a quiet side of one's dwelling ( LAeq,24h⩽45 dB).

  2. Boundary-Layer Instability Measurements in a Mach-6 Quiet Tunnel

    Science.gov (United States)

    Berridge, Dennis C.; Ward, Christopher, A. C.; Luersen, Ryan P. K.; Chou, Amanda; Abney, Andrew D.; Schneider, Steven P.

    2012-01-01

    Several experiments have been performed in the Boeing/AFOSR Mach-6 Quiet Tunnel at Purdue University. A 7 degree half angle cone at 6 degree angle of attack with temperature-sensitive paint (TSP) and PCB pressure transducers was tested under quiet flow. The stationary crossflow vortices appear to break down to turbulence near the lee ray for sufficiently high Reynolds numbers. Attempts to use roughness elements to control the spacing of hot streaks on a flared cone in quiet flow did not succeed. Roughness was observed to damp the second-mode waves in areas influenced by the roughness, and wide roughness spacing allowed hot streaks to form between the roughness elements. A forward-facing cavity was used for proof-of-concept studies for a laser perturber. The lowest density at which the freestream laser perturbations could be detected was 1.07 x 10(exp -2) kilograms per cubic meter. Experiments were conducted to determine the transition characteristics of a streamwise corner flow at hypersonic velocities. Quiet flow resulted in a delayed onset of hot streak spreading. Under low Reynolds number flow hot streak spreading did not occur along the model. A new shock tube has been built at Purdue. The shock tube is designed to create weak shocks suitable for calibrating sensors, particularly PCB-132 sensors. PCB-132 measurements in another shock tube show the shock response and a linear calibration over a moderate pressure range.

  3. The Abnormal Quiet Days in SQ(H) in Mid and Low Latitudes Regions

    African Journals Online (AJOL)

    From the analysis and study of abnormal quiet days (AQDs) at mid and low latitudes locations, it was found that there is difference between the characteristics of phase variability Sq (H) of the low latitude locations. This suggests that the origin and cause of AQDs are of different sources in the two latitude regions. The AQDs ...

  4. Shhh… I Need Quiet! Children's Understanding of American, British, and Japanese-accented English Speakers.

    Science.gov (United States)

    Bent, Tessa; Holt, Rachael Frush

    2018-02-01

    Children's ability to understand speakers with a wide range of dialects and accents is essential for efficient language development and communication in a global society. Here, the impact of regional dialect and foreign-accent variability on children's speech understanding was evaluated in both quiet and noisy conditions. Five- to seven-year-old children ( n = 90) and adults ( n = 96) repeated sentences produced by three speakers with different accents-American English, British English, and Japanese-accented English-in quiet or noisy conditions. Adults had no difficulty understanding any speaker in quiet conditions. Their performance declined for the nonnative speaker with a moderate amount of noise; their performance only substantially declined for the British English speaker (i.e., below 93% correct) when their understanding of the American English speaker was also impeded. In contrast, although children showed accurate word recognition for the American and British English speakers in quiet conditions, they had difficulty understanding the nonnative speaker even under ideal listening conditions. With a moderate amount of noise, their perception of British English speech declined substantially and their ability to understand the nonnative speaker was particularly poor. These results suggest that although school-aged children can understand unfamiliar native dialects under ideal listening conditions, their ability to recognize words in these dialects may be highly susceptible to the influence of environmental degradation. Fully adult-like word identification for speakers with unfamiliar accents and dialects may exhibit a protracted developmental trajectory.

  5. Quiet Eye Duration Is Responsive to Variability of Practice and to the Axis of Target Changes

    Science.gov (United States)

    Horn, Robert R.; Okumura, Michelle S.; Alexander, Melissa G. F.; Gardin, Fredrick A.; Sylvester, Curtis T.

    2012-01-01

    We tested the hypothesis that quiet eye, the final fixation before the initiation of a movement in aiming tasks, is used to scale the movement's parameters. Two groups of 12 participants (N = 24) threw darts to targets in the horizontal and vertical axes under conditions of higher (random) or lower (blocked) target variability. Supporting our…

  6. "Quiet Food Sovereignty” as Food Sovereignty without Movements? Understanding Food Sovereignty in Post-Socialist Russia

    NARCIS (Netherlands)

    O. Visser (Oane); N.V. Mamonova (Natalia); M.N. Spoor (Max); A. Nikulin (Alexander)

    2017-01-01

    textabstractWhat does food sovereignty look like in settings where rural social movements are weak or non-existent, such as in countries with post-socialist, semi-authoritarian regimes? Focusing on Russia, we present a divergent form of food sovereignty. Building on the concept of ‘quiet

  7. First NuSTAR Limits on Quiet Sun Hard X-Ray Transient Events

    DEFF Research Database (Denmark)

    Marsh, Andrew J.; Smith, David M.; Glesener, Lindsay

    2017-01-01

    We present the first results of a search for transient hard X-ray (HXR) emission in the quiet solar corona with the Nuclear Spectroscopic Telescope Array (NuSTAR) satellite. While NuSTAR was designed as an astrophysics mission, it can observe the Sun above 2 keV with unprecedented sensitivity due...... to its pioneering use of focusing optics. NuSTAR first observed quiet-Sun regions on 2014 November 1, although out-of-view active regions contributed a notable amount of background in the form of single-bounce (unfocused) X-rays. We conducted a search for quiet-Sun transient brightenings on timescales...... as model-independent photon fluxes. The limits in both bands are well below previous HXR microflare detections, though not low enough to detect events of equivalent T and EM as quiet-Sun brightenings seen in soft X-ray observations. We expect future observations during solar minimum to increase the Nu...

  8. Design and development of a quiet, self-thrusting blast hole

    CSIR Research Space (South Africa)

    Ottermann, RW

    2001-08-01

    Full Text Available and demonstrated. The primary output of this project is a quiet, ergonomically, reliable blast hole drilling system, which is used to drill suitable blast holes by workers responsible for drilling these holes. The system has to be safe and reliable with reduced...

  9. Brief quiet ego contemplation reduces oxidative stress and mind-wandering

    Directory of Open Access Journals (Sweden)

    Heidi A. Wayment

    2015-09-01

    Full Text Available Excessive self-concern increases perceptions of threat and defensiveness. In contrast, fostering a more inclusive and expanded sense of self can reduce stress and improve well-being. We developed and tested a novel brief intervention designed to strengthen a student’s compassionate self-identity, an identity that values balance and growth by reminding them of four quiet ego characteristics: detached awareness, inclusive identity, perspective taking, and growth. Students (N = 32 in their first semester of college who reported greater self-protective (e.g., defensive goals in the first two weeks of the semester were invited to participate in the study. Volunteers were randomly assigned to one of three conditions: quiet ego contemplation (QEC, QEC with virtual reality headset (QEC-VR, and control. Participants came to the lab three times to engage in a 15-minute exercise in a 30-day period. The 15-minute Quiet Ego Contemplation (QEC briefly described each quiet ego characteristic followed by a few minutes time to reflect on what that characteristic meant to them. Those in the QEC condition reported improved quiet ego characteristics and pluralistic thinking, decreases in a urinary marker of oxidative stress, and reduced mind-wandering on a cognitive task. Contrary to expectation, participants who wore the VR headsets while listening to the QEC demonstrated the least improvement. Results suggest that a brief intervention that reduces self-focus and strengthens a more compassionate self-view may offer an additional resource that individuals can use in their everyday lives.

  10. Phase synchronisation of the three leg joints in quiet human stance.

    Science.gov (United States)

    Günther, Michael; Putsche, Peter; Leistritz, Lutz; Grimmer, Sten

    2011-03-01

    Quiet human stance is a dynamic multi-segment phenomenon. In literature, coupled ankle and hip actions are in the focus and examinations are usually restricted to frequency contributions below 4 Hz. Very few studies point to the knee playing an active role, and just one study gives evidence of higher frequency contributions. In order to investigate the dynamic coupling of all three leg joints in more depth, we revisited an experimental data set on quiet human stance. Since phase synchronisation is a strong indicator of non-linear coupling behind, we used the phase synchronisation index (PSI) to quantify the degree of leg joint coupling as a function of frequency. One main result is that we did not find any synchronisation between ankle and hip across the whole frequency range examined up to 8 Hz. In contrast, there is significant synchronisation between ankle and knee at a couple of frequencies between 1.25 Hz and 8 Hz when looking at the kinematics. Their joint torques rather synchronise below 2 Hz. There is also synchronisation between knee and hip kinematics above 6 Hz, however, only significant at one frequency bin in our data set. From this, we would infer that the multiple mechanical degrees of freedom contributing to quiet human stance should be chosen according to, thus map, physiology. Thereby, the knee is indispensable and bi-articular muscles play a central role in organising quiet human stance. Examining the non-stationarity of phase synchronisations will probably advance the understanding of self-organisation of quiet human stance. Copyright © 2010 Elsevier B.V. All rights reserved.

  11. Role and responsibilities of medical physicists in radiology and membership of Bulgaria in European union

    International Nuclear Information System (INIS)

    Todorov, V.; Vassileva, J.

    2006-01-01

    Full text: Medical radiology and especially the radiotherapy is the birthplace of modern medical physics. Medical physicists have proven place and important role in research and practice in radiotherapy. They share the responsibility with physicians in varied daily work in this medical speciality. The rapid development of medical imaging in last decades increases the need of competence of medical physicists. Quality assurance in Diagnostic Radiology aimed to achieve maximum diagnostic information at minimal risk and with minimal prize, which is obligatory for the members of the EU, is impossible to be implemented without medical physicists. The enforced recently Ordinance 30/2005 of the Ministry of Health forms the regulatory basis of obligatory implementation of Quality Assurance at medical use of ionizing radiation in the country. This Ordinance introduces the requirements of the EURATOM 97/43 Directive on health protection of individuals against the dangers of ionizing radiation in relation to medical exposure. It regulates also the responsibilities of medical physicists in radiology. Forthcoming is the practical implementation of these requirements, which needs the competence and efforts of Medical physics community as well as of radiologists in the country

  12. South African Association of Physicists in Medicine and Biology: 26. annual congress

    International Nuclear Information System (INIS)

    1986-01-01

    The twenty-sixth annual congress of the South African Association of Physicists in Medicine and Biology was held from 18-21 March 1986 in Pretoria. Papers delivered on the conference covered subjects like medical physics, radiotherapy, radiation protection, calibration of radiation monitors, radiation detectors, radiation doses and dosimetry

  13. Half Life: The Divided Life of Bruno Pontecorvo, Physicist or Spy

    International Nuclear Information System (INIS)

    Close, Frank

    2016-01-01

    It was at the height of the Cold War, in the summer of 1950, when Bruno Pontecorvo mysteriously vanished behind the Iron Curtain. Who was he, and what caused him to disappear? Was he simply a physicist, or also a spy and communist radical? A protege of Enrico Fermi, Pontecorvo was one of the most promising nuclear physicists in the world. He spent years hunting for the Higgs boson of his day - the neutrino - a nearly massless particle thought to be essential to the process of particle decay. His work on the Manhattan Project helped to usher in the nuclear age, and confirmed his reputation as a brilliant physicist. Why, then, would he disappear as he stood on the cusp of true greatness, perhaps even the Nobel Prize? In this book, physicist and historian Frank Close offers a heretofore untold history of Pontecorvo's life, based on unprecedented access to Pontecorvo's friends and family and the Russian scientists with whom he would later work. Close takes a microscope to Pontecorvo's life, combining a thorough biography of one of the most important scientists of the twentieth century with the drama of Cold War espionage. With all the elements of a Cold War thriller - classified atomic research, an infamous double agent, a possible kidnapping by Soviet operatives - this book is a history of nuclear physics at perhaps its most powerful: when it created the bomb

  14. INDEFINITE CONTRACT REVIEW 1999 Procedure for Research Physicists (Professional Category 1)

    CERN Multimedia

    1999-01-01

    In view of the long-standing deliberate turnover policy of professional category 1 research physicists on fixed-term contracts, a special procedure is defined, distinct from the other professional categories. This procedure takes into account that research physicists stay at CERN for only up to 6 years and that periods of service as Fellow may be counted within these six years.The following procedure has been agreed:1.\tThe review covers research physicists holding fixed-term contracts and having completed at least 4 years of service on 30 June 1999. Prior years as Fellow may be taken into consideration in the specific context.\tAll candidates are informed individually.2.\tThe files of all candidates are considered by search committees. The members of the committees are nominated by the Director-General and comprise members of the senior CERN staff as well as at least one senior external physicist. The committees are free to take up references and to interview the candidates.3.\tIn ord...

  15. Internal qualification and credentialing of radiation oncology physicists to perform patient special procedures

    Directory of Open Access Journals (Sweden)

    Michael D Mills

    2014-01-01

    Full Text Available In the arena of radiation oncology special procedures, medical physicists are often the focus professionals for implementation and administration of advanced and complex technologies. One of the most vexing and challenging aspects of managing complexity concerns the ongoing internal qualification and credentialing of radiation oncology physicists to perform patient special procedures. To demonstrate ongoing qualification, a physicist must a document initial training and successful completion of competencies to implement and perform this procedure, b demonstrate familiarity with all aspects of the commissioning and quality assurance process, c demonstrate continuing education respecting this procedure, d demonstrate the peer-reviewed completion of a minimum number of patient special procedures during a specified time span, and e demonstrate satisfactory overall progress toward maintenance of specialty board certification. In many respects, this information complement is similar to that required by an accredited residency program in therapy physics. In this investigation, we report on the design of a management tool to qualify staff radiation oncology physicists to deliver patient procedures.

  16. Brookhaven Lab physicist William Willis wins the 2003 W.K.H. Panofsky prize

    CERN Multimedia

    2003-01-01

    William Willis, a senior physicist Brookhaven National Laboratory, has won the American Physical Society's 2003 W.K.H. Panofsky Prize in Experimental Particle Physics. He received the prize, which consists of $5,000 and a certificate citing his contributions to physics, at the APS meeting in Philadelphia on April 6 (1 page).

  17. 14. Meeting of the North and Northeast physicists. Program and abstracts

    International Nuclear Information System (INIS)

    1996-01-01

    These proceedings contain abstracts of oral and panel presentations carried out during the 14 Meeting of physicists of North and Northeast held in Aracaju, State of Sergipe, Brazil. While covering different areas of physics, they emphasized the condensed matter, statistical physics and nuclear physics in their theoretical and experimental aspects

  18. Clinical Training of Medical Physicists Specializing in Radiation Oncology (French Ed.)

    International Nuclear Information System (INIS)

    2012-01-01

    The application of radiation in human health, for both diagnosis and treatment of disease, is an important component of the work of the IAEA. The responsibility for the increasing technical aspects of this work is undertaken by the medical physicist. To ensure good practice in this vital area structured clinical training programmes are required to complement academic learning. This publication is intended to be a guide to the practical implementation of such a programme for radiation therapy. There is a general and growing awareness that radiation medicine is increasingly dependant on well trained medical physicists that are based in the clinical setting. However an analysis of the availability of medical physicists indicates a large shortfall of qualified and capable professionals. This is particularly evident in developing countries. While strategies to increase academic educational opportunities are critical to such countries, the need for guidance on structured clinical training was recognised by the members of the Regional Cooperative Agreement (RCA) for research, development and training related to nuclear sciences for Asia and the Pacific. Consequently a technical cooperation regional project (RAS6038) under the RCA programme was formulated to address this need in the Asia Pacific region by developing suitable material and establishing its viability. Development of a clinical training guide for medical physicists specialising in radiation therapy was started in 2005 with the appointment of a core drafting committee of regional and international experts. Since 2005 the IAEA has convened two additional consultant group meetings including additional experts to prepare the present publication. The publication drew heavily, particularly in the initial stages, from the experience and documents of the Clinical Training Programme for Radiation Oncology Medical Physicists as developed by the Australasian College of Physical Scientists and Engineers in Medicine. Their

  19. Dad's in the Garage: Santa Barbara Physicists in the Long 1970s

    Science.gov (United States)

    Mody, Cyrus

    2013-03-01

    American physicists faced many challenges in the 1970s: declining research budgets; public skepticism of scientific authority; declining student enrollments; and pressure to shift to topics such as biomedicine, environmental remediation, alternative energy, public housing and transport, and disability technologies. This paper examines the responses to these challenges of a small group of Santa Barbara physicists. While this group is not representative of the American physics profession, the success and failure of their responses to changed conditions tells us something about how American physicists got through the 1970s, and about the origins of some features of American physics today. The three physicists examined here are Philip Wyatt, David Phillips, and Virgil Elings. In the late `60s, Wyatt left a defense think tank to found an instrumentation firm. The Santa Barbara oil spill and other factors pushed that firm toward civilian markets in biomedicine and pollution measurement. Phillips joined Wyatt's firm from UCSB, while also founding his own company, largely to sell electronic devices for parapsychology. Phillips was also the junior partner in a master's of scientific instrumentation degree curriculum founded by Elings in order to save UCSB Physics' graduate program. Through the MSI program, Elings moved into biomedical research and became a serial entrepreneur. By the 1990s, Wyatt, Phillips, and Elings' turn toward academic entrepreneurship, dual military-civilian markets for physics start-ups, and interdisciplinary collaborations between physicists and life scientists were no longer unusual. Together, their journey through the `70s shows how varied the physics' profession's response to crisis was, and how much it pivoted on new interactions between university and industry.

  20. Clinical Training of Medical Physicists Specializing in Radiation Oncology (Spanish Ed.)

    International Nuclear Information System (INIS)

    2012-01-01

    The application of radiation in human health, for both diagnosis and treatment of disease, is an important component of the work of the IAEA. The responsibility for the increasing technical aspects of this work is undertaken by the medical physicist. To ensure good practice in this vital area structured clinical training programmes are required to complement academic learning. This publication is intended to be a guide to the practical implementation of such a programme for radiation therapy. There is a general and growing awareness that radiation medicine is increasingly dependant on well trained medical physicists that are based in the clinical setting. However an analysis of the availability of medical physicists indicates a large shortfall of qualified and capable professionals. This is particularly evident in developing countries. While strategies to increase academic educational opportunities are critical to such countries, the need for guidance on structured clinical training was recognised by the members of the Regional Cooperative Agreement (RCA) for research, development and training related to nuclear sciences for Asia and the Pacific. Consequently a technical cooperation regional project (RAS6038) under the RCA programme was formulated to address this need in the Asia Pacific region by developing suitable material and establishing its viability. Development of a clinical training guide for medical physicists specialising in radiation therapy was started in 2005 with the appointment of a core drafting committee of regional and international experts. Since 2005 the IAEA has convened two additional consultant group meetings including additional experts to prepare the present publication. The publication drew heavily, particularly in the initial stages, from the experience and documents of the Clinical Training Programme for Radiation Oncology Medical Physicists as developed by the Australasian College of Physical Scientists and Engineers in Medicine. Their

  1. Exploratory X-ray Monitoring of z>4 Radio-Quiet Quasars

    Science.gov (United States)

    Shemmer, Ohad

    2017-09-01

    We propose to extend our exploratory X-ray monitoring project of some of the most distant radio-quiet quasars by obtaining one snapshot observation per Cycle for each of four sources at z>4. Combining these observations with six available X-ray epochs per source will provide basic temporal information over rest-frame timescales of 3-5 yr. We are supporting this project with Swift monitoring of luminous radio-quiet quasars at z=1.3-2.7 to break the L-z degeneracy and test evolutionary scenarios of the central engine in active galactic nuclei. Our ultimate goal is to provide a basic assessment of the X-ray variability properties of luminous quasars at the highest accessible redshifts that will serve as the benchmark for X-ray variability studies of such sources with future X-ray missions.

  2. DIFFERENCES BETWEEN RADIO-LOUD AND RADIO-QUIET γ -RAY PULSARS AS REVEALED BY FERMI

    Energy Technology Data Exchange (ETDEWEB)

    Hui, C. Y.; Lee, Jongsu [Department of Astronomy and Space Science, Chungnam National University, Daejeon (Korea, Republic of); Takata, J. [Institute of Particle physics and Astronomy, Huazhong University of Science and Technology (China); Ng, C. W.; Cheng, K. S., E-mail: cyhui@cnu.ac.kr, E-mail: takata@hust.edu.cn [Department of Physics, University of Hong Kong, Pokfulam Road (Hong Kong)

    2017-01-10

    By comparing the properties of non-recycled radio-loud γ -ray pulsars and radio-quiet γ -ray pulsars, we have searched for the differences between these two populations. We found that the γ -ray spectral curvature of radio-quiet pulsars can be larger than that of radio-loud pulsars. Based on the full sample of non-recycled γ -ray pulsars, their distributions of the magnetic field strength at the light cylinder are also found to be different. We note that this might result from an observational bias. By reexamining the previously reported difference of γ -ray-to-X-ray flux ratios, we found that the significance can be hampered by their statistical uncertainties. In the context of the outer gap model, we discuss the expected properties of these two populations and compare with the possible differences that are identified in our analysis.

  3. [Descending control of quiet standing and walking: a plausible neurophysiological basis of falls in elderly people].

    Science.gov (United States)

    Nakajima, Masashi

    2011-03-01

    Quiet standing and walking are generally considered to be an automatic process regulated by sensory feedback. In our report "Astasia without abasia due to peripheral neuropathy," which was published in 1994, we proposed that forced stepping in patients lacking the ankle torque is a compensatory motor control in order to maintain an upright posture. A statistical-biomechanics approach to the human postural control system has revealed open-loop (descending) control as well as closed-loop (feedback) control in quiet standing, and fractal dynamics in stride-to-stride fluctuations of walking. The descending control system of bipedal upright posture and gait may have a functional link to cognitive domains. Increasing dependence on the descending control system with aging may play a role in falls in elderly people.

  4. STUDY OF CALIBRATION OF SOLAR RADIO SPECTROMETERS AND THE QUIET-SUN RADIO EMISSION

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Chengming; Yan, Yihua; Tan, Baolin; Fu, Qijun; Liu, Yuying [Key Laboratory of Solar Activity, National Astronomical Observatories of Chinese Academy of Sciences, Datun Road A20, Chaoyang District, Beijing 100012 (China); Xu, Guirong [Hubei Key Laboratory for Heavy Rain Monitoring and Warning Research, Institute of Heavy Rain, China Meteorological Administration, Wuhan 430205 (China)

    2015-07-20

    This work presents a systematic investigation of the influence of weather conditions on the calibration errors by using Gaussian fitness, least chi-square linear fitness, and wavelet transform to analyze the calibration coefficients from observations of the Chinese Solar Broadband Radio Spectrometers (at frequency bands of 1.0–2.0 GHz, 2.6–3.8 GHz, and 5.2–7.6 GHz) during 1997–2007. We found that calibration coefficients are influenced by the local air temperature. Considering the temperature correction, the calibration error will reduce by about 10%–20% at 2800 MHz. Based on the above investigation and the calibration corrections, we further study the radio emission of the quiet Sun by using an appropriate hybrid model of the quiet-Sun atmosphere. The results indicate that the numerical flux of the hybrid model is much closer to the observation flux than that of other ones.

  5. Models of the quiet and active solar atmosphere from Harvard OSO data.

    Science.gov (United States)

    Noyes, R. W.

    1971-01-01

    Review of some Harvard Observatory programs aimed at defining the physical conditions in quiet and active solar regions on the basis of data obtained from the OSO-IV and OSO-VI spacecraft. The spectral range covered is from 300 A to 1400 A. This spectral range consists of emission lines and continua from abundant elements such as hydrogen, helium, carbon, nitrogen, oxygen, silicon, magnesium, aluminum, neon, iron, and calcium in various ionization states ranging from neutral to 15 times ionized. The structure is discussed of the quiet solar atmosphere as deduced from center-to-limb behavior of spectral lines and continua formed in the chromosphere and corona. In reviewing investigations of solar active regions, it is shown that the structure of these regions varies in a complicated manner from point to point. The local structure is influenced by factors such as the magnetic field configuration within the active region and the age or evolutionary state of the region.

  6. X-RAY PULSATIONS FROM THE RADIO-QUIET GAMMA-RAY PULSAR IN CTA 1

    International Nuclear Information System (INIS)

    Caraveo, P. A.; De Luca, A.; Marelli, M.; Bignami, G. F.; Ray, P. S.; Saz Parkinson, P. M.; Kanbach, G.

    2010-01-01

    Prompted by the Fermi-LAT discovery of a radio-quiet gamma-ray pulsar inside the CTA 1 supernova remnant, we obtained a 130 ks XMM-Newton observation to assess the timing behavior of this pulsar. Exploiting both the unprecedented photon harvest and the contemporary Fermi-LAT timing measurements, a 4.7σ single-peak pulsation is detected, making PSR J0007+7303 the second example, after Geminga, of a radio-quiet gamma-ray pulsar also seen to pulsate in X-rays. Phase-resolved spectroscopy shows that the off-pulse portion of the light curve is dominated by a power-law, non-thermal spectrum, while the X-ray peak emission appears to be mainly of thermal origin, probably from a polar cap heated by magnetospheric return currents, pointing to a hot spot varying throughout the pulsar rotation.

  7. The dynamic quiet solar corona: 4 days of joint observing with MDI and EIT

    Science.gov (United States)

    Schrijver, C. J.; Shine, R. A.; Hurlburt, N. E.; Tarbell, T. D.; Lemen, J. R.

    1997-01-01

    The analysis of a sequence of joint extreme ultraviolet imaging telescope (EIT) Fe XII and Michelson Doppler imager (MDI) magnetogram observations of the quiet sun near disk center is presented. It was found that: all the emerging flux above the threshold of approximately 10(sup 17) Mx is associated with enhanced coronal emissions; loop systems between the polarities in ephemeral regions remain visible up to separations of 10000 up to 30000 km; brightenings between approaching opposite polarity network concentrations form when the concentrations are between 5000 and 25000 km apart, and that faint connections up to 40000 km in length form as sets of concentrations of the same polarity coagulate. The coronal emission over patches of the quiet sun depends on the total flux in connected concentrations, on their distance and on the positions and strengths of neighboring concentrations.

  8. Review: Donald Seekins: Burma and Japan since 1940. From ‘Co-Prosperity’ to ‘Quiet Dialogue’ (2008 Buchbesprechung: Donald Seekins: Burma and Japan since 1940. From ‘Co-Prosperity’ to ‘Quiet Dialogue’ (2008

    Directory of Open Access Journals (Sweden)

    Hans-Bernd Zöllner

    2009-04-01

    Full Text Available Review of the monograph: Donald Seekins: Burma and Japan since 1940. From ‘Co-Prosperity’ to ‘Quiet Dialogue’ Copenhagen: NIAS Press, 2008, ISBN 978 87 7694 017 1, 191 pages Besprechung der Monographie: Donald Seekins: Burma and Japan since 1940. From ‘Co-Prosperity’ to ‘Quiet Dialogue’ Kopenhagen: NIAS Press, 2008, ISBN 978 87 7694 017 1, 191 Seiten

  9. Diurnal and Seasonal Variations in Mid-Latitude Geomagnetic Field During International Quiet Days: BOH Magnetometer

    Directory of Open Access Journals (Sweden)

    Junga Hwang

    2012-12-01

    Full Text Available Korea Astronomy and Space Science Institute researchers have installed and operated magnetometers at Bohyunsan Observatory to measure the Earth's magnetic field variations in South Korea. In 2007, we installed a fluxgate magnetometer (RFP-523C to measure H, D, and Z components of the geomagnetic field. In addition, in 2009, we installed a Overhauser proton sensor to measure the absolute total magnetic field F and a three-axis magneto-impedance sensor for spectrum analysis. Currently three types of magnetometer data have been accumulated. In this paper, we use the H, D, Z components of fluxgate magnetometer data to investigate the characteristics of mid-latitude geomagnetic field variation. To remove the temporary changes in Earth’s geomagnetic filed by space weather, we use the international quiet days’ data only. In other words, we performed a superposed epoch analysis using five days per each month during 2008-2011. We find that daily variations of H, D, and Z shows similar tendency compared to previous results using all days. That is, H, D, Z all three components’ quiet intervals terminate near the sunrise and shows maximum 2-3 hours after the culmination and the quiet interval start from near the sunset. Seasonal variations show similar dependences to the Sun. As it becomes hot season, the geomagnetic field variation’s amplitude becomes large and the quiet interval becomes shortened. It is well-known that these variations are effects of Sq current system in the Earth’s atmosphere. We confirm that the typical mid-latitude geomagnetic field variations due to the Sq current system by excluding all possible association with the space weather.

  10. On abnormal quiet day Sq(Z) ranges in the Indian region

    International Nuclear Information System (INIS)

    Thakur, N.K.; Sontakke, K.G.

    1981-01-01

    Solar quiet day variations of the vertical geomagnetic component Sq(Z) have been studied. These show abnormal variations from day to day. The study for the period 1961 to 1976 indicates that, for quite a number of days, the Sq(Z) phase reverses completely. It is concluded that changes in phase of Sq(Z) could be explained by the movement of the Sq current system and the penetration of the Sq southern current system into the northern hemisphere. (author)

  11. Modelling the quiet-time geomagnetic daily variations using observatory data

    OpenAIRE

    Hamilton, Brian; Macmillan, Susan

    2008-01-01

    We present on-going work towards building a global model of the quiet-time geomagnetic daily variation using bservatory data. We select hourly mean data during June 2006 (solar minimum). We fit Fourier series in time, with a fundamental period of 24 hours, to the data at each observatory. We then use global spherical harmonic expansions to separate the daily variation signal, as characterised by the Fourier coefficients in time, into external and induced internal contributions. The mode...

  12. Solar quiet day ionospheric source current in the West African region

    OpenAIRE

    Obiekezie, Theresa N.; Okeke, Francisca N.

    2012-01-01

    The Solar Quiet (Sq) day source current were calculated using the magnetic data obtained from a chain of 10 magnetotelluric stations installed in the African sector during the French participation in the International Equatorial Electrojet Year (IEEY) experiment in Africa. The components of geomagnetic field recorded at the stations from January–December in 1993 during the experiment were separated into the source and (induced) components of Sq using Spherical Harmonics Analysis (SHA) method....

  13. MULTIWAVELENGTH OBSERVATIONS OF RADIO-QUIET QUASARS WITH WEAK EMISSION LINES

    International Nuclear Information System (INIS)

    Plotkin, Richard M.; Anderson, Scott F.; MacLeod, Chelsea L.; Brandt, W. N.; Schneider, Donald P.; Diamond-Stanic, Aleksandar M.; Fan Xiaohui; Shemmer, Ohad

    2010-01-01

    We present radio and X-ray observations, as well as optical light curves, for a subset of 26 BL Lac candidates from the Sloan Digital Sky Survey (SDSS) lacking strong radio emission and with z < 2.2. Half of these 26 objects are shown to be stars, galaxies, or absorbed quasars. We conclude that the other 13 objects are active galactic nuclei (AGNs) with abnormally weak emission features; 10 of those 13 are definitively radio quiet, and, for those with available optical light curves, their level of optical flux variability is consistent with radio-quiet quasars. We cannot exclude the possibility that some of these 13 AGNs lie on the extremely radio-faint tail of the BL Lac distribution, but our study generally supports the notion that all BL Lac objects are radio-loud. These radio-quiet AGNs appear to have intrinsically weak or absent broad emission line regions (BELRs), and, based on their X-ray properties, we argue that some are low-redshift analogs to weak line quasars (WLQs). SDSS BL Lac searches are so far the only systematic surveys of the SDSS database capable of recovering such exotic low-redshift WLQs. There are 71 more z < 2.2 radio-quiet BL Lac candidates already identified in the SDSS, but not considered here, and many of those might be best unified with WLQs as well. Future studies combining low- and high-redshift WLQ samples will yield new insight on our understanding of the structure and formation of AGN BELRs.

  14. Artificial cooling due to quiet injection in bounded plasma particle simulations

    International Nuclear Information System (INIS)

    Lawson, W.S.

    1988-01-01

    An explanation is proposed for an artificial cooling effect seen in electrostatic particle-in-cell plasma simulations. The effect hinges on heat transport from the trapped electrons to fluctuations of the electric field, which are kept at a sub-thermal level through the continuous ''quiet'' injection of passing electrons. Further simulations are done which test and support the explanation. copyright 1988 Academic Press, Inc

  15. Critical Magnetic Field Strengths for Unipolar Solar Coronal Plumes In Quiet Regions and Coronal Holes?

    Science.gov (United States)

    Avallone, Ellis; Tiwari, Sanjiv K.; Panesar, Navdeep K.; Moore, Ronald L.; Winebarger, Amy

    2017-01-01

    Coronal plumes are bright magnetic funnels that are found in quiet regions and coronal holes that extend high into the solar corona whose lifetimes can last from hours to days. The heating processes that make plumes bright involve the magnetic field at the base of the plume, but their intricacies remain mysterious. Raouafi et al. (2014) infer from observation that plume heating is a consequence of magnetic reconnection at the base, whereas Wang et al. (2016) infer that plume heating is a result of convergence of the magnetic flux at the plume's base, or base flux. Both papers suggest that the base flux in their plumes is of mixed polarity, but do not quantitatively measure the base flux or consider whether a critical magnetic field strength is required for plume production. To investigate the magnetic origins of plume heating, we track plume luminosity in the 171 Å wavelength as well as the abundance and strength of the base flux over the lifetimes of six unipolar coronal plumes. Of these, three are in coronal holes and three are in quiet regions. For this sample, we find that plume heating is triggered when convergence of the base flux surpasses a field strength of approximately 300 - 500 Gauss, and that the luminosity of both quiet region and coronal hole plumes respond similarly to the strength of the magnetic field in the base.

  16. "Quiet flows the Don" by M.A. Sholokhov: evolution of interpretation by Chinese critics

    Directory of Open Access Journals (Sweden)

    Tsytsenko Irina Ivanovna

    2015-12-01

    Full Text Available This article attempts to analyze and give a general idea about the main approaches to the study of “Quiet Flows the Don” in China from 1949 to the 2000s, which is essential for the reconstruction and the description of the international reception of Mikhail Sholokhov’s creativity in general, and also allows to see the dynamics of the perception process of the individual specific cultural dialogue between Russia and China in the XX century, due to the political, historical, aesthetic and linguistic factors. The development of “Quiet Flows the Don” in Chinese literary criticism has two main stages: 1949-1985s (one-sided interpretation of “Quiet Flows the Don” in the context of political culture and the 1985-2000s (a scientific approach in the context of a non-political culture. Each of these stages considers separate periods marking the specifics of the study related to the specific feature of China’s historical and cultural situation, analyzes the most interesting point of view of Chinese researchers. Great attention is given to the issues that were discussed in the Chinese literary criticism and topical issues that reflect the experience of revolution and civil war, the question about the main character of the epic novel and the origins of the tragedy and artistic skill of Sholokhov. Key words: reception, art world, paradigm of socio-cultural factors, ideological and artistic humanism, concept of the character.

  17. Numerical simulations of quiet Sun magnetic fields seeded by the Biermann battery

    Science.gov (United States)

    Khomenko, E.; Vitas, N.; Collados, M.; de Vicente, A.

    2017-08-01

    The magnetic fields of the quiet Sun cover at any time more than 90% of its surface and their magnetic energy budget is crucial to explain the thermal structure of the solar atmosphere. One of the possible origins of these fields is the action of the local dynamo in the upper convection zone of the Sun. Existing simulations of the local solar dynamo require an initial seed field and sufficiently high spatial resolution in order to achieve the amplification of the seed field to the observed values in the quiet Sun. Here we report an alternative model of seeding based on the action of the Bierman battery effect. This effect generates a magnetic field due to the local imbalances in electron pressure in the partially ionized solar plasma. We show that the battery effect self-consistently creates from zero an initial seed field of a strength of the order of micro G, and together with dynamo amplification allows the generation of quiet Sun magnetic fields of a similar strength to those from solar observations.

  18. Quiet ionospheric currents of the southern hemisphere derived from geomagnetic records

    International Nuclear Information System (INIS)

    Campbell, W.H.; Schiffmacher, E.R.

    1988-01-01

    This work describes the month-by-month behavior of the equivalent ionospheric current systems derived from spherical harmonic analyses of the quiet time geomagnetic field daily variations in 1965 at selected observatories representing the three southern global half-sector regions separately encompassing South America, Africa, and Australia. These external Sq current patterns were vortices having mid-latitude foci with midday summertime amplitudes reaching 16.2 x 10 4 A above the midnight level. The wintertime amplitudes were about 10 x 10 4 A smaller. At low latitudes there was a large intrusion of the opposite hemisphere external Sq current system into the wintertime hemisphere at prenoon hours, displacing the primary current vortex to later postnoon hours. The behavior of the southern hemisphere external currents were found to be seasonally similar to those of the northern hemisphere for the same year. The quiet year behavior was compared to the results for the 1958 active year determined earlier by Matsushita. The winter-to-summertime increase in focus current was found to be similar in amplitude for the 2 years. The active year summertime and equinoctial current focus amplitudes were about 2.3 times the amplitudes of corresponding months in the quiet year

  19. The effects of vision-related aspects on noise perception of wind turbines in quiet areas.

    Science.gov (United States)

    Maffei, Luigi; Iachini, Tina; Masullo, Massimiliano; Aletta, Francesco; Sorrentino, Francesco; Senese, Vincenzo Paolo; Ruotolo, Francesco

    2013-04-26

    Preserving the soundscape and geographic extension of quiet areas is a great challenge against the wide-spreading of environmental noise. The E.U. Environmental Noise Directive underlines the need to preserve quiet areas as a new aim for the management of noise in European countries. At the same time, due to their low population density, rural areas characterized by suitable wind are considered appropriate locations for installing wind farms. However, despite the fact that wind farms are represented as environmentally friendly projects, these plants are often viewed as visual and audible intruders, that spoil the landscape and generate noise. Even though the correlations are still unclear, it is obvious that visual impacts of wind farms could increase due to their size and coherence with respect to the rural/quiet environment. In this paper, by using the Immersive Virtual Reality technique, some visual and acoustical aspects of the impact of a wind farm on a sample of subjects were assessed and analyzed. The subjects were immersed in a virtual scenario that represented a situation of a typical rural outdoor scenario that they experienced at different distances from the wind turbines. The influence of the number and the colour of wind turbines on global, visual and auditory judgment were investigated. The main results showed that, regarding the number of wind turbines, the visual component has a weak effect on individual reactions, while the colour influences both visual and auditory individual reactions, although in a different way.

  20. Brightness temperature of the ''quiet'' Sun in the millimeter wavelength range

    International Nuclear Information System (INIS)

    Pelyushenko, S.A.

    1982-01-01

    Results are presented of recalibration of the data available for measurements of the solar brightness temperature Tsub(s) made by comparison with the lunar radio emission. A spectrum has been obtained of the ''quiet'' Sun radio emission in the range of 1-20 mm. The mean square spread of data does not exceed +-(from 3 to 4)%. The ''quiet'' Sun spectrum has a form of: Tsub(c)=(6150+-70)lambdasup(01+-0.01)[mm]K in the wavelength interval of lambda=(1-6) mm and Tsub(c)=(3470+-80)lambdasup(0.42+-0.01) [mm]K in the wavelength interval of lambda=(7-20) mm on approximation of recalibrated values of Tsub(c) with a linear dependence using the mean-square-root method. The obtained spectral characteristics of the ''quiet'' Sun radio frequency emission in the mullimeter wavelength range testify on the spectrum flatteming in the (1-6) mm wavelength range

  1. Horse-collar aurora: A frequent pattern of the aurora in quiet times

    International Nuclear Information System (INIS)

    Hones, E.W. Jr.; Craven, J.D.; Frank, L.A.; Evans, D.S.; Newell, P.T.

    1989-01-01

    Reported here are DE 1 auroral imager observations of an auroral configuration which is given the name ''horse-collar aurora.'' The horse-collar pattern comprises the total area of auroral emissions from a single hemisphere and derives its name from the shape of the emitting area. The pattern is found in images recorded during quiet geomagnetic conditions and is possibly related to the theta aurora, another quiet time configuration of the auroras. This initial report of the DE 1 observations illustrates the horse-collar aurora with a 2-hour images sequence that displays its basic features and shows an example of its evolution into a theta-like auroral pattern. The interplanetary magnetic field was northward during this image sequence and there is some evidence for IMF B/sub y/ influence of the temporal development of the horse-collar pattern. A preliminary statistical analysis found the horse-collar pattern appearing in one-third or more of image sequences recorded during quiet conditions; it did not appear during disturbed conditions. Further study is required to establish more fully the characteristics of the horse-collar aurora and to determine its implications concerning solar wind-magnetosphere coupling when the IMF B/sub z/ is northward. copyright American Geophysical Union 1989

  2. Thermospheric/ionospheric disturbances under quiet and magneto-perturbed conditions

    Science.gov (United States)

    Zakharov, Ivan G.; Mozgovaya, O. L.

    2003-04-01

    The basic mechanisms of ionospheric storms (IS) are investigated sufficiently full. Despite of it a quantitative forecast of ionospheric disturbance is not always satisfactory. One of the possible causes can be related to the insufficient account of a background ionospheric. In particualr using electron concentration Ne in the peak of F2-region and total electron content are shown, that the amplitude of a IS positive phase for similar magnetic storms can differ by ~1,5 times. Hence a cause of distinction can be variations in the thermosphere conditions, not reflected by known activity indices. For further research we used the incoherent scatter radar data of the Institute of ionosphere in height range 200-1000 km in the very quiet periods coming to the geomagnetic disturbance. A steady periodic disturbance in Ne during quiet conditions in all heights is established, which can be identified as tidal moda m=6. The amplitude of wave is ~15%, the phase changes with a height. The storm onset leads to an increase of the amplitudes approximately twice without a change in the phase. An ionospheric disturbance in very quiet conditions can lead to additional complicating an ionosphere reaction to magnetic storm.

  3. An environmental index of noise and light pollution at EU by spatial correlation of quiet and unlit areas.

    Science.gov (United States)

    Votsi, Nefta-Eleftheria P; Kallimanis, Athanasios S; Pantis, Ioannis D

    2017-02-01

    Quietness exists in places without human induced noise sources and could offer multiple benefits to citizens. Unlit areas are sites free of human intense interference at night time. The aim of this research is to develop an integrated environmental index of noise and light pollution. In order to achieve this goal the spatial pattern of quietness and darkness of Europe was identified, as well as their overlap. The environmental index revealed that the spatial patterns of Quiet and Unlit Areas differ to a great extent highlighting the importance of preserving quietness as well as darkness in EU. The spatial overlap of these two environmental characteristics covers 32.06% of EU surface area, which could be considered a feasible threshold for protection. This diurnal and nocturnal metric of environmental quality accompanied with all direct and indirect benefits to human well-being could indicate a target for environmental protection in the EU policy and practices. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. A half-life the divided life of Bruno Pontecorvo, physicist or spy

    CERN Document Server

    Close, Frank

    2015-01-01

    Bruno Pontecorvo dedicated his career to hunting for the Higgs boson of his day: the neutrino, a nearly massless particle considered essential to the process of nuclear fission. His work on the Manhattan project under Enrico Fermi confirmed his reputation as a brilliant physicist and helped usher in the nuclear age. He should have won a Nobel Prize, but late in the summer of 1950 he vanished. At the height of the Cold War, Pontecorvo had disappeared behind the Iron Curtain. In Half-Life, physicist and historian Frank Close offers a heretofore untold history of Pontecorvo’s life, based on unprecedented access to his friends, family, and colleagues. With all the elements of a Cold War thriller—classified atomic research, an infamous double agent, a kidnapping by Soviet operatives—Half-Life is a history of particle physics at perhaps its most powerful: when it created the bomb.

  5. Fermi: a physicist in the upheaval; Fermi: un physicien dans la tourmente

    Energy Technology Data Exchange (ETDEWEB)

    Maria, M. de

    2002-07-01

    This book summarizes the life, works and complex personality of the Italian physicist Enrico Fermi (1901-1954) whose myth is linked with the political upheaval of the 2. world war: the youth of an autodidact, the theorician and the quantum mechanics, his invention of a quantum statistics, the weak interaction theory, his works on artificial radioactivity, the end of the Fermi team and his exile in the USA, the secrete researches at the university of Columbia and the birth of the first atomic 'pile' (December 2, 1942), the building of Los Alamos center and the Alamogordo explosion test, the disagreements among the physicists of the Manhattan project and the position of Fermi, Fermi's contribution in the H-bomb construction, the creation of the physics school of Chicago, the Oppenheimer spying affair. (J.S.)

  6. Role of the medical physicist in quality control in diagnostic x-ray departments

    International Nuclear Information System (INIS)

    Cameron, J.R.

    1973-01-01

    Medical physicists can play a role in education of future radiologists and technologists by teaching quality control needs and techniques. He or she can also provide service to the diagnostic section by establishing a quality control program. Finally, the medical physicist can play an important role in the development of simple and inexpensive techniques for quality control by radiological technologists. The ongoing work at the University of Wisconsin in this area is to provide quality control in measurement of the effective kVcp, the measurement of the effective focal spot size, the performance of the processing equipment, the output in mR/mAs, and the measurement of the half-value-layer and the total filtration. (U.S.)

  7. Compendium to radiation physics for medical physicists 300 problems and solutions

    CERN Document Server

    Podgorsak, Ervin B

    2014-01-01

    This exercise book contains 300 typical problems and exercises in modern physics and radiation physics with complete solutions, detailed equations and graphs. This textbook is linked directly with the textbook "Radiation Physics for Medical Physicists", Springer (2010) but can also be used in combination with other related textbooks. For ease of use, this textbook has exactly the same organizational layout (14 chapters, 128 sections) as the "Radiation Physics for Medical Physicists" textbook and each section is covered by at least one problem with solution given. Equations, figures and tables are cross-referenced between the two books. It is the only large compilation of textbook material and associated solved problems in medical physics, radiation physics, and biophysics.

  8. General programs of specialized education of radiological physicists in the Czech Republic

    International Nuclear Information System (INIS)

    Dvorak, P.; Judas, L.; Richter, V.; Novak, L.

    2005-01-01

    Specialized Education of Czech radiological physicists in diagnostic radiology (DR), nuclear medicine (NM) or radiotherapy (RT) follows-up to regulated university master program. A form and content of Specialized Education which will be defined by General Programs must therefore reflect previous step. Graduates from Specialized Education will be fully competent clinical radiological physicists for DR, NM or RT according to their branch. Therefore, we strongly recommend that General Programs are made very carefully reflecting requirements of Specialized Education and current status of the field in the Czech Republic. Currently, CAMP works on its own version of General Program for each branch. CAMP is ready to collaborate closely with all other bodies included in preparation of General Programs and with the Czech Ministry of Health. (authors)

  9. Women physicists in Russia: Problems and solutions at a time of fiscal crisis

    Science.gov (United States)

    Didenko, Nelli; Ermolaeva, Elena; Kunitsyna, Ekaterina; Kratasyuk, Valentina; Vitman, Renata

    2013-03-01

    Recently Russia has been affected by the global financial crisis, which has had both positive and negative effects on women physicists. The feminization of science and the stratification that characterize the Russian scientific community in general also affect the field of physics. This paper discusses the proportion of women in leadership and managerial positions in different areas of science and education and highlights the differences between women and men in their careers in physics and defense of their theses. Lomonosov Moscow State University is used to demonstrate the dynamics of gender in different academic positions. The professional activity of young women physicists is illustrated by their participation in all-Russian scientific forums, demonstrating their commitment to remain active in their careers despite the challenges of the current economic conditions.

  10. The radioactivity, the sun, the Earth and Kelvin's death. A difficult dialog between physicists and geologists

    International Nuclear Information System (INIS)

    Richet, P.

    1996-01-01

    The question of the age of the Earth has remained mythical for a long time. During the last quarter of the 19. century, this question was the center of a strong controversy initiated by a physicist, William Thomson, the future Lord Kelvin. During the beginning of the 20. century, the discoveries of Becquerel and Pierre and Marie Curie about radioactivity gave rise to a new generation of physicists who were able to propose radiometric estimations of the Earth's age to geologists. This digest paper describes the historical aspects of the discovery of radioactivity and of the first attempts for dating the Earth using radiometric techniques, and the strong discussions within the geologists community. (J.S.)

  11. The role of medical physicist in health care and radiation protection

    International Nuclear Information System (INIS)

    Mattsson, S.; Adliene, D.

    2004-01-01

    Medical physics is a part of physics that is associated with the practice of medicine dealing with a use of various types of ionizing and non-ionizing radiation for medical purposes as well as with the radiation protection of patients and personnel. The role, responsibilities and duties of medical physicists in the fields of radiation therapy, diagnostic imaging using X-rays and magnetic resonance methods, diagnostics and therapeutic nuclear medicine, radiation dosimetry and radiation protection are discussed in this paper. It is shown that, the medical physicists have the unique possibility to combine their knowledge in medical radiation physics with the recent achievements in medicine and technology and to apply this knowledge for the adequately safe treatment or diagnosis of patients during radiological procedures. (author)

  12. The role of the biomedical physicist in the education of the healthcare professions: an EFOMP project.

    Science.gov (United States)

    Caruana, C J; Wasilewska-Radwanska, M; Aurengo, A; Dendy, P P; Karenauskaite, V; Malisan, M R; Meijer, J H; Mornstein, V; Rokita, E; Vano, E; Wucherer, M

    2009-09-01

    The role of the biomedical physicist in the education of the healthcare professions has not yet been studied in a systematic manner. This article presents the first results of an EFOMP project aimed at researching and developing this important component of the role of the biomedical physicist. A background to the study expands on the reasons that led to the need for the project. This is followed by an extensive review of the published literature regarding the role. This focuses mainly on the teaching contributions within programmes for physicians, diagnostic radiographers, radiation therapists, and the postgraduate medical specializations of radiology, radiotherapy, interventional radiology and cardiology. Finally a summary list of the specific research objectives that need to be immediately addressed is presented. These are the carrying out of a Europe-wide position audit for the role, the construction of a strategic role development model and the design of a curriculum development model suitable for modern healthcare professional education.

  13. MO-C-BRB-04: Observations of a Nuclear Radiologist on the Value of the Medical Physicist

    International Nuclear Information System (INIS)

    Greenspan, B.

    2016-01-01

    With the profound changes currently occurring in medicine, the role of the medical physicist cannot stagnate, but must evolve to meet the challenges and opportunities that are presented. Medical physicists must understand these changes and establish themselves not only as relevant but as leaders in this new environment. We must increase our presence in clinical settings such as tumor boards, patient rounds, and the development of new diagnosis, imaging, and treatment techniques. By establishing ourselves as competent scientists, we can and must participate in the development of technologies through research, teaching, and clinical implementation. As medical physicists we must define our roles and value to our physician colleagues, patients, referring physicians, and senior administrators. We cannot afford to be viewed solely as quality assurance technologists, but need to move forward in step with medical and practice advances, becoming recognized as having a leadership role in providing quality research, technological development, and quality patient care. In this session, four leaders in medical research and healthcare will discuss their observations on how medical physicists have contributed to advancements in healthcare and opportunities to continue leadership in providing quality medicine through the applications of physics to research, education, and clinical practice. Learning Objectives: Understand the changes in the healthcare environment and how medical physicists can contribute to improving patient care. Learn how medical physicists are currently leading research efforts to improve clinical imaging and diagnosis. Understand the role of medical physicists in developing new technology and leading its translation into clinical care.

  14. MO-C-BRB-04: Observations of a Nuclear Radiologist on the Value of the Medical Physicist

    Energy Technology Data Exchange (ETDEWEB)

    Greenspan, B. [Georgia Regents University (Georgia)

    2016-06-15

    With the profound changes currently occurring in medicine, the role of the medical physicist cannot stagnate, but must evolve to meet the challenges and opportunities that are presented. Medical physicists must understand these changes and establish themselves not only as relevant but as leaders in this new environment. We must increase our presence in clinical settings such as tumor boards, patient rounds, and the development of new diagnosis, imaging, and treatment techniques. By establishing ourselves as competent scientists, we can and must participate in the development of technologies through research, teaching, and clinical implementation. As medical physicists we must define our roles and value to our physician colleagues, patients, referring physicians, and senior administrators. We cannot afford to be viewed solely as quality assurance technologists, but need to move forward in step with medical and practice advances, becoming recognized as having a leadership role in providing quality research, technological development, and quality patient care. In this session, four leaders in medical research and healthcare will discuss their observations on how medical physicists have contributed to advancements in healthcare and opportunities to continue leadership in providing quality medicine through the applications of physics to research, education, and clinical practice. Learning Objectives: Understand the changes in the healthcare environment and how medical physicists can contribute to improving patient care. Learn how medical physicists are currently leading research efforts to improve clinical imaging and diagnosis. Understand the role of medical physicists in developing new technology and leading its translation into clinical care.

  15. Communication and information-seeking behavior of PhD students in physicists and astronomy

    OpenAIRE

    Jamali, Hamid R.

    2006-01-01

    As a part of a wider doctoral research, this paper deals with the communication and information-seeking behavior of research (PhD) students in physics and astronomy. Based on a qualitative case study of PhD students in the Department of Physics and Astronomy at University College London, this study seeks to derive behavioral patterns in information-seeking activities of PhD students. The study aims to investigate the intradisciplinary differences in information-seeking activities of physicist...

  16. Salary Information for Nuclear Engineers and Health Physicists, October 1995; FINAL

    International Nuclear Information System (INIS)

    Oak Ridge Institute for Science and Education

    1995-01-01

    Salary information was collected for October 1995 for personnel working as nuclear engineers and health physicists. The salary information includes personnel at the B.S., M.S., and Ph.D. levels with zero, one, and three years of professional work experience. Information is provided for utilities and non-utilities. Non-utilities include private sector organizations and U.S. Department of Energy contractor-operated facilities. Government agencies, the military, academic organizations, and medical facilities are excluded

  17. Procedure for physicist's scanning in the image processing system of bubble chambers

    International Nuclear Information System (INIS)

    Gritsaenko, I.A.; Petrovykh, L.P.; Petrovykh, Yu.L.; Fenyuk, A.B.

    1984-01-01

    The algorithm of the program of physicist's scanning for data processing from photo images in experiments using bubble chambers is described. The program allows one to perform sorting or selection of specific events for subsequent processing and identification of separate particles by bubble density along the track or by the character of the decay. The fraction of protons separated automatically constituted 97%. The program has been used for processing 50 thousand events at the BEBC chamber

  18. Limited Resources, Limited Opportunities, and the Accumulation of Disadvantage: Evidence from the Global Survey of Physicists

    Science.gov (United States)

    Ivie, Rachel

    2012-03-01

    Using the results of the Global Survey of Physicists, which we conducted in collaboration with the International Union of Pure and Applied Physics Working Group on Women, we document the effect of limited resources and opportunities on women physicists' careers. We find that women respondents are less likely than men to report access to a variety of resources and opportunities that would be helpful in advancing a scientific career. These include access to funding, travel money, lab and office space, equipment, clerical support, and availability of employees or students to help with research. When asked about specific opportunities, women report fewer invited talks and overseas research opportunities. Women who responded are less likely to have been journal editors, acted as bosses or managers, advised graduate students, served on thesis or dissertation committees, and served on committees for grant agencies. We also show the disproportionate effects of children on women physicists' careers. Women who responded are more likely than men to have changed their work situations upon becoming parents. Mothers are more likely than men and women without children to report that their careers have progressed more slowly than colleagues who finished their degrees at the same time. Furthermore, women are more likely than men to report that their careers affected the decisions they made about marriage and children. The results of this survey draw attention to the need to focus on factors other than representation when discussing the situation of women in physics. 15,000 physicists in 130 countries answered this survey, and across all these countries, women have fewer resources and opportunities and are more affected by cultural expectations concerning child care. Cultural expectations about home and family are difficult to change. However, for women to have successful outcomes and advance in physics, they must have equal access to resources and opportunities.

  19. Qualification diploma in radiological and medical physics. Evolution of the initial training of hospital physicists

    International Nuclear Information System (INIS)

    Hammadi, A.

    2009-01-01

    This series of slides presents: - the evolution of the radio-physicists training since its creation (history, 1995-2005 era, 2005-2009 changes); - the qualification diploma in radiological and medical physics (QDRMP - DQPRM in French) in figures (validating services, number of qualified people); - the QDRMP context and goals (strength needs, limited number of candidates); - the means implemented to reach the goals; - the perspectives (increase of students number, continuous training). (J.S.)

  20. Role and responsibilities of medical physicists in radiological protection of patients

    International Nuclear Information System (INIS)

    Niroomand-Rad, A.

    2001-01-01

    The paper provides a brief history of the International Organization for Medical Physics (IOMP), followed by some general comments on the radiological protection of patients. The importance of establishing scientific guidelines and professional standards is emphasized, as is the need to ensure the protection of patients undergoing radiation therapy. The responsibility of qualified medical physicists in the protection of patients in nuclear medicine and in diagnostic and interventional radiology is also discussed. (author)

  1. Entrepreneurship for Physicists; A practical guide to move inventions from university to market

    Science.gov (United States)

    Iannuzzi, Davide

    2017-10-01

    This book offers a concise analysis of the key ingredients that enable physicists to successfully move their idea from university to market, bringing added value to their customers. It dives into a set of theories, models, and tools that play fundamental roles in technology transfer including topics often neglected by other books including trust, communication, and persuasion. It also explains how most of the topics discussed are applicable to careers in a broader sense.

  2. Anniversary Paper: The role of medical physicists in developing stereotactic radiosurgery

    International Nuclear Information System (INIS)

    Benedict, Stanley H.; Bova, Frank J.; Clark, Brenda; Goetsch, Steven J.; Hinson, William H.; Leavitt, Dennis D.; Schlesinger, David J.; Yenice, Kamil M.

    2008-01-01

    This article is a tribute to the pioneering medical physicists over the last 50 years who have participated in the research, development, and commercialization of stereotactic radiosurgery (SRS) and stereotactic radiotherapy utilizing a wide range of technology. The authors have described the evolution of SRS through the eyes of physicists from its beginnings with the Gamma Knife in 1951 to proton and charged particle therapy; modification of commercial linacs to accommodate high precision SRS setups; the multitude of accessories that have enabled fine tuning patients for relocalization, immobilization, and repositioning with submillimeter accuracy; and finally the emerging technology of SBRT. A major theme of the article is the expanding role of the medical physicist from that of advisor to the neurosurgeon to the current role as a primary driver of new technology that has already led to an adaptation of cranial SRS to other sites in the body, including, spine, liver, and lung. SRS continues to be at the forefront of the impetus to provide technological precision for radiation therapy and has demonstrated a host of downstream benefits in improving delivery strategies for conventional therapy as well. While this is not intended to be a comprehensive history, and the authors could not delineate every contribution by all of those working in the pursuit of SRS development, including physicians, engineers, radiobiologists, and the rest of the therapy and dosimetry staff in this important and dynamic radiation therapy modality, it is clear that physicists have had a substantial role in the development of SRS and theyincreasingly play a leading role in furthering SRS technology

  3. UC Riverside physicists contribute to state-of-the-art detector installed in Switzerland

    CERN Multimedia

    2008-01-01

    PMUC Riverside scientists led by Gail Hanson, a distinguished professor of physics, are part of a collaboration of approximately 2300 international physicists who announced Dec. 19 that the world 's largest silicon tracking detector at CERN in Geneva, Switzerland, had been successfully installed (see also ). Called the CMS (Compact Muon Solenoid) Silicon Strip Tracking Detector, the six-ton instrument has a total surface area of 205 square meters, about the same as a singles tennis court.

  4. UC Riverside physicists contribute to state-of-the-art detector installed in Switzerland

    CERN Multimedia

    2008-01-01

    UC Riverside scientists led by Gail Hanson, a distinguished professor of physics, are part of a collaboration of approximately 2300 international physicists who announced Dec. 19 that the world's largest silicon tracking detector at CERN in Geneva, Switzerland, had been successfully installed (see also ). Called the CMS (Compact Muon Solenoid) Silicon Strip Tracking Detector, the six-ton instrument has a total surface area of 205 square meters, about the same as a singles tennis court.

  5. Scientific productivity and academic promotion: a study on French and Italian physicists

    OpenAIRE

    Francesco Lissoni; Jacques Mairesse; Fabio Montobbio; Michele Pezzoni

    2011-01-01

    The article examines the determinants of scientific productivity (number of articles and journals' impact factor) for a panel of about 3600 French and Italian academic physicists active in 2004--2005. Endogeneity problems concerning promotion and productivity are addressed by specifying a generalized Tobit model, in which a selection probit equation accounts for the individual scientist's probability of promotion to her present rank, and a productivity regression estimates the effects of age,...

  6. Physicists to mark 20th anniversary of first string theory revolution

    CERN Document Server

    2004-01-01

    "Growing numbers of physicists see superstring theory as their best chance to formulate a set of natural laws that govern everything from the largest galaxies to the smallest quarks in one grand unifying theory of everything. The two men who started the revolution, Michael Green, now of the University of Cambridge, and John Schwarz of the California Institute of Technology, also will speak at the symposium" (1.5 pages)

  7. Physicists' views on hadrontherapy: a survey of members of the Italian Association of Medical Physics (AIFM).

    Science.gov (United States)

    Giandini, Tommaso; Tenconi, Chiara; Carrara, Mauro; Ciocca, Mario; Russo, Stefania; Panaino, Costanza M V; Cattani, Federica; Ciardo, Delia; Morlino, Sara; Avuzzi, Barbara; Bedini, Nice; Villa, Sergio; Marvaso, Giulia; Romanelli, Paola; Hasegawa, Azusa; Vischioni, Barbara; Valvo, Francesca; Jereczek-Fossa, Barbara A; Orecchia, Roberto; Valdagni, Riccardo; Pignoli, Emanuele

    2017-09-18

    This study was based on a survey to investigate perceptions of hadrontherapy of the members of the Italian Association of Medical Physics (AIFM). The survey was digitally submitted to the 991 members between the end of January and the beginning of April 2016. A 19-item questionnaire was designed focusing on advantages and disadvantages of hadrontherapy, current status and possible future improvements, and need and opportunities for future investments in Italy and abroad. Information about professional qualifications, main fields of clinical involvement and specific competencies of the respondents was also collected. The survey was completed by 121 AIFM members (response rate 12.2%). In the answers collected, it was shown that medical physicists expressed interest in hadrontherapy mainly for reasons of personal interest rather than for professional needs (90% ± 2.5% vs. 52% ± 4.3% of the respondents, respectively), with a good knowledge of the related basic aspects as well as of the pros and cons of its application. However, poor knowledge of the current status of hadrontherapy was observed among the medical physicists not directly involved at a professional level, who were less than 3% of the physicists working in radiotherapy. In light of these results, the implementation of new training and education initiatives should be devised to promote a deeper and global knowledge of hadrontherapy-related issues, not only from a theoretical point of view but also in practical terms. Moreover, a close collaboration between highly specialized medical physicists employed in hadrontherapy centers and others in oncology hospitals should be -encouraged.

  8. Children's speech recognition and loudness perception with the Desired Sensation Level v5 Quiet and Noise prescriptions.

    Science.gov (United States)

    Crukley, Jeffery; Scollie, Susan D

    2012-12-01

    To determine whether Desired Sensation Level (DSL) v5 Noise is a viable hearing instrument prescriptive algorithm for children, in comparison with DSL v5 Quiet. In particular, the authors compared children's performance on measures of consonant recognition in quiet, sentence recognition in noise, and loudness perception when fitted with DSL v5 Quiet and Noise. Eleven children (ages 8 to 17 years) with stable, congenital sensorineural hearing losses participated in the study. Participants were fitted bilaterally to DSL v5 prescriptions with behind-the-ear hearing instruments. The order of prescription was counterbalanced across participants. Repeated measures analysis of variance was used to compare performance between prescriptions. Use of the Noise prescription resulted in a significant decrease in consonant perception in Quiet with low-level input, but no difference with average-level input. There was no significant difference in sentence-in-noise recognition between the two prescriptions. Loudness ratings for input levels above 72 dB SPL were significantly lower with the noise prescription. Average-level consonant recognition in quiet was preserved and aversive loudness was alleviated by the Noise prescription relative to the quiet prescription, which suggests that the DSL v5 Noise prescription may be an effective approach to managing the nonquiet listening needs of children with hearing loss.

  9. Characteristics of seasonal variation and solar activity dependence of the geomagnetic solar quiet daily variation

    Science.gov (United States)

    Shinbori, A.; Koyama, Y.; Nose, M.; Hori, T.

    2017-12-01

    Characteristics of seasonal variation and solar activity dependence of the X- and Y-components of the geomagnetic solar quiet (Sq) daily variation at Memanbetsu in mid-latitudes and Guam near the equator have been investigated using long-term geomagnetic field data with 1-h time resolution from 1957 to 2016. In this analysis, we defined the quiet day when the maximum value of the Kp index is less than 3 for that day. In this analysis, we used the monthly average of the adjusted daily F10.7 corresponding to geomagnetically quiet days. For identification of the monthly mean Sq variation in the X and Y components (Sq-X and Sq-Y), we first determined the baseline of the X and Y components from the average value from 22 to 2 h (LT: local time) for each quiet day. Next, we calculated a deviation from the baseline of the X- and Y-components of the geomagnetic field for each quiet day, and computed the monthly mean value of the deviation for each local time. As a result, Sq-X and Sq-Y shows a clear seasonal variation and solar activity dependence. The amplitude of seasonal variation increases significantly during high solar activities, and is proportional to the solar F10.7 index. The pattern of the seasonal variation is quite different between Sq-X and Sq-Y. The result of the correlation analysis between the solar F10.7 index and Sq-X and Sq-Y shows almost the linear relationship, but the slope and intercept of the linear fitted line varies as function of local time and month. This implies that the sensitivity of Sq-X and Sq-Y to the solar activity is different for different local times and seasons. The local time dependence of the offset value of Sq-Y at Guam and its seasonal variation suggest a magnetic field produced by inter-hemispheric field-aligned currents (FACs). From the sign of the offset value of Sq-Y, it is infer that the inter-hemispheric FACs flow from the summer to winter hemispheres in the dawn and dusk sectors and from the winter to summer hemispheres in

  10. Brainstem auditory responses to resolved and unresolved harmonics of a synthetic vowel in quiet and noise.

    Science.gov (United States)

    Laroche, Marilyn; Dajani, Hilmi R; Prévost, François; Marcoux, André M

    2013-01-01

    This study investigated speech auditory brainstem responses (speech ABR) with variants of a synthetic vowel in quiet and in background noise. Its objectives were to study the noise robustness of the brainstem response at the fundamental frequency F0 and at the first formant F1, evaluate how the resolved/unresolved harmonics regions in speech contribute to the response at F0, and investigate the origin of the response at F0 to resolved and unresolved harmonics in speech. In total, 18 normal-hearing subjects (11 women, aged 18-33 years) participated in this study. Speech ABRs were recorded using variants of a 300 msec formant-synthesized /a/ vowel in quiet and in white noise. The first experiment employed three variants containing the first three formants F1 to F3, F1 only, and F2 and F3 only with relative formant levels following those reported in the literature. The second experiment employed three variants containing F1 only, F2 only, and F3 only, with the formants equalized to the same level and the signal-to-noise ratio (SNR) maintained at -5 dB. Overall response latency was estimated, and the amplitude and local SNR of the envelope following response at F0 and of the frequency following response at F1 were compared for the different stimulus variants in quiet and in noise. The response at F0 was more robust to noise than that at F1. There were no statistically significant differences in the response at F0 caused by the three stimulus variants in both experiments in quiet. However, the response at F0 with the variant dominated by resolved harmonics was more robust to noise than the response at F0 with the stimulus variants dominated by unresolved harmonics. The latencies of the responses in all cases were very similar in quiet, but the responses at F0 due to resolved and unresolved harmonics combined nonlinearly when both were present in the stimulus. Speech ABR has been suggested as a marker of central auditory processing. The results of this study support

  11. [Maria Goeppert-Mayer Award to Taiwan-born and raised American physicist Michele Ma Chung-pei

    CERN Multimedia

    2003-01-01

    "The American Physical Society conferred the prestigious Maria Goeppert-Mayer Award to Taiwan-born and raised American physicist Michele Ma Chung-pei recently in recognition of her important contributions to theoretical astrophysics" (1 page).

  12. The updated ESTRO core curricula 2011 for clinicians, medical physicists and RTTs in radiotherapy/radiation oncology.

    NARCIS (Netherlands)

    Eriksen, J.G.; Beavis, A.W.; Coffey, M.A.; Leer, J.W.H.; Magrini, S.M.; Benstead, K.; Boelling, T.; Hjalm-Eriksson, M.; Kantor, G.; Maciejewski, B.; Mezeckis, M.; Oliveira, A.; Thirion, P.; Vitek, P.; Olsen, D.R.; Eudaldo, T.; Enghardt, W.; Francois, P.; Garibaldi, C.; Heijmen, B.; Josipovic, M.; Major, T.; Nikoletopoulos, S.; Rijnders, A.; Waligorski, M.; Wasilewska-Radwanska, M.; Mullaney, L.; Boejen, A.; Vaandering, A.; Vandevelde, G.; Verfaillie, C.; Potter, R.

    2012-01-01

    INTRODUCTION: In 2007 ESTRO proposed a revision and harmonisation of the core curricula for radiation oncologists, medical physicists and RTTs to encourage harmonised education programmes for the professional disciplines, to facilitate mobility between EU member states, to reflect the rapid

  13. AN ANTHOLOGY OF THE DISTINGUISHED ACHIEVEMENTS IN SCIENCE AND TECHNIQUE. PART 31: PORTRAIT OF THE KHARKIV PHYSICIST ALEXANDER ILYICH AKHIEZER

    Directory of Open Access Journals (Sweden)

    M.I. Baranov

    2016-05-01

    Full Text Available Purpose. Description is in the short form of the basic distinguished scientific achievements, features of personality and way of life of the known Kharkov physicist-theorist A.I. Akhiezer. Methodology. Existent scientific approaches for treatment and systematization of physical knowledges. Methods of historical method at research of development in human society of basic sections of theoretical physics. Results. Short information is resulted about the basic creative and vital stages, and also fundamental scientific achievements of the indicated prominent physicist of the XX century. Some personal qualities of this Kharkov physicist-theorist, becoming a founder known in the world of physical school are described. Originality. First the Kharkov scientist-electro-physicist for the wide circle of readers imagined a short scientifically-historical essay the known physicist of contemporaneity, being based on his scientific labours and published materials about him. Practical value. Scientific popularization of creative activity of the known Kharkov physicist and his achievements in area of theoretical physics. Next reminder a wide reader on the example of creative life in science and got prominent scientific results of labour of one human personality known in the scientific world about incessant in modern society connection of times and generations.

  14. Magnetic Flux Cancellation as the Origin of Solar Quiet-region Pre-jet Minifilaments

    Energy Technology Data Exchange (ETDEWEB)

    Panesar, Navdeep K.; Sterling, Alphonse C.; Moore, Ronald L., E-mail: navdeep.k.panesar@nasa.gov [NASA Marshall Space Flight Center, Huntsville, AL 35812 (United States)

    2017-08-01

    We investigate the origin of 10 solar quiet-region pre-jet minifilaments , using EUV images from the Solar Dynamics Observatory ( SDO )/Atmospheric Imaging Assembly (AIA) and magnetograms from the SDO Helioseismic and Magnetic Imager (HMI). We recently found that quiet-region coronal jets are driven by minifilament eruptions, where those eruptions result from flux cancellation at the magnetic neutral line under the minifilament. Here, we study the longer-term origin of the pre-jet minifilaments themselves. We find that they result from flux cancellation between minority-polarity and majority-polarity flux patches. In each of 10 pre-jet regions, we find that opposite-polarity patches of magnetic flux converge and cancel, with a flux reduction of 10%–40% from before to after the minifilament appears. For our 10 events, the minifilaments exist for periods ranging from 1.5 hr to 2 days before erupting to make a jet. Apparently, the flux cancellation builds a highly sheared field that runs above and traces the neutral line, and the cool transition region plasma minifilament forms in this field and is suspended in it. We infer that the convergence of the opposite-polarity patches results in reconnection in the low corona that builds a magnetic arcade enveloping the minifilament in its core, and that the continuing flux cancellation at the neutral line finally destabilizes the minifilament field so that it erupts and drives the production of a coronal jet. Thus, our observations strongly support that quiet-region magnetic flux cancellation results in both the formation of the pre-jet minifilament and its jet-driving eruption.

  15. Nightside Quiet-Time Mid-Latitude Ionospheric Convection and Its Connection to Penetration Electric Fields

    Science.gov (United States)

    Ruohoniemi, J. M.; Maimaiti, M.; Baker, J. B.; Ribeiro, A. J.

    2017-12-01

    Previous studies have shown that during quiet geomagnetic conditions F-region subauroral ionospheric plasma exhibits drifts of a few tens of m/s, predominantly in the westward direction. However, the exact driving mechanisms for this plasma motion are still not well understood. Recent expansion of SuperDARN radars into the mid-latitude region has provided new opportunities to study subauroral ionospheric convection over large areas and with greater spatial resolution and statistical significance than previously possible. Mid-latitude SuperDARN radars tend to observe subauroral ionospheric backscatter with low Doppler velocities on most geomagnetically quiet nights. In this study, we have used two years of data obtained from the six mid-latitude SuperDARN radars in the North American sector to derive a statistical model of quiet-time nightside mid-latitude plasma convection between 52°- 58° magnetic latitude. The model is organized in MLAT-MLT coordinates and has a spatial resolution of 1°x 7 min with each grid cell typically counting thousands of velocity measurements. Our results show that the flow is predominantly westward (20 - 60 m/s) and weakly northward (0 -20 m/s) near midnight but with a strong seasonal dependence such that the flows tend to be strongest and most spatially variable in winter. These statistical results are in good agreement with previously reported observations from ISR measurements but also show some interesting new features, one being a significant latitudinal variation of zonal flow velocity near midnight in winter. In this presentation, we describe the derivation of the nightside quite-time subauroral convection model, analyze its most prominent features, and discuss the results in terms of the Ionosphere-Thermosphere coupling and penetration electric fields.

  16. IRIS Burst Spectra Co-spatial to a Quiet-Sun Ellerman-like Brightening

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, C. J.; Erdélyi, R. [Solar Physics and Space Plasma Research Centre, University of Sheffield, Hicks Building, Hounsfield Road, Sheffield, S3 7RH (United Kingdom); Freij, N.; Oliver, R. [Departament de Física, Universitat de les Illes Balears, E-07122 Palma de Mallorca (Spain); Reid, A.; Mathioudakis, M., E-mail: c.j.nelson@sheffield.ac.uk [Astrophysics Research Centre (ARC), School of Mathematics and Physics, Queens University, Belfast, BT7 1NN (United Kingdom)

    2017-08-10

    Ellerman bombs (EBs) have been widely studied over the past two decades; however, only recently have the counterparts of these events been observed in the quiet-Sun. The aim of this article is to further understand small-scale quiet-Sun Ellerman-like brightenings (QSEBs) through research into their spectral signatures, including investigating whether the hot signatures associated with some EBs are also visible co-spatial to any QSEBs. We combine H α and Ca ii 8542 Å line scans at the solar limb with spectral and imaging data sampled by the Interface Region Imaging Spectrograph ( IRIS ). Twenty-one QSEBs were identified with average lifetimes, lengths, and widths measured to be around 120 s, 0.″63, and 0.″35, respectively. Three of these QSEBs displayed clear repetitive flaring through their lifetimes, comparable to the behavior of EBs in active regions. Two QSEBs in this sample occurred co-spatial to increased emission in SDO /AIA 1600 Å and IRIS slit-jaw imager 1400 Å data; however, these intensity increases were smaller than those reported co-spatially with EBs. One QSEB was also sampled by the IRIS slit during its lifetime, displaying increases in intensity in the Si iv 1393 Å and Si iv 1403 Å cores, as well as the C ii and Mg ii line wings, analogous to IRIS bursts (IBs). Using RADYN simulations, we are unable to reproduce the observed QSEB H α and Ca ii 8542 Å line profiles, leaving the question of the temperature stratification of QSEBs open. Our results imply that some QSEBs could be heated to transition region temperatures, suggesting that IB profiles should be observed throughout the quiet-Sun.

  17. Searching for dark matter with neutron star mergers and quiet kilonovae

    Science.gov (United States)

    Bramante, Joseph; Linden, Tim; Tsai, Yu-Dai

    2018-03-01

    We identify new astrophysical signatures of dark matter that implodes neutron stars (NSs), which could decisively test whether NS-imploding dark matter is responsible for missing pulsars in the Milky Way galactic center, the source of some r -process elements, and the origin of fast-radio bursts. First, NS-imploding dark matter forms ˜10-10 solar mass or smaller black holes inside neutron stars, which proceed to convert neutron stars into ˜1.5 solar mass black holes (BHs). This decreases the number of neutron star mergers seen by LIGO/Virgo (LV) and associated merger kilonovae seen by telescopes like DES, BlackGEM, and ZTF, instead producing a population of "black mergers" containing ˜1.5 solar mass black holes. Second, dark matter-induced neutron star implosions may create a new kind of kilonovae that lacks a detectable, accompanying gravitational signal, which we call "quiet kilonovae." Using DES data and the Milky Way's r-process abundance, we constrain quiet kilonovae. Third, the spatial distribution of neutron star merger kilonovae and quiet kilonovae in galaxies can be used to detect dark matter. NS-imploding dark matter destroys most neutron stars at the centers of disc galaxies, so that neutron star merger kilonovae would appear mostly in a donut at large radii. We find that as few as ten neutron star merger kilonova events, located to ˜1 kpc precision could validate or exclude dark matter-induced neutron star implosions at 2 σ confidence, exploring dark matter-nucleon cross-sections 4-10 orders of magnitude below current direct detection experimental limits. Similarly, NS-imploding dark matter as the source of fast radio bursts can be tested at 2 σ confidence once 20 bursts are located in host galaxies by radio arrays like CHIME and HIRAX.

  18. Multi-epoch intranight optical monitoring of eight radio-quiet BL Lac candidates

    Science.gov (United States)

    Kumar, P.; Gopal-Krishna; Stalin, C. S.; Chand, H.; Srianand, R.; Petitjean, P.

    2017-10-01

    For a new sample of eight weak-line quasars (WLQs) we report a sensitive search in 20 intranight monitoring sessions, for blazar-like optical flux variations on hour-like and longer time-scale (day/month/year-like). The sample consists exclusively of the WLQs that are not radio-loud and either have been classified as 'radio-weak probable BL Lac candidates' and/or are known to have exhibited at least one episode of large, blazar-like optical variability. Whereas only a hint of intranight variability is seen for two of these WLQs, J104833.5+620305.0 (z = 0.219) and J133219.6+622715.9 (z = 3.15), statistically significant internight variability at a few per cent level is detected for three of the sources, including the radio-intermediate WLQ J133219.6+622715.9 (z = 3.15) and the well-known bona fide radio-quiet WLQs J121221.5+534128.0 (z = 3.10) and WLQ J153259.9-003944.1 (z = 4.62). In the rest frame, this variability is intraday and in the far-ultraviolet band. On the time-scale of a decade, we find for three of the WLQs large brightness changes, amounting to 1.655 ± 0.009, 0.163 ± 0.010 and 0.144 ± 0.018 mag, for J104833.5+620305.0, J123743.1+630144.9 and J232428.4+144324.4, respectively. Whereas the latter two are confirmed radio-quiet WLQs, the extragalactic nature of J104833.5+620305.0 remains to be well established, thanks to the absence of any feature(s) in its available optical spectra. This study forms a part of our ongoing campaign of intranight optical monitoring of radio-quiet WLQs, in order to improve the understanding of this enigmatic class of active galactic nuclei and to look among them for a possible tiny, elusive population of radio-quiet BL Lacs.

  19. Evidence for ultra-fast outflows in radio-quiet AGNs: III - location and energetics

    OpenAIRE

    Tombesi, F.; Cappi, M.; Reeves, J. N.; Braito, V.

    2012-01-01

    Using the results of a previous X-ray photo-ionization modelling of blue-shifted Fe K absorption lines on a sample of 42 local radio-quiet AGNs observed with XMM-Newton, in this letter we estimate the location and energetics of the associated ultra-fast outflows (UFOs). Due to significant uncertainties, we are essentially able to place only lower/upper limits. On average, their location is in the interval ~0.0003-0.03pc (~10^2-10^4 r_s) from the central black hole, consistent with what is exp...

  20. Correlation lifetimes of quiet and magnetic granulation from the SOUP instrument on Spacelab 2

    Science.gov (United States)

    Title, A.; Tarbell, T.; Topka, K.; Acton, L.; Duncan, D.; Ferguson, S.; Finch, M.; Frank, Z.; Kelly, G.; Lindgren, R.; Morrill, M.; Pope, T.; Reeves, R.; Rehse, R.; Shine, R.; Simon, G.; Harvey, J.; Leibacher, J.; Livingston, W.; November, L.; Zirker, J.

    The time sequences of diffraction limited granulation images obtained by the Solar Optical Universal Polarimeter on Spacelab 2 are presented. The uncorrection autocorrelation limetime in magnetic regions is dominated by the 5-min oscillation. The removal of this oscillation causes the autocorrelation lifetime to increase by more than a factor of 2. The results suggest that a significant fraction of granule lifetimes are terminated by nearby explosions. Horizontal displacements and transverse velocities in the intensity field are measured. Lower limits to the lifetime in the quiet and magnetic sun are set at 440 s and 950 s, respectively.

  1. Photospheric Magnetic Field Properties of Flaring versus Flare-quiet Active Regions. II. Discriminant Analysis

    Science.gov (United States)

    Leka, K. D.; Barnes, G.

    2003-10-01

    We apply statistical tests based on discriminant analysis to the wide range of photospheric magnetic parameters described in a companion paper by Leka & Barnes, with the goal of identifying those properties that are important for the production of energetic events such as solar flares. The photospheric vector magnetic field data from the University of Hawai'i Imaging Vector Magnetograph are well sampled both temporally and spatially, and we include here data covering 24 flare-event and flare-quiet epochs taken from seven active regions. The mean value and rate of change of each magnetic parameter are treated as separate variables, thus evaluating both the parameter's state and its evolution, to determine which properties are associated with flaring. Considering single variables first, Hotelling's T2-tests show small statistical differences between flare-producing and flare-quiet epochs. Even pairs of variables considered simultaneously, which do show a statistical difference for a number of properties, have high error rates, implying a large degree of overlap of the samples. To better distinguish between flare-producing and flare-quiet populations, larger numbers of variables are simultaneously considered; lower error rates result, but no unique combination of variables is clearly the best discriminator. The sample size is too small to directly compare the predictive power of large numbers of variables simultaneously. Instead, we rank all possible four-variable permutations based on Hotelling's T2-test and look for the most frequently appearing variables in the best permutations, with the interpretation that they are most likely to be associated with flaring. These variables include an increasing kurtosis of the twist parameter and a larger standard deviation of the twist parameter, but a smaller standard deviation of the distribution of the horizontal shear angle and a horizontal field that has a smaller standard deviation but a larger kurtosis. To support the

  2. Moths produce extremely quiet ultrasonic courtship songs by rubbing specialized scales

    DEFF Research Database (Denmark)

    Nakano, Ryo; Skals, Niels; Takanashi, Takuma

    2008-01-01

    level at 1 cm) adapted for private sexual communication in the Asian corn borer moth, Ostrinia furnacalis. During courtship, the male rubs specialized scales on the wing against those on the thorax to produce the songs, with the wing membrane underlying the scales possibly acting as a sound resonator....... The male's song suppresses the escape behavior of the female, thereby increasing his mating success. Our discovery of extremely low-intensity ultrasonic communication may point to a whole undiscovered world of private communication, using "quiet" ultrasound....

  3. Quiet: The Power of Introvert in a World That Can’t Stop Talking

    OpenAIRE

    Sean Schat

    2012-01-01

    Do you pay attention to the differences between extroversion and introversion? It can be fascinating to consider who is and is not aware of  the distinction between the two, as well as the significant formative role they both play in daily perceptions and interactions.  In my experience, more often than not it is the introverts who recognize and appreciate the difference, while too many extroverts remain unaware. In  Quiet: The Power of Introverts in a World That Can’t Stop Talking(2012), Sus...

  4. Solar quiet day ionospheric source current in the West African region.

    Science.gov (United States)

    Obiekezie, Theresa N; Okeke, Francisca N

    2013-05-01

    The Solar Quiet (Sq) day source current were calculated using the magnetic data obtained from a chain of 10 magnetotelluric stations installed in the African sector during the French participation in the International Equatorial Electrojet Year (IEEY) experiment in Africa. The components of geomagnetic field recorded at the stations from January-December in 1993 during the experiment were separated into the source and (induced) components of Sq using Spherical Harmonics Analysis (SHA) method. The range of the source current was calculated and this enabled the viewing of a full year's change in the source current system of Sq.

  5. Solar quiet day ionospheric source current in the West African region

    Directory of Open Access Journals (Sweden)

    Theresa N. Obiekezie

    2013-05-01

    Full Text Available The Solar Quiet (Sq day source current were calculated using the magnetic data obtained from a chain of 10 magnetotelluric stations installed in the African sector during the French participation in the International Equatorial Electrojet Year (IEEY experiment in Africa. The components of geomagnetic field recorded at the stations from January–December in 1993 during the experiment were separated into the source and (induced components of Sq using Spherical Harmonics Analysis (SHA method. The range of the source current was calculated and this enabled the viewing of a full year’s change in the source current system of Sq.

  6. Variation of the quiet sun at 21 cm - 1981-1987

    International Nuclear Information System (INIS)

    Bastian, T.S.; Dulk, G.A.

    1988-01-01

    The sun was imaged at a wavelength of about 21 cm during 1981-1987 using the VLA, the Green Bank 91-m telescope, the Arecibo 305 m telescope, and powerful maximum entropy image reconstruction techniques. There was a systematic decrease in the quiet sun's brightness temperature at 21 cm as the sun declined from sunspot maximum to sunspot minimum; this was accompanied by a systematic decrease in the sun's radius. The two-fold decrease in the electron number density in the solar transition region and low corona could have been the cause of these variations. 7 references

  7. Report on student participants at the 2003 Annual Meeting of the National Society of Black Physicists

    Energy Technology Data Exchange (ETDEWEB)

    Julius Dollison, Michael Neuchatz

    2003-07-01

    The first meeting of African American physicists was held in 1973 at Fisk University in Nashville, Tennessee, with around 50 Black physicists in attendance. In 1977, this organization was formally established as the National Society of Black Physicists (NSBP) out of a need to address many concerns of African American physicists. During the ensuing years the Conference began to grow and was hosted by different institutions at various geographic locations. This year, the 2003 Annual Conference of the National Society of Black Physicists and Black Physics Students was hosted by Spelman College in Atlanta, Georgia during the weekend of February 12th-15th, 2003. This Conference brought together over 500 African American physics students and working physicists. Also attending were corporate and graduate school recruiters, administrators, professional society representatives and others concerned with the small representation of minorities in the field of physics. The organizers of the Conference contracted with the Statistical Research Center of the American Institute of Physics to conduct a formal evaluative study of the meeting, resulting in this report. The evaluation questionnaire was designed by the organizers of the NSBP conference with input from the Statistical Research Center's staff. It included questions on the students' backgrounds and demographic characteristics, physics research experience, career goals, challenges faced in their academic pursuits, and ratings of various aspects of the conference. The questionnaire was distributed at the conference when the students signed in. Of the 330 students who were registered, roughly 304 attended and were given the four-page questionnaire to complete. Responses were collected on the last night of the conference, with 172 (approximately 57%) returning completed questionnaires. This low response rate could be attributed in part to the fact that respondents were asked to provide possibly sensitive personal

  8. Radiation protection in hospitals : the figure of the physicist in hospital

    International Nuclear Information System (INIS)

    Rodriguez P, M.

    2008-12-01

    Currently in the country there is not certification to serve as physicist of hospital, only require a degree of physical or related occupation (often engineering), and having gone through a few training of 6 months in hospital. Unlike in the U.S. should have a certification by the American Board of Radiology and the American Board of Medical Physics. It also must cover a postdoctoral residency in hospital at least two years in which it goes through a training that is paid. In the United Kingdom requires a university degree in Physics or career in order, is required to complete a program of four years in total (2 of theoretical and 2 of clinical practice) certified by the Institute of Physics and Engineering in Medicine, during which is also going through a training wage. Medical physicists in Canada are certified by the Canadian College of Physicists in Medicine by written examinations, which must be renewed every 5 years and have experience in the clinical setting. While in Spain, the basic requirement is to have a university degree in physics or related sciences and the certification is awarded by the Ministry of Education and Science which is due to participate in a test at the national level to a hospital residence of 3 years. One of the main aspects that require the clinical training is due to accidents caused by deficiencies in the training of responsible professionals. Examples include the Panama accident with 28 overexposed patients in 2001 and the accident of 1997 in Costa Rica. In the human resources training is needed to focus on written procedures for quality assurance of equipment, verification of processing systems, incorporating changes and improvements in the procedures themselves, keeping the workload at an acceptable level (many of errors are due to the haste with which the work must be done), medical surveillance of patients, dosimetry in vivo, and to generate recommendations to regulatory authorities. (Author)

  9. Views of a physicist selected papers of N G van Kampen

    CERN Document Server

    Meijer, Paul Herman E

    2000-01-01

    N G van Kampen is a well-known theoretical physicist who has had a long and distinguished career. His research covers scattering theory, plasma physics, statistical mechanics, and various mathematical aspects of physics. In addition to his scientific work, he has written a number of papers about more general aspects of science. An indefatigable fighter for intellectual honesty and clarity, he has pointed out repeatedly that the fundamental ideas of physics have been needlessly obscured.As those papers appeared in various journals, partly in Dutch, it was felt that it would be worthwhile to col

  10. Differential geometry for physicists and mathematicians moving frames and differential forms : from Euclid past Riemann

    CERN Document Server

    Vargas, José G

    2014-01-01

    This is a book that the author wishes had been available to him when he was student. It reflects his interest in knowing (like expert mathematicians) the most relevant mathematics for theoretical physics, but in the style of physicists. This means that one is not facing the study of a collection of definitions, remarks, theorems, corollaries, lemmas, etc. but a narrative - almost like a story being told - that does not impede sophistication and deep results. It covers differential geometry far beyond what general relativists perceive they need to know. And it introduces readers to other areas

  11. PPPC 4 DM secondary: a Poor Particle Physicist Cookbook for secondary radiation from Dark Matter

    Energy Technology Data Exchange (ETDEWEB)

    Buch, Jatan [Institut de Physique Théorique, Université Paris Saclay, CNRS, CEA,F-91191 Gif-sur-Yvette (France); Department of Physics, Indian Institute of Technology,Kharagpur, West Bengal - 721302 (India); Cirelli, Marco; Giesen, Gaëlle; Taoso, Marco [Institut de Physique Théorique, Université Paris Saclay, CNRS, CEA,F-91191 Gif-sur-Yvette (France)

    2015-09-11

    We enlarge the set of recipes and ingredients at disposal of any poor particle physicist eager to cook up signatures from weak-scale Dark Matter models by computing two secondary emissions due to DM particles annihilating or decaying in the galactic halo, namely the radio signals from synchrotron emission and the gamma rays from bremsstrahlung. We consider several magnetic field configurations and propagation scenarios for electrons and positrons. We also provide an improved energy loss function for electrons and positrons in the Galaxy, including synchrotron losses in the different configurations, bremsstrahlung losses, ionization losses and Inverse Compton losses with an updated InterStellar Radiation Field.

  12. PPPC 4 DM secondary: a Poor Particle Physicist Cookbook for secondary radiation from Dark Matter

    Energy Technology Data Exchange (ETDEWEB)

    Buch, Jatan; Cirelli, Marco; Giesen, Gaëlle; Taoso, Marco, E-mail: jbuch.iitkgp@gmail.com, E-mail: marco.cirelli@cea.fr, E-mail: gaelle.giesen@cea.fr, E-mail: marco.taoso@cea.fr [Institut de Physique Théorique, Université Paris Saclay, CNRS, CEA, F-91191 Gif-sur-Yvette (France)

    2015-09-01

    We enlarge the set of recipes and ingredients at disposal of any poor particle physicist eager to cook up signatures from weak-scale Dark Matter models by computing two secondary emissions due to DM particles annihilating or decaying in the galactic halo, namely the radio signals from synchrotron emission and the gamma rays from bremsstrahlung. We consider several magnetic field configurations and propagation scenarios for electrons and positrons. We also provide an improved energy loss function for electrons and positrons in the Galaxy, including synchrotron losses in the different configurations, bremsstrahlung losses, ionization losses and Inverse Compton losses with an updated InterStellar Radiation Field.

  13. Serving Physicists and the STEM Community: What is the Future of the Science Library?

    Science.gov (United States)

    Besara, Rachel

    2014-03-01

    What are the academic work behaviors and needs of physicists and the STEM Community? How are science libraries already used? What assumptions and approaches to information access and control need to be challenged? What does this mean for the future of library support for physics? These are just some of the questions being addressed by research at Florida State University Libraries. Learn how the findings of these studies addresses these questions and what the findings could mean for the future of library support for science research and teaching.

  14. The night of the physicists. Heisenberg, Hahn, Weizsaecker, and the German bomb

    International Nuclear Information System (INIS)

    Schirach, Richard von

    2014-01-01

    Finally the German atomic physicists around Heisenberg, von Weizsaecker, and Hahn worked on their ''uranium machine'' in a Swabian beer-cellar - and took themselves for the world elite of nuclear research. In imprisonment they heared from the dropping of the Hiroshima bomb - a shock. Richard von Schirach shows the hindered ''fathers of the German atomic bomb'' in close-up, their eagerness, their hybris, their true importance, and their attempts to give after the war a new interpretation of their own role. A book, which raises in the sense of Duerrenmatt the question for the responsibility of science.

  15. PPPC 4 DM secondary: a Poor Particle Physicist Cookbook for secondary radiation from Dark Matter

    International Nuclear Information System (INIS)

    Buch, Jatan; Cirelli, Marco; Giesen, Gaëlle; Taoso, Marco

    2015-01-01

    We enlarge the set of recipes and ingredients at disposal of any poor particle physicist eager to cook up signatures from weak-scale Dark Matter models by computing two secondary emissions due to DM particles annihilating or decaying in the galactic halo, namely the radio signals from synchrotron emission and the gamma rays from bremsstrahlung. We consider several magnetic field configurations and propagation scenarios for electrons and positrons. We also provide an improved energy loss function for electrons and positrons in the Galaxy, including synchrotron losses in the different configurations, bremsstrahlung losses, ionization losses and Inverse Compton losses with an updated InterStellar Radiation Field

  16. No-nonsense physicist an overview of Gabriele Giuliani’s work and life

    CERN Document Server

    Vignale, Giovanni; Pellegrini, Vittorio; Jain, Jainendra

    2016-01-01

    This book presents a compact personal biography and a collection of works by Gabriele F. Giuliani - a distinguished condensed matter theorist who made important contributions to our understanding of collective effects in electronic materials. In 2012 he passed away after a long battle with cancer. In addition, the book features scientific contributions from some of Prof. Giuliani's former students and collaborators and a number of personal recollections by friends and colleagues which shed light on the complex, multifaceted personality of a physicist who was also a passionate soccer player and formula Ford pilot.

  17. Characteristics of Relocated Quiet Zones Using Virtual Microphone Algorithm in an Active Headrest System

    Directory of Open Access Journals (Sweden)

    Seokhoon Ryu

    2016-01-01

    Full Text Available This study displays theoretical and experimental investigation on the characteristics of the relocated zone of quiet by a virtual microphone (VM based filtered-x LMS (FxLMS algorithm which can be embedded in a real-time digital controller for an active headrest system. The attenuation changes at the relocated zones of quiet by the variation of the distance between the ear and the error microphone are mainly examined. An active headrest system was implemented for the control experiment at a chair and consists of two (left and right secondary loudspeakers, two error microphones, two observer microphones at ear positions in a HATS, and other electronics including a dSPACE 1401 controller. The VM based FxLMS algorithm achieved an attenuation of about 22 dB in the control experiment against a narrowband primary noise by the variation of the distance between the ear and the error microphone. The important factors for the algorithm are discussed as well.

  18. Ion transport and loss in the earth's quiet ring current. I - Data and standard model

    Science.gov (United States)

    Sheldon, R. B.; Hamilton, D. C.

    1993-01-01

    A study of the transport and loss of ions in the earth's quiet time ring current, in which the standard radial diffusion model developed for the high-energy radiation belt particles is compared with the measurements of the lower-energy ring current ions, is presented. The data set provides ionic composition information in an energy range that includes the bulk of the ring current energy density, 1-300 keV/e. Protons are found to dominate the quiet time energy density at all altitudes, peaking near L of about 4 at 60 keV/cu cm, with much smaller contributions from O(+) (1-10 percent), He(+) (1-5 percent), and He(2+) (less than 1 percent). A minimization procedure is used to fit the amplitudes of the standard electric radial diffusion coefficient, yielding 5.8 x 10 exp -11 R(E-squared)/s. Fluctuation ionospheric electric fields are suggested as the source of the additional diffusion detected.

  19. Wave-filter-based approach for generation of a quiet space in a rectangular cavity

    Science.gov (United States)

    Iwamoto, Hiroyuki; Tanaka, Nobuo; Sanada, Akira

    2018-02-01

    This paper is concerned with the generation of a quiet space in a rectangular cavity using active wave control methodology. It is the purpose of this paper to present the wave filtering method for a rectangular cavity using multiple microphones and its application to an adaptive feedforward control system. Firstly, the transfer matrix method is introduced for describing the wave dynamics of the sound field, and then feedforward control laws for eliminating transmitted waves is derived. Furthermore, some numerical simulations are conducted that show the best possible result of active wave control. This is followed by the derivation of the wave filtering equations that indicates the structure of the wave filter. It is clarified that the wave filter consists of three portions; modal group filter, rearrangement filter and wave decomposition filter. Next, from a numerical point of view, the accuracy of the wave decomposition filter which is expressed as a function of frequency is investigated using condition numbers. Finally, an experiment on the adaptive feedforward control system using the wave filter is carried out, demonstrating that a quiet space is generated in the target space by the proposed method.

  20. The energy balance in coronal holes and average quiet-sun regions

    Science.gov (United States)

    Raymond, J. C.; Doyle, J. G.

    1981-01-01

    Emission measure curves are presented for average coronal hole and quiet-sun spectra taken during the Skylab mission by Vernazza and Reeves (1978), and the curves are used to discuss the energy balance in each region. Close-coupling calculations are used for the Be sequence, assuming a 10 level ion; for B sequence ions mainly distorted wave calculations in an 11 level ion are used, but close-coupling cross sections are used for some ions; for C and Mg sequence ions, distorted wave calculations are used with 15 and 10 level ions, respectively, and close-coupling results are used for Li-like ions with two levels. Results are presented and include the following: the coronal hole spectrum shows a smaller slope in the emission measure distribution, consistent with the expected outflow effects. It is concluded that the simple constant pressure models of static coronal loops of constant cross section are basically able to match the observed emission measure distribution of the average quiet sun between 1,000,000 and 10,000,000 K. However, the cell center and network distributions are respectively steeper and shallower than predicted by the detailed cooling curve.

  1. The Maximum Entropy Limit of Small-scale Magnetic Field Fluctuations in the Quiet Sun

    Science.gov (United States)

    Gorobets, A. Y.; Berdyugina, S. V.; Riethmüller, T. L.; Blanco Rodríguez, J.; Solanki, S. K.; Barthol, P.; Gandorfer, A.; Gizon, L.; Hirzberger, J.; van Noort, M.; Del Toro Iniesta, J. C.; Orozco Suárez, D.; Schmidt, W.; Martínez Pillet, V.; Knölker, M.

    2017-11-01

    The observed magnetic field on the solar surface is characterized by a very complex spatial and temporal behavior. Although feature-tracking algorithms have allowed us to deepen our understanding of this behavior, subjectivity plays an important role in the identification and tracking of such features. In this paper, we continue studies of the temporal stochasticity of the magnetic field on the solar surface without relying either on the concept of magnetic features or on subjective assumptions about their identification and interaction. We propose a data analysis method to quantify fluctuations of the line-of-sight magnetic field by means of reducing the temporal field’s evolution to the regular Markov process. We build a representative model of fluctuations converging to the unique stationary (equilibrium) distribution in the long time limit with maximum entropy. We obtained different rates of convergence to the equilibrium at fixed noise cutoff for two sets of data. This indicates a strong influence of the data spatial resolution and mixing-polarity fluctuations on the relaxation process. The analysis is applied to observations of magnetic fields of the relatively quiet areas around an active region carried out during the second flight of the Sunrise/IMaX and quiet Sun areas at the disk center from the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory satellite.

  2. Quiet comfort: noise, otherness, and the mobile production of personal space.

    Science.gov (United States)

    Hagood, Mack

    2011-01-01

    Marketing, news reports, and reviews of Bose QuietComfort noise-canceling headphones position them as essential gear for the mobile rational actor of the neoliberal market—the business traveler. This article concerns noise-canceling headphones’ utility as soundscaping devices, which render a sense of personal space by mediating sound. The airplane and airport are paradoxical spaces in which the pursuit of freedom impedes its own enjoyment. Rather than fight the discomforts of air travel as a systemic problem, travelers use the tactic of soundscaping to suppress the perceived presence of others. Attention to soundscaping enables the scholar to explore relationships between media, space, freedom, otherness, and selfhood in an era characterized by neoliberalism and increased mobility. Air travel is a moment in which people with diverse backgrounds, beliefs, and bodies crowd together in unusually close proximity. Noise is the sound of individualism and difference in conflict. Noise is othered sound, and like any type of othering, the perception of noise is socially constructed and situated in hierarchies of race, class, age, and gender. The normative QuietComfort user in media representations is white, male, rational, monied, and mobile; women, children, and “chatty” passengers are cast as noisemakers. Moreover, in putting on noise-canceling headphones, diverse selves put on the historically Western subjectivity that has been built into their technology, one that suppresses the noise of difference in favor of the smooth circulation of people, information, and commodities.

  3. Enhancement of low energy particle flux around plasmapause under quiet geomagnetic condition

    Science.gov (United States)

    Lee, J.

    2016-12-01

    Plasmapause is the boundary of the plasmaspheric region where cold plasma is dominant. In this boundary, the plasma density shows depletion to 1 10 on direction from the plasmasphere to magnetosphere and changes composition of energy distribution of particle. Some previous study provides that the location of the plasmapause expand beyond geosynchronous orbit under the quiet geomagnetic conditions. In this work, we study the changed characteristic of particle flux around the plasmapause using measurement from Van Allen Probes. On 23 April 2013, the satellites observed simultaneously proton and electron fluxes enhancement with E > 100 eV. During 12 hours prior to this event, the geomagnetic conditions were very quiet, Kp < 1, and geomagnetic storm did not occur. This event maintain for 15 minutes and only proton flux decrease rapidly in the magnetosphere. In this period SYM-H index enhanced abruptly in response to the impact of the dynamic pressure enhancement and AE index increased gradually up to about 200 nT. Electric field started to perturb in coincidence with enhancement of particle flux from the plasmapause. To explain the variation of low energy particle flux we will compare kinetic property of low energy particle by using velocity space distribution function at region of inner and outer boundary of the plasmapause.

  4. Force Plate Assessment of Quiet Standing Balance Control: Perspectives on Clinical Application within Stroke Rehabilitation

    Directory of Open Access Journals (Sweden)

    Avril Mansfield

    2015-01-01

    Full Text Available Assessment of balance control is essential to guide physical rehabilitation poststroke. However, current observational assessment tools available to physiotherapists provide limited information about underlying dyscontrol. This paper describes a force plate-based assessment of quiet standing balance control that we have implemented for individuals attending inpatient stroke rehabilitation. The assessment uses two force plates to measure location of ground reaction forces to maintain stability in quiet standing in five conditions (eyes open, eyes closed, standing symmetrically, and maximal loading on the less-affected and more-affected limbs. Measures of interest are variability of the centers of pressure under each foot and both feet combined, weight-bearing asymmetry, and correlation of center of pressure fluctuations between limbs. We present representative values for the above-mentioned measures and case examples to illustrate how the assessment can reveal patient-specific balance control problems and direct treatment. We identify limitations to our current assessment and recommendations for future research.

  5. Complexity and dynamics of switched human balance control during quiet standing.

    Science.gov (United States)

    Nema, Salam; Kowalczyk, Piotr; Loram, Ian

    2015-10-01

    In this paper, we use a combination of numerical simulations, time series analysis, and complexity measures to investigate the dynamics of switched systems with noise, which are often used as models of human balance control during quiet standing. We link the results with complexity measures found in experimental data of human sway motion during quiet standing. The control model ensuring balance, which we use, is based on an act-and-wait control concept, that is, a human controller is switched on when a certain sway angle is reached. Otherwise, there is no active control present. Given a time series data, we determine how does it look a typical pattern of control strategy in our model system. We detect the switched nonlinearity in the system using a frequency analysis method in the absence of noise. We also analyse the effect of time delay on the existence of limit cycles in the system in the absence of noise. We perform the entropy and detrended fluctuation analyses in view of linking the switchings (and the dead zone) with the occurrences of complexity in the model system in the presence of noise. Finally, we perform the entropy and detrended fluctuation analyses on experimental data and link the results with numerical findings in our model example.

  6. THE QUIET SOLAR ATMOSPHERE OBSERVED AND SIMULATED IN Na I D1

    International Nuclear Information System (INIS)

    Leenaarts, J.; Rutten, R. J.; Carlsson, M.; Hansteen, V.; Reardon, K.

    2010-01-01

    The Na I D 1 line in the solar spectrum is sometimes attributed to the solar chromosphere. We study its formation in quiet-Sun network and internetwork. We first present high-resolution profile-resolved images taken in this line with the imaging spectrometer Interferometric Bidimensional Spectrometer at the Dunn Solar Telescope and compare these to simultaneous chromospheric images taken in Ca II 8542 A and Hα. We then model Na I D 1 formation by performing three-dimensional (3D) non-local thermodynamic equilibrium profile synthesis for a snapshot from a 3D radiation-magnetohydrodynamics simulation. We find that most Na I D 1 brightness is not chromospheric but samples the magnetic concentrations that make up the quiet-Sun network in the photosphere, well below the height where they merge into chromospheric canopies, with aureoles from 3D resonance scattering. The line core is sensitive to magneto-acoustic shocks in and near magnetic concentrations, where shocks occur deeper than elsewhere, and may provide evidence of heating deep within magnetic concentrations.

  7. The difference between radio-loud and radio-quiet active galaxies

    Science.gov (United States)

    Wilson, A. S.; Colbert, E. J. M.

    1995-01-01

    The recent development of unified theories of active galactic nuclei (AGNs) has indicated that there are two physically distinct classes of these objects--radio-loud and radio-quiet. Despite differences, the (probable) thermal emissions from the AGNs (continua and lines from X-ray to infrared wavelengths) are quite similar to the two classes of object. We argue that this last result suggests that the black hole masses and mass accretion rates in the two classes are not greatly different, and that the difference between the classes is associated with the spin of the black hole. We assume that the normal process of accretion through a disk does not lead to rapidly spinning holes and propose that galaxies (e.g., spirals) which have not suffered a recent major merger event contain nonrotating or only slowly rotating black holes. When two such galaxies merge, the two black holes are known to form a binary and we assume that they eventually coalesce. The ratio of the number of radio-loud to radio-quiet AGNs at a given thermal (e.g., optical) luminosity is determined by the galaxy merger rate. Comparisons between the predicted and observed radio luminosity functions constrain the efficiencies with which jet power is extracted from the spinning hole and radio emission is produced by the jet.

  8. Empirical forecast of quiet time ionospheric Total Electron Content maps over Europe

    Science.gov (United States)

    Badeke, Ronny; Borries, Claudia; Hoque, Mainul M.; Minkwitz, David

    2018-06-01

    An accurate forecast of the atmospheric Total Electron Content (TEC) is helpful to investigate space weather influences on the ionosphere and technical applications like satellite-receiver radio links. The purpose of this work is to compare four empirical methods for a 24-h forecast of vertical TEC maps over Europe under geomagnetically quiet conditions. TEC map data are obtained from the Space Weather Application Center Ionosphere (SWACI) and the Universitat Politècnica de Catalunya (UPC). The time-series methods Standard Persistence Model (SPM), a 27 day median model (MediMod) and a Fourier Series Expansion are compared to maps for the entire year of 2015. As a representative of the climatological coefficient models the forecast performance of the Global Neustrelitz TEC model (NTCM-GL) is also investigated. Time periods of magnetic storms, which are identified with the Dst index, are excluded from the validation. By calculating the TEC values with the most recent maps, the time-series methods perform slightly better than the coefficient model NTCM-GL. The benefit of NTCM-GL is its independence on observational TEC data. Amongst the time-series methods mentioned, MediMod delivers the best overall performance regarding accuracy and data gap handling. Quiet-time SWACI maps can be forecasted accurately and in real-time by the MediMod time-series approach.

  9. The medical physicist: Criteria and recommendations for their academic training, clinical training and certification in Latin America

    International Nuclear Information System (INIS)

    2010-01-01

    During the last decade, the International Atomic Energy Agency (IAEA) has promoted a considerable number of technical cooperation activities and regular program linked to the establishment of educational programs in radiophysical medicine in Latin America. Despite these efforts, the amount of medical physicists in the various areas of radiological medicine (radiotherapy, nuclear medicine, radiodiagnosis) remains insufficient. In addition, many medical physicists currently associated with hospitals have inadequate training, and professional conditions (situation, salary, etc.) are very far from those of their colleagues in industrialized countries. This will result in the profession of clinical medical physicist not sufficiently attractive in Latin America. The medium-term projections indicate that the continuous evolution toward a medical care based increasingly on high technology will require even more well-trained medical physicists, thereby exacerbating the current situation. In response to the problems exposed, and considering the keen interest of the Member States of the IAEA to find a consensus solution, and an effective cooperation that would enable them to solve this problem, the ARCAL project LXXXIII was launched in 2005, strengthening the performance of medical physicists in Latin America. As part of its activities is a group of experts with the task of evaluating the problem of medical physics in the region and to develop recommendations, which are contained in this document, for harmonizing training and professional recognition of medical physicists. For the Pan American Health Organization (PAHO), medical physics is an area of special attention. For many years it has been promoting safe and effective use of radiation in health and giving technical advice to the ministries of health of Latin America and Caribbean region, in this field. Taking, therefore, on account the common interest of the IAEA and PAHO by tackling this problem, the historic and

  10. Clinical Training of Medical Physicists Specializing in Nuclear Medicine (Spanish Edition); Capacitacion clinica de fisicos medicos especialistas en medicina nuclear

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-07-15

    The application of radiation in human health, for both diagnosis and treatment of disease, is an important component of the work of the IAEA. The responsibility for the increasingly technical aspects of this work is undertaken by the medical physicist. To ensure good practice in this vital area, structured clinical training programmes are required to complement academic learning. This publication is intended to be a guide to the practical implementation of such a programme for nuclear medicine. There is a general and growing awareness that radiation medicine is increasingly dependent on well trained medical physicists who are based in a clinical setting. However an analysis of the availability of medical physicists indicates a large shortfall of qualified and capable professionals. This is particularly evident in developing countries. While strategies to increase educational opportunities are critical to such countries, the need for guidance on structured clinical training was recognized by the members of the Regional Cooperative Agreement for Research, Development and Training related to Nuclear Science and Technology (RCA) for the Asia-Pacific region. Consequently, a technical cooperation regional project (RAS6038) under the RCA programme was formulated to address this need in this region by developing suitable material and establishing its viability. Development of a clinical training guide for medical physicists specialising in nuclear medicine was started in 2009 with the appointment of a core drafting committee of regional and international experts. The publication drew on the experience of clinical training in Australia, Croatia and Sweden and was moderated by physicists working in the Asian region. The present publication follows the approach of earlier IAEA publications in the Training Course Series, specifically Nos 37 and 47, Clinical Training of Medical Physicists Specializing in Radiation Oncology and Clinical Training of Medical Physicists

  11. Redefining the Poet as Healer: Valerie Gillies's Collaborative Role in the Edinburgh Marie Curie Hospice Quiet Room Project.

    Science.gov (United States)

    Severin, Laura

    2015-01-01

    This article examines the poetic contribution of Valerie Gillies, Edinburgh Makar (or poet of the city) from 2005-2008, to the Edinburgh Marie Curie Hospice Quiet Room, a new contemplation space for patients, families, and staff. In collaboration with others, Gillies created a transitional space for the Quiet Room, centered on the display of her sonnet, "A Place Apart." This space functions to comfort visitors to the Quiet Room by relocating them in their surroundings and offering the solace provided by nature and history. With this project, her first as Edinburgh Makar, Gillies redefines the role of the poet as healer and advocates for newer forms of palliative care that focus on patients' spiritual and emotional, as well as physical, wellbeing.

  12. The changing role of health physicists as reflected by changes in professional health physics training courses

    International Nuclear Information System (INIS)

    Brown, L.D.

    1996-01-01

    Health Physics is a profession with long, honourable traditions; and this paper could be subtitled 'Health Physics - The First 100 Years'. The discovery of X-rays by Conrad Roentgen in 1895 and of natural radioactivity by Henri Becquerel in 1896, was followed two years later by the isolation of radium by Marie and Pierre Curie and then during the last years of the nineteenth century, by explosive world wide growth in the utilisation of both these new discoveries for medical diagnostic and therapeutic purposes The fact that these new medical tools carried associated risks was very quickly learned. Physicians who most enthusiastically adopted them often experienced severe skin injuries to heavily exposed digits, and there are numerous photographs of the hands of such individuals after experiencing several amputations. Regrettably mans ultimately fatal radiation induced cancers also began to appear before the end of the last century, by the first world par there were 200 of these and the death toll already exceeded 50. In the face of this two edged weapon it is not surprising that many of the physicians and medical physicists working in this area turned a great deal of their attention from the exploitation of the new technologies to the protection of their colleagues. These individuals were the pioneer health physicists and. although this name was not used at the time, their background experience in both medicine and physics laid scientific foundations for the new discipline which have remained its keystone ever since. (author)

  13. Women Physicists Speak: The 2001 International Study of Women in Physics

    Science.gov (United States)

    Ivie, Rachel; Czujko, Roman; Stowe, Katie

    2002-09-01

    The Working Group on Women in Physics of the International Union of Pure and Applied Physics (IUPAP) subcontracted with the Statistical Research Center of the American Institute of Physics (AIP) to conduct an international study on women in physics. This study had two parts. First, we conducted a benchmarking study to identify reliable sources and collect data on the representation of women in physics in as many IUPAP member countries as possible. Second, we conducted an international survey of individual women physicists. The survey addressed issues related to both education and employment. On the education side, we asked about experiences and critical incidents from secondary school through the highest degree earned. On the employment side, we asked about how the respondents' careers had evolved and their self-assessment of how well their careers had progressed. In addition, the questionnaire also addressed issues that cut across education and employment, such as the impact of marriage and children, the factors that contributed the most toward the success they had achieved to date, and suggestions for what could be done to improve the situation of women physicists.

  14. How in the 20th century physicists, chemists and biologists answered the question: what is life?

    International Nuclear Information System (INIS)

    Reutov, Valentin P; Schechter, A N

    2010-01-01

    The most essential achievements in 20th century biology are analyzed and the question of how throughout the last century physicists, chemists and biologists answered the question 'What is life?' is considered. The most considerable scientific achievement of 20th century biology, and perhaps of all science, is considered by many to be the discovery by biologist J Watson and physicists F Crick and M Wilkins that resulted in establishing the DNA structure. The related work of well-known scientists of the USA and Europe, E Schroedinger, L Pauling, M Perutz, J Kendrew, and of the Russian scientists N K Koltsov, N V Timofeeff-Ressovsky, G A Gamow, A M Olovnikov, is analyzed. Presently, when the structure of DNA, the process of gene expression and even the genomes of human beings are already known, scientists realize that we still do not know many of the most important things. In our opinion, the 20th century studies of nucleic acids largely ignored the principle of the cyclic organisation of DNA. In this connection, we analyze the principle of cyclicity, which in its generality may well complement the concept of the atomic structure of matter. (from the history of physics)

  15. Training requirements for health physicists in the decontamination/decommissioning field

    International Nuclear Information System (INIS)

    Copenhaver, E.D.; Parzyck, D.C.

    1986-01-01

    While a significant decrease in the number of new facilities requiring health physics surveillance has occurred in the past decade, there has been a tremendous increase in the need for health physicists to fill regulatory requirements at existing facilities and the Decontamination and Decommissioning requirements of older facilities nearing the end of their operational lifetime. There is a continuing long-term need to provide trained health physicists with the special skills to meet these requirements. Decontamination and decommissioning programs require both basic and specialized health physics activities to be performed (1) to evaluate the radiation environment of the facility under consideration, (2) to establish the standards to which cleanup activities must be pursued, and (3) to adequately protect the personnel involved in the cleanup. Performance-based training, based on job task analysis, is an appropriate way to define the different types of health physics expertise required for D and D programs. Materials have been developed to describe potential job requirements in the radiation protection field, and the appropriate training goals to meet these requirements. 14 refs., 3 tabs

  16. How in the 20th century physicists, chemists and biologists answered the question: what is life?

    Energy Technology Data Exchange (ETDEWEB)

    Reutov, Valentin P [Institute for Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow (Russian Federation); Schechter, A N [National Institutes of Health, Bethesda, Maryland (United States)

    2010-07-08

    The most essential achievements in 20th century biology are analyzed and the question of how throughout the last century physicists, chemists and biologists answered the question 'What is life?' is considered. The most considerable scientific achievement of 20th century biology, and perhaps of all science, is considered by many to be the discovery by biologist J Watson and physicists F Crick and M Wilkins that resulted in establishing the DNA structure. The related work of well-known scientists of the USA and Europe, E Schroedinger, L Pauling, M Perutz, J Kendrew, and of the Russian scientists N K Koltsov, N V Timofeeff-Ressovsky, G A Gamow, A M Olovnikov, is analyzed. Presently, when the structure of DNA, the process of gene expression and even the genomes of human beings are already known, scientists realize that we still do not know many of the most important things. In our opinion, the 20th century studies of nucleic acids largely ignored the principle of the cyclic organisation of DNA. In this connection, we analyze the principle of cyclicity, which in its generality may well complement the concept of the atomic structure of matter. (from the history of physics)

  17. Training requirements for health physicists in the decontamination/decommissioning field

    International Nuclear Information System (INIS)

    Copenhaver, E.D.; Parzyck, D.C.

    1986-01-01

    While a significant decrease in the number of new facilities requiring health physics surveillance has occurred in the past decade, there has been a tremendous increase in the need for health physicists to fill regulatory requirements at existing facilities and the Decontamination and Decommissioning requirements of older facilities nearing the end of their operational lifetime. There is a continuing long-term need to provide trained health physicists with the special skills to meet these requirements. Decontamination and decommissioning programs require both basic and specialized health physics activities to be performed (1) to evaluate the radiation environment of the facility under consideration, (2) to establish the standards to which cleanup activities must be pursued, and (3) to adequately protect the personnel involved in the cleanup. Performance-based training, based on job task analysis, is an appropriate way to define the different types of health physics expertise required for D and D programs. Materials have been developed to describe potential job requirements in the radiation protection field, and the appropriate training goals to meet these requirements

  18. Compendium to radiation physics for medical physicists. 300 problems and solutions

    International Nuclear Information System (INIS)

    Podgorsak, Ervin B.

    2014-01-01

    Can be used in combination with other textbooks. Exercise book for graduate and undergraduate students of medical physics and engineering. Well chosen and didactically presented problems. Perfect set for learning in connection with the textbook by Podgorsak and others. Detailed derivation of results with many detailed illustrations. Fully worked-out solutions to exercises/questions. Combines exercises in radiation physics and medical physics. This exercise book contains 300 typical problems and exercises in modern physics and radiation physics with complete solutions, detailed equations and graphs. This textbook is linked directly with the textbook ''Radiation Physics for Medical Physicists'', Springer (2010) but can also be used in combination with other related textbooks. For ease of use, this textbook has exactly the same organizational layout (14 chapters, 128 sections) as the ''Radiation Physics for Medical Physicists'' textbook and each section is covered by at least one problem with solution given. Equations, figures and tables are cross-referenced between the two books. It is the only large compilation of textbook material and associated solved problems in medical physics, radiation physics, and biophysics.

  19. Advances in the physics of radiation oncology - 50 years of contributions by US Medical Physicists

    International Nuclear Information System (INIS)

    Suntharalingam, N.

    2008-01-01

    Medical Physicists have a long standing record in the advancement of the discipline of Radiation Oncology, not only in the United States but world-wide, going back to the pre-world war II era. In the United States the contributions of Failla and Quimby, first at Memorial Hospital and then at Columbia University in New York, laid the foundation for the Profession of Medical Physics in the US. Radiation Therapy first used low and high kilovoltage machines for external beam therapy. Radium (Parker) and radon seeds (Quimby) were used for brachytherapy. Subsequently, clinical Van-de-Graaff machines (Trump and Wright) and the Betatron (Kerst, Adams and Skaggs) provided the required photon beams and also made available clinically useful electron beams. The work of John Laughlin, Larry Lanzl, Jacques Ovadia together with Gail Adams and Lester Skaggs, needs to be recognized for their pioneering efforts. With the introduction of Cobalt-60 Teletherapy (Harold Johns and the Canadian Group, Gilbert Fletcher and the MD Anderson Group) and Linear Accelerators (Henry Kaplan and the Stanford Group, and Varian), in the late 1950s ∼ 1960, there was even a greater need for the strong participation of medical physicists, as a useful technical resource to the physicians

  20. The global survey of physicists: A collaborative effort illuminates the situation of women in physics

    Science.gov (United States)

    Ivie, Rachel; Tesfaye, Casey Langer; Czujko, Roman; Chu, Raymond

    2013-03-01

    The results of the Global Survey of Physicists draw attention to the need to focus on factors other than representation when discussing the situation of women in physics. Previous studies of women in physics have mostly focused on the lack of women in the field. This study goes beyond the obvious shortage of women and shows that there are much deeper issues. For the first time, a multinational study was conducted with approximately 15,000 respondents from 130 countries, showing that problems for women in physics transcend national borders. Across all countries, women have fewer resources and opportunities and are more affected by cultural expectations concerning child care. We show that limited resources and opportunities hurt career progress, and because women have fewer opportunities and resources, their careers progress more slowly. We also show the disproportionate effects of children on women physicists' careers. Cultural expectations about home and family are difficult to change. However, for women to have successful outcomes and advance in physics, they must have equal access to resources and opportunities.