WorldWideScience

Sample records for polar research secretariat

  1. International Scientific Cooperation of Research Groups in Executive Secretariat of Brazil

    Directory of Open Access Journals (Sweden)

    Fernanda Cristina Sanches

    2017-01-01

    Full Text Available Scientific cooperation in international scope has been significantly intensified in recent years, as it strengthens the courses of graduation and graduate programs, corroborates to increase the number and quality of research, assists in granting scholarships and enables resource sharing, among others. So, given the importance of this theme, this study has the following objective: to examine how it has developed international scientific cooperation of the members of research groups in the Executive Secretariat in Brazil. To this end, a study of quantitative and qualitative nature was developed, from the descriptive method. The data used have secondary origin because they were obtained on the basis of consultation with the Lattes curriculum of all members of research groups of the Executive Secretariat area, from search by the following terms: Secretariat; Secretariat executive and secretarial. The main results show that all groups to a greater or lesser number have presented scientific productions of this nature. Among the types of production, the groups present greater international collaboration in the indicator "publications" and with countries, Portugal and Argentina, respectively.

  2. PHITS code improvements by Regulatory Standard and Research Department Secretariat of Nuclear Regulation Authority

    International Nuclear Information System (INIS)

    Goko, Shinji

    2017-01-01

    As for the safety analysis to be carried out when a nuclear power company applies for installation permission of facility or equipment, business license, design approval etc., the Regulatory Standard and Research Department Secretariat of Nuclear Regulation Authority continuously conducts safety research for the introduction of various technologies and their improvement in order to evaluate the adequacy of this safety analysis. In the field of the shielding analysis of nuclear fuel transportation materials, this group improved the code to make PHITS applicable to this field, and has been promoting the improvement as a tool used for regulations since FY2013. This paper introduced the history and progress of this safety research. PHITS 2.88, which is the latest version as of November 2016, was equipped with the automatic generation function of variance reduction parameters [T-WWG] etc., and developed as the tool equipped with many effective functions in practical application to nuclear power regulations. In addition, this group conducted the verification analysis against nuclear fuel packages, which showed a good agreement with the analysis by MCNP, which is extensively used worldwide and abundant in actual results. It also shows a relatively good agreement with the measured values, when considering differences in analysis and measurement. (A.O.)

  3. Polar Biomedical Research - An Assessment.

    Science.gov (United States)

    1982-10-01

    to grow more crops in subpolar Alaska. The severity of the polar conditions in Antarctica allow no practical method for providing volumes of plant food...for an expanded population. Any experiments in polar regions in food production involving geothermal heat, solar energy, hydroponics , or aquaculture

  4. Polarized neutrons for Australian scientific research

    International Nuclear Information System (INIS)

    Kennedy, Shane J.

    2005-01-01

    Polarized neutron scattering has been a feature at ANSTO's HIFAR research reactor since the first polarization analysis (PA) spectrometer Longpol began operation over 30 years ago. Since that time, we have improved performance of Longpol and added new capabilities in several reincarnations of the instrument. Most of the polarized neutron experiments have been in the fields of magnetism and superconductivity, and most of that research has involved PA. Now as we plan our next generation neutron beam facility, at the Replacement Research Reactor (RRR), we intend to continue the tradition of PA but with a far broader scope in mind. Our new capabilities will combine PA and energy analysis with both cold and thermal neutron source spectra. We will also provide capabilities for research with polarized neutrons in small-angle neutron scattering and in neutron reflectometry. The discussion includes a brief historical account of the technical developments with a summary of past and present applications of polarized neutrons at HIFAR, and an outline of the polarized neutron capabilities that will be included in the first suite of instruments, which will begin operation at the new reactor in 2006

  5. Virtually Shaping the Future of Polar Research

    Science.gov (United States)

    Baeseman, J. L.; Koldunov, N. V.; Jochum, K.

    2009-12-01

    The Association of Polar Early Career Scientists (APECS) is an international and interdisciplinary organization for undergraduate and graduate students, postdoctoral researchers, early faculty members, educators and others with interests in Polar Regions and the wider cryosphere that started as a result of the International Polar Year (IPY). APECS is leading the way for virtual communication of polar research through several activities: an online Polar Literature Discussion Forum, a Virtual Poster Session, and Communication beyond the conference setting. APECS has created an extensive online discussion forum where researchers share both classic and cutting-edge literature articles and critique techniques that were used by authors, helping to improve methods as well as discover new ways to approach polar research questions. Many researchers present their results as posters at conferences. APECS has taken this process to a new level by creating a format to display previously presented posters online instead of these files simply sitting on a researcher’s hard-drive. Not only are the posters online, a monthly conference call open to hundreds of participants allows researchers to share their work with a new audience - fellow researchers, community members, potential colleagues, policy makers and educators. These calls are recorded and archived online so the next time someone visits the poster, they can hear the researcher describe their work and communicate with the researcher questions they may have, potential ways to collaborate or share different methodologies to improve future endeavors. Peer-reviewed literature articles are the currency of science and APECS has capitalized on this by creating a way for researchers to increase the exposure of their publications beyond the table of contents published by journals. The Polar Literature Discussion Forum is a new way for researchers to share their papers, as well as discuss classic articles. This has become a popular

  6. The Polar Rock Repository: Rescuing Polar Collections for New Research

    Science.gov (United States)

    Grunow, A.

    2016-12-01

    Geological field expeditions in polar regions are logistically difficult, financially expensive and can have a significant environmental impact on pristine regions. The scarcity of outcrop in Antarctica (98% ice-covered) makes previously collected rock samples very valuable to the science community. NSF recognized the need for preserving rock, dredge, and terrestrial core samples from polar areas and created the Polar Rock Repository (PRR). The PRR collection allows for full and open access to both samples and metadata via the PRR website. In addition to the physical samples and their basic metadata, the PRR archives supporting materials from the collector, field notebooks, images of the samples, field maps, air photos, thin sections and any associated bibliography/DOI's. Many of these supporting materials are unique. More than 40,000 samples are available from the PRR for scientific analysis to researchers around the globe. Most of the samples cataloged at the PRR were collected more than 30 years ago, some more than 100 years ago. The rock samples and metadata are made available online through an advanced search engine for the PRR website. This allows scientists to "drill down" into search results using categories and look-up object fields similar to websites like Amazon. Results can be viewed in a table, downloaded as a spreadsheet, or plotted on an interactive map that supports display of satellite imagery and bathymetry layers. Samples can be requested by placing them in the `shopping cart'. These old sample collections have been repeatedly used by scientists from around the world. One data request involved locating coal deposits in Antarctica for a global compilation and another for looking at the redox state of batholithic rocks from the Antarctic Peninsula using magnetic susceptibilities of PRR rocks. Sample usage has also included non-traditional geologic studies, such as a search for monopoles in Cenozoic volcanic samples, and remote sensing

  7. Training the New Generation of Polar Researchers

    Science.gov (United States)

    Drobot, S.; Weiler, C. S.

    2008-12-01

    The polar regions are changing rapidly, and many of the pressing problems faced in the future will require a new generation of polar researchers to be disciplinary experts and work across traditional disciplinary boundaries to conduct socially relevant, transformative research, and translate it to more effective action. To learn about the past and better address these new challenges, a select international group of 35 students and early career researchers who are conducting research during the 2007-2009 International Polar Year were brought together May 4-11, 2008, at the La Foret Conference Center for the New Generation Polar Research (NGPR) Symposium. The participants were drawn from professional backgrounds spanning the spectrum of social, natural, and physical sciences and represented the research programs of 7 countries. In addition to the participants, 12 mentors, some of whom participated in the IGY, shared insights, stories, and expertise. This diverse and ambitious group spent an intensive week learning about many important aspects of IPY history and research, along with communication, outreach, interdisciplinary research and career development. Each of the participants presented a 7-minute overview of his or her IPY research and provided details and discussion in evening poster sessions. Polar history provided an informative and unifying context for discussions of the past, present, and future that lasted throughout the week. Mentors and guest speakers shared insights and advice on media interactions, and many participants were subsequently interviewed for an upcoming radio story to be aired on National Public Radio. Several presentations on outreach were followed by a hands-on session for a group 1st grade students who were visiting the La Foret Conference Center. The Symposium also featured several break-out sessions, where small groups of participants and mentors discussed challenges related to interdisciplinary research, science advocacy, and

  8. PolarTREC-Teachers and Researchers Exploring and Collaborating: Bringing Polar Research to the Classroom

    Science.gov (United States)

    Warnick, W. K.; Warburton, J.; Breen, K.; Wiggins, H. V.; Larson, A.; Behr, S.

    2006-12-01

    PolarTREC-Teachers and Researchers Exploring and Collaborating is a three-year (2007-2009) teacher professional development program that pairs K-12 teachers with researchers to improve science education through authentic polar research experience. PolarTREC builds on the strengths of the existing TREC program in the Arctic, an NSF supported program managed by the Arctic Research Consortium of the US (ARCUS), to embrace a wider range of research activities in the Arctic and Antarctic. PolarTREC uses a Teacher Research Experience (TRE) model to foster the integration of research and education to produce a legacy of long-term teacher-researcher collaborations, improved teacher content knowledge through experiences in scientific inquiry, and broad public interest and engagement in polar science. PolarTREC will enable thirty-six teachers to spend two to six weeks in the Arctic or Antarctic, working closely with researchers investigating a wide range of topics such as sea-ice dynamics, terrestrial ecology, marine biology, atmospheric chemistry, and long-term climate change. With the help of their host researcher and the research team, teachers will develop the experience and tools necessary to teach science through scientific inquiry and investigation based on real-world experiences. While in the field, teachers and researchers will communicate extensively with their colleagues, communities, and hundreds of students of all ages across the globe, using a variety of tools including satellite phones, online journals, podcasts and interactive "Live from IPY" calls and web-based seminars. The online outreach elements of the project convey these experiences to a broad audience far beyond the classrooms of the PolarTREC teachers. In addition to field research experiences, PolarTREC will support teacher professional development and a sustained community of teachers, scientists, and the public through workshops, Internet seminars, an e-mail listserve, and ongoing teacher/researcher

  9. Research on generating various polarization-modes in polarized illumination system

    Science.gov (United States)

    Huang, Jinping; Lin, Wumei; Fan, Zhenjie

    2013-08-01

    With the increase of the numerical aperture (NA), the polarization of light affects the imaging quality of projection lens more significantly. On the contrary, according to the mask pattern, the resolution of projection lens can be improved by using the polarized illumination. That is to say, using the corresponding polarized beam (or polarization-mode) along with the off-axis illumination will improve the resolution and the imaging quality of the of projection lens. Therefore, the research on the generation of various polarization modes and its conversion methods become more and more important. In order to realize various polarization modes in polarized illumination system, after read a lot of references, we provide a way that fitting for the illumination system with the wavelength of 193nm.Six polarization-modes and a depolarized mode are probably considered. Wave-plate stack is used to generate linearly polarization-mode, which have a higher degree polarization. In order to generate X-Y and Y-X polarization mode, the equipment consisting of four sectors of λ/2 wave plate was used. We combined 16 sectors of λ/2 wave plate which have different orientations of the "slow" axis to generate radial and azimuthal polarization. Finally, a multi-polarization control device was designed. Using the kind of multi-polarization control device which applying this method could help to choose the polarization modes conveniently and flexibility for the illumination system.

  10. EXECUTIVE SECRETARIAT STUDENTS´ PROFILE (FRESHMEN AND SENIORS: A COMPARATIVE STYDY IN PUBLIC EDUCATION INSTITUTIONS

    Directory of Open Access Journals (Sweden)

    Vania Souza Bilert

    2012-05-01

    Full Text Available The objective of this paper is to identify the profile of beginner and graduate students who apply for Executive Secretariat graduation course. This research was carried out with students from 11 Brazilian public undergraduate schools, both federal and state ones. This is considered a descriptive and exploratory study, which analyzed 507 students, 311 beginners and 196 graduate ones. The main results show that students perform in different segment companies, but especially in service companies, 87% are female and the predominant age group is between 17 and 24 years old. In a positive way, this research stands out the factor that these students perform professionally since the beginning of the graduation, exerting the functions which are up to the Executive Secretariat professional. This reveals that the students are able to link what they have learned inside the classroom with the professional practice, which also highlights the acceptance of professionals of Executive Secretariat by the entrepreneurship.

  11. Individuality and Leadership Reflected in Randall Wallace's Secretariat

    OpenAIRE

    Primadany, Risma Sinta

    2017-01-01

    Secretariat is a movie which tells about the life of Penny Chenery in leading her Meadow Stable. Secretariat is the name of a horse owned by Chenery's family who can bring the business into success by winning many race competitions. The main character, Penny Chenery, is the person who continues leading her parent's business. The aims of this thesis are to describe the intrinsic aspects which are narrative elements (characters, setting, conflict) and cinematic elements (camera distance, angle,...

  12. Factors Affecting The Career Development Of Employees In Secretariat Office Of City Samarinda

    Directory of Open Access Journals (Sweden)

    Santi Rande

    2015-03-01

    Full Text Available ABSTRACT Although the primary responsibility for career planning lies in the individual but organizational career planning should be completely in line with individual career planning if an organization wants to retain the best employees. Assumptions and the perspective delivers the researchers to examine the influence of aspects of individual and organizational aspects of the career development of employees within the organization of government. The population in this study were employees of the Regional Secretariat of Samarinda by sampling using Proportional Sampling. This research uses a quantitative approach to the explanation that the format is done through surveys. The results showed that the main factors affecting the career development of staff at the Regional Secretariat Samarinda is a factor of career counseling performance appraisal and career mapping which affects the employees career development is partially respectively or simultaneously together .

  13. Connecting polar research to NGSS STEM classroom lessons

    Science.gov (United States)

    Brinker, R.; Kast, D.

    2016-12-01

    Next Generation Science Standards (NGSS) are designed to bring consistent, rigorous science teaching across the United States. Topics are categorized as Performance Expectations (PE), Disciplinary Core Ideas (DCI), Cross-Cutting Concepts (CCC), and Science and Engineering Practices (SEP). NGSS includes a focus on environmental science and climate change across grade levels. Earth and planetary sciences are required at the high school level. Integrating polar science lessons into NGSS classrooms brings relevant, rigorous climate change curriculum across grade levels. Polar science provides opportunities for students to use current data during lessons, conduct their own field work, and collaborate with scientists. Polar science provides a framework of learning that is novel to most students. Inquiry and engagement are high with polar science lessons. Phenomenon related to polar science provide an excellent tool for science teachers to use to engage students in a lesson, stimulate inquiry, and promote critical thinking. When taught effectively, students see the connections between their community, polar regions and climate change, regardless of where on the planet students live. This presentation describes examples of how to effectively implement NGSS lessons by incorporating polar science lessons and field research. Examples of introductory phenomenon and aligned PEs, CCCs, DCIs, and SEPs are given. Suggested student activities, assessments, examples of student work, student research, labs, and PolarTREC fieldwork, use of current science data, and connections to scientists in the field are provided. The goals of the presentation are to give teachers a blueprint to follow when implementing NGSS lessons, and give scientists an understanding of the basics of NGSS so they may be better able to relate their work to U.S. science education and be more effective communicators of their science findings.

  14. Research progress on polar lipids of deinococcus radiodurans

    International Nuclear Information System (INIS)

    Feng Qiong; Tian Bing; Hua Yuejin

    2013-01-01

    Deinococcus radiodurans is extremely resistant to radiation, desiccation, oxidizing agents and other extreme conditions. One of the unique lipids in Deinococcus radiodurans is the polar lipid phosphoglycolipid with alkylamine as the main component. Alkylamine derived from fatty acids. The composition characteristic of lipids is one of the classification criterias of Deinococcus. This article provided an overview of the main features of the Deinococcus radiodurans and introduced special polar lipids that have been found as well as the taxonomy significances of such lipids. The research progress of the relationship between lipids and their resistance mechanisms and the prospects of special lipids in Deinococcus radidurans have also been discussed. (authors)

  15. Climate Comics: polar research in a cartoon form

    Science.gov (United States)

    Courville, Z.; Carbaugh, S.; Defrancis, G.; Donegan, R.; Brown, C.; Perovich, D. K.; Richter-Menge, J.

    2013-12-01

    Climate Comics is a collaborative outreach effort between the Montshire Museum of Science, in Norwich, VT, the Cold Regions Research and Engineering Laboratory (CRREL) research staff, and freelance artist and recent graduate of the Center for Cartoon Studies in White River Junction, VT, Sam Carbaugh. The project involves the cartoonist, the education staff from the museum, and researchers from CRREL creating a series of comic books with polar science and research themes, including sea ice monitoring, sea ice albedo, ice cores, extreme microbial activity, and stories and the process of fieldwork. The aim of the comic series is to provide meaningful science information in a comic-format that is both informative and fun, while highlighting current polar research work done at the lab. The education staff at the Montshire Museum develops and provides a series of hands-on, inquiry-based activity descriptions to complement each comic book, and CRREL researchers provide science background information and reiterative feedback about the comic books as they are being developed. Here, we present the motivation for using the comic-book medium to present polar research topics, the process involved in creating the comics, some unique features of the series, and the finished comic books themselves. Cartoon illustrating ways snow pack can be used to determine past climate information.

  16. Polar Research Board annual report, 1987 and future plans

    Energy Technology Data Exchange (ETDEWEB)

    1988-01-01

    This annual report describes the Polar Research Board, its origin and objectives, its work and plans, and its principle activities and accomplishments during calendar year 1987. The Overview presents a concise summary of the various aspects of the Board's program and of its responsibilities as US National Committee for the Scientific Committee on Antarctic Research (SCAR) of the International Council of Scientific Unins. Arctic and Antarctic activities are described.

  17. Polar Research Board annual report, 1987 and future plans

    Energy Technology Data Exchange (ETDEWEB)

    1988-12-31

    This annual report describes the Polar Research Board, its origin and objectives, its work and plans, and its principle activities and accomplishments during calendar year 1987. The Overview presents a concise summary of the various aspects of the Board`s program and of its responsibilities as US National Committee for the Scientific Committee on Antarctic Research (SCAR) of the International Council of Scientific Unins. Arctic and Antarctic activities are described.

  18. Archive of information about geological samples available for research from the Ohio State University Byrd Polar and Climate Research Center (BPCRC) Polar Rock Repository

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Polar Rock Repository (PRR) operated by the Byrd Polar and Climate Research Center (BPCRC) at the Ohio State University is a partner in the Index to Marine and...

  19. United States Naval Academy Polar Science Program; Undergraduate Research and Outreach in Polar Environments

    Science.gov (United States)

    Woods, J. E.

    2013-12-01

    The United States Naval Academy (USNA) Polar Science Program (PSP), has been very active completing its own field campaign out of Barrow, AK, sent students to the South Pole, participated in STEM activities and educated over 100 future Naval Officers about the Polar Regions. Each activity is uniquely different, but has the similar undertone of sharing the recent rapid changes in the Cryosphere to a wide range of audiences. There is further room for development and growth through future field campaigns and new collaborations. The Naval Academy Ice Experiment (NAICEX) 2013 was based out of the old Naval Arctic Research Laboratory (NARL) in Barrow, AK. In joint collaboration with the University of Delaware, University of Washington, and Naval Research Laboratory we successfully took multiple measurements for over a week on the fast ice just offshore. Five undergraduate students from USNA, as well as 3 graduate students from University of Delaware participated, as well as multiple professors and instructors from each institution. Data collected during the experiment will be used in capstone courses and thesis research. There was also an outreach component to the experiment, where local students from Barrow H.S. have been assigned to the USNA ice observations project for their own high school course work. Local students will be analyzing data that will contribute into the larger research effort at USNA through coordinated remote efforts and participation in future field experiments. The USNA STEM office is one of the most robust in the entire country. The USNA PSP is active within this program by developing polar specific modules that are integrated varying length outreach opportunities from a few hours to week long camps. USNA PSP also engages in educator training that is held at the Naval Academy each summer. Through this program of educating the educators, the far reaching levels of awareness are multiplied exponentially. Also, the USNA Oceanography Department has

  20. List of documents received by the INDC Secretariat

    International Nuclear Information System (INIS)

    1991-01-01

    The Nuclear Data Section of the IAEA receives documents originated by or for the International Nuclear Data Committee (INDC) for distribution. This list includes all INDC documents received and distributed by the INDC Secretariat during the period March 1989 to June 1990. The list is produced directly from computer printout, into two groups: one ordered by accession number, and the other ordered by document number within each origin series. The document lists also in an appendix the titles of reports received as single copies for information

  1. The Organization Culture In The Public Service At The Regional Secretariat Of Samarinda City

    Directory of Open Access Journals (Sweden)

    Anwar

    2015-02-01

    Full Text Available Abstract The purpose of this research to analyzing the process of the management of internal integration in an effort to improve public services in the secretariat of the city .In the research results seen that there are culture of bubuhan familial in the management of internal integration in the secretariat of the city of samarinda through a the creation of a language together and conceptual categories in b the distribution of power and status c establishment norms closeness of a working relationship peers and d the application of the award and punishment. In addition to want to answer a desire as well as the need for public service excellence service unit to improve integrated permit handling UPT integrated permit handling services agency one gate BPPTSP capital city of samarinda . In the management of internal integration process in cultural organization that takes the conceptculture of bubuhan must be planned carefully and without prejudice to the rules of law applicable because if not handled wisely can be counter-productive with the vision and mission of Samarinda Government because it can cause a client patron relations which can actually inhibit the organization in achieving its vision and mission.

  2. The research of some polygraphic paper samples's polarization characteristics

    Science.gov (United States)

    Gavryliak, Mykhailo S.; Dobrovolskyi, Yuriy G.; Motrych, Artem V.; Arkhelyuk, Alexander D.

    2018-01-01

    Methods of investigation the polarization characteristics of certain types of polygraph paper were described. The most effective method for estimation of the characteristic features of optical heterogeneities of polygraph paper was proposed. The greatest sensitivity to the structural organization of optical heterogeneities of paper was observed for linearly polarized light beams with 90 degree polarization azimuth.

  3. Polar Seismic TETwalker: Integrating Engineering Teaching and Research

    Science.gov (United States)

    Gifford, C. M.; Ruiz, I.; Carmichael, B. L.; Wade, U. B.; Agah, A.

    2007-12-01

    Based on the TETwalker robot platform at NASA/Goddard Space Flight Center, the Center for Remote Sensing of Ice Sheets (CReSIS) has begun work on designing and modeling the integration of seismic surveying equipment into the TETwalker robot architecture for use in polar environments. Employing multiple Seismic TETwalker robots will allow gathering of polar seismic data in previously inaccessible or unexplored terrains, as well as help significantly reduce human involvement in such harsh environments. NASA's TETwalker mobile robot uses a unique form of mobility to topple across the surface and over obstacles. This robot therefore does not suffer the fate of other wheeled and tracked robots if tipped over. It is composed of extending struts and nodes, forming a tetrahedral shape which can be strategically adjusted to change the robot's center of gravity for toppling. Of the many platforms the TETwalker architecture can form, the 4-TETwalker robot (consisting of four ground nodes, a center payload node, and interconnecting struts) has been the focus of current research. The center node has been chosen as the geophone deployment medium, designed in such a way to allow geophone insertion using any face of the robot's structure. As the robot comes to rest at the deployment location, one of its faces will rest on the surface. No matter which side it is resting on, a geophone spike will be perpendicular to its face and an extending strut will be vertical for pushing the geophone into the ground. Lengthening and shortening struts allow the deployment node to precisely place the geophone into the ground, as well as vertically orient the geophones for proper data acquisition on non-flat surfaces. Power source integration has been investigated, incorporating possible combinations of solar, wind, and vibration power devices onboard the robot models for long-term survival in a polar environment. Designs have also been modeled for an alternate center node sensor package (e

  4. [Research on the Thermal Infrared Polarization Properties of Fresh Snow].

    Science.gov (United States)

    Wang, Ting-ting; Li, Zhao-liang; Tang, Bo-hui; Sun, Wei-qi; Zhao, Yun-sheng

    2015-07-01

    Snow can directly affect the surface energy balance and climate change and has a significant impact on human life and production. It is therefore of great significance to study the fresh snow emission spectroscopy properties by using the thermal infrared Polarization technique. This can provide a basis for quantitative thermal infrared remote sensing monitoring of snow as well as a deeper understanding of global warming and appropriate countermeasures. This paper focuses on the investigation of the thermal infrared polarization properties of the fresh snow. The results show that the thermal emissive polarization properties of fresh snow depend significantly on the wavelengths (channels) and view angles used to measure them. Four channels are considered in this study, their spectral response ranges are 8-14 microm for channel 1 (CH1), 11.5-12.5 microm for channel 2 (CH2), 10.3-11.5 microm for channel 3 (CH) and 8.2-9.2 microm for channel 4 (CH4). The snow polarized radiance (L) and its polarized brightness temperature (T) manifest as L(CH1) >L(CH3) > L(CH4) > L(CH2) and T(CH4) > T(CH1) > T(CH2) > TCH3, respectively, while the degree of polarization (P) manifests as P0 > P30 > P40 > P20 > P0 > P50 where the subscript of P denotes the view angle. The maximum of both L and T occurs at the view angle of 50 degree and polarization angle of 90 degree while their minimum appears at the view angle of 30 degree and polarization angle of 75 degree for each channel. In addition, the results show that: CH3 is more appropriate for better investigation of the emissive polarization properties of snow. Linear relationship is found between the fresh snow polarized T and the polarization angle with the coefficient of determination larger than 0.77 for all four channels. The polarized brightness temperature of the fresh snow is found to be increased about 0.003 K per polarization angle within 0-135 degree. The degree of polarization of snow is almost independent of the channels we

  5. Collusion in International Organizations: How States Benefit from the Authority of Secretariats

    NARCIS (Netherlands)

    Dijkstra, Hylke

    2017-01-01

    In the theoretical literature on the authority of international secretariats, academics often dichotomise between states and secretariats. Even when they account for the fact that states are often divided, they normally adopt a two-step approach: states first resolve their own differences before

  6. Transforming Polar Research with Google Glass Augmented Reality (Invited)

    Science.gov (United States)

    Ruthkoski, T.

    2013-12-01

    Augmented reality is a new technology with the potential to accelerate the advancement of science, particularly in geophysical research. Augmented reality is defined as a live, direct or indirect, view of a physical, real-world environment whose elements are augmented (or supplemented) by computer-generated sensory input such as sound, video, graphics or GPS data. When paired with advanced computing techniques on cloud resources, augmented reality has the potential to improve data collection techniques, visualizations, as well as in-situ analysis for many areas of research. Google is currently a pioneer of augmented reality technology and has released beta versions of their wearable computing device, Google Glass, to a select number of developers and beta testers. This community of 'Glass Explorers' is the vehicle from which Google shapes the future of their augmented reality device. Example applications of Google Glass in geophysical research range from use as a data gathering interface in harsh climates to an on-site visualization and analysis tool. Early participation in the shaping of the Google Glass device is an opportunity for researchers to tailor this new technology to their specific needs. The purpose of this presentation is to provide geophysical researchers with a hands-on first look at Google Glass and its potential as a scientific tool. Attendees will be given an overview of the technical specifications as well as a live demonstration of the device. Potential applications to geophysical research in polar regions will be the primary focus. The presentation will conclude with an open call to participate, during which attendees may indicate interest in developing projects that integrate Google Glass into their research. Application Mockup: Penguin Counter Google Glass Augmented Reality Device

  7. Polar Biomedical Research: An Assessment. Appendix. Polar Medicine - A Literature Review.

    Science.gov (United States)

    1982-10-01

    maneuvers rather than physiologic adaptation.8 5,150,151 m-- Pathologic Changes during Polar Life Life in the polar zones entails increased risks for diseases ...patient. Protein- calorie malnutrition (as in starvation,535 ,601 ,6 02 celiac sprue,6 03 or anorexia nervosa6 04 ) leads to decreased calorigenesis. In...determinations during hypothermia have not been establishedt thus the consequences of alterations of blood gases is unclear. There is same evidence, however

  8. 2011 Joint Science Education Project: Research Experience in Polar Science

    Science.gov (United States)

    Wilkening, J.; Ader, V.

    2011-12-01

    The Joint Science Education Project (JSEP), sponsored by the National Science Foundation, is a two-part program that brings together students and teachers from the United States, Greenland, and Denmark, for a unique cross-cultural, first-hand experience of the realities of polar science field research in Greenland. During JSEP, students experienced research being conducted on and near the Greenland ice sheet by attending researcher presentations, visiting NSF-funded field sites (including Summit and NEEM field stations, both located on the Greenland ice sheet), and designing and conducting research projects in international teams. The results of two of these projects will be highlighted. The atmospheric project investigated the differences in CO2, UVA, UVB, temperature, and albedo in different Arctic microenvironments, while also examining the interaction between the atmosphere and water present in the given environments. It was found that the carbon dioxide levels varied: glacial environments having the lowest levels, with an average concentration of 272.500 ppm, and non-vegetated, terrestrial environments having the highest, with an average concentration of 395.143 ppm. Following up on these results, it is planned to further investigate the interaction of the water and atmosphere, including water's role in the uptake of carbon dioxide. The ecology project investigated the occurrence of unusual large blooms of Nostoc cyanobacteria in Kangerlussuaq area lakes. The water chemistry of the lakes which contained the cyanobacteria and the lakes that did not were compared. The only noticeable difference was of the lakes' acidity, lakes containing the blooms had an average pH value of 8.58, whereas lakes without the blooms had an average pH value of 6.60. Further investigation of these results is needed to determine whether or not this was a cause or effect of the cyanobacteria blooms. As a next step, it is planned to attempt to grow the blooms to monitor their effects on

  9. Research status of large mode area single polarization active fiber

    Science.gov (United States)

    Xiao, Chun; Zhang, Ge; Yang, Bin-hua; Cheng, Wei-feng; Gu, Shao-yi

    2018-03-01

    As high power fiber laser used more and more widely, to increase the output power of fiber laser and beam quality improvement have become an important goal for the development of high power fiber lasers. The use of large mode fiber is the most direct and effective way to solve the nonlinear effect and fiber damage in the fiber laser power lifting process. In order to reduce the effect of polarization of the fiber laser system, the study found that when introduces a birefringence in the single-mode fiber, the polarization state changes caused by the birefringence is far greater than the random polarization state changes, then the external disturbance is completely submerged, finally the polarization can be controlled and stabilized. Through the fine design of the fiber structure, if the birefringence is high enough to achieve the separation of the two polarization states, the fiber will have a different cut-off mechanism to eliminate polarization which is not need, which will realize single mode single polarization transmission in a band. In this paper, different types of single polarization fiber design are presented and the application of these fibers are also discussed.

  10. Scientific Research in Polar Seas – ERICON Science Perspective 2015-2030

    NARCIS (Netherlands)

    Wilmott, V.; Azzolini, R.; von Brandt, A.; Brinkhuis, H.; Camerlenghi, A.; Coakley, B.; De Santis, L.; Kristoffersen, Y.; Lembke-Jene, L.; Rebesco, M.; Thiede, J.; and other contributors, .

    2012-01-01

    Polar sciences are a modern branch of the natural sciences involving large groups of researchers, and sophisticated instrumentation contributing indispensable data for a better understanding of the polar regions and their impact on the global environment. The fact that a lot of the necessary

  11. Tracer-tracer relations as a tool for research on polar ozone loss

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Rolf

    2010-07-01

    The report includes the following chapters: (1) Introduction: ozone in the atmosphere, anthropogenic influence on the ozone layer, polar stratospheric ozone loss; (2) Tracer-tracer relations in the stratosphere: tracer-tracer relations as a tool in atmospheric research; impact of cosmic-ray-induced heterogeneous chemistry on polar ozone; (3) quantifying polar ozone loss from ozone-tracer relations: principles of tracer-tracer correlation techniques; reference ozone-tracer relations in the early polar vortex; impact of mixing on ozone-tracer relations in the polar vortex; impact of mesospheric intrusions on ozone-tracer relations in the stratospheric polar vortex calculation of chemical ozone loss in the arctic in March 2003 based on ILAS-II measurements; (4) epilogue.

  12. PolarTREC-Celebrating the Legacy of the IPY Through Researcher-Educator Partnerships

    Science.gov (United States)

    Timm, K.; Warburton, J.; Larson, A. M.

    2009-12-01

    Polar TREC-Teachers and Researchers Exploring and Collaborating, a three-year (2007-2009) NSF-funded program, has matched over 40 teachers with polar researchers working in multiple scientific disciplines for 2-8 week Teacher Research Experiences (TRE) in the Arctic and Antarctica during the IPY. PolarTREC contributes to the legacy of the IPY through the creation and dissemination of polar education resources, prolonged teacher-researcher relationships, and contributions to scholarly knowledge on the impacts of TRE's. Products developed during PolarTREC are helping to sustain the widespread interest and enthusiasm in the polar regions generated during the IPY. During their expeditions, participating teachers brought science and information about profound changes at the poles to school, community, and professional audiences through web-based communications, journals, discussion forums, multimedia, and live events. PolarTREC teachers constructed nearly 100 classroom lesson plans and activities as products of their experiences. Live events from the field attracted over 11,000 participants, primarily K-12 students. Although the field experience is central to the PolarTREC TRE Model, many participants cite the relationship they built with their teacher/researcher as one of the best outcomes. Through personal communications, presentations at professional conferences, and continued support of each other’s work through classroom visits or joint proposal development, teachers and researchers have maintained the mutually beneficial relationships established during the IPY. Participating scientists gained access to professional educators with expertise in translating research approaches and results into programs. The need for researchers to explain their research and “boil it down to the raw essence” helped many see how their work fits into a bigger picture, often helping them communicate outside their scientific discipline and to diverse public audiences. Teachers, on

  13. [Decision-making process and administrative practice: managing the State Health Secretariat in Bahia, Brazil].

    Science.gov (United States)

    Coelho, Thereza Christina Bahia; Paim, Jairnilson Silva

    2005-01-01

    This case study is based on research performed by the Bahia State Health Secretariat (SESAB), aimed at analyzing management practices during the implementation of a State government administrative reform. The institutional agenda shows evidence of limited participation by civil society and technical and operational staff in problem selection and prioritization, resulting from a work process pressured by high-level executive government staff. Decisions regarding "output" (projects, services, and activities) were made under the responsibility of subordinate operational levels and did not appear as issues in the institutional routine. Concerns related to "input" (financial and human resources) consumed most of the high-level efforts, with internal and external negotiations and compromises to assure access to them. Meanwhile the possible "outcome", namely public health status, represents the "occult subject" of the institutional discourse. Information emerges in institutional disputes as a technical "power resource" in its medical, epidemiological, health, and administrative dimensions. The issue of government "representation" and allied interests is based on ideological dispositions and authoritarian practices, thus contradicting the need for management transparency and modernization.

  14. Table of content translations of Soviet reports received by the INDC Secretariat

    International Nuclear Information System (INIS)

    1982-07-01

    The INDC Secretariat receives a number of Soviet reports in Russian as part of the INDC document distribution system. Because of their large number and size most of them cannot be translated by the IAEA. The ''Nuclear Physics Research in the USSR - Collected Abstracts'' report series and occasional reports of interest to the nuclear data community are translated by the IAEA on a regular basis, and are normally given a ''U'' distribution. The ''Table of Content Translations'' contain the translation of the table of contents (and abstracts when available) of those Soviet reports which the IAEA does not translate in full. The originals of these reports are normally available in limited quantities only and are given an INDC ''G'' distribution. This issue contains the table of content translation of the following reports: Nuclear Constants, volume 3(42), original distributed as INDC(CCP)-173/G; Nuclear Constants, volume 4(43), original distributed as INDC(CCP)-175/G; Nuclear Constants, volume 5(44); original distributed as INDC(CCP)-176/G

  15. New materials research for high spin polarized current

    International Nuclear Information System (INIS)

    Tezuka, Nobuki

    2012-01-01

    The author reports here a thorough investigation of structural and magnetic properties of Co 2 FeAl 0.5 Si 0.5 Heusler alloy films, and the tunnel magnetoresistance effect for junctions with Co 2 FeAl 0.5 Si 0.5 electrodes, spin injection into GaAs semiconductor from Co 2 FeAl 0.5 Si 0.5 , and spin filtering phenomena for junctions with CoFe 2 O 4 ferrite barrier. It was observed that tunnel magnetoresistance ratio up to 832%(386%) at 9 K (room temperature), which corresponds to the tunnel spin polarization of 0.90 (0.81) for the junctions using Co 2 FeAl 0.5 Si 0.5 Heusler electrodes by optimizing the fabrication condition. It was also found that the tunnel magnetoresistance ratio are almost the same between the junctions with Co 2 FeAl 0.5 Si 0.5 Heusler electrodes on Cr buffered (1 0 0) and (1 1 0) MgO substrates, which indicates that tunnel spin polarization of Co 2 FeAl 0.5 Si 0.5 for these two direction are almost the same. The next part of this paper is a spin filtering effect using a Co ferrite. The spin filtering effect was observed through a thin Co-ferrite barrier. The inverse type tunnel magnetoresistance ratio of −124% measured at 10 K was obtained. The inverse type magnetoresistance suggests the negative spin polarization of Co-ferrite barrier. The magnetoresistance ratio of −124% corresponds to the spin polarization of −0.77 by the Co-ferrite barrier. The last part is devoted to the spin injection from Co 2 FeAl 0.5 Si 0.5 into GaAs. The spin injection signal was clearly obtained by three terminal Hanle measurement. The spin relaxation time was estimated to be 380 ps measured at 5 K.

  16. Research on polarization noise of hollow-core photonic crystal fiber resonator optic gyroscope

    Science.gov (United States)

    Feng, Lishuang; Jiao, Hongchen; Song, Wenshuai

    2015-10-01

    Hollow-core photonic crystal fiber (HCPCF) resonator optic gyroscope is an important direction of high accuracy fiber optic gyroscope. The development and application of HCPCF has provided broad prospect for the research of resonator fiber optic gyroscope (RFOG). The HCPCF can restrict light to propagate in the fiber core filled with air/vacuum based on photonic band-gap effect. Compared with conventional polarization maintaining fiber based RFOG (PM-RFOG), the HCPCF based RFOG (HC-RFOG) has great potential to achieve lower nonreciprocal bias and better environment adaptability. The polarization noise, which is one of the main noise sources in the RFOG, is modeled and simulated in this paper. The resonance curves of RFOG with two polarization modes excited are presented, and the polarization noises caused by fiber parameters are calculated. The comparison of polarization noises between HCPCF resonator and polarization maintaining optical fiber (PMF) resonator are carried out by numerical simulation. The polarization features of the HCPCF resonator and conventional PMF resonator are experimentally characterized. The analysis result shows that the polarization stability of HCPCF resonator can be two orders of magnitude lower than that of the conventional PMF resonator. Therefore, the HCPCF resonator has evidently superiority in reducing polarization noise and improving gyro performance. The captive tests based on the HCPCF RFOG system are realized, and a bias stability in the range of 2.5°/s is successfully demonstrated.

  17. Breaking the Ice: Strategies for Future European Research in the Polar Oceans - The AURORA BOREALIS Concept

    Science.gov (United States)

    Lembke-Jene, L.; Biebow, N.; Wolff-Boenisch, B.; Thiede, J.; European Research Icebreaker Consortium

    2011-12-01

    Research vessels dedicated to work in polar ice-covered waters have only rarely been built. Their history began with Fritjof Nansen's FRAM, which he used for his famous first crossing of the Arctic Ocean 1893-1896. She served as example for the first generation of polar research vessels, at their time being modern instruments planned with foresight. Ice breaker technology has developed substantially since then. However, it took almost 80 years until this technical advance also reached polar research, when the Russian AKADEMIK FEDEROV, the German POLARSTERN, the Swedish ODEN and the USCG Cutter HEALY were built. All of these house modern laboratories, are ice-breakers capable to move into the deep-Arctic during the summer time and represent the second generation of dedicated polar research vessels. Still, the increasing demand in polar marine research capacities by societies that call for action to better understand climate change, especially in the high latitudes is not matched by adequate facilities and resources. Today, no icebreaker platform exists that is permanently available to the international science community for year-round expeditions into the central Arctic Ocean or heavily ice-infested waters of the polar Southern Ocean around Antarctica. The AURORA BOREALIS concept plans for a heavy research icebreaker, which will enable polar scientists around the world to launch international research expeditions into the central Arctic Ocean and the Antarctic continental shelf seas autonomously during all seasons of the year. The European Research Icebreaker Consortium - AURORA BOREALIS (ERICON-AB) was established in 2008 to plan the scientific, governance, financial, and legal frameworks needed for the construction and operation of this first multi-nationally owned and operated research icebreaker and polar scientific drilling platform. By collaborating together and sharing common infrastructures it is envisioned that European nations make a major contribution to

  18. How International was the Secretariat of the League of Nations?

    DEFF Research Database (Denmark)

    Dykmann, Klaas

    2015-01-01

    In recent years, scholars have contested conventional narratives such as that the League of Nations was a complete ‘failure’ or that the United Nations was a novelty in comparison with the League. Scholars now offer more nuanced and archive-based analyses. However, while traditional research has ...

  19. Dual-Polarization Observations of Precipitation: State of the Art in Operational and Research Applications

    Science.gov (United States)

    Chandra, C. V.; Moisseev, D. N.; Baldini, L.; Bechini, R.; Cremonini, R.; Wolff, D. B.; Petersen, W. A.; Junyent, F.; Chen, H.; Beauchamp, R.

    2016-12-01

    Dual-polarization weather radars have been widely used for rainfall measurement applications and studies of the microphysical characteristics of precipitation. Ground-based, dual-polarization radar systems form the cornerstones of national severe weather warning and forecasting infrastructure in many developed countries. As a result of the improved performance of dual-polarization radars for these applications, large scale dual-polarization upgrades are being planned for India and China. In addition to national forecast and warning operations, dual-polarization radars have also been used for satellite ground validation activities. The operational Dual-Polarization radars in the US are mostly S band systems whereas in Europe are mostly C band systems. In addition a third class of systems is emerging in urban regions where networks of X band systems are being deployed operationally. There are successful networks planned or already deployed in big cities such as Dallas Fort Worth, Tokyo or Beijing. These X band networks are developing their own operational domain. In summary a large infrastructure in terms of user specified products and dual use of operational research applications are also emerging in these systems. This paper will discuss some of the innovative uses of the operational dual-polarization radar networks for research purposes, with references to calibration, hydrometeor classification and quantitative precipitation estimation. Additional application to the study of precipitation processes will also be discussed.

  20. Improving Geoscience Education through the PolarTREC Teacher Research Experience Model (Invited)

    Science.gov (United States)

    Warburton, J.; Timm, K.; Larson, A. M.

    2010-12-01

    Teacher Research Experiences (TRE’s) are not new. For more than a decade, the National Science Foundation (NSF) as well as other federal agencies have been funding programs that place teachers with researchers in efforts to invigorate science education by bringing educators and researchers together through hands-on experiences. Many of the TRE’s are successful in providing a hands-on field experience for the teachers and researchers however many of the programs lack the resources to continue the collaborations and support the growing network of teachers that have had these field experiences. In 2007, NSF provided funding for PolarTREC—Teachers and Researchers Exploring and Collaborating, a program of the Arctic Research Consortium of the U.S. (ARCUS). PolarTREC is a TRE where K-12 teachers participate in polar field research, working closely with scientists as a pathway to improving science education. In just three years, it has become a successful TRE. What makes PolarTREC different than other the teacher research experience programs and how can others benefit from what we have learned? During this presentation, we will share data collected through the program evaluation and on how PolarTREC contributes to the discipline of Science, Technology, Engineering, and Mathematics (STEM) education and pedagogy through a model program conceived and organized according to current best practices, such as pre-research training, mentoring, support for classroom transfer, and long-term access to resources and support. Data shows that PolarTREC’s comprehensive program activities have many positive impacts on educators and their ability to teach science concepts and improve their teaching methods. Additionally, K-12 students polled in interest surveys showed significant changes in key areas including amount of time spent in school exploring research activities, importance of understanding science for future work, importance of understanding the polar regions as a person

  1. An Anatomy of Authority: The Bologna and ASEM Education Secretariats as Policy Actors and Region Builders

    Science.gov (United States)

    Dang, Que Anh

    2018-01-01

    This paper examines the sources of authority behind the Bologna and ASEM secretariats' technocratic appearance and administrative routines, and argues that they are transnational policy actors in their own right. By drawing on principal-agent theory and the concept of "authority," it offers an alternative framework for understanding the…

  2. 50 CFR 23.84 - What are the roles of the Secretariat and the committees?

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false What are the roles of the Secretariat and the committees? 23.84 Section 23.84 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE... ENDANGERED SPECIES OF WILD FAUNA AND FLORA (CITES) CITES Administration § 23.84 What are the roles of the...

  3. Decline and Fall:Why The South African Civilian Defence Secretariat ...

    African Journals Online (AJOL)

    After years of conflict, worsened by the demands of the Second World War and recommendations by several committees of enquiries and the Public Service Commission, the Secretariat was taken into the SADF, in a civilian capacity under the Comptroller. Between 1966 and 1968 it was absorbed into the various Staff ...

  4. The Evolvement of International Secretariats, Executive Heads and Leadership in Inter-Organizational Relations

    NARCIS (Netherlands)

    Reinalda, B.; Kille, K.J.; Koops, J.A.; Biermann, R.

    2017-01-01

    This chapter discusses inter-organizational relations (IORs) from the perspective of the international Secretariat of an International Governmental Organization (IGO) and the organization’s Executive Head. IORs are a long-standing phenomenon that resulted from the evolution of IGOs, the increase in

  5. A comparative study on Nutritional status of Preschool children in Kekirawa Divisional Secretariat area and Gampaha Divisional Secretariat area in Sri Lanka

    International Nuclear Information System (INIS)

    Perera, Kanattage Piumi Dananga Chamari; Weerasooriya, W.M.B.; Liyanage, Janitha A.

    2014-01-01

    Full text: Nutritional status is one of the most important indicators of the overall well being of population. According to Ayurveda Wellbeing of Physical, Mental & Spiritual status is known as health. This refers the definition of health defined by World Health Organization (WHO). Underweight, Stunting, Wasting and Overweight are important status of nutrition declared by the WHO. Height for age ≤ -2SD from the mean, Weight for height ≤ -2SD from the mean and Weight for age ≤ -2SD were defined as Stunting, Wasting and Underweight respectively. Results of a Survey carried out in 2007 in Sri Lanka were highlighted that, 21.1% are underweight, 14.7% were wasting and 17.3% were stunting among the under five year children. Under nutrition has been identified as a major problem among the preschool children in Sri Lanka. With this background, a preliminary survey was designed to identify the nutritional status of selected areas. Collecting Anthropometric measurements such as height & weight and evaluating the nutritional status of Preschool children were the objectives of the study. The study was carried out in the Kekirawa divisional secretariat division of the Anuradhapura district and Gampaha divisional secretariat division of the Gampaha district. Five preschools in Kekirawa division and two preschools in Gampaha division were randomly selected and 100 preschool children from each division were subjected to the survey. Under the permission of Preschool teachers, mothers of the Preschool children’s were instructed to meet Ayurveda Medical Officer in scheduled date with their children to take anthropometric measurements. Then heights and weight of children were measured using Stadiometer and scale with digital display. Recorded data were processed using WHO Anthro software - 2011. Age distribution of the sample was identified as 36-47 months and 48-60 months. Results of Prevalence of nutritional status revealed that 32.4% wasting, 24.5% stunting and 42

  6. European Medicines Agency, CAT Secretariat & US Food and Drug Administration.

    Science.gov (United States)

    2011-11-01

    The European Medicines Agency (EMA) and the Committee for Advanced Therapies (CAT) are responsible for reviewing applications for marketing authorization for Advanced Therapy Medicinal Products (ATMP), which include (stem) cell-based medicines, for the ATMP classification and certification procedure, and to provide scientific advice to developers of ATMPs. The CAT, an expert committee dedicated to ATMPs, was established by the Regulation (EC) No 1394/2007 on Advanced Therapies. The CAT came into operation in January 2009. ATMPs are defined in this Regulation as gene therapy and cell therapy medicinal products, and tissue-engineered products. The US FDA's Center for Biologics Evaluation and Research is responsible for ensuring the safety, purity, potency and effectiveness of many biologically derived products, including blood intended for transfusion, blood components and derivatives, vaccines and allergenic extracts, and cell, tissue and gene therapy products for the prevention, diagnosis and treatment of human diseases, conditions or injury. Human cells or tissue intended for implantation, transplantation, infusion or transfer into a human recipient are regulated as human cells, tissues, and cellular and tissue-based products (HCT/Ps).

  7. Establishing a definition of polar bear (Ursus maritimus) health: A guide to research and management activities

    Science.gov (United States)

    Patyk, Kelly A.; Duncan, Colleen G.; Nol, Pauline; Sonne, C.; Laidre, Kristin L.; Obbard, Martyn E.; Wiig, Øystein; Aars, Jon; Regehr, Eric V.; Gustafson, L.; Atwood, Todd C.

    2015-01-01

    The meaning of health for wildlife and perspectives on how to assess and measure health, are not well characterized. For wildlife at risk, such as some polar bear (Ursus maritimus) subpopulations, establishing comprehensive monitoring programs that include health status is an emerging need. Environmental changes, especially loss of sea ice habitat, have raised concern about polar bear health. Effective and consistent monitoring of polar bear health requires an unambiguous definition of health. We used the Delphi method of soliciting and interpreting expert knowledge to propose a working definition of polar bear health and to identify current concerns regarding health, challenges in measuring health, and important metrics for monitoring health. The expert opinion elicited through the exercise agreed that polar bear health is defined by characteristics and knowledge at the individual, population, and ecosystem level. The most important threats identified were in decreasing order: climate change, increased nutritional stress, chronic physiological stress, harvest management, increased exposure to contaminants, increased frequency of human interaction, diseases and parasites, and increased exposure to competitors. Fifteen metrics were identified to monitor polar bear health. Of these, indicators of body condition, disease and parasite exposure, contaminant exposure, and reproductive success were ranked as most important. We suggest that a cumulative effects approach to research and monitoring will improve the ability to assess the biological, ecological, and social determinants of polar bear health and provide measurable objectives for conservation goals and priorities and to evaluate progress.

  8. Establishing a definition of polar bear (Ursus maritimus) health: a guide to research and management activities.

    Science.gov (United States)

    Patyk, Kelly A; Duncan, Colleen; Nol, Pauline; Sonne, Christian; Laidre, Kristin; Obbard, Martyn; Wiig, Øystein; Aars, Jon; Regehr, Eric; Gustafson, Lori L; Atwood, Todd

    2015-05-01

    The meaning of health for wildlife and perspectives on how to assess and measure health, are not well characterized. For wildlife at risk, such as some polar bear (Ursus maritimus) subpopulations, establishing comprehensive monitoring programs that include health status is an emerging need. Environmental changes, especially loss of sea ice habitat, have raised concern about polar bear health. Effective and consistent monitoring of polar bear health requires an unambiguous definition of health. We used the Delphi method of soliciting and interpreting expert knowledge to propose a working definition of polar bear health and to identify current concerns regarding health, challenges in measuring health, and important metrics for monitoring health. The expert opinion elicited through the exercise agreed that polar bear health is defined by characteristics and knowledge at the individual, population, and ecosystem level. The most important threats identified were in decreasing order: climate change, increased nutritional stress, chronic physiological stress, harvest management, increased exposure to contaminants, increased frequency of human interaction, diseases and parasites, and increased exposure to competitors. Fifteen metrics were identified to monitor polar bear health. Of these, indicators of body condition, disease and parasite exposure, contaminant exposure, and reproductive success were ranked as most important. We suggest that a cumulative effects approach to research and monitoring will improve the ability to assess the biological, ecological, and social determinants of polar bear health and provide measurable objectives for conservation goals and priorities and to evaluate progress. Published by Elsevier B.V.

  9. Feasibility studies on future phycological research in polar regions

    Czech Academy of Sciences Publication Activity Database

    Elster, Josef; Svoboda, J.; Ohtani, S.; Kanda, H.

    2002-01-01

    Roč. 15, - (2002), s. 114-122 ISSN 0914-5613 R&D Projects: GA AV ČR IAA6005002; GA ČR GA206/93/1177 Institutional research plan: CEZ:AV0Z6005908; CEZ:MSM 123100004 Keywords : Cyanobacteria * algae * primary succession * primary production Subject RIV: EA - Cell Biology

  10. Annual report of the Certification Secretariat of Wind Turbines for 2010; AArsrapport: Energistyrelsens Godkendelsessekretariat for Vindmoeller 2010

    Energy Technology Data Exchange (ETDEWEB)

    Lemming, J.K.; Friis, P.

    2011-12-15

    This report was prepared as documentation for the activities in the Certification Secretariat of Wind Turbines in 2010. The secretariat has performed duties under a contract with the DEA, where the contents of the tasks are focused on administration of the Danish Certification Scheme for Wind Turbines. The report describes the current state of deployment of wind turbines in Denmark and the latest developments in wind turbine industry. Furthermore, the development of test areas is described. The tasks of the Secretariat has included daily administration, including ensuring the secretariat for the Advisory Committee, implementing the system of maintenance and service, development of new licensing rules for small wind turbines, and the approval and reviews of small wind turbines. In addition, the Secretariat and related experts from Risoe DTU participated in Danish and international standards committees. (Author)

  11. Polar Research with Unmanned Aircraft and Tethered Balloons

    Energy Technology Data Exchange (ETDEWEB)

    Ivey, M [Sandia National Laboratories; Petty, R [U.S. Department of Energy; Desilets, D [Sandia National Laboratories; Verlinde, J; Ellingson, R [Florida State University

    2014-01-24

    The Arctic is experiencing rapid climate change, with nearly double the rate of surface warming observed elsewhere on the planet. While various positive feedback mechanisms have been suggested, the reasons for Arctic amplification are not well understood, nor are the impacts to the global carbon cycle well quantified. Additionally, there are uncertainties associated with the complex interactions between Earth’s surface and the atmosphere. Elucidating the causes and consequences of Arctic warming is one of the many goals of the Climate and Environmental Sciences Division (CESD) of the U.S. Department of Energy’s (DOE) Biological and Environmental Research (BER) program, and is part of the larger CESD initiative to develop a robust predictive understanding of Earth’s climate system.

  12. Activities and Issues of a Developed Information System for the Italian Polar Research

    Directory of Open Access Journals (Sweden)

    A Damiani

    2010-02-01

    Full Text Available Activities performed to develop an information system for the diffusion of Italian polar research (SIRIA project are here described. The system collects and shares information related to research projects carried out in both the Antarctic (since 1985 and Arctic (since 1997 regions. It is addressed primarily to dedicated users in order to foster interdisciplinary research but non-specialists may also be interested in the major results. SIRIA is in charge of managing the National Antarctic Data Center of Italy and confers its metadata to the Antarctic Master Directory. Since 2003, the National Antarctic Research Program has funded this project, which, by restyling its tasks, databases, and web site, is becoming the portal of Italian polar research. Issues concerning data management and policy in Italy are also covered.

  13. POLAR-PALOOZA Polar Researchers and Arctic Residents Engage, Inform and Inspire Diverse Public Audiences by sharing Polar Science and Global Connections during the International Polar Year, using a New Model of Informal Science Education

    Science.gov (United States)

    Haines-Stiles, G.; Akuginow, E.

    2006-12-01

    (Please note that the POLAR-PALOOZA initiative described in this Abstract is-as of 9/7/2006-"pending" for possible support from NSF and NASA as part of this year's IPY solicitation. Subject to decisions expected by 9/30, this presentation would either be withdrawn, or amplified with specific participants, locations and dates.) Despite the success of well-regarded movies like "March of the Penguins", the polar regions remain a great unknown for most people. Public knowledge about the Arctic and Antarctic, and the critical role of the Poles in the entire Earth system, is nonexistent, incomplete or burdened with misperceptions. The International Polar Years of 2007-2009-and associated "I*Y" science years such as IHY, IYPE and eGY-present a unique opportunity to change this. The people who can best effect this change are those who know the Poles best, through living or working there. Based on innovative but proven models, POLAR-PALOOZA will use three complementary strategies to engage, inform and inspire large public audiences. (1) A national tour, under the working title "Stories from a Changing Planet", will include in-person presentations at science centers, museums, libraries and schools across North America, including Canada and Mexico. The presentations will be augmented by High Definition Video taped on location at the Poles, audio and video podcasts, and special education and outreach activities for targeted audiences. "Stories from a Changing Planet" will provide diverse audiences with an exciting opportunity to meet and interact directly with polar experts, and to appreciate why the Poles and the research done there are directly relevant to their lives. (2) The "HiDef Video Science Story Capture Corps" is a team of professional videographers, using the latest generation of low-cost, high-quality cameras, deployed to both Poles. They will document the work of multiple researchers and projects, rather than focusing on one topic for a single broadcast program

  14. Drilling Polar Oceans with the European Research Icebreaker AURORA BOREALIS: the IODP Context

    Science.gov (United States)

    Lembke-Jene, Lester; Wolff-Boenisch, Bonnie; Azzolini, Roberto; Thiede, Joern; Biebow, Nicole; Eldholm, Olav; Egerton, Paul

    2010-05-01

    Polar oceans are characterized by extreme environmental conditions for humans and materials, and have remained the least accessible regions to scientists of the IODP. DSDP and ODP have for long faced specific technical and logistical problems when attempting to drill in ice-covered polar deep-sea basins. The Arctic Ocean and large areas of the high-latitude Southern Ocean remained largely un-sampled by ODP and remain one of the major scientific and technological challenges for IODP. Drilling in these regions has been discussed and anticipated for decades and the scientific rationales are reflected in the science plans of the international Nansen Arctic Drilling Program (NAD) or the Arctic Program Planning Group (APPG) of ODP/IODP, amongst others. More recently, the rationale to investigate the polar oceans in a holistic approach has been outlined by workshops, leading to strategic assessments of the scientific potential and new drilling proposals. The European Polar Board took the initiative to develop a plan for a novel and dedicated research icebreaker with technical capabilities hitherto unrealised. This research icebreaker will enable autonomous operations in the central Arctic Ocean and the Southern Ocean, even during the severest ice conditions in the deep winter, serving all marine disciplines of polar research including scientific drilling: The European Research Icebreaker and Deep-Sea Drilling Vessel AURORA BOREALIS. AURORA BOREALIS is presently planned as a multi-purpose vessel. The ship can be deployed as a research icebreaker in all polar waters during any season of the year, as it shall meet the specifications of the highest ice-class attainable (IACS Polar Code 1) for icebreakers. During the times when it is not employed for drilling, it will operate as the most technically advanced multi-disciplinary research vessel in the Arctic or polar Southern Ocean. AURORA BOREALIS will be a "European scientific flagship facility" (fully open to non

  15. Long-distance delivery of multi-channel polarization signals in nuclear fusion research

    Science.gov (United States)

    Ko, Jinseok; Chung, Jinil; Lee, Kyuhang

    2017-04-01

    A polarization-preserving optical system that includes a dual photoelastic modulator (PEM) has been designed and fabricated for the motional Stark effect (MSE) diagnostic system which measures internal magnetic field structures inside the tokamak for the Korea Superconducting Tokamak Advanced Research. The collection optics located outside the vacuum window is composed of four lenses, a dielectric coated mirror, and a dichroic beam splitter in addition to the PEM and a polarizer. The fiber dissector is designed based on the focal plane that aligns 25 lines of sight, each of which constitutes a bundle of 19 600-μm fibers. The fibers run about 40 m from the front optics in the tokamak vacuum vessel to the detector in the diagnostic area remote from the tokamak hall. This takes the advantage of the fact that the polarization information is intensity-modulated once going through the PEM and the polarizer. The polarization signals measured by the MSE diagnostic successfully demonstrates its proof-of-principle physics that is critical in the stable and steady-state operation of the tokamak plasmas.

  16. ‘He used to give me Turkish lessons in Constantinople’: How to get a job in the League Secretariat

    DEFF Research Database (Denmark)

    Ikonomou, Haakon

    2017-01-01

    This blog looks at one specific road into international bureaucracy, to draw up some more general insights about the recruitment practices of the League: The overall argument being that while the recruitment practices of the Secretariat became increasingly institutionalized, professionalized...

  17. PolarTREC-Teachers and Researchers Exploring and Collaborating: Innovative Science Education from the Poles to the World

    Science.gov (United States)

    Warnick, W. K.; Warburton, J.; Breen, K.; Wiggins, H. V.; Larson, A.; Behr, S.

    2006-12-01

    PolarTREC-Teachers and Researchers Exploring and Collaborating is a three-year (2007-2009) teacher professional development program celebrating the International Polar Year (IPY) that will advance polar science education by bringing K-12 educators and polar researchers together in hands-on field experiences in the Arctic and Antarctic. PolarTREC builds on the strengths of the existing TREC program in the Arctic, an NSF supported program managed by the Arctic Research Consortium of the US (ARCUS), to embrace a wide range of activities occurring at both poles during and after IPY. PolarTREC will foster the integration of research and education to produce a legacy of long-term teacher-researcher collaborations, improved teacher content knowledge through experiences in scientific inquiry, and broad public interest and engagement in polar science and IPY. PolarTREC will enable thirty-six teachers to spend two to six weeks in the Arctic or Antarctic, working closely with researchers investigating a wide range of IPY science themed topics such as sea-ice dynamics, terrestrial ecology, marine biology, atmospheric chemistry, and long-term climate change. While in the field, teachers and researchers will communicate extensively with their colleagues, communities, and hundreds of students of all ages across the globe, using a variety of tools including satellite phones, online journals, podcasts and interactive "Live from IPY" calls and web-based seminars. The online outreach elements of the project convey these experiences to a broad audience far beyond the classrooms of the PolarTREC teachers. In addition to field research experiences, PolarTREC will support teacher professional development and a sustained community of teachers, scientists, and the public through workshops, Internet seminars, an e-mail listserve, and teacher peer groups. For further information on PolarTREC, contact Wendy Warnick, ARCUS Executive Director at warnick@arcus.org or 907-474-1600 or visit www.arcus.org/trec/

  18. PolarTREC-Teachers and Researchers Exploring and Collaborating: Science Education from the Poles to the World

    Science.gov (United States)

    Warnick, W. K.; Breen, K.; Warburton, J.; Fischer, K.; Wiggins, H.; Owens, R.; Polly, B.; Wade, B.; Buxbaum, T.

    2007-12-01

    PolarTREC-Teachers and Researchers Exploring and Collaborating is a three-year (2007-2009) teacher professional development program celebrating the International Polar Year (IPY) that advances polar science education by bringing K-12 educators and polar researchers together in hands-on field experiences in the Arctic and Antarctic. Currently in its second year, the program fosters the integration of research and education to produce a legacy of long-term teacher-researcher collaborations, improved teacher content knowledge through experiences in scientific inquiry, and broad public interest and engagement in polar science. Through PolarTREC, over 40 U.S. teachers will spend two to six weeks in the Arctic or Antarctic, working closely with researchers in the field as an integral part of the science team. Research projects focus on a wide range of IPY science themed topics such as sea-ice dynamics, terrestrial ecology, marine biology, atmospheric chemistry, and long-term climate change. While in the field, teachers and researchers will communicate extensively with their colleagues, communities, and hundreds of students of all ages across the globe, using a variety of tools including satellite phones, online journals, podcasts and interactive "Live from IPY" calls and web-based seminars. The online outreach elements of the project convey these experiences to a broad audience far beyond the classrooms of the PolarTREC teachers. In addition to field research experiences, PolarTREC will support teacher professional development and a sustained community of teachers, scientists, and the public through workshops, Internet seminars, an e-mail listserve, and teacher peer groups. To learn more about PolarTREC visit the website at: http://www.polartrec.com or contact info@polartrec.com or 907-474-1600. PolarTREC is funded by NSF and managed by the Arctic Research Consortium of the US (ARCUS).

  19. Research and development on optically pumped polarized ion sources. Technical progress report, July 1, 1985-June 30, 1986

    International Nuclear Information System (INIS)

    Anderson, L.W.

    1986-07-01

    The development of an optically pumped polarized 23 Na target is discussed. The three categories of research are: (1) electron spin relaxation of the 23 Na due to wall collisions; (2) effects of radiation trapping on the polarization that can be produced in an alkali target by optical pumping; and (3) the effects of spin exchange collisions in the polarization of a fast H 0 beam formed by charge transfer as an H + beam passes through a polarized alkali target. 90 refs., 7 figs

  20. Joint Polar Satellite System's Operational and Research Applications from Suomi NPP

    Science.gov (United States)

    Goldberg, M.

    2014-12-01

    The Joint Polar Satellite System is NOAA's new operational satellite program and includes the Suomi National Polar-orbiting Partnership (S-NPP) as a bridge between NOAA's operational Polar Orbiting Environmental Satellite (POES) series, which began in 1978, and the first JPSS operational satellite scheduled for launch in 2017. JPSS provides critical data for key operational and research applications, and includes: 1) Weather forecasting - data from the JPSS Cross-track Infrared Sounder (CrIS) and the Advanced Technology Microwave Sounder (ATMS) are needed to forecast weather events out to 7 days. Nearly 85% of all data used in weather forecasting are from polar orbiting satellites. 2) Environmental monitoring - data from the JPSS Visible Infrared Imager Radiometer Suite (VIIRS) are used to monitor the environment including the health of coastal ecosystems, drought conditions, fire, smoke, dust, snow and ice, and the state of oceans, including sea surface temperature and ocean color. 3) Climate monitoring - data from JPSS instruments, including OMPS and CERES will provide continuity to climate data records established using NOAA POES and NASA Earth Observing System (EOS) satellite observations. These data records provide a unified and coherent long-term observation of the environment; the records and products are critical to climate modelers, scientists, and decision makers concerned with advancing climate change understanding, prediction, mitigation and adaptation strategies, and policies. To bridge the gap between products and applications, the JPSS Program has established a proving ground program to optimize the use of JPSS data with other data sources to improve key products and services. A number of operational and research applications will be discussed, including the use of CrIS and ATMS for improved weather forecasting, the use of VIIRS for environmental monitoring of sea ice, smoke, fire, floods, droughts, coastal water quality (e.g. harmful algal blooms

  1. "POLAR-PALOOZA" and "International POLAR-PALOOZA": Taking Researchers on the Road to Engage Public Audiences across America, and Around the World

    Science.gov (United States)

    Haines-Stiles, G.; Akuginow, E.

    2010-12-01

    POLAR-PALOOZA and its companion project, "International POLAR-PALOOZA" shared the same central premise: that polar researchers, speaking for themselves, could be powerful communicators about the science and mission of the 4th International Polar Year, and could successfully engage a wide variety of public audiences across America and around the world. Supported for the US tour by NSF and NASA, and internationally by NSF alone, the project enlisted more than forty American researchers, and 14 polar scientists from Brazil, China and Australia, to participate in events at science centers and natural history museums, universities, public libraries and schools, and also for targeted outreach to special audiences such as young female researchers in Oklahoma, or the Downtown Rotary in San Diego. Evaluations by two different ISE groups found similar results domestically and internationally. When supported by HD video clips and presenting informally in teams of 3, 4, 5 and sometimes even 6 researchers as part of a fast-paced "show," the scientists themselves were almost always rated as among the most important aspects of the program. Significant understandings about polar science and global climate change resulted, along with a positive impression of the research undertaken during IPY. This presentation at Fall AGU 2010 will present results from the Summative Evaluation of both projects, show representative video clips of the public presentations, share photographs of some of the most dramatically varied venues and candid behind-the-scenes action, and share "Lessons Learned" that can be broadly applied to the dissemination of Earth and space science research. These include: collaboration with partner institutions is never easy. (Duh.) Authentic props (such as ice cores, when not trashed by TSA) make a powerful impression on audiences, and give reality to remote places and complex science. And, most importantly, that since 85% of Americans have never met a scientist, that

  2. Getting past the penguins and polar bears - comparing marine research in the Arctic and Antarctic

    Science.gov (United States)

    Stevenoski, S.; Lawver, L.; van Avendonk, H.

    2006-12-01

    The University of Texas Institute for Geophysics is actively involved in marine geophysics research in the Arctic and Antarctic. Over the past 11 years teachers have participated in a number of research cruises as part of their effort to do outreach and involve K-12 teachers directly in the science. This presentation will focus on comparing the differences in weather, ice, seafloor, and biology, observed by one teacher/researcher who participated in seismic cruises in western Arctic and the Bransfield Straight and the Ross Sea in Antarctica. The presentation will focus on how these differences and similarities affect the process of conducting science in these extreme environments. Attention will be placed on describing how aspects of this polar research can be incorporated into a K-12 science curriculum. A discussion of the continuing outreach by the scientists and university will also be included.

  3. Experimental urban heat island research of Norilsk city in northern Russia in the polar night

    Science.gov (United States)

    Varentsov, Mikhail; Konstantinov, Pavel; Repina, Irina; Samsonov, Timofey; Baklanov, Alexander

    2014-05-01

    Growing socioeconomic activity in Arctic zone and prospective of planning and building new settlements and cities in this region requires better understanding of the urban-caused microclimatic features and their behavior in the conditions of arctic and sub-arctic climate. The most important of these features is well-known urban heat island (UHI) effect, because in high latitudes it could mitigate severe climatic conditions within urban areas and provide the economy of fuel for house heating. The UHI effect is quietly good investigated and described for the cities in low and moderate latitudes (Oke, 1987), but there is significant lack of knowledge about UHI of the cities over the Polar Circle and especially about its behavior during the polar night, while anthropogenic heat is the only source of energy to form heat island. In this study, we consider the results of experimental research of the UHI of Norilsk - the second biggest city over the Polar Circle, which were obtained during the expedition of Russian Geographic Society in December 2013, practically around the middle of the polar night. Field measurements in Norilsk included installation of three automatic weather stations (AWS) and the net of small temperature sensors (iButton) in the city and surrounding landscape and also car-based temperature sounding of the city with AWS. The influence of the relief and stratification was filtered by using the data of MTP-5 microwave temperature profiler. Analysis of the collected data showed the existence of significant UHI with the difference between city center and surrounding landscape up to 6 °C. The dependence of UHI power and shape on the synoptic conditions were analyzed for several typical synoptic situations, which were observed during the expedition, and the negative correlation of the UHI power with air temperature was determined. The reported study was supported by Russian Geographic Society, research projects No. 69/2013-H7 and 27/2013-H3. References: 1

  4. The research of urban spatial polarization based on the space of flows theory——a case study of Shanghai

    Directory of Open Access Journals (Sweden)

    LIU Chaoqing

    2013-04-01

    Full Text Available Based on the elite space and the relation model between the space of flows and the urban space,the paper analyzed the mechanism and consequence of the new urban spatial polarization.Using the Shanghai sixth census data and the sample data,the paper discussed the new phenomenon of urban spatial polarization in the information age by the location quotient analysis and GIS spatial analysis.The research result showed that the space of flows influencing urban spatial polarization through the elite space is a higher level agglomeration,including the spatial concentration of the human capital,the concentration of wealth and knowledge of science and technology.

  5. Spatio-temporal variability of the polar middle atmosphere. Insights from over 30 years of research satellite observations

    Energy Technology Data Exchange (ETDEWEB)

    Lahoz, W.A.; Orsolini, Y.J.; Manney, G.L.; Minschwaner, K.; Allen, D.R.; Errera, Q.; Jackson, D.R.; Lambert, A.; Lee, J.; Pumphrey, H.; Schwartz, M.; Wu, D.

    2012-07-01

    We discuss the insights that research satellite observations from the last 30 years have provided on the spatio-temporal variability of the polar middle atmosphere. Starting from the time of the NASA LIMS (Limb Infrared Monitor of the Stratosphere) and TOMS (Total Ozone Mapping Spectrometer) instruments, both launched in 1978, we show how these observations have augmented our knowledge of the polar middle atmosphere, in particular how information on ozone and tracers has augmented our knowledge of: (i) the spatial and temporal characteristics of the wintertime polar stratosphere and the summertime circulation; and (ii) the roles of chemistry and transport in determining the stratospheric ozone distribution. We address the increasing joint use of observations and models, in particular in data assimilation, in contributing to this understanding. Finally, we outline requirements to allow continuation of the wealth of information on the polar middle atmosphere provided by research satellites over the last 30 years.(Author)

  6. Research and development on optically pumped polarized ion sources. Technical progress report, February 1, 1985-January 31, 1986

    International Nuclear Information System (INIS)

    Anderson, L.W.

    1985-07-01

    During the past year we have studied the relaxation times in an optically pumped 23 Na vapor target, studied the effects of radiation trapping on the polarization in a Na vapor target, and have studied the effects of spin exchange collisions on a beam of fast H 0 atoms as they pass through a polarized alkali target. This research is directed toward improvements in the optically pumped Na or other alkali vapor targets used for the production of polarized H - ions. In this progress report we review the properties of the optically pumped polarized H - ion source as well as discussing the progress of our research on optically pumped Na or other alkali vapor targets. 81 refs., 9 figs

  7. NATO Advanced Research Workshop on The Morphology and Dynamics of the Polar Cusp

    CERN Document Server

    Egeland, Alv

    1985-01-01

    These proceedings are based upon introductory talks, research reports and discussions from the NATO Advanced Workshop on the "Morphology and Dynamics of the Polar Cusp", held at Lillehammer, Norway, 7-12 May, 1984. The upper atmosphere at high latitudes is called the "Earth's win­ dow to outer space". Through various electrodynamic coupling process­ es as well as through direct transfer of particles many geophysical effects displayed there are direct manifestations of phenomena occurring in the deep space. The high latitude ionosphere will also exert a feedback on the regions of the magnetosphere and atmosphere to which it is coupled, acting as a momentum and energy source and sink, and a source of particles. Of particular interest are the sections of the near space known as the Polar Cusp. A vast portion of the earth's magnetic field envelope is electrically connected to these regions. This geometry results in a spatial mapping of the magnetospheric pro­ cesses and a focusing on to the ionosphere. In the ...

  8. Polarization developments

    International Nuclear Information System (INIS)

    Prescott, C.Y.

    1993-07-01

    Recent developments in laser-driven photoemission sources of polarized electrons have made prospects for highly polarized electron beams in a future linear collider very promising. This talk discusses the experiences with the SLC polarized electron source, the recent progress with research into gallium arsenide and strained gallium arsenide as a photocathode material, and the suitability of these cathode materials for a future linear collider based on the parameters of the several linear collider designs that exist

  9. Applicability of NASA Polar Technologies to British Antarctic Survey Halley VI Research Station

    Science.gov (United States)

    Flynn, Michael

    2005-01-01

    From 1993 through 1997 NASA and the National Science Foundation (NSF), developed a variety of environmental infrastructure technologies for use at the Amundsen-Scott South Pole Station. The objective of this program was to reduce the cost of operating the South Pole Station, reduce the environmental impact of the Station, and to increase the quality of life for Station inhabitants. The result of this program was the development of a set of sustainability technologies designed specifically for Polar applications. In the intervening eight years many of the technologies developed through this program have been commercialized and tested in extreme environments and are now available for use throughout Antarctica and circumpolar north. The objective of this document is to provide information covering technologies that might also be applicable to the British Antarctic Survey s (BAS) proposed new Halley VI Research Station. All technologies described are commercially available.

  10. Polarization holography

    DEFF Research Database (Denmark)

    Nikolova, L.; Ramanujam, P.S.

    Current research into holography is concerned with applications in optically storing, retrieving, and processing information. Polarization holography has many unique properties compared to conventional holography. It gives results in high efficiency, achromaticity, and special polarization...... properties. This books reviews the research carried out in this field over the last 15 years. The authors provide basic concepts in polarization and the propagation of light through anisotropic materials, before presenting a sound theoretical basis for polarization holography. The fabrication...... and characterization of azobenzene based materials, which remain the most efficient for the purpose, is described in detail. This is followed by a description of other materials that are used in polarization holography. An in-depth description of various applications, including display holography and optical storage...

  11. Present situation of researches on polar ionosphere by C.C.I.R

    International Nuclear Information System (INIS)

    Ishikawa, Saburo

    1974-01-01

    Various subjects of studies made by the sixth research committee of C.C.I.R. (International Radio Consultative Committee) are reported. The C.C.I.R. has not any definite study programme and question concerning polar ionosphere, because it studies and delivers opinion on the techniques and operation of radio communication especially in developing countries. The subjects of study programme by the sixth research committee are as follows: estimation of the intensity and transmission loss of space wave electric field in a zone between 1.5 and 40 MHz, observation of the ionosphere of oblique entrance, scattering propagation of ionosphere, back scattering, fading of signal transmitted through ionosphere, transmission of space waves in the zone between 150 and 1,500 kHz, and effect of ionosphere on space communication. In addition, the following fourteen reports are cited: confirmation of prodromal phenomena of ionosphere disturbances, observation of the ionosphere of oblique entrance, remote propagation with supermode, basic information on forecast, back scattering, side scattering from the ground surface and ionosphere, Esub(s) propagation, scattering propagation, Esub(s) forecast, fading, effect of ionosphere on the transmission between the earth and space, radio noise produced in and above ionosphere, and propagation of standard broadcast wave. (Iwakiri, K.)

  12. CURRÍCULOS DE SECRETARIADO EXECUTIVO: ALGUMAS REFLEXÕES CURRICULUM OF EXECUTIVE SECRETARIAT: SOME REFLECTIONS

    Directory of Open Access Journals (Sweden)

    Aneridis Aparecida Monteiro

    2011-05-01

    Full Text Available

    Ao longo dos últimos anos o curso de graduação em bacharelado em Secretariado Executivo é alvo de concepções errôneas, bem como de comparações equivocadas a outros cursos de áreas afins e/ou nomenclaturas semelhantes. Emerge nesse sentido a necessidade de estudos que tragam de forma esclarecedora, a discussão de como é elaborada a estrutura curricular desse curso de graduação. Dessa forma, este artigo tem como objetivo principal comparar a estrutura curricular de três instituições de ensino superior do Brasil, tendo como objeto de estudo duas universidades públicas e uma privada em três regimes distintos, federal, estadual e privado. Para tanto, parte-se de um levantamento bibliográfico com autores que têm discutido as concepções de currículo, de um modo geral, servindo como base no estudo, bem como à abordagem da Diretriz Curricular Nacional (DCN do curso no intuito de verificar os aspectos igualitários e diferenciais em relação a estas três instituições de ensino superior, onde serão valorizadas esferas de ordem social, institucional e regimentar. As conclusões apontam para a abrangência e relevância do curso de Secretariado Executivo, bem como que as IES analisadas estão adequadas às exigências do Ministério da Educação no tocante à formação acadêmica desses profissionais.

    Along the last years, it is noticed that the degree course in baccalaureate in Executive Secretariat is white of erroneous conceptions, as well as of mistaken comparisons the other courses of similar areas and/or similar nomenclatures. It emerges in that sense the need of studies that you/they swallow in an explanatory way, the discussion of as the curriculum structure of that degree course is elaborated. In that way, this article has as main objective to compare the curriculum structure of three institutions of higher education of Brazil, tends as object of study two public universities

  13. Development of a polarized neutron beam line at Algerian research reactors using McStas software

    Energy Technology Data Exchange (ETDEWEB)

    Makhloufi, M., E-mail: makhloufi_8m@yahoo.fr [Centre de Recherche Nucléaire de Birine (Algeria); Salah, H. [Centre de Recherche Nucléaire d' Alger (Algeria)

    2017-02-01

    Unpolarized instrumentation has long been studied and designed using McStas simulation tool. But, only recently new models were developed for McStas to simulate polarized neutron scattering instruments. In the present contribution, we used McStas software to design a polarized neutron beam line, taking advantage of the available spectrometers reflectometer and diffractometer in Algeria. Both thermal and cold neutron was considered. The polarization was made by two types of supermirrors polarizers FeSi and CoCu provided by the HZB institute. For sake of performance and comparison, the polarizers were characterized and their characteristics reproduced. The simulated instruments are reported. Flipper and electromagnets for guide field are developed. Further developments including analyzers and upgrading of the existing spectrometers are underway. - Highlights: • Permit to evaluate the feasibility of a polarized neutron scattering instrument prior to its implementation. • Help to understand the origin of instrumental imperfections and offer an optimized set up configuration. • Provide the possibility to use the FeSi and CoCu supermirrors, designed to polarize spin up cold neutron, to polarize thermal neutron.

  14. Experimental Urban Heat Island Research of Four Biggest Polar Cities in Northern Hemisphere

    Science.gov (United States)

    Konstantinov, Pavel; Baklanov, Alexander; Varentsov, Mikhail; Kukanova, Evgenia; Repina, Irina; Shuvalov, Sergey; Samsonov, Timofey

    2014-05-01

    Urban Heat Island (UHI) effect is well-known in modern climatology due to its influence on different economic features and urban air quality (Oke, 1987). Also UHI characteristics differs in different climate zones, for example in summer in Mediterranean and subtropical monsoon climate types it leads to growing energy consumption due to AC systems using (Ohashi et al, 2007). But there is only a few papers about UHI (Magee et al, 1999) in high latitudes, for the cities over the Polar Circle and especially about behavior of the heat islands during the polar night, while anthropogenic heat is the main source of thermal energy. The main goal of this study is to mitigate this lack of information about climatology of UHI formation in big cities (with population exceeding 50 000) of Arctic zone. In this paper, we consider the results of experimental research of the UHI of 4 biggest Arctic Cities (Murmansk, Norilsk, Apatity and Vorkuta), which were obtained during the expedition of Russian Geographic Society in 2013-2014. During the project we used a different measurements techniques: 1. Installation of two automatic weather stations (AWS) in rural zone and city center 2. Installation of small temperature sensors (iButton) network in the city and suburbs 3. Regular car-based temperature sounding of the city with AWS. 4. Using MTP-5 microwave temperature profiler. This investigations allowed to collect unique data about UHI in high latitudes. Analysis of the collected data showed the existence of UHI with the difference between city center and surrounding landscape up to few degrees Celcius. UHI characteristics in view of synoptic conditions was analyzed for several typical situations, for some cities (Norilsk) the negative correlation of the UHI power with air temperature was determined. The reported study was supported by RGS (Russian Geographical Society ), research project No.27/2013-NZ References: 1. Magee N., Curtis J., Wendler G., The Urban Heat Island Effect at

  15. Human responses to wave slamming vibration on a polar supply and research vessel.

    Science.gov (United States)

    Omer, H; Bekker, A

    2018-02-01

    A polar supply and research vessel is pre-disposed to wave slamming which has caused complaints among crew and researchers regarding interference with sleep, equipment use and research activities. The present work undertook to survey passenger claims of sleep interference, disturbed motor tasks and equipment damage as a result of wave slamming during normal operations of this vessel. The hypothesis was investigated that whole-body vibration metrics from ISO 2631-1 are potentially suitable for the prediction of human slamming complaints. Full-scale acceleration measurements were performed and wave slamming events were subsequently identified from the human weighted acceleration time histories. A daily diary survey was also conducted to gather the human response. The vibration caused by wave slamming was found to be strongly correlated with sleep disturbances and activity interference. Sleep and equipment use were found to be the most affected parameters by slamming. Daily vibration dose values were determined by accumulating the vibration as a result of slamming over 24 h periods. This metric accounted for increased magnitudes and frequency of slamming incidents and proved to be the best metric to represent human responses to slamming vibration. The greatest percentage of activities affected by slamming related to sleep regardless of daily cumulative VDV magnitude. More than 50% of the recorded responses related to sleep when the daily cumulative VDV ranged between 8.0 m/s 1.75 -10.0 m/s 1.75 . The peak vertical vibration levels recorded on the vessel reach magnitudes which are associated with sleep disturbance in environments where acoustic noise is present. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. A transportable hybrid antenna-transmitter system for the generation of elliptically polarized waves for NVIS propagation research

    NARCIS (Netherlands)

    Witvliet, Ben A.; Laanstra, Geert J.; van Maanen, Erik; Alsina-Pagès, Rosa M.; Bentum, Marinus Jan; Slump, Cornelis H.; Schiphorst, Roelof

    2016-01-01

    For empirical research on Near Vertical Incidence Skywave (NVIS) characteristic wave propagation, a beacon transmitter system is needed that can be programmed to emit precisely defined elliptically and circularly polarized waves at high elevation angles. This paper proposes a novel hybrid

  17. Association of Polar Early Career Scientists: a model for experiential learning in professional development for students and early career researchers

    Science.gov (United States)

    Bradley, A. C.; Hindshaw, R. S.; Fugmann, G.; Mariash, H.

    2016-12-01

    The Association of Polar Early Career Scientists was established by early career researchers during the 2007-2008 International Polar Year as an organization for early career researchers in the polar and cryospheric sciences. APECS works to promote early career researchers through soft-skills training in both research and outreach activities, through advocating for including early career researchers in all levels of the scientific process and scientific management, and through supporting a world-wide network of researchers in varied fields. APECS is lead by early career researchers; this self-driven model has proved to be an effective means for developing the leadership, management, and communication skills that are essential in the sciences, and has shown to be sustainable even in a community where frequent turn-over is inherent to the members. Since its inception, APECS has reached over 5,500 members in more than 80 countries, and we have placed more than 50 early career researchers on working groups and steering committees with organizations around the world in the last two years alone. The close partnerships that APECS has with national and international organizations exposes members to both academic and alternative career paths, including those at the science-policy interface. This paper describes APECS's approach to experiential learning in professional development and the best practices identified over our nearly ten years as an organization.

  18. The Current State of Nanoparticle-Induced Macrophage Polarization and Reprogramming Research

    Directory of Open Access Journals (Sweden)

    Xiaoyuan Miao

    2017-02-01

    Full Text Available Macrophages are vital regulators of the host defense in organisms. In response to different local microenvironments, resting macrophages (M0 can be polarized into different phenotypes, pro-inflammatory (M1 or anti-inflammatory (M2, and perform different roles in different physiological or pathological conditions. Polarized macrophages can also be further reprogrammed by reversing their phenotype according to the changed milieu. Macrophage polarization and reprogramming play essential roles in maintaining the steady state of the immune system and are involved in the processes of many diseases. As foreign substances, nanoparticles (NPs mainly target macrophages after entering the body. NPs can perturb the polarization and reprogramming of macrophages, affect their immunological function and, therefore, affect the pathological process of disease. Optimally-designed NPs for the modulation of macrophage polarization and reprogramming might provide new solutions for treating diseases. Systematically investigating how NPs affect macrophage polarization is crucial for understanding the regulatory effects of NPs on immune cells in vivo. In this review, macrophage polarization by NPs is summarized and discussed.

  19. Focusing and polarized neutron ultra-small-angle scattering spectrometer (SANS-J-II) at Research Reactor JRR3, Japan

    International Nuclear Information System (INIS)

    Koizumi, Satoshi; Iwase, Hiroki; Suzuki, Jun-ichi; Oku, Takayuki; Motokawa, Ryuhei; Sasao, Hajime; Tanaka, Hirokazu; Yamaguchi, Daisuke; Shimizu, Hirohiko M.; Hashimoto, Takeji

    2006-01-01

    By employing focusing lenses of sextupole permanent magnet and biconcave MgF 2 crystal, and high-resolution photomultiplier, SANS-J (pinhole small-angle neutron scattering spectrometer at research reactor JRR3, Tokai) was reconstructed to focusing and polarized neutron ultra-small-angle scattering spectrometer (SANS-J-II). Consequently, an accessible minimum wave number q min was improved from 3x10 -3 A -1 to 3x10 -4 A -1 . Furthermore, we added 3 He sub-detectors with an analyzer super mirror at a sample position. With this setup, we perform polarization analysis at high q (>0.2 A -1 ) in order to quantitatively discriminate spin incoherent scattering from hydrogen or to perform spin contrast variation, by a dynamic nuclear polarization method (>0.2 A -1 )

  20. Conflict-of-interest disclosure at medical journals in Japan: a nationwide survey of the practices of journal secretariats.

    Science.gov (United States)

    Kojima, Takako; Green, Joseph; Barron, J Patrick

    2015-08-26

    Medical journals in Japan generally have appropriate policies regarding disclosure of conflicts of interest (COI). However, COI management depends on the staff members of each journal's editorial secretariat. This study's objectives were to find out (A) whether COI disclosure and the journal's role in it are clearly understood by the journal's secretariat staff, (B) how much experience the editorial secretariat has in actually handling issues related to disclosure and (C) what kind of help or support they need. In January 2014, questionnaires were sent to the editorial secretariats of journal-publishing societies belonging to the Japanese Association of Medical Sciences (JAMS). The response rate was 100%, and the respondents represented 121 journals published by the 118 JAMS member societies (at the time of the survey). Information was collected on the history of COI policies and on how those policies were implemented. At the end of the questionnaire, there was an open-ended call for comments. Compulsory COI disclosure began between 2010 and 2013 for 60.3% of the journals (73/121). Handling of COI issues was not uniform: 17.4% (21/121) of respondents do not pursue cases of dubious disclosure, and 47.9% (58/121) do not require COI disclosures from editorial board members. Very few of the editorial secretariats had clearly-stated consequences for violations of COI-disclosure policy (33/121, 27.3%), and only 28.9% offered COI education (35/121). Respondents' comments indicated that uniform, easily-searchable guidance regarding COI policies and implementation would be welcome. Although commitment is widespread, policy implementation is inconsistent and COI experience is lacking. Clear, easy-to-use guidelines are desired by many societies. The JAMS is to be commended for supporting this country-wide investigation; other countries and regions are encouraged to perform similar investigations to respond to needs regarding COI management. Published by the BMJ Publishing

  1. [The research of the relationship between snow properties and the bidirectional polarized reflectance from snow surface].

    Science.gov (United States)

    Sun, Zhong-Qiu; Wu, Zheng-Fang; Zhao, Yun-Sheng

    2014-10-01

    In the context of remote sensing, the reflectance of snow is a key factor for accurate inversion for snow properties, such as snow grain size, albedo, because of it is influenced by the change of snow properties. The polarized reflectance is a general phenomenon during the reflected progress in natural incident light In this paper, based on the correct measurements for the multiple-angle reflected property of snow field in visible and near infrared wavelength (from 350 to 2,500 nm), the influence of snow grain size and wet snow on the bidirectional polarized property of snow was measured and analyzed. Combining the results measured in the field and previous conclusions confirms that the relation between polarization and snow grain size is obvious in infrared wavelength (at about 1,500 nm), which means the degree of polarization increasing with an increase of snow grain size in the forward scattering direction, it is because the strong absorption of ice near 1,500 nm leads to the single scattering light contributes to the reflection information obtained by the sensor; in other word, the larger grain size, the more absorption accompanying the larger polarization in forward scattering direction; we can illustrate that the change from dry snow to wet snow also influences the polarization property of snow, because of the water on the surface of snow particle adheres the adjacent particles, that means the wet snow grain size is larger than the dry snow grain size. Therefore, combining the multiple-angle polarization with reflectance will provide solid method and theoretical basis for inversion of snow properties.

  2. CELSS Antarctic Analog Project (CAAP): A New Paradigm for Polar Life Support and CELSS Research

    Science.gov (United States)

    Bubenheim, David L.; Straight, Christian; Flynn, Michael; Bates, Maynard; Harper, Lynn D. (Technical Monitor)

    1994-01-01

    The CELSS Antarctic Analog Project (CAAP) is a joint National Science Foundation (NSF) and National Aeronautics and Space Administration (NASA) project for the development, deployment and operation of CELSS technologies at the Amundsen-Scott South Pole Station. CAAP is implemented through the joint NSF/NASA Antarctic Space Analog Program (ASAP), initiated to support the pursuit of future NASA missions and to promote the transfer of space technologies to the NSF. Under a Memorandum of Agreement, the CAAP represents an example of a working dual agency cooperative project. NASA goals are operational testing of CELSS technologies and the conduct of scientific study to facilitate . technology selection, system design and methods development, including human dynamics as required for the operation of a CELSS. Although not fully closed, food production, water purification, and waste recycle and reduction provided by CAAP will improve the quality of life for the South Pole inhabitants, reduce logistics dependence, and minimize environmental impacts associated with human presence on the polar plateau. The CAAP facility will be highly integrated with the new South Pole Station infrastructure and will be composed of a deployed hardware facility and a research activity. This paper will include a description of CAAP and its functionality, conceptual designs, component selection and sizing for the crop growth chamber, crop production expectations, and a brief report on an initial on-site visit. This paper will also provide a discussion of issues associated with power and energy use and the applicability of CAAP to direct technology transfer to society in general and remote communities in particular.

  3. The Suomi National Polar-Orbiting Partnership (SNPP): Continuing NASA Research and Applications

    Science.gov (United States)

    Butler, James; Gleason, James; Jedlovec, Gary; Coronado, Patrick

    2015-01-01

    The Suomi National Polar-orbiting Partnership (SNPP) satellite was successfully launched into a polar orbit on October 28, 2011 carrying 5 remote sensing instruments designed to provide data to improve weather forecasts and to increase understanding of long-term climate change. SNPP provides operational continuity of satellite-based observations for NOAA's Polar-orbiting Operational Environmental Satellites (POES) and continues the long-term record of climate quality observations established by NASA's Earth Observing System (EOS) satellites. In the 2003 to 2011 pre-launch timeframe, NASA's SNPP Science Team assessed the adequacy of the operational Raw Data Records (RDRs), Sensor Data Records (SDRs), and Environmental Data Records (EDRs) from the SNPP instruments for use in NASA Earth Science research, examined the operational algorithms used to produce those data records, and proposed a path forward for the production of climate quality products from SNPP. In order to perform these tasks, a distributed data system, the NASA Science Data Segment (SDS), ingested RDRs, SDRs, and EDRs from the NOAA Archive and Distribution and Interface Data Processing Segments, ADS and IDPS, respectively. The SDS also obtained operational algorithms for evaluation purposes from the NOAA Government Resource for Algorithm Verification, Independent Testing and Evaluation (GRAVITE). Within the NASA SDS, five Product Evaluation and Test Elements (PEATEs) received, ingested, and stored data and performed NASA's data processing, evaluation, and analysis activities. The distributed nature of this data distribution system was established by physically housing each PEATE within one of five Climate Analysis Research Systems (CARS) located at either at a NASA or a university institution. The CARS were organized around 5 key EDRs directly in support of the following NASA Earth Science focus areas: atmospheric sounding, ocean, land, ozone, and atmospheric composition products. The PEATES provided

  4. Research progress of anti-icing/deicing technologies for polar ships and offshore platforms

    Directory of Open Access Journals (Sweden)

    XIE Qiang

    2017-01-01

    Full Text Available The polar regions present adverse circumstances of high humidity and strong air-sea exchange. As such, the surfaces of ships and platforms (oil exploiting and drilling platforms serving in polar regions can easily be frozen by ice accretion, which not only affects the operation of the equipment but also threatens safety. This paper summarizes the status of the anti-icing/deicing technologies of both China and abroad for polar ships and offshore platforms, and introduces the various effects of ice accretion on polar ships and offshore platforms, and the resulting safety impacts. It then reviews existing anti-icing/deicing technologies and methods of both China and abroad, including such active deicing methods as electric heating, infrared heating and ultrasonic guided wave deicing, as well as such passive deicing methods as super hydrophobic coating, sacrificial coating, aqueous lubricating layer coating and low cross-link density (with interfacial slippage coating, summarizes their applicability to polar ships and offshore platforms, and finally discusses their advantages/disadvantages.

  5. Polar Bears

    Science.gov (United States)

    Amstrup, Steven C.; Douglas, David C.; Reynolds, Patricia E.; Rhode, E.B.

    2002-01-01

    Polar bears (Ursus maritimus) are hunted throughout most of their range. In addition to hunting polar bears of the Beaufort Sea region are exposed to mineral and petroleum extraction and related human activities such as shipping road-building, and seismic testing (Stirling 1990).Little was known at the start of this project about how polar bears move about in their environment, and although it was understood that many bears travel across political borders, the boundaries of populations had not been delineated (Amstrup 1986, Amstrup et al. 1986, Amstrup and DeMaster 1988, Garner et al. 1994, Amstrup 1995, Amstrup et al. 1995, Amstrup 2000).As human populations increase and demands for polar bears and other arctic resources escalate, managers must know the sizes and distributions of the polar bear populations. Resource managers also need reliable estimates of breeding rates, reproductive intervals, litter sizes, and survival of young and adults.Our objectives for this research were 1) to determine the seasonal and annual movements of polar bears in the Beaufort Sea, 2) to define the boundaries of the population(s) using this region, 3) to determine the size and status of the Beaufort Sea polar bear population, and 4) to establish reproduction and survival rates (Amstrup 2000).

  6. An Investigation of Scientific Production of Executive Secretariat Graduates At the Federal University of Ceará From 2010 to 2015

    Directory of Open Access Journals (Sweden)

    Márcia Monalisa Garcia

    2017-05-01

    Full Text Available The culture of research in Executive Secretary course is recent and has been widely promoted in the academic and scientific community. Therefore, this study aims to analyze the scientific production of graduates from the Executive Secretariat Course at the Federal University of Ceará (UFC from 2010 to 2015, in order to verify their contributions to the increase of scientific production in the field. In order to achieve the proposed objectives, a descriptive, bibliographic research was carried out with quantitative and qualitative approach, using as basis for data analysis a review on the content "Productions" of the Brazilian database résumé (Curriculum Lattes, of UFC graduates since the foundation of the course in 1995, to the year 2015. Among the main results, the research pointed out the need for diversification on the types of scientific contribution, since most of it has focused on paper presentations; also diversifying the researched topics, since most of them focused on professional practice, highlighting the focus on the technicist character of this profession. There has also been a significant increase in scientific production in the years 2013 and 2014. This work has raised the importance of spreading a new mentality about the secretarial studies, stimulating the production of new knowledge in this field.

  7. Leaving School — learning at SEA: Regular high school education alongside polar research

    Science.gov (United States)

    Gatti, Susanne

    2010-05-01

    Against the background of unsatisfactory results from the international OECD study PISA (Program for International Student Assessment), Germany is facing a period of intense school reforms. Looking back at a tradition of school culture with too few changes during the last century, quick and radical renewal of the school system is rather unlikely. Furthermore students are increasingly turning away from natural sciences [1]. The AWI aims at providing impulses for major changes in the schooling system and is offering solid science education not only for university students but also for a larger audience. All efforts towards this goal are interconnected within the project SEA (Science & Education @ the AWI). With the school-term of 2002/03 the Alfred-Wegener-Institute for Polar and Marine Research started HIGHSEA (High school of SEA). The program is the most important component of SEA. Each year 22 high school students (grade 10 or 11) are admitted to HIGHSEA spending their last three years of school not at school but at the institute. Four subjects (biology as a major, chemistry, math and English as accessory subjects) are combined and taught fully integrated. Students leave their school for two days each week to study, work and explore all necessary topics at the AWI. All of the curricular necessities of the four subjects have been rearranged in their temporal sequencing thus enabling a conceptual formulation of four major questions to be dealt with in the course of the three-year program [2]. Students are taught by teachers of the cooperation schools as well as by scientists of the AWI. Close links and intense cooperation between both groups are the basis of fundamental changes in teaching and learning climate. We are organizing expeditions for every group of HIGHSEA-students (e. g. to the Arctic or to mid-Atlantic seamounts). For each student expedition we devise a "real" research question. Usually a single working group at the AWI has a special interest in the

  8. Research on Polarization Cancellation of Nonstationary Ionosphere Clutter in HF Radar System

    Directory of Open Access Journals (Sweden)

    Xingpeng Mao

    2015-01-01

    Full Text Available Oblique projection polarization filter (OPPF can be applied as an effective approach for interference cancellation in high-frequency surface wave radar (HFSWR and other systems. In order to suppress the nonstationary ionosphere clutter further, a novel OPPF based clutter suppressing scheme is proposed in this paper. The polarization and nonstationary characteristic of the clutter are taken into account in the algorithms referred to as range-Doppler domain polarization suppression (RDDPS and the range-time domain polarization suppression (RTDPS method, respectively. The RDDPS is designed for weak ionosphere clutter and implemented in the range-Doppler domain directly, whereas the RTDPS algorithm is designed to suppress the powerful ionosphere clutter with a multisegment estimation and suppression scheme. About 15–23 dB signal to interference ratio (SIR improvement can be excepted when using the proposed method, whereas the targets can be more easily detected in the range-Doppler map. Experimental results demonstrate that the scheme proposed is effective for nonstationary ionosphere clutter and is proven to be a practical interference cancellation technique for HFSWR.

  9. Reflection performance research of grating with polarization independence based on a sandwiched structure

    Science.gov (United States)

    Pei, Hao; Wang, Bo; Zhu, Wenhua; Yin, Sufang; Chen, Li; Lei, Liang; Zhou, Jinyun

    2018-02-01

    The novel reflective grating was studied under Littrow incidence as one sort of high-efficiency optical element. A covering layer and a dielectric layer are employed in this structure to achieve higher efficiency and wider bandwidth. For the given wavelength of 1550 nm, by using two-beam-interference theory of modal method, duty cycle and period of grating can be calculated, where the physical essence of high efficiency in the first-order is well explained by the modal method. The other grating parameters are optimized by using rigorous coupled-wave analysis. The optimized grating has an appropriate aspect ratio and shows that diffraction efficiencies of TE and TM polarizations in the first-order are greater than 97%. Compared with the reported surface-relief high-efficiency grating, the diffraction efficiencies of the proposed grating for TE and TM polarizations can be greatly improved.

  10. Research on Copy-Move Image Forgery Detection Using Features of Discrete Polar Complex Exponential Transform

    Science.gov (United States)

    Gan, Yanfen; Zhong, Junliu

    2015-12-01

    With the aid of sophisticated photo-editing software, such as Photoshop, copy-move image forgery operation has been widely applied and has become a major concern in the field of information security in the modern society. A lot of work on detecting this kind of forgery has gained great achievements, but the detection results of geometrical transformations of copy-move regions are not so satisfactory. In this paper, a new method based on the Polar Complex Exponential Transform is proposed. This method addresses issues in image geometric moment, focusing on constructing rotation invariant moment and extracting features of the rotation invariant moment. In order to reduce rounding errors of the transform from the Polar coordinate system to the Cartesian coordinate system, a new transformation method is presented and discussed in detail at the same time. The new method constructs a 9 × 9 shrunk template to transform the Cartesian coordinate system back to the Polar coordinate system. It can reduce transform errors to a much greater degree. Forgery detection, such as copy-move image forgery detection, is a difficult procedure, but experiments prove our method is a great improvement in detecting and identifying forgery images affected by the rotated transform.

  11. Effects of capturing and collaring on polar bears: findings from long-term research on the southern Beaufort Sea population

    Science.gov (United States)

    Rode, Karyn D.; Pagano, Anthony M.; Bromaghin, Jeffrey F.; Atwood, Todd C.; Durner, George M.; Simac, Kristin S.; Amstrup, Steven C.

    2014-01-01

    Context: The potential for research methods to affect wildlife is an increasing concern among both scientists and the public. This topic has a particular urgency for polar bears because additional research is needed to monitor and understand population responses to rapid loss of sea ice habitat.Aims: This study used data collected from polar bears sampled in the Alaska portion of the southern Beaufort Sea to investigate the potential for capture to adversely affect behaviour and vital rates. We evaluated the extent to which capture, collaring and handling may influence activity and movement days to weeks post-capture, and body mass, body condition, reproduction and survival over 6 months or more.Methods: We compared post-capture activity and movement rates, and relationships between prior capture history and body mass, body condition and reproductive success. We also summarised data on capture-related mortality.Key results: Individual-based estimates of activity and movement rates reached near-normal levels within 2–3 days and fully normal levels within 5 days post-capture. Models of activity and movement rates among all bears had poor fit, but suggested potential for prolonged, lower-level rate reductions. Repeated captures was not related to negative effects on body condition, reproduction or cub growth or survival. Capture-related mortality was substantially reduced after 1986, when immobilisation drugs were changed, with only 3 mortalities in 2517 captures from 1987–2013.Conclusions: Polar bears in the southern Beaufort Sea exhibited the greatest reductions in activity and movement rates 3.5 days post-capture. These shorter-term, post-capture effects do not appear to have translated into any long-term effects on body condition, reproduction, or cub survival. Additionally, collaring had no effect on polar bear recovery rates, body condition, reproduction or cub survival.Implications: This study provides empirical evidence that current capture

  12. Research on disk amplifiers as polarizer of electro-optical switch

    International Nuclear Information System (INIS)

    Zheng Kuixing; Cai Bangwei; Feng Bin; Zheng Jiangang; Dong Yun; Peng Zhitao; Lu Jingping; Jing Feng; Wei Xiaofeng

    2002-01-01

    It benefits to decrease the engineering cost and to debase the technical crisis by the polarizer composed of amplifier Nd 3+ : glass slabs located with the Brewster angle in large scale multi-passes laser facility. The relationships of the isolation efficiency with the numbers of slab, the growth of the amplifier and the switch efficiency of Pockels cell are calculated theoretically. The experimental results indicated that the output energy ratio of this Pockels cell-amplifier isolation system is 1 : 8 while Pockels cell is on and off

  13. Research on disk amplifiers as polarizer of electro-optical switch

    CERN Document Server

    Zheng Kui Xing; Feng Bin; Zheng Jian; Dong Yun; Peng Zhi Tao; Lu Jing Ping; Jing Feng; Wei Xiao Feng

    2002-01-01

    It benefits to decrease the engineering cost and to debase the technical crisis by the polarizer composed of amplifier Nd sup 3 sup + : glass slabs located with the Brewster angle in large scale multi-passes laser facility. The relationships of the isolation efficiency with the numbers of slab, the growth of the amplifier and the switch efficiency of Pockels cell are calculated theoretically. The experimental results indicated that the output energy ratio of this Pockels cell-amplifier isolation system is 1 : 8 while Pockels cell is on and off

  14. Archive of Geosample Data and Information from the Ohio State University Byrd Polar and Climate Research Center (BPCRC) Sediment Core Repository

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Byrd Polar and Climate Research Center (BPCRC) Sediment Core Repository operated by the Ohio State University is a partner in the Index to Marine and Lacustrine...

  15. Polarization Optics

    OpenAIRE

    Fressengeas, Nicolas

    2010-01-01

    The physics of polarization optics *Polarized light propagation *Partially polarized light; DEA; After a brief introduction to polarization optics, this lecture reviews the basic formalisms for dealing with it: Jones Calculus for totally polarized light and Stokes parameters associated to Mueller Calculus for partially polarized light.

  16. Factors Affecting The Career Development Of Employees In Secretariat Office Of City Samarinda

    OpenAIRE

    Santi Rande; Yunus Rahawarin; A. Jamaluddin; Tehubijuluw Zacharias

    2015-01-01

    ABSTRACT Although the primary responsibility for career planning lies in the individual but organizational career planning should be completely in line with individual career planning if an organization wants to retain the best employees. Assumptions and the perspective delivers the researchers to examine the influence of aspects of individual and organizational aspects of the career development of employees within the organization of government. The population in this study were employees of...

  17. ETHIC AND SECRECY ON THE CORPORATE ENVIRONMENT AND THE SECRETARIAT PROFESSIONALS

    Directory of Open Access Journals (Sweden)

    Maria do Carmo Whitaker

    2010-09-01

    Full Text Available This paper, based on theoretical and field research, aims at showing the importance of preserving confidentiality on a daily basis in the context of an "ethical company”. It reports how this practice besides solidifying the image of the organization can also guarantee the existence of a high level of trust and respect between the participants emphasizing the importance of secretarial professionals in that mission. Besides being a regulated profession, which has a code of ethics with explicit determinations about the importance of confidentiality, secrecy is one of the attributes required for the job. The secretaries are aware and convinced of the necessity of secrecy not only in the exercise of their profession, but in their private lives, considering that private interests should not outweigh the public interest.

  18. [Communication and citizenship empowerment in health care: a case of action-research in a polarized Venezuela].

    Science.gov (United States)

    Nahón Serfaty, Isaac; Eid, Mahmoud

    2015-07-01

    An action-research project was implemented in Venezuela from 2009-2013 to empower social activists and patients in their fight against breast cancer (BC). The project was implemented in a context of high political and social polarization of the so-called «Bolivarian revolution». Based on an ecological perspective of health activism and communication, that encompasses the interpersonal, group and social levels, a series of activities were celebrated to develop the advocacy capabilities of citizens, especially women, expand the collaborative networks among different stakeholders, and promote a consensual view between social and institutional actors about a national response to fight BC. A horizontal and participatory communication allowed that the voice of usually marginalized actors was heard in the process of shaping health care policy.

  19. PERFIL DOS DISCENTES (INGRESSANTES E CONCLUINTES DE SECRETARIADO EXECUTIVO: UM ESTUDO COMPARATIVO NAS INSTITUIÇÕES DE ENSINO SUPERIOR (IES PÚBLICAS EXECUTIVE SECRETARIAT STUDENTS´ PROFILE (FRESHMEN AND SENIORS: A COMPARATIVE STYDY IN PUBLIC EDUCATION INSTITUTIONS

    Directory of Open Access Journals (Sweden)

    Vania Souza Bilert

    2012-05-01

    Full Text Available

    O objetivo deste artigo é identificar o perfil dos discentes, ingressantes e concluintes, dos cursos de graduação em secretariado executivo. A pesquisa foi realizada com os discentes de 11 Instituições de Ensino Superior (IES públicas brasileiras, estaduais e federais. O estudo configura-se como descritivo-exploratório, fazendo parte da amostra 507 discentes, sendo 311 ingressantes e 196 concluintes. Os principais resultados indicam que os discentes atuam em empresas de diversos segmentos, com destaque ao comércio e prestação de serviços; 87% são do gênero feminino e a faixa etária predominante é entre 17 a 24 anos. Destaca-se, como fator positivo, a atuação profissional dos discentes desde o início da graduação, exercendo as atribuições pertinentes ao profissional de secretariado executivo, o que revela que os discentes conseguem relacionar o que é aprendido em sala de aula com a prática profissional, o que também evidencia a aceitação do empresariado pelos profissionais de secretariado executivo.

    The objective of this paper is to identify the profile of beginner and graduate students who apply for Executive Secretariat graduation course. This research was carried out with students from 11 Brazilian public undergraduate schools, both federal and state ones. This is considered a descriptive and exploratory study, which analyzed 507 students, 311 beginners and 196 graduate ones. The main results show that students perform in different segment companies, but especially in service companies, 87% are female and the predominant age group is between 17 and 24 years old. In a positive way, this research stands out the factor that these students perform professionally since the beginning of the graduation, exerting the functions which are up to the Executive Secretariat professional. This reveals that the students are able to link what they have learned inside the classroom with the

  20. Implementing SPRINTT [Student Polar Research with IPY National(and International)Teacher Training] in 5th Grade Science

    Science.gov (United States)

    Glass, D. S.

    2009-12-01

    I implemented the new NSF-funded SPRINTT (Student Polar Research with IPY National (and International) Teacher Training) curriculum with a 5th grade science class. SPRINTT, developed at U.S. Satellite Laboratory, Inc., is a 5-8 week science program teaching 5th through 10th graders to investigate climate change using polar data. The program includes perspectives of both Western scientists and the indigenous Northern population. The course contains three phases: Phase 1 includes content, data interpretation, and hands-on experiments to study Frozen Water, Frozen Land, and Food; Phase 2 (optional) includes further content on specific polar topics; and Phase 3 is a scaffolded research investigation. Before the course, teachers were trained via live webinars. This curriculum capitalizes on children’s innate fascination with our planet’s final frontier and combines it with the politically and scientifically relevant topic of climate change. In 2009, I used SPRINTT with 23 heterogeneous fifth grade students at National Presbyterian School in Washington DC for an environmental science unit. Overall, it was a success. The students met most of the learning objectives and showed enthusiasm for the material. I share my experiences to help other educators and curriculum developers. The Phase 1 course includes earth science (glaciers, sea ice, weather and climate, greenhouse gases, seasons, and human impacts on environments), life science (needs of living things, food and energy transfer, adaptations, and ecosystems and biomes) and physical science (phases of matter). Tailoring the program, I focused on Phase 1, the most accessible material and content, while deemphasizing the more cumbersome Phase 3 online research project. Pre-assessments documented the students’ misconceptions and informed instruction. The investigations were appropriately educational and interesting. For example, students enjoyed looking at environmental factors and their impact on the people in the

  1. Leaving School — learning at SEA: Regular high school education alongside polar research, not only during IPY

    Science.gov (United States)

    Gatti, S.

    2006-12-01

    their final exams — with outstanding results. External evaluation of HIGHSEA performed by the University Duisburg-Essen presents spectacular results of HIGHSEA students when compared with a control group. By exploring and establishing new ways of teaching and learning we are contributing to the ongoing discussion about the renewal of the German school system. Drawing on our rich experience in cooperation with local schools we are offering an international role-play game focusing around the sustainable use of Polar regions in times of global climate change. After regional, national and international runs of the game the activities will culminate during an international "World Youth Polar Conference" (WYPC) late in 2007. We offer the unique opportunity for researchers in the field of polar research to actively contribute to a major outreach activity during IPY and participate in our role-play as national ambassadors.

  2. Government liquidates secretariat

    Index Scriptorium Estoniae

    2008-01-01

    Läti valitsus kaotab kulude kokkuhoidmiseks Euroopa Liidu fondide sekretariaadi ja Euroopa Liidu Informatsiooni Agentuuri. Nende asutuste ülesanded delegeeritakse rahandusministeeriumile ja Riigikantseleile

  3. Pesticide usage pattern for vegetable cultivation in Manmunai South & Eruvilpattu divisional secretariat Division of Batticaloa district, Sri Lanka

    Directory of Open Access Journals (Sweden)

    S. Sutharsan

    2014-06-01

    Full Text Available Batticaloa, is a coastal district in Sri Lanka. Vegetables except up-country vegetables sold in Batticaloa District are mainly grown in villages. Manmunai South and Eruvilpattu divisional secretariat (DS division is a predominantly vegetable cultivating area in the Batticaloa district. Farmers in this region use variety of synthetic pesticides to protect vegetables. Recently public concern related to health risks associated with pesticide residues has been increased, substantially. Therefore, a study was conducted to find out pesticide usage practices of farmers on vegetable cultivation in Manmunai South and Eruvilpattu DS division. Stratified random sampling method was used to select respondents’ for the survey and the collected data were analyzed statistically. It was observed that, the usage of pesticides was higher in the study area. Vegetable farmers use more than 14 Insecticides to control pest infestation. Farmers in the study area apply pesticides more frequently. Highly pesticide sprayed crop is Brinjal. About 66% of the Chilli producing farmers and 84% of the Brinjal producing farmers apply pesticide more than 22 times per cropping season. Around 90% of the farmers apply more than the recommended dosage and frequency of the pesticides. It was noticed that more than 89% of the farmers harvest the produce before the recommended pre harvest interval. It was found out that farmers in the study area are not following recommended pesticide usage practices. Hence, it is essential to educate the farmers on recommended pesticide usage practices, reduced usage of synthetic pesticides and use of organic farming practices to reduce the ill effects of synthetic pesticides.

  4. Integrating Access to Arctic Environmental Change and Human Health Research for the International Polar Year and Beyond

    Science.gov (United States)

    Garrett, C. L.

    2006-12-01

    hosting the Arctic Human Health Initiative (AHHI), the human health focus of the International Polar Year activities. AHHI will coordinate research in the areas of infectious disease; the effects of anthropogenic pollution, UV radiation, and climate variability on human health; and telehealth innovations. A major goal of AHHI is the better integration of the findings of Arctic health research through outreach programs and public education.

  5. Our Polar Past

    Science.gov (United States)

    Clary, Renee; Wandersee, James

    2009-01-01

    The study of polar exploration is fascinating and offers students insights into the history, culture, and politics that affect the developing sciences at the farthest ends of Earth. Therefore, the authors think there is value in incorporating polar exploration accounts within modern science classrooms, and so they conducted research to test their…

  6. Polar Science Is Cool!

    Science.gov (United States)

    Weeks, Sophie

    2012-01-01

    Children are fascinated by the fact that polar scientists do research in extremely cold and dangerous places. In the Arctic they might be viewed as lunch by a polar bear. In the Antarctic, they could lose toes and fingers to frostbite and the wind is so fast it can rip skin off. They camp on ice in continuous daylight, weeks from any form of…

  7. 2013 POLAR MARINE SCIENCE GORDON RESEARCH CONFERENCE AND GORDON RESEARCH SEMINAR (MARCH 10-15, 2013 - FOUR POINTS SHERATON, VENTURA CA)

    Energy Technology Data Exchange (ETDEWEB)

    Bowman, Jeff S.

    2012-12-15

    As dynamic and thermodynamic processes associated with warming trends are impacting sea ice cover, oceanographic processes and atmosphere-ocean interactions across polar regions at unprecedented rate, observations and models show fundamentally different regional ecosystem responses. The non-linear and multi-directional biogeochemical responses of polar systems to atmospheric and oceanographic forcings emphasize the need to consider and reconcile observations and models at global and regional scales. The 9th GRC on Polar Marine Science will discuss recent developments and challenges emerging from contemporary and paleo-climate observations and models, encompassing regional and global scales. The GRC addresses the structure, functionalities and controls of polar marine systems through topics such as sea ice biogeochemistry, atmosphere-ocean forcings and interactions, food web trophodynamics, carbon and elemental cycling and fluxes, and a spectrum of ecological processes and interactions.

  8. The Sub-Polar Gyre Index - a community data set for application in fisheries and environment research

    Science.gov (United States)

    Berx, Barbara; Payne, Mark R.

    2017-04-01

    Scientific interest in the sub-polar gyre of the North Atlantic Ocean has increased in recent years. The sub-polar gyre has contracted and weakened, and changes in circulation pathways have been linked to changes in marine ecosystem productivity. To aid fisheries and environmental scientists, we present here a time series of the Sub-Polar Gyre Index (SPG-I) based on monthly mean maps of sea surface height. The established definition of the SPG-I is applied, and the first EOF (empirical orthogonal function) and PC (principal component) are presented. Sensitivity to the spatial domain and time series length are explored but found not to be important factors in terms of the SPG-I's interpretation. Our time series compares well with indices presented previously. The SPG-I time series is freely available online (http://dx.doi.org/10.7489/1806-1), and we invite the community to access, apply, and publish studies using this index time series.

  9. Polarization, political

    NARCIS (Netherlands)

    Wojcieszak, M.; Mazzoleni, G.; Barnhurst, K.G.; Ikeda, K.; Maia, R.C.M.; Wessler, H.

    2015-01-01

    Polarization has been studied in three different forms: on a social, group, and individual level. This entry first focuses on the undisputed phenomenon of elite polarization (i.e., increasing adherence of policy positions among the elites) and also outlines different approaches to assessing mass

  10. Physical trajectory profile data from glider ru25d deployed by Korea Polar Research Institute in the Southern Oceans from 2014-01-04 to 2014-01-13 (NCEI Accession 0145709)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — KOPRI is an international collaboration between the Korean Polar Research Institute and Rutgers University to deploy gliders in the Amundsen polynya. The ice sheets...

  11. Physical trajectory profile data from glider ru24 deployed by Korea Polar Research Institute in the Southern Oceans from 2014-01-04 to 2014-01-13 (NCEI Accession 0145708)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — KOPRI is an international collaboration between the Korean Polar Research Institute and Rutgers University to deploy gliders in the Amundsen polynya. The ice sheets...

  12. Physical trajectory profile data from glider ru25d deployed by Korea Polar Research Institute in the Southern Oceans from 2016-01-21 to 2016-02-06 (NCEI Accession 0153546)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — KOPRI is an international collaboration between the Korean Polar Research Institute and Rutgers University to deploy gliders in the Amundsen polynya. The ice sheets...

  13. Determinants of Success of Small Business: A Survey-Based Study in Kuliyapitiya Divisional Secretariat of Sri Lanka

    OpenAIRE

    Jothiratne Ganithage Sri Ranjith

    2014-01-01

    This study primarily aims to examine the determinants of the success of small business. Kuliyapitiya region in Sri Lanka was selected to carry out this research. The results show number of key significant factors for the success of small business. These factors are the family background of the entrepreneur, ability to make decisions, level of training and the amount of money invested on the business. The results indicate that these qualities of entrepreneur tend to be crucially important for ...

  14. An Analysis of Secretarial Consultancy as a New Market Niche and as a Subject in Executive Secretariat Courses

    Directory of Open Access Journals (Sweden)

    Caroline Jane Schmitz

    2015-08-01

    Full Text Available This study aims at promoting a reflection about secretarial consultancy, showing the transformation of the secretariat’s profession throughout the years, as well as the new competencies of this professional, who rises in the consultancy sector. The hypothesis for the study is that, although the curricular guidelines anticipate a consultant executive secretary professional, this profile is little explored by companies and high educational institutions. In this sense, with the purpose of learning about the changes in the executive secretary’s profile and establishing a relation with the profile required from the business in consultancy, documentary research on the National Curricular Guidelines of the Executive Secretary course was performed, as well as a bibliographical research, both considering authors who trace the executive secretary’s profile and who show the profile of consultants in general. Subsequently, after identifying the high educational institutions in Brazil which offer the Executive Secretary course, through documentary research on Inep website, their curriculum concerning the importance given to consultancy in each course was also investigated. The research is descriptive-exploratory, with qualitative approach, using concomitantly quantitative data collection to map institutions, and qualitative approach to analyze the treatment given to the Consultancy subject in the courses. It can be concluded that, despite the fact that consultancy is a promising branch of activity and the Curricular Guidelines direct to such content, there are few high educational institutions that have the subject in their curriculum, which demands a reflection about the professional intended to be shaped for the current market.

  15. Political polarization

    OpenAIRE

    Dixit, Avinash K.; Weibull, Jörgen W.

    2007-01-01

    Failures of government policies often provoke opposite reactions from citizens; some call for a reversal of the policy, whereas others favor its continuation in stronger form. We offer an explanation of such polarization, based on a natural bimodality of preferences in political and economic contexts and consistent with Bayesian rationality.

  16. Political polarization.

    Science.gov (United States)

    Dixit, Avinash K; Weibull, Jörgen W

    2007-05-01

    Failures of government policies often provoke opposite reactions from citizens; some call for a reversal of the policy, whereas others favor its continuation in stronger form. We offer an explanation of such polarization, based on a natural bimodality of preferences in political and economic contexts and consistent with Bayesian rationality.

  17. Determinants of Success of Small Business: A Survey-Based Study in Kuliyapitiya Divisional Secretariat of Sri Lanka

    Directory of Open Access Journals (Sweden)

    Jothiratne Ganithage Sri Ranjith

    2014-06-01

    Full Text Available This study primarily aims to examine the determinants of the success of small business. Kuliyapitiya region in Sri Lanka was selected to carry out this research. The results show number of key significant factors for the success of small business. These factors are the family background of the entrepreneur, ability to make decisions, level of training and the amount of money invested on the business. The results indicate that these qualities of entrepreneur tend to be crucially important for the success of the business. The models estimated for the two DS divisional areas, Kuliyapitiya East and West, verify the importance of spatial differences. Therefore, it can be concluded that development of entrepreneurial skills of entrepreneur in small and medium industries is crucial for the success of business, when qualities of entrepreneurs are contextualized in urban settings where there is greater population density.

  18. No More Polarization, Please!

    DEFF Research Database (Denmark)

    Hansen, Mia Reinholt

    The organizational science literature on motivation has for long been polarized into two main positions; the organizational economic position focusing on extrinsic motivation and the organizational behavior position emphasizing intrinsic motivation. With the rise of the knowledge economy...... and the increasing levels of complexities it entails, such polarization is not fruitful in the attempt to explain motivation of organizational members. This paper claims that a more nuanced perspective on motivation, acknowledging the co-existence of intrinsic and extrinsic motivation, the possible interaction...... between the two as well as different types of motivations filling in the gap between the two polar types, is urgently needed in the organizational science literature. By drawing on the research on intrinsic and extrinsic motivation conducted in social psychology and combining this with contributions from...

  19. ORGANIZATIONAL CHANGE AND COMMUNICATION IN QUALITY SERVICE IMPROVEMENT FOR USERS OF THE INFORMATION TECHNOLOGY AT THE STATE SECRETARIAT OF FINANCE OF PERNAMBUCO

    Directory of Open Access Journals (Sweden)

    Clara Emilie Boeckmann

    2007-01-01

    Full Text Available The State Secretariat of Finance of Pernambuco (SEFAZ, has developed since 1997 an extensive program of modernization, mainly concerning Information Technology (IT, encompassing in its Management Model, the organizational changes that place serious challenges to the management of IT inside SEFAZ, especially regarding the users support. This work has had as main objectives, to identify and to evaluate the existing difficulties concerning IT at SEFAZ, concentrating attention on the users support, focusing the problems in the context of the organizational change and organizational communication. A questionnaire was applied to 120 employees. The results indicated positive scenes of the relation between the users and the IT structure, the satisfaction related to the majority of the evaluated items, including positive pointers of 100%. However, although 92% recognize that IT is very important in the accomplishment of their activities, 68% do not know about the modernization of the change processes, making the process of IT adaptation a difficult task. A plan of management to the users support must be elaborated, including resources that promote a new culture of internal communication and strategies of the organizational change.

  20. PROCEEDINGS OF RIKEN BNL RESEARCH CENTER WORKSHOP ON RHIC SPIN PHYSICS III AND IV, POLARIZED PARTONS AT HIGH Q2 REGION, AUGUST 3, 2000 AT BNL, OCTOBER 14, 2000 AT KYOTO UNIVERSITY.

    Energy Technology Data Exchange (ETDEWEB)

    BUNCE, G.; VIGDOR, S.

    2001-03-15

    International workshop on II Polarized Partons at High Q2 region 11 was held at the Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto, Japan on October 13-14, 2000, as a satellite of the international conference ''SPIN 2000'' (Osaka, Japan, October 16-21,2000). This workshop was supported by RIKEN (The Institute of Physical and Chemical Research) and by Yukawa Institute. The scientific program was focused on the upcoming polarized collider RHIC. The workshop was also an annual meeting of RHIC Spin Collaboration (RSC). The number of participants was 55, including 28 foreign visitors and 8 foreign-resident Japanese participants, reflecting the international nature of the RHIC spin program. At the workshop there were 25 oral presentations in four sessions, (1) RHIC Spin Commissioning, (2) Polarized Partons, Present and Future, (3) New Ideas on Polarization Phenomena, (4) Strategy for the Coming Spin Running. In (1) the successful polarized proton commissioning and the readiness of the accelerator for the physics program impressed us. In (2) and (3) active discussions were made on the new structure function to be firstly measured at RHIC, and several new theoretical ideas were presented. In session (4) we have established a plan for the beam time requirement toward the first collision of polarized protons. These proceedings include the transparencies presented at the workshop. The discussion on ''Strategy for the Coming Spin Running'' was summarized by the chairman of the session, S. Vigdor and G. Bunce.

  1. The Cool Club: Creating engaging, experimental and creative encounters between young minds and polar researchers at SPRI

    Science.gov (United States)

    Weeks, S. M.; Pope, A.

    2011-12-01

    Whilst the scientific case for current climate change is compelling, the consequences of climate change have largely failed to permeate through to individuals. This lack of public awareness of the science and the potential impacts could be considered a key obstacle to action. The possible reasons for such limited success centre on the issue that climate change is a complex subject, and that a wide ranging academic, political and social research literature on the science and wider implications of climate change has failed to communicate the key issues in an accessible way. These failures to adequately communicate both the science and the social science of climate change at a number of levels results in ';communication gaps' that act as fundamental barriers to both understanding and engagement with the issue. Meyer and Land (2003) suggest that learners can find certain ideas and concepts within a discipline difficult to understand and these act as a barrier to deeper understanding of a subject. To move beyond these threshold concepts, they suggest that the expert needs to support the learner through a range of learning experiences that allows the development of learning strategies particular to the individual. Meyer and Land's research into these threshold concepts has been situated within Economics, but has been suggested to be more widely applicable though there has been no attempt to either define or evaluate threshold concepts to climate change science. By identifying whether common threshold concepts exist specifically in climate science for cohorts of either formal or informal learners, scientists will be better able to support the public in understanding these concepts by changing how the knowledge is communicated to help overcome these barriers to learning. This paper reports on the findings of a study that examined the role of threshold concepts as barriers to understanding climate science in a UK University and considers its implications for wider

  2. Polar low monitoring

    Science.gov (United States)

    Bobylev, Leonid; Zabolotskikh, Elizaveta; Mitnik, Leonid

    2010-05-01

    Polar lows are intense mesoscale atmospheric low pressure weather systems, developing poleward of the main baroclinic zone and associated with high surface wind speeds. Small size and short lifetime, sparse in-situ observations in the regions of their development complicate polar low study. Our knowledge of polar lows and mesocyclones has come almost entirely during the period of satellite remote sensing since, by virtue of their small horizontal scale, it was rarely possible to analyse these lows on conventional weather charts using only the data from the synoptic observing network. However, the effects of intense polar lows have been felt by coastal communities and seafarers since the earliest times. These weather systems are thought to be responsible for the loss of many small vessels over the centuries, although the nature of the storms was not understood and their arrival could not be predicted. The actuality of the polar low research is stipulated by their high destructive power: they are a threat to such businesses as oil and gas exploration, fisheries and shipping. They could worsen because of global warming: a shrinking of sea ice around the North Pole, which thawed to its record minimum in the summer of 2007, is likely to give rise to more powerful storms that form only over open water and can cause hurricane-strength winds. Therefore, study of polar lows, their timely detection, tracking and forecasting represents a challenge for today meteorology. Satellite passive microwave data, starting from Special Sensor Microwave Imager (SSM/I) onboard Defense Meteorological Satellite Program (DMSP) satellite, remain invaluable source of regularly available remotely sensed data to study polar lows. The sounding in this spectral range has several advantages in comparison with observations in visible and infrared ranges and Synthetic Aperture Radar (SAR) data: independence on day time and clouds, regularity and high temporal resolution in Polar Regions. Satellite

  3. Strategic Polarization.

    Science.gov (United States)

    Kalai, Adam; Kalai, Ehud

    2001-08-01

    In joint decision making, similarly minded people may take opposite positions. Consider the example of a marriage in which one spouse gives generously to charity while the other donates nothing. Such "polarization" may misrepresent what is, in actuality, a small discrepancy in preferences. It may be that the donating spouse would like to see 10% of their combined income go to charity each year, while the apparently frugal spouse would like to see 8% donated. A simple game-theoretic analysis suggests that the spouses will end up donating 10% and 0%, respectively. By generalizing this argument to a larger class of games, we provide strategic justification for polarization in many situations such as debates, shared living accommodations, and disciplining children. In some of these examples, an arbitrarily small disagreement in preferences leads to an arbitrarily large loss in utility for all participants. Such small disagreements may also destabilize what, from game-theoretic point of view, is a very stable equilibrium. Copyright 2001 Academic Press.

  4. Research and International Trade Policy Negotiations

    International Development Research Centre (IDRC) Digital Library (Canada)

    Second, to the institutions and organizations—such as the International Development Research Centre (IDRC), the Secretariat for Science, Technology and Productive ..... A fourth challenge in the postreform period is the growing demand for participation in government activities, and for transparency in those activities.

  5. Precessing deuteron polarization

    International Nuclear Information System (INIS)

    Sitnik, I.M.; Volkov, V.I.; Kirillov, D.A.; Piskunov, N.M.; Plis, Yu.A.

    2002-01-01

    The feasibility of the acceleration in the Nuclotron of deuterons polarized in the horizontal plane is considered. This horizontal polarization is named precessing polarization. The effects of the main magnetic field and synchrotron oscillations are included. The precessing polarization is supposed to be used in studying the polarization parameters of the elastic dp back-scattering and other experiments

  6. Elite Polarization and Public Opinion

    DEFF Research Database (Denmark)

    Robison, Joshua; Mullinix, Kevin

    2016-01-01

    Elite polarization has reshaped American politics and is an increasingly salient aspect of news coverage within the United States. As a consequence, a burgeoning body of research attempts to unravel the effects of elite polarization on the mass public. However, we know very little about how...... attitudes. In our first study, we show that criticism of polarization leads partisans to more positively evaluate the argument offered by their non-preferred party, increases support for bi-partisanship, but ultimately does not change the extent to which partisans follow their party’s policy endorsements...

  7. [Consensus Statement by GeSIDA/National AIDS Plan Secretariat on antiretroviral treatment in adults infected by the human immunodeficiency virus (Updated January 2013)].

    Science.gov (United States)

    2013-11-01

    This consensus document is an update of combined antiretroviral therapy (cART) guidelines for HIV-1 infected adult patients. To formulate these recommendations a panel composed of members of the GeSIDA/National AIDS Plan Secretariat (Grupo de Estudio de Sida and the Secretaría del Plan Nacional sobre el Sida) reviewed the efficacy and safety advances in clinical trials, cohort and pharmacokinetic studies published in medical journals (PubMed and Embase) or presented in medical scientific meetings. The strength of the recommendations and the evidence which support them are based on a modification of the criteria of Infectious Diseases Society of America. cART is recommended in patients with symptoms of HIV infection, in pregnant women, in serodiscordant couples with high risk of transmission, in hepatitisB co-infection requiring treatment, and in HIV nephropathy. cART is recommended in asymptomatic patients if CD4 is 500cells/μl cART should be considered in the case of chronic hepatitisC, cirrhosis, high cardiovascular risk, plasma viral load >100.000 copies/ml, proportion of CD4 cells 55years. The objective of cART is to achieve an undetectable viral load. The first cART should include 2 reverse transcriptase inhibitors (RTI) nucleoside analogs and a third drug (a non-analog RTI, a ritonavir boosted protease inhibitor, or an integrase inhibitor). The panel has consensually selected some drug combinations, for the first cART and specific criteria for cART in acute HIV infection, in tuberculosis and other HIV related opportunistic infections, for the women and in pregnancy, in hepatitisB or C co-infection, in HIV-2 infection, and in post-exposure prophylaxis. These new guidelines update previous recommendations related to first cART (when to begin and what drugs should be used), how to monitor, and what to do in case of viral failure or adverse drug reactions. cART specific criteria in comorbid patients and special situations are similarly updated. Copyright

  8. Polare maskuliniteter

    Directory of Open Access Journals (Sweden)

    Marit Anne Hauan

    2012-05-01

    Full Text Available In this paper my aim is to read and understand the journal of Gerrit de Veer from the last journey of William Barents to the Arctic Regions in 1596 and the journal of captain Junge on his hunting trip from Tromsø to Svalbard in 1834.It is nearly 240 years between this to voyages. The first journal is known as the earliest report from the arctic era. Gerrit de Veer adds instructive copper engravings to his text and give us insight in the crews meeting with this new land. Captain Junges journal is found together with his dead crew in a house in a fjord nearby Ny-Ålesund and has no drawings, but word. Both of these journals may be read as sources of the knowledge and understanding of the polar region. They might also unveil the ideas of how to deal with and survive under the challenges that is given. In addition one can ask if the sources can tell us more about how men describe their challenges. Can the way they expressed themselves in the journals give us an understanding of masculinity? And not least help us to create good questions of the change in the ideas of masculinities which is said to follow the change in understanding of the wilderness.

  9. Polar Business Design

    Directory of Open Access Journals (Sweden)

    Sébastien Caisse

    2014-02-01

    Full Text Available Polar business design aims to enable entrepreneurs, managers, consultants, researchers, and business students to better tackle model-based analysis, creation, and transformation of businesses, ventures, and, more generically, collective endeavors of any size and purpose. It is based on a systems-thinking approach that builds on a few interrelated core concepts to create holistic visual frameworks. These core concepts act as poles linked by meaningful dyads, flows, and faces arranged in geometric shapes. The article presents two such polar frameworks as key findings in an ongoing analytic autoethnography: the three-pole Value−Activity−Stakeholder (VAS triquetra and the four-pole Offer−Creation−Character−Stakeholder (OCCS tetrahedron. The VAS triquetra is a more aggregated model of collective endeavors. The OCCS tetrahedron makes a trade-off between a steeper learning curve and deeper, richer representation potential. This article discusses how to use these two frameworks as well as their limits, and explores the potential that polar business design offers for future research.

  10. Promoting Diversity Through Polar Interdisciplinary Coordinated Education (Polar ICE)

    Science.gov (United States)

    McDonnell, J. D.; Hotaling, L. A.; Garza, C.; Van Dyk, P. B.; Hunter-thomson, K. I.; Middendorf, J.; Daniel, A.; Matsumoto, G. I.; Schofield, O.

    2017-12-01

    Polar Interdisciplinary Coordinated Education (ICE) is an education and outreach program designed to provide public access to the Antarctic and Arctic regions through polar data and interactions with the scientists. The program provides multi-faceted science communication training for early career scientists that consist of a face-to face workshop and opportunities to apply these skills. The key components of the scientist training workshop include cultural competency training, deconstructing/decoding science for non-expert audiences, the art of telling science stories, and networking with members of the education and outreach community and reflecting on communication skills. Scientists partner with educators to provide professional development for K-12 educators and support for student research symposia. Polar ICE has initiated a Polar Literacy initiative that provides both a grounding in big ideas in polar science and science communication training designed to underscore the importance of the Polar Regions to the public while promoting interdisciplinary collaborations between scientists and educators. Our ultimate objective is to promote STEM identity through professional development of scientists and educators while developing career awareness of STEM pathways in Polar science.

  11. Polarized electron sources

    Energy Technology Data Exchange (ETDEWEB)

    Prepost, R. [Univ. of Wisconsin, Madison, WI (United States)

    1994-12-01

    The fundamentals of polarized electron sources are described with particular application to the Stanford Linear Accelerator Center. The SLAC polarized electron source is based on the principle of polarized photoemission from Gallium Arsenide. Recent developments using epitaxially grown, strained Gallium Arsenide cathodes have made it possible to obtain electron polarization significantly in excess of the conventional 50% polarization limit. The basic principles for Gallium and Arsenide polarized photoemitters are reviewed, and the extension of the basic technique to strained cathode structures is described. Results from laboratory measurements of strained photocathodes as well as operational results from the SLAC polarized source are presented.

  12. Polarization and Myelination in Myelinating Glia

    Science.gov (United States)

    Masaki, Toshihiro

    2012-01-01

    Myelinating glia, oligodendrocytes in central nervous system and Schwann cells in peripheral nervous system, form myelin sheath, a multilayered membrane system around axons enabling salutatory nerve impulse conduction and maintaining axonal integrity. Myelin sheath is a polarized structure localized in the axonal side and therefore is supposed to be formed based on the preceding polarization of myelinating glia. Thus, myelination process is closely associated with polarization of myelinating glia. However, cell polarization has been less extensively studied in myelinating glia than other cell types such as epithelial cells. The ultimate goal of this paper is to provide insights for the field of myelination research by applying the information obtained in polarity study in other cell types, especially epithelial cells, to cell polarization of myelinating glia. Thus, in this paper, the main aspects of cell polarization study in general are summarized. Then, they will be compared with polarization in oligodendrocytes. Finally, the achievements obtained in polarization study for epithelial cells, oligodendrocytes, and other types of cells will be translated into polarization/myelination process by Schwann cells. Then, based on this model, the perspectives in the study of Schwann cell polarization/myelination will be discussed. PMID:23326681

  13. Geographical Income Polarization

    DEFF Research Database (Denmark)

    Azhar, Hussain; Jonassen, Anders Bruun

    inter municipal income inequality. Counter factual simulations show that rising property prices to a large part explain the rise in polarization. One side-effect of polarization is tendencies towards a parallel polarization of residence location patterns, where low skilled individuals tend to live......In this paper we estimate the degree, composition and development of geographical income polarization based on data at the individual and municipal level in Denmark from 1984 to 2002. Rising income polarization is reconfirmed when applying new polarization measures, the driving force being greater...

  14. Polarized light in optics and spectroscopy

    CERN Document Server

    Kliger, David S

    1990-01-01

    This comprehensive introduction to polarized light provides students and researchers with the background and the specialized knowledge needed to fully utilize polarized light. It provides a basic introduction to the interaction of light with matter for those unfamiliar with photochemistry and photophysics. An in-depth discussion of polarizing optics is also given. Different analytical techniques are introduced and compared and introductions to the use of polarized light in various forms of spectroscopy are provided.Key Features* Starts at a basic level and develops tools for resear

  15. Atomic processes relevant to polarization plasma spectroscopy

    International Nuclear Information System (INIS)

    Fujimoto, T.; Koike, F.; Sakimoto, K.; Okasaka, R.; Kawasaki, K.; Takiyama, K.; Oda, T.; Kato, T.

    1992-04-01

    When atoms (ions) are excited anisotropically, polarized excited atoms are produced and the radiation emitted by these atoms is polarized. From the standpoint of plasma spectroscopy research, we review the existing data for various atomic processes that are related to the polarization phenomena. These processes are: electron impact excitation, excitation by atomic and ionic collisions, photoexcitation, radiative recombination and bremsstrahlung. Collisional and radiative relaxation processes of atomic polarization follow. Other topics included are: electric-field measurement, self alignment, Lyman doublet intensity ratio, and magnetic-field measurement of the solar prominence. (author)

  16. On the identification of magnetostratigraphic polarity zones

    Czech Academy of Sciences Publication Activity Database

    Man, Otakar

    2008-01-01

    Roč. 52, č. 2 (2008), s. 173-186 ISSN 0039-3169 R&D Projects: GA ČR GA205/07/1365 Institutional research plan: CEZ:AV0Z30130516 Keywords : paleomagnetism * geomagnetic polarity reversals * magnetic polarity stratigraphy Subject RIV: DE - Earth Magnetism, Geodesy, Geography Impact factor: 0.770, year: 2008

  17. Polarized Light Corridor Demonstrations.

    Science.gov (United States)

    Davies, G. R.

    1990-01-01

    Eleven demonstrations of light polarization are presented. Each includes a brief description of the apparatus and the effect demonstrated. Illustrated are strain patterns, reflection, scattering, the Faraday Effect, interference, double refraction, the polarizing microscope, and optical activity. (CW)

  18. Polarized Moessbauer transitions

    International Nuclear Information System (INIS)

    Barb, D.

    1975-01-01

    Theoretical aspects of the emission, absorption and scattering of polarized gamma rays are reviewed for a general case of combined magnetic and electric hyperfine interactions; various possibilities of obtaining polarized gamma sources are described and examples are given of the applications of Moessbauer spectroscopy with polarized gamma rays in solving problems of solid state physics. (A.K.)

  19. Charge transport in non-polar and semi-polar III-V nitride heterostructures

    International Nuclear Information System (INIS)

    Konar, Aniruddha; Verma, Amit; Fang, Tian; Zhao, Pei; Jana, Raj; Jena, Debdeep

    2012-01-01

    Compared to the intense research focus on the optical properties, the transport properties in non-polar and semi-polar III-nitride semiconductors remain relatively unexplored to date. The purpose of this paper is to discuss charge-transport properties in non-polar and semi-polar orientations of GaN in a comparative fashion to what is known for transport in polar orientations. A comprehensive approach is adopted, starting from an investigation of the differences in the electronic bandstructure along different polar orientations of GaN. The polarization fields along various orientations are then discussed, followed by the low-field electron and hole mobilities. A number of scattering mechanisms that are specific to non-polar and semi-polar GaN heterostructures are identified, and their effects are evaluated. Many of these scattering mechanisms originate due to the coupling of polarization with disorder and defects in various incarnations depending on the crystal orientation. The effect of polarization orientation on carrier injection into quantum-well light-emitting diodes is discussed. This paper ends with a discussion of orientation-dependent high-field charge-transport properties including velocity saturation, instabilities and tunneling transport. Possible open problems and opportunities are also discussed. (paper)

  20. The Physics of Polarization

    Science.gov (United States)

    Landi Degl'Innocenti, Egidio

    2015-10-01

    The introductory lecture that has been delivered at this Symposium is a condensed version of an extended course held by the author at the XII Canary Island Winter School from November 13 to November 21, 2000. The full series of lectures can be found in Landi Degl'Innocenti (2002). The original reference is organized in 20 Sections that are here itemized: 1. Introduction, 2. Description of polarized radiation, 3. Polarization and optical devices: Jones calculus and Muller matrices, 4. The Fresnel equations, 5. Dichroism and anomalous dispersion, 6. Polarization in everyday life, 7. Polarization due to radiating charges, 8. The linear antenna, 9. Thomson scattering, 10. Rayleigh scattering, 11. A digression on Mie scattering, 12. Bremsstrahlung radiation, 13. Cyclotron radiation, 14. Synchrotron radiation, 15. Polarization in spectral lines, 16. Density matrix and atomic polarization, 17. Radiative transfer and statistical equilibrium equations, 18. The amplification condition in polarized radiative transfer, and 19. Coupling radiative transfer and statistical equilibrium equations.

  1. ECUT: Energy Conversion and Utilization Technologies program biocatalysis research activity. Potential membrane applications to biocatalyzed processes: Assessment of concentration polarization and membrane fouling

    Science.gov (United States)

    Ingham, J. D.

    1983-01-01

    Separation and purification of the products of biocatalyzed fermentation processes, such as ethanol or butanol, consumes most of the process energy required. Since membrane systems require substantially less energy for separation than most alternatives (e.g., distillation) they have been suggested for separation or concentration of fermentation products. This report is a review of the effects of concentration polarization and membrane fouling for the principal membrane processes: microfiltration, ultrafiltration, reverse osmosis, and electrodialysis including a discussion of potential problems relevant to separation of fermentation products. It was concluded that advanced membrane systems may result in significantly decreased energy consumption. However, because of the need to separate large amounts of water from much smaller amounts of product that may be more volatile than wate, it is not clear that membrane separations will necessarily be more efficient than alternative processes.

  2. PolarTREC—A Model Program for Taking Polar Literacy into the Future

    Science.gov (United States)

    Warburton, J.; Timm, K.; Larson, A. M.

    2009-12-01

    Polar TREC—Teachers and Researchers Exploring and Collaborating, is a three-year (2007-2009) NSF-funded International Polar Year (IPY) teacher professional development program that advances Science, Technology, Engineering, and Mathematics (STEM) education by improving teacher content knowledge and instructional practices through Teacher Research Experiences (TRE) in the Arctic and Antarctic. Leveraging profound changes and fascinating science taking place in the polar regions, PolarTREC broadly disseminates activities and products to students, educators, researchers, and the public, connecting them with the Arctic and Antarctica and sustaining the widespread interest in the polar regions and building on the enthusiasm that was generated through IPY. Central to the PolarTREC Teacher Research Experience Model, over 40 teachers have spent two to eight weeks participating in hands-on research in the polar regions and sharing their experiences with diverse audiences via live events, online multimedia journals, and interactive bulletin boards. The Connecting Arctic/Antarctic Researchers and Educators (CARE) Network unifies learning community members participants, alumni, and others, developing a sustainable association of education professionals networking to share and apply polar STEM content and pedagogical skills. Educator and student feedback from preliminary results of the program evaluation has shown that PolarTREC’s comprehensive program activities have many positive impacts on educators and their ability to teach science concepts and improve their teaching methods. Additionally, K-12 students polled in interest surveys showed significant changes in key areas including amount of time spent in school exploring research activities, importance of understanding science for future work, importance of understanding the polar regions as a person in today’s world, as well as increased self-reported knowledge and interest in numerous science content areas. Building

  3. [Review] Polarization and Polarimetry

    Science.gov (United States)

    Trippe, Sascha

    2014-02-01

    Polarization is a basic property of light and is fundamentally linked to the internal geometry of a source of radiation. Polarimetry complements photometric, spectroscopic, and imaging analyses of sources of radiation and has made possible multiple astrophysical discoveries. In this article I review (i) the physical basics of polarization: electromagnetic waves, photons, and parameterizations; (ii) astrophysical sources of polarization: scattering, synchrotron radiation, active media, and the Zeeman, Goldreich-Kylafis, and Hanle effects, as well as interactions between polarization and matter (like birefringence, Faraday rotation, or the Chandrasekhar-Fermi effect); (iii) observational methodology: on-sky geometry, influence of atmosphere and instrumental polarization, polarization statistics, and observational techniques for radio, optical, and X/γ wavelengths; and (iv) science cases for astronomical polarimetry: solar and stellar physics, planetary system bodies, interstellar matter, astrobiology, astronomical masers, pulsars, galactic magnetic fields, gamma-ray bursts, active galactic nuclei, and cosmic microwave background radiation.

  4. Polarization feedback laser stabilization

    Science.gov (United States)

    Esherick, P.; Owyoung, A.

    1987-09-28

    A system for locking two Nd:YAG laser oscillators includes an optical path for feeding the output of one laser into the other with different polarizations. Elliptical polarization is incorporated into the optical path so that the change in polarization that occurs when the frequencies coincide may be detected to provide a feedback signal to control one laser relative to the other. 4 figs.

  5. Polarization in Sagittarius A*

    OpenAIRE

    Bower, Geoffrey C.

    2000-01-01

    We summarize the current state of polarization observations of Sagittarius A*, the compact radio source and supermassive black hole candidate in the Galactic Center. These observations are providing new tools for understanding accretion disks, jets and their environments. Linear polarization observations have shown that Sgr A* is unpolarized at frequencies as high as 86 GHz. However, recent single-dish observations indicate that Sgr A* may have strong linear polarization at frequencies higher...

  6. Coherence and Polarization of Polarization Speckle Generated by Depolarizers and Their Changes through Complex ABCD Matrix

    DEFF Research Database (Denmark)

    Ma, Ning; Hanson, Steen Grüner; Lee, Tim K.

    2015-01-01

    Recent research work on speckle patterns indicates a variation of the polarization state during propagation and its nonuniformly spatial distribution. The preliminary step for the investigation of this polarization speckle is the generation of the corresponding field. In this paper, a kind of spe...... of coherence (DoC). and degree of polarization (DoP) P. The changes of the coherence and polarization when the speckle field propagates through any optical system are analysed within the framework of the complex ABCD-matrix theory....

  7. Airborne Laser Polarization Sensor

    Science.gov (United States)

    Kalshoven, James, Jr.; Dabney, Philip

    1991-01-01

    Instrument measures polarization characteristics of Earth at three wavelengths. Airborne Laser Polarization Sensor (ALPS) measures optical polarization characteristics of land surface. Designed to be flown at altitudes of approximately 300 m to minimize any polarizing or depolarizing effects of intervening atmosphere and to look along nadir to minimize any effects depending on look angle. Data from measurements used in conjunction with data from ground surveys and aircraft-mounted video recorders to refine mathematical models used in interpretation of higher-altitude polarimetric measurements of reflected sunlight.

  8. Polarization at SLC

    International Nuclear Information System (INIS)

    Swartz, M.L.

    1988-07-01

    The SLAC Linear Collider has been designed to readily accommodate polarized electron beams. Considerable effort has been made to implement a polarized source, a spin rotation system, and a system to monitor the beam polarization. Nearly all major components have been fabricated. At the current time, several source and polarimeter components have been installed. The installation and commissioning of the entire system will take place during available machine shutdown periods as the commissioning of SLC progresses. It is expected that a beam polarization of 45% will be achieved with no loss in luminosity. 13 refs., 15 figs

  9. Polar Balloon Experiment for Astrophysics Research (Polar BEAR)

    Science.gov (United States)

    Bashindzhagyan, G.; Adams, James H., Jr.; Bashindzhagyan, P.; Chilingarian, A.; Donnelly, J.; Drury, L.; Egorov, N.; Golubkov, S.; Grebenyuk, V.; Kalinin, A.; hide

    2001-01-01

    A new balloon experiment is proposed for a long duration flight around the North Pole. The primary objective of the experiment is to measure the elemental energy spectra of high-energy cosmic rays in the region up to 10(exp 15) eV. The proposed instrument involves the combination of a large collecting area (approximately 1 x 1 square m) KLEM (Kinematic Lightweight Energy Meter) device with an ionization calorimeter having a smaller collecting area (approximately 0.5 x 0.5 square m) and integrated beneath the KLEM apparatus. This combination has several important advantages. Due to the large aperture (greater than 2 square m sr) of the KLEM device a large exposure factor can be achieved with a long duration balloon flight (2-4 weeks). The calorimeter will collect about 10% of the events already registered by KLEM and provide effective cross-calibration for both energy measurement methods. Details of the experiment and its astrophysical significance will be presented.

  10. RHIC Polarized proton operation

    International Nuclear Information System (INIS)

    Huang, H.; Ahrens, L.; Alekseev, I.G.; Aschenauer, E.; Atoian, G.; Bai, M.; Bazilevsky, A.; Blaskiewicz, M.; Brennan, J.M.; Brown, K.A.; Bruno, D.; Connolly, R.; Dion, A.; D'Ottavio, T.; Drees, K.A.; Fischer, W.; Gardner, C.; Glenn, J.W.; Gu, X.; Harvey, M.; Hayes, T.; Hoff, L.; Hulsart, R.L.; Laster, J.; Liu, C.; Luo, Y.; MacKay, W.W.; Makdisi, Y.; Marr, G.J.; Marusic, A.; Meot, F.; Mernick, K.; Michnoff, R.; Minty, M.; Montag, C.; Morris, J.; Nemesure, S.; Poblaguev, A.; Ptitsyn, V.; Ranjibar, V.; Robert-Demolaize, G.; Roser, T.; Schmidke, B.; Schoefer, V.; Severino, F.; Smirnov, D.; Smith, K.; Steski, D.; Svirida, D.; Tepikian, S.; Trbojevic, D.; Tsoupas, N.; Tuozzolo, J.E.; Wang, G.; Wilinski, M.; Yip, K.; Zaltsman, A.; Zelenski, A.; Zeno, K.; Zhang, S.Y.

    2011-01-01

    The Relativistic Heavy Ion Collider (RHIC) operation as the polarized proton collider presents unique challenges since both luminosity(L) and spin polarization(P) are important. With longitudinally polarized beams at the experiments, the figure of merit is LP 4 . A lot of upgrades and modifications have been made since last polarized proton operation. A 9 MHz rf system is installed to improve longitudinal match at injection and to increase luminosity. The beam dump was upgraded to increase bunch intensity. A vertical survey of RHIC was performed before the run to get better magnet alignment. The orbit control is also improved this year. Additional efforts are put in to improve source polarization and AGS polarization transfer efficiency. To preserve polarization on the ramp, a new working point is chosen such that the vertical tune is near a third order resonance. The overview of the changes and the operation results are presented in this paper. Siberian snakes are essential tools to preserve polarization when accelerating polarized beams to higher energy. At the same time, the higher order resonances still can cause polarization loss. As seen in RHIC, the betatron tune has to be carefully set and maintained on the ramp and during the store to avoid polarization loss. In addition, the orbit control is also critical to preserve polarization. The higher polarization during this run comes from several improvements over last run. First we have a much better orbit on the ramp. The orbit feedback brings down the vertical rms orbit error to 0.1mm, much better than the 0.5mm last run. With correct BPM offset and vertical realignment, this rms orbit error is indeed small. Second, the jump quads in the AGS improved input polarization for RHIC. Third, the vertical tune was pushed further away from 7/10 snake resonance. The tune feedback maintained the tune at the desired value through the ramp. To calibrate the analyzing power of RHIC polarimeters at any energy above

  11. RHIC Polarized proton operation

    Energy Technology Data Exchange (ETDEWEB)

    Huang, H.; Ahrens, L.; Alekseev, I.G.; Aschenauer, E.; Atoian, G.; Bai, M.; Bazilevsky, A.; Blaskiewicz, M.; Brennan, J.M.; Brown, K.A.; Bruno, D.; Connolly, R.; Dion, A.; D' Ottavio, T.; Drees, K.A.; Fischer, W.; Gardner, C.; Glenn, J.W.; Gu, X.; Harvey, M.; Hayes, T.; Hoff, L.; Hulsart, R.L.; Laster, J.; Liu, C.; Luo, Y.; MacKay, W.W.; Makdisi, Y.; Marr, G.J.; Marusic, A.; Meot, F.; Mernick, K.; Michnoff, R,; Minty, M.; Montag, C.; Morris, J.; Nemesure, S.; Poblaguev, A.; Ptitsyn, V.; Ranjibar, V.; Robert-Demolaize, G.; Roser, T.; J.; Severino, F.; Schmidke, B.; Schoefer, V.; Severino, F.; Smirnov, D.; Smith, K.; Steski, D.; Svirida, D.; Tepikian, S.; Trbojevic, D.; Tsoupas, N.; Tuozzolo, J. Wang, G.; Wilinski, M.; Yip, K.; Zaltsman, A.; Zelenski, A.; Zeno, K.; Zhang, S.Y.

    2011-03-28

    The Relativistic Heavy Ion Collider (RHIC) operation as the polarized proton collider presents unique challenges since both luminosity(L) and spin polarization(P) are important. With longitudinally polarized beams at the experiments, the figure of merit is LP{sup 4}. A lot of upgrades and modifications have been made since last polarized proton operation. A 9 MHz rf system is installed to improve longitudinal match at injection and to increase luminosity. The beam dump was upgraded to increase bunch intensity. A vertical survey of RHIC was performed before the run to get better magnet alignment. The orbit control is also improved this year. Additional efforts are put in to improve source polarization and AGS polarization transfer efficiency. To preserve polarization on the ramp, a new working point is chosen such that the vertical tune is near a third order resonance. The overview of the changes and the operation results are presented in this paper. Siberian snakes are essential tools to preserve polarization when accelerating polarized beams to higher energy. At the same time, the higher order resonances still can cause polarization loss. As seen in RHIC, the betatron tune has to be carefully set and maintained on the ramp and during the store to avoid polarization loss. In addition, the orbit control is also critical to preserve polarization. The higher polarization during this run comes from several improvements over last run. First we have a much better orbit on the ramp. The orbit feedback brings down the vertical rms orbit error to 0.1mm, much better than the 0.5mm last run. With correct BPM offset and vertical realignment, this rms orbit error is indeed small. Second, the jump quads in the AGS improved input polarization for RHIC. Third, the vertical tune was pushed further away from 7/10 snake resonance. The tune feedback maintained the tune at the desired value through the ramp. To calibrate the analyzing power of RHIC polarimeters at any energy above

  12. Terahertz polarization imaging

    NARCIS (Netherlands)

    Van der Valk, N.C.J.; Van der Marel, W.A.M.; Planken, P.C.M.

    2005-01-01

    We present a new method to measure the polarization state of a terahertz pulse by using a modified electrooptic sampling setup. To illustrate the power of this method, we show two examples in which the knowledge of the polarization of the terahertz pulse is essential for interpreting the results:

  13. Polarized proton beams

    International Nuclear Information System (INIS)

    Roser, T.

    1995-01-01

    The acceleration of polarized proton beams in circular accelerators is complicated by the presence of numerous depolarizing spin resonances. Careful and tedious minimization of polarization loss at each of these resonances allowed acceleration of polarized proton beams up to 22 GeV. It has been the hope that Siberian Snakes, which are local spin rotators inserted into ring accelerators, would eliminate these resonances and allow acceleration of polarized beams with the same ease and efficiency that is now routine for unpolarized beams. First tests at IUCF with a full Siberian Snake showed that the spin dynamics with a Snake can be understood in detail. The author now has results of the first tests of a partial Siberian Snake at the AGS, accelerating polarized protons to an energy of about 25 GeV. These successful tests of storage and acceleration of polarized proton beams open up new possibilities such as stored polarized beams for internal target experiments and high energy polarized proton colliders

  14. Precision Polarization of Neutrons

    Science.gov (United States)

    Martin, Elise; Barron-Palos, Libertad; Couture, Aaron; Crawford, Christopher; Chupp, Tim; Danagoulian, Areg; Estes, Mary; Hona, Binita; Jones, Gordon; Klein, Andi; Penttila, Seppo; Sharma, Monisha; Wilburn, Scott

    2009-05-01

    Determining polarization of a cold neutron beam to high precision is required for the next generation neutron decay correlation experiments at the SNS, such as the proposed abBA and PANDA experiments. Precision polarimetry measurements were conducted at Los Alamos National Laboratory with the goal of determining the beam polarization to the level of 10-3 or better. The cold neutrons from FP12 were polarized using optically polarized ^3He gas as a spin filter, which has a highly spin-dependent absorption cross section. A second ^ 3He spin filter was used to analyze the neutron polarization after passing through a resonant RF spin rotator. A discussion of the experiment and results will be given.

  15. Optically polarized 3He

    Science.gov (United States)

    Gentile, T. R.; Nacher, P. J.; Saam, B.; Walker, T. G.

    2018-01-01

    This article reviews the physics and technology of producing large quantities of highly spin-polarized 3He nuclei using spin-exchange (SEOP) and metastability-exchange (MEOP) optical pumping. Both technical developments and deeper understanding of the physical processes involved have led to substantial improvements in the capabilities of both methods. For SEOP, the use of spectrally narrowed lasers and K-Rb mixtures has substantially increased the achievable polarization and polarizing rate. For MEOP nearly lossless compression allows for rapid production of polarized 3He and operation in high magnetic fields has likewise significantly increased the pressure at which this method can be performed, and revealed new phenomena. Both methods have benefitted from development of storage methods that allow for spin-relaxation times of hundreds of hours, and specialized precision methods for polarimetry. SEOP and MEOP are now widely applied for spin-polarized targets, neutron spin filters, magnetic resonance imaging, and precision measurements. PMID:29503479

  16. Optically polarized 3He

    Science.gov (United States)

    Gentile, T. R.; Nacher, P. J.; Saam, B.; Walker, T. G.

    2017-10-01

    This article reviews the physics and technology of producing large quantities of highly spin-polarized 3He nuclei using spin-exchange (SEOP) and metastability-exchange (MEOP) optical pumping. Both technical developments and deeper understanding of the physical processes involved have led to substantial improvements in the capabilities of both methods. For SEOP, the use of spectrally narrowed lasers and K-Rb mixtures has substantially increased the achievable polarization and polarizing rate. For MEOP nearly lossless compression allows for rapid production of polarized 3He and operation in high magnetic fields has likewise significantly increased the pressure at which this method can be performed, and revealed new phenomena. Both methods have benefitted from development of storage methods that allow for spin-relaxation times of hundreds of hours, and specialized precision methods for polarimetry. SEOP and MEOP are now widely applied for spin-polarized targets, neutron spin filters, magnetic resonance imaging, and precision measurements.

  17. Parallel Polarization State Generation.

    Science.gov (United States)

    She, Alan; Capasso, Federico

    2016-05-17

    The control of polarization, an essential property of light, is of wide scientific and technological interest. The general problem of generating arbitrary time-varying states of polarization (SOP) has always been mathematically formulated by a series of linear transformations, i.e. a product of matrices, imposing a serial architecture. Here we show a parallel architecture described by a sum of matrices. The theory is experimentally demonstrated by modulating spatially-separated polarization components of a laser using a digital micromirror device that are subsequently beam combined. This method greatly expands the parameter space for engineering devices that control polarization. Consequently, performance characteristics, such as speed, stability, and spectral range, are entirely dictated by the technologies of optical intensity modulation, including absorption, reflection, emission, and scattering. This opens up important prospects for polarization state generation (PSG) with unique performance characteristics with applications in spectroscopic ellipsometry, spectropolarimetry, communications, imaging, and security.

  18. Polarization and Conflict: Theoretical and Empirical Issues

    OpenAIRE

    Esteban, Joan; Schneider, Gerald

    2008-01-01

    Recent formal and statistical research in political science and economics strongly indicates that various forms of political and social polarization increase the risk of violent conflict within and between nation states. The articles collected for this issue explore this crucial relationship and provide answers to a variety of topics: First, contributors address how institutions and other contingent factors mediate the conflict potential in polarized societies. Second, this special issue comp...

  19. Exploring Science Through Polar Exploration

    Science.gov (United States)

    Pfirman, S. L.; Bell, R. E.; Zadoff, L.; Kelsey, R.

    2003-12-01

    Exploring the Poles is a First Year Seminar course taught at Barnard College, Columbia University. First Year Seminars are required of incoming students and are designed to encourage critical analysis in a small class setting with focused discussion. The class links historical polar exploration with current research in order to: introduce non-scientists to the value of environmental science through polar literature; discuss issues related to venturing into the unknown that are of relevance to any discipline: self-reliance, leadership, preparation, decisions under uncertainty; show students the human face of science; change attitudes about science and scientists; use data to engage students in exploring/understanding the environment and help them learn to draw conclusions from data; integrate research and education. These goals are met by bringing analysis of early exploration efforts together with a modern understanding of the polar environment. To date to class has followed the efforts of Nansen in the Fram, Scott and Amundsen in their race to the pole, and Shackleton's Endurance. As students read turn-of-the-century expedition journals, expedition progress is progressively revealed on an interactive map showing the environmental context. To bring the exploration process to life, students are assigned to expedition teams for specific years and the fates of the student "expeditions" are based on their own decisions. For example, in the Arctic, they navigate coastal sea ice and become frozen into the ice north of Siberia, re-creating Nansen's polar drift. Fates of the teams varied tremendously: some safely emerged at Fram Strait in 4 years, while others nearly became hopelessly lost in the Beaufort Gyre. Students thus learn about variability in the current polar environment through first hand experience, enabling them to appreciate the experiences, decisions, and, in some cases, the luck, of polar explorers. Evaluation by the Columbia Center for New Media, Teaching

  20. Polarization at the SLC

    Energy Technology Data Exchange (ETDEWEB)

    Moffeit, K.C.

    1988-10-01

    The Stanford Linear collider was designed to accommodate polarized electron beams. Longitudinally polarized electrons colliding with unpolarized positrons at a center of mass energy near the Z/sup 0/ mass can be used as novel and sensitive probes of the electroweak process. A gallium arsenide based photon emission source will provide a beam of longitudinally polarized electrons of about 45 percent polarization. A system of bend magnets and a superconducting solenoid will be used to rotate the spins so that the polarization is preserved while the 1.21 GeV electrons are stored in the damping ring. Another set of bend magnets and two superconducting solenoids orient the spin vectors so that longitudinal polarization of the electrons is achieved at the collision point with the unpolarized positrons. A system to monitor the polarization based on Moller and Compton scattering will be used. Nearly all major components have been fabricated and tested. Subsystems of the source and polarimeters have been installed, and studies are in progress. The installation and commissioning of the entire system will take place during available machine shutdown periods as the commissioning of SLC progresses. 8 refs., 16 figs., 1 tab.

  1. Polarization Properties of Laser Solitons

    Directory of Open Access Journals (Sweden)

    Pedro Rodriguez

    2017-04-01

    Full Text Available The objective of this paper is to summarize the results obtained for the state of polarization in the emission of a vertical-cavity surface-emitting laser with frequency-selective feedback added. We start our research with the single soliton; this situation presents two perpendicular main orientations, connected by a hysteresis loop. In addition, we also find the formation of a ring-shaped intensity distribution, the vortex state, that shows two homogeneous states of polarization with very close values to those found in the soliton. For both cases above, the study shows the spatially resolved value of the orientation angle. It is important to also remark the appearance of a non-negligible amount of circular light that gives vectorial character to all the different emissions investigated.

  2. Polarized atomic beams for targets

    International Nuclear Information System (INIS)

    Grueebler, W.

    1984-01-01

    The basic principle of the production of polarized atomic hydrogen and deuterium beams are reviewed. The status of the present available polarization, density and intensity are presented. The improvement of atomic beam density by cooling the hydrogen atoms to low velocity is discussed. The possible use of polarized atomic beams as targets in storage rings is shown. It is proposed that polarized atomic beams can be used to produce polarized gas targets with high polarization and greatly improved density

  3. Polarized scintillator targets

    Science.gov (United States)

    van den Brandt, B.; Bunyatova, E. I.; Hautle, P.; Konter, J. A.; Mango, S.

    2000-05-01

    The hydrogen nuclei in an organic scintillator have been polarized to more than 80% and the deuterons in its fully deuterated version to 24%. The scintillator, doped with TEMPO, has been polarized dynamically in a field of 2.5 T in a vertical dilution refrigerator in which a plastic lightguide transports the scintillation light from the sample in the mixing chamber to a photomultiplier outside the cryostat. Sizeable solid samples with acceptable optical properties and light output have been prepared and successfully operated as "live" polarized targets in nuclear physics experiments.

  4. Polarized scintillator targets

    Energy Technology Data Exchange (ETDEWEB)

    Brandt, B. van den E-mail: vandenbrandt@psi.ch; Bunyatova, E.I.; Hautle, P.; Konter, J.A.; Mango, S

    2000-05-21

    The hydrogen nuclei in an organic scintillator have been polarized to more than 80% and the deuterons in its fully deuterated version to 24%. The scintillator, doped with TEMPO, has been polarized dynamically in a field of 2.5 T in a vertical dilution refrigerator in which a plastic lightguide transports the scintillation light from the sample in the mixing chamber to a photomultiplier outside the cryostat. Sizeable solid samples with acceptable optical properties and light output have been prepared and successfully operated as 'live' polarized targets in nuclear physics experiments.

  5. Heidelberg polarized alkali source

    International Nuclear Information System (INIS)

    Kraemer, D.; Steffens, E.; Jaensch, H.; Philipps Universitaet, Marburg, Germany)

    1984-01-01

    A new atomic beam type polarized alkali ion source has been installed at Heidelberg. In order to improve the beam polarization considerably optical pumping is applied in combination with an adiabatic medium field transition which results in beams in single hyperfine sublevels. The m state population is determined by laser-induced fluorescence spectroscopy. Highly polarized beams (P/sub s/ > 0.9, s = z, zz) with intensities of 30 to 130 μA can be extracted for Li + and Na + , respectively

  6. Polarization measurement in the COMPASS polarized target

    CERN Document Server

    Kondo, K; Baum, G; Berglund, P; Doshita, N; Gautheron, F; Görtz, S; Hasegawa, T; Horikawa, N; Ishimoto, S; Iwata, T; Kisselev, Yu V; Koivuniemi, J H; Le Goff, J M; Magnon, A; Meyer, W; Reicherz, G; Matsuda, T

    2004-01-01

    Continuous wave nuclear magnetic resonance (NMR) is used to determine the target polarization in the COMPASS experiment. The system is made of the so-called Liverpool Q-meters, Yale-cards, and VME modules for data taking and system controlling. In 2001 the NMR coils were embedded in the target material, while in 2002 and 2003 the coils were mounted on the outer surface of the target cells to increase the packing factor of the material. Though the error of the measurement became larger with the outer coils than with the inner coils, we have performed stable measurements throughout the COMPASS run time for 3 years. The maximum polarization was +57% and -53% as the average in the target cells.

  7. Bringing Society to a Changing Polar Ocean: Polar Interdisciplinary Coordinated Education (ICE)

    Science.gov (United States)

    Schofield, O.

    2015-12-01

    Environmental changes in the Arctic and Antarctic appear to be accelerating and scientists are trying to understand both the patterns and the impacts of change. These changes will have profound impact on humanity and create a need for public education about these critical habitats. We have focused on a two-pronged strategy to increase public awareness as well as enable educators to discuss comfortably the implications of climate change. Our first focus is on entraining public support through the development of science documentaries about the science and people who conduct it. Antarctic Edge is a feature length award-winning documentary about climate change that has been released in May 2015 and has garnered interest in movie theatres and on social media stores (NetFlix, ITunes). This broad outreach is coupled with our group's interest assisting educators formally. The majority of current polar education is focused on direct educator engagement through personal research experiences that have impact on the participating educators' classrooms. Polar Interdisciplinary Coordinated Education (ICE) proposes to improve educator and student engagement in polar sciences through exposure to scientists and polar data. Through professional development and the creation of data tools, Polar ICE will reduce the logistical costs of bringing polar science to students in grades 6-16. We will provide opportunities to: 1) build capacity of polar scientists in communicating and engaging with diverse audiences; 2) create scalable, in-person and virtual opportunities for educators and students to engage with polar scientists and their research through data visualizations, data activities, educator workshops, webinars, and student research symposia; and 3) evaluate the outcomes of Polar ICE and contribute to our understanding of science education practices. We will use a blended learning approach to promote partnerships and cross-disciplinary sharing. This combined multi-pronged approach

  8. Semantic-enabled Spatiotemporal Web Portal for Polar Sciences

    Science.gov (United States)

    Liu, K.

    2014-12-01

    It is essential for Intergovernmental and scientists to study, monitor and analyze the geographic data in polar regions. Polarregions are likely to respond rapidly and more severely to the climate changesthan any other area on the Earth.They also have significant importance for Global warming research. The ocean water around the Antarctic and Arctic is a crucial part of the ocean's thermohaline circulation. The Polar Cyberinfrastructure Program was built to acquire, share, access, analyze the polar data for Arctic and Antarctic communities. The polar data are becoming big and bring challenges for Polar Cyberinfrastructure Program including: 1) it is difficultfor polar data users to discover most relevant data based on the understanding the behavior; 2) the quality of polar data service is essential to use the polar data, however, it varies for users in different locations and different time. The semantic enabled discovery and volunteer computing are used in the Polar Cyberinfrastructurefor tackling these challenges: 1) semantic search and knowledge reasoning to improve the discovery recall and precision of polar data; 2) volunteer computing is used to gather volunteers computing resources around the world to improve the quality evaluationaccuracy of polar data service. Keywords: Polar Science, Cyberinfrastructure, Semantic, Volunteer Computing

  9. Dynamic nuclear spin polarization

    Energy Technology Data Exchange (ETDEWEB)

    Stuhrmann, H.B. [GKSS-Forschungszentrum Geesthacht GmbH (Germany)

    1996-11-01

    Polarized neutron scattering from dynamic polarized targets has been applied to various hydrogenous materials at different laboratories. In situ structures of macromolecular components have been determined by nuclear spin contrast variation with an unprecedented precision. The experiments of selective nuclear spin depolarisation not only opened a new dimension to structural studies but also revealed phenomena related to propagation of nuclear spin polarization and the interplay of nuclear polarisation with the electronic spin system. The observation of electron spin label dependent nuclear spin polarisation domains by NMR and polarized neutron scattering opens a way to generalize the method of nuclear spin contrast variation and most importantly it avoids precontrasting by specific deuteration. It also likely might tell us more about the mechanism of dynamic nuclear spin polarisation. (author) 4 figs., refs.

  10. Time Domain Induced Polarization

    DEFF Research Database (Denmark)

    Fiandaca, Gianluca; Auken, Esben; Christiansen, Anders Vest

    2012-01-01

    Time-domain-induced polarization has significantly broadened its field of reference during the last decade, from mineral exploration to environmental geophysics, e.g., for clay and peat identification and landfill characterization. Though, insufficient modeling tools have hitherto limited the use...... of time-domaininduced polarization for wider purposes. For these reasons, a new forward code and inversion algorithm have been developed using the full-time decay of the induced polarization response, together with an accurate description of the transmitter waveform and of the receiver transfer function......%. Furthermore, the presence of low-pass filters in time-domain-induced polarization instruments affects the early times of the acquired decays (typically up to 100 ms) and has to be modeled in the forward response to avoid significant loss of resolution. The developed forward code has been implemented in a 1D...

  11. Polarized proton colliders

    International Nuclear Information System (INIS)

    Roser, T.

    1995-01-01

    High energy polarized beam collisions will open up the unique physics opportunities of studying spin effects in hard processes. This will allow the study of the spin structure of the proton and also the verification of the many well documented expectations of spin effects in perturbative QCD and parity violation in W and Z production. Proposals for polarized proton acceleration for several high energy colliders have been developed. A partial Siberian Snake in the AGS has recently been successfully tested and full Siberian Snakes, spin rotators, and polarimeters for RHIC are being developed to make the acceleration of polarized beams to 250 GeV possible. This allows for the unique possibility of colliding two 250 GeV polarized proton beams at luminosities of up to 2 x 10 32 cm -2 s -1

  12. [Consensus statement of the National AIDS Plan Secretariat, Spanish Society of Emergency Medicine and AIDS Study Group of the Spanish Society of Infectious Diseases and Clinical Microbiology on Emergency and Human Immunodeficiency Virus Infection].

    Science.gov (United States)

    2013-01-01

    Supporting non-HIV specialist professionals in the treatment of patients with urgent diseases resulting from HIV infection. These recommendations have been agreed by an expert panel from the National AIDS Plan Secretariat, the Spanish Society of Emergency Medicine, and the AIDS Study Group. A review has been made of the safety and efficacy results of clinical trials and cohort studies published in biomedical journals (PubMed and Embase) or presented at conferences. The strength of each recommendation (A, B, C) and the level of supporting evidence (I, II, III) are based on a modification of the criteria of the Infectious Diseases Society of America. The data to be collected from the emergency medical history in order to recognize the patient at risk of HIV infection were specified. It stressed the basic knowledge of ART principles and its importance in terms of decline in morbidity and mortality of HIV+ patients and referring to the HIV specialist for follow-up, where appropriate, including drug interactions. Management of different emergency situations that may occur in patients with HIV infection is also mentioned. The non-HIV specialist professional, will find the necessary tools to approach HIV patients with an emergency disease. Copyright © 2012 Elsevier España, S.L. All rights reserved.

  13. Plasma polarization spectroscopy

    International Nuclear Information System (INIS)

    Iwamae, Atsushi; Horimoto, Yasuhiro; Fujimoto, Takashi; Hasegawa, Noboru; Sukegawa, Kouta; Kawachi, Tetsuya

    2005-01-01

    The electron velocity distribution function (EVDF) in plasma can be anisotropic in laser-produced plasmas. We have developed a new technique to evaluate the polarization degree of the emission lines in the extreme vacuum ultra violet wavelength region. The polarization of the emission lines and the continuums from the lithium-like nitrogen and from helium- and hydrogen-like carbon in recombining plasma is evaluated. Particle simulation in the velocity space gives the time scale for relaxation of anisotropic EVDFs. (author)

  14. Ultracold Polar Molecules

    Science.gov (United States)

    2016-04-01

    AFRL-AFOSR-UK-TR-2016-0005 Ultracold Polar Molecules Jeremy Hutson UNIVERSITY OF DURHAM Final Report 04/01/2016 DISTRIBUTION A: Distribution approved...DATES COVERED (From - To) 15-Jan-2010 to 14-Jul-2015 4. TITLE AND SUBTITLE Final Report on Grant FA8655-10-1-3033 on Ultracold Polar Molecules 5a...formation of ultracold 87RbCs molecules in their rovibrational ground state by magnetoassociation followed by STIRAP, resulting in 14 papers acknowledging

  15. Hsp Polarization Verification

    Science.gov (United States)

    Bless, Robert

    1991-07-01

    This proposal defines the procedure for determining the instrumental polarization of the polarimetric IDT (IDT#1, POL) on the HSP. 1 of 2 unpolarized standard stars wil be observed using various filter-polarizer combinations. These observations will permit the instrumental polarization to be calibrated. The instrumental polarization must be determined to a high precision in order to vectoriallly remove it from HSP polarization observations to determine the actual astronomical polarization. Final run of proposal will look at one of 2 possible stars previously observed to get another look at the throughput. Revision History: Mark H. Slovak 8/30/88 Translated to V2 proposal instructions (RPSS V6.2) S. Laurent 1/20/89 Updated: Sally Laurent 2/24/89, 3/20/89, 4/13/89, 5/12/89 Modified: P. Stanley 1/15/90 - change to use CTA selected targets only; Fixes for aberration problem - SALM 7/30/90; Based on SV/HSP 1386. New submission changed targets and revised scheduling strategy. Revised: 26 Aug 92 J. Dolan, L. Walter, P. Reppert want to re-run the proposal (3985) one last time to bring down errors.

  16. A HYBRID APPROACH FOR POLARITY SHIFT DETECTION

    Directory of Open Access Journals (Sweden)

    Michele Mistry

    2017-07-01

    Full Text Available Now-a-days sentiment analysis has become a hot research area. With the increasing use of internet, people express their views by using social media, blogs, etc. So there is a dire need to analyze people’s opinions. Sentiment classification is the main task of sentiment analysis. But while classifying sentiments, the problem of polarity shift occurs. Polarity shift is considered as a very crucial problem. Polarity shift changes a text from positive to negative and vice versa. In this paper, a hybrid approach is proposed for polarity shift detection of negation (explicit and implicit and contrast. The hybrid approach consists of a rule-based approach for detecting explicit negation and contrast and a lexicon called SentiWordNet for detecting implicit negation. The proposed approach outperforms its baselines.

  17. Polarized Light Microscopy

    Science.gov (United States)

    Frandsen, Athela F.

    2016-01-01

    Polarized light microscopy (PLM) is a technique which employs the use of polarizing filters to obtain substantial optical property information about the material which is being observed. This information can be combined with other microscopy techniques to confirm or elucidate the identity of an unknown material, determine whether a particular contaminant is present (as with asbestos analysis), or to provide important information that can be used to refine a manufacturing or chemical process. PLM was the major microscopy technique in use for identification of materials for nearly a century since its introduction in 1834 by William Fox Talbot, as other techniques such as SEM (Scanning Electron Microscopy), FTIR (Fourier Transform Infrared spectroscopy), XPD (X-ray Powder Diffraction), and TEM (Transmission Electron Microscopy) had not yet been developed. Today, it is still the only technique approved by the Environmental Protection Agency (EPA) for asbestos analysis, and is often the technique first applied for identification of unknown materials. PLM uses different configurations in order to determine different material properties. With each configuration additional clues can be gathered, leading to a conclusion of material identity. With no polarizing filter, the microscope can be used just as a stereo optical microscope, and view qualities such as morphology, size, and number of phases. With a single polarizing filter (single polars), additional properties can be established, such as pleochroism, individual refractive indices, and dispersion staining. With two polarizing filters (crossed polars), even more can be deduced: isotropy vs. anisotropy, extinction angle, birefringence/degree of birefringence, sign of elongation, and anomalous polarization colors, among others. With the use of PLM many of these properties can be determined in a matter of seconds, even for those who are not highly trained. McCrone, a leader in the field of polarized light microscopy, often

  18. The evolution of tensor polarization

    International Nuclear Information System (INIS)

    Huang, H.; Lee, S.Y.; Ratner, L.

    1993-01-01

    By using the equation of motion for the vector polarization, the spin transfer matrix for spin tensor polarization, the spin transfer matrix for spin tensor polarization is derived. The evolution equation for the tensor polarization is studied in the presence of an isolate spin resonance and in the presence of a spin rotor, or snake

  19. PRACTICE POINTS: Provisional WHO/UNAIDS Secretariat ...

    African Journals Online (AJOL)

    [World Health Organization/UNAIDS] Geneva, October, 2000. Prophylactic treatment with cotrimoxazole can potentially enhance essential HIV care programmes in Africa by preventing several secondary bacterial and parasitic infections in people living with HIV/AIDS (PLHA). This intervention has been discussed at a ...

  20. Polarized Electrons at Jefferson Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Sinclair, C.K.

    1997-12-31

    The CEBAF accelerator at Jefferson laboratory can deliver CW electron beams to three experimental halls simultaneously. A large fraction of the approved scientific program at the lab requires polarized electron beams. Many of these experiments, both polarized and unpolarized, require high average beam current as well. Since all electrons delivered to the experimental halls originate from the same cathode, delivery of polarized beam to a single hall requires using the polarized source to deliver beam to all experiments in simultaneous operation. The polarized source effort at Jefferson Lab is directed at obtaining very long polarized source operational lifetimes at high average current and beam polarization; at developing the capability to deliver all electrons leaving the polarized source to the experimental halls; and at delivering polarized beam to multiple experimental halls simultaneously.initial operational experience with the polarized source will be presented.

  1. Polarized electrons at Jefferson laboratory

    International Nuclear Information System (INIS)

    The CEBAF accelerator at Jefferson laboratory can deliver CW electron beams to three experimental halls simultaneously. A large fraction of the approved scientific program at the lab requires polarized electron beams. Many of these experiments, both polarized and unpolarized, require high average beam current as well. Since all electrons delivered to the experimental halls originate from the same cathode, delivery of polarized beam to a single hall requires using the polarized source to deliver beam to all experiments in simultaneous operation. The polarized source effort at Jefferson Lab is directed at obtaining very long polarized source operational lifetimes at high average current and beam polarization; at developing the capability to deliver all electrons leaving the polarized source to the experimental halls; and at delivering polarized beam to multiple experimental halls simultaneously. Initial operational experience with the polarized source will be presented

  2. Polarized protons at RHIC

    International Nuclear Information System (INIS)

    Tannenbaum, M.J.

    1990-12-01

    The Physics case is presented for the use of polarized protons at RHIC for one or two months each year. This would provide a facility with polarizations of approx-gt 50% high luminosity ∼2.0 x 10 32 cm -2 s -1 , the possibility of both longitudinal and transverse polarization at the interaction regions, and frequent polarization reversal for control of systematic errors. The annual integrated luminosity for such running (∼10 6 sec per year) would be ∫ Ldt = 2 x 10 38 cm -2 -- roughly 20 times the total luminosity integrated in ∼ 10 years of operation of the CERN Collider (∼10 inverse picobarns, 10 37 cm -2 ). This facility would be unique in the ability to perform parity-violating measurements and polarization test of QCD. Also, the existence of p-p collisions in a new energy range would permit the study of ''classical'' reactions like the total cross section and elastic scattering, etc., and serve as a complement to measurements from p-bar p colliders. 11 refs

  3. The Bochum Polarized Target

    International Nuclear Information System (INIS)

    Reicherz, G.; Goertz, S.; Harmsen, J.; Heckmann, J.; Meier, A.; Meyer, W.; Radtke, E.

    2001-01-01

    The Bochum 'Polarized Target' group develops the target material 6 LiD for the COMPASS experiment at CERN. Several different materials like alcohols, alcanes and ammonia are under investigation. Solid State Targets are polarized in magnetic fields higher than B=2.5T and at temperatures below T=1K. For the Dynamic Nuclear Polarization process, paramagnetic centers are induced chemically or by irradiation with ionizing beams. The radical density is a critical factor for optimization of polarization and relaxation times at adequate magnetic fields and temperatures. In a high sensitive EPR--apparatus, an evaporator and a dilution cryostat with a continuous wave NMR--system, the materials are investigated and optimized. To improve the polarization measurement, the Liverpool NMR-box is modified by exchanging the fixed capacitor for a varicap diode which not only makes the tuning very easy but also provides a continuously tuned circuit. The dependence of the signal area upon the circuit current is measured and it is shown that it follows a linear function

  4. In-line Fiber Polarizer

    OpenAIRE

    Perumalsamy, Priya

    1998-01-01

    Polarizers and polarization devices are important components in fiber optic communication and sensor systems. There is a growing need for efficient low loss components that are compatible with optical fibers. An all fiber in-line polarizer is a more desirable alternative that could be placed at appropriate intervals along communication links. An in-line fiber polarizer was fabricated and tested. The in-line fiber polarizer operates by coupling optical energy propagatin...

  5. Electron-Spin Filters Would Offer Spin Polarization Greater than 1

    Science.gov (United States)

    Ting, David Z.

    2009-01-01

    A proposal has been made to develop devices that would generate spin-polarized electron currents characterized by polarization ratios having magnitudes in excess of 1. Heretofore, such devices (denoted, variously, as spin injectors, spin polarizers, and spin filters) have typically offered polarization ratios having magnitudes in the approximate range of 0.01 to 0.1. The proposed devices could be useful as efficient sources of spin-polarized electron currents for research on spintronics and development of practical spintronic devices.

  6. The essential features and modes of bacterial polar growth.

    Science.gov (United States)

    Cameron, Todd A; Zupan, John R; Zambryski, Patricia C

    2015-06-01

    Polar growth represents a surprising departure from the canonical dispersed cell growth model. However, we know relatively little of the underlying mechanisms governing polar growth or the requisite suite of factors that direct polar growth. Underscoring how classic doctrine can be turned on its head, the peptidoglycan layer of polar-growing bacteria features unusual crosslinks and in some species the quintessential cell division proteins FtsA and FtsZ are recruited to the growing poles. Remarkably, numerous medically important pathogens utilize polar growth, accentuating the need for intensive research in this area. Here we review models of polar growth in bacteria based on recent research in the Actinomycetales and Rhizobiales, with emphasis on Mycobacterium and Agrobacterium species. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Political Competition and Polarization

    DEFF Research Database (Denmark)

    Schultz, Christian

    This paper considers political competition and the consequences of political polarization when parties are better informed about how the economy functions than voters are. Specifically, parties know the cost producing a public good, voters do not. An incumbent's choice of policy acts like a signa...... for costs before an upcoming election. It is shown that the more polarized the political parties the more distorted the incumbent's policy choice.......This paper considers political competition and the consequences of political polarization when parties are better informed about how the economy functions than voters are. Specifically, parties know the cost producing a public good, voters do not. An incumbent's choice of policy acts like a signal...

  8. Physics of polarized targets

    CERN Document Server

    Niinikoski, Tapio

    2014-01-01

    For developing, building and operating solid polarized targets we need to understand several fields of physics that have seen sub stantial advances during the last 50 years. W e shall briefly review a selection of those that are important today. These are: 1) quantum statistical methods to describe saturation and relaxation in magnetic resonance; 2) equal spin temperature model for dy namic nuclear polarization; 3 ) weak saturation during NMR polarization measurement; 4 ) refrigeration using the quantum fluid properties of helium isotopes. These, combined with superconducting magnet technologies, permit today to reach nearly complete pola rization of almost any nuclear spins. Targets can be operated in frozen spin mode in rather low and inhomogeneous field of any orientation, and in DNP mode in beams of high intensity. Beyond such experiments of nuclear and particle physics, applications a re also emerging in macromolecular chemistry and in magnetic resonance imaging. This talk is a tribute to Michel Borghini...

  9. Polarized source upgrading

    International Nuclear Information System (INIS)

    Clegg, T.B.; Rummel, R.L.; Carter, E.P.; Westerfeldt, C.R.; Lovette, A.W.; Edwards, S.E.

    1985-01-01

    The decision was made this past year to move the Lamb-shift polarized ion source which was first installed in the laboratory in 1970. The motivation was the need to improve the flexibility of spin-axis orientation by installing the ion source with a new Wien-filter spin precessor which is capable of rotating physically about the beam axis. The move of the polarized source was accomplished in approximately two months, with the accelerator being turned off for experiments during approximately four weeks of this time. The occasion of the move provided the opportunity to rewire completely the entire polarized ion source frame and to rebuild approximately half of the electronic chassis on the source. The result is an ion source which is now logically wired and carefully documented. Beams obtained from the source are much more stable than those previously available

  10. A lunar polar expedition

    Science.gov (United States)

    Dowling, Richard; Staehle, Robert L.; Svitek, Tomas

    1992-09-01

    Advanced exploration and development in harsh environments require mastery of basic human survival skill. Expeditions into the lethal climates of Earth's polar regions offer useful lessons for tommorrow's lunar pioneers. In Arctic and Antarctic exploration, 'wintering over' was a crucial milestone. The ability to establish a supply base and survive months of polar cold and darkness made extensive travel and exploration possible. Because of the possibility of near-constant solar illumination, the lunar polar regions, unlike Earth's may offer the most hospitable site for habitation. The World Space Foundation is examining a scenario for establishing a five-person expeditionary team on the lunar north pole for one year. This paper is a status report on a point design addressing site selection, transportation, power, and life support requirements.

  11. Bringing Polar Science to the Classroom

    Science.gov (United States)

    Bruccoli, A.; Madsen, J. M.; Porter, M.

    2004-12-01

    The NSF sponsored IceCube (OPP-0236449) and Teachers Experiencing Antarctica and the Arctic (TEA) projects have developed a model for engaging K-12 teachers in a variety of scientific disciplines using polar science as a unifying theme. An intensive workshop, Science in the Ice, provided teachers with background content knowledge and seed ideas for activities aligned with national teaching standards. These activities were used to support the introduction of authentic science investigations related to current polar research in the classroom. The pilot workshop, sponsored by the NSF supported Math-Science Partnership SCALE (0227016), demonstrated the viability of this approach for involving a continuum of teachers from novice to master in a meaningful professional development model that can lead to sustainable classroom changes. This model for teacher professional development is based on the premise that the most robust educational outreach efforts involve teachers that are prepared, supported, and connected to a network of researchers and educators. This network can also serve to both stimulate interest in polar research and as a vehicle for delivering classroom materials related to the International Polar Year. An overview of Science in the Ice will be provided to show how the natural fascination with extreme environments can be used to introduce on-going research to the classroom from multiple disciplines---glaciology, geology, and astrophysics---with a common thread of polar science. The case for involving teachers now to fully capitalize on the potential of the International Polar Year, by providing professional development opportunities including field experiences with researchers, will be made.

  12. Effect of light source parameters on the polarization properties of the beam

    Science.gov (United States)

    Liu, Dan; Liu, Yan; Jiang, Hui-lin; Liu, Zhi; Zhou, Xin; Fang, Hanhan

    2013-08-01

    Polarized laser has been widely used in free space optical communication, laser radar, and laser ranging system because of its advantages of good performance in recent years. The changes of laser polarization properties in the process of transmission in atmospheric turbulence have a certain impact on the system performance. The paper research on the rule of polarization properties changes of Gauss Schell model beam in turbulent conditions. And analysis the main factors to affect the polarization properties by numerical simulation using MATLAB software tools. The factors mainly including: initial polarization, coherence coefficient, spot size and the intensity of the atmospheric turbulent. The simulation results show that, the degree of polarization will converge to the initial polarization when the beam propagation in turbulent conditions. The degrees of polarization change to different value when initial polarization of beam is different in a short distance. And, the degrees of polarization converge to the initial polarization after long distance. Beam coherence coefficient bigger, the degree of polarization and change range increases bigger. The change of polarization more slowly for spot size is bigger. The change of polarization change is faster for longer wavelength. The conclusion of the study indicated that the light source parameters effect the changes of polarization properties under turbulent conditions. The research provides theory basis for the polarization properties of the laser propagation, and it will plays a significant role in optical communication and target recognition.

  13. POLARIZED NEUTRONS IN RHIC

    Energy Technology Data Exchange (ETDEWEB)

    COURANT,E.D.

    1998-04-27

    There does not appear to be any obvious way to accelerate neutrons, polarized or otherwise, to high energies by themselves. To investigate the behavior of polarized neutrons the authors therefore have to obtain them by accelerating them as components of heavier nuclei, and then sorting out the contribution of the neutrons in the analysis of the reactions produced by the heavy ion beams. The best neutron carriers for this purpose are probably {sup 3}He nuclei and deuterons. A polarized deuteron is primarily a combination of a proton and a neutron with their spins pointing in the same direction; in the {sup 3}He nucleus the spins of the two protons are opposite and the net spin (and magnetic moment) is almost the same as that of a free neutron. Polarized ions other than protons may be accelerated, stored and collided in a ring such as RHIC provided the techniques proposed for polarized proton operation can be adapted (or replaced by other strategies) for these ions. To accelerate polarized particles in a ring, one must make provisions for overcoming the depolarizing resonances that occur at certain energies. These resonances arise when the spin tune (ratio of spin precession frequency to orbit frequency) resonates with a component present in the horizontal field. The horizontal field oscillates with the vertical motion of the particles (due to vertical focusing); its frequency spectrum is dominated by the vertical oscillation frequency and its modulation by the periodic structure of the accelerator ring. In addition, the magnet imperfections that distort the closed orbit vertically contain all integral Fourier harmonics of the orbit frequency.

  14. Advancing Environmental Prediction Capabilities for the Polar Regions and Beyond during The Year of Polar Prediction

    Science.gov (United States)

    Werner, Kirstin; Goessling, Helge; Hoke, Winfried; Kirchhoff, Katharina; Jung, Thomas

    2017-04-01

    Environmental changes in polar regions open up new opportunities for economic and societal operations such as vessel traffic related to scientific, fishery and tourism activities, and in the case of the Arctic also enhanced resource development. The availability of current and accurate weather and environmental information and forecasts will therefore play an increasingly important role in aiding risk reduction and safety management around the poles. The Year of Polar Prediction (YOPP) has been established by the World Meteorological Organization's World Weather Research Programme as the key activity of the ten-year Polar Prediction Project (PPP; see more on www.polarprediction.net). YOPP is an internationally coordinated initiative to significantly advance our environmental prediction capabilities for the polar regions and beyond, supporting improved weather and climate services. Scheduled to take place from mid-2017 to mid-2019, the YOPP core phase covers an extended period of intensive observing, modelling, prediction, verification, user-engagement and education activities in the Arctic and Antarctic, on a wide range of time scales from hours to seasons. The Year of Polar Prediction will entail periods of enhanced observational and modelling campaigns in both polar regions. With the purpose to close the gaps in the conventional polar observing systems in regions where the observation network is sparse, routine observations will be enhanced during Special Observing Periods for an extended period of time (several weeks) during YOPP. This will allow carrying out subsequent forecasting system experiments aimed at optimizing observing systems in the polar regions and providing insight into the impact of better polar observations on forecast skills in lower latitudes. With various activities and the involvement of a wide range of stakeholders, YOPP will contribute to the knowledge base needed to managing the opportunities and risks that come with polar climate change.

  15. Dark Polar Dunes

    Science.gov (United States)

    2005-01-01

    20 January 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image, acquired during northern summer in December 2004, shows dark, windblown sand dunes in the north polar region of Mars. A vast sea of sand dunes nearly surrounds the north polar cap. These landforms are located near 80.3oN, 144.1oW. Light-toned features in the image are exposures of the substrate that underlies the dune field. The image covers an area about 3 km (1.9 mi) wide and is illuminated by sunlight from the lower left.

  16. Imaging with Polarized Neutrons

    Directory of Open Access Journals (Sweden)

    Nikolay Kardjilov

    2018-01-01

    Full Text Available Owing to their zero charge, neutrons are able to pass through thick layers of matter (typically several centimeters while being sensitive to magnetic fields due to their intrinsic magnetic moment. Therefore, in addition to the conventional attenuation contrast image, the magnetic field inside and around a sample can be visualized by detecting changes of polarization in a transmitted beam. The method is based on the spatially resolved measurement of the cumulative precession angles of a collimated, polarized, monochromatic neutron beam that traverses a magnetic field or sample.

  17. The polar mesosphere

    International Nuclear Information System (INIS)

    Morris, Ray; Murphy, Damian

    2008-01-01

    The mesosphere region, which lies at the edge of space, contains the coldest layer of the Earth's atmosphere, with summer temperatures as low as minus 130 °C. In this extreme environment ice aerosol layers have appeared since the dawn of industrialization—whose existence may arguably be linked to human influence—on yet another layer of the Earth's fragile atmosphere. Ground-based and space-based experiments conducted in the Arctic and Antarctic during the International Polar Year (IPY) aim to address limitations in our knowledge and to advance our understanding of thermal and dynamical processes at play in the polar mesosphere

  18. Internal polarized targets

    Energy Technology Data Exchange (ETDEWEB)

    Kinney, E.R.; Coulter, K.; Gilman, R.; Holt, R.J.; Kowalczyk, R.S.; Napolitano, J.; Potterveld, D.H.; Young, L. (Argonne National Lab., IL (USA)); Mishnev, S.I.; Nikolenko, D.M.; Popov, S.G.; Rachek, I.A.; Temnykh, A.B.; Toporkov, D.K.; Tsentalovich, E.P.; Wojtsekhowski, B.B. (AN SSSR, Novosibirsk (USSR). Inst. Yadernoj Fiziki)

    1989-01-01

    Internal polarized targets offer a number of advantages over external targets. After a brief review of the basic motivation and principles behind internal polarized targets, the technical aspects of the atomic storage cell will be discussed in particular. Sources of depolarization and the means by which their effects can be ameliorated will be described, especially depolarization by the intense magnetic fields arising from the circulating particle beam. The experience of the Argonne Novosibirsk collaboration with the use of a storage cell in a 2 GeV electron storage ring will be the focus of this technical discussion. 17 refs., 11 figs.

  19. AGS polarized H- source

    International Nuclear Information System (INIS)

    Kponou, A.; Alessi, J.G.; Sluyters, T.

    1985-01-01

    The AGS polarized H - source is now operational. During a month-long experimental physics run in July 1984, pulses equivalent to 15 μA x 300 μs (approx. 3 x 10 10 protons) were injected into the RFQ preaccelerator. Beam polarization, measured at 200 MeV, was approx. 75%. After the run, a program to increase the H - yield of the source was begun and significant progress has been made. The H - current is now frequently 20 to 30 μA. A description of the source and some details of our operating experience are given. We also briefly describe the improvement program

  20. The physics of polarization

    Science.gov (United States)

    Landi Degl'Innocenti, Egidio

    This course is intended to give a description of the basic physical concepts which underlie the study and the interpretation of polarization phenomena. Apart from a brief historical introduction (Sect. 1), the course is organized in three parts. A first part (Sects. 2 - 6) covers the most relevant facts about the polarization phenomena that are typically encountered in laboratory applications and in everyday life. In Sect. 2, the modern description of polarization in terms of the Stokes parameters is recalled, whereas Sect. 3 is devoted to introduce the basic tools of laboratory polarimetry, such as the Jones calculus and the Mueller matrices. The polarization phenomena which are met in the reflection and refraction of a beam of radiation at the separation surface between two dielectrics, or between a dielectric and a metal, are recalled in Sect. 4. Finally, Sect. 5 gives an introduction to the phenomena of dichroism and of anomalous dispersion and Sect. 6 summarizes the polarization phenomena that are commonly encountered in everyday life. The second part of this course (Sects. 7-14) deals with the description, within the formalism of classical physics, of the spectro-polarimetric properties of the radiation emitted by accelerated charges. Such properties are derived by taking as starting point the Liénard and Wiechert equations that are recalled and discussed in Sect. 7 both in the general case and in the non-relativistic approximation. The results are developed to find the percentage polarization, the radiation diagram, the cross-section and the spectral characteristics of the radiation emitted in different phenomena particularly relevant from the astrophysical point of view. The emission of a linear antenna is derived in Sect. 8. The other Sections are devoted to Thomson scattering (Sect. 9), Rayleigh scattering (Sect. 10), Mie scattering (Sect. 11), bremsstrahlung radiation (Sect. 12), cyclotron radiation (Sect. 13), and synchrotron radiation (Sect. 14

  1. Polarized Proton Collisions at RHIC

    CERN Document Server

    Bai, Mei; Alekseev, Igor G; Alessi, James; Beebe-Wang, Joanne; Blaskiewicz, Michael; Bravar, Alessandro; Brennan, Joseph M; Bruno, Donald; Bunce, Gerry; Butler, John J; Cameron, Peter; Connolly, Roger; De Long, Joseph; Drees, Angelika; Fischer, Wolfram; Ganetis, George; Gardner, Chris J; Glenn, Joseph; Hayes, Thomas; Hseuh Hsiao Chaun; Huang, Haixin; Ingrassia, Peter; Iriso, Ubaldo; Laster, Jonathan S; Lee, Roger C; Luccio, Alfredo U; Luo, Yun; MacKay, William W; Makdisi, Yousef; Marr, Gregory J; Marusic, Al; McIntyre, Gary; Michnoff, Robert; Montag, Christoph; Morris, John; Nicoletti, Tony; Oddo, Peter; Oerter, Brian; Osamu, Jinnouchi; Pilat, Fulvia Caterina; Ptitsyn, Vadim; Roser, Thomas; Satogata, Todd; Smith, Kevin T; Svirida, Dima; Tepikian, Steven; Tomas, Rogelio; Trbojevic, Dejan; Tsoupas, Nicholaos; Tuozzolo, Joseph; Vetter, Kurt; Wilinski, Michelle; Zaltsman, Alex; Zelenski, Anatoli; Zeno, Keith; Zhang, S Y

    2005-01-01

    The Relativistic Heavy Ion Collider~(RHIC) provides not only collisions of ions but also collisions of polarized protons. In a circular accelerator, the polarization of polarized proton beam can be partially or fully lost when a spin depolarizing resonance is encountered. To preserve the beam polarization during acceleration, two full Siberian snakes were employed in RHIC to avoid depolarizing resonances. In 2003, polarized proton beams were accelerated to 100~GeV and collided in RHIC. Beams were brought into collisions with longitudinal polarization at the experiments STAR and PHENIX by using spin rotators. RHIC polarized proton run experience demonstrates that optimizing polarization transmission efficiency and improving luminosity performance are significant challenges. Currently, the luminosity lifetime in RHIC is limited by the beam-beam effect. The current state of RHIC polarized proton program, including its dedicated physics run in 2005 and efforts to optimize luminosity production in beam-beam limite...

  2. Lobbying and political polarization

    OpenAIRE

    Ursprung, Heinrich W.

    2002-01-01

    Standard spatial models of political competition give rise to equilibria in which the competing political parties or candidates converge to a common position. In this paper I show how political polarization can be generated in models that focus on the nexus between pre-election interest group lobbying and electoral competition.

  3. Fluorescence confocal polarizing microscopy

    Indian Academy of Sciences (India)

    Much of the modern understanding of orientational order in liquid crystals (LCs) is based on polarizing microscopy (PM). A PM image bears only two-dimensional (2D) information, integrating the 3D pattern of optical birefringence over the path of light. Recently, we proposed a technique to image 3D director patterns by ...

  4. Polarization of Bremsstrahlung

    International Nuclear Information System (INIS)

    Miller, J.

    1957-01-01

    The numerical results for the polarization of Bremsstrahlung are presented. The multiple scattering of electrons in the target is taken into account. The angular-and photon energy dependences are seen on the curves for an incident 25 MeV electron energy. (Author) [fr

  5. DESY: HERA polarization

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    The new HERA electron-proton collider at DESY in Hamburg achieved the first luminosity for electron-proton collisions on 19 October last year. Only one month later, on 20 November, HERA passed another important milestone with the observation of transverse electron polarization

  6. Titan Polar Landscape Evolution

    Science.gov (United States)

    Moore, Jeffrey M.

    2016-01-01

    With the ongoing Cassini-era observations and studies of Titan it is clear that the intensity and distribution of surface processes (particularly fluvial erosion by methane and Aeolian transport) has changed through time. Currently however, alternate hypotheses substantially differ among specific scenarios with respect to the effects of atmospheric evolution, seasonal changes, and endogenic processes. We have studied the evolution of Titan's polar region through a combination of analysis of imaging, elevation data, and geomorphic mapping, spatially explicit simulations of landform evolution, and quantitative comparison of the simulated landscapes with corresponding Titan morphology. We have quantitatively evaluated alternate scenarios for the landform evolution of Titan's polar terrain. The investigations have been guided by recent geomorphic mapping and topographic characterization of the polar regions that are used to frame hypotheses of process interactions, which have been evaluated using simulation modeling. Topographic information about Titan's polar region is be based on SAR-Topography and altimetry archived on PDS, SAR-based stereo radar-grammetry, radar-sounding lake depth measurements, and superposition relationships between geomorphologic map units, which we will use to create a generalized topographic map.

  7. Graphics of polar figure

    International Nuclear Information System (INIS)

    Macias B, L.R.

    1991-11-01

    The objective of this work, is that starting from a data file coming from a spectra that has been softened, and of the one that have been generated its coordinates to project it in stereographic form, to create the corresponding polar figure making use of the Cyber computer of the ININ by means of the GRAPHOS package. This work only requires a Beta, Fi and Intensity (I) enter data file. It starts of the existence of a softened spectra of which have been generated already with these data, making use of some language that in this case was FORTRAN for the Cyber computer, a program is generated supported in the Graphos package that allows starting of a reading of the Beta, Fi, I file, to generate the points in a stereographic projection and that it culminates with the graph of the corresponding polar figure. The program will request the pertinent information that is wanted to capture in the polar figure just as: date, name of the enter file, indexes of the polar figure, number of levels, radio of the stereographic projection (cms.), crystalline system to which belongs the sample, name the neuter graph file by create and to add the own general data. (Author)

  8. Research

    African Journals Online (AJOL)

    abp

    2015-09-09

    Sep 9, 2015 ... Orthopaedics and Traumatology, Faculty of Medicine, Adiyaman University, 02040 Adiyaman, Turkey,3Department of Orthopedics and. Traumatology, Umraniye Research and Education Hospital, 34899 Istanbul, Turkey, 4Department of Orthopedics and Traumatology, Umraniye. Research and Education ...

  9. Characteristics of volume polarization holography with linear polarization light

    Science.gov (United States)

    Zang, Jinliang; Wu, An'an; Liu, Ying; Wang, Jue; Lin, Xiao; Tan, Xiaodi; Shimura, Tsutomu; Kuroda, Kazuo

    2015-10-01

    Volume polarization holographic recording in phenanthrenequinone-doped poly(methyl methacrylate) (PQ-PMMA) photopolymer with linear polarized light is obtained. The characteristics of the volume polarization hologram are experimentally investigated. It is found that beyond the paraxial approximation the polarization states of the holographic reconstruction light are generally different from the signal light. Based on vector wave theoretical analyses and material properties, the special exposure condition for correctly holographic reconstruction is obtained and experimentally demonstrated.

  10. Research

    African Journals Online (AJOL)

    The research methodology module was reviewed as part of the overall revision of the undergraduate physiotherapy curriculum of ... Structuring the research methodology module using an EBP teaching framework prepares students to formulate a research question, effectively ... manage, and organise bibliographic citations.

  11. Research

    African Journals Online (AJOL)

    ebutamanya

    2015-05-13

    May 13, 2015 ... Systems (SEEDS)-INDEPTH Network Accra, Ghana, 3KEMRI/Wellcome Trust Research Programme, The Centre of Geographical Medicine Research-. Coast, Kilifi, Kenya, 4Population Health Sciences/Research Support Unit, Faculty of Health Sciences, Aga Khan University- East Africa, Nairobi,. Kenya ...

  12. Research

    African Journals Online (AJOL)

    research process, as part of which students must find and appraise evidence from research.[5] This highlights that teaching research methodology is inclined towards equipping students ... Students believed that evidence-based practice was vital, yet their understanding of the concept was restricted when compared with the.

  13. Research

    African Journals Online (AJOL)

    ebutamanya

    2015-03-02

    Mar 2, 2015 ... this program provided short-term and long-term research training to. US infectious disease fellows who would work on collaborative research projects with Kenyan trainees. Since the program began in. 1988, there have been 56 US trainees, and 13 of these continue to collaborate with Kenyan researchers.

  14. Proceedings of the workshop on polarized targets in storage rings

    International Nuclear Information System (INIS)

    Holt, R.J.

    1984-08-01

    Polarization phenomena have played an increasingly important part in the study of nuclei and nucleons in recent years. Polarization studies have been hampered by the relatively few and rather fragile polarized targets which are presently available. The concept of polarized gas targets in storage rings opens a much wider range of possibilities than is available in the external target geometry. This novel method will represent a considerable advance in nuclear physics and will continue to receive much attention in plans for future facilities. An internal, polarized-target station is being planned for the cooler ring at the Indiana University Cyclotron Facility. Internal targets are compatible with recent designs of electron accelerators proposed by the Massachusetts Institute of Technology and the Southeastern Universities Research Association. The key to nuclear-science programs based on internal targets pivots on recent developments in polarized atomic beam methods, which include the more recent laser-driven polarized targets. The workshop drew together a unique group of physicists in the fields of high-energy, nuclear and atomic physics. The meeting was organized in a manner that stimulated discussion among the 58 participants and focused on developments in polarized target technology and the underlying atomic physics. An impressive array of future possibilities for polarized targets as well as current developments in polarized target technology were discussed at the workshop. Abstracts of individual items from the workshop were prepared separately for the data base

  15. Proceedings of the workshop on polarized targets in storage rings

    Energy Technology Data Exchange (ETDEWEB)

    Holt, R.J. (ed.)

    1984-08-01

    Polarization phenomena have played an increasingly important part in the study of nuclei and nucleons in recent years. Polarization studies have been hampered by the relatively few and rather fragile polarized targets which are presently available. The concept of polarized gas targets in storage rings opens a much wider range of possibilities than is available in the external target geometry. This novel method will represent a considerable advance in nuclear physics and will continue to receive much attention in plans for future facilities. An internal, polarized-target station is being planned for the cooler ring at the Indiana University Cyclotron Facility. Internal targets are compatible with recent designs of electron accelerators proposed by the Massachusetts Institute of Technology and the Southeastern Universities Research Association. The key to nuclear-science programs based on internal targets pivots on recent developments in polarized atomic beam methods, which include the more recent laser-driven polarized targets. The workshop drew together a unique group of physicists in the fields of high-energy, nuclear and atomic physics. The meeting was organized in a manner that stimulated discussion among the 58 participants and focused on developments in polarized target technology and the underlying atomic physics. An impressive array of future possibilities for polarized targets as well as current developments in polarized target technology were discussed at the workshop. Abstracts of individual items from the workshop were prepared separately for the data base.

  16. On the large COMPASS polarized deuteron target

    Czech Academy of Sciences Publication Activity Database

    Ball, J.; Baum, G.; Doshita, N.; Finger Jr., M.; Finger, M.; Gautheron, F.; Goertz, S.; Hasegawa, T.; Heckmann, J.; Hess, C.; Horikawa, N.; Ishimoto, S.; Iwata, T.; Kisselev, Y.; Koivuniemi, J.H.; Kondo, K.; Le Goff, J.M.; Magnon, A.; Marchand, C.; Matsuda, T.; Meyer, W.; Reicherz, G.; Srnka, Aleš

    2006-01-01

    Roč. 56, Suppl. F (2006), F295-F305 ISSN 0011-4626 R&D Projects: GA MŠk ME 492 Institutional research plan: CEZ:AV0Z20650511 Keywords : COMPASS * polarized target * Dilution refrigerator Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 0.568, year: 2006

  17. Some applications of polarized inelastic neutron scattering

    Indian Academy of Sciences (India)

    A brief account of applications of polarized inelastic neutron scattering in condensed matter research is given. ... the itinerant antiferromagnet chromium we demonstrate that the dynamics of the longitudinal and transverse excitations are very different, resolving a long standing puzzle concerning the slope of their dispersion.

  18. Experiments with Fermilab polarized proton and polarized antiproton beams

    International Nuclear Information System (INIS)

    Yokosawa, A.

    1990-01-01

    We summarize activities concerning the Fermilab polarized beams. They include a brief description of the polarized-beam facility, measurements of beam polarization by polarimeters, asymmetry measurements in the π degree production at high p perpendicular and in the Λ (Σ degree), π ± , π degree production at large x F , and Δσ L (pp, bar pp) measurements. 18 refs

  19. NUCLEON POLARIZATION IN 3-BODY MODELS OF POLARIZED LI-6

    NARCIS (Netherlands)

    SCHELLINGERHOUT, NW; KOK, LP; COON, SA; ADAM, RM

    1993-01-01

    Just as He-3 --> can be approximately characterized as a polarized neutron target, polarized Li-6D has been advocated as a good isoscalar nuclear target for the extraction of the polarized gluon content of the nucleon. The original argument rests upon a presumed ''alpha + deuteron'' picture of Li-6,

  20. Geomagnetic polarity transitions

    Science.gov (United States)

    Merrill, Ronald T.; McFadden, Phillip L.

    1999-05-01

    The top of Earth's liquid outer core is nearly 2900 km beneath Earth's surface, so we will never be able to observe it directly. This hot, dense, molten iron-rich body is continuously in motion and is the source of Earth's magnetic field. One of the most dynamic manifestations at Earth's surface of this fluid body is, perhaps, a reversal of the geomagnetic field. Unfortunately, the most recent polarity transition occurred at about 780 ka, so we have never observed a transition directly. It seems that a polarity transition spans many human lifetimes, so no human will ever witness the phenomenon in its entirety. Thus we are left with the tantalizing prospect that paleomagnetic records of polarity transitions may betray some of the secrets of the deep Earth. Certainly, if there are systematics in the reversal process and they can be documented, then this will reveal substantial information about the nature of the lowermost mantle and of the outer core. Despite their slowness on a human timescale, polarity transitions occur almost instantaneously on a geological timescale. This rapidity, together with limitations in the paleomagnetic recording process, prohibits a comprehensive description of any reversal transition both now and into the foreseeable future, which limits the questions that may at this stage be sensibly asked. The natural model for the geomagnetic field is a set of spherical harmonic components, and we are not able to obtain a reliable model for even the first few harmonic terms during a transition. Nevertheless, it is possible, in principle, to make statements about the harmonic character of a geomagnetic polarity transition without having a rigorous spherical harmonic description of one. For example, harmonic descriptions of recent geomagnetic polarity transitions that are purely zonal can be ruled out (a zonal harmonic does not change along a line of latitude). Gleaning information about transitions has proven to be difficult, but it does seem

  1. EU-PolarNet: Connecting Science with Society

    Science.gov (United States)

    Biebow, N.

    2015-12-01

    The rapid changes occurring in the Polar Regions are significantly influencing global climate with consequences for global society. European and international polar research has contributed critical knowledge to identifying the processes behind these rapid changes but datasets from the Polar Regions are still insufficient to fully understand and more effectively predict the effects of change on our climate and society. This situation can only be improved by a more holistic integrated scientific approach, a higher degree of coordination of polar research and closer cooperation with all relevant actors on an international level. The objectives of EU-PolarNet are to establish an on-going dialogue between policy-makers, business and industry leaders, local communities and scientists to increase mutual understanding and identify new ways of working that will deliver economic and societal benefits. The results of this dialogue will be brought together in an Integrated European Research Programme that will be co-designed with all relevant stakeholders and coordinated with the activities of polar research nations beyond Europe. This programme will be accompanied by a feasible implementation plan to provide the Polar community with the capability to define the nature of environmental risks so that governments can design policy measures to mitigate them and businesses and other stakeholders benefit from the opportunities that are opening up in the Polar Regions.

  2. High energy physics with polarized beams and targets. [65 papers

    Energy Technology Data Exchange (ETDEWEB)

    Marshak, M L [ed.

    1976-01-01

    Sixty-six papers are presented as a report on conference sessions held from August 23-27, 1976, at Argonne National Laboratory. Topics covered include: (1) strong interactions; (2) weak and electromagnetic interactions; (3) polarized beams; and (4) polarized targets. A separate abstract was prepared for each paper for ERDA Energy Research Abstracts (ERA) and for the INIS Atomindex. (PMA)

  3. Polarized electron beams at SLAC

    International Nuclear Information System (INIS)

    Moffeit, K.C.

    1992-11-01

    SLAC has successfully accelerated high energy polarized electrons for the Stanford Linear Collider and fixed polarized nuclear target experiments. The polarized electron beams at SLAC use a gallium arsenide (GaAlAs for E-142) photon emission source to provide the beam of polarized electrons with polarization of approximately 28% (41% for E-142). While the beam emittance is reduced in the damping ring for SLC operation a system of bend magnets and superconducting solenoids preserve and orient the spin direction for maximum longitudinal polarization at the collision point. The electron polarization is monitored with a Compton scattering polarimeter, and was typically 22% at the e+e- collision point for the 1992 run. Improvements are discussed to increase the source polarization and to reduce the depolarization effects between the source and the collision point

  4. Analytical polarization calculations beyond SLIM

    International Nuclear Information System (INIS)

    Barber, D.P.

    1989-01-01

    A comparison is made between the theories of Bell and Leinaas and of Derbenev and Kondratenko for the spin polarization in electron storage rings. A calculation of polarization in HERA using the program SMILE of Mane is presented

  5. On Determinants of Political Polarization

    OpenAIRE

    Grechyna, Daryna

    2015-01-01

    Political polarization has been shown to significantly influence a country's economic performance. However, little is known about the drivers of political polarization. In this article, we aim to identify the main determinants of political polarization using Bayesian Model Averaging to overcome the problem of model uncertainty. We find that the level of trust within a country and the degree of income inequality are the most robust determinants of political polarization.

  6. THz Dynamic Nuclear Polarization NMR.

    Science.gov (United States)

    Nanni, Emilio A; Barnes, Alexander B; Griffin, Robert G; Temkin, Richard J

    2011-08-29

    Dynamic nuclear polarization (DNP) increases the sensitivity of nuclear magnetic resonance (NMR) spectroscopy by using high frequency microwaves to transfer the polarization of the electrons to the nuclear spins. The enhancement in NMR sensitivity can amount to a factor of well above 100, enabling faster data acquisition and greatly improved NMR measurements. With the increasing magnetic fields (up to 23 T) used in NMR research, the required frequency for DNP falls into the THz band (140-600 GHz). Gyrotrons have been developed to meet the demanding specifications for DNP NMR, including power levels of tens of watts; frequency stability of a few megahertz; and power stability of 1% over runs that last for several days to weeks. Continuous gyrotron frequency tuning of over 1 GHz has also been demonstrated. The complete DNP NMR system must include a low loss transmission line; an optimized antenna; and a holder for efficient coupling of the THz radiation to the sample. This paper describes the DNP NMR process and illustrates the THz systems needed for this demanding spectroscopic application. THz DNP NMR is a rapidly developing, exciting area of THz science and technology.

  7. Polarized lepton-nucleon scattering

    Energy Technology Data Exchange (ETDEWEB)

    Hughes, E. [Stanford Univ., CA (United States)

    1994-12-01

    The author provides a summary of the proposed and published statistical (systematic) uncertainties from the world experiments on nucleon spin structure function integrals. By the time these programs are complete, there will be a vast resource of data on nucleon spin structure functions. Each program has quite different experimental approaches regarding the beams, targets, and spectrometers thus ensuring systematically independent tests of the spin structure function measurements. Since the field of spin structure function measurements began, there has been a result appearing approximately every five years. With advances in polarized target technology and high polarization in virtually all of the lepton beams, results are now coming out each year; this is a true signature of the growth in the field. Hopefully, the experiments will provide a consistent picture of nucleon spin structure at their completion. In summary, there are still many open questions regarding the internal spin structure of the nucleon. Tests of QCD via the investigation of the Bjorken sum rule is a prime motivator for the field, and will continue with the next round of precision experiments. The question of the origin of spin is still a fundamental problem. Researchers hope is that high-energy probes using spin will shed light on this intriguing mystery, in addition to characterizing the spin structure of the nucleon.

  8. Polarized electrogowdy spacetimes censored

    Energy Technology Data Exchange (ETDEWEB)

    Nungesser, Ernesto, E-mail: ernesto.nungesser@aei.mpg.d [Max-Planck-Institut fuer Gravitationsphysik, Albert-Einstein-Institut, Am Muehlenberg 1, 14476 Potsdam (Germany)

    2010-05-01

    A sketch of the proof of strong cosmic censorship is presented for a class of solutions of the Einstein-Maxwell equations, those with polarized Gowdy symmetry. A key element of the argument is the observation that by means of a suitable choice of variables the central equations in this problem can be written in a form where they are identical to the central equations for general (i.e. non-polarized) vacuum Gowdy spacetimes. Using this it is seen that the results of Ringstroem on strong cosmic censorship in the vacuum case have implications for the Einstein-Maxwell case. Working out the geometrical meaning of these analytical results leads to the main conclusion.

  9. The polarizing effect of arousal on negotiation.

    Science.gov (United States)

    Brown, Ashley D; Curhan, Jared R

    2013-10-01

    In this research, we examined the impact of physiological arousal on negotiation outcomes. Conventional wisdom and the prescriptive literature suggest that arousal should be minimized given its negative effect on negotiations, whereas prior research on misattribution of arousal suggests that arousal might polarize outcomes, either negatively or positively. In two experiments, we manipulated arousal and measured its effect on subjective and objective negotiation outcomes. Our results support the polarization effect. When participants had negative prior attitudes toward negotiation, arousal had a detrimental effect on outcomes, whereas when participants had positive prior attitudes toward negotiation, arousal had a beneficial effect on outcomes. These effects occurred because of the construal of arousal as negative or positive affect, respectively. Our findings have important implications not only for negotiation, but also for research on misattribution of arousal, which previously has focused on the target of evaluation, in contrast to the current research, which focused on the critical role of the perceiver.

  10. PEPPo: Using a Polarized Electron Beam to Produce Polarized Positrons

    Energy Technology Data Exchange (ETDEWEB)

    Adeyemi, Adeleke H. [Hampton Univ., Hampton, VA (United States); et al.

    2015-09-01

    Polarized positron beams have been identified as either an essential or a significant ingredient for the experimental program of both the present and next generation of lepton accelerators (JLab, Super KEK B, ILC, CLIC). An experiment demonstrating a new method for producing polarized positrons has been performed at the Continuous Electron Beam Accelerator Facility at Jefferson Lab. The PEPPo (Polarized Electrons for Polarized Positrons) concept relies on the production of polarized e⁻/e⁺ pairs from the bremsstrahlung radiation of a longitudinally polarized electron beam interacting within a high-Z conversion target. PEPPo demonstrated the effective transfer of spin-polarization of an 8.2 MeV/c polarized (P~85%) electron beam to positrons produced in varying thickness tungsten production targets, and collected and measured in the range of 3.1 to 6.2 MeV/c. In comparison to other methods this technique reveals a new pathway for producing either high-energy or thermal polarized positron beams using a relatively low polarized electron beam energy (~10MeV) .This presentation will describe the PEPPo concept, the motivations of the experiment and high positron polarization achieved.

  11. Polarization induced doped transistor

    Science.gov (United States)

    Xing, Huili; Jena, Debdeep; Nomoto, Kazuki; Song, Bo; Zhu, Mingda; Hu, Zongyang

    2016-06-07

    A nitride-based field effect transistor (FET) comprises a compositionally graded and polarization induced doped p-layer underlying at least one gate contact and a compositionally graded and doped n-channel underlying a source contact. The n-channel is converted from the p-layer to the n-channel by ion implantation, a buffer underlies the doped p-layer and the n-channel, and a drain underlies the buffer.

  12. Polar bears, Ursus maritimus

    Science.gov (United States)

    Rode, Karyn D.; Stirling, Ian

    2017-01-01

    Polar bears are the largest of the eight species of bears found worldwide and are covered in a pigment-free fur giving them the appearance of being white. They are the most carnivorous of bear species consuming a high-fat diet, primarily of ice-associated seals and other marine mammals. They range throughout the circumpolar Arctic to the southernmost extent of seasonal pack ice.

  13. Polarized advanced fuel reactors

    International Nuclear Information System (INIS)

    Kulsrud, R.M.

    1987-07-01

    The d- 3 He reaction has the same spin dependence as the d-t reaction. It produces no neutrons, so that if the d-d reactivity could be reduced, it would lead to a neutron-lean reactor. The current understanding of the possible suppression of the d-d reactivity by spin polarization is discussed. The question as to whether a suppression is possible is still unresolved. Other advanced fuel reactions are briefly discussed. 11 refs

  14. On polarization in biomembranes

    DEFF Research Database (Denmark)

    Zecchi, Karis Amata

    close to physiological conditions, making these effects biologically relevant. In this work, we consider the case of asymmetric membranes which can display spontaneous polarization in the absence of a field. Close to the phase transition, we find that the membrane displays piezoelectric, flexoelectric...... on different geometries point in the direction of a flexoelectric mechanism behind current rectification in lipid bilayers. Finally, we suggest that our updated equivalent circuit should be included in the interpretation of elctrophysiological data....

  15. Multifrequency Behaviour of Polars

    Directory of Open Access Journals (Sweden)

    K. Reinsch

    2015-02-01

    Full Text Available Cataclysmic variables emit over a wide range of the electromagnetic spectrum. In this paper I will review observations of polars in relevant passbands obtained during the last decade and will discuss their diagnostical potential to access the physics of the main components within the binary systems. This will include a discussion of intrinsic source variability and the quest for simultaneous multi-frequency observations.

  16. Research

    African Journals Online (AJOL)

    abp

    2015-01-19

    Jan 19, 2015 ... in Cameroon. This study aimed at examining the sexual risk behaviours of high school female learners in Mbonge subdivision of rural Cameroon. ... Despite a wealth of research on youth, little research has been done on the sexual ..... Behavior, and Mental Health: a study of University Students in. Uganda.

  17. researchers

    African Journals Online (AJOL)

    African Sociological Review, 7, (2), 2003, pp.149-161. RESEARCH REPORTS. Revisiting “insiders' and 'outsiders' as social researchers. Marlize Rabe .... use of knowledgeable fieldworkers is then examined by focussing on the work ... A study by Russell (1995:p.95–97) on the long-term effects of incestuous abuse.

  18. Research

    African Journals Online (AJOL)

    2014-05-06

    May 6, 2014 ... facilitate and support articulation between the ECT mid-level worker qualification and the professional B EMC degree. Methods. The researchers used an exploratory, sequential mixed-method design, which is characterised by a qualitative phase of research followed by a quantitative phase. This design is ...

  19. Research

    African Journals Online (AJOL)

    In-depth telephonic interviews were voice recorded and transcribed. Through an inductive ... Two research assistants conducted the research to ..... Assistant Nutritionist. 1.25. M. 30.5. Single. BSc Food Science and Technology. Dietitian. 6. M. 25.6. Single. BSc Human Nutrition and Dietetics. Dietitian. 1. M. 29.6. Single.

  20. Optically pumped polarized 23Na vapor target for use in polarized ion source. Technical progress report

    International Nuclear Information System (INIS)

    Anderson, L.W.

    1984-01-01

    We are currently measuring relaxation times in an optically pumped 23 Na vapor target. Our research is directed toward improvements in the optically pumped Na vapor targets used for the production of polarized H - ions. In this progress report we review the properties of the optically pumped polarized H - ion source and especially the optically pumped Na vapor target employed in this source as well as discussing the progress of our research on relaxation times in an optically pumped Na vapor target. 30 references, 6 figures, 3 tables

  1. Research

    African Journals Online (AJOL)

    abp

    Research Team in Maternal and Child Health and Nutrition, Mohammed V. University, Rabat, Morocco. Key words: Breast cancer, risk factor, case-control study. Received: 04/01/2016 - Accepted: 17/03/2016 - Published: 06/05/2016. Abstract.

  2. Research

    Science.gov (United States)

    Mathematics Teaching, 1973

    1973-01-01

    Implications for teachers from Piagetian-oriented piagetian-oriented research on problem solving reported in an article by Eleanor Duckworth are presented. Edward de Bono's Children Solve Problems,'' a collection of examples, is also discussed. (MS)

  3. Research

    African Journals Online (AJOL)

    their academic performance, capabilities and functionings. At a tertiary educational level ... Research indicates that academic stressors, living circumstances, working conditions and where students undertake leisure activities affect academic performance .... Insufficient sleep, mild exhaustion, poor eating habits and little ...

  4. Research

    International Nuclear Information System (INIS)

    1999-01-01

    Subjects covered in this section are: (1) PCAST panel promotes energy research cooperation; (2) Letter issued by ANS urges funding balance in FFTF restart consideration and (3) FESAC panel releases report on priorities and balance

  5. Polar energy resources potential. Report prepared for the Committee on Science and Technology, U. S. House of Representatives, Ninety-Fourth Congress, Second Session by the Congressional Research Service, Library of Congress

    Energy Technology Data Exchange (ETDEWEB)

    1976-01-01

    The study covers both Antarctic and Arctic energy resources including oil, coal, natural gas, hydroelectric power, geothermal energy, oil shale, uranium, solar energy, and wind power. The environment, geology, topography, climate, and weather are also treated. Consideration is given to the international relations involved in energy resource exploitation in both polar regions, and the technologies necessary to develop polar resources are discussed. The potential resources in each area are described. Resource potentials south of 60 degrees in Antartica and north of 60 degrees in the Arctic are summarized. (MCW)

  6. Frequency and Polarization Diversity Jamming of Communications in Urban Environments

    National Research Council Canada - National Science Library

    Ulama, Tuncay

    2005-01-01

    The purpose of this research is to investigate how to exploit frequency and polarization techniques in reducing the effects of jamming against UAV relay communication links in an urban warfare environment...

  7. Circularly polarized antennas

    CERN Document Server

    Gao, Steven; Zhu, Fuguo

    2013-01-01

    This book presents a comprehensive insight into the design techniques for different types of CP antenna elements and arrays In this book, the authors address a broad range of topics on circularly polarized (CP) antennas. Firstly, it introduces to the reader basic principles, design techniques and characteristics of various types of CP antennas, such as CP patch antennas, CP helix antennas, quadrifilar helix antennas (QHA), printed quadrifilar helix antennas (PQHA), spiral antenna, CP slot antennas, CP dielectric resonator antennas, loop antennas, crossed dipoles, monopoles and CP horns. Adva

  8. Plasma polarization spectroscopy

    CERN Document Server

    Iwamae, Atsushi

    2008-01-01

    Plasma Polarization Spectroscopy (PPS) is now becoming a standard diagnostic technique for working with laboratory plasmas. This new area needs a comprehensive framework, both experimental and theoretical. This book reviews the historical development of PPS, develops a general theoretical formulation to deal with this phenomenon, along with an overview of relevant cross sections, and reports on laboratory experiments so far performed. It also includes various facets that are interesting from this standpoint, e.g. X-ray lasers and effects of microwave irradiation. It also offers a timely discussion of instrumentation that is quite important in a practical PPS experiment.

  9. System for measuring the proton polarization in a polarized target

    International Nuclear Information System (INIS)

    Karnaukhov, I.M.; Lukhanin, A.A.; Telegin, Yu.N.; Trotsenko, V.I.; Chechetenko, V.F.

    1984-01-01

    The system for measuring the proton polarization in a polarized target representing the high-sensitivity nuclear magnetic resonance (NMR) is described Q-meter with series connection and a circuit for measuring system resonance characteristic is used for NMR-absorption signal recording. Measuring coil is produced of a strip conductor in order to obtain uniform system sensitivity to polarization state in all target volume and improve signal-to-noise ratio. Polarization measuring system operates ion-line with the M-6000 computer. The total measuring error for the value of free proton polarization in target taking into account the error caused by local depolarization of working substance under irradiation by high-intense photon beam is <= 6%. Long-term application of the described system for measuring the proton polarization in the LUEh-20000 accelerator target used in the pion photoproduction experiments has demonstrated its high reliability

  10. A circumpolar monitoring framework for polar bears

    Science.gov (United States)

    Vongraven, Dag; Aars, Jon; Amstrup, Steven C.; Atkinson, Stephen N.; Belikov, Stanislav; Born, Erik W.; DeBruyn, T.D.; Derocher, Andrew E.; Durner, George M.; Gill, Michael J.; Lunn, Nicholas J.; Obbard, Martyn E.; Omelak, Jack; Ovsyanikov, Nikita; Peacock, Elizabeth; Richardson, E.E.; Sahanatien, Vicki; Stirling, Ian; Wiig, Øystein

    2012-01-01

    Polar bears (Ursus maritimus) occupy remote regions that are characterized by harsh weather and limited access. Polar bear populations can only persist where temporal and spatial availability of sea ice provides adequate access to their marine mammal prey. Observed declines in sea ice availability will continue as long as greenhouse gas concentrations rise. At the same time, human intrusion and pollution levels in the Arctic are expected to increase. A circumpolar understanding of the cumulative impacts of current and future stressors is lacking, long-term trends are known from only a few subpopulations, and there is no globally coordinated effort to monitor effects of stressors. Here, we describe a framework for an integrated circumpolar monitoring plan to detect ongoing patterns, predict future trends, and identify the most vulnerable polar bear subpopulations. We recommend strategies for monitoring subpopulation abundance and trends, reproduction, survival, ecosystem change, human-caused mortality, human–bear conflict, prey availability, health, stature, distribution, behavioral change, and the effects that monitoring itself may have on polar bears. We assign monitoring intensity for each subpopulation through adaptive assessment of the quality of existing baseline data and research accessibility. A global perspective is achieved by recommending high intensity monitoring for at least one subpopulation in each of four major polar bear ecoregions. Collection of data on harvest, where it occurs, and remote sensing of habitat, should occur with the same intensity for all subpopulations. We outline how local traditional knowledge may most effectively be combined with the best scientific methods to provide comparable and complementary lines of evidence. We also outline how previously collected intensive monitoring data may be sub-sampled to guide future sampling frequencies and develop indirect estimates or indices of subpopulation status. Adoption of this framework

  11. Report of the workshop on nuclear polarization phenomena

    International Nuclear Information System (INIS)

    1985-01-01

    The third work shop on the study of the nuclear polarization was held in December 1984 at RCNP (Research Center for Nuclear Physics). Osaka University, in advance of the comming international conference. About 80 researchers gathered and discussed both theoretical and experimental aspects of nuclear polarization phenomena. Forty eight papers were presented at the work shop and they are collected in this report. Although almost all of them are written in Japanese, the abstracts are prepared in English. (Aoki, K.)

  12. Research

    African Journals Online (AJOL)

    ebutamanya

    2016-03-24

    Mar 24, 2016 ... national non-governmental organization (NGO) ”Arc en Ciel„. This. NGO, which is familiar with research activities, identified the MSM community leaders in the .... whom there is an emotional attachment) in both homosexual and heterosexual populations [14, 19]. Like other reports from. Cameroon [19] and ...

  13. Research

    African Journals Online (AJOL)

    raoul

    2012-01-11

    Jan 11, 2012 ... 1MPH Programme, Department of Community Medicine, University of Zimbabwe, Zimbabwe, 2Department of Epidemiology and Disease Control,. Ministry ... Pan African Medical Journal. 2012; 11: ..... Mufuta Tshimanga: Had oversight of all the stages of the research and critically reviewed the final draft for.

  14. Research

    African Journals Online (AJOL)

    raoul

    2011-08-25

    Aug 25, 2011 ... euthanasia were also queried. Data was analyzed using Epidata, SPSS 16.0 and Microsoft Excel. Results: Thirty-eight (97.4%) of thirty-nine institutions reported using animals for education and/or research. Thirty (76.9%) institutions reported using analgesics or anesthetics on a regular basis. Thirteen ...

  15. Research

    African Journals Online (AJOL)

    abp

    2016-02-01

    Feb 1, 2016 ... University Hospital, DK-5000 Odense, Denmark, 3Center for Global Health, Institute of Clinical Research, University of Southern Denmark, DK-5000. Odense .... BHP is a Danish-Guinean Demographic Surveillance Site with a study-area .... variables such as age groups, previous military duty, history of.

  16. Research

    African Journals Online (AJOL)

    Research. May 2016, Vol. 8, No. 1 AJHPE 37. Students who enrol in occupational therapy (OT) at the. University of Kwa Zulu-Natal (UKZN), Durban, South Africa ... The latter may include becoming familiar with the disintegrating social systems in primary .... They also lacked the skills needed to adapt sessions and failed to ...

  17. Research

    African Journals Online (AJOL)

    raoul

    2011-12-14

    Dec 14, 2011 ... skills through hands-on application of epidemiology to real public health issues. For the most part, residents carry out research projects in priority areas of the districts they are attached, often under direct supervision of the local or provincial health leaders [2]. In Africa, these programs formed a networking ...

  18. Research

    African Journals Online (AJOL)

    abp

    2014-03-21

    Mar 21, 2014 ... Published in partnership with the African Field Epidemiology Network (AFENET). (www.afenet.net). Research ... were intervention strategies for primary health care delivery at the district and community levels ..... to be a gap between policy formation and implementation as only immunization services are.

  19. Research

    African Journals Online (AJOL)

    abp

    2013-03-05

    Mar 5, 2013 ... food market) [10]. There are few studies that provide data on NCDs from Africa and these are mainly from South Africa [11]. In the same vein, research efforts in The .... males, in view of the relationships between obesity, physical inactivity and .... pronged intervention strategies-epidemiological surveillance,.

  20. Research

    African Journals Online (AJOL)

    ebutamanya

    2015-11-23

    Nov 23, 2015 ... 1Amref Health Africa, P.O Box 2773 Dar es Salaam, Tanzania, 2Kilimanjaro Reproductive Health Program, Moshi, Tanzania, 3Population Services. International, Nairobi .... testing, HIV testing history and HIV test results. ..... due to differences in the research designs, nature of population and sample size ...

  1. Research

    African Journals Online (AJOL)

    ebutamanya

    2015-06-22

    Jun 22, 2015 ... collaboration with Makerere University, School of Public Health. We acknowledge The Family Health Research and Development Centre. (FHRDC) Uganda. Supported by Bill & Melinda Gates Institute for. Population & Reproductive Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, ...

  2. Research

    African Journals Online (AJOL)

    abp

    2016-04-14

    Apr 14, 2016 ... Methods. Study design: A mixed method cross-sectional design using both quantitative and qualitative research methods as described by. Hanson et al [33] was employed. Settings: The study was based on data from the midterm evaluation that was conducted between August-December 2012 involving ...

  3. Research

    African Journals Online (AJOL)

    The study followed a qualitative research design using semi-structured interviews with full-time SA- or foreign-qualified specialists at. Kimberley Hospital ... average number of weekly hours spent on undergraduate student training ... The best place to learn is at the bedside; a student should see the patient, read up and ...

  4. Research

    African Journals Online (AJOL)

    the importance of the learning setting (curriculum context), a capability approach to learning (the process), and the production of expert generalists. (the outcome) .... including communication, learning transfer, teamwork, self-confidence, and reciprocal and effective practice.[6-8] Research also shows that PAL provides a.

  5. Research

    African Journals Online (AJOL)

    raoul

    2011-11-14

    Nov 14, 2011 ... Data were collected between February and March 2010 using a questionnaire, designed by the researcher. It comprised two sections; the ..... Bazant ES, Koenig MA, Fotso J-C, Mills S. Women's Use of Private and Government Health Facilities for Childbirth in Nairobi's Informal. Settlements. Stud Fam Plann ...

  6. Research

    African Journals Online (AJOL)

    Research. This article provides a detailed description of the development of an evaluation matrix that represents the organising structure for evaluating the impact of the interdisciplinary health-promotion course on multiple stakeholders. The evaluation was designed to answer the questions relating to the perceptions and ...

  7. Research

    African Journals Online (AJOL)

    2017-03-18

    Mar 18, 2017 ... promote CPD by working in partnership with employers, academic institutions ... SORK, employers and institutions of higher education all have a responsibility towards the culture of lifelong learning. As the ... further approved by the Higher Degrees and Research Ethics Committees of the University of ...

  8. Research

    African Journals Online (AJOL)

    abp

    2014-08-29

    Aug 29, 2014 ... Page number not for citation purposes ... Pan African Medical Journal – ISSN: 1937- 8688 (www.panafrican-med-journal.com). Published in partnership with the African Field Epidemiology Network (AFENET). (www.afenet.net). Research .... and education, hence a higher risk of morbidity and mortality and a.

  9. Research

    African Journals Online (AJOL)

    tions as their reality.[14]. Research context. At Stellenbosch University (SU), Cape Town,. SA, final-year physiotherapy students each spend. 6 weeks at a community site learning to integrate and apply the principles of PHC and community- based rehabilitation. Approximately 5 - 10 clients are seen in their homes per week.

  10. Research

    African Journals Online (AJOL)

    the classroom.[9] Cognitive learning is achieved when students can make connections among and interpret different aspects of a subject to apply what they have learned in other fields of ... the effect of the field trips on the students' perceptions. ... researcher in higher education teaching and learning facilitated the data-.

  11. Research

    African Journals Online (AJOL)

    ebutamanya

    2015-12-02

    Dec 2, 2015 ... It is an important aspect of quality of life which is often neglected by people in this age group, attending physicians and the society as a whole. The study was aimed at determining ... or a trained research assistant for those who could neither read nor write. Consenting individuals above this age who have ...

  12. Research

    African Journals Online (AJOL)

    abp

    2014-01-31

    Jan 31, 2014 ... by Hazarika in a population-based study in India. The researcher noted that patients' preference to the private health facilities was due mainly to their dissatisfaction with the services in the public health facilities [11]. Furthermore, the quality of the services in the private health facilities could also be a major ...

  13. Research

    African Journals Online (AJOL)

    abp

    2017-11-30

    Nov 30, 2017 ... Authors' contributions. All the authors have read and agreed to the final manuscript. Acknowledgments. The author was supported by a postdoctoral fellowship awarded by the South African National Research Foundation (NRF). The content of this manuscript does not necessarily represent the official views.

  14. Research

    African Journals Online (AJOL)

    abp

    2017-12-05

    Dec 5, 2017 ... work is properly cited. Pan African Medical Journal – ISSN: 1937- 8688 ... an unfinished business as dozens of studies reveal millions of children worldwide have not yet benefited from the .... regions included in the research site [24]. Results. In the final analysis, three working themes were generated.

  15. Research

    African Journals Online (AJOL)

    Workshop on {topic}; research project; clinical practical experience. Outputs. Tangible products/by-products of activities (but not whether students learned anything). Certificates of completion; records of actions by participants (i.e. log books); number of students at clinical site. Intermediate outcomes Learning connected to ...

  16. Research

    African Journals Online (AJOL)

    abp

    2017-05-18

    May 18, 2017 ... available to populations of developing countries [2-5]. In 2013, in. Western and Central Europe and ..... initiation among the infected persons in the community. Addressing stigma and educating ... Lifespan/Tufts/Brown Center for AIDS Research (P30AI042853). Tables. Table 1: Baseline characteristics of ...

  17. Research

    African Journals Online (AJOL)

    2014-05-18

    May 18, 2014 ... Research. Practice within the clinical arena is recognised as the best means of socialising students into the physiotherapy profession[1-5] and is known to ..... A ect. Intervention. Overall preparedness. Fig. 1. Means and 95% CIs of the mean scores of each component (n=58; 9 missing). There is a significant ...

  18. Research

    African Journals Online (AJOL)

    YouTube, TED and other podcast websites. Other researchers have also documented their procedures. Corl et al.[5] describe the basic process of producing a podcast, and Jham et al.[6] list a number of universities actively doing podcasts. Besides the lecture podcasts, we have also captured numerous clinical.

  19. Polar drive on OMEGA

    Directory of Open Access Journals (Sweden)

    Radha P.B.

    2013-11-01

    Full Text Available High-convergence polar-drive experiments are being conducted on OMEGA [T. R. Boehly et al., Opt. Commum. 133, 495 (1997] using triple-picket laser pulses. The goal of OMEGA experiments is to validate modeling of oblique laser deposition, heat conduction in the presence of nonradial thermal gradients in the corona, and implosion energetics in the presence of laser–plasma interactions such as crossed-beam energy transfer. Simulated shock velocities near the equator, where the beams are obliquely incident, are within 5% of experimentally inferred values in warm plastic shells, well within the required accuracy for ignition. High, near-one-dimensional areal density is obtained in warm-plastic-shell implosions. Simulated backlit images of the compressing core are in good agreement with measured images. Outstanding questions that will be addressed in the future relate to the role of cross-beam transfer in polar drive irradiation and increasing the energy coupled into the target by decreasing beam obliquity.

  20. Polarized proton collider at RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Alekseev, I.; Allgower, C.; Bai, M.; Batygin, Y.; Bozano, L.; Brown, K.; Bunce, G.; Cameron, P.; Courant, E.; Erin, S.; Escallier, J.; Fischer, W.; Gupta, R.; Hatanaka, K.; Huang, H.; Imai, K.; Ishihara, M.; Jain, A.; Lehrach, A.; Kanavets, V.; Katayama, T.; Kawaguchi, T.; Kelly, E.; Kurita, K.; Lee, S.Y.; Luccio, A.; MacKay, W.W. E-mail: mackay@bnl.govhttp://www.rhichome.bnl.gov/People/waldowaldo@bnl.gov; Mahler, G.; Makdisi, Y.; Mariam, F.; McGahern, W.; Morgan, G.; Muratore, J.; Okamura, M.; Peggs, S.; Pilat, F.; Ptitsin, V.; Ratner, L.; Roser, T.; Saito, N.; Satoh, H.; Shatunov, Y.; Spinka, H.; Syphers, M.; Tepikian, S.; Tominaka, T.; Tsoupas, N.; Underwood, D.; Vasiliev, A.; Wanderer, P.; Willen, E.; Wu, H.; Yokosawa, A.; Zelenski, A.N

    2003-03-01

    In addition to heavy ion collisions (RHIC Design Manual, Brookhaven National Laboratory), RHIC will also collide intense beams of polarized protons (I. Alekseev, et al., Design Manual Polarized Proton Collider at RHIC, Brookhaven National Laboratory, 1998, reaching transverse energies where the protons scatter as beams of polarized quarks and gluons. The study of high energy polarized protons beams has been a long term part of the program at BNL with the development of polarized beams in the Booster and AGS rings for fixed target experiments. We have extended this capability to the RHIC machine. In this paper we describe the design and methods for achieving collisions of both longitudinal and transverse polarized protons in RHIC at energies up to {radical}s=500 GeV.

  1. Spin exchange in polarized deuterium

    International Nuclear Information System (INIS)

    Przewoski, B. von; Meyer, H.O.; Balewski, J.; Doskow, J.; Ibald, R.; Pollock, R.E.; Rinckel, T.; Wellinghausen, A.; Whitaker, T.J.; Daehnick, W.W.; Haeberli, W.; Schwartz, B.; Wise, T.; Lorentz, B.; Rathmann, F.; Pancella, P.V.; Saha, Swapan K.; Thoerngren-Engblom, P.

    2003-01-01

    We have measured the vector and tensor polarization of an atomic deuterium target as a function of the target density. The polarized deuterium was produced in an atomic beam source and injected into a storage cell. For this experiment, the atomic beam source was operated without rf transitions, in order to avoid complications from the unknown efficiency of these transitions. In this mode, the atomic beam is vector and tensor polarized and both polarizations can be measured simultaneously. We used a 1.2-cm-diam and 27-cm-long storage cell, which yielded an average target density between 3 and 9x10 11 at/cm 3 . We find that the tensor polarization decreases with increasing target density while the vector polarization remains constant. The data are in quantitative agreement with the calculated effect of spin exchange between deuterium atoms at low field

  2. Development of polarized negative hydrogen ion source with resonant charge-exchange plasma ionizer

    Science.gov (United States)

    Belov, A. S.; Esin, S. K.; Netchaeva, L. P.; Turbabin, A. V.; Vasil'Ev, G. A.

    2001-06-01

    Polarized negative hydrogen ion beam with peak current of 2.5 mA has been obtained from an atomic beam-type polarized ion source of Institute for Nuclear Research, Moscow. The intensity improvement has been achieved due to increase of efficiency of conversion of polarized hydrogen atoms into polarized negative ions. New converter for production of deuterium plasma with high density of unpolarized negative ions is described. Limitations of the method and possible improvements are discussed. .

  3. Building AN International Polar Data Coordination Network

    Science.gov (United States)

    Pulsifer, P. L.; Yarmey, L.; Manley, W. F.; Gaylord, A. G.; Tweedie, C. E.

    2013-12-01

    In the spirit of the World Data Center system developed to manage data resulting from the International Geophysical Year of 1957-58, the International Polar Year 2007-2009 (IPY) resulted in significant progress towards establishing an international polar data management network. However, a sustained international network is still evolving. In this paper we argue that the fundamental building blocks for such a network exist and that the time is right to move forward. We focus on the Arctic component of such a network with linkages to Antarctic network building activities. A review of an important set of Network building blocks is presented: i) the legacy of the IPY data and information service; ii) global data management services with a polar component (e.g. World Data System); iii) regional systems (e.g. Arctic Observing Viewer; iv) nationally focused programs (e.g. Arctic Observing Viewer, Advanced Cooperative Arctic Data and Information Service, Polar Data Catalogue, Inuit Knowledge Centre); v) programs focused on the local (e.g. Exchange for Local Observations and Knowledge of the Arctic, Geomatics and Cartographic Research Centre). We discuss current activities and results with respect to three priority areas needed to establish a strong and effective Network. First, a summary of network building activities reports on a series of productive meetings, including the Arctic Observing Summit and the Polar Data Forum, that have resulted in a core set of Network nodes and participants and a refined vision for the Network. Second, we recognize that interoperability for information sharing fundamentally relies on the creation and adoption of community-based data description standards and data delivery mechanisms. There is a broad range of interoperability frameworks and specifications available; however, these need to be adapted for polar community needs. Progress towards Network interoperability is reviewed, and a prototype distributed data systems is demonstrated. We

  4. Polar Domain Discovery with Sparkler

    Science.gov (United States)

    Duerr, R.; Khalsa, S. J. S.; Mattmann, C. A.; Ottilingam, N. K.; Singh, K.; Lopez, L. A.

    2017-12-01

    The scientific web is vast and ever growing. It encompasses millions of textual, scientific and multimedia documents describing research in a multitude of scientific streams. Most of these documents are hidden behind forms which require user action to retrieve and thus can't be directly accessed by content crawlers. These documents are hosted on web servers across the world, most often on outdated hardware and network infrastructure. Hence it is difficult and time-consuming to aggregate documents from the scientific web, especially those relevant to a specific domain. Thus generating meaningful domain-specific insights is currently difficult. We present an automated discovery system (Figure 1) using Sparkler, an open-source, extensible, horizontally scalable crawler which facilitates high throughput and focused crawling of documents pertinent to a particular domain such as information about polar regions. With this set of highly domain relevant documents, we show that it is possible to answer analytical questions about that domain. Our domain discovery algorithm leverages prior domain knowledge to reach out to commercial/scientific search engines to generate seed URLs. Subject matter experts then annotate these seed URLs manually on a scale from highly relevant to irrelevant. We leverage this annotated dataset to train a machine learning model which predicts the `domain relevance' of a given document. We extend Sparkler with this model to focus crawling on documents relevant to that domain. Sparkler avoids disruption of service by 1) partitioning URLs by hostname such that every node gets a different host to crawl and by 2) inserting delays between subsequent requests. With an NSF-funded supercomputer Wrangler, we scaled our domain discovery pipeline to crawl about 200k polar specific documents from the scientific web, within a day.

  5. Linear polarization of BY Draconis

    International Nuclear Information System (INIS)

    Koch, R.H.; Pfeiffer, R.J.

    1976-01-01

    Linear polarization measurements are reported in four bandpasses for the flare star BY Dra. The red polarization is intrinsically variable at a confidence level greater than 99 percent. On a time scale of many months, the variability is not phase-locked to either a rotational or a Keplerian ephemeris. The observations of the three other bandpasses are useful principally to indicate a polarization spectrum rising toward shorter wavelengths

  6. Polarity in Mammalian Epithelial Morphogenesis

    OpenAIRE

    Roignot, Julie; Peng, Xiao; Mostov, Keith

    2013-01-01

    Cell polarity is fundamental for the architecture and function of epithelial tissues. Epithelial polarization requires the intervention of several fundamental cell processes, whose integration in space and time is only starting to be elucidated. To understand what governs the building of epithelial tissues during development, it is essential to consider the polarization process in the context of the whole tissue. To this end, the development of three-dimensional organotypic cell culture model...

  7. A polarized alkali ion source

    International Nuclear Information System (INIS)

    Boettger, R.; Tungate, G.; Bauer, B.; Egelhof, P.; Moebius, K.H.; Steffens, E.

    1978-01-01

    The beam foil technique has been applied to detect nuclear vector polarization of a 10 keV 23 Na + beam. The result was about 70% of the atomic beam polarization thus limiting the depolarization by the surface ionizer to at most 30%. In a Coulomb excitation experiment with a tensor polarized 42 MeV 23 Na 7+ beam an effect of 0.011 +- 0.003 was measured yielding a value of t 20 approx. 0.04 for the beam polarization. The depolarization during the acceleration process can be estimated to be about 0.8. (orig.) [de

  8. The SLAC polarized electron source

    International Nuclear Information System (INIS)

    Tang, H.; Alley, R.; Frisch, J.

    1995-06-01

    The SLAC polarized electron source employs a photocathode DC high voltage gun with a loadlock and a YAG pumped Ti:sapphire laser system for colliding beam experiments or a flash lamp pumped Ti:sapphire laser for fixed target experiments. It uses a thin, strained GaAs(100) photocathode, and is capable of producing a pulsed beam with a polarization of ≥80% and a peak current exceeding 10 A. Its operating efficiency has reached 99%. The physics and technology of producing high polarization electron beams from a GaAs photocathode will be reviewed. The prospects of realizing a polarized electron source for future linear colliders will also be discussed

  9. Calibration of Airborne Multiangle SpectroPolarimetric Imager (AirMSPI) polarization measurements, and in-flight comparisons with the Research Scanning Polarimeter (RSP) and the Spectropolarimeter for Planetary EXploration (SPEX)

    Science.gov (United States)

    van Harten, G.; Diner, D. J.; Rheingans, B. E.; Daugherty, B. J.; Xu, F.; Bull, M. A.; Tkatcheva, I. N.; Garay, M. J.; Seidel, F.; Chipman, R. A.; Smit, M.

    2016-12-01

    The Airborne Multiangle SpectroPolarimetric Imager (AirMSPI) is a remote sensing instrument for the characterization of atmospheric aerosols and clouds. AirMSPI, flying onboard the NASA ER-2 aircraft at 20 km altitude, participates in field campaigns since 2013, including ORACLES (2016). The pushbroom camera is mounted on a programmable, motorized gimbal for multi-angle observations at 10x10 m2 resolution. Eight spectral bands within 355-935 nm are recorded, 3 of which also measure linear polarization. Photoelastic modulators (PEMs) encode the polarized and total intensities in each polarimetric pixel as the amplitude and offset of a modulated intensity pattern, such that the ratio of the two is insensitive to pixel-to-pixel differences. This technique, developed to enable the high-accuracy imaging polarimetry required for aerosol species discrimination, will also be applied in the Multi-Angle Imager for Aerosols (MAIA) satellite instrument. We present the calibration and accuracy validation of AirMSPI polarization measurements. The main calibration, describing the instrument's response to any degree (DoLP) and angle of linear polarization, is performed in the lab using a recently updated, carefully designed and characterized polarization state generator (PSG-2). Validation measurements using an independent polarimeter show agreement in DoLP to within 0.001 for several DoLPs across the 0-1 range. The PEMs' retardances and phases, which are different and not necessarily stable in flight, are extracted from measurements of the on-board validator, a partially polarized light source located inside the instrument housing, which is viewed before and after each target. Although this calibration does not rely on the validator's DoLP, and the validator was not designed for DoLP calibration, the frequent measurements of its DoLP provide an upper limit for AirMSPI's in-flight polarimetric stability, which is 0.001. A correction for the actual PEM retardances and phases in the

  10. Spin-Polarization in Quasi-Magnetic Tunnel Junctions

    Science.gov (United States)

    Xie, Zheng-Wei; Li, Ling

    2017-05-01

    Spin polarization in ferromagnetic metal/insulator/spin-filter barrier/nonmagnetic metal, referred to as quasi-magnetic tunnel junctions, is studied within the free-electron model. Our results show that large positive or negative spin-polarization can be obtained at high bias in quasi-magnetic tunnel junctions, and within large bias variation regions, the degree of spin-polarization can be linearly tuned by bias. These linear variation regions of spin-polarization with bias are influenced by the barrier thicknesses, barrier heights and molecular fields in the spin-filter (SF) layer. Among them, the variations of thickness and heights of the insulating and SF barrier layers have influence on the value of spin-polarization and the linear variation regions of spin-polarization with bias. However, the variations of molecular field in the SF layer only have influence on the values of the spin-polarization and the influences on the linear variation regions of spin-polarization with bias are slight. Supported by the Key Natural Science Fund of Sichuan Province Education Department under Grant Nos 13ZA0149 and 16ZA0047, and the Construction Plan for Scientific Research Innovation Team of Universities in Sichuan Province under Grant No 12TD008.

  11. Code of Conduct on the Safety of Research Reactors

    International Nuclear Information System (INIS)

    2006-09-01

    The Board of Governors of the International Atomic Energy Agency (IAEA) adopted the Code of Conduct on the Safety of Research Reactors on 8 March 2004. The Board's action was the culmination of several years of work to develop the Code and obtain a consensus on its provisions. The process leading to the Code began in 1998, when the International Nuclear Safety Advisory Group (INSAG) informed the Director General of concerns about the safety of research reactors. In 2000, INSAG recommended that the Secretariat begin developing an international protocol or a similar legal instrument to address those concerns. In September 2000, in resolution GC(44)/RES/14, the General Conference requested the Secretariat ''within its available resources, to continue work on exploring options to strengthen the international nuclear safety arrangements for civil research reactors, taking due account of input from INSAG and the views of other relevant bodies''. A working group convened by the Secretariat pursuant to that request recommended that ''the Agency consider establishing an international action plan for research reactors'' and that the action plan include preparation of a Code of Conduct ''that would clearly establish the desirable attributes for management of research reactor safety''. In September 2001, the Board requested that the Secretariat develop and implement, in conjunction with Member States, an international research reactor safety enhancement plan which included preparation of a Code of Conduct on the Safety of Research Reactors. Subsequently, in resolution GC(45)/RES/10.A, the General Conference endorsed the Board's request. Pursuant to that request, a Code of Conduct on the Safety of Research Reactors was drafted at two meetings of an Open-ended Working Group of Legal and Technical Experts. This draft Code of Conduct was circulated to all Member States for comment. On the basis of the responses received, a revised draft of the Code was prepared by the Secretariat

  12. Create a Polarized Light Show.

    Science.gov (United States)

    Conrad, William H.

    1992-01-01

    Presents a lesson that introduces students to polarized light using a problem-solving approach. After illustrating the concept using a slinky and poster board with a vertical slot, students solve the problem of creating a polarized light show using Polya's problem-solving methods. (MDH)

  13. Carbon nanotube fiber terahertz polarizer

    Energy Technology Data Exchange (ETDEWEB)

    Zubair, Ahmed [Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005 (United States); Tsentalovich, Dmitri E.; Young, Colin C. [Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005 (United States); Heimbeck, Martin S. [Charles M. Bowden Laboratory, Aviation & Missile Research, Development, and Engineering Center (AMRDEC), Redstone Arsenal, Alabama 35898 (United States); Everitt, Henry O. [Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005 (United States); Charles M. Bowden Laboratory, Aviation & Missile Research, Development, and Engineering Center (AMRDEC), Redstone Arsenal, Alabama 35898 (United States); Pasquali, Matteo [Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005 (United States); Department of Chemistry, Rice University, Houston, Texas 77005 (United States); Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005 (United States); Kono, Junichiro, E-mail: kono@rice.edu [Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005 (United States); Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005 (United States); Department of Physics and Astronomy, Rice University, Houston, Texas 77005 (United States)

    2016-04-04

    Conventional, commercially available terahertz (THz) polarizers are made of uniformly and precisely spaced metallic wires. They are fragile and expensive, with performance characteristics highly reliant on wire diameters and spacings. Here, we report a simple and highly error-tolerant method for fabricating a freestanding THz polarizer with nearly ideal performance, reliant on the intrinsically one-dimensional character of conduction electrons in well-aligned carbon nanotubes (CNTs). The polarizer was constructed on a mechanical frame over which we manually wound acid-doped CNT fibers with ultrahigh electrical conductivity. We demonstrated that the polarizer has an extinction ratio of ∼−30 dB with a low insertion loss (<0.5 dB) throughout a frequency range of 0.2–1.1 THz. In addition, we used a THz ellipsometer to measure the Müller matrix of the CNT-fiber polarizer and found comparable attenuation to a commercial metallic wire-grid polarizer. Furthermore, based on the classical theory of light transmission through an array of metallic wires, we demonstrated the most striking difference between the CNT-fiber and metallic wire-grid polarizers: the latter fails to work in the zero-spacing limit, where it acts as a simple mirror, while the former continues to work as an excellent polarizer even in that limit due to the one-dimensional conductivity of individual CNTs.

  14. Polarization-preserving holey fibers

    DEFF Research Database (Denmark)

    Broeng, Jes; Mogilevtsev, Dmitri; Libori, Stig E. Barkou

    2001-01-01

    In this work we suggest and discuss a microstructure of air capillaries with elliptical cross-section in a tread of glass that gives opportunity for Creation of polarization-preserving fiber with very small beat length between the fundamental modes of different polarization...

  15. Polarized Scintillating Targets at Psi

    Science.gov (United States)

    van den Brandt, B.; Bunyatova, E. I.; Hautle, P.; Konter, J. A.; Mango, S.

    2001-02-01

    Scintillating polarized targets are now routinely available: blocks of 18×18×5 mm scintillating organic polymer, doped with TEMPO, polarized dynamically in a field of 2.5 T in a vertical 3He-4He dilution refrigerator. A 19 mm diameter plastic lightguide transports the scintillation light from the sample in the mixing chamber to a photomultiplier outside the cryostat.

  16. UV Coatings, Polarization, and Coronagraphy

    Science.gov (United States)

    Bolcar, Matthew R.; Quijada, Manuel; West, Garrett; Balasubramanian, Bala; Krist, John; Martin, Stefan; Sabatke, Derek

    2016-01-01

    Presenation for the Large UltraViolet Optical Infrared (LUVOIR) and Habitable Exoplanet Imager (HabEx) Science and Technology Definition Teams (STDT) on technical considerations regarding ultraviolet coatings, polarization, and coronagraphy. The presentations review the state-of-the-art in ultraviolet coatings, how those coatings generate polarization aberrations, and recent study results from both the LUVOIR and HabEx teams.

  17. Polarization Imaging and Insect Vision

    Science.gov (United States)

    Green, Adam S.; Ohmann, Paul R.; Leininger, Nick E.; Kavanaugh, James A.

    2010-01-01

    For several years we have included discussions about insect vision in the optics units of our introductory physics courses. This topic is a natural extension of demonstrations involving Brewster's reflection and Rayleigh scattering of polarized light because many insects heavily rely on optical polarization for navigation and communication.…

  18. Climate Drives Polar Bear Origins

    Science.gov (United States)

    In their provocative analysis of northern bears (“Nuclear genomic sequences reveal that polar bears are an old and distinct bear lineage,” Reports, 20 April, p. 344), F. Hailer et al. use independent nuclear loci to show that polar bears originated during the middle Pleistocene, rather than during t...

  19. Teach the Teacher! Building ROV's to Teach Polar Science

    Science.gov (United States)

    Bartholow, S.; Warburton, J.

    2014-12-01

    In 2013, the Arctic Research Consortium of the United States (ARCUS) a non-profit corporation consisting of institutions organized and operated for educational, professional, or scientific purposes, received funding from Lockheed Martin to design and host a workshop for teachers. Middle School teachers participated in a three-day Polar Workshop designed to enlighten teachers regarding marine polar science and exploration through the use of remotely operated vehicles, or ROVs. The Polar Workshop was offered as part of a teacher professional development activity that took at the Monterey Bay Aquarium Research Institute. The workshop provided training for teachers alongside polar scientists and teacher mentors. The overall purpose of the workshop was to teach teachers about marine polar science and technology that could be used with students in classrooms. Teachers were teamed with a polar scientist and with a teacher mentor for the three-day project. Results from the evaluation of the Polar Workshop indicate this workshop was an excellent opportunity for the teachers who participated as well as for the scientists. In this presentation, we will share the evaluation data, best practices of the workshop model, and how teacher mentors, scientists, and graduate students can help teach teachers successfully.

  20. Integrins and epithelial cell polarity.

    Science.gov (United States)

    Lee, Jessica L; Streuli, Charles H

    2014-08-01

    Cell polarity is characterised by differences in structure, composition and function between at least two poles of a cell. In epithelial cells, these spatial differences allow for the formation of defined apical and basal membranes. It has been increasingly recognised that cell-matrix interactions and integrins play an essential role in creating epithelial cell polarity, although key gaps in our knowledge remain. This Commentary will discuss the mounting evidence for the role of integrins in polarising epithelial cells. We build a model in which both inside-out signals to polarise basement membrane assembly at the basal surface, and outside-in signals to control microtubule apical-basal orientation and vesicular trafficking are required for establishing and maintaining the orientation of epithelial cell polarity. Finally, we discuss the relevance of the basal integrin polarity axis to cancer. This article is part of a Minifocus on Establishing polarity. © 2014. Published by The Company of Biologists Ltd.

  1. Hyperon polarization: An experimental overview

    International Nuclear Information System (INIS)

    Lach, J.

    1992-12-01

    The fact that inclusively produced hyperons are produced with significant polarization was first discovered at Fermilab about seventeen years ago. This and subsequent experiments showed that Λ degree were produced polarized while bar Λ degree had no polarization in the same kinematical region. This set the stage for many experiments which showed that most hyperons are produced polarized. Recent Fermilab experiments have showed that this phenomena is even more complex than previously thought and theoretical understanding is still lacking. Nevertheless polarized hyperon beams have been an extremely useful experimental tool in measuring hyperon magnetic moments and hyperon β-decay. Recently, hyperon radiative decays have been studied and magnetic moment precession of channeled particles in bent crystals has been observed

  2. A review of polarized ion sources

    International Nuclear Information System (INIS)

    Schmor, P.W.

    1995-06-01

    The two main types of polarized ion sources in use on accelerators today are the Atomic Beam Polarized Ion Source (ABIS) source and the Optically Pumped Polarized Ion Source (OPPIS). Both types can provide beams of nuclearly polarized light ions which are either positively or negatively charged. Heavy ion polarized ion sources for accelerators are being developed. (author). 35 refs., 1 tab

  3. Operation of the optically pumped polarized H- source at LAMPF

    International Nuclear Information System (INIS)

    York, R.L.; Tupa, D.; Swenson, D.R.; van Dyck, O.B.

    1991-01-01

    We report on the first five months of operation of the Optically Pumped Polarized Ion Source (OPPIS) for the nuclear physics research program at LAMPF. The LAMPF OPPIS is unique in using Ti: Sapphire lasers to polarize the potassium charge-exchange medium, and until recently was unique in using a superconducting magnet in the ECR source and polarizer regions. The ECR extraction electrode biasing arrangement is also unique. Typical performance was 25 microamps of peak current (measured at 750 keV) with 55% beam polarization or 15 microamps at 62%. Ion source availability was greater than 90%. We also report our planned improvements in preparation for research operation in May of 1991. 3 refs., 4 figs

  4. Recent progress on HYSPEC, and its polarization analysis capabilities

    Directory of Open Access Journals (Sweden)

    Winn Barry

    2015-01-01

    Full Text Available HYSPEC is a high-intensity, direct-geometry time-of-flight spectrometer at the Spallation Neutron Source, optimized for measurement of excitations in small single-crystal specimens with optional polarization analysis capabilities. The incident neutron beam is monochromated using a Fermi chopper with short, straight blades, and is then vertically focused by Bragg scattering onto the sample position by either a highly oriented pyrolitic graphite (unpolarized or a Heusler (polarized crystal array. Neutrons are detected by a bank of 3He tubes that can be positioned over a wide range of scattering angles about the sample axis. HYSPEC entered the user program in February 2013 for unpolarized experiments, and is already experiencing a vibrant research program. Polarization analysis will be accomplished by using the Heusler crystal array to polarize the incident beam, and either a 3He spin filter or a supermirror wide-angle polarization analyser to analyse the scattered beam. The 3He spin filter employs the spin-exchange optical pumping technique. A 60∘ wide angle 3He cell that matches the detector coverage will be used for polarization analysis. The polarized gas in the post-sample wide angle cell is designed to be periodically and automatically refreshed with an adjustable pressure of polarized gas, optically pumped in a separate cell and then transferred to the wide angle cell. The supermirror analyser has 960 supermirror polarizers distributed over 60∘, and has been characterized at the Swiss Spallation Neutron Source. The current status of the instrument and the development of its polarization analysis capabilities are presented.

  5. Atmospheric Polarization Imaging with Variable Aerosols, Clouds, and Surface Albedo

    Science.gov (United States)

    2013-07-01

    Continuous outdoor operation of an all-sky polarization imager,” Proc. SPIE 7672 (Polarization: Measurement, Analysis , and Remote Sensing IX), 76720A-1-7, 7...condensation nuclei activity and hygroscopicity of in-situ biomass burning aerosol,” American Assoc. Aerosol Research 31 st Annual Conference...tunable liquid crystal variable retarders (LCVRs) allows the API to achieve much faster Stokes-image acquisition than instruments that rely on

  6. POLARIZED LIGHT IN PHYSIOTHERAPY

    Directory of Open Access Journals (Sweden)

    L. D. Tondiy

    2015-12-01

    Full Text Available The data on polarized light (PS - a new promising treatment, rehabilitation and prevention, which took its deserved place among the known therapeutic physical factors and may even compete with laser radiation of low and LED therapy. It is reflected the significant contribution of domestic scientists in the study of aircraft action on the body, its introduction in the treatment, rehabilitation and prevention of grippe, ARI. These action's mechanisms of the aircraft on the electro-physiological processes in the body that have the leading role in the regulation of its life. The new moment in the study of aircraft on the body is the evidence of its positive impact on the mechanisms of self body - its different units: the disease's banning - a revitalization of the stress-protective, stress-limiting system antioxidial, detoxification and other protection systems, the formation by the body antiviral and antimicrobial specific substances (interferon and lysozyme, activation of the immune system, phagocytosis, protective functions of skin. The protective and mobilizing role of the second link is studied: which is triggered in case of occurrence of disease or preexisting diseases: PL mobilized processes of restitution, reparations, compensation, immunity and microcirculation. The authors studied the possibility of aircraft's using to enhance performance, reduce side effects of physical factors, which are often used in the treatment (electric methods, treatment by sound, fresh and mineral water, etc..

  7. Update of the Polar SWIFT model for polar stratospheric ozone loss (Polar SWIFT version 2)

    Science.gov (United States)

    Wohltmann, Ingo; Lehmann, Ralph; Rex, Markus

    2017-07-01

    The Polar SWIFT model is a fast scheme for calculating the chemistry of stratospheric ozone depletion in polar winter. It is intended for use in global climate models (GCMs) and Earth system models (ESMs) to enable the simulation of mutual interactions between the ozone layer and climate. To date, climate models often use prescribed ozone fields, since a full stratospheric chemistry scheme is computationally very expensive. Polar SWIFT is based on a set of coupled differential equations, which simulate the polar vortex-averaged mixing ratios of the key species involved in polar ozone depletion on a given vertical level. These species are O3, chemically active chlorine (ClOx), HCl, ClONO2 and HNO3. The only external input parameters that drive the model are the fraction of the polar vortex in sunlight and the fraction of the polar vortex below the temperatures necessary for the formation of polar stratospheric clouds. Here, we present an update of the Polar SWIFT model introducing several improvements over the original model formulation. In particular, the model is now trained on vortex-averaged reaction rates of the ATLAS Chemistry and Transport Model, which enables a detailed look at individual processes and an independent validation of the different parameterizations contained in the differential equations. The training of the original Polar SWIFT model was based on fitting complete model runs to satellite observations and did not allow for this. A revised formulation of the system of differential equations is developed, which closely fits vortex-averaged reaction rates from ATLAS that represent the main chemical processes influencing ozone. In addition, a parameterization for the HNO3 change by denitrification is included. The rates of change of the concentrations of the chemical species of the Polar SWIFT model are purely chemical rates of change in the new version, whereas in the original Polar SWIFT model, they included a transport effect caused by the

  8. EDITORIAL: Non-polar and semipolar nitride semiconductors Non-polar and semipolar nitride semiconductors

    Science.gov (United States)

    Han, Jung; Kneissl, Michael

    2012-02-01

    Throughout the history of group-III-nitride materials and devices, scientific breakthroughs and technological advances have gone hand-in-hand. In the late 1980s and early 1990s, the discovery of the nucleation of smooth (0001) GaN films on c-plane sapphire and the activation of p-dopants in GaN led very quickly to the realization of high-brightness blue and green LEDs, followed by the first demonstration of GaN-based violet laser diodes in the mid 1990s. Today, blue InGaN LEDs boast record external quantum efficiencies exceeding 80% and the emission wavelength of the InGaN-based laser diode has been pushed into the green spectral range. Although these tremenduous advances have already spurred multi-billion dollar industries, there are still a number of scientific questions and technological issues that are unanswered. One key challenge is related to the polar nature of the III-nitride wurtzite crystal. Until a decade ago all research activities had almost exclusively concentrated on (0001)-oriented polar GaN layers and heterostructures. Although the device characteristics seem excellent, the strong polarization fields at GaN heterointerfaces can lead to a significant deterioration of the device performance. Triggered by the first demonstration non-polar GaN quantum wells grown on LiAlO2 by Waltereit and colleagues in 2000, impressive advances in the area of non-polar and semipolar nitride semiconductors and devices have been achieved. Today, a large variety of heterostructures free of polarization fields and exhibiting exceptional electronic and optical properties have been demonstrated, and the fundamental understanding of polar, semipolar and non-polar nitrides has made significant leaps forward. The contributions in this Semiconductor Science and Technology special issue on non-polar and semipolar nitride semiconductors provide an impressive and up-to-date cross-section of all areas of research and device physics in this field. The articles cover a wide range of

  9. Nuclear physics with polarized particles

    CERN Document Server

    Paetz gen Schieck, Hans

    2012-01-01

    The measurement of spin-polarization observables in reactions of nuclei and particles is of great utility and advantage when the effects of single-spin sub-states are to be investigated. Indeed, the unpolarized differential cross-section encompasses the averaging over the spin states of the particles, and thus loses details of the interaction process. This introductory text combines, in a single volume, course-based lecture notes on spin physics and on polarized-ion sources with the aim of providing a concise yet self-contained starting point for newcomers to the field, as well as for lecturers in search of suitable material for their courses and seminars. A significant part of the book is devoted to introducing the formal theory-a description of polarization and of nuclear reactions with polarized particles. The remainder of the text describes the physical basis of methods and devices necessary to perform experiments with polarized particles and to measure polarization and polarization effects in nuclear rea...

  10. Few-body experiments with polarized beams and polarized targets

    International Nuclear Information System (INIS)

    Simmons, J.E.

    1983-01-01

    A survey is presented concerning recent polarization experiments in the elastic p-d, p- 3 He, and p- 4 He systems. Mention is made of selected neutron experiments. The nominal energy range is 10 to 1000 MeV. Recent results and interpretations of the p-d system near 10 MeV are discussed. New experiments on the energy dependence of back angle p-d tensor polarization are discussed with respect to resolution of discrepancies and difficulty of theoretical interpretation. Progress is noted concerning multiple scattering interpretation of forward p-d deuteron polarization. Some new results are presented concerning the p- 3 He system and higher energy p- 4 He polarization experiments. 52 references

  11. A Proposal to the Department of Energy for The Fabrication of a Very High Energy Polarized Gama Ray Beam Facility and A Program of Medium Energy Physics Research at The National Synchrotron Light Source

    Energy Technology Data Exchange (ETDEWEB)

    Sandorfi, A.M.; LeVine, M.J.; Thorn, C.E.; Giordano, G.; Matone, G.

    1982-09-01

    This proposal requests support for the fabrication and operation of a modest facility that would provide relatively intense beams of monochromatic and polarized photons with energies in the range of several hundreds of MeV. These {gamma} rays would be produced by Compton backscattering laser light from the electrons circulating in the 2.5-3.0 GeV 'X-RAY' storage ring of the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory. The excellent emittance, phase space, and high current of this state-of-the-art storage ring will allow the production of 2 x 10{sup 7} {gamma} rays per second. These photons would be tagged by detecting the scattered electrons, thereby determining the energy to 2.7 MeV for all {gamma}-ray energies. The efficiency of this tagging procedure is 100% and the {gamma}-ray beam would be essentially background free. Tagging will also allow the flexibility of operating with a dynamic range as large as 200 MeV in photon energy while still preserving high resolution and polarization. These beams will permit a fruitful study of important questions in medium-energy nuclear physics. The initial goals of this program are to reach reliable operation with photon energies up to 300 MeV and to develop {gamma}-ray beams with energies up to about 500 MeV. To demonstrate reliable operation, a modest physics program is planned that, for the most part, utilizes existing magnets and detector systems but nonetheless addresses several important outstanding problems. Gamma ray beams of the versatility, intensity, energy, and resolution that can be achieved at this facility are not currently available at any other world facility either existing or under construction. Furthermore, the proposed program would produce the first intense source of medium-energy {gamma} rays that are polarized. Because of the difficulties in producing such polarized beams, it is very unlikely that viable alternate sources can be developed in the near future; at

  12. Acceleration of polarized proton beams

    International Nuclear Information System (INIS)

    Roser, T.

    1998-01-01

    The acceleration of polarized beams in circular accelerators is complicated by the numerous depolarizing spin resonances. Using a partial Siberian snake and a rf dipole that ensure stable adiabatic spin motion during acceleration has made it possible to accelerate polarized protons to 25 GeV at the Brookhaven AGS. Full Siberian snakes are being developed for RHIC to make the acceleration of polarized protons to 250 GeV possible. A similar scheme is being studied for the 800 GeV HERA proton accelerator

  13. Polarimetry with azimuthally polarized light

    Science.gov (United States)

    de Sande, Juan Carlos González; Piquero, Gemma; Santarsiero, Massimo

    2018-03-01

    Nonuniformly polarized light can be used for Mueller polarimetry of homogeneous linear samples. In this work, a set up based on using azimuthally polarized input light and a modified commercial light polarimeter is proposed and developed. With this set up, a Mueller submatrix of a sample can be obtained by measuring the Stokes parameters at only three different positions across the output beam section. Symmetry constraints for linear deterministic samples allow the complete Mueller matrix to be deduced for this kind of specimens. The experimental results obtained for phase plates and for a linear polarizer confirm the validity of the proposed method.

  14. Polarized deuteron elastic scattering from a polarized proton target

    International Nuclear Information System (INIS)

    Schmelzer, R.; Kuiper, H.; Schoeberl, M.; Berber, S.; Hilmert, H.; Koeppel, R.; Pferdmenges, R.; Zankel, H.

    1983-01-01

    Measurements are reported of the spin correlation parameter Cy,y for the elastic scattering of 10.0 MeV vector polarized deuterons from a polarized proton target at five CM angles (76 0 ,85 0 ,98 0 ,115 0 ,132 0 ). The experimental results are compared with different predictions. A Faddeev type calculation on the basis of local potentials also including approximate Coulomb distortion is favoured by our experimental results. (orig.)

  15. PolarHub: A Global Hub for Polar Data Discovery

    Science.gov (United States)

    Li, W.

    2014-12-01

    This paper reports the outcome of a NSF project in developing a large-scale web crawler PolarHub to discover automatically the distributed polar dataset in the format of OGC web services (OWS) in the cyberspace. PolarHub is a machine robot; its goal is to visit as many webpages as possible to find those containing information about polar OWS, extract this information and store it into the backend data repository. This is a very challenging task given huge data volume of webpages on the Web. Three unique features was introduced in PolarHub to make it distinctive from earlier crawler solutions: (1) a multi-task, multi-user, multi-thread support to the crawling tasks; (2) an extensive use of thread pool and Data Access Object (DAO) design patterns to separate persistent data storage and business logic to achieve high extendibility of the crawler tool; (3) a pattern-matching based customizable crawling algorithm to support discovery of multi-type geospatial web services; and (4) a universal and portable client-server communication mechanism combining a server-push and client pull strategies for enhanced asynchronous processing. A series of experiments were conducted to identify the impact of crawling parameters to the overall system performance. The geographical distribution pattern of all PolarHub identified services is also demonstrated. We expect this work to make a major contribution to the field of geospatial information retrieval and geospatial interoperability, to bridge the gap between data provider and data consumer, and to accelerate polar science by enhancing the accessibility and reusability of adequate polar data.

  16. An Integrated Imaging Detector of Polarization and Spectral Content

    Science.gov (United States)

    Rust, D. M.; Thompson, K. E.

    1993-01-01

    A new type of image detector has been designed to simultaneously analyze the polarization of light at all picture elements in a scene. The Integrated Dual Imaging Detector (IDID) consists of a polarizing beamsplitter bonded to a charge-coupled device (CCD), with signal-analysis circuitry and analog-to-digital converters, all integrated on a silicon chip. It should be capable of 1:10(exp 4) polarization discrimination. The IDID should simplify the design and operation of imaging polarimeters and spectroscopic imagers used, for example, in atmospheric and solar research. Innovations in the IDID include (1) two interleaved 512 x 1024-pixel imaging arrays (one for each polarization plane); (2) large dynamic range (well depth of 10(exp 6) electrons per pixel); (3) simultaneous readout of both images at 10 million pixels per second each; (4) on-chip analog signal processing to produce polarization maps in real time; (5) on-chip 10-bit A/D conversion. When used with a lithium-niobate Fabry-Perot etalon or other color filter that can encode spectral information as polarization, the IDID can collect and analyze simultaneous images at two wavelengths. Precise photometric analysis of molecular or atomic concentrations in the atmosphere is one suggested application. When used in a solar telescope, the IDID will charge the polarization, which can then be converted to maps of the vector magnetic fields on the solar surface.

  17. Variety of Polarized Line Profiles in Interacting Supernovae

    Science.gov (United States)

    Hoffman, Jennifer L.; Huk, L. N.; Peters, C. L.

    2013-01-01

    The dense circumstellar material that creates strong emission lines in the spectra of interacting supernovae also gives rise to complex line polarization behavior. Viewed in polarized light, the emission line profiles of these supernovae encode information about the geometrical and optical characteristics of their surrounding circumstellar material (CSM) that is inaccessible by other observational techniques. To facilitate quantitative interpretation of these spectropolarimetric signatures, we have created a large grid of model polarized line profiles using a three-dimensional radiative transfer code that simulates polarization via electron and resonant/fluorescent line scattering. The simulated polarized lines take on an array of profile shapes that vary with viewing angle and CSM properties. We present the major results from the grid and investigate the dependence of polarized line profiles on CSM characteristics including temperature, optical depth, and geometry. These results will allow more straightforward interpretation of polarized line profiles in interacting supernovae than has previously been possible. This research is supported by the National Science Foundation through the AAG program and the XSEDE collaboration, and uses the resources of the Texas Advanced Computing Center.

  18. POLAR ORGANIC CHEMICAL INTEGRATIVE SAMPLING ...

    Science.gov (United States)

    The purpose of the research presented in this paper is two-fold: (1) to demonstrate the 4 coupling of two state-of-the-art techniques: a time-weighted polar organic integrative sampler (POCIS) and micro-liquid chromatography-electrospray/ion trap mass spectrometry (u-LC-6 ES/ITMS); and (2) the assessment of these methodologies in a real-world environment -wastewater effluent - for detecting six drugs (four prescription and two illicit). In the effluent from three wastewater treatment plants (WWTP), azithromycin was detected at concentrations ranging from 15ng/L to 66ng/L, equivalent to the total annual release of 0.4 -4 kg into the receiving waters. Detected and confirmed in the effluent from two WWTPs were two illicit drugs methamphetamine and methylenedioxymethamphetamine (MDMA), at 2ng/L and 0.5ng/L, respectively. While the ecotoxicological significance of drugs in environmental matrices, particularly water, has not been closely examined, it can only be surmised that these substances have the potential to adversely affect biota that are continuously exposed to them even at very low levels. The potential for chronic affects on human health is also unknown, but of increasing concern due to the multi use character of water, particularly in densely populated arid areas. The research focused on in the subtasks is the development and application of state-of the-art technologies to meet the needs of the public, Office of Water, and ORD in the area of Water Quality

  19. Polar source analysis : technical memorandum

    Science.gov (United States)

    2017-09-29

    The following technical memorandum describes the development, testing and analysis of various polar source data sets. The memorandum also includes recommendation for potential inclusion in future releases of AEDT. This memorandum is the final deliver...

  20. Anodic Concentration Polarization in SOFCs

    Energy Technology Data Exchange (ETDEWEB)

    Williford, Rick E.; Chick, Lawrence A.; Maupin, Gary D.; Simner, Steve P.; Stevenson, Jeffry W.; Khaleel, Mohammad A.; Wachsman, ED, et al

    2003-08-01

    Concentration polarization is important because it determines the maximum power output of a solid oxide fuel cell (SOFC) at high fuel utilization. Anodic concentration polarization occurs when the demand for reactants exceeds the capacity of the porous ceramic anode to supply them by gas diffusion mechanisms. High tortuosities (bulk diffusion resistances) are often assumed to explain this behavior. However, recent experiments show that anodic concentration polarization originates in the immediate vicinity of the reactive triple phase boundary (TPB) sites near the anode/electrolyte interface. A model is proposed to describe how concentration polarization is controlled by two localized phenomena: competitive adsorption of reactants in areas adjacent to the reactive TPB sites, followed by relatively slow surface diffusion to the reactive sites. Results suggest that future SOFC design improvements should focus on optimization of the reactive area, adsorption, and surface diffusion at the anode/electrolyte interface.

  1. The definition of cross polarization

    DEFF Research Database (Denmark)

    Ludwig, Arthur

    1973-01-01

    There are at least three different definitions of cross polarization used in the literature. The alternative definitions are discussed with respect to several applications, and the definition which corresponds to one standard measurement practice is proposed as the best choice....

  2. Dynamic elections and ideological polarization

    Czech Academy of Sciences Publication Activity Database

    Nunnari, S.; Zápal, Jan

    2017-01-01

    Roč. 25, č. 4 (2017), s. 505-534 ISSN 1047-1987 Institutional support: Progres-Q24 Keywords : elections * political polarization Subject RIV: AH - Economics OBOR OECD: Economic Theory Impact factor: 3.361, year: 2016

  3. Dynamic elections and ideological polarization

    Czech Academy of Sciences Publication Activity Database

    Nunnari, S.; Zápal, Jan

    2017-01-01

    Roč. 25, č. 4 (2017), s. 505-534 ISSN 1047-1987 Institutional support: RVO:67985998 Keywords : elections * political polarization Subject RIV: AH - Economics OBOR OECD: Economic Theory Impact factor: 3.361, year: 2016

  4. Polarization at LEP. Vol. 2

    International Nuclear Information System (INIS)

    Alexander, G.; Altarelli, G.; Blondel, A.; Coignet, G.; Keil, E.; Plane, D.E.; Treille, D.

    1988-01-01

    This report contains a collection of papers covering the most important part of studies carried out by five study groups in view of a programme of experiments with polarized beams at LEP, the Large Electron-Positron collider under construction at CERN. The emphasis is on precision measurements at the Z peak. Such measurements are shown to be of considerable theoretical interest as well as very clean from the point of view of theoretical and experimental uncertainties. The measurement of the beam polarization can certainly be performed with sufficient accuracy, thanks to the availability of both e + and e - beam polarization. The normalization of the data taken with different beam helicities poses certain constraints that are described. Substantial progress has been made in understanding the possibility of providing longitudinally polarized beams in the LEP machine: The design of new wigglers and spin rotators, the study of correction procedures and results of numerical simulations are presented. (orig.)

  5. Mechanical writing of ferroelectric polarization.

    Science.gov (United States)

    Lu, H; Bark, C-W; Esque de los Ojos, D; Alcala, J; Eom, C B; Catalan, G; Gruverman, A

    2012-04-06

    Ferroelectric materials are characterized by a permanent electric dipole that can be reversed through the application of an external voltage, but a strong intrinsic coupling between polarization and deformation also causes all ferroelectrics to be piezoelectric, leading to applications in sensors and high-displacement actuators. A less explored property is flexoelectricity, the coupling between polarization and a strain gradient. We demonstrate that the stress gradient generated by the tip of an atomic force microscope can mechanically switch the polarization in the nanoscale volume of a ferroelectric film. Pure mechanical force can therefore be used as a dynamic tool for polarization control and may enable applications in which memory bits are written mechanically and read electrically.

  6. Mechanical Writing of Ferroelectric Polarization

    Science.gov (United States)

    Lu, H.; Bark, C.-W.; Esque de los Ojos, D.; Alcala, J.; Eom, C. B.; Catalan, G.; Gruverman, A.

    2012-04-01

    Ferroelectric materials are characterized by a permanent electric dipole that can be reversed through the application of an external voltage, but a strong intrinsic coupling between polarization and deformation also causes all ferroelectrics to be piezoelectric, leading to applications in sensors and high-displacement actuators. A less explored property is flexoelectricity, the coupling between polarization and a strain gradient. We demonstrate that the stress gradient generated by the tip of an atomic force microscope can mechanically switch the polarization in the nanoscale volume of a ferroelectric film. Pure mechanical force can therefore be used as a dynamic tool for polarization control and may enable applications in which memory bits are written mechanically and read electrically.

  7. Modeling optical and UV polarization of AGNs. IV. Polarization timing

    Science.gov (United States)

    Rojas Lobos, P. A.; Goosmann, R. W.; Marin, F.; Savić, D.

    2018-03-01

    Context. Optical observations cannot resolve the structure of active galactic nuclei (AGN), and a unified model for AGN was inferred mostly from indirect methods, such as spectroscopy and variability studies. Optical reverberation mapping allowed us to constrain the spatial dimension of the broad emission line region and thereby to measure the mass of supermassive black holes. Recently, reverberation was also applied to the polarized signal emerging from different AGN components. In principle, this should allow us to measure the spatial dimensions of the sub-parsec reprocessing media. Aim. We conduct numerical modeling of polarization reverberation and provide theoretical predictions for the polarization time lag induced by different AGN components. The model parameters are adjusted to the observational appearance of the Seyfert 1 galaxy NGC 4151. Methods: We modeled scattering-induced polarization and tested different geometries for the circumnuclear dust component. Our tests included the effects of clumpiness and different dust prescriptions. To further extend the model, we also explored the effects of additional ionized winds stretched along the polar direction, and of an equatorial scattering ring that is responsible for the polarization angle observed in pole-on AGN. The simulations were run using a time-dependent version of the STOKES code. Results: Our modeling confirms the previously found polarization characteristics as a function of the observer`s viewing angle. When the dust adopts a flared-disk geometry, the lags reveal a clear difference between type 1 and type 2 AGN. This distinction is less clear for a torus geometry where the time lag is more sensitive to the geometry and optical depth of the inner surface layers of the funnel. The presence of a scattering equatorial ring and ionized outflows increased the recorded polarization time lags, and the polar outflows smooths out dependence on viewing angle, especially for the higher optical depth of the

  8. Solid Polarized Targets and Applications

    International Nuclear Information System (INIS)

    Crabb, D. G.

    2008-01-01

    Examples are given of dynamically polarized targets in use today and how the subsystems have changed to meet the needs of todays experiments. Particular emphasis is placed on target materials such as ammonia and lithium deuteride. Recent polarization studies of irradiated materials such as butanol, deuterated butanol, polyethylene, and deuterated polyethylene are presented. The operation of two non-DNP target systems as well as applications of traditional DNP targets are briefly discussed

  9. Artificial anisotropy and polarizing filters.

    Science.gov (United States)

    Flory, François; Escoubas, Ludovic; Lazaridès, Basile

    2002-06-01

    The calculated spectral transmittance of a multilayer laser mirror is used to determine the effective index of the single layer equivalent to the multilayer stack. We measure the artificial anisotropy of photoresist thin films whose structure is a one-dimensional, subwavelength grating obtained from interference fringes. The limitation of the theory of the first-order effective index homogenization is discussed. We designed normal-incidence, polarizing coating and a polarization rotator by embedding anisotropic films in simple multilayer structures.

  10. Polarization bremsstrahlung in α decay

    International Nuclear Information System (INIS)

    Amusia, M. Ya.; Zon, B. A.; Kretinin, I. Yu.

    2007-01-01

    A mechanism of formation of electromagnetic radiation that accompanies α decay and is associated with the emission of photons by electrons of atomic shells due to the scattering of α particles by these atoms (polarization bremsstrahlung) is proposed. It is shown that, when the photon energy is no higher than the energy of K electrons of an atom, polarization bremsstrahlung makes a significant contribution to the bremsstrahlung in α decay

  11. Coherent states with elliptical polarization

    OpenAIRE

    Colavita, E.; Hacyan, S.

    2004-01-01

    Coherent states of the two dimensional harmonic oscillator are constructed as superpositions of energy and angular momentum eigenstates. It is shown that these states are Gaussian wave-packets moving along a classical trajectory, with a well defined elliptical polarization. They are coherent correlated states with respect to the usual cartesian position and momentum operators. A set of creation and annihilation operators is defined in polar coordinates, and it is shown that these same states ...

  12. Polarization of Coronal Forbidden Lines

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hao; Qu, Zhongquan [Yunnan Observatories, Chinese Academy of Sciences, Kunming, Yunnan 650011 (China); Landi Degl’Innocenti, Egidio, E-mail: sayahoro@ynao.ac.cn [Dipartimento di Astronomia e Scienza dello Spazio, Università di Firenze, Largo E. Fermi 2, I-50125 Firenze (Italy)

    2017-03-20

    Since the magnetic field is responsible for most manifestations of solar activity, one of the most challenging problems in solar physics is the diagnostics of solar magnetic fields, particularly in the outer atmosphere. To this end, it is important to develop rigorous diagnostic tools to interpret polarimetric observations in suitable spectral lines. This paper is devoted to analyzing the diagnostic content of linear polarization imaging observations in coronal forbidden lines. Although this technique is restricted to off-limb observations, it represents a significant tool to diagnose the magnetic field structure in the solar corona, where the magnetic field is intrinsically weak and still poorly known. We adopt the quantum theory of polarized line formation developed in the framework of the density matrix formalism, and synthesize images of the emergent linear polarization signal in coronal forbidden lines using potential-field source-surface magnetic field models. The influence of electronic collisions, active regions, and Thomson scattering on the linear polarization of coronal forbidden lines is also examined. It is found that active regions and Thomson scattering are capable of conspicuously influencing the orientation of the linear polarization. These effects have to be carefully taken into account to increase the accuracy of the field diagnostics. We also found that linear polarization observation in suitable lines can give valuable information on the long-term evolution of the magnetic field in the solar corona.

  13. Polarization in free electron lasers

    Energy Technology Data Exchange (ETDEWEB)

    Papadichev, V.A. [Lebedev Physical Institute, Moscow (Russian Federation)

    1995-12-31

    Polarization of electromagnetic radiation is required very often in numerous scientific and industrial applications: studying of crystals, molecules and intermolecular interaction high-temperature superconductivity, semiconductors and their transitions, polymers and liquid crystals. Using polarized radiation allows to obtain important data (otherwise inaccessible) in astrophysics, meteorology and oceanology. It is promising in chemistry and biology for selective influence on definite parts of molecules in chain synthesis reactions, precise control of various processes at cell and subcell levels, genetic engineering etc. Though polarization methods are well elaborated in optics, they can fail in far-infrared, vacuum-ultraviolet and X-ray regions because of lack of suitable non-absorbing materials and damaging of optical elements at high specific power levels. Therefore, it is of some interest to analyse polarization of untreated FEL radiation obtained with various types of undulators, with and without axial magnetic field. The polarization is studied using solutions for electron orbits in various cases: plane or helical undulator with or without axial magnetic field, two plane undulators, a combination of right- and left-handed helical undulators with equal periods, but different field amplitudes. Some examples of how a desired polarization (elliptical circular or linear) can be obtained or changed quickly, which is necessary in many experiments, are given.

  14. ESR and related experiments in spin-polarized atomic hydrogen

    International Nuclear Information System (INIS)

    Yperen, G.H. van.

    1984-01-01

    This thesis deals with some experiments in (gaseous) spin-polarized atomic hydrogen. One uses the expression 'stabilized' atomic hydrogen, meaning that by choosing suitable conditions one can suppress the tendency of atoms to recombine into H 2 molecules, such that the lifetime of the atomic state is extended by many orders of magnitude. Research is focused at the study of processes that determine the decay rate of polarized H samples, with the ultimate goal of preparing samples of sufficiently high density and at low enough temperature to observe experimentally the behaviour of the (degenerate) quantum gas. ESR (Electron Spin Resonance) appears to be a very suitable measurement technique to study the properties of polarized H. This work describes the introduction of ESR as detection technique, and the first results of an experiment in polarized H using this technique. (orig.)

  15. Polar bears: the fate of an icon.

    Science.gov (United States)

    Fitzgerald, Kevin T

    2013-11-01

    Polar bears are one of the most iconic animals on our planet. Worldwide, even people who would never see one are drawn to these charismatic arctic ice hunters. They are the world's largest terrestrial carnivore, and despite being born on land, they spend most of their lives out on the sea ice and are considered a marine mammal. Current global studies estimate there are around 20,000 animals in some 19 discrete circumpolar populations. Aside from pregnant females denning in the winter months to give birth, the white bears do not hibernate. They spend their winters on the sea ice hunting seals, an activity they are spectacularly adapted for. Research on these animals is incredibly difficult because of the inhospitable surroundings they inhabit and how inaccessible they make the bears. For many years, the sum of our understanding of the natural history of polar bears came from tracks, scats, the remains of their kills, abandoned dens, and anecdotal observations of native hunters, explorers, and early biologists. Nonetheless, the last 40 years have seen a much better picture of their biology emerge thanks to, first, dedicated Canadian researchers and, later, truly international efforts of workers from many countries. Veterinarians have contributed to our knowledge of the bears by delivering and monitoring anesthesia, obtaining blood samples, performing necropsies, investigating their reproduction, conducting radiotelemetry studies, and examining their behavior. Recently, new technologies have been developed that revolutionize the study of the lives and natural history of undisturbed polar bears. These advances include better satellite radiotelemetry equipment and the development of remote-controlled miniature devices equipped with high-definition cameras. Such new modalities provide dramatic new insights into the life of polar bears. The remarkable degree of specialized adaptation to life on the sea ice that allowed the bears to be successful is the very reason that

  16. Radiography and tomography with polarized neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Treimer, Wolfgang, E-mail: treimer@helmholtz-berlin.de [University of Applied Sciences, Beuth Hochschule für Technik Berlin, Department Mathematics Physics and Chemistry, Luxemburgerstr. 10, D-13353 Berlin (Germany); Helmholtz Zentrum für Materialien und Energie, Department G – GTOMO, Hahn-Meitner-Platz 1, D-14109 Berlin (Germany)

    2014-01-15

    Neutron imaging became important when, besides providing impressive radiographic and tomographic images of various objects, physical, quantification of chemical, morphological or other parameters could be derived from 2D or 3D images. The spatial resolution of approximately 50 µm (and less) yields real space images of the bulk of specimens with more than some cm{sup 3} in volume. Thus the physics or chemistry of structures in a sample can be compared with scattering functions obtained e.g. from neutron scattering. The advantages of using neutrons become more pronounced when the neutron spin comes into play. The interaction of neutrons with magnetism is unique due to their low attenuation by matter and because their spin is sensitive to magnetic fields. Magnetic fields, domains and quantum effects such as the Meissner effect and flux trapping can only be visualized and quantified in the bulk of matter by imaging with polarized neutrons. This additional experimental tool is gaining more and more importance. There is a large number of new fields that can be investigated by neutron imaging, not only in physics, but also in geology, archeology, cultural heritage, soil culture, applied material research, magnetism, etc. One of the top applications of polarized neutron imaging is the large field of superconductivity where the Meissner effect and flux pinning can be visualized and quantified. Here we will give a short summary of the results achieved by radiography and tomography with polarized neutrons. - Highlights: • Radiography and tomography with polarized neutrons yield new results concerning the suppressed Meissner effect and magnetic flux trapping. • Suppressed Meissner effect was observed in pure lead samples and niobium. • Trapped magnetic fields in cylindrical Pb samples are squeezed around the rod axis. • The shape and the amount of trapped fields could be determined and quantified.

  17. Superconducting polarizing magnet for a movable polarized target

    International Nuclear Information System (INIS)

    Anishchenko, N.G.; Bartenev, V.D.; Blinov, N.A.

    1998-01-01

    The superconducting polarizing magnet was constructed for the JINR (Dubna) movable polarized target (MPT) with working volume 200 mm long and 30 mm in diameter. The magnet provides a polarizing magnetic field up to 6 T in the centre with the uniformity of 4.5 x 10 -4 in the working volume of the target. The magnet contains a main solenoidal winding 558 mm long and 206/144 mm in diameters, and compensating and correcting winding placed at its ends. The windings are made of a NbTi wire, impregnated with the epoxy resin and placed in the horizontal cryostat. The diameter of the 'warm' aperture of the magnet cryostat is 96 mm. The design and technology of the magnet winding are described. Results of the magnetic field map measurements, using a NMR-magnetometer are given. A similar magnet constructed at DAPNIA, CEA/Saclay (France), represented a model for the present development. The MPT array is installed in the beam line of polarized neutrons produced by break-up of polarized deuterons extracted from the synchrophasotron of the Laboratory of High Energies (LHE), JINR (Dubna)

  18. Polarization fluctuations in stationary light beams

    International Nuclear Information System (INIS)

    Shevchenko, A.; Setaelae, T.; Kaivola, M.; Friberg, A.T.; Royal Institute of Technology , Department of Microelectronics and Applied Physics; Sweden)

    2009-01-01

    For stationary beams the degree of polarization contains only limited information on time dependent polarization. Two approaches towards assessing a beams polarization dynamics, one based on Poincare and the other on Jones vector formalism, are described leading to the notion of polarization time. Specific examples of partially temporally coherent electromagnetic beams are discussed. (Author)

  19. FIRST POLARIZED PROTON COLLISIONS AT RHIC

    International Nuclear Information System (INIS)

    ROSER, T.; AHRENS, L.; ALESSI, J.; BAI, M.; BEEBE-WANG, J.; BRENNAN, J.M.; BROWN, K.A.; BUNCE, G.; CAMERON, P.; COURANT, E.D.; DREES, A.; FISCHER, W.; FLILLER, R. III; GLENN, W.; HUANG, H.; LUCCIO, A.U.; MACKAY, W.W.; MAKDISI, Y.; MONTAG, C.; PILAT, F.; PTITSYN, V.; SATOGATA, T.

    2002-01-01

    We successfully injected polarized protons in both RHIC rings and maintained polarization during acceleration up to 100 GeV per ring using two Siberian snakes in each ring. Each snake consists of four helical superconducting dipoles which rotate the polarization by 180 o about a horizontal axis. This is the first time that polarized protons have been accelerated to 100 GeV

  20. Apico-basal polarity complex and cancer

    Indian Academy of Sciences (India)

    Apico-basal polarity is a cardinal molecular feature of adult eukaryotic epithelial cells and appears to be involved in several key cellular processes including polarized cell migration and maintenance of tissue architecture. Epithelial cell polarity is maintained by three well-conserved polarity complexes, namely, PAR, Crumbs ...

  1. Inclusive quasielastic scattering of polarized electrons from polarized nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Amaro, J.E. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Center for Theoretical Physics]|[Universidad de Granada (Spain). Dept. de Fisica Moderna]|[Massachusetts Inst. of Tech., Cambridge, MA (United States). Lab. for Nuclear Science]|[Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Physics; Caballero, J.A. [Consejo Superior de Investigaciones Cientificas (CSIC), Madrid (Spain). Inst. de Estructura de la Materia]|[Sevilla Univ. (Spain). Dept. de Fisica Atomica, Molecular y Nuclear; Donnelly, T.W. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Center for Theoretical Physics]|[Massachusetts Inst. of Tech., Cambridge, MA (United States). Lab. for Nuclear Science]|[Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Physics; Moya de Guerra, E. [Consejo Superior de Investigaciones Cientificas (CSIC), Madrid (Spain). Inst. de Estructura de la Materia

    1996-12-23

    The inclusive quasielastic response functions that appear in the scattering of polarized electrons from polarized nuclei are computed and analyzed for several closed-shell-minus-one nuclei with special attention paid to {sup 39}K. Results are presented using two models for the ejected nucleon - when described by a distorted wave in the continuum shell model or by a plane wave in PWIA with on- and off-shell nucleons. Relativistic effects in kinematics and in the electromagnetic current have been incorporated throughout. Specifically, the recently obtained expansion of the electromagnetic current in powers only of the struck nucleon`s momentum is employed for the on-shell current and the effects of the first-order terms (spin-orbit and convection) are compared with the zeroth-order (charge and magnetization) contributions. The use of polarized inclusive quasielastic electron scattering as a tool for determining near-valence nucleon momentum distributions is discussed. (orig.).

  2. System for measuring of proton polarization in polarized target

    International Nuclear Information System (INIS)

    Derkach, A.Ya.; Lukhanin, A.A.; Karnaukhov, I.M.; Kuz'menko, V.S.; Telegin, Yu.N.; Trotsenko, V.I.; Chechetenko, V.F.

    1981-01-01

    Measurement system of proton polarization in the target, which uses the method of nuclear magnetic resonance is described. To record the signal of NMR-absorption a parallel Q-meter of voltage with analogous subtraction of resonance characteristics of measurement circuit is used. To obtain gradual sensitivity of the system to polarization state in the whole volume of the target the measurement coils is made of tape conductor. The analysis and mathematical modelling of Q-meter are carried out. Corrections for nonlinearity and dispersion are calculated. Key diagrams of the main electron blocks of Q-meter are presented. The system described operates on line with the M6000 computer. Total error of measurement of polarization value of free protons in the target does not exceed 6% [ru

  3. System of measurement of proton polarization in a polarized target

    Energy Technology Data Exchange (ETDEWEB)

    Karnaukov, I.M.; Chechetenko, V.F.; Lukhanin, A.A.; Telegin, Y.N.; Trotsenko, V.I.

    1985-05-01

    This paper describes a nuclear magnetic resonance spectrometer with high sensitivity. The signal of NMR absorption is recorded by a Q-meter with a series circuit and a circuit for compensation of the resonance characteristic of the measuring circuit. In order to ensure uniform sensitivity of the system to the state of polarization throughout the volume of the target and to enhance the S/N ration the measuring coil is made of a flat conductor. The polarization-measuring system works on-line with an M-6000 computer. The total error of measurement of the polarization of free protons in a target with allowance for the error due to local depolarization of free protons in a target with allowance for the error due to local depolarization of the working substance under irradiation with an intense photon beam is less than or equal to 6%.

  4. Performance of the SLC polarized electron source with high polarization

    International Nuclear Information System (INIS)

    Clendenin, J.E.; Alley, R.K.; Aoyagi, H.

    1993-04-01

    For the 1992 operating cycle of the SLAC Linear Collider (SLC), the polarized electron source (PES) during its maiden run successfully met the pulse intensity and overall efficiency requirements of the SLC. However, the polarization of the bulk GaAs cathode was low (∼27%) and the pulse-to-pulse stability was marginal. We have shown that adequate charge for the SLC can be extracted from a strained layer cathode having P e ∼80% even though the quantum efficiency (QE) is - beam stability. The performance of the PES during the 1993 SLC operating cycle with these and other improvements is discussed

  5. PIPER: Primordial Inflation Polarization Explorer

    Science.gov (United States)

    Lazear, Justin; Benford, D.; Chuss, D.; Fixsen, D.; Hinderks, J.; Hinshaw, G.; Jhabvala, C.; Johnson, B.; Kogut, A.; Mirel, P.; Mosely, H.; Staguhn, J.; Wollack, E.; Weston, A.; Vlahacos, K.; Bennett, C.; Eimer, J.; Halpern, M.; Irwin, K.; Dotson, J.; Ade, P.; Tucker, C.

    2011-05-01

    The Primordial Inflation Polarization Explorer (PIPER) is a balloon-borne instrument to measure the polarization of the cosmic microwave background in search of the expected signature of primordial gravity waves excited during an inflationary epoch shortly after the Big Bang. PIPER consists of two co-aligned telescopes, one sensitive to the Q Stokes parameter and the other to U. Sky signals will be detected with 5120 transition edge sensor (TES) bolometers distributed in four rectangular close-packed arrays maintained at 100 mK. To maximize the sensitivity of the instrument, both telescopes are mounted within a single open bucket dewar and are maintained at 1.5 K throughout flight, with no ambient-temperature windows between the sky and the detectors. To mitigate the effects of systematic errors, the polarized sky signals will be modulated using a variable-delay polarization modulator. PIPER will observe at frequencies 200, 270, 350, and 600 GHz to separate the CMB from polarized dust emission within the Galaxy. A series of flights alternating between northern and southern hemisphere launch sites will produce nearly full-sky maps in Stokes I, Q, U, and V. I will discuss the current status and potential science returns from the PIPER project.

  6. Polar metals by geometric design

    Science.gov (United States)

    Kim, T. H.; Puggioni, D.; Yuan, Y.; Xie, L.; Zhou, H.; Campbell, N.; Ryan, P. J.; Choi, Y.; Kim, J.-W.; Patzner, J. R.; Ryu, S.; Podkaminer, J. P.; Irwin, J.; Ma, Y.; Fennie, C. J.; Rzchowski, M. S.; Pan, X. Q.; Gopalan, V.; Rondinelli, J. M.; Eom, C. B.

    2016-05-01

    Gauss’s law dictates that the net electric field inside a conductor in electrostatic equilibrium is zero by effective charge screening; free carriers within a metal eliminate internal dipoles that may arise owing to asymmetric charge distributions. Quantum physics supports this view, demonstrating that delocalized electrons make a static macroscopic polarization, an ill-defined quantity in metals—it is exceedingly unusual to find a polar metal that exhibits long-range ordered dipoles owing to cooperative atomic displacements aligned from dipolar interactions as in insulating phases. Here we describe the quantum mechanical design and experimental realization of room-temperature polar metals in thin-film ANiO3 perovskite nickelates using a strategy based on atomic-scale control of inversion-preserving (centric) displacements. We predict with ab initio calculations that cooperative polar A cation displacements are geometrically stabilized with a non-equilibrium amplitude and tilt pattern of the corner-connected NiO6 octahedra—the structural signatures of perovskites—owing to geometric constraints imposed by the underlying substrate. Heteroepitaxial thin-films grown on LaAlO3 (111) substrates fulfil the design principles. We achieve both a conducting polar monoclinic oxide that is inaccessible in compositionally identical films grown on (001) substrates, and observe a hidden, previously unreported, non-equilibrium structure in thin-film geometries. We expect that the geometric stabilization approach will provide novel avenues for realizing new multifunctional materials with unusual coexisting properties.

  7. NMR dispersion measurement of dynamic nuclear polarization

    International Nuclear Information System (INIS)

    Davies, K.; Cox, S.F.J.

    1978-01-01

    The feasibility of monitoring dynamic nuclear polarization from the NMR dispersive susceptibility is examined. Two prototype instruments are tested in a polarized proton target using organic target material. The more promising employs a tunnel diode oscillator, inside the target cavity, and should provide a precise polarization measurement working at a frequency far enough from the main resonance for the disturbance of the measured polarization to be negligible. Other existing methods for measuring target polarization are briefly reviewed. (author)

  8. Polarization in electron and proton beams

    International Nuclear Information System (INIS)

    Buon, J.

    1986-03-01

    One first introduces the concept of polarization for spin 1/2 particle beams and discusses properties of spin kinetics in a stationary magnetic field. Then the acceleration of polarized protons in synchrotrons is studied with emphasis on depolarization when resonances are crossed and on the cures for reducing it. Finally, transverse polarization of electrons in storage rings is discussed as an equilibrium between polarizing and depolarizing effects of synchrotron radiation. Means for obtaining longitudinal polarization are also treated

  9. Theory and analysis of a large field polarization imaging system with obliquely incident light.

    Science.gov (United States)

    Lu, Xiaotian; Jin, Weiqi; Li, Li; Wang, Xia; Qiu, Su; Liu, Jing

    2018-02-05

    Polarization imaging technology provides information about not only the irradiance of a target but also the polarization degree and angle of polarization, which indicates extensive application potential. However, polarization imaging theory is based on paraxial optics. When a beam of obliquely incident light passes an analyser, the direction of light propagation is not perpendicular to the surface of the analyser and the applicability of the traditional paraxial optical polarization imaging theory is challenged. This paper investigates a theoretical model of a polarization imaging system with obliquely incident light and establishes a polarization imaging transmission model with a large field of obliquely incident light. In an imaging experiment with an integrating sphere light source and rotatable polarizer, the polarization imaging transmission model is verified and analysed for two cases of natural light and linearly polarized light incidence. Although the results indicate that the theoretical model is consistent with the experimental results, the theoretical model distinctly differs from the traditional paraxial approximation model. The results prove the accuracy and necessity of the theoretical model and the theoretical guiding significance for theoretical and systematic research of large field polarization imaging.

  10. Frequency dependent polarization in blazars

    International Nuclear Information System (INIS)

    Bjoernsson, C.I.

    1984-10-01

    It is argued that the intrinsic frequency dependent polarization in blazars finds its most straightforward explanations in terms of a single rather than a multicomponent sourcemodel. In order to reproduce the observations, under the assumption that the emission mechanism is optically thin synchrotron radiation, both a well ordered magnetic field and an electron distribution with a sharp break or cuttoff are necessary. Non-uniform pitch angle distribution and/or environments where synchrotron losses are important are both conducive to producing strong frequency dependent polarization. Reasons are put forth as to why such conditions ar expected to occur in blazars. Two specific models are discussed in detail and it is shown that they are both able to produce strong frequency dependent polarization, even when the spectral index changes by a small amount only. (orig.)

  11. Report of the polarization group

    International Nuclear Information System (INIS)

    Ford, W.; Kondo, K.; Martin, F.; Manning, G.; Miller, D.; Prescott, C.

    1975-01-01

    The use of longitudinal polarization in the reaction e + e - → μ + μ - was studied. Modifications of the magnetic insertion which could reduce synchrotron radiation by two or more were considered. In addition, a specific design is suggested which incorporates the optimized magnetic configuration; it is assumed that no particle detection is necessary near the interaction vertex and the synchrotron radiation is ''dumped'' up - and downstream. Also considered were vacuum chambers in which the synchrotron radiation is absorbed locally so that shielded regions are provided for detectors near the interaction vertex. A scheme for rotating the polarization outside the experiment areas is detailed; in this way the design of experiments is greatly simplified. Local intense ionization of residual gas in the interaction region due to synchrotron radiation at the insertion was studied. Finally, some general considerations in the production and measurement of beam polarization are summarized. 2 figures

  12. Uses of laser optical pumping to produce polarized ion beams

    International Nuclear Information System (INIS)

    Anderson, L.W.

    1983-01-01

    Laser optical pumping can be used to produce polarized alkali atom beams or polarized alkali vapor targets. Polarized alkali atom beams can be converted into polarized alkali ion beams, and polarized alkali vapor targets can be used to produce polarized H - or 3 He - ion beams. In this paper the authors discuss how the polarized alkali atom beams and polarized alkali vapor targets are used to produce polarized ion beams with emphasis on the production of polarized negative ion beams

  13. Polarization-Dependent Multi-Functional Metamaterial as Polarization Filter, Transparent Wall and Circular Polarizer using Ring-Cross Resonator

    Directory of Open Access Journals (Sweden)

    Z. Zhang

    2017-09-01

    Full Text Available We propose a polarization-dependent multi-functional metamaterial using ring-cross resonator. Based on the analysis of surface current distributions induced by different polarized incidence, we demonstrate that the proposed metamaterial serves as a polarization filter, a transparent wall and a circular polarizer under different polarization normal incidence. Additionally, parameter analyses on the control of resonance are discussed to complementally explain the physical origin. Simulated results show that the proposed metamaterial functions as a polarization filter eliminating the x-polarization wave at 10.1 GHz and y-polarization wave at 14.3 GHz, a transparent wall transmitting both x-polarized and y-polarized incident waves at 12.6 GHz, and a broadband circular polarizer converting the +45° polarized (-45° polarized incident wave to the left (right handed circularly polarized wave from 10.8 to 12.8 GHz, respectively. Measured results agree well with the simulation and validate the performance of the proposed multifunctional metamaterial.

  14. Polarized electroluminescence from silicon nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Bagraev, Nikolay; Danilovsky, Eduard; Gets, Dmitry; Klyachkin, Leonid; Kudryavtsev, Andrey; Kuzmin, Roman; Malyarenko, Anna [Ioffe Physical-Technical Institute, 194021 St. Petersburg (Russian Federation); Mashkov, Vladimir [St. Petersburg State Polytechnical University, 195251 St. Petersburg (Russian Federation)

    2012-05-15

    We present the first findings of the circularly polarized electroluminescence (CPEL) from silicon nanostructures which are the p-type ultra-narrow silicon quantum well (Si-QW) confined by {delta}-barriers heavily doped with boron. The CPEL dependences on the forward current and lateral electric field show the circularly polarized light emission which appears to be caused by the exciton recombination through the negative-U dipole boron centers at the Si-QW-{delta}-barriers interface with the assistance of phosphorus donors. (copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  15. All-fiber polarization switch

    Science.gov (United States)

    Knape, Harald; Margulis, Walter

    2007-03-01

    We report an all-fiber polarization switch made out of silica-based microstructured fiber suitable for Q-switching all-fiber lasers. Nanosecond high-voltage pulses are used to heat and expand an internal electrode to cause λ/2-polarization rotation in less than 10 ns for 1.5 μm light. The 10 cm long component has an experimentally measured optical insertion loss of 0.2 dB and a 0-10 kHz repetition frequency capacity and has been durability tested for more than 109 pulses.

  16. The sensitivity of income polarization

    DEFF Research Database (Denmark)

    Hussain, Azhar

    2009-01-01

    This study looks at polarization and its components' sensitivity to assumptions about equivalence scales, income definition, ethical income distribution parameters, and the income accounting period. A representative sample of Danish individual incomes from 1984 to 2002 is utilised. Results show...... that polarization has increased over time, regardless of the applied measure, when the last part of the period is compared to the first part of the period; primary causes being increased inequality (alienation) and faster income growth among high incomes relative to those in the middle of the distribution...

  17. Graphics of polar figure; Graficado de figura polar

    Energy Technology Data Exchange (ETDEWEB)

    Macias B, L.R

    1991-11-15

    The objective of this work, is that starting from a data file coming from a spectra that has been softened, and of the one that have been generated its coordinates to project it in stereographic form, to create the corresponding polar figure making use of the Cyber computer of the ININ by means of the GRAPHOS package. This work only requires a Beta, Fi and Intensity (I) enter data file. It starts of the existence of a softened spectra of which have been generated already with these data, making use of some language that in this case was FORTRAN for the Cyber computer, a program is generated supported in the Graphos package that allows starting of a reading of the Beta, Fi, I file, to generate the points in a stereographic projection and that it culminates with the graph of the corresponding polar figure. The program will request the pertinent information that is wanted to capture in the polar figure just as: date, name of the enter file, indexes of the polar figure, number of levels, radio of the stereographic projection (cms.), crystalline system to which belongs the sample, name the neuter graph file by create and to add the own general data. (Author)

  18. A Fuzzy Computing Model for Identifying Polarity of Chinese Sentiment Words

    OpenAIRE

    Wang, Bingkun; Huang, Yongfeng; Wu, Xian; Li, Xing

    2015-01-01

    With the spurt of online user-generated contents on web, sentiment analysis has become a very active research issue in data mining and natural language processing. As the most important indicator of sentiment, sentiment words which convey positive and negative polarity are quite instrumental for sentiment analysis. However, most of the existing methods for identifying polarity of sentiment words only consider the positive and negative polarity by the Cantor set, and no attention is paid to th...

  19. Research Research

    African Journals Online (AJOL)

    Research. May 2014, Vol. 6, No. 1 AJHPE 33. Research. Currently, radiography students are faced with the challenge of having to learn factual information, while ... A descriptive exploratory research design was used to collect both ..... Creswell J. Research Design: Quantitative, Qualitative and Mixed Methods Approaches.

  20. VIIRS/J1 polarization narrative

    Science.gov (United States)

    Waluschka, Eugene; McCorkel, Joel; McIntire, Jeff; Moyer, David; McAndrew, Brendan; Brown, Steven W.; Lykke, Keith R.; Young, James B.; Fest, Eric; Butler, James; Wang, Tung R.; Monroy, Eslim O.; Turpie, Kevin; Meister, Gerhard; Thome, Kurtis J.

    2015-09-01

    The polarization sensitivity of the Visible/NearIR (VISNIR) bands in the Joint Polar Satellite Sensor 1 (J1) Visible Infrared Imaging Radiometer Suite (VIIRS) instrument was measured using a broadband source. While polarization sensitivity for bands M5-M7, I1, and I2 was less than 2.5 %, the maximum polarization sensitivity for bands M1, M2, M3, and M4 was measured to be 6.4 %, 4.4 %, 3.1 %, and 4.3 %, respectively with a polarization characterization uncertainty of less than 0.38%. A detailed polarization model indicated that the large polarization sensitivity observed in the M1 to M4 bands is mainly due to the large polarization sensitivity introduced at the leading and trailing edges of the newly manufactured VISNIR bandpass focal plane filters installed in front of the VISNIR detectors. This was confirmed by polarization measurements of bands M1 and M4 bands using monochromatic light. Discussed are the activities leading up to and including the two polarization tests, some discussion of the polarization model and the model results, the role of the focal plane filters, the polarization testing of the Aft-Optics-Assembly, the testing of the polarizers at the National Aeronautics and Space Administration's (NASA) Goddard center and at the National Institute of Science and Technology (NIST) facility and the use of NIST's Traveling Spectral Irradiance and Radiance responsivity Calibrations using Uniform Sources (T-SIRCUS) for polarization testing and associated analyses and results.

  1. VIIRS-J1 Polarization Narrative

    Science.gov (United States)

    Waluschka, Eugene; McCorkel, Joel; McIntire, Jeff; Moyer, David; McAndrew, Brendan; Brown, Steven W.; Lykke, Keith; Butler, James; Meister, Gerhard; Thome, Kurtis J.

    2015-01-01

    The VIS/NIR bands polarization sensitivity of Joint Polar Satellite Sensor 1 (JPSS1) Visible/Infrared Imaging Radiometer Suite (VIIRS) instrument was measured using a broadband source. While polarization sensitivity for bands M5-M7, I1, and I2 was less than 2.5%, the maximum polarization sensitivity for bands M1, M2, M3, and M4 was measured to be 6.4%, 4.4%, 3.1%, and 4.3%, respectively with a polarization characterization uncertainty of less than 0.3%. A detailed polarization model indicated that the large polarization sensitivity observed in the M1 to M4 bands was mainly due to the large polarization sensitivity introduced at the leading and trailing edges of the newly manufactured VISNIR bandpass focal plane filters installed in front of the VISNIR detectors. This was confirmed by polarization measurements of bands M1 and M4 bands using monochromatic light. Discussed are the activities leading up to and including the instruments two polarization tests, some discussion of the polarization model and the model results, the role of the focal plane filters, the polarization testing of the Aft-Optics-Assembly, the testing of the polarizers at Goddard and NIST and the use of NIST's T-SIRCUS for polarization testing and associated analyses and results.

  2. APECS: A Network for Polar Early Career Scientist Professional Development

    Science.gov (United States)

    Enderlin, E. M.

    2014-12-01

    The Association of Polar Early Career Researchers (APECS) is an international and interdisciplinary organization for undergraduate and graduate students, postdoctoral researchers, early faculty members, educators and others with interests in the polar regions, alpine regions and the wider Cryosphere. APECS is a scientific, non-profit organization with free individual membership that aims to stimulate research collaborations and develop effective future leaders in polar research, education, and outreach. APECS grew out of the 4th International Polar Year (2007-08), which emphasized the need to stimulate and nurture the next generation of scientists in order to improve the understanding and communication of the polar regions and its global connections. The APECS organizational structure includes a Council and an elected Executive Committee that are supported by a Directorate. These positions are open to all individual members through a democratic process. The APECS Directorate is funded by the Norwegian Research Council, the University of Tromsø and the Norwegian Polar Institute and is hosted by the University of Tromsø. Early career scientists benefit from a range of activities hosted/organized by APECS. Every year, numerous activities are run with partner organizations and in conjunction with major polar conferences and meetings. In-person and online panels and workshops focus on a range of topics, from developing field skills to applying for a job after graduate school. Career development webinars are hosted each fall and topical research webinars are hosted throughout the year and archived online (http://www.apecs.is). The APECS website also contains abundant information on polar news, upcoming conferences and meetings, and job postings for early career scientists. To better respond to members' needs, APECS has national/regional committees that are linked to the international overarching organization. Many of these committees organize regional meetings or

  3. Measurement of inclusive quasielastic scattering of polarized electrons from polarized 3He

    International Nuclear Information System (INIS)

    Woodward, C.E.; Beise, E.J.; Belz, J.E.; Carr, R.W.; Filippone, B.W.; Lorenzon, W.B.; McKeown, R.D.; Mueller, B.; O'Neill, T.G.; Dodson, G.; Dow, K.; Farkhondeh, M.; Kowalski, S.; Lee, K.; Makins, N.; Milner, R.; Thompson, A.; Tieger, D.; van den Brand, J.; Young, A.; Yu, X.; Zumbro, J.

    1990-01-01

    We report a measurement of the asymmetry in spin-dependent quasielastic scattering of longitudinally polarized electrons from a polarized 3 He gas target. This measurement represents the first demonstration of a new method for studying electromagnetic nuclear structure: the scattering of polarized electrons from a polarized nuclear target. The measured asymmetry is in good agreement with a Faddeev calculation and supports the picture of spin-dependent quasielastic scattering from polarized 3 He as predominantly scattering from a polarized neutron

  4. Hyperon polarization: theory and experiments

    Energy Technology Data Exchange (ETDEWEB)

    Magnin, J.; Simao, F.R.A.

    1996-01-01

    We give a brief review of the experimental situation concerning hyperon polarization. We mention also the current models developed to understand the experimental results and make some comments on some theoretical aspects contained in the Thomas precession model. (author). 8 ref.

  5. Tau physics with polarized beams

    Energy Technology Data Exchange (ETDEWEB)

    Daoudi, M.

    1995-11-01

    We present the first results on tau physics using polarized beams. These include measurements of the {tau} Michel parameters {xi} and {xi}{delta} and the {tau} neutrino helicity h{sub {nu}}. The measurements were performed using the SLD detector at the Stanford Linear Collider (SLC).

  6. Circular polarization observed in bioluminescence

    NARCIS (Netherlands)

    Wijnberg, Hans; Meijer, E.W.; Hummelen, J.C.; Dekkers, H.P.J.M.; Schippers, P.H.; Carlson, A.D.

    1980-01-01

    While investigating circular polarization in luminescence, and having found it in chemiluminescence, we have studied bioluminescence because it is such a widespread and dramatic natural phenomenon. We report here that left and right lanterns of live larvae of the fireflies, Photuris lucicrescens and

  7. Verum focus and polar questions

    Directory of Open Access Journals (Sweden)

    Ion Giurgea

    2012-11-01

    Full Text Available We argue that some word order phenomena in Romanian and Sardinian are the result of a checking operation in the left periphery involving verum focus (i.e. focus on the polarity component of the sentence. In particular, this operation accounts for some word order patterns found in polar questions. In Romanian, polarity fronting is realized as head-movement of (V+T to a higher peripheral head which bears a Focus-probe. This licenses VS orders for predications in which VS is not allowed as a neutral order (i-level predicates, iteratives, generics. In Sardinian, an entire phrase headed by the lexical predicate (verbal non-finite form or non-verbal predicate is fronted before the auxiliary. We argue that this order is obtained by two movement operations, head-raising of Aux to Foc and movement of the predicate phrase to SpecFoc. We also present the semantics of polarity focus, distinguishing several types of focus (informational, emphatic, contrastive.

  8. Free radicals and polarized targets

    Science.gov (United States)

    Bunyatova, E. I.

    2004-06-01

    Many free radicals were added to organic compounds in search of high proton and deuteron polarizations. Few found practical application. A short review is presented, and special attention is given to some stable nitroxyl radicals which have lately been admixed to organic compounds solid at room temperature, in particular to scintillators.

  9. Free radicals and polarized targets

    Energy Technology Data Exchange (ETDEWEB)

    Bunyatova, E.I. E-mail: bunyatel@nusun.jinr.ru

    2004-06-21

    Many free radicals were added to organic compounds in search of high proton and deuteron polarizations. Few found practical application. A short review is presented, and special attention is given to some stable nitroxyl radicals which have lately been admixed to organic compounds solid at room temperature, in particular to scintillators.

  10. History of the polarized beam

    Energy Technology Data Exchange (ETDEWEB)

    Parker, E F

    1979-01-01

    In 1973, the first high energy polarized proton beam was developed at the Argonne Zero Gradient Synchrotron (ZGS). It operated very successfully and productively until 1979 when the ZGS was shut down permanently. This report describes the development, characteristics, and operations of this facility.

  11. TREC Dynamic Domain: Polar Science

    Science.gov (United States)

    2015-11-20

    similarity. However, not all teams that submitted web crawls to this dataset applied their jaccard- similarity algorithms . 4.2 Data Format ...analysis. These algorithms were focused then on allowing better answers to the below representative science queries of our Polar data: 1. What...

  12. Bacteriophage in polar inland waters

    Science.gov (United States)

    Säwström, Christin; Lisle, John; Anesio, A.M.; Priscu, John C.; Laybourn-Parry, J.

    2008-01-01

    Bacteriophages are found wherever microbial life is present and play a significant role in aquatic ecosystems. They mediate microbial abundance, production, respiration, diversity, genetic transfer, nutrient cycling and particle size distribution. Most studies of bacteriophage ecology have been undertaken at temperate latitudes. Data on bacteriophages in polar inland waters are scant but the indications are that they play an active and dynamic role in these microbially dominated polar ecosystems. This review summarises what is presently known about polar inland bacteriophages, ranging from subglacial Antarctic lakes to glacial ecosystems in the Arctic. The review examines interactions between bacteriophages and their hosts and the abiotic and biotic variables that influence these interactions in polar inland waters. In addition, we consider the proportion of the bacteria in Arctic and Antarctic lake and glacial waters that are lysogenic and visibly infected with viruses. We assess the relevance of bacteriophages in the microbial loop in the extreme environments of Antarctic and Arctic inland waters with an emphasis on carbon cycling.

  13. High current polarized proton sources

    Energy Technology Data Exchange (ETDEWEB)

    Alessi, J.G.

    1988-01-01

    Polarized proton sources are now being used more frequently on linacs. In pulsed operation up to 10 mA of /rvec H//sup +/ and 0.4 mA of /rvec H//sup /minus// have been produced. The present status of these sources, and developments to reach even higher intensities, are reviewed. 39 refs., 1 tab.

  14. the effect of surface polarity

    Indian Academy of Sciences (India)

    Abstract. An implant material when comes in contact with blood fluids (e.g., blood and lymph), adsorb proteins spontaneously on its surface. Notably, blood coagulation is influenced by many factors, including mainly chemical structure and polarity (charge) of the material. The present study describes the methodology to ...

  15. Verum focus and polar questions

    Directory of Open Access Journals (Sweden)

    Ion Giurgea

    2012-01-01

    Full Text Available We argue that some word order phenomena in Romanian and Sardinian are the result of a checkingoperation in the left periphery involving verum focus (i.e. focus on the polarity component of the sentence.In particular, this operation accounts for some word order patterns found in polar questions. In Romanian,polarity fronting is realized as head-movement of (V+T to a higher peripheral head which bears a Focusprobe.This licenses VS orders for predications in which VS is not allowed as a neutral order (i-levelpredicates, iteratives, generics. In Sardinian, an entire phrase headed by the lexical predicate (verbal nonfiniteform or non-verbal predicate is fronted before the auxiliary. We argue that this order is obtained bytwo movement operations, head-raising of Aux to Foc and movement of the predicate phrase to SpecFoc. Wealso present the semantics of polarity focus, distinguishing several types of focus (informational, emphatic,contrastive.

  16. The SLC polarized electron source

    International Nuclear Information System (INIS)

    Clendenin, J.E.

    1990-10-01

    A polarized electron source consisting of a 3-electrode photocathode gun and a flashlamp-pumped dye laser has been designed and built for the SLC and is currently undergoing commissioning. The source is described, and the operating configuration is discussed. The present status of the source and future plans are briefly indicated. 7 refs., 4 figs

  17. Polar heating in Saturn's thermosphere

    Directory of Open Access Journals (Sweden)

    C. G. A. Smith

    2005-10-01

    Full Text Available A 3-D numerical global circulation model of the Kronian thermosphere has been used to investigate the influence of polar heating. The distributions of temperature and winds resulting from a general heat source in the polar regions are described. We show that both the total energy input and its vertical distribution are important to the resulting thermal structure. We find that the form of the topside heating profile is particularly important in determining exospheric temperatures. We compare our results to exospheric temperatures from Voyager occultation measurements (Smith et al., 1983; Festou and Atreya, 1982 and auroral H3+ temperatures from ground-based spectroscopic observations (e.g. Miller et al., 2000. We find that a polar heat source is consistent with both the Smith et al. determination of T∞~400 K at ~30° N and auroral temperatures. The required heat source is also consistent with recent estimates of the Joule heating rate at Saturn (Cowley et al., 2004. However, our results show that a polar heat source can probably not explain the Festou and Atreya determination of T∞~800 K at ~4° N and the auroral temperatures simultaneously. Keywords. Ionosphere (Planetary ionosphere – Magnetospherica physics (Planetary magnetospheres – Meterology and atmospheric dynamics (Thermospheric dynamics

  18. Researching research

    DEFF Research Database (Denmark)

    Pais, Alexandre; Valero, Paola

    2012-01-01

    We discuss contemporary theories in mathematics education in order to do research on research. Our strategy consists of analysing discursively and ideologically recent key publications addressing the role of theory in mathematics education research. We examine how the field fabricates its object...... of research by deploying Foucault’s notion of bio-politics - mainly to address the object “learning” - and Žižek’s ideology critique - to address the object “mathematics”. These theories, which have already been used in the field to research teaching and learning, have a great potential to contribute...... to a reflexivity of research on its discourses and effects. Furthermore, they enable us to present a clear distinction between what has been called the sociopolitical turn in mathematics education research and what we call a positioning of mathematics education (research) practices in the Political....

  19. Sentiment Polarization and Balance among Users in Online Social Networks

    DEFF Research Database (Denmark)

    Hillmann, Robert; Trier, Matthias

    2012-01-01

    by analyzing sentiment exchange within social networks from an ego-network perspective. We draw from research on social influence and social attachment to develop theories of node polarization, balance effects and sentiment mirroring within communication dyads. Our empirical analysis covers a multitude...

  20. Polarization-induced sigma-holes and hydrogen bonding

    Czech Academy of Sciences Publication Activity Database

    Hennemann, M.; Murray, J. S.; Politzer, P.; Riley, Kevin Eugene; Clark, T.

    2012-01-01

    Roč. 18, č. 6 (2012), s. 2461-2469 ISSN 1610-2940 Institutional research plan: CEZ:AV0Z40550506 Keywords : hydrogen bond * sigma-hole * polarization * field effect * ab initio calculation Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.984, year: 2012

  1. Studies of interactive plasma processes in the polar cusp

    Science.gov (United States)

    Waite, J. Hunter, Jr.

    1992-01-01

    The final report for NAGW-1657 (SwRI Project 15-2783) is presented. Several distinctly different areas of research are discussed: (1) studies of the thermal structure of polar outflows; (2) Prognoz-8 data analysis; and (3) the Ulysses Jupiter encounter.

  2. Persuasive Argumentation and Social Comparison as Determinants of Attitude Polarization

    Science.gov (United States)

    Burnstein, Eugene; Vinokur, Amiram

    1977-01-01

    Several studies, developed by the authors, indicate that persuasive-arguments theory by itself is an adequate explanation of polarization. Sanders and Baron (AA 526 863) criticize this research. Here the authors answer their critique. Relevant portions of the standard literature are reviewed to demonstrate that social comparison is neither a…

  3. A phenomenological theory for polarization flop in spiral multiferroic ...

    Indian Academy of Sciences (India)

    netoelectric coupling and a general ansatz for magnetization, the phenomenon of polarization flop has been ... sought phenomena for researchers because of their potential applications in spintronics and multiple state ..... A trial solution to the above nonlinear differential equation which satisfies boundary conditions (10) is.

  4. Institutions, employment insecurity and polarization in support for unemployment benefits

    NARCIS (Netherlands)

    Paskov, M.; Koster, F.

    2014-01-01

    Research has shown that workers’ support for public unemployment benefits (UB) depends on their level of employment insecurity: the insecure workers are more supportive of benefits than the secure workers. It can also be hypothesized that this polarization in support for UB is increased or decreased

  5. Polarized, compressed 3He-gas and its applications. Chapter 6

    International Nuclear Information System (INIS)

    Otten, E.

    1997-01-01

    Optical pumping of 3 He has been a subject of studies in atomic physics for very many years. With the advent of powerful pumping lasers it became possible and worthwhile to start a research and development program towards production of large quantities of spin polarized 3 He. Polarization preserving compression techniques as well as storage cells with relaxation times exceeding several days were developed. Production rates of order 1 bar liter/h were achieved at a polarization of about 50%. Such large amounts of spin polarized 3 He-gas are necessary and useful for interdisciplinary applications

  6. Demography and population status of polar bears in western Hudson Bay

    Science.gov (United States)

    Lunn, Nicholas J.; Regher, Eric V; Servanty, Sabrina; Converse, Sarah J.; Richardson, Evan S.; Stirling, Ian

    2013-01-01

    We evaluated the demography and population status of the Western Hudson Bay (WH) polar bear subpopulation for the period 1984-2011, using live-recapture data from research studies and management actions, and dead-recovery data from polar bears harvested for subsistence purposes or removed during human-bear conflicts.

  7. Spatial-frequency structure and polarization phasometry of coherent images of biological polycrystalline networks

    Science.gov (United States)

    Angelsky, Pavlo O.; Trifonyuk, L.

    2013-06-01

    Our research is aimed at designing an experimental method of Fourier laser polarization phasometry of the layers of human effusion for an express determining the potentialities of diagnostics of pathological changes in mammary gland basing on polarization analysis of laser images of the biopsy of the uterine wall tissue in order to differentiate benign (fibromioma) and malignant (adenocarcinoma).

  8. The polarized platypus polarized neutron reflectometry made possible

    International Nuclear Information System (INIS)

    Saerbeck, Thomas

    2009-01-01

    Full text: The magnetic moment of the neutron, together with it's highly penetrating non destructive manner, make polarized neutron reflectometry an excellent tool to study magnetic phenomena across surfaces and interfaces of thin films. Unlike other magnetometry techniques which ordinarily yield only average magnetization values or, in case of probes with higher spatial resolution (e.g. electron microscopy or scanning tunnelling microscopy), show a high surface sensitivity, PNR together with magnetic x-ray scattering provides the ability to spatially resolve vector magnetization well beneath the surface [1] The ability to obtain vector magnetization profiles across interfaces and surfaces of thin films and multilayers offers the intriguing possibility to study systematically magnetic configurations and magnetic exchange interactions through intervening layers. In this paper we present the performance of the new polarization system installed on the time of flight neutron reflectometer PLATYPUS at ANSTO's Bragg Institute. The spin state of the neutrons is polarized and analysed by spatial separation of different neutron spin states using polarizing Fe/Si supermirrors before, and after the sample stage. The supermirrors have a large wavelength acceptance bandwidth of 3 A to 12 A. To control the desired spin direction of the incoming and reflected beam from the sample, two sets of RF spin flippers are installed. In the free space between the spin flippers and the sample stage the neutron spin direction is maintained by two sets of magnetic guide field coils. The new sample environment for studies of magnetic samples includes a 1 T electromagnet and a closed cycle refrigerator which gives access to a temperature range from 4K to 3 50 K .

  9. Polarized few-nucleon targets: new developments

    International Nuclear Information System (INIS)

    Haeusser, O.

    1992-09-01

    We discuss recent improvements in producing polarized few-nucleon targets for nuclear and particle physics experiments. The emphasis is on progress with polarized gas targets intended for experiments at electron and proton storage rings. (author) 54 refs., 1 tab

  10. {tau} polarization in SUSY cascade decays

    Energy Technology Data Exchange (ETDEWEB)

    Choi, S.Y. [Chonbuk Univ., Jeonju (Korea), Dept. of Physics and RIPC]|[Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Hagiwara, K. [KEK National High Energy Physics, Tsukuba (Japan); Kim, Y.G. [Sejong Univ., Seoul (Korea). ARCSEC; Mawatari, K. [Korea Institute for Advanced Study, Seoul (Korea). School of Physics; Zerwas, P.M. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)]|[KEK National High Energy Physics, Tsukuba (Japan)

    2006-12-15

    {tau} leptons emitted in cascade decays of supersymmetric particles are polarized. The polarization may be exploited to determine spin and mixing properties of the neutralinos and stau particles involved. (orig.)

  11. Summary of the polarized beam working group

    International Nuclear Information System (INIS)

    Wienands, U.; Dyck, O. van.

    1989-05-01

    The polarized beam working group reviewed the AGS Bookster and TRIUMF KAON Factory facilities, heard an overview of the subject of siberian snakes, discussed internal polarized gas targets, and made recommendations for further study

  12. Functionalized liquid crystal polymers generate optical and polarization vortex beams

    Science.gov (United States)

    Sakamoto, Moritsugu; Nakamoto, Yuki; Tien, Tran Minh; Kawai, Kotaro; Noda, Kohei; Sasaki, Tomoyuki; Kawatsuki, Nobuhiro; Ono, Hiroshi

    2017-08-01

    In recent year, optical and polarization vortex (OV and PV) beams, which has phase and polarization singularities, have much-attracted attention in various research fields due to their unique physical properties. In this presentation, we report our attempts for the vortex beam generation based on the photo-alignment technique of functionalized liquid crystal polymers. The OV and PV beam generations are respectively demonstrated by using azo-dye-doped liquid crystal polymers and photocrosslinkable polymer liquid crystal. Our approaches realize highly functionalized vortex beam generators which are expected to evolve the photonics applications of vortex beams.

  13. Broadband RF Interferometric and Polarization Observations of Lightning Discharge Processes

    Science.gov (United States)

    Shao, X. M.; Ho, C.; Caffrey, M.; Graham, P.; Haynes, H.; Dingus, B.

    2017-12-01

    Broadband radio frequency interferometry was first introduced in 1996 for detailed lightning mapping studies [Shao et al., 1996], and the technique has since been improved significantly and has been increasingly widely used in the lightning research community. Due to continuously advancing data acquisition and computer capabilities, it is now possible to capture and process continuous broadband interferometer data for individual lightning flashes. In addition to the interferometric mapping of the lightning sources, we now introduce a broadband polarization capability that measures simultaneously the full polarization state of the corresponding broadband RF sources. Polarization observation provides another level of understanding of the discharge processes. For instance, a coherent breakdown process (e.g., relativistic runaway electron avalanches) is expected to produce highly polarized RF emissions, while an incoherent process related to thermal electrons is expected to produce randomly polarized RF emissions. For polarized emissions, the direction of the polarization is expected to aligned with the direction of the local electric field, and therefore can be used to understand the electric field structure at the breakdown locations. In the early summer of 2017, this new lightning system was tested in Los Alamos with a number of nearby lightning storms, and the system will be deployed in the late summer to the High Altitude Water Cherenkov Gamma-Ray Observatory (HAWC) on the flanks of the Sierra Negra volcano in Mexico at an altitude of 4.1km. HAWC is designed to observe high energy celestial gamma rays and cosmic rays with hundreds of water tanks. The goal of the collaborative lightning and HAWC observations is to understand the physics behind the lightning-related gamma-ray flashes (TGFs) and the initiation of the lightning discharges. We will report the new results from both the test observations and the HAWC observations. *Shao, X., D. Holden, and C. Rhodes

  14. Statistics of polarization speckle: theory versus experiment

    DEFF Research Database (Denmark)

    Wang, Wei; Hanson, Steen Grüner; Takeda, Mitsuo

    2010-01-01

    In this paper, we reviewed our recent work on the statistical properties of polarization speckle, described by stochastic Stokes parameters fluctuating in space. Based on the Gaussian assumption for the random electric field components and polar-interferometer, we investigated theoretically...... and experimentally the statistics of Stokes parameters of polarization speckle, including probability density function of Stokes parameters with the spatial degree of polarization, autocorrelation of Stokes vector and statistics of spatial derivatives for Stokes parameters....

  15. Some developments in polarized ion sources

    International Nuclear Information System (INIS)

    Witteveen, G.J.

    1979-01-01

    Investigations concerning an atomic beam source are presented and a new polarized ion source of a more universal type is introduced. Polarized and unpolarized beams of positively or negatively charged ions can be produced with this new version and the theoretical limits are a polarized negative hydrogen ion beam with an intensity of about 1 mH and a polarized proton beam with an intensity of 10 mH. (C.F.)

  16. Probing lateral magnetic nanostructures by polarized GISANS

    International Nuclear Information System (INIS)

    Kentzinger, E.; Frielinghaus, H.; Ruecker, U.; Ioffe, A.; Richter, D.; Brueckel, Th.

    2007-01-01

    While structural and magnetic lateral correlations in thin film materials can be investigated at the μm length scale by neutron off-specular scattering (OSS) with polarization analysis, they can also be investigated at the nm length scale by grazing incidence small-angle scattering of polarized neutrons (polarized GISANS). We exemplify this issue showing a combined OSS and GISANS study of the lateral correlations in a remanent polarizing supermirror

  17. Probing lateral magnetic nanostructures by polarized GISANS

    Science.gov (United States)

    Kentzinger, E.; Frielinghaus, H.; Rücker, U.; Ioffe, A.; Richter, D.; Brückel, Th.

    2007-07-01

    While structural and magnetic lateral correlations in thin film materials can be investigated at the μm length scale by neutron off-specular scattering (OSS) with polarization analysis, they can also be investigated at the nm length scale by grazing incidence small-angle scattering of polarized neutrons (polarized GISANS). We exemplify this issue showing a combined OSS and GISANS study of the lateral correlations in a remanent polarizing supermirror.

  18. Political Polarization and the Size of Government

    OpenAIRE

    Lindqvist, Erik; Östling, Robert

    2008-01-01

    We study the effect of political polarization on government spending and redistribution using the dispersion of self-reported political preferences as our measure of polarization. Politically polarized countries have lower levels of redistribution and government consumption. The relationship between political polarization and the size of government is stronger in democratic countries, indicating that the effect goes through the political system. The results are robust to a large set of contro...

  19. Baryon spectroscopy with polarization observables from CLAS

    Energy Technology Data Exchange (ETDEWEB)

    Strauch, Steffen [Univ. of South Carolina, Columbia, SC (United States)

    2016-08-01

    Meson photoproduction is an important tool in the study of baryon resonances. The spectrum of broad and overlapping nucleon excitations can be greatly clarified by use of polarization observables. The N* program at Jefferson Lab with the CEBAF Large Acceptance Spectrometer (CLAS) includes experimental studies with linearly and circularly polarized tagged photon beams, longitudinally and transversely polarized nucleon targets, and recoil polarizations. An overview of these experimental studies and recent results will be given.

  20. Silicon photonic thermometer operating on multiple polarizations

    DEFF Research Database (Denmark)

    Guan, Xiaowei; Wang, Xiaoyan; Frandsen, Lars Hagedorn

    2016-01-01

    A silicon photonics optical thermometer simultaneously operating on the multiple polarizations is designed and experimentally demonstrated. Measured sensitivities are 86pm/°C and 48pm/°C for the transverse-electric and transverse-magnetic polarizations, respectively.......A silicon photonics optical thermometer simultaneously operating on the multiple polarizations is designed and experimentally demonstrated. Measured sensitivities are 86pm/°C and 48pm/°C for the transverse-electric and transverse-magnetic polarizations, respectively....

  1. Polarization Measurements in the Vacuum Ultraviolet

    Science.gov (United States)

    West, E. A.; Kobayashi, K.; Noble, M.

    2005-01-01

    This paper will describe the VUV polarization testing of the NSSTC Solar Ultraviolet Magnetograph (SUMI) optics. SUMI is being developed for a sounding rocket payload to prove the feasibility of making magnetic field measurements in the transition region. This paper will cover the polarization properties of the VUV calibration polarizers, the instrumental polarization of the VUV chamber, SUMI's toroidal varied-line-space gratings and the SUMI polarimeter.

  2. RHIC Polarized proton performance in run-8

    International Nuclear Information System (INIS)

    Montag, C.; Bai, M.; MacKay, W.W.; Roser, T.; Abreu, N.; Ahrens, L.; Barton, D.; Beebe-Wang, J.; Blaskiewicz, M.; Brennan, J.M.; Brown, K.A.; Bruno, D.; Bunce, G.; Calaga, R.; Cameron, P.; Connolly, R.; D'Ottavio, T.; Drees, A.; Fedotov, A.V.; Fischer, W.; Ganetis, G.; Gardner, C.; Glenn, J.; Hayes, T.; Huang, H.; Ingrassia, P.; Kayran, D.A.; Kewisch, J.; Lee, R.C.; Lin, F.; Litvinenko, V.N.; Luccio, A.U.; Luo, Y.; Makdisi, Y.; Malitsky, N.; Marr, G.; Marusic, A.; Michnoff, R.; Morris, J.; Oerter, B.; Pilat, F.; Pile, P.; Robert-Demolaize, G.; Russo, T.; Satogata, T.; Schultheiss, C.; Sivertz, M.; Smith, K.; Tepikian, S.; Trbojevic, D.; Tsoupas, N.; Tuozzolo, J.; Zaltsman, A.; Zelenski, A.; Zeno, K.; Zhang, S.Y.

    2008-01-01

    During Run-8, the Relativistic Heavy Ion Collider (RHIC) provided collisions of spin-polarized proton beams at two interaction regions. Physics data were taken with vertical orientation of the beam polarization, which in the 'Yellow' RHIC ring was significantly lower than in previous years. We present recent developments and improvements as well as the luminosity and polarization performance achieved during Run-8, and we discuss possible causes of the not as high as previously achieved polarization performance of the 'Yellow' ring.

  3. Polarized Moessbauer transitions in mixed hyperfine interactions

    International Nuclear Information System (INIS)

    Barb, D.; Tarina, D.

    1975-01-01

    A contribution to the theory of elliptical polarization in the Moessbauer effect for transitions between mixed nuclear states is reported. A relation between the two-dimensional complex vector parameterization and the photon polarization density matrix was used in describing changes in the polarization of the gamma-ray involved. (A.K.)

  4. Sources of polarized ions and atoms

    International Nuclear Information System (INIS)

    Cornelius, W.D.

    1988-01-01

    In this presentation we discuss methods of producing large quantities of polarized atoms and ions (Stern-Gerlach separation, optical pumping, and spin-exchange) as well as experimental methods of measuring the degree of polarization of atomic systems. The usefulness of polarized atoms in probing the microscopic magnetic surface properties of materials will also be discussed. 39 refs., 5 figs., 2 tabs

  5. Configuration Manual Polarized Proton Collider at RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Alekseev, I.; Allgower, C.; Bai, M.; Batygin, Y.; Bozano, L.; Brown, K.; Bunce, G.; Cameron, P.; Courant, E.; Erin, S.; Escallier, J.; Fischer, W.; Gupta, R.; Hatanka, K.; Huang, H.; Imai, K.; Ishihara, M.; Jain, A.; Kanavets, V.; Katayama, T.; Kawaguchi, T.; Kelly, E.; Kurita, K.; Lee, S. Y.; Luccio, A.; MacKay, W. W.; Mahler, G.; Makdisi, Y.; Mariam, F.; McGahern, W.; Morgan, G.; Muratore, J.; Okamura, M.; Peggs, S.; Pilat, F.; Ptitsin, V.; Ratner, L.; Roser, T.; Saito, N.; Satoh, H.; Shatunov, Y.; Spinka, H.; Svirida, D.; Syphers, M.; Tepikian, S.; Tominaka, T.; Tsoupas, N.; Underwood, D.; Vasiliev, A.; Wanderer, P.; Willen, E.; Wu, H.; Yokosawa, A.; Zelenski, A.

    2006-01-01

    In this report we present our design to accelerate and store polarized protons in RHIC, with the level of polarization, luminosity, and control of systematic errors required by the approved RHIC spin physics program. We provide an overview of the physics to be studied using RHIC with polarized proton beams, and a brief description of the accelerator systems required for the project.

  6. DISCOVERY OF POLARIZATION REVERBERATION IN NGC 4151

    Energy Technology Data Exchange (ETDEWEB)

    Gaskell, C. Martin; Shoji, Masatoshi [Department of Physics and Astronomy, University of Nebraska, Lincoln, NE 68588-0111 (United States); Goosmann, Rene W. [Observatoire astronomique de Strasbourg, 11 rue de l' Universite, F-67000 Strasbourg (France); Merkulova, Nelly I.; Shakhovskoy, Nikolay M., E-mail: martin.gaskell@uv.cl, E-mail: mshoji@astro.as.utexas.edu, E-mail: rene.goosmann@astro.unistra.fr [Crimean Astrophysical Observatory, Nauchny, Crimea 98409 (Ukraine)

    2012-04-20

    Observations of the optical polarization of NGC 4151 in 1997-2003 show variations of an order of magnitude in the polarized flux while the polarization position angle remains constant. The amplitude of variability of the polarized flux is comparable to the amplitude of variability of the total U-band flux, except that the polarized flux follows the total flux with a lag of 8 {+-} 3 days. The time lag and the constancy of the position angle strongly favor a scattering origin for the variable polarization rather than a non-thermal synchrotron origin. The orientation of the position angle of the polarized flux (parallel to the radio axis) and the size of the lag imply that the polarization arises from electron scattering in a flattened region within the low-ionization component of the broad-line region. Polarization from dust scattering in the equatorial torus is ruled out as the source of the lag in polarized flux because it would produce a larger lag and, unless the half-opening angle of the torus is >53 Degree-Sign , the polarization would be perpendicular to the radio axis. We note a long-term change in the percentage of polarization at similar total flux levels, and this could be due either to changing non-axisymmetry in the optical continuum emission or a change in the number of scatterers on a timescale of years.

  7. Thin Scintillating Polarized Targets for Spin Physics

    Science.gov (United States)

    van den Brandt, B.; Bunyatova, E. I.; Hautle, P.; Konter, J. A.

    2003-07-01

    At PSI polarized scintillating targets are available since 1996. Proton polarizations of more than 80%, and deuteron polarizations of 25% in polystyrene-based scintillators can be reached under optimum conditions in a vertical dilution refrigerator with optical access, suited for nuclear and particle physics experiments. New preparation procedures allow to provide very thin polarizable scintillating targets and widen the spectrum of conceivable experiments.

  8. CONFIGURATION MANUAL POLARIZED PROTON COLLIDER AT RHIC.

    Energy Technology Data Exchange (ETDEWEB)

    ROSER,T.; MACKAY,W.W.; ALEKSEEV,I.; BAI,M.; BROWN,K.; BUNCE,G.; CAMERON,P.; COURANT,E.; ET AL.

    2001-03-01

    In this report, the authors present their design to accelerate and store polarized protons in RHIC, with the level of polarization, luminosity, and control of systematic errors required by the approved RHIC spin physics program. They provide an overview of the physics to be studied using RHIC with polarized proton beams, and a brief description of the accelerator systems required for the project.

  9. Kramers-Kronig relations for interstellar polarization

    International Nuclear Information System (INIS)

    Martin, P.G.

    1975-01-01

    The difficulties encountered in using the Kramers-Kronig relations to predict the behavior of interstellar polarization are pointed out, while at the same time their value in an interpretive role is acknowledged. Observations of interstellar circular polarization lead to restrictions on the interstellar grain composition, and additional constraints should be possible through measurement of linear polarization in the infrared and the ultraviolet

  10. Partial Polarization in Interfered Plasmon Fields

    Directory of Open Access Journals (Sweden)

    P. Martínez Vara

    2014-01-01

    Full Text Available We describe the polarization features for plasmon fields generated by the interference between two elemental surface plasmon modes, obtaining a set of Stokes parameters which allows establishing a parallelism with the traditional polarization model. With the analysis presented, we find the corresponding coherence matrix for plasmon fields incorporating to the plasmon optics the study of partial polarization effects.

  11. Apico-basal polarity complex and cancer

    Indian Academy of Sciences (India)

    2014-01-27

    Jan 27, 2014 ... and regulated by several polarity proteins. These polarity pro- teins are often targeted by EMT inducers, leading to their altered function, ultimately facilitating cell migration (Martin-Belmonte and Perez-Moreno 2012). EMT-related alterations include over- expression or deregulation of components of polarity ...

  12. Microwave-gated dynamic nuclear polarization

    DEFF Research Database (Denmark)

    Bornet, Aurélien; Pinon, Arthur; Jhajharia, Aditya

    2016-01-01

    Dissolution dynamic nuclear polarization (D-DNP) has become a method of choice to enhance signals in nuclear magnetic resonance (NMR). Recently, we have proposed to combine cross-polarization (CP) with D-DNP to provide high polarization P((13)C) in short build-up times. In this paper, we show...

  13. Fractal analysis of polar bear hairs

    Directory of Open Access Journals (Sweden)

    Wang Qing-Li

    2015-01-01

    Full Text Available Hairs of a polar bear (Ursus maritimus are of superior properties such as the excellent thermal protection. Why do polar bears can resist such cold environment? The paper concludes that its fractal porosity plays an important role, and its fractal dimensions are very close to the golden mean, 1.618, revealing the possible optimal structure of polar bear hair.

  14. Field theory of polar continua

    International Nuclear Information System (INIS)

    Heinz, C.

    1988-01-01

    A Lagrangian density in the polar space X 1+3+3 depending of the potentials and their derivativs and of the fluxes is introduced. The potentials are then the mechanical and electromagnetic potentials, the potentials of gravity and in the polar space X 1+3+3 the components of affine connection. The fluxes are essentially the tangential motors of the mechanical and electromagnetic world-lines multiplied with the density of mass and electric charge. The Hamilton principle gives, with the in variational calculus usual integrations by part, here done via the theorem of Gauss, the equations of motion and the field equations. The conditions of integrability for these equations are discussed. (author)

  15. How campaigns polarize the electorate

    DEFF Research Database (Denmark)

    Hansen, Kasper Møller; Kosiara-Pedersen, Karina

    2015-01-01

    The minimal effect theory of campaign studies stipulates that intense political competition during campaigns assures and reinforces the initial party choice of the electorate. We find that this reinforcement is two-fold. During the campaign, the party preference of the voters’ in-group party...... an increase in their preference for their most preferred party and a decrease for their least liked party as the campaign progresses. These trends show that the political campaign polarizes the electorate by increasing the affective distance between in-group party and out-group party preferences, thereby...... resulting in stronger political polarization after the campaign than before the campaign. The data utilized in this study is a large six-wave panel-study of Danish voters’ party preferences during the Danish parliamentary election of 2011. Thus, the analysis provides evidence of the minimal effect theory...

  16. Nuclear spin polarization of targets

    International Nuclear Information System (INIS)

    Happer, W.

    1990-01-01

    Lasers can be used to produce milligrams to grams of noble gas nuclei with spin polarizations in excess of 50%. These quantities are sufficient to be very useful targets in nuclear physics experiments. Alkali-metal atoms are used to capture the angular momentum of circularly polarized laser photons, and the alkali-metal atoms transfer their angular momentum to noble gas atoms in binary or three-body collisions. Non-radiative collisions between the excited alkali atoms and molecular quenching gases are essential to avoid radiation trapping. The spin exchange can involve gas-phase van der Waals molecules, consisting of a noble gas atom and an alkali metal atom. Surface chemistry is also of great importance in determining the wall-induced relaxation rates of the noble gases

  17. Accelerating polarized beams in Tevatron

    International Nuclear Information System (INIS)

    Teng, L.C.

    1989-02-01

    In this paper, we will examine the totality of equipment, manpower and cost necessary to obtain a polarized proton beam in the Tevatron. We will not, however, be concerned with the acquisition and acceleration of polarized /bar p/ beams. Furthermore we will consider only a planar main ring without overpass, although it is expected that Siberian snake schemes could be made to apply equally well to non-planar machines. In addition to not wanting to tackle here the task of reformulating the theory for a non-planar closed orbit, we also anticipate that as part of the Tevatron upgrade the main ring will in the not too distant future, be replaced by a planar main injector situated in a separate tunnel. 4 refs., 11 figs., 1 tab

  18. The ILC polarized electron source

    CERN Document Server

    Brachmann, Axel; Garwin, Edward; Kirby, Robert; Luh Dah An; Maruyama, Takashi; Prepost, Richard; Schultz, David; Sheppard, John

    2005-01-01

    The SLC polarized electron source (PES) can meet the expected requirements of the International Linear Collider (ILC) for polarization, charge and lifetime. However, experience with newer and successful PES designs at JLAB, Mainz and elsewhere can be incorporated into a first-generation ILC source that will emphasize reliability and stability without compromising the photocathode performance. The long pulse train for the ILC may introduce new challenges for the PES, and in addition more reliable and stable operation of the PES may be achievable if appropriate R&D is carried out for higher voltage operation and for a simpler load-lock system. The outline of the R&D program currently taking shape at SLAC and elsewhere is discussed. The principal components of the proposed ILC PES, including the laser system necessary for operational tests, are described.

  19. Surface Polarization Effects on Ion-Containing Emulsions

    Science.gov (United States)

    Shen, Meng; Li, Honghao; Olvera de la Cruz, Monica

    2017-09-01

    Surface polarization in ion-containing heterogeneous dielectric media such as cell media and emulsions is determined by and determines the positions of the ions. We compute the surface polarization self-consistently as the ions move and analyze their effects on the interactions between electro-neutral, ion-containing droplets using coarse-grained molecular dynamics simulations based on the true energy functional. For water droplets immersed in oil, the interdroplet interaction is attractive, and the surface polarization makes the major contribution. By contrast, for oil droplets in water, the ion-surface induced charge interaction is repulsive and counteracts the attraction between the ions, leading to a small attractive interaction between the droplets. This research improves our understanding of self-assembly in mixed phases such as metal extraction for recovering rare earth elements and nuclear waste as well as water purification.

  20. Moral opinion polarization and the erosion of trust.

    Science.gov (United States)

    Rapp, Carolin

    2016-07-01

    Since Puntam's seminal work on declining levels of social capital, the question of how social trust is formed has reached unprecedented heights of critical enquiry. While most of the current research concentrates on ethnic diversity and income inequality as the main influences driving down generalized trust, we focus on opinion polarization as another potential impact factor on trust. In more detail, we investigate the extent to which polarization over morally charged issues such as homsexuality, abortion and euthanasia affects individuals' likelihood to trust others. We hypothesize that moral issues have a natural tendency to divide societies' opinions into opposing poles and, thus, to challenge social cohesion in modern civil societies. Based on hierarchical analyses of the fifth wave of the World Values Survey (WVS) - comprising a sample of 39 countries - our results reveal that individuals living in countries characterized by more opinion polarization tend to have less trust in other people. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Polarized Emission from Gamma-Ray Burst Jets

    Directory of Open Access Journals (Sweden)

    Shiho Kobayashi

    2017-11-01

    Full Text Available I review how polarization signals have been discussed in the research field of Gamma-Ray Bursts (GRBs. I mainly discuss two subjects in which polarimetry enables us to study the nature of relativistic jets. (1 Jet breaks: Gamma-ray bursts are produced in ultra-relativistic jets. Due to the relativistic beaming effect, the emission can be modeled in a spherical model at early times. However, as the jet gradually slows down, we begin to see the edge of the jet together with polarized signals at some point. (2 Optical flash: later time afterglow is known to be insensitive to the properties of the original ejecta from the GRB central engine. However, a short-lived, reverse shock emission would enable us to study the nature of of GRB jets. I also briefly discuss the recent detection of optical circular polarization in GRB afterglow.

  2. High-energy nuclear optics of polarized particles

    CERN Document Server

    Baryshevsky, Vladimir G

    2012-01-01

    The various phenomena caused by refraction and diffraction of polarized elementary particles in matter have opened up a new research area in the particle physics: nuclear optics of polarized particles. Effects similar to the well-known optical phenomena such as birefringence and Faraday effects, exist also in particle physics, though the particle wavelength is much less than the distance between atoms of matter. Current knowledge of the quasi-optical effects, which exist for all particles in any wavelength range (and energies from low to extremely high), will enable us to investigate different properties of interacting particles (nuclei) in a new aspect. This pioneering book will provide detailed accounts of quasi-optical phenomena in the particle polarization, and will interest physicists and professionals in experimental particle physics.

  3. Rotating scanning polarization profile monitor

    Energy Technology Data Exchange (ETDEWEB)

    Soukup, J.; Green, P.W.; Holm, L.; Korkmaz, E.; Mullin, S.; Roy, G.; Stocki, a.T. [Dept. of Physics, University of Alberta, Edmonton, AB, T6G 2N5 (Canada); Berdoz, A.R.; Birchal, J.; Campbell, J.R.; Hamian, A.A.; Page, S.A.; Ramsay, W.D.; Reitzner, S.D.; Sekulovich, A.M.; van Oers, a.W.T.H. [Dept. of Physics, University of Manitoba, Winnipeg, MB, R3T 2N2 (Canada); Bowman, J.D.; Mischke, R.E. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Davis, C.A.; Healey, D.C.; Helmer, R.; Levy, C.D.P.; Schmor, a.P.W. [TRIUMF, 4004 Wesbrook Mall, Vancouver, BC, V6T 2A3 (Canada); Titov, N.A.; Zelenskii, A.N. [Institute for Nuclear Research, Russian Academy of Sciences, Moscow, SU 117312 (Russian Federation)

    1995-05-05

    A polarimeter capable of determining transverse component polarization profile of the 222 MeV proton beam both in horizontal ({ital x}) and vertical ({ital y}) directions with faster than 1 Hz scanning frequency has been developed and built as part of the preparations in the TRIUMF Experiment 497 measuring the flavour conserving hadronic weak interaction (parity violation measurement). The design features and test performance results are presented. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

  4. Polarization phenomena in quantum chromodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Brodsky, S.J. [Stanford Univ., CA (United States)

    1994-12-01

    The author discusses a number of interrelated hadronic spin effects which test fundamental features of perturbative and nonperturbative QCD. For example, the anomalous magnetic moment of the proton and the axial coupling g{sub A} on the nucleon are shown to be related to each other for fixed proton radius, independent of the form of the underlying three-quark relativistic quark wavefunction. The renormalization scale and scheme ambiguities for the radiative corrections to the Bjorken sum rule for the polarized structure functions can be eliminated by using commensurate scale relations with other observables. Other examples include (a) new constraints on the shape and normalization of the polarized quark and gluon structure functions of the proton at large and small x{sub bj}; (b) consequences of the principle of hadron retention in high x{sub F} inclusive reactions; (c) applications of hadron helicity conservation to high momentum transfer exclusive reactions; and (d) the dependence of nuclear structure functions and shadowing on virtual photon polarization. The author also discusses the implications of a number of measurements which are in striking conflict with leading-twist perturbative QCD predictions, such as the extraordinarily large spin correlation A{sub NN} observed in large angle proton-proton scattering, the anomalously large {rho}{pi} branching ratio of the J/{psi}, and the rapidly changing polarization dependence of both J/{psi} and continuum lepton pair hadroproduction observed at large x{sub F}. The azimuthal angular dependence of the Drell-Yan process is shown to be highly sensitive to the projectile distribution amplitude, the fundamental valence light-cone wavefunction of the hadron.

  5. Scattering Polarization in Solar Flares

    Czech Academy of Sciences Publication Activity Database

    Štěpán, Jiří; Heinzel, Petr

    2013-01-01

    Roč. 778, č. 1 (2013), L6/1-L6/6 ISSN 2041-8205 R&D Projects: GA ČR GAP209/12/1652; GA ČR GPP209/12/P741 Institutional support: RVO:67985815 Keywords : line formation * polarization * radiative transfer Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 5.602, year: 2013

  6. Vacuum polarization and Hawking radiation

    Science.gov (United States)

    Rahmati, Shohreh

    Quantum gravity is one of the interesting fields in contemporary physics which is still in progress. The purpose of quantum gravity is to present a quantum description for spacetime at 10-33cm or find the 'quanta' of gravitational interaction.. At present, the most viable theory to describe gravitational interaction is general relativity which is a classical theory. Semi-classical quantum gravity or quantum field theory in curved spacetime is an approximation to a full quantum theory of gravity. This approximation considers gravity as a classical field and matter fields are quantized. One interesting phenomena in semi-classical quantum gravity is Hawking radiation. Hawking radiation was derived by Stephen Hawking as a thermal emission of particles from the black hole horizon. In this thesis we obtain the spectrum of Hawking radiation using a new method. Vacuum is defined as the possible lowest energy state which is filled with pairs of virtual particle-antiparticle. Vacuum polarization is a consequence of pair creation in the presence of an external field such as an electromagnetic or gravitational field. Vacuum polarization in the vicinity of a black hole horizon can be interpreted as the cause of the emission from black holes known as Hawking radiation. In this thesis we try to obtain the Hawking spectrum using this approach. We re-examine vacuum polarization of a scalar field in a quasi-local volume that includes the horizon. We study the interaction of a scalar field with the background gravitational field of the black hole in the desired quasi-local region. The quasi-local volume is a hollow cylinder enclosed by two membranes, one inside the horizon and one outside the horizon. The net rate of particle emission can be obtained as the difference of the vacuum polarization from the outer boundary and inner boundary of the cylinder. Thus we found a new method to derive Hawking emission which is unitary and well defined in quantum field theory.

  7. Physics results from polarized DIS

    International Nuclear Information System (INIS)

    Ramsey, G. P.

    1998-01-01

    We have extracted polarized nucleon distributions from recent data at CERN, SLAC and DESY. The flavor-dependent valence and sea quark spin distributions are determined for each experiment. We take into account possible differences in the up and down sea distributions, and assume that the strange sea contribution is suppressed by mass effects. Physics results determined from different experiments are compared, including higher order corrections

  8. Physics results from polarized DIS.

    Energy Technology Data Exchange (ETDEWEB)

    Ramsey, G. P.

    1998-03-23

    We have extracted polarized nucleon distributions from recent data at CERN, SLAC and DESY. The flavor-dependent valence and sea quark spin distributions are determined for each experiment. We take into account possible differences in the up and down sea distributions, and assume that the strange sea contribution is suppressed by mass effects. Physics results determined from different experiments are compared, including higher order corrections.

  9. Potentiometric titration with polarized electrodes

    International Nuclear Information System (INIS)

    Chikryzova, E.G.

    1977-01-01

    Based on the analysis of the works carried out during 1911-75 consideration is given to the present state of the method of potentiometric titration with polarized electrodes. The material is generalized in the tabular form indicating the elments of interest, titration conditions and the objects to be analyzed. The list and classification of the potentiometric titration methods intended for determining organic and inorganic substances are presented

  10. The State and Future of Mars Polar Science and Exploration

    Science.gov (United States)

    Clifford, Stephen M.; Crisp, David; Fisher, David A.; Herkenhoff, Ken E.; Smrekar, Suzanne E.; Thomas, Peter C.; Wynn-Williams, David D.; Zurek, Richard W.; Barnes, Jeffrey R.; Bills, Bruce G.

    2000-01-01

    As the planet's principal cold traps, the martian polar regions have accumulated extensive mantles of ice and dust that cover individual areas of approx. 10(exp 6)sq km and total as much as 3-4 km thick. From the scarcity of superposed craters on their surface, these layered deposits are thought to he comparatively young-preserving a record of the seasonal and climatic cycling of atmospheric CO2, H2O, and dust over the past approx. 10(exp 5)-10(exp 8) years. For this reason, the martian polar deposits may serve as a Rosetta Stone for understanding the geologic and climatic history of the planet-documenting variations in insolation (due to quasiperiodic oscillations in the planet's obliquity and orbital elements), volatile mass balance, atmospheric composition, dust storm activity, volcanic eruptions, large impacts, catastrophic floods, solar luminosity, supernovae, and perhaps even a record of microbial life. Beyond their scientific value, the polar regions may soon prove important for another reason-providing a valuable and accessible reservoir of water to support the long-term human exploration of Mars. In this paper we assess the current state of Mars polar research, identify the key questions that motivate the exploration of the polar regions, discuss the extent to which current missions will address these questions, and speculate about what additional capabilities and investigations may be required to address the issues that remain outstanding.

  11. Corporate funding and ideological polarization about climate change

    Science.gov (United States)

    Farrell, Justin

    2016-01-01

    Drawing on large-scale computational data and methods, this research demonstrates how polarization efforts are influenced by a patterned network of political and financial actors. These dynamics, which have been notoriously difficult to quantify, are illustrated here with a computational analysis of climate change politics in the United States. The comprehensive data include all individual and organizational actors in the climate change countermovement (164 organizations), as well as all written and verbal texts produced by this network between 1993–2013 (40,785 texts, more than 39 million words). Two main findings emerge. First, that organizations with corporate funding were more likely to have written and disseminated texts meant to polarize the climate change issue. Second, and more importantly, that corporate funding influences the actual thematic content of these polarization efforts, and the discursive prevalence of that thematic content over time. These findings provide new, and comprehensive, confirmation of dynamics long thought to be at the root of climate change politics and discourse. Beyond the specifics of climate change, this paper has important implications for understanding ideological polarization more generally, and the increasing role of private funding in determining why certain polarizing themes are created and amplified. Lastly, the paper suggests that future studies build on the novel approach taken here that integrates large-scale textual analysis with social networks. PMID:26598653

  12. Corporate funding and ideological polarization about climate change.

    Science.gov (United States)

    Farrell, Justin

    2016-01-05

    Drawing on large-scale computational data and methods, this research demonstrates how polarization efforts are influenced by a patterned network of political and financial actors. These dynamics, which have been notoriously difficult to quantify, are illustrated here with a computational analysis of climate change politics in the United States. The comprehensive data include all individual and organizational actors in the climate change countermovement (164 organizations), as well as all written and verbal texts produced by this network between 1993-2013 (40,785 texts, more than 39 million words). Two main findings emerge. First, that organizations with corporate funding were more likely to have written and disseminated texts meant to polarize the climate change issue. Second, and more importantly, that corporate funding influences the actual thematic content of these polarization efforts, and the discursive prevalence of that thematic content over time. These findings provide new, and comprehensive, confirmation of dynamics long thought to be at the root of climate change politics and discourse. Beyond the specifics of climate change, this paper has important implications for understanding ideological polarization more generally, and the increasing role of private funding in determining why certain polarizing themes are created and amplified. Lastly, the paper suggests that future studies build on the novel approach taken here that integrates large-scale textual analysis with social networks.

  13. The State and Future of Mars Polar Science and Exploration

    Science.gov (United States)

    Clifford, S.M.; Crisp, D.; Fisher, D.A.; Herkenhoff, K. E.; Smrekar, S.E.; Thomas, P.C.; Wynn-Williams, D. D.; Zurek, R.W.; Barnes, J.R.; Bills, B.G.; Blake, E.W.; Calvin, W.M.; Cameron, J.M.; Carr, M.H.; Christensen, P.R.; Clark, B. C.; Clow, G.D.; Cutts, J.A.; Dahl-Jensen, D.; Durham, W.B.; Fanale, F.P.; Farmer, J.D.; Forget, F.; Gotto-Azuma, K.; Grard, R.; Haberle, R.M.; Harrison, W.; Harvey, R.; Howard, A.D.; Ingersoll, A.P.; James, P.B.; Kargel, J.S.; Kieffer, H.H.; Larsen, J.; Lepper, K.; Malin, M.C.; McCleese, D.J.; Murray, B.; Nye, J.F.; Paige, D.A.; Platt, S.R.; Plaut, J.J.; Reeh, N.; Rice, J.W.; Smith, D.E.; Stoker, C.R.; Tanaka, K.L.; Mosley-Thompson, E.; Thorsteinsson, T.; Wood, S.E.; Zent, A.; Zuber, M.T.; Zwally, H.J.

    2000-01-01

    As the planet's principal cold traps, the martian polar regions have accumulated extensive mantles of ice and dust that cover individual areas of ???106 km2 and total as much as 3-4 km thick. From the scarcity of superposed craters on their surface, these layered deposits are thought to be comparatively young - preserving a record of the seasonal and climatic cycling of atmospheric CO2, H2O, and dust over the past ???105-108 years. For this reason, the martian polar deposits may serve as a Rosetta Stone for understanding the geologic and climatic history of the planet - documenting variations in insolation (due to quasiperiodic oscillations in the planet's obliquity and orbital elements), volatile mass balance, atmospheric composition, dust storm activity, volcanic eruptions, large impacts, catastrophic floods, solar luminosity, supernovae, and perhaps even a record of microbial life. Beyond their scientific value, the polar regions may soon prove important for another reason - providing a valuable and accessible reservoir of water to support the long-term human exploration of Mars. In this paper we assess the current state of Mars polar research, identify the key questions that motivate the exploration of the polar regions, discuss the extent to which current missions will address these questions, and speculate about what additional capabilities and investigations may be required to address the issues that remain outstanding. ?? 2000 Academic Press.

  14. [Fluorescence polarization immunoassay of ractopamine].

    Science.gov (United States)

    Zvereva, E A; Shpakova, N A; Zherdev, A V; Kiu, L; Xu, C; Eremin, S A; Dzantiev, B B

    2016-01-01

    A technique was developed for fluorescence polarization immunoassay (FPIA) of ractopamine, a toxic low molecular weight nonsteroidal growth regulator belonging to the most controlled contaminants of food products of animal origin. The assay is based on the competition between a sample containing ractopamine and ractopamine–fluorophore conjugate for binding to antibodies. The competition is monitored via changes in the degree of fluorescence polarization for plane-polarized excitation light, which differs for the free and antibody-bound forms of the conjugate. The optimal assay conditions were established, ensuring a high accuracy and minimal detection limit. The developed assay demonstrated a detection limit of 1 ng/mL and a range of detectable concentrations of 2.3–50 ng/mL, which met the requirements of sanitary control. The duration of the analysis was 10 min. The possible application of the developed FPIA was demonstrated with testing of turkey meat. The speed and simplicity of the proposed assay define its efficiency as a screening tool for safety of foods.

  15. Polar Heat Flow on Io

    Science.gov (United States)

    Veeder, G. J.; Matson, D. L.; Johnson, T. V.; Davies, A. G.; Blaney, D. L.

    2003-01-01

    Recently, Galileo spacecraft data have revealed Io's polar regions to be much warmer than previously expected. This unexpected development came from Photo-Polarimeter Radiometer (PPR) data which show that the minimum night temperatures are in the range of 90-95 K virtually everywhere on Io. The minimum night temperatures show no dependence upon latitude and, when away from the sunset terminator, they show no dependence upon time of night. This is indeed bizarre behavior for surface units which generally had been assumed to be passive with respect to Io's pervasive volcanism. Night temperatures of 90-95 K at high, polar latitudes are particularly hard to explain. Even assuming infinite thermal inertia, at these latitudes there is insufficient sunlight to support these warm night temperatures. Thus, through the process of elimination of other possibilities, we come to the conclusion that these surfaces are volcanically heated. Taking previously passive units and turning them into new sources of heat flow is a radical departure from previous thermophysical model paradigms. However, the geological interpretation is straight forward. We are simply seeing the effect of old, cool lava flows which cover most of the surface of Io but yet have some heat to radiate. Under these new constraints, we have taken on the challenge of formulating a physical model which quantitatively reproduces all of the observations of Io's thermal emission. In the following we introduce a new parametric model which suffices to identify a previously unrecognized polar component of Io's heat flow.

  16. Anti-Lambda Polarization in High Energy pp Collisions withPolarized Beams

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Qing-hua; Liang, Zuo-tang; Sichtermann, Ernst

    2005-11-06

    We study the polarization of the anti-Lambda particle in polarized high energy pp collisions at large transverse momenta. The anti-Lambda polarization is found to be sensitive to the polarization of the anti-strange sea of the nucleon. We make predictions using different parameterizations of the polarized quark distribution functions. The results show that the measurement of longitudinal anti-Lambda polarization can distinguish different parameterizations, and that similar measurements in the transversely polarized case can give some insights into the transversity distribution of the anti-strange sea of nucleon.

  17. Polarization-beam-splitter-less integrated dual-polarization coherent receiver.

    Science.gov (United States)

    Alonso-Ramos, C; Reyes-Iglesias, P J; Ortega-Moñux, A; Pérez-Galacho, D; Halir, R; Molina-Fernández, I

    2014-08-01

    Conventional dual-polarization coherent receivers require polarization beam splitters for either the signal or the local oscillator path. This severely hinders monolithic integration, since integrated polarization splitting devices often exhibit stringent fabrication tolerances. Here we propose a dual-polarization monolithically integrated coherent receiver architecture that completely avoids the use of polarization splitting elements. Polarization management is instead achieved by adequately engineering the birefringence of the interconnecting waveguides. The resultant receiver is highly tolerant to fabrication deviations and thus offers a completely new route for monolithic integration of dual-polarization receivers without any type of active tuning.

  18. Canadian Preparations for the International Polar Year 2007-2008

    Science.gov (United States)

    Hik, D. S.; Edwards, K. E.

    2006-12-01

    The launch of the International Polar Year on March 1, 2007 will not only mark the beginning of data collection of innovative scientific programs but it will also unleash a series of innovative education and outreach opportunities to increase public awareness of the polar regions and their global impact. IPY education and outreach programs intend to enhance new methods of communication amongst international scientific partners and organizations; inspire the growth and engagement of the next generation of polar researchers; demystify scientific outcomes of IPY into relevant everyday impacts for the public; and express the wonder and significance of the polar regions through medium of art, exhibits, and writing. Canadian researchers, artists, educators and youth are providing significant leadership in the development of such IPY programming and are involved in almost half of the IPO endorsed EOC proposals. Recognizing that Canada has a critical role to play in IPY as host, leader and participant, preparations in Canada have been extensive. A network of national, territorial, and regional organizing bodies has been established to coordinate the development of the national IPY programs; to support the financial and logistical planning; as well as to facilitate the advancement of international partnerships. The success of the Canadian IPY program, measured as either capacity building, strength of partnerships, or efficiency of logistics and operations, will depend upon having committed partners who are specifically part of the Canadian IPY effort. As the Canadian IPY education and outreach program evolves it is being built firmly on partnerships with existing scientific and education organizations in Canada such as youth organizations, national media corporations, and polar science based programs. By building on existing national strengths we are able to capture the existing energy and activity from IPY 2007-2008 to create a longer term sustainable polar education

  19. Hybrid Streamers for Polar Seismic

    Science.gov (United States)

    Gifford, C. M.; Agah, A.; Tsoflias, G. P.

    2006-12-01

    We propose a new hybrid streamer seismic approach for polar regions that incorporates insertion of spiked geophones, the land streamer method of transportation, and mobile robotics. Current land streamers do not plant the geophone spike at each node location on the streamer(s) nor use robotic control. This approach combines the two methods, and is therefore termed "Hybrid Streamers". Land seismic 3D surveying is costly and time consuming due to manual handling of geophones and cables. Multiple streamers make this process simpler by allowing efficient deployment of large numbers of geophones. Hybrid streamers go further to robotically insert the geophone spike at each node location to achieve higher frequency and better resolution seismic images. For deployment and retrieval, the geophone spikes are drilled into the ground, or inserted using heat. This can be accomplished by modifying the geophone spike to be similar to a threaded screw or similar to a soldering iron for polar environments. Heat could help melt the ice during deployment, which would refreeze around the geophone for firm coupling. Heat could also be used to make polar geophone retrieval easier. By ensuring that the towing robots are robust and effective, the problem of single point of failure can be less of an issue. Polar rovers have proven useful in harsh environments, and could be utilized in polar seismic applications. Towing geophone nodes in a tethered fashion not only provides all nodes with power to operate the onboard equipment, but also gives them a medium to transfer data to the towing rover. Hybrid streamers could be used in several ways. One or more hybrid streamers could be tethered and towed by a single robot. Several robots could be used to form a single grid, working in conjunction to image larger areas in three dimensions. Such an approach could speed up entire missions and make efficient use of seismic source ignitions. The reduction of human involvement by use of mobile robots

  20. Baryon spectroscopy with polarization observables from CLAS

    Energy Technology Data Exchange (ETDEWEB)

    Strauch, Steffen [Univ. of South Carolina, Columbia, SC (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

    2016-11-01

    The spectrum of nucleon excitations is dominated by broad and overlapping resonances. Polarization observables in photoproduction reactions are key in the study of these excitations. They give indispensable constraints to partial-wave analyses and help clarify the spectrum. A series of polarized photoproduction experiments have been performed at the Thomas Jefferson National Accelerator Facility with the CEBAF Large Acceptance Spectrometer (CLAS). These measurements include data with linearly and circularly polarized tagged-photon beams, longitudinally and transversely polarized proton and deuterium targets, and recoil polarizations through the observation of the weak decay of hyperons. An overview of these studies and recent results will be given.

  1. Nonlinear Gyrokinetic Theory With Polarization Drift

    International Nuclear Information System (INIS)

    Wang, L.; Hahm, T.S.

    2010-01-01

    A set of the electrostatic toroidal gyrokinetic Vlasov equation and the Poisson equation, which explicitly includes the polarization drift, is derived systematically by using Lie-transform method. The polarization drift is introduced in the gyrocenter equations of motion, and the corresponding polarization density is derived. Contrary to the wide-spread expectation, the inclusion of the polarization drift in the gyrocenter equations of motion does not affect the expression for the polarization density significantly. This is due to modification of the gyrocenter phase-space volume caused by the electrostatic potential [T. S. Hahm, Phys. Plasmas 3, 4658 (1996)].

  2. HAWC+/SOFIA Instrumental Polarization Calibration

    Science.gov (United States)

    Michail, Joseph M.; Chuss, David; Dowell, Charles D.; Santos, Fabio; Siah, Javad; Vaillancourt, John; HAWC+ Instrument Team

    2018-01-01

    HAWC+ is a new far-infrared polarimeter for the NASA/DLR SOFIA (Stratospheric Observatory for Infrared Astronomy) telescope. HAWC+ has the capability to measure the polarization of astronomical sources with unprecedented sensitivity and angular resolution in four bands from 50-250 microns. Using data obtained during commissioning flights, we implemented a calibration strategy that separates the astronomical polarization signal from the induced instrumental polarization. The result of this analysis is a map of the instrumental polarization as a function of position in the instrument's focal plane in each band. The results show consistency between bands, as well as with other methods used to determine preliminary instrumental polarization values.

  3. Climate Change, Polar Bears and their management

    OpenAIRE

    Derenchenko, Liza

    2010-01-01

    This is a literature study of polar bears in the context of climate change: what kind of creatures are polar bears, what are the main interpretations of current climate change, how might the polar bear adapt to these changes (feeding strategies) and how are the bears being managed (hunting)? These are relevant questions , since climate change is on the agenda, and polar bears being the apex predators of the Arctic are a key representation of the wildlife there. The third element of polar bear...

  4. Optically pumped polarized H- ion source

    International Nuclear Information System (INIS)

    Anderson, L.W.

    1986-01-01

    The current status and future prospects for the optically pumped polarized H - ion source are discussed. At the present time H - ion currents of 60 μA and with a polarization of 65% have been produced. The ion current and polarization can be increased significantly if the optically pumped Na charge exchange target density and polarization can be increased. Studies of wall surfaces that permit many bounces before depolarizing the Na electron spin and studies of radiation trapping in optically pumped Na indicate that the Na target density and polarization can be increased substantially. 27 refs., 6 figs., 2 tabs

  5. The optics of secondary polarized proton beams

    International Nuclear Information System (INIS)

    Carey, D.C.

    1990-05-01

    Polarized protons can be produced by the parity-violating decay of either lambda or sigma hyperons. A secondary bema of polarized protons can then be produced without the difficult procedure of accelerating polarized protons. The preservation of the polarization while the protons are being transmitted to a final focus places stringent limitations on the optics of the beam line. The equations of motion of a polarized particle in a magnetic field have been solved to first order for quadrupole and dipole magnets. The lowest order terms indicate that the polarization vector will be restored to its original direction upon passage through a magnetic system if the momentum vector is unaltered. Higher-order terms may be derived by an expansion in commutators of the rotation matrix and its longitudinal derivative. The higher-order polarization rotation terms then arise from the non-commutivity of the rotation matrices by large angles in three-dimensional space. 5 refs., 3 figs

  6. On the large COMPASS polarized deuteron target

    CERN Document Server

    Finger, M; Baum, G; Doshita, N; Finger, M Jr; Gautheron, F; Goertz, St; Hasegawa, T; Heckmann, J; Hess, Ch; Horikawa, N; Ishimoto, S; Iwata, T; Kisselev, Y; Koivuniemi, J; Kondo, K; Le Goff, J-M; Magnon, A; Marchand, C; Matsuda, T; Meyer, W; Reicherz, G; Srnka, A

    2006-01-01

    The spin structure of the nucleons is investigated in deep inelastic scattering of a polarized muon beam and a polarized nucleon target in the COMPASS experiment at CERN since 2001. To achieve high luminosities a large solid polarized target is used. The COMPASS polarized target consists of a high cooling power $^{3}$He/$^{4}$He dilution refrigerator capable to maintain working temperature of the target material at about 50mK, a superconducting solenoid and dipole magnet system for longitudinal and transversal magnetic field on the target material, respectively, target cells containing polarizable material, microwave cavities and high power microwave radiation systems for dynamic nuclear polarization and the nuclear magnetic resonance system for nuclear spin polarization measurements. During 2001–2004 experiments superconducting magnet system with opening angle $\\pm$69 mrad, polarized target holder with two target cells and corresponding microwave and NMR systems have been used. For the data taking from 200...

  7. Environmental challenges and opportunities of the evolving North American electricity market : Modeling techniques and estimating environmental outcomes[Secretariat report to Council under article 13 of the North American agreement on environmental cooperation

    Energy Technology Data Exchange (ETDEWEB)

    Patterson, Z. [Commission for Environmental Cooperation of North America, Montreal, PQ (Canada)

    2002-06-01

    Background information and results of the different models publicly available used for the evaluation of environmental effects of electricity market restructuring in the various jurisdictions in North America were included in this working paper. It comprised the description of eleven models and twelve modeling exercises. The information on each model varied greatly, as it is proprietary. The models described were: (1) the Energy Information Administration's (EIA) National Energy Modeling System (NEMS), (2) the Department of Energy's Policy Office Electricity Modeling System (POEMS), (3) the Integrated Planning Model (IPM) utilized by the United States Environmental Protection Agency (US EPA), (4) Resources for the Future's (RFF) Haiku model, (5) the Canadian Energy Research Institute's Energy 2020 Model, (6) the Federal Energy Regulatory Commission's (FERC) use of ICF's Coal and Electric Utilities Model, (7) the Center for Clean Air Policy's use of General Electric's Market Assessment and Portfolio Strategies (GE MAPS) model, (8) the Center for Clean Air Policy's use of GE MAPS in combination with New Energy Associates' Proscreen II, (9) the Commission for Environmental Cooperation use of the Front of Envelope Model, (10) Ontario Power Generation's use of the Utility Fuel Economics Model and National Power Model, and (11) New York State Department of Public Service's (NYDPS) Final Generic Environmental Impact Statement using New Energy Associates' PROMOD. Also included in this working paper was a comparison of the results of models and modeling exercises on which the estimation of the environmental effects of electricity market restructuring in the United States was based. 18 refs., 5 tabs.

  8. Environmental impact on the polar regions

    International Nuclear Information System (INIS)

    Jaffe, D.A.; Leighton, E.; Tumeo, M.A.

    1994-01-01

    The remote and frigid polar regions are no longer isolated from the activities, pollutants, and controversies that bedevil their more temperate neighbors, say three researchers at the University of Alaska in Fairbanks. For example, Daniel A. Jaffe, Elizabeth Leighton, and Mark A. Tumeo point to traces of DDT, PCBs, and heavy metals that routinely turn up in arctic marine mammals and to the ozone hole over the Antarctic. While similar in environmental makeup, the arctic and Antarctic are poles apart in their political structure and, thus, in their environmental exposure, the researchers note. The Antarctic is managed under a long-standing international treaty, while the arctic is sovereign territory to eight separate nations. The international treaty sets aside the Antarctic for peaceful scientific research within strict environmental boundaries. It bans both military activity and minerals extraction-the two activities that have caused the most damage in the arctic. The main threats to Antarctica's environment come from the intrusion of major scientific research operations and the growing tourism industry. On the other hand, the arctic suffered from the massive Cold War military buildup by both the United States and the former Soviet Union. The environmental residue from that buildup is only now being revealed, the authors say. Major oil and gas drilling and coal and metal-ore mining also have taken a huge environmental toll, they add

  9. Validation of External Corrosion Growth-Rate Using Polarization Resistance and Soil Properties

    Science.gov (United States)

    2010-08-01

    The research project evaluated the use of the Linear Polarization Resistance (LPR) and the Electric Resistance (ER) technologies in estimating the external corrosion growth rates of buried steel pipelines. This was achieved by performing laboratory a...

  10. [Analysis of influencing factors of snow hyperspectral polarized reflections].

    Science.gov (United States)

    Sun, Zhong-Qiu; Zhao, Yun-Sheng; Yan, Guo-Qian; Ning, Yan-Ling; Zhong, Gui-Xin

    2010-02-01

    Due to the need of snow monitoring and the impact of the global change on the snow, on the basis of the traditional research on snow, starting from the perspective of multi-angle polarized reflectance, we analyzed the influencing factors of snow from the incidence zenith angles, the detection zenith angles, the detection azimuth angles, polarized angles, the density of snow, the degree of pollution, and the background of the undersurface. It was found that these factors affected the spectral reflectance values of the snow, and the effect of some factors on the polarization hyperspectral reflectance observation is more evident than in the vertical observation. Among these influencing factors, the pollution of snow leads to an obvious change in the snow reflectance spectrum curve, while other factors have little effect on the shape of the snow reflectance spectrum curve and mainly impact the reflection ratio of the snow. Snow reflectance polarization information has not only important theoretical significance, but also wide application prospect, and provides new ideas and methods for the quantitative research on snow using the remote sensing technology.

  11. Polar patterns of driven filaments.

    Science.gov (United States)

    Schaller, Volker; Weber, Christoph; Semmrich, Christine; Frey, Erwin; Bausch, Andreas R

    2010-09-02

    The emergence of collective motion exhibited by systems ranging from flocks of animals to self-propelled microorganisms to the cytoskeleton is a ubiquitous and fascinating self-organization phenomenon. Similarities between these systems, such as the inherent polarity of the constituents, a density-dependent transition to ordered phases or the existence of very large density fluctuations, suggest universal principles underlying pattern formation. This idea is followed by theoretical models at all levels of description: micro- or mesoscopic models directly map local forces and interactions using only a few, preferably simple, interaction rules, and more macroscopic approaches in the hydrodynamic limit rely on the systems' generic symmetries. All these models characteristically have a broad parameter space with a manifold of possible patterns, most of which have not yet been experimentally verified. The complexity of interactions and the limited parameter control of existing experimental systems are major obstacles to our understanding of the underlying ordering principles. Here we demonstrate the emergence of collective motion in a high-density motility assay that consists of highly concentrated actin filaments propelled by immobilized molecular motors in a planar geometry. Above a critical density, the filaments self-organize to form coherently moving structures with persistent density modulations, such as clusters, swirls and interconnected bands. These polar nematic structures are long lived and can span length scales orders of magnitudes larger than their constituents. Our experimental approach, which offers control of all relevant system parameters, complemented by agent-based simulations, allows backtracking of the assembly and disassembly pathways to the underlying local interactions. We identify weak and local alignment interactions to be essential for the observed formation of patterns and their dynamics. The presented minimal polar-pattern-forming system

  12. Polarized particles for accelerator physicists

    International Nuclear Information System (INIS)

    Bell, J.S.

    1975-01-01

    These lectures deal in an elementary way with the concept of particle polarization and its behaviour in the presence of electromagnetic fields. The first part introduces the basic notions and essential equations in a purely phenomenological way, beginning with spin-1/2 particles and then extending the discussion to particles of arbitrary spin. Among the topics discussed are magnetic precession and the muon g-2 experiment. The second part begins with an introduction to non-relativistic wave mechanics, and then develops the quantum-theoretic interpretation of the phenomenological equations for particles with spin 1/2, 1, and higher. (Author)

  13. PSI: Very slow polarized muons

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    At the 'pion factory' of the Swiss Paul Scherrer Institute, a collaboration of PSI, Heidelberg and Zurich (ETH) has recently produced intense beams of positive muons which have kinetic energies as low as 10 eV and with complete polarization (spin orientation). The new results were achieved at a surface muon channel, transporting positive muons from the decay of positive pions stopped at the surface of a pion production target. Surface muons with 4 MeV kinetic energy were transported by a conventional secondary beam channel and partially stopped in a moderator consisting of a layer of solidified noble gas deposited on a cold metallic substrate

  14. Higher education, wages, and polarization

    OpenAIRE

    Valletta, Robert G.

    2015-01-01

    The earnings gap between people with a college degree and those with no education beyond high school has been growing since the late 1970s. Since 2000, however, the gap has grown more for those who have earned a post-graduate degree as well. The divergence between workers with college degrees and those with graduate degrees may be one manifestation of rising labor market polarization, which benefits those earning the highest and the lowest wages relatively more than those in the middle of the...

  15. Water Ice Albedo Variations on the Martian Northern Polar Cap

    Science.gov (United States)

    Hale, A. S.; Bass, D. S.; Tamppari, L. K.

    2003-01-01

    The Viking Orbiters determined that the surface of Mars northern residual cap is water ice. Many researchers have related observed atmospheric water vapor abundances to seasonal exchange between reservoirs such as the polar caps, but the extent to which the exchange between the surface and the atmosphere remains uncertain. Early studies of the ice coverage and albedo of the northern residual Martian polar cap using Mariner 9 and Viking images reported that there were substantial internannual differences in ice deposition on the polar cap, a result which suggested a highly variable Martian climate. However, some of the data used in these studies were obtained at differing values of heliocentric solar longitude (L(sub s)). Reevaluation of this dataset indicated that the residual cap undergoes seasonal brightening throughout the summer, and indicated that this process repeats from year to year. In this study we continue to compare Mariner 9 and Viking Orbiter imaging observations and thermal data of the north residual polar cap to data acquired with Mars Global Surveyor s Mars Orbiter Camera (MOC) instrument. In the current study, our goal is to examine all released data from MGS MOC in the northern summer season, along with applicable TES data in order to better understand the albedo variations in the northern summer and their implications on water transport. To date, work has focused primarily on the MOC dataset. In 1999, data acquisition of the northern polar regions began at L(sub s) = 107, although there was little north polar data acquired from L(sub s)= 107 to L(sub s) = 109. We examined a total of 409 images from L(sub s) = 107 to L(sub s)=148. We have also examined data from 2000 from L(sub s)= 93 to L(sub s)= 110; additional progress is ongoing. Here we present a progress report of our observations, and continue to determine their implications for the Martian water cycle.

  16. Polar Science Weekend: A University / Science Center Collaboration

    Science.gov (United States)

    Stern, H. L.; Moritz, R. E.; Lettvin, E.; Schatz, D.; Russell, L.

    2008-12-01

    Polar Science Weekend (PSW) is a four-day event featuring hands-on activities, live demonstrations, and a variety of exhibits about the polar regions and current polar research, presented by scientists from the University of Washington's Polar Science Center, and held at Seattle's Pacific Science Center. PSW was conceived and organized jointly by the Polar Science Center and Pacific Science Center, which is Washington State's most well-attended museum. The first PSW in March 2006 drew over 5000 visitors, and subsequent PSWs in 2007 and 2008 have both surpassed that figure. The success of this university / science center partnership has made PSW an annual event, and has served as a model for Pacific Science Center's Portal to the Public program, in which partnerships with other scientific institutions have been built. Researchers at the Polar Science Center (PSC) study the physical processes controlling high-latitude oceans, atmosphere, sea ice, and ice sheets, and are involved in numerous IPY projects. PSC scientists also engage in many outreach efforts such as classroom visits and public lectures, but PSW stands out as the highlight of the year. The partnership with Pacific Science Center brings access to facilities, publicity, and a large audience that would not otherwise be readily available to PSC. Pacific Science Center, constructed for the 1962 World's Fair in Seattle, serves more than one million visitors per year. Pacific Science Center's mission is to inspire a lifelong interest in science, math and technology by engaging diverse communities through interactive and innovative exhibits and programs. PSW helps to advance this mission by bringing students, teachers, and families face-to-face with scientists who work in some of the most remote and challenging places on earth, to learn first-hand about polar research in a fun and informal setting. This is made possible only by the partnership with PSC. In this talk we will present descriptions and photos of PSW

  17. Tensor Target Polarization at TRIUMF

    Energy Technology Data Exchange (ETDEWEB)

    Smith, G

    2014-10-27

    The first measurements of tensor observables in $\\pi \\vec{d}$ scattering experiments were performed in the mid-80's at TRIUMF, and later at SIN/PSI. The full suite of tensor observables accessible in $\\pi \\vec{d}$ elastic scattering were measured: $T_{20}$, $T_{21}$, and $T_{22}$. The vector analyzing power $iT_{11}$ was also measured. These results led to a better understanding of the three-body theory used to describe this reaction. %Some measurements were also made in the absorption and breakup channels. A direct measurement of the target tensor polarization was also made independent of the usual NMR techniques by exploiting the (nearly) model-independent result for the tensor analyzing power at 90$^\\circ _{cm}$ in the $\\pi \\vec{d} \\rightarrow 2p$ reaction. This method was also used to check efforts to enhance the tensor polarization by RF burning of the NMR spectrum. A brief description of the methods developed to measure and analyze these experiments is provided.

  18. Optical polarization: background and camouflage

    Science.gov (United States)

    Škerlind, Christina; Hallberg, Tomas; Eriksson, Johan; Kariis, Hans; Bergström, David

    2017-10-01

    Polarimetric imaging sensors in the electro-optical region, already military and commercially available in both the visual and infrared, show enhanced capabilities for advanced target detection and recognition. The capabilities arise due to the ability to discriminate between man-made and natural background surfaces using the polarization information of light. In the development of materials for signature management in the visible and infrared wavelength regions, different criteria need to be met to fulfil the requirements for a good camouflage against modern sensors. In conventional camouflage design, the aimed design of the surface properties of an object is to spectrally match or adapt it to a background and thereby minimizing the contrast given by a specific threat sensor. Examples will be shown from measurements of some relevant materials and how they in different ways affect the polarimetric signature. Dimensioning properties relevant in an optical camouflage from a polarimetric perspective, such as degree of polarization, the viewing or incident angle, and amount of diffuse reflection, mainly in the infrared region, will be discussed.

  19. Polarized View of Supercooled Liquid Water Clouds

    Science.gov (United States)

    Alexandrov, Mikhail D.; Cairns, Brian; Van Diedenhoven, Bastiaan; Ackerman, Andrew S.; Wasilewski, Andrzej P.; McGill, Matthew J.; Yorks, John E.; Hlavka, Dennis L.; Platnick, Steven E.; Arnold, G. Thomas

    2016-01-01

    Supercooled liquid water (SLW) clouds, where liquid droplets exist at temperatures below 0 C present a well known aviation hazard through aircraft icing, in which SLW accretes on the airframe. SLW clouds are common over the Southern Ocean, and climate-induced changes in their occurrence is thought to constitute a strong cloud feedback on global climate. The two recent NASA field campaigns POlarimeter Definition EXperiment (PODEX, based in Palmdale, California, January-February 2013) and Studies of Emissions and Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys (SEAC4RS, based in Houston, Texas in August- September 2013) provided a unique opportunity to observe SLW clouds from the high-altitude airborne platform of NASA's ER-2 aircraft. We present an analysis of measurements made by the Research Scanning Polarimeter (RSP) during these experiments accompanied by correlative retrievals from other sensors. The RSP measures both polarized and total reflectance in 9 spectral channels with wavelengths ranging from 410 to 2250 nm. It is a scanning sensor taking samples at 0.8deg intervals within 60deg from nadir in both forward and backward directions. This unique angular resolution allows for characterization of liquid water droplet size using the rainbow structure observed in the polarized reflectances in the scattering angle range between 135deg and 165deg. Simple parametric fitting algorithms applied to the polarized reflectance provide retrievals of the droplet effective radius and variance assuming a prescribed size distribution shape (gamma distribution). In addition to this, we use a non-parametric method, Rainbow Fourier Transform (RFT),which allows retrieval of the droplet size distribution without assuming a size distribution shape. We present an overview of the RSP campaign datasets available from the NASA GISS website, as well as two detailed examples of the retrievals. In these case studies we focus on cloud fields with spatial features

  20. Optical detection dental disease using polarized light

    Science.gov (United States)

    Everett, Matthew J.; Colston, Jr., Billy W.; Sathyam, Ujwal S.; Da Silva, Luiz B.; Fried, Daniel

    2003-01-01

    A polarization sensitive optical imaging system is used to detect changes in polarization in dental tissues to aid the diagnosis of dental disease such as caries. The degree of depolarization is measured by illuminating the dental tissue with polarized light and measuring the polarization state of the backscattered light. The polarization state of this reflected light is analyzed using optical polarimetric imaging techniques. A hand-held fiber optic dental probe is used in vivo to direct the incident beam to the dental tissue and collect the reflected light. To provide depth-resolved characterization of the dental tissue, the polarization diagnostics may be incorporated into optical coherence domain reflectometry and optical coherence tomography (OCDR/OCT) systems, which enables identification of subsurface depolarization sites associated with demineralization of enamel or bone.

  1. Polarization Observations of the Fermi blazars

    Science.gov (United States)

    Rani, Bindu; S. Jorstad, A. P. Marscher (BU, USA), K. Sokolovsky (IAASARS, Greece), I. Agudo (CSIC, Spain)

    2018-01-01

    Ever since the revolutionary discovery by the Fermi mission that active galactic nuclei (AGN) produce copious amounts of high-energy emission, its origin has remained elusive. Using high-frequency radio interferometry (VLBI) polarization imaging, we could probe the magnetic field topology of the compact high-energy emission regions in blazars. A case study for blazar 3C 279 reveals presence of multiple gamma-ray emission regions. The observed anti-correlation between gamma-ray flux and percentage polarization at optical bands challenges the current high-energy emission models. In addition to the turbulent component responsible for gamma-ray flares, our analysis suggests the presence of a steady polarized component having with its polarization direction aligned along the jet axis. The steady polarized component could possibly be the toroidal component of the helical magnetic field. To better understand the acceleration processes in jets, high-energy polarization missions are of great importance.

  2. A polarizing neutron periscope for neutron imaging

    International Nuclear Information System (INIS)

    Schulz, Michael; Boeni, Peter; Calzada, Elbio; Muehlbauer, Martin; Neubauer, Andreas; Schillinger, Burkhard

    2009-01-01

    Optical neutron polarizers like guides or benders destroy the collimation of a neutron beam due to multiple reflections or scattering. This makes them unsuitable for their use in polarized neutron radiography, because the beam collimation is essential to obtain high spatial resolution. We have developed a neutron polarizer based on the principle of an optical periscope with a zigzag double reflection on two parallel high-m supermirror polarizers. If the supermirrors are perfectly parallel and flat, the beam collimation is left unchanged by such a device. A first proof of concept version of this type of polarizer was built and tested. We expect to achieve a beam polarization of up to 99% with an improved version yet to be built.

  3. A polarizing neutron periscope for neutron imaging

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, Michael [FRM II, Lichtenbergstr. 1, 85748 Garching (Germany); Technische Universitaet Muenchen, Physik Department E21, James Franck Strasse, 85748 Garching (Germany)], E-mail: Michael.Schulz@frm2.tum.de; Boeni, Peter [Technische Universitaet Muenchen, Physik Department E21, James Franck Strasse, 85748 Garching (Germany); Calzada, Elbio; Muehlbauer, Martin [FRM II, Lichtenbergstr. 1, 85748 Garching (Germany); Technische Universitaet Muenchen, Physik Department E21, James Franck Strasse, 85748 Garching (Germany); Neubauer, Andreas [Technische Universitaet Muenchen, Physik Department E21, James Franck Strasse, 85748 Garching (Germany); Schillinger, Burkhard [FRM II, Lichtenbergstr. 1, 85748 Garching (Germany); Technische Universitaet Muenchen, Physik Department E21, James Franck Strasse, 85748 Garching (Germany)

    2009-06-21

    Optical neutron polarizers like guides or benders destroy the collimation of a neutron beam due to multiple reflections or scattering. This makes them unsuitable for their use in polarized neutron radiography, because the beam collimation is essential to obtain high spatial resolution. We have developed a neutron polarizer based on the principle of an optical periscope with a zigzag double reflection on two parallel high-m supermirror polarizers. If the supermirrors are perfectly parallel and flat, the beam collimation is left unchanged by such a device. A first proof of concept version of this type of polarizer was built and tested. We expect to achieve a beam polarization of up to 99% with an improved version yet to be built.

  4. An optically pumped polarized lithium ion source

    International Nuclear Information System (INIS)

    Myers, E.G.; Mendez, A.J.; Schmidt, B.G.; Kemper, K.W.

    1991-01-01

    A laser-optically-pumped polarized lithium ion source is being developed to provide beams of nuclear polarized 6,7 Li - for injection into the FSU tandem Van de Graaff-linac. Electro-optically modulated, circularly polarized light optically pumps a lithium atomic beam into a single magnetic substate, M 1 =1, M J =1/2. No inhomogeneous magnetic field (sextupole or quadrupole) is needed. Adiabatic rf transitions enable the polarization to be changed by transferring the population into different magnetic substates. Using a second electro-optic to modulate a second beam from the same laser, and Zeeman tuning, the polarization of the atomic beam is obtained by laser induced fluorescence. The polarized atomic beam is ionized to Li + and then charge exchanged to Li - . (orig.)

  5. Accelerating and storing polarized hadron beams

    International Nuclear Information System (INIS)

    Teng, L.C.

    1990-10-01

    Polarization hadron experiments at high energies continue to generate surprises. Many questions remain unanswered or unanswerable within the frame work of QCD. These include such basic questions as to why at high energies the polarization analyzing power in pp elastic scattering remains high, why hyperons are produced with high polarizations etc. It is, therefore, interesting to investigate the possibilities of accelerating and storing polarized beams in high energy colliders. On the technical side the recent understanding and confirmation of the actions of partial and multiple Siberian snakes made it possible to contemplate accelerating and storing polarized hadron beams to multi-TeV energies. In this paper, we will examine the equipment, the operation and the procedure required to obtain colliding beams of polarized protons at TeV energies

  6. Oocytes Polar Body Detection for Automatic Enucleation

    Directory of Open Access Journals (Sweden)

    Di Chen

    2016-02-01

    Full Text Available Enucleation is a crucial step in cloning. In order to achieve automatic blind enucleation, we should detect the polar body of the oocyte automatically. The conventional polar body detection approaches have low success rate or low efficiency. We propose a polar body detection method based on machine learning in this paper. On one hand, the improved Histogram of Oriented Gradient (HOG algorithm is employed to extract features of polar body images, which will increase success rate. On the other hand, a position prediction method is put forward to narrow the search range of polar body, which will improve efficiency. Experiment results show that the success rate is 96% for various types of polar bodies. Furthermore, the method is applied to an enucleation experiment and improves the degree of automatic enucleation.

  7. Physical processes in spin polarized plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Kulsrud, R.M.; Valeo, E.J.; Cowley, S.

    1984-05-01

    If the plasma in a nuclear fusion reactor is polarized, the nuclear reactions are modified in such a way as to enhance the reactor performance. We calculate in detail the modification of these nuclear reactions by different modes of polarization of the nuclear fuel. We also consider in detail the various physical processes that can lead to depolarization and show that they are by and large slow enough that a high degree of polarization can be maintained.

  8. The origin of radio pulsar polarization

    Science.gov (United States)

    Dyks, J.

    2017-12-01

    Polarization of radio pulsar profiles involves a number of poorly understood, intriguing phenomena, such as the existence of comparable amounts of orthogonal polarization modes (OPMs), strong distortions of polarization angle (PA) curves into shapes inconsistent with the rotating vector model (RVM), and the strong circular polarization V which can be maximum (instead of zero) at the OPM jumps. It is shown that the comparable OPMs and large V result from a coherent addition of phase-delayed waves in natural propagation modes, which are produced by a linearly polarized emitted signal. The coherent mode summation implies opposite polarization properties to those known from the incoherent case, in particular, the OPM jumps occur at peaks of V, whereas V changes sign at a maximum linear polarization fraction L/I. These features are indispensable to interpret various observed polarization effects. It is shown that statistical properties of emission and propagation can be efficiently parametrized in a simple model of coherent mode addition, which is successfully applied to complex polarization phenomena, such as the stepwise PA curve of PSR B1913+16 and the strong PA distortions within core components of pulsars B1933+16 and B1237+25. The inclusion of coherent mode addition opens the possibility for a number of new polarization effects, such as inversion of relative modal strength, twin minima in L/I coincident with peaks in V, 45° PA jumps in weakly polarized emission, and loop-shaped core PA distortions. The empirical treatment of the coherency of mode addition makes it possible to advance the understanding of pulsar polarization beyond the RVM model.

  9. Polarization Effects in Attosecond Photoelectron Spectroscopy

    DEFF Research Database (Denmark)

    Baggesen, Jan Conrad; Madsen, Lars Bojer

    2010-01-01

    following the field instead. We show that polarization effects may lead to an apparent temporal shift that needs to be properly accounted for in the analysis. The effect may be isolated and studied by angle-resolved photoelectron spectroscopy from oriented polar molecules. We also show that polarization...... effects will lead to an apparent temporal shift of 50 as between photoelectrons from a 2p and 1s state in atomic hydrogen....

  10. Polarized deuteron beam at the Dubna synchrophasotron

    International Nuclear Information System (INIS)

    Ershov, V.P.; Fimushkin, V.V.; Gai, G.I.

    1990-01-01

    The experimental equipment and setup used to accelerate a polarized deuteron beam at the Dubna synchrophasotron are briefly described. Basic characteristics of the cryogenic source of polarized deuterons POLARIS are presented. The results of measurements of the intensity of the accelerated beam, vector and tensor polarization at the output of the linac LU-20, inside the synchrophasotron ring and in the extracted beam are given. 16 refs.; 9 figs.; 3 tabs

  11. Imaging differential polarization microscope with electronic readout

    International Nuclear Information System (INIS)

    Mickols, W.; Tinoco, I.; Katz, J.E.; Maestre, M.F.; Bustamante, C.

    1985-01-01

    A differential polarization microscope forms two images: one of the transmitted intensity and the other due to the change in intensity between images formed when different polarizations of light are used. The interpretation of these images for linear dichroism and circular dichroism are described. The design constraints on the data acquisition systems and the polarization modulation are described. The advantage of imaging several biological systems which contain optically anisotropic structures are described

  12. The polarization and beaming effect for GRBs

    OpenAIRE

    Cheng, K. S.; Fan, J. H.; Dai, Z. G.

    1999-01-01

    Both observations and theoretical models suggest that the emissions in gamma-ray bursts (GRBs) and the afterglows are beamed. We argue that the recent polarization measured in the afterglows gives further evidence of beaming in GRBs. In this approach, we adopted the polarization-magnitude relation of BL Lacertae objects to 4 GRBs with available polarization measurements and found that the data of the 4 GRBs are consistent with the relation of BL Lacertae objects. This result suggests that the...

  13. Studying Magnetohydrodynamic Turbulence with Synchrotron Polarization Dispersion

    OpenAIRE

    Zhang, Jian-Fu; Lazarian, Alex; Lee, Hyeseung; Cho, Jungyeon

    2016-01-01

    We test a new technique of studying magnetohydrodynamic (MHD) turbulence suggested by Lazarian \\& Pogosyan, using synthetic synchrotron polarization observations. This paper focuses on a one-point statistics, which is termed the polarization frequency analysis, that is characterized by the variance of polarized emission as a function of the square of wavelengths along a single line of sight. We adopt a ratio $\\eta$ of the standard deviation of the line-of-sight turbulent magnetic field to the...

  14. Primordial Inflation Polarization Explorer: Status and Plans

    Science.gov (United States)

    Kogut, Alan

    2009-01-01

    The Primordial Inflation Polarization Explorer is a balloon-borne instrument to measure the polarization of the cosmic microwave background in order to detect the characteristic signature of gravity waves created during an inflationary epoch in the early universe. PIPER combines cold /I.G K\\ optics, 5120 bolometric detectors, and rapid polarization modulation using VPM grids to achieve both high sensitivity and excellent control of systematic errors. I will discuss the current status and plans for the PIPER instrument.

  15. Epithelial cell polarity, stem cells and cancer

    DEFF Research Database (Denmark)

    Martin-Belmonte, Fernando; Perez-Moreno, Mirna

    2011-01-01

    After years of extensive scientific discovery much has been learned about the networks that regulate epithelial homeostasis. Loss of expression or functional activity of cell adhesion and cell polarity proteins (including the PAR, crumbs (CRB) and scribble (SCRIB) complexes) is intricately related......, deregulation of adhesion and polarity proteins can cause misoriented cell divisions and increased self-renewal of adult epithelial stem cells. In this Review, we highlight some advances in the understanding of how loss of epithelial cell polarity contributes to tumorigenesis....

  16. Past lessons and future importance of polarization

    International Nuclear Information System (INIS)

    Lipkin, H.J.

    1980-01-01

    Polarization and spin effects have traditionally brought surprises to physicists particularly to those who thought that such effects were unimportant. In hadron physics, large unexplained effects keep turning up and are still unresolved puzzles. A good measurement of the uninteresting beta ray polarization could have discovered parity nonconservation many years before its prediction by Lee and Yang. Nobody knows whether there are further exciting discoveries of this kind waiting for polarization experiments

  17. RHIC polarized proton performance in run-8.

    Energy Technology Data Exchange (ETDEWEB)

    Montag,C.; Abreu, N.; Ahrens, L.; Bai, M.; Barton, D.; et al.

    2008-06-23

    During Run-8, the Relativistic Heavy Ion Collider (RHIC) provided collisions of spin-polarized proton beams at two interaction regions. Helical spin rotators at these two interaction regions were used to control the spin orientation of both beams at the collision points. Physics data were taken with different orientations of the beam polarization. We present recent developments and improvements as well as the luminosity and polarization performance achieved during Run-8.

  18. Documents of the first committee. Note by the Secretariat. Addendum

    International Nuclear Information System (INIS)

    1993-01-01

    The document contains agenda items, concerning in particular the following issues: verification in all its aspects, including the role of the United Nations in the field of verification; amendment of the Treaty Banning Nuclear Weapon Tests in the Atmosphere, in Outer Space and under Water; comprehensive nuclear-test-ban treaty; establishment of a nuclear-weapon-free zone in the region of the Middle East, in South Asia; conclusion of effective international agreements to assure non-nuclear-weapon States against the use or threat of use of nuclear weapons; general and complete disarmament; prohibition of the dumping of radioactive wastes; convention on the Prohibition of the Use of Nuclear Weapons; nuclear-arms freeze; consolidation of the regime established by the Treaty of Tlatelolco; implementation of the declaration on the denuclearization of Africa

  19. List of documents received by the INDC Secretariat

    International Nuclear Information System (INIS)

    1980-06-01

    This list is produced directly from computer printout in two sorts: one ordered by accession number, and the other ordered by document number within each origin series (e.g. listing all INDC(SEC)-documents in one block). Reference to earlier INDSWG and ''interim'' INDC reports received between 1962 and 1967 are listed in report INDC/199 (dated November 1967)

  20. The Commission and the Council Secretariat in the 2000 IGC

    DEFF Research Database (Denmark)

    Beach, Derek

    2006-01-01

    and actual strategies employed by supranational actors in an IGC. Following this, the chapter will first review the preferences of the two supranational actors in the 2000 IGC, showing that they do not always reflect Member State government preferences. Thereafter, the chapter looks......, and with civil servants in both the United Kingdom and Denmark, along with relevant primary and secondary literature. In the conclusion, these results are compared against the relative influence of the two institutions in other IGCs, and with the parallel negotiation of the EU Charter of Fundamental Rights....

  1. Numerical modelling of electrochemical polarization around charged metallic particles

    Science.gov (United States)

    Bücker, Matthias; Undorf, Sabine; Flores Orozco, Adrián; Kemna, Andreas

    2017-04-01

    We extend an existing analytical model and carry out numerical simulations to study the polarization process around charged metallic particles immersed in an electrolyte solution. Electro-migration and diffusion processes in the electrolyte are described by the Poisson-Nernst-Planck system of partial differential equations. To model the surface charge density, we consider a time- and frequency-invariant electric potential at the particle surface, which leads to the build-up of a static electrical double layer (EDL). Upon excitation by an external electric field at low frequencies, we observe the superposition of two polarization processes. On the one hand, the induced dipole moment on the metallic particle leads to the accumulation of opposite charges in the electrolyte. This charge polarization corresponds to the long-known response of uncharged metallic particles. On the other hand, the unequal cation and anion concentrations in the EDL give rise to a salinity gradient between the two opposite sides of the metallic particle. The resulting concentration polarization enhances the magnitude of the overall polarization response. Furthermore, we use our numerical model to study the effect of relevant model parameters such as surface charge density and ionic strength of the electrolyte on the resulting spectra of the effective conductivity of the composite model system. Our results do not only give interesting new insight into the time-harmonic variation of electric potential and ion concentrations around charged metallic particle. They are also able to reduce incongruities between earlier model predictions and geophysical field and laboratory measurements. Our model thereby improves the general understanding of IP signatures of metallic particles and represents the next step towards a quantitative interpretation of IP imaging results. Part of this research is funded by the Austrian Federal Ministry of Science, Research and Economy under the Raw Materials Initiative.

  2. Thermal stability of tunneling spin polarization

    International Nuclear Information System (INIS)

    Kant, C.H.; Kohlhepp, J.T.; Paluskar, P.V.; Swagten, H.J.M.; Jonge, W.J.M. de

    2005-01-01

    We present a study of the thermal stability of tunneling spin polarization in Al/AlOx/ferromagnet junctions based on the spin-polarized tunneling technique, in which the Zeeman-split superconducting density of states in the Al electrode is used as a detector for the spin polarization. Thermal robustness of the polarization, which is of key importance for the performance of magnetic tunnel junction devices, is demonstrated for post-deposition anneal temperatures up to 500 o C with Co and Co 90 Fe 10 top electrodes, independent of the presence of an FeMn layer on top of the ferromagnet

  3. Prospect of polarized targets in electron rings

    International Nuclear Information System (INIS)

    Holt, R.J.

    1984-01-01

    The feasibility of performing electron scattering experiments with polarized targets in electron storage rings is discussed. Three examples of the physics which would be accessible with this novel method are given. It is noted that this new method is compatible with recent proposals for linac-stretcher-ring accelerator designs. A new method for producing a polarized hydrogen or deuterium target is proposed and some preliminary results are described. A brief summary of laser-driven polarized targets as well as conventionally-produced polarized atomic beams is included

  4. Physics results with polarized electrons at SLAC

    International Nuclear Information System (INIS)

    Prescott, C.Y.

    1996-03-01

    Polarized electron beams can play an important role in the dynamics of interactions at high energies. Polarized electron beams at SLAC have been an important part of the physics program since 1970, when they were first proposed for use in testing the spin structure of the proton. Since 1992, the SLAC linear accelerator and the SLC have operated solely with polarized electrons, providing data for tests of QCD in studies of the spin structure of the nucleon and tests of the electroweak sector of the Standard Model. In the following sections, the performance of the source is summarized, and some of the recent results using the polarized beams are discussed

  5. Acceleration of Polarized Protons to High Energy

    International Nuclear Information System (INIS)

    Roser, T.

    1999-01-01

    High energy polarized beam collisions will open up the unique physics opportunities of studying spin effects in hard processes. However, the acceleration of polarized beams in circular accelerators is complicated by the numerous depolarizing spin resonances. Using a partial Siberian Snake and a rf dipole that ensure stable adiabatic spin motion during acceleration has made it possible to accelerate polarized protons to 25 GeV at the Brookhaven AGS. Full Siberian Snakes and polarimeters are being developed for RHIC to make the acceleration of polarized protons to 250 GeV possible. A similar scheme is being studied for the 800 GeV HERA proton accelerator

  6. A polarized target for the CLAS detector

    CERN Document Server

    Keith, C D; Battaglieri, M; Bosted, P; Branford, D; Bültmann, S; Burkert, V D; Comer, S A; Crabb, D G; De Vita, R; Dodge, G; Fatemi, R; Kashy, D; Kuhn, S E; Prok, Y; Ripani, M; Seely, M L; Taiuti, M; Witherspoon, S

    2003-01-01

    We describe the design, construction, and performance of a polarized solid target for use in electron scattering experiments with the CEBAF Large Acceptance Spectrometer. Protons and deuterons are continuously polarized by microwave-induced spin-flip transitions at 1 K and 5 T. The target operated successfully during two cycles in 1998 and 2000, providing proton and deuteron polarizations as high as 96% and 46%, respectively. The unique features of the target which permit its use inside a 4 pi spectrometer are stressed. Comparison is made between the target polarization measured by the traditional method of NMR and by electron elastic scattering.

  7. Dynamic nuclear polarization of irradiated target materials

    International Nuclear Information System (INIS)

    Seely, M.L.

    1982-01-01

    Polarized nucleon targets used in high energy physics experiments usually employ the method of dynamic nuclear polarization (DNP) to polarize the protons or deuterons in an alcohol. DNP requires the presence of paramagnetic centers, which are customarily provided by a chemical dopant. These chemically doped targets have a relatively low polarizable nucleon content and suffer from loss of polarization when subjected to high doses of ionizing radiation. If the paramagnetic centers formed when the target is irradiated can be used in the DNP process, it becomes possible to produce targets using materials which have a relatively high polarizable nucleon content, but which are not easily doped by chemical means. Furthermore, the polarization of such targets may be much more radiation resistant. Dynamic nuclear polarization in ammonia, deuterated ammonia, ammonium hydroxide, methylamine, borane ammonia, butonal, ethane and lithium borohydride has been studied. These studies were conducted at the Stanford Linear Accelerator Center using the Yale-SLAC polarized target system. Results indicate that the use of ammonia and deuterated ammonia as polarized target materials would make significant increases in polarized target performance possible

  8. RHIC Polarized proton performance in run-8

    Energy Technology Data Exchange (ETDEWEB)

    Montag,C.; Bai, M.; MacKay, W.W.; Roser, T.; Abreu, N.; Ahrens, L.; Barton, D.; Beebe-Wang, J.; Blaskiewicz, M.; Brennan, J.M.; Brown, K.A.; Bruno, D.; Bunce, G.; Calaga, R.; Cameron, P.; Connolly, R.; D' Ottavio, T.; Drees, A.; Fedotov, A.V.; Fischer, W.; Ganetis, G.; Gardner, C.; Glenn, J.; Hayes, T.; Huang, H.; Ingrassia, P.; Kayran, D.A.; Kewisch, J.; Lee, R.C.; Lin, F.; Litvinenko, V.N.; Luccio, A.U.; Luo, Y.; Makdisi, Y.; Malitsky, N.; Marr, G.; Marusic, A.; Michnoff, R.; Morris, J.; Oerter, B.; Pilat, F.; Pile, P.; Robert-Demolaize, G.; Russo, T.; Satogata, T.; Schultheiss, C.; Sivertz, M.; Smith, K.; Tepikian, S.; D. Trbojevic, D.; Tsoupas, N.; Tuozzolo, J.; Zaltsman, A.; Zelenski, A.; Zeno, K.; Zhang, S.Y.

    2008-10-06

    During Run-8, the Relativistic Heavy Ion Collider (RHIC) provided collisions of spin-polarized proton beams at two interaction regions. Physics data were taken with vertical orientation of the beam polarization, which in the 'Yellow' RHIC ring was significantly lower than in previous years. We present recent developments and improvements as well as the luminosity and polarization performance achieved during Run-8, and we discuss possible causes of the not as high as previously achieved polarization performance of the 'Yellow' ring.

  9. Sentiment Polarization and Balance among Users in Online Social Networks

    DEFF Research Database (Denmark)

    Hillmann, Robert; Trier, Matthias

    2012-01-01

    Communication within online social network applications enables users to express and share sentiments electronically. Existing studies examined the existence or distribution of sentiments in online communication at a general level or in small-observed groups. Our paper extends this research...... by analyzing sentiment exchange within social networks from an ego-network perspective. We draw from research on social influence and social attachment to develop theories of node polarization, balance effects and sentiment mirroring within communication dyads. Our empirical analysis covers a multitude...... of social networks in which the sentiment valence of all messages was determined. Subsequently we studied ego-networks of focal actors (ego) and their immediate contacts. Results support our theories and indicate that actors develop polarized sentiments towards individual peers but keep sentiment in balance...

  10. CMB polarization at large angular scales: Data analysis of the POLAR experiment

    International Nuclear Information System (INIS)

    O'Dell, Christopher W.; Keating, Brian G.; Oliveira-Costa, Angelica de; Tegmark, Max; Timbie, Peter T.

    2003-01-01

    The coming flood of cosmic microwave background (CMB) polarization experiments, spurred by the recent detection of CMB polarization by the DASI and WMAP instruments, will be confronted by many new analysis tasks specific to polarization. For the analysis of CMB polarization data sets, the devil is truly in the details. With this in mind, we present details of the data analysis for the POLAR experiment, which recently led to the tightest upper limits on the polarization of the cosmic microwave background radiation at large angular scales. We discuss the data selection process, map-making algorithms, offset removal, and likelihood analysis which were used to find upper limits on the polarization. Stated using the modern convention for reporting CMB Stokes parameters, these limits are 5.0 μK on both E- and B-type polarization at 95% confidence. Finally, we discuss simulations used to test our analysis techniques and to probe the fundamental limitations of the experiment

  11. Exploring Electric Polarization Mechanisms in Multiferroic Oxides

    Energy Technology Data Exchange (ETDEWEB)

    Tyson, Trevor A. [New Jersey Institute of Technology (NJIT), Newark, NJ (United States)

    2017-01-24

    Multiferroic oxides are a class of systems which exhibit coupling between the electrical polarization and the magnetization. These materials show promise to lead to devices in which ferromagnetic memory can be written with magnetic fields or magnetic bits can be written by an electric field. The work conducted in our research focuses on single phase materials. We studied the detailed coupling of the spin and lattice correlations in these systems. In the first phase of the proposal, we explored the complex spin spiral systems and low temperature behavior of hexagonal layered REMnO3 (RE= rare earth, Y and Sc) system following the detailed structural changes which occurred on crossing into the magnetic states. The techniques were applied to other layered materials such as superconductors and thermoelectric where the same layered motif exists. The second phase of the proposal focused on understanding the mechanisms involved in the onset high temperature ferroelectricity ion hexagonal REMnO3 and at low temperature in E-Type magnetic ordered perovskite REMnO3. We wsynthesized preovskite small A site multiferroics by high pressure and high temperature methods. Detailed measurement of the structural properties and dynamics were conducted over a range of length scales from atomic to mesoscopic scale using, x-ray absorption spectroscopy, x-ray diffuse scattering, x-ray and neutron pair distribution analysis and high resolution x-ray diffraction. Changes in vibration modes which occur with the onset of polarization were probed with temperature and pressure dependent infrared absorption spectroscopy. In addition the orthorhombic system (small radius RE ions) which is believed to exhibit electronically driven ferroelectricity and is also not understood was examined. The multiple length scale synchrotron based measurements may assist in developing more detailed models of these materials and possibly lead to device applications. The experimental

  12. The polarized neutron reflectometer 'Reverans'

    Energy Technology Data Exchange (ETDEWEB)

    Radzhabov, A.K. [Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg 188300 (Russian Federation)]. E-mail: akr@pnpi.spb.ru; Gordeev, G.P. [Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg 188300 (Russian Federation); Lazebnik, I.M. [Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg 188300 (Russian Federation); Axelrod, L.A. [Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg 188300 (Russian Federation); Zabenkin, V.N. [Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg 188300 (Russian Federation)

    2007-07-15

    The polarized neutron reflectometer 'Reverans' with a vertical plane of scattering is being installed at the VVR-M reactor (Gatchina, Russia). It will be used for research on phase boundaries, interfaces and free surfaces. Systems under study can be both magnetic and nonmagnetic ones. At present the installation of the reflectometer is at the final stage. The parameters and abilities of the reflectometer are presented.

  13. Optical refraction index and polarization profile of ferroelectric thin films

    Czech Academy of Sciences Publication Activity Database

    Glinchuk, M. D.; Eliseev, E. A.; Deineka, Alexander; Jastrabík, Lubomír; Suchaneck, G.; Sandner, T.; Gerlach, G.; Hrabovský, Miroslav

    2001-01-01

    Roč. 38, 1-4 (2001), s. 101-110 ISSN 1058-4587 R&D Projects: GA MŠk LN00A015; GA ČR GA202/00/1425 Institutional research plan: CEZ:AV0Z1010914 Keywords : thin film * refraction index * polarization * film thickness Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.512, year: 2001

  14. Association of Polar Early Career Scientists Promotes Professional Skills

    Science.gov (United States)

    Pope, Allen; Fugmann, Gerlis; Kruse, Frigga

    2014-06-01

    As a partner organization of AGU, the Association of Polar Early Career Scientists (APECS; http://www.apecs.is) fully supports the views expressed in Wendy Gordon's Forum article "Developing Scientists' `Soft' Skills" (Eos, 95(6), 55, doi:10.1002/2014EO060003). Her recognition that beyond research skills, people skills and professional training are crucial to the success of any early-career scientist is encouraging.

  15. Corrosion behaviour of nickel during anodic polarization in chloride solution

    International Nuclear Information System (INIS)

    Memon, S.A.; Isani, A.A.; Memon, A.N.

    1998-01-01

    This research presents the effect of oxygen and nitrogen on the corrosion behaviour of nickel in the chloride solution, at the steady state polarized and unpolarized potentials. The additives were selected from those, which are used for bright nickel plating. It was observed that the agitation of electrolyte in a particular pH-(Cl)' range increase the potentials in comparison of the potentials to the un-agitated electrolytes. (author)

  16. Electrokinetics of Polar Liquids in Contact with Non-Polar Surfaces

    OpenAIRE

    Lin, Chih-Hsiu; Ferguson, Gregory S.; Chaudhury, Manoj K.

    2014-01-01

    Zeta potentials of several polar protic (water, ethylene glycol, formamide) as well as polar aprotic (dimethyl sulfoxide) liquids were measured in contact with three non-polar surfaces using closed-cell electro-osmosis. The test surfaces were chemisorbed monolayers of alkyl siloxanes, fluoroalkyl siloxanes and polydimethylsiloxanes (PDMS) grafted on glass slides. All these liquids exhibited substantial electrokinetics in contact with the non-polar surfaces with these observations: the electro...

  17. Myth polar light. Why sky bands, herring lightnings, and solar winds fascinate

    International Nuclear Information System (INIS)

    Hunnekuhl, Michael

    2014-01-01

    The actual state of knowledge of the polar-light research is in this illustrated volume as entertainingly as scientific-foundedly presented. The pecularities of pola lights beyond the polar-light zones as for instance in Germany are thematized and the conditions and periods, in which it there occurs, explained. Michael Hunnekuhl succeeds to mediate the fascination and emotion and simultaneously to explain the phenomena according to the latest state of science generally understandably. Which very old interpretations and descriptions are transmitted, which imaginations had men of polar lights long before the science could them explain? Hunnekuhl takes the reader along with into the world of legends and myths around the polar light. An experience report from the deeply snowed up wideness of Lapland lets everybody closely participate at a polar-light observation and feel the emotion, which it can fan. Above 70 polar-light pictures of high value and further explaining graphics show the continuously changing play of colors, supplement the explanations, and make the fascination comprehensible. Spectacular polar-light films from the international space station ISS, photographs from sun-observation satellites, as well as a polar-light film in real time are bound in the book via QR codes and make the time dimension and the dynamics of this fascinating natural spectacle alively comprehensible.

  18. Strain-engineering stabilization of BaTi O3 -based polar metals

    Science.gov (United States)

    Ma, Chao; Jin, Kui-juan; Ge, Chen; Yang, Guo-zhen

    2018-03-01

    Polar metals, which possess ferroelectriclike polar structure and conductivity simultaneously, have attracted wide interest since the first solid example, LiOs O3 (below 140 K), was discovered. However, the lack of room-temperature polar metals hinders further research and applications. Thus abundant properties of polar metals are unexplored. Here, with first-principles calculations, we report that the polar metal phase can be stabilized in the strain-engineered BaTi O3 with electron doping. The mechanism relates to the competition between the shifting of the t2 g energy levels and the narrowing of their bandwidth. Surprisingly, it is predicted that the ferroelectric-to-paraelectric transition temperature can be increased by electron doping when the strain is large enough, which holds potential for room-temperature polar metals. Our results indicate that strain engineering is a promising way to achieve BaTi O3 -based polar metals, and they should have practical significance for obtaining easily accessible, ecofriendly, and potential room-temperature polar metals.

  19. QSAT: The Satellite for Polar Plasma Observation

    Science.gov (United States)

    Tsuruda, Yoshihiro; Fujimoto, Akiko; Kurahara, Naomi; Hanada, Toshiya; Yumoto, Kiyohumi; Cho, Mengu

    2009-04-01

    This paper introduces QSAT, the satellite for polar plasma observation. The QSAT project began in 2006 as an initiative by graduate students of Kyushu University, and has the potential to contribute greatly to IHY (International Heliophysical Year) by showing to the world the beauty, importance, and relevance of space science. The primary objectives of the QSAT mission are (1) to investigate plasma physics in the Earth’s aurora zone in order to better understand spacecraft charging, and (2) to conduct a comparison of the field-aligned current observed in orbit with ground-based observations. The QSAT project can provide education and research opportunities for students in an activity combining space sciences and satellite engineering. The QSAT satellite is designed to be launched in a piggyback fashion with the Japanese launch vehicle H-IIA. The spacecraft bus is being developed at the Department of Aeronautics and Astronautics of Kyushu University with collaboration of Fukuoka Institute of Technology. Regarding the payload instruments, the Space Environment Research Center of Kyushu University is developing the magnetometers, whereas the Laboratory of Spacecraft Environment Interaction Engineering of Kyushu Institute of Technology is developing the plasma probes. We aim to be ready for launch in 2009 or later.

  20. Cross-polarization and sidelobe suppression in dual linear polarization antenna arrays

    DEFF Research Database (Denmark)

    Woelders, Kim; Granholm, Johan

    1997-01-01

    In recent years, there has been an increasing interest in dual linear polarization antennas for various purposes, e.g. polarimetric synthetic aperture radar (SAR) imaging. A key design goal for dual polarization antennas is to obtain a high cross-polarization suppression. When using standard tech...