WorldWideScience

Sample records for halls on-campus students

  1. On-campus programs to support college students in recovery.

    Science.gov (United States)

    Misch, Donald A

    2009-01-01

    The author argues that referral of alcohol-abusing college students to off-campus treatment services, although necessary for some, is not optimal for many. He advocates the implementation of comprehensive on-campus services for students committed to recovery in order to optimize their treatment while allowing them to remain in school and work towards their degree. The author suggests that such on-campus recovery services provide additional benefits to the college or university as well as to other students, and he proposes that on-campus alcohol-abusing students in recovery can serve as important opinion leaders and role models for their peers.

  2. FIRE's Guide to Free Speech on Campus. Second Edition. FIRE's Guides to Student Rights on Campus

    Science.gov (United States)

    Silverglate, Harvey A.; French, David; Lukianoff, Greg

    2012-01-01

    Since its first publication in 2005, the Foundation for Individual Rights in Education (FIRE) has distributed more than 138,000 print and online copies of its "Guide to Free Speech on Campus." In that time, FIRE's commitment to advocating on behalf of the essential rights discussed in the pages that follow has remained unwavering;…

  3. International Students' Social Network: Network Mapping to Gage Friendship Formation and Student Engagement on Campus

    Science.gov (United States)

    McFaul, Susannah

    2016-01-01

    Addressing the importance of international student engagement on campus and creating friendships with host-country nationals during their time abroad, this small-scale study explores the question of, "Are there trends in how or through what means international students are making connections with co-national, multi-national, or host-national…

  4. a comparative study of student academic performance in on-campus

    African Journals Online (AJOL)

    User

    demic performance (Cumulative Weighted Average Scores) between distance and on-campus students. ... one of the several programmes that is offered ... and women in the two courses in health care ..... cation for Business 77 (5):257-263.

  5. A Comparative Study on Cultural Attitudes of On-campus and Non-Campus Students

    Directory of Open Access Journals (Sweden)

    Vahid Shalchi

    2015-03-01

    Full Text Available This article will explore the different way of leisure and some cultural attitudes among on-campus and non-campus students. The method of this study is survey research and questionnaires have been used. The statistical population is the students under the Ministry of Science, Research and Technology’s universities and three-stage cluster sampling method was used for sampling. In the first stage among 31 provinces in Iran, 6 cities have been chosen and in the second stage a number of universities have been chosen among Public University, Payame Noor University, University of Applied Science and Technology, and Nonprofit University, and in the third stage a number of students staying in dormitories and on-campus have been chosen randomly. The sample size is 2500 people and SPSS 19 software has been utilized for data analysis. The results show that there is a considerable difference between the participants’ priorities, obstacles and opportunities in the two groups. Also there is a significant difference between on-campus and non-campus students in terms of their treatment of the most important university’s issues, important criterion in individual success and concerns about the relation between themselves and the society. On-campus students claim financial limitations as one of the most important obstacles for passing their leisure time whereas non-campus students see social supervision as the most important limitation. Moreover, there is a large gap between on-campus students to have an access to leisure facilities, with other students. The concerns between the two groups are also very different. For example on-campus students have twice more concerns on marriage whereas non-campus students have twice more concerns on immigration to foreign countries.

  6. Alcohol consumption and attitudes towards banning alcohol sales on campus among European university students.

    Science.gov (United States)

    Stock, C; Mikolajczyk, R; Bloomfield, K; Maxwell, A E; Ozcebe, H; Petkeviciene, J; Naydenova, V; Marin-Fernandez, B; El-Ansari, W; Krämer, A

    2009-02-01

    The European Commission's new health strategy for improving health at the European Union (EU) level includes tackling alcohol consumption. This study aimed to assess the prevalence of alcohol consumption and problem drinking, as well as students' attitudes towards banning the sale of alcohol on campus. In total, 5826 students from universities in seven European countries (Denmark, Germany, Spain, Lithuania, Poland, Bulgaria and Turkey) took part in this cross-sectional study. A self-administered questionnaire assessed sociodemographic information, frequency of alcohol consumption, problem drinking and attitudes towards banning the sale of alcohol on campus. The highest prevalence of drinking alcohol more than once per week was reported in Bulgarian (males 46%, females 64%) and Spanish students (males 59%, females 64%). Among those students who drank alcohol (n=3170), problem drinking (CAGE score >1) was found in 24% of males and 13% of females. Male gender, depressive moods and a low importance of good grades at university were risk factors for drinking alcohol more than once per week as well as for problem drinking. There were substantial country differences in the proportion of students who would support a ban of alcohol sales on campus (23% in Denmark, 88% in Poland). Support for a ban was higher among female students and among students who drank alcohol once or less per week. Problem drinking is a concern among students in many European countries, especially among males. Students' support for banning the sale of alcohol on campus varies between countries and should be considered in developing EU policy.

  7. Ownership versus on-campus use of mobile IT devices by university students

    NARCIS (Netherlands)

    Kobus, M.B.W.; Rietveld, P.; van Ommeren, J.N.

    2013-01-01

    This study investigated ownership and on-campus use of laptops, tablets, and smartphones, using survey information on Dutch university students. We show that 96% of students own at least one of these mobile IT devices (i.e., a laptop, tablet, or smartphone). Using econometric modelling, we also show

  8. On Campus and Online, Students Lose Weight for Credit

    Science.gov (United States)

    Lipka, Sara

    2011-01-01

    About a third of college students nationwide are overweight, and the proportion of obese students has increased, to 11.3% in 2009 from 8% in 2000, according to the American College Health Association. College students are still slimmer than other young adults, but campus officials worry about the upward trend. Many colleges feel it's their…

  9. Anxiety and Attitude of Graduate Students in On-Campus vs. Online Statistics Courses

    Science.gov (United States)

    DeVaney, Thomas A.

    2010-01-01

    This study compared levels of statistics anxiety and attitude toward statistics for graduate students in on-campus and online statistics courses. The Survey of Attitudes Toward Statistics and three subscales of the Statistics Anxiety Rating Scale were administered at the beginning and end of graduate level educational statistic courses.…

  10. Bringing alcohol on campus to raise money: impact on student drinking and drinking problems

    Science.gov (United States)

    Voas, Robert B.; Johnson, Mark; Turrisi, Robert J.; Taylor, Dexter; Honts, Charles Robert; Nelsen, Lisa

    2010-01-01

    Aims Universities are striving to raise funds, often attracting spectators by selling alcohol at campus events. This study evaluates the effect of a policy change on student drinking at a large western university that had historically banned alcohol on campus but transitioned to permitting the sale of alcohol in some of its facilities. Methods Surveys of student drinking and perceptions of other students' drinking were conducted before, during and after the policy change at the transition university (TU) and compared to similar data from a control university (CU). Surveys of student drinking at on-campus and off-campus venues and observations of alcohol service practices were also conducted. Results The policy change at the TU was introduced cautiously, and sales to underage drinkers were relatively well controlled. Despite this, student drinking rose initially, then declined after 1 year. Perceptions of the amount of drinking by other students increased slightly, but there was no overall measurable increase in student drinking during the first 3 years of the new policy. Conclusions The conservative TU policy—to sell alcohol only at select events and to control sales to minors—may have limited the impact of on-campus alcohol sales on student consumption. Although the study results did not find a stable increase in student drinking, they do not necessarily support the liberalization of campus alcohol policy, because the transition is still ‘in progress’ and the final outcome has not been evaluated. PMID:18482416

  11. College Student Perceptions on Campus Alcohol Policies and Consumption Patterns

    Science.gov (United States)

    Marshall, Brenda L.; Roberts, Katherine J.; Donnelly, Joseph W.; Rutledge, Imani N.

    2011-01-01

    Environmental strategies for colleges and universities to reduce alcohol consumption among their students include the development and enforcement of campus alcohol policies. This study examines students' knowledge and attitudes toward campus alcohol policies and how they relate to alcohol consumption and alcohol social norms. A sample of 422…

  12. Atheist Students on Campus: From Misconceptions to Inclusion

    Science.gov (United States)

    Goodman, Kathleen M.; Mueller, John A.

    2009-01-01

    People who follow trends in higher education are aware of a renewed emphasis on religious plurality and spirituality on college campuses. But all the articles, conferences, and campus activities surrounding religion and spirituality rarely, if at all, acknowledge one group: students who are atheists. If colleges are to be truly inclusive, they…

  13. College Students' Perceptions of Slut-Shaming Discourse on Campus

    Science.gov (United States)

    Almazan, Vanessa A.; Bain, Steve F.

    2015-01-01

    The purpose of this study was to understand the college students' perceptions of slut-shaming discourse. The research indicated that there was a strong correlation between cultural expectations and slut-shaming. According to the results, the perceptions of slut-shaming are influenced by aspects such as: class, culture, media, gender, feminism,…

  14. Key Determinants of Waste Separation Intention among Students on Campus

    Directory of Open Access Journals (Sweden)

    Ayob Siti Fadzilah

    2016-01-01

    Full Text Available This study aims to identify the key determinants of waste separation intention among the students in Universiti Teknologi Malaysia (UTM. As reported in World Bank Report, generation of global municipal solid waste are approximately 1.3 billion tonnes per year, and it will increase approximately 2.2 billion tonnes per year by 2025. Similar trend in Malaysia which approximately eight million tonnes of municipal solid waste is produced daily. Upward trend of the solid waste generated is contributed by various forces including growth, increase of population, residents attitude and rapid urbanisation in the country. Considering the negative impacts from increase of waste generated in the country such as environmental degradation, separate the waste at its source can increase recycling rate and hence reduce waste generation. In the 11th Malaysia Plan, the government has urged the nation to actively practice waste separation. Understanding the determinants influencing waste separation behaviour can lead to effective waste reduction among the targeted group. This study adopted the Theory of Planned Behaviour as the fundamental framework. The key determinants of waste separation behaviour are attitude, subjectives norm, and perceived behavioural control. An elicitation survey has been conducted to explore the students’s beliefs relative to the waste separation behaviour. The empirical data collected were analysed using structural equation modelling (SEM assisted by SmartPLS software. The result shows that only determinants are significant towards intention which are attitude and Perceived Behavioural Control while Subjective Norm is not. The results of the study is significance to the organisation as identification of the determinants that influence waste separation intention contributes to a more focused waste separation programme that allign to Malaysia’s objective towards a sustainable developing country.

  15. A Comparison of the Performance of Online versus Traditional On-Campus Earth Science Students on Identical Exams

    Science.gov (United States)

    Werhner, Matthew J.

    2010-01-01

    In this paper I compare the performance of online versus traditional on-campus students on identical exams in an earth science class. The number of college level distance learning classes offered online continues to increase as they offer greater scheduling flexibility to students, they appeal to students who like to work independently, and allow…

  16. Social Networking: Engaging Prospective and Admitted African American and Other Minority Students before They Arrive on Campus

    Science.gov (United States)

    Wortham, Forest B.

    2013-01-01

    Planning programs with learning outcomes that address diversity issues on campus can become fairly routine--a "plug and play" task--for a director of multicultural student affairs at a private, religious, predominantly white liberal arts university. However, connecting with African American and other minority students when they arrived on campus…

  17. Active Transportation to and on Campus is Associated With Objectively Measured Fitness Outcomes Among College Students.

    Science.gov (United States)

    Bopp, Melissa; Bopp, Christopher; Schuchert, Megan

    2015-03-01

    Active transportation (AT) has been associated with positive health outcomes, yet limited research has addressed this with college students, a population at-risk for inactivity. The purpose of this study was to examine the relationship between AT behavior and objectively measured fitness outcomes. A volunteer, convenience sample (n = 299) of college students from a large northeastern university completed a survey about their AT habits to and on campus and psychosocial constructs related to AT and participated in a laboratory-based fitness assessment (cardiovascular endurance, muscular strength and endurance, flexibility, body composition).Off-campus students were dichotomized as nonactive (0-1 AT trips/day) or active travelers (> 1 AT trips/day) to campus; t-tests compared nonactive and active travelers for psychosocial and fitness variables. Students were 56.3% male, 79.2% non-Hispanic White, and primarily living off-campus (87%). Most students (n = 177, 59.2%) reported active travel between classes. Off-campus students were primarily active travelers (76.1%). Active travelers to campus had greater cardiovascular fitness (P = .005), were more flexible (P = .006) and had lower systolic blood pressure (P = .05) compared with nonactive travelers. This study documents a relationship between AT behavior and objectively measured fitness among college students and provides a rationale for targeting this behavior as a method for improving health outcomes.

  18. Frequent Experience of LGBQ Microaggression on Campus Associated With Smoking Among Sexual Minority College Students.

    Science.gov (United States)

    Ylioja, Thomas; Cochran, Gerald; Woodford, Michael R; Renn, Kristen A

    2018-02-07

    Lesbian, gay, bisexual, or queer/questioning (LGBQ) microaggressions refer to often-unintentional insults, assaults, and invalidations that denigrate sexual minorities. While experiencing hostile discrimination and violence has previously been associated with elevated rates of smoking cigarettes for LGBQ college students, the relationship between LGBQ microaggressions and smoking is unknown. Data from a national anonymous online survey of sexual and gender minority college students were used to examine the relationship between past month cigarette smoking and interpersonal LGBQ microaggressions. Multivariable logistic regression assessed the relationship between smoking and frequent (chronic) experiences of microaggressions, using a hierarchical procedure to control for demographics, predictors of smoking, and academic factors. Past year frequent LGBQ microaggression was reported by 48% of respondents and was more common among students who smoked in past 30 days. Experiencing past year physical violence was reported by 15% and did not differ by smoking status. Past year frequent experience of microaggressions was associated with increased odds of 1.72 (95% CI 1.03-2.87) for past 30-day smoking after adjusting for age, gender, race, socioeconomic indicators, alcohol misuse, physical violence, as well as academic stress and engagement. The results indicate that frequently experiencing LGBQ microaggressions is a risk factor for LGBQ college students smoking cigarettes. The mechanisms underlying this relationship require additional research, as does identifying positive coping strategies and institutional strategies to address LGBQ microaggressions on campuses. Tobacco control efforts should consider the impact of microaggression on the social environment for the prevention and treatment of tobacco use among LGBQ individuals. Microaggressions related to sexual minority identity include subtle forms of discrimination experienced during daily interactions that can create

  19. "Social jetlag" in morning-type college students living on campus: implications for physical and psychological well-being.

    Science.gov (United States)

    Lau, Esther Yuet Ying; Wong, Mark Lawrence; Ng, Eddie Chi Wai; Hui, Chi-chiu Harry; Cheung, Shu Fai; Mok, Doris Shui Ying

    2013-08-01

    Although on-campus residence allows easier access to campus facilities, existing studies showed mixed results regarding the relationship between college residence and students' well-being indicators, such as sleep behaviors and mood. There was also a lack of studies investigating the role of chronotype in the relationship between on-campus residence and well-being. In particular, the temporal relationships among these factors were unclear. Hence, this longitudinal study aims to fill in these gaps by first reporting the well-being (measured in terms of mood, sleep, and quality of life) among students living on and off campus across two academic semesters. We explored factors predicting students' dropout in university residences. Although students living on campus differ in their chronotypes, activities in campus residence (if any) are mostly scheduled in the nighttime. We therefore tested if individual differences in chronotype interact with campus residence in affecting well-being. Our final sample consisted of 215 campus residents and 924 off-campus-living students from 10 different universities or colleges in Hong Kong or Macau. Their mean age was 20.2 years (SD=2.3); 6.5% of the participants are female. Participants completed self-reported questionnaires online on their sleep duration, sleep quality, chronotype, mood, and physical and psychological quality of life. Across two academic semesters, we assessed if students living on and off campus differed in our well-being measures after we partialed out the effects of demographic information (including age, sex, family income, and parents' education) and the well-being measures at baseline (T1). The results showed that, campus residents exhibited longer sleep duration, greater sleep efficiency, better sleep quality, and less feeling of stress than off-campus-living students. From one semester to the next, around 10% of campus residents did not continue to live on campus. Logistic regression showed that a morning

  20. Student Hunger on Campus: Food Insecurity Among College Students and Implications for Academic Institutions.

    Science.gov (United States)

    Payne-Sturges, Devon C; Tjaden, Allison; Caldeira, Kimberly M; Vincent, Kathryn B; Arria, Amelia M

    2018-02-01

    To estimate the prevalence of food insecurity among students at a large mid-Atlantic publicly funded university; examine the association between food insecurity, demographic characteristics, potential financial risk factors, and self-reported physical and mental health and academic performance; and identify possible risk factors for food insecurity. Cross-sectional survey. Large, public mid-Atlantic university. Two hundred thirty-seven undergraduate students. US Department of Agriculture (USDA) 18-item Household Food Security Survey Module (HFSSM) and questions on demographics, student status, economic factors, housing stability, living arrangements, academic performance, and self-rated physical health and depression symptoms. Multivariate logistic regression analysis. Among students surveyed, 15% were food insecure; an additional 16% were at risk of food insecurity. Students who were African American, other race/ethnicity, receiving multiple forms of financial aid, or experiencing housing problems were more likely to be food insecure or at the risk of food insecurity (Adjusted Odds Ratio [AOR] = 4.00, 95% confidence interval [CI] = 1.83-8.71, P value health concern that might have implications for academic performance, retention, and graduation rates. Universities that measure food insecurity among their students will be better positioned to advocate for policy changes at state and federal levels regarding college affordability and student financial assistance.

  1. A Residential Paradox?: Residence Hall Attributes and College Student Outcomes

    Science.gov (United States)

    Bronkema, Ryan; Bowman, Nicholas A.

    2017-01-01

    The researchers of this brief observed that few environments have the potential to shape the outcomes of college students as much as residence halls. As a result, residence halls have the capacity to foster a strong sense of community as well as other important outcomes such as college satisfaction and academic achievement. However, given the high…

  2. Mental Health and Military-Connected Students on Campus: Culture, Challenges, and Success

    Science.gov (United States)

    Bonar, Ted C.

    2016-01-01

    This chapter provides an overview of common challenges faced by military-connected students on university campuses. The characteristics, culture, and experiences of service members and veterans are described through vignettes based on military-connected students.

  3. College Students with Physical Disabilities: Common on Campus, Uncommon in the Literature

    Science.gov (United States)

    Gelbar, Nicholas W.; Madaus, Joseph W.; Lombardi, Allison; Faggella-Luby, Michael; Dukes, Lyman

    2015-01-01

    College students with physical disabilities were among the first students to receive disability supports in higher education in the United States, and the earliest journal articles in disability services focused almost exclusively on this cohort. As more students with a range of disability types have accessed higher education over the past 25…

  4. Narratives Lost in the Box: The Trichotomy of Latina Student Identity Transition Stages Due to Mass Media and On-Campus Stereotyping

    Science.gov (United States)

    Martinez-Vogt, Emily

    2017-01-01

    This theoretical paper is based on a larger study focused on understanding the experiences of Latina community college students. The purpose of this paper is to expand upon the Silence to Resilience Model, which involves four phases that Latinas encounter upon or throughout their transition to community college including: (1) Racism on campus, (2)…

  5. Prophylactic procurement of university students in Southern Ethiopia: stigma and the value of condom machines on campus.

    Science.gov (United States)

    Wells, Christopher J; Alano, Abraham

    2013-01-01

    Risky sexual behavior among Ethiopian university students, especially females, is a major contributor to young adult morbidity and mortality. Ambaw et al. found that female university students in Ethiopia may fear the humiliation associated with procuring condoms. A study in Thailand suggests condom machines may provide comfortable condom procurement, but the relevance to a high-risk African context is unknown. The objective of this study was to examine if the installation of condom machines in Ethiopia predicts changes in student condom uptake and use, as well as changes in procurement related stigma. Students at a large urban university in Southern Ethiopia completed self reported surveys in 2010 (N  = 2,155 surveys) and again in 2011 (N =  2,000), six months after the installation of condom machines. Mann-Whitney and Chi-square tests were conducted to evaluate significant changes in student sexual behavior, as well as condom procurement and associated stigma over the subsequent one year period. After installing condom machines, the average number of trips made to procure condoms on-campus significantly increased 101% for sexually active females and significantly decreased 36% for sexually active males. Additionally, reports of condom use during last sexual intercourse showed a non-significant 4.3% increase for females and a significant 9.0% increase for males. During this time, comfort procuring condoms and ability to convince sexual partners to use condoms were significantly higher for sexually active male students. There was no evidence that the condom machines led to an increase in promiscuity. The results suggest that condom machines may be associated with more condom procurement among vulnerable female students in Ethiopia and could be an important component of a comprehensive university health policy.

  6. Colleges Debating Their Proper Role in Curbing Pornography on Campus.

    Science.gov (United States)

    Koberstein, Jennifer A.

    1986-01-01

    Campus and administrative concerns about pornography on campus are increasing, including controversy over sale of periodicals on campus, screening of sexually explicit movies, student participation in films as actors, and education of students about social issues related to pornography. (MSE)

  7. College students identify university support for basic needs and life skills as key ingredient in addressing food insecurity on campus

    Directory of Open Access Journals (Sweden)

    Tyler D. Watson

    2017-09-01

    Full Text Available A recent University of California (UC systemwide survey showed that 42% of UC college students experience food insecurity, consistent with other studies among U.S. college students. As part of UC's efforts to understand and address student food insecurity, we conducted 11 focus group interviews across four student subpopulations at UC Los Angeles (n = 82. We explored student experiences, perceptions and concerns related to both food insecurity and food literacy, which may help protect students against food insecurity. Themes around food insecurity included student awareness about food insecurity, cost of university attendance, food insecurity consequences, and coping strategies. Themes around food literacy included existing knowledge and skills, enjoyment and social cohesion, and learning in the dining halls. Unifying themes included the campus food environment not meeting student needs, a desire for practical financial and food literacy “life skills” training, and skepticism about the university's commitment to adequately address student basic needs. The results of this study broadly suggest there is opportunity for the university to address student food insecurity through providing food literacy training, among other strategies.

  8. Learning about gender on campus: an analysis of the hidden curriculum for medical students.

    Science.gov (United States)

    Cheng, Ling-Fang; Yang, Hsing-Chen

    2015-03-01

    Gender sensitivity is a crucial factor in the provision of quality health care. This paper explores acquired gendered values and attitudes among medical students through an analysis of the hidden curriculum that exists within formal medical classes and informal learning. Discourse analysis was adopted as the research method. Data were collected from the Bulletin Board System (BBS), which represented an essential communication platform among students in Taiwan before the era of Facebook. The study examined 197 gender-related postings on the BBS boards of nine of 11 universities with a medical department in Taiwan, over a period of 10 years from 2000 to 2010. The five distinctive characteristics of the hidden curriculum were as follows: (i) gendered stereotypes of physiological knowledge; (ii) biased treatment of women; (iii) stereotyped gender-based division of labour; (iv) sexual harassment and a hostile environment, and (v) ridiculing of lesbian, gay, bisexual and transgender (LGBT) people. Both teachers and students co-produced a heterosexual masculine culture and sexism, including 'benevolent sexism' and 'hostile sexism'. As a result, the self-esteem and learning opportunities of female and LGBT students have been eroded. The paper explores gender dynamics in the context of a hidden curriculum in which heterosexual masculinity and stereotyped sexism are prevalent as norms. Both teachers and students, whether through formal medical classes or informal extracurricular interactive activities, are noted to contribute to the consolidation of such norms. The study tentatively suggests three strategies for integrating gender into medical education: (i) by separating physiological knowledge from gender stereotyping in teaching; (ii) by highlighting the importance of gender sensitivity in the language used within and outside the classroom by teachers and students, and (iii) by broadening the horizons of both teachers and students by recounting examples of the lived

  9. Reducing Sexual Violence on Campus: The Role of Student Leaders as Empowered Bystanders

    Science.gov (United States)

    Banyard, Victoria L.; Moynihan, Mary M.; Crossman, Maria T.

    2009-01-01

    Sexual violence is a widespread problem for college communities. Students, faculty, and staff are increasingly involved in prevention efforts. To date, however, evaluation of sexual violence prevention programs has shown mixed results. One promising new practice teaches segments of college communities to be engaged, positive bystanders. It aims to…

  10. Therapy Dogs on Campus: A Counseling Outreach Activity for College Students Preparing for Final Exams

    Science.gov (United States)

    Barker, Sandra B.; Barker, Randolph T.; Schubert, Christine M.

    2017-01-01

    A university counseling center engaged a therapy dog program for an outreach activity to reduce stress as students prepare for final exams at a large culturally diverse university. This article describes the rationale, planning, and implementation of the activity; presents an evaluation summary; and provides recommendations and implications for…

  11. How Students Rate the Quality Service Climate on Campus. National Research Report, 2012

    Science.gov (United States)

    Noel-Levitz, Inc, 2012

    2012-01-01

    How satisfied are students with the service they receive--and how important is it to them? This report documents significant strides that colleges and universities have made in recent years to improve service quality and their overall campus climate, yet also finds that campuses still have room for improvement. A few highlights: (1) While progress…

  12. How Students Rate the Quality Service Climate on Campus. National Research Report, 2011

    Science.gov (United States)

    Noel-Levitz, Inc, 2011

    2011-01-01

    How satisfied are students with the service they receive--and how important is it to them? This report documents significant strides that colleges and universities have made in recent years to improve service quality and their overall campus climate, yet also finds that campuses still have room for improvement. A few highlights: (1) While progress…

  13. Academic Benefits of On-Campus Employment to First-Year Developmental Education Students.

    Science.gov (United States)

    Wilkie, Carolyn; Jones, Marquita

    1994-01-01

    A study of 1,012 college freshmen admitted through a developmental studies program and offered employment through a highly structured program of up to 8 work hours/week found those taking maximum advantage of the work opportunity had higher achievement and retention rates than others. Differences by race and gender, and student perceptions, are…

  14. The Role of Language in Interactions with Others on Campus for Rural Appalachian College Students

    Science.gov (United States)

    Dunstan, Stephany Brett; Jaeger, Audrey J.

    2016-01-01

    Dialects of English spoken in rural, Southern Appalachia are heavily stigmatized in mainstream American culture, and speakers of Appalachian dialects are often subject to prejudice and stereotypes which can be detrimental in educational settings. We explored the experiences of rural, Southern Appalachian college students and the role speaking a…

  15. College Students' Experiences and Perceptions of Harassment on Campus: An Exploration of Gender Differences

    Science.gov (United States)

    Reason, Robert D.; Rankin, Susan R.

    2006-01-01

    Using a campus climate assessment instrument developed by Rankin (1998), we surveyed students (N = 7,347) from 10 campuses to explore the different experiences with harassment and campus climates reported by men and women. Both men and women reported experiencing harassment, although women experienced harassment at statistically significantly…

  16. Involving Students in Residence Halls in Hong Kong

    Science.gov (United States)

    Ting, S. Raymond; Chan, Rebecca; Lee, Esther

    2016-01-01

    This article reports a study based on A. W. Astin's (1984) involvement theory applied in residence halls at a public university in Hong Kong, China. The resident students who were involved as participants or student leaders in this study were found to be better developed in terms of leadership, career development, multicultural experience,…

  17. Personal exposure of graduate students attending the college of natural sciences or social sciences to volatile organic compounds on campus.

    Science.gov (United States)

    Jo, Wan-Kuen; Kim, Jong-Dae

    2010-11-01

    The present study measured the levels of 24 selected volatile organic compounds (VOCs) in the personal air samples obtained from graduate students attending the college of natural sciences (GSNSs) or social science (GSSSs) during their daily activities on campus along with associated indoor and outdoor air samples. In addition, the sources of their personal exposure were characterized using multivariate statistical models. In the personal samples of GSNSs and GSSSs, 16 and 15 different VOCs were always detected, respectively. The personal exposure of five chlorinated hydrocarbons and six aromatics was significantly higher for GSNSs than for GSSSs. Consistently, the indoor levels of these compounds were higher for GSNSs (in research and laboratory rooms) than for GSSSs (in research rooms). However, the personal exposure of two aromatic VOCs (1,2,4- and 1,3,5-trimethylbenzene) was higher for GSSSs. Moreover, the personal exposure of the five chlorinated and six aromatic compounds was significantly correlated with VOC concentrations both in the research and laboratory rooms of GSNSs and with those in the research rooms of GSSSs. For certain VOCs, outdoor sources were also a major contributor to the personal exposure of both GSNSs and GSSSs. The multivariate models identified five factors that accounted for 81% of the total variance and four factors that explained 76% of the total variance. It was further suggested that multiple indoor sources in research rooms such as office equipment, building finishing materials, and air fresheners were the main source for the personal exposure to VOCs for GSNSs, whereas building finishing materials were the main source for GSSSs. Copyright © 2010 Elsevier Ltd. All rights reserved.

  18. Effectiveness of Pricing Strategies on French Fries and Fruit Purchases among University Students: Results from an On-Campus Restaurant Experiment.

    Science.gov (United States)

    Deliens, Tom; Deforche, Benedicte; Annemans, Lieven; De Bourdeaudhuij, Ilse; Clarys, Peter

    2016-01-01

    This study examined the effect of a 10 and 20% meal price increase when choosing French fries and a 10 and 20% meal price reduction when choosing fruit for dessert on university students' purchasing behaviour in an on-campus restaurant. The moderating effect of gender was also investigated. Secondly, this study aimed at gaining further insight into reasons why these price manipulations did or did not change students' purchasing behaviour. This two-phased mixed-methods study was conducted in a Belgian on-campus university restaurant with approximately 1200 to 1300 student visitors per day. In a first phase (French fries experiment), data were collected during a control week (no price manipulation) and two separate intervention weeks (10 and 20% meal price increase when students chose French fries). In a second phase (fruit experiment), following the same protocol but carried out a few weeks later, meal prices were reduced by 10 and 20% when students chose fruit for dessert. French fries and fruit sale counts relative to the total number of items sold were used as outcome measure. Short interviews were conducted in convenient subsamples of student customers to assess influences on food choice. Increasing the meal price by 10 and 20% when choosing French fries was associated with respective 10.9 and 21.8% absolute reductions in French fries purchases, while reducing the meal price by 10 and 20% when choosing fruit for dessert was associated with absolute increases in fruit purchases of respectively 25.1 and 42.4% (all pprice, food/taste preference, eating habits, health, availability and accessibility, and body satisfaction influenced students' food choices, with taste being the most frequently mentioned factor. Pricing may be a promising strategy to improve university students' eating behaviour. The likelihood of intervention success may increase when combining pricing strategies with offering healthy, tasty and meal matching starchy alternatives to French fries and

  19. For Members Only: Feminism on Campus Today

    Science.gov (United States)

    Agness, Karin L.

    2010-01-01

    The influence of contemporary feminism in the classroom and on campus is widespread, and student clubs, women's centers, and women's studies departments often exclude women who hold traditional views. In this article, the author takes a look at how this influence evolved and describes the very successful actions she took as a student to challenge…

  20. Effectiveness of Pricing Strategies on French Fries and Fruit Purchases among University Students: Results from an On-Campus Restaurant Experiment.

    Directory of Open Access Journals (Sweden)

    Tom Deliens

    Full Text Available This study examined the effect of a 10 and 20% meal price increase when choosing French fries and a 10 and 20% meal price reduction when choosing fruit for dessert on university students' purchasing behaviour in an on-campus restaurant. The moderating effect of gender was also investigated. Secondly, this study aimed at gaining further insight into reasons why these price manipulations did or did not change students' purchasing behaviour.This two-phased mixed-methods study was conducted in a Belgian on-campus university restaurant with approximately 1200 to 1300 student visitors per day. In a first phase (French fries experiment, data were collected during a control week (no price manipulation and two separate intervention weeks (10 and 20% meal price increase when students chose French fries. In a second phase (fruit experiment, following the same protocol but carried out a few weeks later, meal prices were reduced by 10 and 20% when students chose fruit for dessert. French fries and fruit sale counts relative to the total number of items sold were used as outcome measure. Short interviews were conducted in convenient subsamples of student customers to assess influences on food choice.Increasing the meal price by 10 and 20% when choosing French fries was associated with respective 10.9 and 21.8% absolute reductions in French fries purchases, while reducing the meal price by 10 and 20% when choosing fruit for dessert was associated with absolute increases in fruit purchases of respectively 25.1 and 42.4% (all p<0.001. No moderating effect of gender was detected. Besides price, food/taste preference, eating habits, health, availability and accessibility, and body satisfaction influenced students' food choices, with taste being the most frequently mentioned factor.Pricing may be a promising strategy to improve university students' eating behaviour. The likelihood of intervention success may increase when combining pricing strategies with offering

  1. Effects of a new parallel primary healthcare centre and on-campus training programme on history taking, physical examination skills and medical students' preparedness: a prospective comparative study in Taiwan.

    Science.gov (United States)

    Yang, Ying-Ying; Wang, Shuu-Jiun; Yang, Ling-Yu; Lirng, Jiing-Feng; Huang, Chia-Chang; Liang, Jen-Feng; Lee, Fa-Yauh; Hwang, Shinn-Jang; Huang, Chin-Chou; Kirby, Ralph

    2017-09-25

    The primary healthcarecentre (PHCC) is the first place that medical students experience patient contact. Usually, medical students are frustrated by a lack of proper skills training for on-campus history taking (HT), physical examination (PE) and self-directed learning (SDL) to prepare for their PHCC and inhospital patient contact. For pre-clerks, this study aims to compare the effectiveness of PHCC training and PHCC training in combination with on-campus HT and PE training modules (PHCC+on-campus) on their clerkship preparedness. This comparative study utilised prospective, consecutive, end of pre-clerkship group objective structured clinical examination (GOSCE), beginning of clerkship OSCE and self-administered Preparation for Hospital Practice Questionnaire (PHPQ). 128 pre-clinical clerk volunteers (64 each year) receiving PHCC training (7 week PHCCtraining in addition to 7 week assignment based group learning, academic year 2014, controls) and PHCC training in combination with on-campus module training (academic year 2015, 7 week PHCCtraining in addition to 7 week on-campus sessions) were sequentially assessed before the module (week 1), at the end of the module (week 14) and at the beginning of clerkship (week 25). For overall HT and PE skills, both PHCC and PHCC+on-campus module trained pre-clerks performed better on OSCE than GOSCE. Additionally, the improvement was accompanied by higher self-reported PHPQ scores in 'confidence/coping' and 'SDL' domains. At the end of the pre-clerkship and the beginning of the clerkship stages, the degree of improvement in preparedness in 'confidence/coping' and 'SDL' domains was higher for those in the PHCC+on-campus group than for those in the PHCC group. Among the PHCC+on-campus module participants, a positive association was observed between high mean PHPQ-SDL scores and high OSCE scores. Our study suggests that the PHCC+on-campus module, which is paired faculty led and pre-trained dyad student assisted, is

  2. Alcohol Trajectories over Three Years in a Swedish Residence Hall Student Population

    Directory of Open Access Journals (Sweden)

    Henriettae Ståhlbrandt

    2010-03-01

    Full Text Available Although it is known that college students have a high alcohol consumption, less is known about the long-term drinking trajectories amongst college students and, in particular, students living in residence halls, known to be high-risk drinkers. Over four consecutive years, the drinking habits of 556 Swedish residence hall students were analyzed. The main instruments for measuring outcome were AUDIT (Alcohol Use Identification Disorders Test, SIP (Short Index of Problems and eBAC (estimated Blood Alcohol Concentration. The drinking trajectories among Swedish residence hall students showed stable and decreasing drinking patterns, with age and gender being predictors of group membership.

  3. Blended Learning on Campus

    DEFF Research Database (Denmark)

    Heilesen, Simon; Nielsen, Jørgen Lerche

    2004-01-01

    On the basis of a large-scale project implementing information and communication technology at Roskilde University, Denmark, this paper discusses ways of introducing technology-based blended learning in academic life. We examine some examples of use of systems for computer-mediated collabora......-tive learning and work in Danish Open University education as well as in courses on campus. We further suggest some possi-bilities for using technology in innovative ways, arguing that innovation is to be found, not in isolated instantiations of sys-tems, but in the form of a deliberate integration of all...... relevant ICT-features as a whole into the learning environment....

  4. Assessing Student Attitudes Towards Science in an Adaptive Online Astrobiology Course: Comparing Online and On-Campus Undergraduates

    Science.gov (United States)

    Buxner, S.; Perera, V.; Mead, C.; Horodyskyj, L.; Semken, S. C.; Lopatto, D.; Anbar, A. D.

    2016-12-01

    General-education Science, Technology, Engineering, and Mathematics (STEM) courses are considered essential to a college education, in part, to train students to think critically and to make informed decisions about complex scientific issues such as climate change and public health. Therefore, the goals of these STEM courses go beyond content knowledge to include generating positive attitudes towards science, developing competence in evaluating scientific information in everyday life, and understanding the nature of science. The Classroom Undergraduate Research Experience (CURE) survey is frequently used to measure these attitudes, but it has not previously been used in an online, general education course. In this work, we administered the CURE survey for three semesters (N = 774) before and after completion of an online astrobiology course called Habitable Worlds. We compare students taking this course as part of fully-online degree programs (o-course) with those taking it as part of traditional undergraduate programs (i-course). More females and older students were among the o-course group, while overall the course had more white students than the Arizona State University average. Mean course grades were similar between the two groups but attitudes toward science differred significantly. O-course students began the course with more positive attitudes than i-course students, and o-course students also showed more positive changes at the end of the course. These differences suggest lesser intrinsic motivation among the i-course students. Additionally, pre-course attitudes correlated with final course grade for o-course students, but not for i-course students, which implies that success among o-course students is influenced by different factors than i-course students. Thus, effective student support strategies may differ for online-only students. Future work will include student interviews to better calibrate the CURE survey to online science courses.

  5. Know Your Rights on Campus: A Guide on Racial Profiling, and Hate Crime for International Students in the United States.

    Science.gov (United States)

    Harvard Civil Rights Project, Cambridge, MA.

    This guide to the rights of international students explains racial profiling and hate crimes. Since the terrorist attacks of September 11, 2001, many immigrants and international students have experienced heightened scrutiny and outright discrimination. Racial profiling refers to the reliance by law enforcement officers on a person's ethnicity,…

  6. Power quality on campus

    Energy Technology Data Exchange (ETDEWEB)

    Copper Development Association

    2011-05-15

    The Maria Stata Center on the campus of the Massachusetts Institute of Technology (MIT) is home to the Computer Science and Artificial Intelligence Laboratory (CSAIL), the Laboratory for Information and Decision Systems (LIDS) and the Department of Linguistics and Philosophy. Computers and networks are everywhere on campus and the electrical infrastructure, mainly made of copper, ensures the highest level of power quality. The copper-based grounding system helps stabilize the wiring system and several K-rated transformers help accommodate harmonic currents and improve energy efficiency. Separation from sensitive and non-sensitive branch circuits helps to shield sensitive equipment from electrical noise, and the installation of transient voltage surge suppression equipment assures maximum protection from voltage surges. .

  7. Well-Being on Campus: Testing the Effectiveness of an Online Strengths-Based Intervention for First Year College Students

    Science.gov (United States)

    Koydemir, Selda; Sun-Selisik, Z. Eda

    2016-01-01

    The present research examined the effectiveness of an 8-week online strengths-based intervention in promoting subjective and psychological well-being of first year university students. The intervention was composed of five modules pertaining to (a) finding and cultivating on character strengths, (b) regulation of emotions and increasing positive…

  8. Students' Sense of Community in Residence Halls, Social Integration, and First-Year Persistence.

    Science.gov (United States)

    Berger, Joseph B.

    1997-01-01

    Used concepts from community psychology literature to elaborate a revised version of Tinto's model of individual student departure. Employed a longitudinal analysis of 718 college students. Results indicate that students' sense of community in their residence halls was a source of social integration and a precursor to student departure decisions.…

  9. Health dynamics in camps and on campuses: stressors and coping strategies for wellbeing among labourers and students in Cameroon

    Science.gov (United States)

    Maat, Harro; Vaandrager, Lenneke; Koelen, Maria

    2018-01-01

    ABSTRACT Purpose: For many people living in low-income countries, poverty implies an increased exposure to conditions that threaten health and wellbeing as well as reduced capacity to maintain health. Despite the challenging conditions caused by poverty, people may consider themselves healthy because they have learned to cope with their situation probably as a result of life experiences which expose people to both challenges and potential solutions. In this paper we present results from studying health and wellbeing challenges and mechanisms to cope with challenges among two different groups of people who are living under conditions of poverty: workers of the Cameroon Development Corporation (CDC) and students of the university of Buea and the university of Yaoundé. Methods: We performed a cross-sectional study, interviewing 21 CDC workers and 21 students. Results Our study reveals context-specific stressors emerging from poor work conditions and study pressure as well as non-context-specific stressors perceived by respondents as living conditions, poor healthcare and financial uncertainty. Respondents devised coping mechanisms to overcome exactly those stressors such as searching for additional money sources, preventive action towards hazardous living conditions and alternative medical support. Conclusion: We conclude that supporting and promoting such avenues is essential for enhanced and continuous coping with stressors. PMID:29436294

  10. Students' Perceptions of the Residence Hall Living Environment at Kuwait University

    Science.gov (United States)

    Al Kandari, Nabila

    2007-01-01

    The purpose of this study is to explore students' perceptions of the residence hall living environment at Kuwait University. The researcher developed a questionnaire for this purpose that included 36 items. The sample of the study consisted of 191 residential students, of whom 98 were male and 93 were female. The research findings indicated that:…

  11. Handy Cash on Campus.

    Science.gov (United States)

    Wiens, Janet

    2000-01-01

    Explores how the installation of independent ATMs on college campuses, often operated by the institution, helps provide students with a greater level of service while potentially increasing bookstore and other business revenue. Several examples are discussed. (GR)

  12. Hassles on Campus.

    Science.gov (United States)

    Elliott, Timothy R.; And Others

    1989-01-01

    Examined frequently occurring hassles among college students (n=366) at rural university, suburban community college, and urban university. Identified several stressful hassles that were common across settings. Most frequently reported hassle (troublesome thoughts about future) was common among both males and females. Men reported more problems…

  13. Mobile Phone on Campus

    Institute of Scientific and Technical Information of China (English)

    周成

    2005-01-01

    Communication revolution has brought a great convenience to modem society and people. Especially, the occurrence of mobile phone, in away, has changed the world where we live. Maybe the mobile phone was a luxury for only a decade ago. Now, it is no exaggeration4 to say that the difference between the parts and the present is as vast as that between earth and heaven. With no exception6, campus students also fall into the category called “cell-phone school”.

  14. Visitation to Natural Areas on Campus and Its Relation to Place Identity and Environmentally Responsible Behaviors

    Science.gov (United States)

    Lawrence, Eva K.

    2012-01-01

    This study examined college students' visits to natural areas on campus and how these visits relate to place identity and environmentally responsible behaviors. The majority (76.5%) of the 115 participants visited the natural areas, and 55.7% of these students visited for a course requirement. Students who lived on campus, were younger, and…

  15. Emotional Support Animals, Service Animals, and Pets on Campus

    Science.gov (United States)

    Von Bergen, C. W.

    2015-01-01

    For decades, universities have been accommodating physically disabled students who require guide dogs and other types of service animals. Within the past several years, however, mentally disabled students have increasingly petitioned colleges with no-pet policies to permit them to bring their animals on campus because they need a companion or…

  16. Alcohol-induced sexual behavior on campus.

    Science.gov (United States)

    Meilman, P W

    1993-07-01

    This study investigated the prevalence of alcohol-related sexual activity on campus. Since coming to college, 35% of the students had engaged in some form of sexual activity that was influenced by drinking. Because they had been drinking, 18% had engaged in sexual intercourse, and 15% had abandoned safe-sex techniques. For the categories any form of sexual activity and abandonment of safe-sex techniques, a significantly greater percentage of women were affected by alcohol use, but this was not true for sexual intercourse. The survey showed no significant differences between undergraduate and graduate students. All three variables showed a relationship with heavier alcohol use and with binge drinking. Academic excellence was negatively correlated with alcohol-induced sexual intercourse.

  17. This Year, Colleges Recruited Students in a "Hall of Mirrors"

    Science.gov (United States)

    Hoover, Eric; Supiano, Beckie

    2009-01-01

    Admissions deans everywhere shared concerns about recruiting students during a recession as they tried to discern how, or if, the economy would affect demand for their institutions. Amid this uncertainty, colleges used many different strategies. Some recruited more here and less there. Some offered more merit aid, while others scaled back. Some…

  18. Utilizing On-Campus Foodservice Facilities as a Laboratory

    Science.gov (United States)

    Dallmeyer, Martha A.

    2012-01-01

    In 2008, the Family and Consumer Sciences Department at Bradley University recognized the need to improve the quality of the laboratory experience in foodservice classes. A hands-on, real-world, learning experience was desired. Simultaneously, the university administration wanted to provide an on-campus foodservice for students from 8:00 p.m. to…

  19. Violence on Campus: Defining the Problems, Strategies for Action.

    Science.gov (United States)

    Hoffman, Allan M., Ed.; Schuh, John H., Ed.; Fenske, Robert H., Ed.

    This book addresses issues in dealing with campus violence, including types of violence on campuses, trends in campus violence, effects of increasing concerns about campus violence, and appropriate actions by student affairs and academic administrators to ensure campus safety. The chapters are: (1) "Violent Crime in American Society" (Fernando M.…

  20. The effect of hand hygiene on illness rate among students in university residence halls.

    Science.gov (United States)

    White, Cindy; Kolble, Robin; Carlson, Rebecca; Lipson, Natasha; Dolan, Mike; Ali, Yusuf; Cline, Mojee

    2003-10-01

    Several studies have indicated a connection between hand sanitization and infection control in numerous settings such as extended care facilities, schools, and hospitals. The purpose of this study was to assess the effectiveness of both a hand-hygiene message campaign and the use of an alcohol gel hand sanitizer in decreasing the incidence of upper-respiratory illness among students living in university residence halls. This study involved a total of 430 students recruited from 4 residence halls during the fall semester at the University of Colorado at the Boulder campus. Dormitories were paired into control and product groups. In the product groups, alcohol gel hand-sanitizer dispensers were installed in every room, bathroom, and dining hall. The data were statistically analyzed for the differences between product and control groups in reported symptoms, illness rates, and absenteeism from classes. The overall increase in hand-hygiene behavior and reduction in symptoms, illness rates, and absenteeism between the product group and control group was statistically significant. Reductions in upper respiratory-illness symptoms ranged from 14.8% to 39.9%. Total improvement in illness rate was 20%. The product group had 43% less missed school/work days. Hand-hygiene practices were improved with increased frequency of handwashing through increasing awareness of the importance of hand hygiene, and the use of alcohol gel hand sanitizer in university dormitories. This resulted in fewer upper respiratory-illness symptoms, lower illness rates, and lower absenteeism.

  1. Seeking Common Ground: First-Year U.S. University Students' Experiences with Intercultural Interaction and Friendship in an On-Campus Residential Community

    Science.gov (United States)

    Gaston, Michelle Elise

    2017-01-01

    The number of international students on U.S. campuses has increased more than 84 percent over the past decade (IIE, 2016). Although it has been well-established that interaction and friendship with local students is a key element for international student adjustment to a foreign university, few studies have grappled with how these intercultural…

  2. Energy and Water Efficiency on Campus | NREL

    Science.gov (United States)

    Energy and Water Efficiency on Campus Energy and Water Efficiency on Campus NREL ensures the resiliency of our future energy and water systems through energy efficiency strategies and technologies , renewable energy, and water efficiency on the NREL campus. FY17 Energy Intensity. The South Table Mountain

  3. Lateral Transfer Students: The Role of Housing in Social Integration and Transition

    Science.gov (United States)

    Utter, Mary; DeAngelo, Linda

    2015-01-01

    Social integration for lateral transfer students (four-to-four-year) is promoted by a living environment that encourages learning about campus, connecting to resources, and developing peer groups. Interviews with 27 lateral transfer students revealed that those who had previously lived on campus had expectations that residence halls would provide…

  4. Comparing Satisfaction, Life-Stress, Coping and Academic Performance of Counselling Students in On-Campus and Distance Education Learning Environments

    Science.gov (United States)

    Furlonger, Brett; Gencic, Emilia

    2014-01-01

    Distance education students are confronted with a range of additional challenges as part of their tertiary study experience. A quantitative approach was used to identify the challenges they face, their relative levels of satisfaction, coping strategies, and academic performance. Two hundred and ninety-five students (64 male and 231 female)…

  5. Energy-related environmental and economic performance analysis of two different types of electrically heated student residence halls

    Science.gov (United States)

    Amber, Khuram Pervez; Aslam, Muhammad Waqar

    2018-03-01

    Student residence halls occupy 26% of the total area of a typical university campus in the UK and are directly responsible for 24% of university's annual CO2 emissions. Based on five years measured data, this paper aims to investigate the energy-related environmental and economic performance of electrically heated residence halls in which space heating is provided by two different types of electric heaters, that is, panel heater (PHT) and storage heater (SHT). Secondly, using statistical and machine learning methods, the paper attempts to investigate the relationship between daily electricity consumption and five factors (ambient temperature, solar radiation, relative humidity, wind speed and type of day). Data analysis revealed that electricity consumption of both halls is mainly driven by ambient temperature only, whereas SHT residence has 39% higher annual electricity bill and emits 70% higher CO2 emissions on a per square metre basis compared to the PHT residence hall.

  6. An Internet-Based Radiology Course in Medical School: Comparison of Academic Performance of Students on Campus Versus Those With Absenteeism Due to Residency Interviews.

    Science.gov (United States)

    Alexander, Andrew George; Deas, Deborah; Lyons, Paul Eric

    2018-05-18

    Imaging and its optimal use are imperative to the practice of medicine, yet many students don't receive a formal education in radiology. Concurrently, students look for ways to take time away from medical school for residency interviewing. Web-based instruction provides an opportunity to combine these imperatives using online modalities. A largely Web-based course in radiology during the 4th year of medical school was evaluated both for its acceptance to students who needed to be away from campus for interviews, and its effectiveness on a nationally administered standardized test. All students were placed into a structured program utilizing online videos, online modules, online textbook assignments, and live interactive online lectures. Over half of the course could be completed away from campus. The Alliance of Medical Student Educators in Radiology test exam bank was used as a final exam to evaluate medical knowledge. Positive student feedback included the freedom to travel for interviews, hands-on ultrasound training, interactive teaching sessions, and quality Web-based learning modules. Negative feedback included taking quizzes in-person, a perceived outdated online textbook, and physically shadowing hospital technicians. Most students elected to take the course during the interview months of October through January. The Alliance of Medical Student Educators in Radiology final exam results (70.5%) were not significantly different than the national cohort (70%) who took the course in-person. Test scores from students taking the course during interview travel months were not significantly different from students who took the course before (P=.30) or after (P=.34) the interview season. Students desire to learn radiology and often choose to do so when they need to be away from campus during the fall of their 4th year of study to accomplish their residency interviews. Web-based education in radiology allows students' interview traveling and radiology course

  7. An On-Campus Botanical Tour to Promote Student Satisfaction and Learning in a University Level Biodiversity or General Biology Course

    Science.gov (United States)

    Ratnayaka, Harish H.

    2017-01-01

    Outdoor, hands-on and experiential learning, as opposed to instruction-based learning in classroom, increases student satisfaction and motivation leading to a deeper understanding of the subject. However, the use of outdoor exercises in undergraduate biology courses is declining due to a variety of constraints. Thus, the goal of this paper is to…

  8. Alcohol and drug use among sexual minority college students and their heterosexual counterparts: the effects of experiencing and witnessing incivility and hostility on campus

    Directory of Open Access Journals (Sweden)

    Woodford MR

    2012-03-01

    Full Text Available Michael R Woodford1, Amy R Krentzman2, Maurice N Gattis31School of Social Work, University of Michigan, Ann Arbor, MI, USA; 2Department of Psychiatry, University of Michigan, Ann Arbor, MI, USA; 3School of Social Work, University of Wisconsin-Madison, Madison, WI, USAPurpose: Research suggests that discrimination contributes to increased substance use among sexual minorities. Subtle discrimination and witnessing mistreatment, however, have received little attention. Using minority stress theory as a conceptual framework the authors examined the intersection of sexual orientation, experiencing and witnessing incivility and hostility, and students' alcohol and drug use. The authors hypothesized that experiencing/witnessing incivility/hostility would mediate the relationship between sexual minority status and drinking and drug use, as well as problematic use of these substances.Methods: Data were taken from a campus climate survey (n = 2497; age mean [M] = 23.19 years; 61% female; 17% sexual minorities. Controlling for demographics, logistic regressions depicted specifications for each path of the mediation analysis and bootstrapping was used to assess the significance of each sexual minority-mistreatment-drinking/drug use path.Results: Experiencing incivility mediated the relationship between sexual minority status and problematic drinking. Sexual minority college students were more likely to personally experience incivility (adjusted odds ratio [AOR] = 1.87; 95% confidence interval [CI] = 1.51–2.33, which was associated with greater odds of problematic drinking (AOR = 1.64; 95% CI = 1.35–2.00. The mediation path was significant at P < 0.001. Further, witnessing hostility mediated the relationship between sexual minority status and problematic drinking. Sexual minority college students were more likely to witness hostility (AOR = 1.87, 95% CI = 1.48–2.36, which was associated with greater odds of problematic drinking (AOR = 1.53; 95% CI = 1

  9. About Women on Campus, 1996.

    Science.gov (United States)

    Sandler, Bernice Resnick, Ed.

    1996-01-01

    This quarterly newsletter provides information about the programs, issues, and concerns of women students, faculty, and administrators in higher education. Each of these four issues (comprising 1 year's worth) presents brief summaries of news items or reports in regularly appearing sections covering campus news, the workplace, sexual harassment,…

  10. About Women on Campus, 1998.

    Science.gov (United States)

    Sandler, Bernice Resnick, Ed.

    1998-01-01

    This quarterly newsletter provides information about the programs, issues, and concerns of women students, faculty, and administrators in higher education. Each of these four issues (comprising a single year) presents brief summaries of new items or reports in regularly appearing sections covering campus news, the workplace, sexual harassment,…

  11. On-campus or online: examining self-regulation and cognitive transfer skills in different learning settings

    Directory of Open Access Journals (Sweden)

    Miri Barak

    2016-11-01

    Full Text Available Abstract This study was set to identify self-regulation skills required for online learning and to characterize cognitive transfer of on-campus and online students. The study included two groups of undergraduate students who studied the same course, but in different settings: online and on-campus. Data collected via an online survey and semi-structured interviews indicated that cognitive strategies and regulation of cognition are significant for successful online learning. Findings also indicated that the online students were more aware of mastery learning and information processing strategies than the on-campus peers. The online students specified the importance of planning, controlling, and evaluation skills for meaningful learning; whereas the on-campus students asserted lack of self-discipline and limited communication skills as barriers for distance learning. Near- and far-transfer components were identified, showing a significant positive correlation with self-regulation skills for both groups of learners.

  12. Style of Life and Student Personnel Policy in College Residence Halls

    Science.gov (United States)

    White, Julie E.

    1969-01-01

    Doctoral dissertation, Dimensions of Conformity and Evasion in Residence Halls for University Women: A Sociological Analysis of Normative Behavior in a Large-Scale Social Organization, 1962, University of Illinois, Urbana.

  13. Sex Roles on Campus: Does Professor Charles Really Get His Angels?

    Science.gov (United States)

    Rochelle, Larry

    1980-01-01

    Reveals factors which foster sexual relationships between male professors and female students. Considers the journals commonly read by males and females and their impact on sexual attitudes. Discusses the issues of miscommunication, sexual harassment, and students' perceptions of sex roles on campus. Suggests ways of dealing with sexual…

  14. Sports and Community on Campus: Constructing a Sports Experience that Matters

    Science.gov (United States)

    Warner, Stacy; Dixon, Marlene A.

    2013-01-01

    Student affairs personnel are often charged with the task of creating a sense of community on campuses. Sports is among the many activities that historically have been used to meet this need for community among students. Yet, how and when a sense of community is created within a sports context has not been appropriately addressed in literature.…

  15. Effective Use of Distance Education Materials for On-Campus Learning.

    Science.gov (United States)

    Roberts, David Woollcombe

    1998-01-01

    This study explores the use of distance study materials for resource-based learning in on-campus education. Describes use of the Jevons/Northcott typology for investigating the pedagogical use of distance learning materials, and discusses results of classroom observation, student diaries, lecturer interviews, and student questionnaires.…

  16. State Legislative Developments on Campus Sexual Violence: Issues in the Context of Safety

    Science.gov (United States)

    Morse, Andrew; Sponsler, Brian A.; Fulton, Mary

    2015-01-01

    NASPA--Student Affairs Administrators in Higher Education and Education Commission of the States (ECS) have partnered to address legislative developments and offer considerations for leaders in higher education and policy on two top-level safety issues facing the higher education community: campus sexual violence and guns on campus. The first in a…

  17. Navigating Conflicts Related to Religious and Non-Religious Identity on Campus

    Science.gov (United States)

    Patel, Eboo; Montero, Janina; Love, Cindi; Giess, Mary Ellen

    2016-01-01

    Matters of interreligious engagement and worldview orientation are becoming more salient on campuses across the country. All-comers policies, conflicts about the Middle East, and intersections of spirituality with other aspects of identity present challenges for professionals working with students on college campuses. This article will discuss…

  18. Ideology, Utopia and Islam on Campus: How to Free Speech a Little from Its Own Terrors

    Science.gov (United States)

    Scott-Baumann, Alison

    2017-01-01

    A dominant narrative on many British campuses is "Prevent," which is part of the government's counter-terror policy, an ideology based on fear. Muslims, in particular, are considered to be at risk of radicalisation on campus, and being under suspicion makes them self-censor. Additionally, the no-platforming student lobby creates a…

  19. "That's so Gay": Heterosexual Male Undergraduates and the Perpetuation of Sexual Orientation Microagressions on Campus

    Science.gov (United States)

    Woodford, Michael R.; Howell, Michael L.; Kulick, Alex; Silverschanz, Perry

    2013-01-01

    "That's so gay," a popular expression on campuses, is a sexual orientation microaggression that can contribute to a hostile environment for lesbian, gay, and bisexual (LGB) students. Using data from a campus climate survey conducted at a large urban university, we investigated use of the phrase among heterosexual male undergraduates who…

  20. Sleep quality and some factors affecting sleep quality in the students living in the residence hall of a university

    Directory of Open Access Journals (Sweden)

    Ozge Yavuz Sari

    2015-04-01

    Full Text Available AIM: Sleep disorders are remarkable public health problems as they adversely affect physical, mental and social health and may cause accidents and decline in academic performance and labor productivity. Aim of the study is assessing sleep quality and determining some factors affecting sleep quality in the students living in the residence hall of a university. METHOD: It is a cross sectional study conducted with 277 students, 180 of whom are female. Data were collected via a questionnaire including Pittsburgh Sleep Quality Index (PSQI, Epworth Sleepiness Scale (ESS and socio-demographic characteristics query. RESULTS: According to PSQI, 41.1% of students have bad sleep quality. Sleep quality of male students and students who are overweight/obese or living in more crowded rooms in the hall of residence is worse than other students and #8217;. Prevalence of bad sleep quality is higher in medication users, participants thinking that they have problems in sleeping or falling asleep and had stressful experience in the last month. The differences between groups were statistically significant. In logistic regression analyzes, using medication (OR=2.54, having problems in sleep (OR=12.75, having problems in falling asleep (OR=8.83 and bad experiences in the last month (OR=2.66 have effects on sleep quality. CONCLUSIONS: Interventions about sleep disorders are important due to their preventable characteristics. Developing healthy life habits, improving physical conditions and coping with stress will be effective on preventing and treating sleep disorders. [TAF Prev Med Bull 2015; 14(2.000: 93-100

  1. Residence Hall Student Satisfaction with Interim Alcohol Policy. Office for Student Affairs Research Bulletin; v15 n4 Jul74.

    Science.gov (United States)

    Seabourg, Deborah; And Others

    At the beginning of the 1973-74 academic year alcohol usage was officially permitted for the first time in residence halls at the Twin Cities Campus of the University of Minnesota. To determine residents' perceptions of the effects of the change in drinking policy, interviews were conducted with 49 current dormitory residents, who had also lived…

  2. Copyright for Movie Night: Film Screenings on Campus

    Directory of Open Access Journals (Sweden)

    Michaela D. Willi Hooper

    2018-02-01

    Full Text Available I undertook this paper so that I, along with other librarians and educators, could better understand how to comply with copyright law, conserve university resources, and streamline services to students regarding the procurement of public performance rights (PPR for films and other audiovisual resources. Student groups frequently screen films on campuses, and accepted legal interpretations of sections 101 and 106 of the 1976 Copyright Act indicate that a specific license should be sought for any public performance of a copyrighted audiovisual work. My review of PPR information on the public websites of the 38 members of the ORBIS-Cascade Alliance (an academic library consortium in the Northwest points to the potential for greater collaboration with student affairs professionals and other campus departments to provide more accurate and complete information about PPR and library audiovisual resources (e.g., DVDs or streaming media that have PPR attached. Campus-focused resources about PPR should include information about fair use, educational exemptions, public domain, open licenses, and library-licensed content that comes with PPR. The academic library community could undertake a project to enhance the accessibility of accurate and supportive PPR information to student groups by creating tools or best practices. This area is ripe for more current research.

  3. An exploratory cluster randomised trial of a university halls of residence based social norms marketing campaign to reduce alcohol consumption among 1st year students.

    Science.gov (United States)

    Moore, Graham F; Williams, Annie; Moore, Laurence; Murphy, Simon

    2013-04-18

    This exploratory trial examines the feasibility of implementing a social norms marketing campaign to reduce student drinking in universities in Wales, and evaluating it using cluster randomised trial methodology. Fifty residence halls in 4 universities in Wales were randomly assigned to intervention or control arms. Web and paper surveys were distributed to students within these halls (n = 3800), assessing exposure/contamination, recall of and evaluative responses to intervention messages, perceived drinking norms and personal drinking behaviour. Measures included the Drinking Norms Rating Form, the Daily Drinking Questionnaire and AUDIT-C. A response rate of 15% (n = 554) was achieved, varying substantially between sites. Intervention posters were seen by 80% and 43% of students in intervention and control halls respectively, with most remaining materials seen by a minority in both groups. Intervention messages were rated as credible and relevant by little more than half of students, though fewer felt they would influence their behaviour, with lighter drinkers more likely to perceive messages as credible. No differences in perceived norms were observed between intervention and control groups. Students reporting having seen intervention materials reported lower descriptive and injunctive norms than those who did not. Attention is needed to enhancing exposure, credibility and perceived relevance of intervention messages, particularly among heavier drinkers, before definitive evaluation can be recommended. A definitive evaluation would need to consider how it would achieve sufficient response rates, whilst hall-level cluster randomisation appears subject to a significant degree of contamination. ISRCTN: ISRCTN48556384.

  4. Measuring Sexual Violence on Campus: Climate Surveys and Vulnerable Groups

    Science.gov (United States)

    de Heer, Brooke; Jones, Lynn

    2017-01-01

    Since the 2014 "Not Alone" report on campus sexual assault, the use of climate surveys to measure sexual violence on campuses across the United States has increased considerably. The current study utilizes a quasi meta-analysis approach to examine the utility of general campus climate surveys, which include a measure of sexual violence,…

  5. Hall A

    Data.gov (United States)

    Federal Laboratory Consortium — The instrumentation in Hall A at the Thomas Jefferson National Accelerator Facility was designed to study electroand photo-induced reactions at very high luminosity...

  6. Hall C

    Data.gov (United States)

    Federal Laboratory Consortium — Hall C's initial complement of equipment (shown in the figure), includes two general-purpose magnetic spectrometers. The High Momentum Spectrometer (HMS) has a large...

  7. The Ripple Effect of Virginia Tech: Assessing the Nationwide Impact on Campus Safety and Security Policy and Practice

    Science.gov (United States)

    Rasmussen, Chris; Johnson, Gina

    2008-01-01

    This report is the result of a nationwide survey conducted in March 2008 of student life officers and campus safety directors to assess the impact of the April 2007 shootings at Virginia Tech on campus safety and security policy and practice. Discussion areas include: (1) Student Privacy vs. Need-to-Know; (2) Prevention, Mitigation and Recovery;…

  8. Hall Sweet Home

    Science.gov (United States)

    Oguntoyinbo, Lekan

    2011-01-01

    Many urban and commuter universities have their sights set on students who are unlikely to connect with the college and likely to fail unless the right strategies are put in place to help them graduate. In efforts to improve retention rates, commuter colleges are looking to an unusual suspect: residence halls. The author discusses how these…

  9. Drawing the Line: Sexual Harassment on Campus

    Science.gov (United States)

    Hill, Catherine; Silva, Elena

    2005-01-01

    This book presents a look at the "big picture." Is sexual harassment common? What kinds of behaviors are taking place? Who is being harassed, and who is doing the harassing? For students who admit to harassing others, why do they do it? How does sexual harassment affect students' educational experience? What do students think should be done about…

  10. Gay Rights on Campus, circa 2011

    Science.gov (United States)

    Cramer, Elizabeth P.; Ford, Charles H.

    2011-01-01

    The environment for lesbian, gay, bisexual, and transgender (LGBT) students, staff, and faculty on college campuses has certainly improved over the last generation, but recent dramatic episodes confirm the continuing need for vigilance and reform. Students remain the constituency most vulnerable to the effects of entrenched bigotry: the harassment…

  11. The Witnesses Walk Your Halls: The School Counselor and Student Victims of Domestic Violence.

    Science.gov (United States)

    Refvem, Joanna

    More than three million children witness domestic violence each year. School counselors need to understand the dynamics of domestic violence, learn the most effective assessments of violence in the lives of their students, and be familiar with the interventions that can be implemented. External stresses on the family do not appear to influence the…

  12. On Campus With Women, Number 31.

    Science.gov (United States)

    Association of American Colleges, Washington, DC. Project on the Status and Education of Women.

    News concerning women students and staff at colleges and universities, equity in education, and nontraditional careers for women is presented. Specific topics include: sexual harassment litigation; surveys concerning sexual harassment within the university and in the federal workplace; a reverse discrimination case in which a white female…

  13. Institutionalizing Political and Civic Engagement on Campus

    Science.gov (United States)

    Hoffman, Adam H.

    2015-01-01

    In this quasi-experimental design, I examine the impact of a political engagement program on students, looking at traditional measures of internal efficacy, as well as other areas of political engagement including levels of political knowledge, the development of political skills, and interest in media coverage of politics.

  14. Social Class on Campus: Theories and Manifestations

    Science.gov (United States)

    Barratt, Will

    2011-01-01

    This is at once a playful text with a serious purpose: to provide the reader with the theoretical lenses to analyze the dynamics of social class. It will appeal to students, and indeed anyone interested in how class mediates relationships in higher education, both because of its engaging tone, and because it uses the college campus as a microcosm…

  15. Racialized Aggressions and Social Media on Campus

    Science.gov (United States)

    Gin, Kevin J.; Martínez-Alemán, Ana M.; Rowan-Kenyon, Heather T.; Hottell, Derek

    2017-01-01

    Using a phenomenological approach, rooted in critical theory's desire to challenge systemic structures of inequality, we explored the impact of racialized hate encountered on social media by students of color at a predominately White institution. The encounters of racialized hostility manifested as anti-Black sentiments and produced racial battle…

  16. Laurance David Hall.

    Science.gov (United States)

    Coxon, Bruce

    2011-01-01

    An account is given of the life, scientific contributions, and passing of Laurance David Hall (1938-2009), including his early history and education at the University of Bristol, UK, and the synthesis and NMR spectroscopy of carbohydrates and other natural products during ∼20 years of research and teaching at the University of British Columbia in Vancouver, Canada. Lists of graduate students, post-doctoral fellows, and sabbatical visitors are provided for this period. Following a generous endowment by Dr. Herchel Smith, Professor Hall built a new Department of Medicinal Chemistry at Cambridge University, UK, and greatly expanded his researches into the technology and applications of magnetic resonance imaging (MRI) and zero quantum NMR. MRI technology was applied both to medical problems such as the characterization of cartilage degeneration in knee joints, the measurement of ventricular function, lipid localization in animal models of atherosclerosis, paramagnetic metal complexes of polysaccharides as contrast agents, and studies of many other anatomical features, but also to several aspects of materials analysis, including food analyses, process control, and the elucidation of such physical phenomena as the flow of liquids through porous media, defects in concrete, and the visualization of fungal damage to wood. Professor Hall's many publications, patents, lectures, and honors and awards are described, and also his successful effort to keep the Asilomar facility in Pacific Grove, California as the alternating venue for the annual Experimental NMR Conference. Two memorial services for Professor Hall are remembered. Copyright © 2011 Elsevier Inc. All rights reserved.

  17. Plant biology: From on-campus to on-line development and implementation

    Science.gov (United States)

    Bradley, Lucy K.

    The lecture content of the Plant Biology class for non-majors was transformed from a traditional on-campus lecture to an asynchronous website that could be used both as a stand-alone course and as an adjunct to the on campus course sections. In addition, an interactive, on-line website with home laboratory experiments was developed and implemented by the Plant Biology Department in collaboration with design specialists from the Information Technology and Instructional Support Department of the Arizona State University. The 259-page lecture website included 134 interactive animations, as well as 11 videos. The lab website included 176 pages, with 187 graphics and 36 separate animations. Convenience was identified by most students as the key benefit of taking the course on-line. Website construction was rated highly by all of the students; however, website audio was problematic for 50% of them; video, for 71%. Students, staff, and faculty all agreed that to benefit fully from the website, adequate hardware, software, and internet connection speed were vital. Challenges with the web-based lab were either technological (inadequate equipment or skills), logistical (dissatisfaction with having to pick up home lab kits from campus), or motivational (student survey responses added to the growing literature that suggests that mature, focused, self-motivated students benefit more from distance learning).

  18. On Campus with Women, Number 27, Summer 1980.

    Science.gov (United States)

    Association of American Colleges, Washington, DC.

    A newsletter on issues pertaining to women's rights on campuses and in employment is presented. Developments and issues include the following: initiation of intercollegiate athletic championships for women in nine sports; a charge of unequal pay for women coaches; university cases of alleged sex discrimination in athletic programs; reference to…

  19. The Vietnam War on Campus: Other Voices, More Distant Drums.

    Science.gov (United States)

    Gilbert, Marc Jason, Ed.

    The essays in this collection represent recent scholarship on campus unrest in the 1960s and 1970s. They provide a variety of case studies of the 1960s movements and events beyond the more highly publicized events, and they offer new insights into the antiwar movement. The essays are: (1) "Pro-War and Anti-Draft: Young Americans for Freedom…

  20. The Impact of a Health Campaign on Hand Hygiene and Upper Respiratory Illness among College Students Living in Residence Halls.

    Science.gov (United States)

    White, Cindy; Kolble, Robin; Carlson, Rebecca; Lipson, Natasha

    2005-01-01

    Hand hygiene is a key element in preventing the transmission of cold and flu viruses. The authors conducted an experimental-control design study in 4 campus residence halls to determine whether a message campaign about hand hygiene and the availability of gel hand sanitizer could decrease cold and flu illness and school and work absenteeism. Their…

  1. OnCampus: a mobile platform towards a smart campus.

    Science.gov (United States)

    Dong, Xin; Kong, Xiangjie; Zhang, Fulin; Chen, Zhen; Kang, Jialiang

    2016-01-01

    An increasing number of researchers and practitioners are working to develop smart cities. Considerable attention has been paid to the college campus as it is an important component of smart cities. Consequently, the question of how to construct a smart campus has become a topical one. Here, we propose a scheme that can facilitate the construction of a smart and friendly campus. We primarily focus on three aspects of smart campuses. These are: the formation of social circles based on interests mining, the provision of educational guidance based on emotion analysis of information posted on a platform, and development of a secondary trading platform aimed at optimizing the allocation of campus resources. Based on these objectives, we designed and implemented a mobile platform called OnCampus as the first step towards the development of a smart campus that has been introduced in some colleges. We found that OnCampus could successfully accomplish the three above mentioned functions of a smart campus.

  2. Political Bias on Campus: Understanding the Student Experience

    Science.gov (United States)

    Linvill, Darren L.; Havice, Pamela A.

    2011-01-01

    The role ideology plays in the university classroom has been debated since the publication of Buckley's "God and Man at Yale" (1951). The "Chronicle of Higher Education's" Special Report (2004) found that more than half of United States citizens polled felt that U.S. colleges and universities improperly introduce a liberal…

  3. Methylphenidate use among students living in junior on-campus ...

    African Journals Online (AJOL)

    PM Van Zyl

    2016-10-19

    Oct 19, 2016 ... treatment of ADHD in children as well as adults, with remarkable effects on ADHD symptoms in classroom settings over the short term,5 but long-term effects are not well known.6 In addition to being effective for adult ADHD, .... speed; verbal learning and memory; attention and vigilance; and reasoning and ...

  4. Experimental halls workshop summary

    International Nuclear Information System (INIS)

    Thorndike, A.

    1976-01-01

    A brief discussion is given of: (1) pros and cons of open areas as compared with enclosed halls; (2) experimental hall needs of ep, anti p p, and other options; (3) hall for the lepton detector; and, (4) hall for the hadron spectrometer

  5. Experimental halls workshop summary

    International Nuclear Information System (INIS)

    Thorndike, A.

    1976-01-01

    On May 26 and 27, 1976, approximately 50 people met for an informal workshop on plans for experimental halls for ISABELLE. Plans as they exist in the May 1976 version of the ISABELLE proposal were presented. Discussions were held on the following four general topics by separate working groups: (1) pros and cons of open areas as compared with enclosed halls; (2) experimental hall needs of ep, anti pp, and other options; (3) hall for the lepton detector; and (4) hall for the hadron spectrometer. The planning for experimental halls at PEP, the hall for the lepton detector, the hadron spectrometer, and open areas are discussed

  6. Comparing On-Campus and Distance Education assessment in the form of Project Organized Problem Based Learning (POPBL)

    DEFF Research Database (Denmark)

    Helbo, Jan; Borch, Ole

    2006-01-01

    This paper describes the first experiences in on-line assessment in the POPBL distance education: Master of Industrial Information technology (MII) at Aalborg University, Denmark (AAU). The accomplished assessment of some projects and some courses has been changed from a normal on-campus seminar...... activity to an on-line event. The modifications in roles for teacher, censor and student are reported and some recommendations and unsolved problems are identified....

  7. Experimental halls workshop summary

    International Nuclear Information System (INIS)

    Thorndike, A.

    1976-01-01

    At the experimental halls workshop, discussions were held on: (1) open areas as compared with enclosed halls; (2) the needs of ep, anti pp, and other options; (3) the hall for the lepton detector; and (4) the hall for the hadron spectrometer. The value of different possibilities for the future experimental program was explored. A number of suggestions emerged which will be used as the design of the experimental halls progresses

  8. Engagement in Digital Lecture Halls: A Study of Student Course Engagement and Mobile Device Use during Lecture

    Science.gov (United States)

    Witecki, Gwendolyn; Nonnecke, Blair

    2015-01-01

    Universities have experienced increases in technology ownership and usage amongst students entering undergraduate programs. Almost all students report owning a mobile phone and many students view laptops and tablets as educational tools, though they also report using them for nonacademic activities during lectures. We explored the relationship…

  9. Engagement in Digital Lecture Halls: A Study of Student Course Engagement and Mobile Device use During Lecture

    Directory of Open Access Journals (Sweden)

    Gwendolyn Witecki

    2015-01-01

    Full Text Available Universities have experienced increases in technology ownership and usage amongst students entering undergraduate programs. Almost all students report owning a mobile phone and many students view laptops and tablets as educational tools, though they also report using them for non-academic activities during lectures. We explored the relationship between student course engagement and the use of smartphones, laptops, cell phones, and tablets during lecture. Undergraduate students responded to an online survey asking about both course engagement and mobile device habits. Results show that smartphone use was most strongly related to lowered course engagement and while laptop use was related to lowered engagement, it was to a lesser extent. In contrast, overall engagement of students using tablets or cell phones was not significantly different than those who did not.

  10. Grief and Solidarity Reactions 1 Week After an On-Campus Shooting.

    Science.gov (United States)

    Wayment, Heidi A; Silver, Roxane Cohen

    2018-03-01

    The impact of interpersonal violence extends beyond the victims and perpetrator(s). The purpose of this research was threefold: (a) to identify whether college students' very early reactions to an on-campus shooting were associated with well-known predictors of distress, (b) to examine whether grief and distress reactions were distinguishable in the early days following a shooting, and (c) to investigate whether a compassionate self-identity was uniquely associated with grief but not distress. Beginning just 3 days after an early morning shooting that killed one student and injured three others, university students ( N = 408) completed an online questionnaire. Grief, but not distress, was associated with a sense of solidarity with other students and a compassionate self-identity. General distress was associated with prior mental health difficulties and exposure to the shooting. Acute stress was positively associated with being female, having prior mental health difficulties, media exposure, perceived similarity to victims, less victim blame, social support, and social strain. Results suggest that grief reactions that arise in the early days following a collective loss may serve as important psychosocial resources in coping with interpersonal violence.

  11. Cryogenic microsize Hall sensors

    International Nuclear Information System (INIS)

    Kvitkovic, J.; Polak, M.

    1993-01-01

    Hall sensors have a variety of applications in magnetic field measurements. The active area of the Hall sensor does not play an important role in measuring of homogeneous magnetic field. Actually Hall sensors are widely used to measure profiles of magnetic fields produced by magnetization currents in samples of HTC superconductors, as well as of LTC ones. Similar techniques are used to measure magnetization of both HTC and LTC superconductors. In these cases Hall sensor operates in highly inhomogeneous magnetic fields. Because of that, Hall sensors with very small active area are required. We developed and tested Hall sensors with active area 100 μm x 100 μm - type M and 50 μm x 50 μm - type V. Here we report on the most imporant parameters of these units, as well as on their properties as differential magnetometer. (orig.)

  12. Guns on Campus: The Architecture and Momentum of State Policy Action

    Science.gov (United States)

    Morse, Andrew; Sisneros, Lauren; Perez, Zeke; Sponsler, Brian A.

    2016-01-01

    "Guns on Campus: The Architecture and Momentum of State Policy Action" offers a detailed summary of state legislative action and higher education system policy decisions that have occurred in two specific categories: (1) States that have permitted or are seeking to permit guns on campus; and (2) States that have prohibited or are seeking…

  13. Skyrmions and Hall viscosity

    Science.gov (United States)

    Kim, Bom Soo

    2018-05-01

    We discuss the contribution of magnetic Skyrmions to the Hall viscosity and propose a simple way to identify it in experiments. The topological Skyrmion charge density has a distinct signature in the electric Hall conductivity that is identified in existing experimental data. In an electrically neutral system, the Skyrmion charge density is directly related to the thermal Hall conductivity. These results are direct consequences of the field theory Ward identities, which relate various physical quantities based on symmetries and have been previously applied to quantum Hall systems.

  14. Green design application on campus to enhance student’s quality of life

    Science.gov (United States)

    Tamiami, H.; Khaira, F.; Fachrudin, A.

    2018-02-01

    Green design becomes an important thing to applied in the building. Green building will provide comfortability and enhance Quality of Life (QoL) for the users. The purpose of this research is to analyze how green design application on campus to enhance student’s QoL. This research conducted in three campuses which located in North Sumatera Province, namely Universitas Sumatera Utara (USU), Universitas Negeri Medan (Unimed) and Universitas Medan Area (UMA) which have a lot of vegetation, open space, and multi-mass buildings. This research compared the green design application to QoL from three universities. Green design in this research that become independent variables focus on the energy efficiency and conservation (EEC), indoor health and comfort (IHC) and building environment management (BEM) with dependent variable is QoL. This research uses quantitative methods with questionnaire survey techniques. The population is students from the three universities with the sample of each University is 50 samples. The analysis uses multiple regression analysis. The results show that green design application may enhance QoL of students. The campus should have a good green design application to enhance QoL of students and give them comfortability.

  15. Sexting and Student Discipline

    Science.gov (United States)

    O'Donovan, Eamonn

    2010-01-01

    Cell phones are ubiquitous on campus, and the anytime anywhere nature of teenage communications means that students see no separation between life inside and outside of school, at least when it comes to activities such as texting. Allowing cell phones on campus will have students in possession of cell phones with sexually oriented messages,…

  16. The relationship between students’ perceptions of the University of Pretoria’s on-campus green spaces and attention restoration

    Directory of Open Access Journals (Sweden)

    Ruth M Liprini

    2017-11-01

    Full Text Available Previous research has suggested that natural green areas provide several psychological benefits to individuals. One such benefit is the restoration of attention capacities, an advantage that is of particular importance to university students. The present study, therefore, aimed to determine where students spend their free time on campus at the University of Pretoria, South Africa, how they perceive their on-campus green spaces and the extent to which they found these spaces restorative. Participants responded to a three-part questionnaire, investigating demographic characteristics, green space usage, and the Perceived Restorativeness Scale (PRS. Statistical analyses were conducted to determine which of the green spaces contributed most significantly to overall PRS scores. All green areas made significant contributions, but the campus’s botanical garden was the greatest contributor to PRS. The findings of this study serve to encourage tertiary institutions to protect their green spaces, as the psychological well-being and attention restoration of students are affected by it.

  17. Plant Operations. OSHA on Campus: Campus Safety Officers Discuss Problems and Potentials

    Science.gov (United States)

    Kuchta, Joseph F.; And Others

    1973-01-01

    The Occupation Safety and Health Act (OSHA) has presented campus safety officers with new problems, but it is also offering them new potentials, which were explored at the recent national conference on Campus Security. (Editor)

  18. Intercultural Development: Study Abroad vs. On-Campus Study

    Science.gov (United States)

    Anderson, Phillip H.; Lawton, Leigh

    2011-01-01

    As international travel has become more commonplace and as the economies of the world have become more interdependent, both students and faculties are recognizing the importance of increasing students' ability to function effectively in a global community. Study abroad programs are seen by many as an effective means to provide students with the…

  19. The Courage To Care: Addressing Sexual Minority Issues on Campus.

    Science.gov (United States)

    Ottenritter, Nan

    1998-01-01

    Sexual minority students face issues similar to those of ethnic and racial minority students. This article provides a framework for assessing the community college's inclusion of sexual minority students: lesbians, gays, bisexual, and transgender (LGBT) individuals. The first section of the article assesses community colleges in terms of sexual…

  20. Commemorative Symposium on the Hall Effect and its Applications

    CERN Document Server

    Westgate, C

    1980-01-01

    In 1879, while a graduate student under Henry Rowland at the Physics Department of The Johns Hopkins University, Edwin Herbert Hall discovered what is now universally known as the Hall effect. A symposium was held at The Johns Hopkins University on November 13, 1979 to commemorate the lOOth anniversary of the discovery. Over 170 participants attended the symposium which included eleven in­ vited lectures and three speeches during the luncheon. During the past one hundred years, we have witnessed ever ex­ panding activities in the field of the Hall effect. The Hall effect is now an indispensable tool in the studies of many branches of condensed matter physics, especially in metals, semiconductors, and magnetic solids. Various components (over 200 million!) that utilize the Hall effect have been successfully incorporated into such devices as keyboards, automobile ignitions, gaussmeters, and satellites. This volume attempts to capture the important aspects of the Hall effect and its applications. It includes t...

  1. Halls Lake 1990

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Salt marsh habitats along the shoreline of Halls Lake are threatened by wave erosion, but the reconstruction of barrier islands to reduce this erosion will modify or...

  2. Effects of a new parallel primary healthcare centre and on-campus training programme on history taking, physical examination skills and medical students’ preparedness: a prospective comparative study in Taiwan

    Science.gov (United States)

    Yang, Ying-Ying; Wang, Shuu-Jiun; Yang, Ling-Yu; Lirng, Jiing-Feng; Huang, Chia-Chang; Liang, Jen-Feng; Lee, Fa-Yauh; Hwang, Shinn-Jang; Huang, Chin-Chou; Kirby, Ralph

    2017-01-01

    Objectives The primary healthcarecentre (PHCC) is the first place that medical students experience patient contact. Usually, medical students are frustrated by a lack of proper skills training for on-campus history taking (HT), physical examination (PE) and self-directed learning (SDL) to prepare for their PHCC and inhospital patient contact. For pre-clerks, this study aims to compare the effectiveness of PHCC training and PHCC training in combination with on-campus HT and PE training modules (PHCC+on-campus) on their clerkship preparedness. Design This comparative study utilised prospective, consecutive, end of pre-clerkship group objective structured clinical examination (GOSCE), beginning of clerkship OSCE and self-administered Preparation for Hospital Practice Questionnaire (PHPQ). Setting/participants 128 pre-clinical clerk volunteers (64 each year) receiving PHCC training (7 week PHCCtraining in addition to 7 week assignment based group learning, academic year 2014, controls) and PHCC training in combination with on-campus module training (academic year 2015, 7 week PHCCtraining in addition to 7 week on-campus sessions) were sequentially assessed before the module (week 1), at the end of the module (week 14) and at the beginning of clerkship (week 25). Results For overall HT and PE skills, both PHCC and PHCC+on-campus module trained pre-clerks performed better on OSCE than GOSCE. Additionally, the improvement was accompanied by higher self-reported PHPQ scores in ‘confidence/coping’ and ‘SDL’ domains. At the end of the pre-clerkship and the beginning of the clerkship stages, the degree of improvement in preparedness in ‘confidence/coping’ and ‘SDL’ domains was higher for those in the PHCC+on-campus group than for those in the PHCC group. Among the PHCC+on-campus module participants, a positive association was observed between high mean PHPQ-SDL scores and high OSCE scores. Conclusions Our study suggests that the PHCC+on-campus module

  3. The quantum hall effect

    International Nuclear Information System (INIS)

    El-Arabi, N. M.

    1993-01-01

    Transport phenomena in two dimensional semiconductors have revealed unusual properties. In this thesis these systems are considered and discussed. The theories explain the Integral Quantum Hall Effect (IQHE) and the Fractional Quantum Hall Effect (FQHE). The thesis is composed of five chapters. The first and the second chapters lay down the theory of the IQHE, the third and fourth consider the theory of the FQHE. Chapter five deals with the statistics of particles in two dimension. (author). Refs

  4. Hall viscosity of hierarchical quantum Hall states

    Science.gov (United States)

    Fremling, M.; Hansson, T. H.; Suorsa, J.

    2014-03-01

    Using methods based on conformal field theory, we construct model wave functions on a torus with arbitrary flat metric for all chiral states in the abelian quantum Hall hierarchy. These functions have no variational parameters, and they transform under the modular group in the same way as the multicomponent generalizations of the Laughlin wave functions. Assuming the absence of Berry phases upon adiabatic variations of the modular parameter τ, we calculate the quantum Hall viscosity and find it to be in agreement with the formula, given by Read, which relates the viscosity to the average orbital spin of the electrons. For the filling factor ν =2/5 Jain state, which is at the second level in the hierarchy, we compare our model wave function with the numerically obtained ground state of the Coulomb interaction Hamiltonian in the lowest Landau level, and find very good agreement in a large region of the complex τ plane. For the same example, we also numerically compute the Hall viscosity and find good agreement with the analytical result for both the model wave function and the numerically obtained Coulomb wave function. We argue that this supports the notion of a generalized plasma analogy that would ensure that wave functions obtained using the conformal field theory methods do not acquire Berry phases upon adiabatic evolution.

  5. Gender Variance on Campus: A Critical Analysis of Transgender Voices

    Science.gov (United States)

    Mintz, Lee M.

    2011-01-01

    Transgender college students face discrimination, harassment, and oppression on college and university campuses; consequently leading to limited academic and social success. Current literature is focused on describing the experiences of transgender students and the practical implications associated with attempting to meet their needs (Beemyn,…

  6. Mobile Business Retailing: Driving Experiential Learning on Campus

    Science.gov (United States)

    Fischbach, Sarah; Guerrero, Veronica

    2018-01-01

    Engaging students in the classroom is a struggle all faculty face especially in the age of modern technology. This article proposes a novel approach to engage and motivate students through the mobile business "on wheels" marketing concept. The growth in mobile business retailing (e.g., food trucks, mobile dog groomers, etc.) is an…

  7. Smoking restrictions on campus: changes and challenges at three Canadian universities, 1970-2010.

    Science.gov (United States)

    Procter-Scherdtel, Amy; Collins, Damian

    2013-01-01

    This article examines the restriction of smoking on university campuses in the Canadian context. Indoor smoking on campus is now completely prohibited by law, and universities are increasingly moving to restrict, or prohibit, outdoor smoking on their grounds. The research focuses on three case studies to identify changes in spatial restrictions on campus smoking over the last four decades (1970-2010), and to determine the challenges involved in establishing bans in outdoor areas of campus. The three universities were selected for their different approaches to the issue of outdoor smoking. Data collection involved semi-structured interviews with 36 key informants, conducted from September 2010 to January 2011, supplemented by documentary information. Interview data were analysed thematically. Protection against environmental tobacco smoke (ETS) on campus proceeded incrementally, via policy-making at the provincial, municipal and institutional levels. Historically, institutional bans on indoor smoking were particularly significant, but their health benefits could be limited by the presence of private property on campus. Universities continue to initiate smoking restrictions today, with respect to outdoor bans. However, respondents reported myriad challenges in developing, implementing and maintaining such bans. Five principal concerns were articulated: the need for ongoing policy communication; management of community relations as smokers are displaced from campus; enforcement to ensure that the policy has practical effect; safety concerns; and difficulties relating to campus layout. Because challenges are diverse and contextual, effective protection against outdoor ETS on campus is likely to require an ongoing commitment on the part of administrators. © 2012 Blackwell Publishing Ltd.

  8. The quantized Hall effect

    International Nuclear Information System (INIS)

    Klitzing von, K.

    1989-01-01

    The quantized Hall effect is theoretically explained in detail as are its basic properties. The explanation is completed with the pertinent mathematical relations and illustrative figures. Experimental data are critically assessed obtained by quantum transport measurement in a magnetic field on two-dimensional systems. The results are reported for a MOSFET silicon transistor and for GaAs-Al x Ga 1-x As heterostructures. The application is discussed of the quantized Hall effect in determining the fine structure constant or in implementing the resistance standard. (M.D.). 27 figs., 57 refs

  9. Intrinsic superspin Hall current

    Science.gov (United States)

    Linder, Jacob; Amundsen, Morten; Risinggârd, Vetle

    2017-09-01

    We discover an intrinsic superspin Hall current: an injected charge supercurrent in a Josephson junction containing heavy normal metals and a ferromagnet generates a transverse spin supercurrent. There is no accompanying dissipation of energy, in contrast to the conventional spin Hall effect. The physical origin of the effect is an antisymmetric spin density induced among transverse modes ky near the interface of the superconductor arising due to the coexistence of p -wave and conventional s -wave superconducting correlations with a belonging phase mismatch. Our predictions can be tested in hybrid structures including thin heavy metal layers combined with strong ferromagnets and ordinary s -wave superconductors.

  10. Hall effect in hopping regime

    International Nuclear Information System (INIS)

    Avdonin, A.; Skupiński, P.; Grasza, K.

    2016-01-01

    A simple description of the Hall effect in the hopping regime of conductivity in semiconductors is presented. Expressions for the Hall coefficient and Hall mobility are derived by considering averaged equilibrium electron transport in a single triangle of localization sites in a magnetic field. Dependence of the Hall coefficient is analyzed in a wide range of temperature and magnetic field values. Our theoretical result is applied to our experimental data on temperature dependence of Hall effect and Hall mobility in ZnO. - Highlights: • Expressions for Hall coefficient and mobility for hopping conductivity are derived. • Theoretical result is compared with experimental curves measured on ZnO. • Simultaneous action of free and hopping conduction channels is considered. • Non-linearity of hopping Hall coefficient is predicted.

  11. Hall effect in hopping regime

    Energy Technology Data Exchange (ETDEWEB)

    Avdonin, A., E-mail: avdonin@ifpan.edu.pl [Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warszawa (Poland); Skupiński, P. [Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warszawa (Poland); Grasza, K. [Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warszawa (Poland); Institute of Electronic Materials Technology, ul. Wólczyńska 133, 01-919 Warszawa (Poland)

    2016-02-15

    A simple description of the Hall effect in the hopping regime of conductivity in semiconductors is presented. Expressions for the Hall coefficient and Hall mobility are derived by considering averaged equilibrium electron transport in a single triangle of localization sites in a magnetic field. Dependence of the Hall coefficient is analyzed in a wide range of temperature and magnetic field values. Our theoretical result is applied to our experimental data on temperature dependence of Hall effect and Hall mobility in ZnO. - Highlights: • Expressions for Hall coefficient and mobility for hopping conductivity are derived. • Theoretical result is compared with experimental curves measured on ZnO. • Simultaneous action of free and hopping conduction channels is considered. • Non-linearity of hopping Hall coefficient is predicted.

  12. Therapy Dogs on Campus: Recommendations for Counseling Center Outreach

    Science.gov (United States)

    Daltry, Rachel M.; Mehr, Kristin E.

    2015-01-01

    This article describes the design and implementation of a dog therapy outreach program through the counseling center at West Chester University in Pennsylvania. Two main goals were identified for this program: (a) provide stress relief and comfort to students across campus, and (b) increase potential access to counseling services and improve…

  13. Making Our Voices Audible in the Conversation on Campus Safety

    Science.gov (United States)

    Roper, Larry D.

    2011-01-01

    Campus safety and the role of college and university officials relative to safety are important topics on the agendas of political leaders at the state and national levels. Student affairs leaders must consider how to contribute in a meaningful way to these very important conversations. (Contains 1 footnote.)

  14. "Star Wars" on Campus: Scientists Debate the Wisdom of SDI.

    Science.gov (United States)

    Rosenblatt, Jean

    1987-01-01

    President Reagan's Strategic Defense Initiative is opposed by many university scientists, but government officials have no problem placing research contracts. Specific arrangements and personal opinions are cited, and the text of the Star Wars Petition signed by 6,500 faculty and graduate student scientists is included. (MSE)

  15. Human Resources Underutilized: The Plight of Women on Campus!

    Science.gov (United States)

    McGinty, Robert L.

    2010-01-01

    Legal, cultural, and ethical considerations impact decisions of organizations and those of the individuals who aspire to assume their rightful role in them as students enrolled at universities or as aspiring employees in business firms. An ongoing question emerges, however, concerning the barriers and cultural attitudes toward women (and…

  16. Breaking the Silence Surrounding Mental Health on Campus

    Science.gov (United States)

    Roper, Larry D.

    2013-01-01

    Mentally ill students are able to participate in higher education at unprecedented rates. While colleges and universities have been responsive to the therapeutic needs, we have failed to successfully create supportive campus climates. Campus leaders are challenged to demonstrate ethical leadership that breaks the silence and confronts the stigma…

  17. Mobile Learning on Campus: Balancing on the Cutting Edge

    Science.gov (United States)

    Raths, David

    2010-01-01

    As soon as the Illinois Institute of Technology (IIT) announced last May that it would be giving all 400 incoming freshmen Apple iPads, a lively debate broke out online at TUAW.com (The Unofficial Apple Weblog) between people who saw it as a marketing gimmick to attract students and others who believed it was an honest attempt to implement a new…

  18. The Monty Hall Dilemma.

    Science.gov (United States)

    Granberg, Donald; Brown, Thad A.

    1995-01-01

    Examines people's behavior in the Monty Hall Dilemma (MHD), in which a person must make two decisions to win a prize. In a series of five studies, found that people misapprehend probabilities in the MHD. Discusses the MHD's relation to illusion of control, belief perseverance, and the status quo bias. (RJM)

  19. The Isolde experimental hall

    CERN Multimedia

    Laurent Guiraud

    2000-01-01

    General view of the Isotope-Separator On-Line (ISOLDE) hall. ISOLDE is dedicated to the production of a large variety of radioactive ion beams for many different experiments. Rare isotopes can be produced allowing the study of spectra for neutrino beam production.

  20. Anomalous Hall effect

    Czech Academy of Sciences Publication Activity Database

    Nagaosa, N.; Sinova, Jairo; Onoda, S.; MacDonald, A. H.; Ong, N. P.

    2010-01-01

    Roč. 82, č. 2 (2010), s. 1539-1592 ISSN 0034-6861 Institutional research plan: CEZ:AV0Z10100521 Keywords : anomalous Hall effect * spintronics Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 51.695, year: 2010

  1. The Significance of a Building’s Energy Consumption Profiles for the Optimum Sizing of a Combined Heat and Power (CHP System—A Case Study for a Student Residence Hall

    Directory of Open Access Journals (Sweden)

    Khuram Pervez Amber

    2018-06-01

    Full Text Available University buildings, such as student residence halls with year-round consistent energy demands, offer strong opportunities for Combined Heat and Power (CHP systems. The economic and environmental feasibility of a CHP project is strongly linked with its optimum sizing. This study aims to undertake such an assessment for a CHP system for a student residence hall located in London, the United Kingdom (UK. The study also aims to undertake a sensitivity analysis to investigate the effect of different parameters on the project’s economics. Necessary data are collected via interviews with the University’s Energy Manager. Modeling of the CHP system is performed using the London South Bank University (LSBU, London, the UK CHP model. Results demonstrate that optimum sizing of CHP is crucial for achieving higher economic and environmental benefits and strongly depends on the authenticity of the energy consumption data, based on which the CHP is being sized. Use of incorrect energy data could result in an undersized or oversized CHP system, where an oversized system will result in higher negative results compared to an undersized system. Finally, Monto Carlo statistical analysis shows that electricity price is the significant factor that could affect the project’s economics. With an increasing spark gap, the payback period decreases, and vice versa.

  2. The influence of a student's 'home' climate on room temperature and indoor environmental controls use in a modern halls of residence

    OpenAIRE

    Amin, Rucha; Teli, Despoina; James, Patrick; Bourikas, Leonidas

    2016-01-01

    Adaptive comfort theory states that over time people adapt to their normal environment. Therefore, people from different climates are expected to have different thermal preferences and behaviours, which could lead to ‘performance gap’ in buildings with occupants of diverse climate backgrounds. This study investigates the influence of occupants’ thermal history on use of controls and indoor temperature preference in a newly built halls of residence building complex in Southampton, UK, which pr...

  3. Spin Hall effects

    Science.gov (United States)

    Sinova, Jairo; Valenzuela, Sergio O.; Wunderlich, J.; Back, C. H.; Jungwirth, T.

    2015-10-01

    Spin Hall effects are a collection of relativistic spin-orbit coupling phenomena in which electrical currents can generate transverse spin currents and vice versa. Despite being observed only a decade ago, these effects are already ubiquitous within spintronics, as standard spin-current generators and detectors. Here the theoretical and experimental results that have established this subfield of spintronics are reviewed. The focus is on the results that have converged to give us the current understanding of the phenomena, which has evolved from a qualitative to a more quantitative measurement of spin currents and their associated spin accumulation. Within the experimental framework, optical-, transport-, and magnetization-dynamics-based measurements are reviewed and linked to both phenomenological and microscopic theories of the effect. Within the theoretical framework, the basic mechanisms in both the extrinsic and intrinsic regimes are reviewed, which are linked to the mechanisms present in their closely related phenomenon in ferromagnets, the anomalous Hall effect. Also reviewed is the connection to the phenomenological treatment based on spin-diffusion equations applicable to certain regimes, as well as the spin-pumping theory of spin generation used in many measurements of the spin Hall angle. A further connection to the spin-current-generating spin Hall effect to the inverse spin galvanic effect is given, in which an electrical current induces a nonequilibrium spin polarization. This effect often accompanies the spin Hall effect since they share common microscopic origins. Both can exhibit the same symmetries when present in structures comprising ferromagnetic and nonmagnetic layers through their induced current-driven spin torques or induced voltages. Although a short chronological overview of the evolution of the spin Hall effect field and the resolution of some early controversies is given, the main body of this review is structured from a pedagogical

  4. Resources on Campus Governance and Employment Relations, 1967-1977. With Essay, Annotations, and Indexes.

    Science.gov (United States)

    Tice, Terrence N.

    An annotated bibliography containing 1,110 items from 1967 through early 1977 and other relevant resources covers virtually all the significant material on campus collective bargaining and closely related issues regarding campus governance and employment relations. It complements five publications from 1972-76 and indexes both authors and…

  5. Online vs. On-Campus: An Analysis of Course Prices of U.S. Educational Institutions

    Science.gov (United States)

    Wang, Shouhong

    2015-01-01

    Pricing online courses is an important issue for managing online education. This research note reports a statistical analysis of price differences between online courses and on-campus courses at 103 US educational institutions based on the data available on the Internet. The finding indicates that educational institutions set significantly lower…

  6. Sexual Violence and Alcohol and Other Drug Use on Campus. Infofacts/Resources

    Science.gov (United States)

    Higher Education Center for Alcohol and Other Drug Abuse and Violence Prevention, 2008

    2008-01-01

    This "Infofacts/Resources" describes the scope of the problem of sexual assault on campus, perpetrator characteristics and situational circumstances that may make assaults more likely to happen, and the role alcohol and other drugs, including rape-facilitating drugs, play in sexual assault. This publication also provides an overview of sexual…

  7. Paired Hall states

    International Nuclear Information System (INIS)

    Greiter, M.

    1992-01-01

    This dissertation contains a collection of individual articles on various topics. Their significance in the corresponding field as well as connections between them are emphasized in a general and comprehensive introduction. In the first article, the author explores the consequences for macroscopic effective Lagrangians of assuming that the momentum density is proportional to the flow of conserved current. The universal corrections obtained for the macroscopic Lagrangian of a superconductor describe the London Hall effect, and provide a fully consistent derivation of it. In the second article, a heuristic principle is proposed for quantized Hall states: the existence and incompressibility of fractionally quantized Hall states is explained by an argument based on an adiabatic localization of magnetic flux, the process of trading uniform flux for an equal amount of fictitious flux attached to the particles. This principle is exactly implemented in the third article. For a certain class of model Hamiltonians, the author obtains Laughlin's Jastrow type wave functions explicitly from a filled Landau level, by smooth extrapolation in quantum statistics. The generalization of this analysis to the torus geometry shows that theorems restricting the possibilities of quantum statistics on closed surfaces are circumvented in the presence of a magnetic field. In the last article, the existence is proposed of a novel incompressible quantum liquid, a paired Hall state, at a half filled Landau level. This state arises adiabatically from free fermions in zero magnetic field, and reduces to a state previously proposed by Halperin in the limit of tightly bound pairs. It supports unusual excitations, including neutral fermions and charge e/4 anyons with statistical parameter θ = π/8

  8. Teachers’ and Students’ Experiences of Simultaneous Teaching in an International Distance and On-Campus Master’s Programme in Engineering

    Directory of Open Access Journals (Sweden)

    Oleg Popov

    2009-06-01

    Full Text Available Swedish universities frequently offer campus-based education as well as online courses, a system commonly referred to as dual mode. This paper analyses some challenging pedagogical aspects of a master’s programme in engineering developed and delivered simultaneously online and on campus. Course evaluations, questionnaires, and interviews with the programme teachers were the main instruments used in this study. Activity theory was used as a theoretical framework for data collection and analysis. The study evidences the nature of problems experienced by on-campus and distance students as well as conflicts of interest and expectations existing between these two student groups. Teaching simultaneously in two modes demands extra effort from the course teachers, who are aware of the problems related to pedagogical communication needed by both groups. Though teaching in the dual mode offers economic benefits for the department, the simultaneous mode of teaching is experienced as problematical by both groups of students, with distance students appearing to be more disadvantaged in the programme.

  9. Guild Hall retrofit

    Energy Technology Data Exchange (ETDEWEB)

    1984-08-01

    This report demonstrates the economic viability of an exterior rewrap retrofit performed on a public community facility for the performing arts. This facility originally consisted of two mess halls built by the American army. The exterior retrofit consisted of constructing a super-insulated passageway to link the two halls as well as completely wrapping the facility with six millimetre polyethylene to provide an airtight barrier. The roofs and walls were reinsulated and insulation levels were increased to RSI 10.5 in the ceilings and RSI 7.7 in the walls. The installation of a propane fuelled furnace was also included in the retrofit package. Prior to the renovations and retrofitting, the Guild Hall facility was almost unusable. The demonstration project transformed the cold, drafty buildings into an attractive, comfortable and functional centre for the performing arts. Heating requirements have been reduced to 500 MJ/m {sup 2} of floor space annually compared to a predicted 1,760 MJ/m{sup 2} of floor space based on HOTCAN analysis of the heating requirements without the energy conservation measures. 9 figs., 10 tabs.

  10. Quantum critical Hall exponents

    CERN Document Server

    Lütken, C A

    2014-01-01

    We investigate a finite size "double scaling" hypothesis using data from an experiment on a quantum Hall system with short range disorder [1-3]. For Hall bars of width w at temperature T the scaling form is w(-mu)T(-kappa), where the critical exponent mu approximate to 0.23 we extract from the data is comparable to the multi-fractal exponent alpha(0) - 2 obtained from the Chalker-Coddington (CC) model [4]. We also use the data to find the approximate location (in the resistivity plane) of seven quantum critical points, all of which closely agree with the predictions derived long ago from the modular symmetry of a toroidal sigma-model with m matter fields [5]. The value nu(8) = 2.60513 ... of the localisation exponent obtained from the m = 8 model is in excellent agreement with the best available numerical value nu(num) = 2.607 +/- 0.004 derived from the CC-model [6]. Existing experimental data appear to favour the m = 9 model, suggesting that the quantum Hall system is not in the same universality class as th...

  11. Topological Hall and Spin Hall Effects in Disordered Skyrmionic Textures

    OpenAIRE

    N'diaye, P. B.; Akosa, C. A.; Manchon, A.

    2016-01-01

    We carry out a throughout study of the topological Hall and topological spin Hall effects in disordered skyrmionic systems: the dimensionless (spin) Hall angles are evaluated across the energy band structure in the multiprobe Landauer-B\\"uttiker formalism and their link to the effective magnetic field emerging from the real space topology of the spin texture is highlighted. We discuss these results for an optimal skyrmion size and for various sizes of the sample and found that the adiabatic a...

  12. Quantum hall effect. A perspective

    International Nuclear Information System (INIS)

    Aoki, Hideo

    2006-01-01

    Novel concepts and phenomena are emerging recently in the physics of quantum Hall effect. This article gives an overview, which starts from the fractional quantum Hall system viewed as an extremely strongly correlated system, and move on to present various phenomena involving internal degrees of freedom (spin and layer), non-equilibrium and optical properties, and finally the spinoff to anomalous Hall effect and the rotating Bose-Einstein condensate. (author)

  13. Magnesium Hall Thruster

    Science.gov (United States)

    Szabo, James J.

    2015-01-01

    This Phase II project is developing a magnesium (Mg) Hall effect thruster system that would open the door for in situ resource utilization (ISRU)-based solar system exploration. Magnesium is light and easy to ionize. For a Mars- Earth transfer, the propellant mass savings with respect to a xenon Hall effect thruster (HET) system are enormous. Magnesium also can be combusted in a rocket with carbon dioxide (CO2) or water (H2O), enabling a multimode propulsion system with propellant sharing and ISRU. In the near term, CO2 and H2O would be collected in situ on Mars or the moon. In the far term, Mg itself would be collected from Martian and lunar regolith. In Phase I, an integrated, medium-power (1- to 3-kW) Mg HET system was developed and tested. Controlled, steady operation at constant voltage and power was demonstrated. Preliminary measurements indicate a specific impulse (Isp) greater than 4,000 s was achieved at a discharge potential of 400 V. The feasibility of delivering fluidized Mg powder to a medium- or high-power thruster also was demonstrated. Phase II of the project evaluated the performance of an integrated, highpower Mg Hall thruster system in a relevant space environment. Researchers improved the medium power thruster system and characterized it in detail. Researchers also designed and built a high-power (8- to 20-kW) Mg HET. A fluidized powder feed system supporting the high-power thruster was built and delivered to Busek Company, Inc.

  14. Spin Hall effect transistor

    Czech Academy of Sciences Publication Activity Database

    Wunderlich, Joerg; Park, B.G.; Irvine, A.C.; Zarbo, Liviu; Rozkotová, E.; Němec, P.; Novák, Vít; Sinova, Jairo; Jungwirth, Tomáš

    2010-01-01

    Roč. 330, č. 6012 (2010), s. 1801-1804 ISSN 0036-8075 R&D Projects: GA AV ČR KAN400100652; GA MŠk LC510 EU Projects: European Commission(XE) 215368 - SemiSpinNet Grant - others:AV ČR(CZ) AP0801 Program:Akademická prémie - Praemium Academiae Institutional research plan: CEZ:AV0Z10100521 Keywords : spin Hall effect * spintronics * spin transistor Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 31.364, year: 2010

  15. Active Learning with Monty Hall in a Game Theory Class

    Science.gov (United States)

    Brokaw, Alan J.; Merz, Thomas E.

    2004-01-01

    The authors describe a game that students can play on the first day of a game theory class. The game introduces the 4 essential elements of any game and is designed so that its sequel, also played on the first day of class, has students playing the well-known Monty Hall game, which raises the question: Should you switch doors? By implementing a…

  16. Quantum Hall Electron Nematics

    Science.gov (United States)

    MacDonald, Allan

    In 2D electron systems hosted by crystals with hexagonal symmetry, electron nematic phases with spontaneously broken C3 symmetry are expected to occur in the quantum Hall regime when triplets of Landau levels associated with three different Fermi surface pockets are partially filled. The broken symmetry state is driven by intravalley Coulombic exchange interactions that favor spontaneously polarized valley occupations. I will discuss three different examples of 2D electron systems in which this type of broken symmetry state is expected to occur: i) the SnTe (111) surface, ii) the Bi (111) surface. and iii) unbalanced bilayer graphene. This type of quantum Hall electron nematic state has so far been confirmed only in the Bi (111) case, in which the anisotropic quasiparticle wavefunctions of the broken symmetry state were directly imaged. In the SnTe case the nematic state phase boundary is controlled by a competition between intravalley Coulomb interactions and intervalley scattering processes that increase in relative strength with magnetic field. An in-plane Zeeman field alters the phase diagram by lifting the three-fold Landau level degeneracy, yielding a ground state energy with 2 π/3 periodicity as a function of Zeeman-field orientation angle. I will comment on the possibility of observing similar states in the absence of a magnetic field. Supported by DOE Division of Materials Sciences and Engineering Grant DE-FG03-02ER45958.

  17. The ISOLDE hall

    CERN Multimedia

    Maximilien Brice

    2002-01-01

    Since 1992, after its move from the 600 MeV SC, ISOLDE is a customer of the Booster (then 1 GeV, now 1.4 GeV). The intense Booster beam (some 3E13 protons per pulse) is directed onto a target, from which a mixture of isotopes emanates. After ionization and electrostatic acceleration to 60 keV, they enter one of the 2 spectrometers (General Purpose Separator: GPS, and High Resolution Separator: HRS) from which the selected ions are directed to the experiments. The photos show: the REX-ISOLDE post accelerator; the mini-ball experiment; an overview of the ISOLDE hall. In the picture (_12) of the hall, the separators are behind the wall. From either of them, beams can be directed into any of the many beamlines towards the experiments, some of which are visible in the foreground. The elevated cubicle at the left is EBIS (Electron Beam Ion Source), which acts as a charge-state multiplier for the REX facility. The ions are further mass analzyzed and passed on to the linac which accelerates them to higher energies. T...

  18. Energy consumption of sport halls

    Energy Technology Data Exchange (ETDEWEB)

    1983-01-01

    The energy consumption of Finland's sports halls (ball games halls, ice hockey halls and swimming halls) represent approximately 1% of that of the country's whole building stock. In the light of the facts revealed by the energy study the potential energy saving rate in sports halls is 15-25%. The total savings would be something like FIM 30-40 million per annum, of which about a half would be achieved without energy-economic investments only by changing utilization habits and by automatic control measures. The energy-economic investments are for the most part connected with ventilation and their repayment period is from one to five years. On the basis of the energy study the following specific consumption are presented as target values: swimming halls: heat (kWh/m*H3/a)100, electricity (kWh/m*H3/a)35, water (l/m*H3/a)1000 icehockey halls (warm): heat (kWh/m*H3/a)25, electricity (kWh/m*H3/a)15, water (l/m*H3/a)200, ball games halls (multi-purpose halls): heat (kWh/m*H3/a)30, electricity (kWh/m*H3/a)25, water (l/m*H3/a)130. In the study the following points proved to be the central areas of energy saving in sports halls: 1. Flexible regulation of the temperature in sports spaces on the basis of the sport in question. 2. The ventilation of swimming halls should be adjusted in such a way that the humidity of the hall air would comply with the limit humidity curve determined by the quality of structures and the temperature of the outdoor air. 3. An ice skating hall is an establishment producing condensing energy from 8 to 9 months a year worth of approx. 100.000-150.000 Finnmarks. The development of the recovery of condensing energy has become more important. 4. The ventilation of ball games halls may account for over 50% of the energy consumption of the whole building. Therefore special attention should be paid to the optimatization of ventilation as a whole.

  19. Scanning vector Hall probe microscopy

    International Nuclear Information System (INIS)

    Cambel, V.; Gregusova, D.; Fedor, J.; Kudela, R.; Bending, S.J.

    2004-01-01

    We have developed a scanning vector Hall probe microscope for mapping magnetic field vector over magnetic samples. The microscope is based on a micromachined Hall sensor and the cryostat with scanning system. The vector Hall sensor active area is ∼5x5 μm 2 . It is realized by patterning three Hall probes on the tilted faces of GaAs pyramids. Data from these 'tilted' Hall probes are used to reconstruct the full magnetic field vector. The scanning area of the microscope is 5x5 mm 2 , space resolution 2.5 μm, field resolution ∼1 μT Hz -1/2 at temperatures 10-300 K

  20. On Hall current fluid

    International Nuclear Information System (INIS)

    Shen, M.C.; Ebel, D.

    1987-01-01

    In this paper some new results concerning magnetohydrodynamic (MHD) equations with the Hall current (HC) term in the Ohm's law are presented. For the cylindrical pinch of a compressible HC fluid, it is found that for large time and long wave length the solution to the governing equations exhibits the behavior of solitons as in the case of an ideal MHD model. In some special cases, the HC model appears to be better posed. An open question is whether a simple toroidal equilibrium of an HC fluid with resistivity and viscosity exists. The answer to this question is affirmative if the prescribed velocity on the boundary has a small norm. Furthermore, the equilibrium is also linearly and nonlinearly stable

  1. Farm Hall: The Play

    Science.gov (United States)

    Cassidy, David C.

    2013-03-01

    It's July 1945. Germany is in defeat and the atomic bombs are on their way to Japan. Under the direction of Samuel Goudsmit, the Allies are holding some of the top German nuclear scientists-among them Heisenberg, Hahn, and Gerlach-captive in Farm Hall, an English country manor near Cambridge, England. As secret microphones record their conversations, the scientists are unaware of why they are being held or for how long. Thinking themselves far ahead of the Allies, how will they react to the news of the atomic bombs? How will these famous scientists explain to themselves and to the world their failure to achieve even a chain reaction? How will they come to terms with the horror of the Third Reich, their work for such a regime, and their behavior during that period? This one-act play is based upon the transcripts of their conversations as well as the author's historical work on the subject.

  2. Quantum Hall effect

    International Nuclear Information System (INIS)

    Joynt, R.J.

    1982-01-01

    A general investigation of the electronic structure of two dimensional systems is undertaken with a view towards understanding the quantum Hall effect. The work is limited to the case of a strong perpendicular magnetic field, with a disordered potential and an externally applied electric field. The electrons are treated as noninteracting. First, the scattering theory of the system is worked out. The surprising result is found that a wavepacket will reform after scattering from an isolated potential. Also it will tend to be accelerated in the neighborhood of the scatterer if the potential has bound states. Fredholm theory can then be used to show that the extended states carry an additional current which compensates for the zero current of the bound states. Together, these give the quantized conductance. The complementary case of a smooth random potential is treated by a path-integral approach which exploits the analogies to the classical equations of motion. The Green's function can be calculated approximately, which gives the general character of both the bound and extended states. Also the ratio of these two types of states can be computed for a given potential. The charge density is uniform in first approximation, and the Hall conductance is quantized. Higher-order corrections for more rapidly fluctuating potential are calculated. The most general conditions under which the conductance is quantized are discussed. Because of the peculiar scattering properties of the system, numerical solution of the Schroedinger equation is of interest, both to confirm the analytical results, and for pedagogical reasons. The stability and convergence problems inherent in the computer solution of the problem are analyzed. Results for some model scattering potentials are presented

  3. Hall Effect Gyrators and Circulators

    Science.gov (United States)

    Viola, Giovanni; DiVincenzo, David P.

    2014-04-01

    The electronic circulator and its close relative the gyrator are invaluable tools for noise management and signal routing in the current generation of low-temperature microwave systems for the implementation of new quantum technologies. The current implementation of these devices using the Faraday effect is satisfactory but requires a bulky structure whose physical dimension is close to the microwave wavelength employed. The Hall effect is an alternative nonreciprocal effect that can also be used to produce desired device functionality. We review earlier efforts to use an Ohmically contacted four-terminal Hall bar, explaining why this approach leads to unacceptably high device loss. We find that capacitive coupling to such a Hall conductor has much greater promise for achieving good circulator and gyrator functionality. We formulate a classical Ohm-Hall analysis for calculating the properties of such a device, and show how this classical theory simplifies remarkably in the limiting case of the Hall angle approaching 90°. In this limit, we find that either a four-terminal or a three-terminal capacitive device can give excellent circulator behavior, with device dimensions far smaller than the ac wavelength. An experiment is proposed to achieve GHz-band gyration in millimeter (and smaller) scale structures employing either semiconductor heterostructure or graphene Hall conductors. An inductively coupled scheme for realizing a Hall gyrator is also analyzed.

  4. Topological Hall and spin Hall effects in disordered skyrmionic textures

    KAUST Repository

    Ndiaye, Papa Birame; Akosa, Collins Ashu; Manchon, Aurelien

    2017-01-01

    We carry out a thorough study of the topological Hall and topological spin Hall effects in disordered skyrmionic systems: the dimensionless (spin) Hall angles are evaluated across the energy-band structure in the multiprobe Landauer-Büttiker formalism and their link to the effective magnetic field emerging from the real-space topology of the spin texture is highlighted. We discuss these results for an optimal skyrmion size and for various sizes of the sample and find that the adiabatic approximation still holds for large skyrmions as well as for nanoskyrmions. Finally, we test the robustness of the topological signals against disorder strength and show that the topological Hall effect is highly sensitive to momentum scattering.

  5. Topological Hall and spin Hall effects in disordered skyrmionic textures

    KAUST Repository

    Ndiaye, Papa Birame

    2017-02-24

    We carry out a thorough study of the topological Hall and topological spin Hall effects in disordered skyrmionic systems: the dimensionless (spin) Hall angles are evaluated across the energy-band structure in the multiprobe Landauer-Büttiker formalism and their link to the effective magnetic field emerging from the real-space topology of the spin texture is highlighted. We discuss these results for an optimal skyrmion size and for various sizes of the sample and find that the adiabatic approximation still holds for large skyrmions as well as for nanoskyrmions. Finally, we test the robustness of the topological signals against disorder strength and show that the topological Hall effect is highly sensitive to momentum scattering.

  6. Tuning giant anomalous Hall resistance ratio in perpendicular Hall balance

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, J. Y.; Yang, G. [Department of Materials Physics and Chemistry, University of Science and Technology Beijing, Beijing 100083 (China); State Key Laboratory of Magnetism, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Wang, S. G., E-mail: sgwang@iphy.ac.cn, E-mail: ghyu@mater.ustb.edu.cn [State Key Laboratory of Magnetism, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Liu, J. L. [State Key Laboratory of Magnetism, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Department of Physics, Beijing University of Aeronautics and Astronautics, Beijing 100191 (China); Wang, R. M. [Department of Physics, Beijing University of Aeronautics and Astronautics, Beijing 100191 (China); Amsellem, E.; Kohn, A. [Department of Materials Engineering, Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer-Sheva 84105 (Israel); Yu, G. H., E-mail: sgwang@iphy.ac.cn, E-mail: ghyu@mater.ustb.edu.cn [Department of Materials Physics and Chemistry, University of Science and Technology Beijing, Beijing 100083 (China)

    2015-04-13

    Anomalous Hall effect at room temperature in perpendicular Hall balance with a core structure of [Pt/Co]{sub 4}/NiO/[Co/Pt]{sub 4} has been tuned by functional CoO layers, where [Pt/Co]{sub 4} multilayers exhibit perpendicular magnetic anisotropy. A giant Hall resistance ratio up to 69 900% and saturation Hall resistance (R{sub S}{sup P}) up to 2590 mΩ were obtained in CoO/[Pt/Co]{sub 4}/NiO/[Co/Pt]{sub 4}/CoO system, which is 302% and 146% larger than that in the structure without CoO layers, respectively. Transmission electron microscopy shows highly textured [Co/Pt]{sub 4} multilayers and oxide layers with local epitaxial relations, indicating that the crystallographic structure has significant influence on spin dependent transport properties.

  7. Changes in Roles and Behavior of Learners and Teachers When Going for POPBL On-campus as well as On-line

    DEFF Research Database (Denmark)

    Borch, Ole; Helbo, Jan; Madsen, Per Printz

    2006-01-01

    , and traditions. Students need to be more active in the learning process so the concern is more work. It is always difficult to make major changes in an (mature) educational institution, but shifting to POPBL collaborative learning has been proven to be a successful learning method at Aalborg University, Denmark...... of information technology (IT), pedagogy and didactic methods requires new demands to all parties in openness, willingness, and readiness in adapting new roles and behavior. This article describes challenges and changes in roles and behavior when going for and maintaining a modern and successful POPBL...... environment. Based on years of POPBL development and experience - methods and recommendations will be presented to staff and students when working with the courses and projects in an on-campus, as well as on-line POPBL educational environment....

  8. The Role of Social Influence on How Residence Hall Inhabitants Respond to Fire Alarms

    Science.gov (United States)

    Leytem, Michael; Stark, Emily

    2016-01-01

    College resident halls pose a threat for a catastrophic event in the case of fire, but little research has examined potential influences on students' responses to fire alarms, particularly the role of social influence in affecting their behaviors. In the current study, residence hall inhabitants reported their knowledge about fire safety, their…

  9. Anomalous Hall effect

    Science.gov (United States)

    Nagaosa, Naoto; Sinova, Jairo; Onoda, Shigeki; MacDonald, A. H.; Ong, N. P.

    2010-04-01

    The anomalous Hall effect (AHE) occurs in solids with broken time-reversal symmetry, typically in a ferromagnetic phase, as a consequence of spin-orbit coupling. Experimental and theoretical studies of the AHE are reviewed, focusing on recent developments that have provided a more complete framework for understanding this subtle phenomenon and have, in many instances, replaced controversy by clarity. Synergy between experimental and theoretical works, both playing a crucial role, has been at the heart of these advances. On the theoretical front, the adoption of the Berry-phase concepts has established a link between the AHE and the topological nature of the Hall currents. On the experimental front, new experimental studies of the AHE in transition metals, transition-metal oxides, spinels, pyrochlores, and metallic dilute magnetic semiconductors have established systematic trends. These two developments, in concert with first-principles electronic structure calculations, strongly favor the dominance of an intrinsic Berry-phase-related AHE mechanism in metallic ferromagnets with moderate conductivity. The intrinsic AHE can be expressed in terms of the Berry-phase curvatures and it is therefore an intrinsic quantum-mechanical property of a perfect crystal. An extrinsic mechanism, skew scattering from disorder, tends to dominate the AHE in highly conductive ferromagnets. The full modern semiclassical treatment of the AHE is reviewed which incorporates an anomalous contribution to wave-packet group velocity due to momentum-space Berry curvatures and correctly combines the roles of intrinsic and extrinsic (skew-scattering and side-jump) scattering-related mechanisms. In addition, more rigorous quantum-mechanical treatments based on the Kubo and Keldysh formalisms are reviewed, taking into account multiband effects, and demonstrate the equivalence of all three linear response theories in the metallic regime. Building on results from recent experiment and theory, a

  10. Planar Hall effect bridge magnetic field sensors

    DEFF Research Database (Denmark)

    Henriksen, A.D.; Dalslet, Bjarke Thomas; Skieller, D.H.

    2010-01-01

    Until now, the planar Hall effect has been studied in samples with cross-shaped Hall geometry. We demonstrate theoretically and experimentally that the planar Hall effect can be observed for an exchange-biased ferromagnetic material in a Wheatstone bridge topology and that the sensor signal can...... Hall effect bridge sensors....

  11. Gauge invariance and fractional quantized Hall effect

    International Nuclear Information System (INIS)

    Tao, R.; Wu, Y.S.

    1984-01-01

    It is shown that gauge invariance arguments imply the possibility of fractional quantized Hall effect; the Hall conductance is accurately quantized to a rational value. The ground state of a system showing the fractional quantized Hall effect must be degenerate; the non-degenerate ground state can only produce the integral quantized Hall effect. 12 references

  12. "Hall mees" Linnateatris / Triin Sinissaar

    Index Scriptorium Estoniae

    Sinissaar, Triin

    1999-01-01

    Tallinn Linnateatri ja Raadioteatri ühislavastus "Hall mees" Gill Adamsi näidendi järgi, lavastaja Eero Spriit, osades Helene Vannari ja Väino Laes, kunstnik Kustav - Agu Püüman. Esietendus 22. okt

  13. Sheldon-Hall syndrome

    Directory of Open Access Journals (Sweden)

    Bamshad Michael J

    2009-03-01

    Full Text Available Abstract Sheldon-Hall syndrome (SHS is a rare multiple congenital contracture syndrome characterized by contractures of the distal joints of the limbs, triangular face, downslanting palpebral fissures, small mouth, and high arched palate. Epidemiological data for the prevalence of SHS are not available, but less than 100 cases have been reported in the literature. Other common clinical features of SHS include prominent nasolabial folds, high arched palate, attached earlobes, mild cervical webbing, short stature, severe camptodactyly, ulnar deviation, and vertical talus and/or talipes equinovarus. Typically, the contractures are most severe at birth and non-progressive. SHS is inherited in an autosomal dominant pattern but about half the cases are sporadic. Mutations in either MYH3, TNNI2, or TNNT3 have been found in about 50% of cases. These genes encode proteins of the contractile apparatus of fast twitch skeletal muscle fibers. The diagnosis of SHS is based on clinical criteria. Mutation analysis is useful to distinguish SHS from arthrogryposis syndromes with similar features (e.g. distal arthrogryposis 1 and Freeman-Sheldon syndrome. Prenatal diagnosis by ultrasonography is feasible at 18–24 weeks of gestation. If the family history is positive and the mutation is known in the family, prenatal molecular genetic diagnosis is possible. There is no specific therapy for SHS. However, patients benefit from early intervention with occupational and physical therapy, serial casting, and/or surgery. Life expectancy and cognitive abilities are normal.

  14. Anode sheath in Hall thrusters

    International Nuclear Information System (INIS)

    Dorf, L.; Semenov, V.; Raitses, Y.

    2003-01-01

    A set of hydrodynamic equations is used to describe quasineutral plasma in ionization and acceleration regions of a Hall thruster. The electron distribution function and Poisson equation are invoked for description of a near-anode region. Numerical solutions suggest that steady-state operation of a Hall thruster can be achieved at different anode sheath regimes. It is shown that the anode sheath depends on the thruster operating conditions, namely the discharge voltage and the mass flow rate

  15. Theory of spin Hall effect

    OpenAIRE

    Chudnovsky, Eugene M.

    2007-01-01

    An extension of Drude model is proposed that accounts for spin and spin-orbit interaction of charge carriers. Spin currents appear due to combined action of the external electric field, crystal field and scattering of charge carriers. The expression for spin Hall conductivity is derived for metals and semiconductors that is independent of the scattering mechanism. In cubic metals, spin Hall conductivity $\\sigma_s$ and charge conductivity $\\sigma_c$ are related through $\\sigma_s = [2 \\pi \\hbar...

  16. Optimization of Cylindrical Hall Thrusters

    International Nuclear Information System (INIS)

    Raitses, Yevgeny; Smirnov, Artem; Granstedt, Erik; Fisch, Nathaniel J.

    2007-01-01

    The cylindrical Hall thruster features high ionization efficiency, quiet operation, and ion acceleration in a large volume-to-surface ratio channel with performance comparable with the state-of-the-art annular Hall thrusters. These characteristics were demonstrated in low and medium power ranges. Optimization of miniaturized cylindrical thrusters led to performance improvements in the 50-200W input power range, including plume narrowing, increased thruster efficiency, reliable discharge initiation, and stable operation.

  17. Optimization of Cylindrical Hall Thrusters

    International Nuclear Information System (INIS)

    Raitses, Yevgeny; Smirnov, Artem; Granstedt, Erik; Fi, Nathaniel J.

    2007-01-01

    The cylindrical Hall thruster features high ionization efficiency, quiet operation, and ion acceleration in a large volume-to-surface ratio channel with performance comparable with the state-of-the-art annular Hall thrusters. These characteristics were demonstrated in low and medium power ranges. Optimization of miniaturized cylindrical thrusters led to performance improvements in the 50-200W input power range, including plume narrowing, increased thruster efficiency, reliable discharge initiation, and stable operation

  18. Not your grandfather's concert hall

    Science.gov (United States)

    Cooper, Russell; Malenka, Richard; Griffith, Charles; Friedlander, Steven

    2004-05-01

    The opening of Judy and Arthur Zankel Hall on 12 September 2003, restores Andrew Carnegie's original 1891 concept of having three outstanding auditoriums of different sizes under one roof, and creates a 21st-century venue for music performance and education. With concerts ranging from early music to avant-garde multimedia productions, from jazz to world music, and from solo recitals to chamber music, Zankel Hall expands the breadth and depth of Carnegie Hall's offerings. It allows for the integration of programming across three halls with minifestivals tailored both to the size and strengths of each hall and to the artists and music to be performed. The new flexible space also provides Carnegie Hall with an education center equipped with advanced communications technology. This paper discusses the unique program planned for this facility and how the architects, theatre consultants, and acousticians developed a design that fulfilled the client's expectations and coordinated the construction of the facility under the floor of the main Isaac Stern Auditorium without having to cancel a single performance.

  19. Dancing in the Hall

    Science.gov (United States)

    Schneier, Lisa

    2018-01-01

    Originally written 30 years ago, this paper is an analysis of the central challenge of schooling--that of engaging fully the powers of students' minds in classroom learning. This challenge maintains its relevance today. The work of engaging what John Dewey referred to as students' "inner attention" becomes the focus of an investigation…

  20. Iodine Hall Thruster

    Science.gov (United States)

    Szabo, James

    2015-01-01

    Iodine enables dramatic mass and cost savings for lunar and Mars cargo missions, including Earth escape and near-Earth space maneuvers. The demonstrated throttling ability of iodine is important for a singular thruster that might be called upon to propel a spacecraft from Earth to Mars or Venus. The ability to throttle efficiently is even more important for missions beyond Mars. In the Phase I project, Busek Company, Inc., tested an existing Hall thruster, the BHT-8000, on iodine propellant. The thruster was fed by a high-flow iodine feed system and supported by an existing Busek hollow cathode flowing xenon gas. The Phase I propellant feed system was evolved from a previously demonstrated laboratory feed system. Throttling of the thruster between 2 and 11 kW at 200 to 600 V was demonstrated. Testing showed that the efficiency of iodine fueled BHT-8000 is the same as with xenon, with iodine delivering a slightly higher thrust-to-power (T/P) ratio. In Phase II, a complete iodine-fueled system was developed, including the thruster, hollow cathode, and iodine propellant feed system. The nominal power of the Phase II system is 8 kW; however, it can be deeply throttled as well as clustered to much higher power levels. The technology also can be scaled to greater than 100 kW per thruster to support megawatt-class missions. The target thruster efficiency for the full-scale system is 65 percent at high specific impulse (Isp) (approximately 3,000 s) and 60 percent at high thrust (Isp approximately 2,000 s).

  1. From Soldier to Student: Easing the Transition of Service Members on Campus

    Science.gov (United States)

    Cook, Bryan J.; Kim, Young

    2009-01-01

    This report offers a first-of-its-kind national snapshot of the programs, services, and policies that campuses have in place to serve veterans and military personnel. The partner organizations hope that it will prompt colleges and universities to follow California State University Chancellor Charlie Reed's advice and take a close look at their own…

  2. "I Can Fix That!" Creating an On-Campus Job for a Student

    Science.gov (United States)

    Crow, Nita

    2008-01-01

    Every year on or near October 15, the California School for Blind celebrates National White Cane Day. Over the years, all kinds of events have been planned to celebrate the day. About two years ago, the school decided to do something different. Early that fall, staff members in the Orientation and Mobility Department at the school started teaching…

  3. ac spin-Hall effect

    International Nuclear Information System (INIS)

    Entin-Wohlman, O.

    2005-01-01

    Full Text:The spin-Hall effect is described. The Rashba and Dresselhaus spin-orbit interactions are both shown to yield the low temperature spin-Hall effect for strongly localized electrons coupled to phonons. A frequency-dependent electric field E(ω) generates a spin-polarization current, normal to E, due to interference of hopping paths. At zero temperature the corresponding spin-Hall conductivity is real and is proportional to ω 2 . At non-zero temperatures the coupling to the phonons yields an imaginary term proportional to ω. The interference also yields persistent spin currents at thermal equilibrium, at E = 0. The contributions from the Dresselhaus and Rashba interactions to the interference oppose each other

  4. Digital Product Marketing Strategy on Campus%校园数码产品的营销战略

    Institute of Scientific and Technical Information of China (English)

    石研

    2011-01-01

    本文分析了校园市场以及IT数码产品的特点,并通过对IT数码产品在校园营销中存在的一些问题及大学生对数码产品的需求特点分析,得出了IT数码产品校园营销的策略。%This paper analyzes the market on campus and IT digital product characteristics,and through the IT digital product some problems in marketing on campus and college students' demanding characteristics for digital products,the author obtained IT digital pro

  5. Measurement-based Channel Characterization for 5G Wireless Communications on Campus Scenario

    DEFF Research Database (Denmark)

    Mi, Yang; He, Ruisi; Ai, Bo

    2017-01-01

    The fifth generation (5G) communication has been a hotspot of research in recent years, and both research institutions and industrial enterprises put a lot of interests for 5G communication at some new frequency bands. In this paper, we investigate the radio channels of 5G communications below 6...... GHz according to the requirements and scenarios of 5G communication. Channel measurements were conducted on campus of Beijing Jiaotong University, China at two key optional frequency bands below 6 GHz. By using the measured data, we analyzed key channel parameters at 460MHz and 3.5GHz, such as power...... delay profile, path loss exponent, shadow fading, and delay spread. The results are helpful for the 5G communication system design....

  6. Residencia hall del Obispado, en Gescher, Alemania

    Directory of Open Access Journals (Sweden)

    Deilmann, Harald

    1969-02-01

    Full Text Available This Hall has four lecture rooms, each with a capacity for twenty students. They all face north, have lateral and cenithal illumination and cross ventilation. The workshop training halls face south, and there is a gymnasium. Each classroom is also connected with a protected open air space, so that in suitable weather, teaching can be practised out of doors. As the school is devoted to mentally retarded boys and youths, over 2 m2 of floor area has been allowed for each student in the classrooms, since it was estimated that many students would be of the nervous type and would need more room to work freely. Most of the construction is made with unfaced brick and concrete, which are long lasting materials, requiring little maintenance.Comprende cuatro clases propiamente dichas, con una capacidad total de 80 alumnos, a razón de 20 por cada clase, y orientadas al norte, con iluminación cenital y lateral y ventilación cruzada. Los locales donde se imparten las enseñanzas de taller tienen orientación sur. Se ha previsto, además, un gimnasio. Cada clase dispone de un recinto protegido para que, cuando las condiciones atmosféricas lo permitan, se pueda desarrollar en él la enseñanza al aire libre. Como la escuela está destinada a niños y adolescentes retrasados mentales, se partió de un espacio superior a los 2 m2 por alumno, pensando en que parte de ellos iban a ser niños nerviosos y, como consecuencia, la necesidad que tendrían de amplitud suficiente para desenvolverse adecuadamente. La construcción se ha desarrollado, en general, a base de fábrica de ladrillo a cara vista y hormigón visto, materiales de gran duración y prácticamente exentos de entretenimiento.

  7. ATLAS Assembly Hall Open Day

    CERN Multimedia

    Patrice Loiez

    2004-01-01

    To mark the 50th Anniversary of the founding of CERN, a day of tours, displays and presentations was held in October 2004. The assembly halls for the experiments that were waiting to be installed on the LHC, such as ATLAS shown here, were transformed into display areas and cafés.

  8. Universal intrinsic spin Hall effect

    Czech Academy of Sciences Publication Activity Database

    Sinova, J.; Culcer, D.; Sinitsyn, N. A.; Niu, Q.; Jungwirth, Tomáš; MacDonald, A. H.

    2004-01-01

    Roč. 92, č. 12 (2004), 126603/1-126603/4 ISSN 0031-9007 R&D Projects: GA ČR GA202/02/0912 Institutional research plan: CEZ:AV0Z1010914 Keywords : semiconductor quantum wells * spin-orbit interaction * spin Hall effect Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 7.218, year: 2004

  9. Spin Hall effect for anyons

    International Nuclear Information System (INIS)

    Dhar, S.; Basu, B.; Ghosh, Subir

    2007-01-01

    We explain the intrinsic spin Hall effect from generic anyon dynamics in the presence of external electromagnetic field. The free anyon is represented as a spinning particle with an underlying non-commutative configuration space. The Berry curvature plays a major role in the analysis

  10. The Other Hall Effect: College Board Physics

    Science.gov (United States)

    Sheppard, Keith; Gunning, Amanda M.

    2013-01-01

    Edwin Herbert Hall (1855-1938), discoverer of the Hall effect, was one of the first winners of the AAPT Oersted Medal for his contributions to the teaching of physics. While Hall's role in establishing laboratory work in high schools is widely acknowledged, his position as chair of the physics section of the Committee on College Entrance…

  11. When Push Comes to Shove: A Hype-Free Guide to Evaluating Technical Solutions to Copyright Infringement on Campus Networks

    Science.gov (United States)

    Electronic Frontier Foundation, 2006

    2006-01-01

    This paper is intended to help institutions of higher education critically evaluate the principal technological tools and policies being used to enforce copyright on campus networks. It first explores where the goals of copyright holders and universities overlap and where they conflict. It then discusses the pros and cons of the major solutions…

  12. The Actively Caring for People Movement at Virginia Tech and Beyond: Cultivating Compassion and Relationships in Residence Halls

    Science.gov (United States)

    McCarty, Shane M.; Mullins, Taris G.; Geller, E. Scott; Shushok, Frank, Jr.

    2013-01-01

    A professor and a group of student leaders initiated the Actively Caring for People (AC4P) Movement to establish a more civil, compassionate, and inclusive culture by inspiring intentional acts of kindness. This article explores the AC4P Movement in a first-year residence hall at Virginia Tech and a second-year residence hall at University of…

  13. Hall effect in noncommutative coordinates

    International Nuclear Information System (INIS)

    Dayi, Oemer F.; Jellal, Ahmed

    2002-01-01

    We consider electrons in uniform external magnetic and electric fields which move on a plane whose coordinates are noncommuting. Spectrum and eigenfunctions of the related Hamiltonian are obtained. We derive the electric current whose expectation value gives the Hall effect in terms of an effective magnetic field. We present a receipt to find the action which can be utilized in path integrals for noncommuting coordinates. In terms of this action we calculate the related Aharonov-Bohm phase and show that it also yields the same effective magnetic field. When magnetic field is strong enough this phase becomes independent of magnetic field. Measurement of it may give some hints on spatial noncommutativity. The noncommutativity parameter θ can be tuned such that electrons moving in noncommutative coordinates are interpreted as either leading to the fractional quantum Hall effect or composite fermions in the usual coordinates

  14. General vibration monitoring: Experimental hall

    International Nuclear Information System (INIS)

    Jendrzejczyk, J.A.; Wambsganss, M.W.; Smith, R.K.

    1993-01-01

    The reported vibration data were generated from measurements made on the experimental hall floor on December 2, 1992. At the time of the measurements, the ESRF hydrolevel was set-up in the Early Assembly Area (EAA) of the experimental hall and was being used to measure static displacement (settlement) of the floor. The vibration measurement area was on and adjacent to the EAA, in the vicinity of the ESRF hydrolevel test which was in progress. This report summarizes the objectives, instrumentation, measurement locations, observations, and conclusions, and provides selected results in the form of RMS vs. time plots, and power spectral densities from which frequency information can be derived. Measured response amplitudes were within the vibration criteria established for the APS

  15. Scanning vector Hall probe microscope

    Czech Academy of Sciences Publication Activity Database

    Fedor, J.; Cambel, V.; Gregušová, D.; Hanzelka, Pavel; Dérer, J.; Volko, J.

    2003-01-01

    Roč. 74, č. 12 (2003), s. 5105 - 5110 ISSN 0034-6748 Institutional research plan: CEZ:AV0Z2065902 Keywords : VHPM * Hall sensor * Helium cryostat Subject RIV: JB - Sensors, Measurment, Regulation Impact factor: 1.343, year: 2003 http://web. ebscohost .com/ehost/pdf?vid=8&hid=115&sid=a7c0555a-21f4-4932-b1c6-a308ac4dd50b%40sessionmgr2

  16. Construction Policies on Campus An Analytical Study of the Policy of Construction Planning on Kufa Campus

    Directory of Open Access Journals (Sweden)

    Talib Hamid Altalib

    2017-06-01

    Full Text Available University Campuses, as any lively physical entity, is subject to continuous variation due to . growth, development and change. This reality covers the existing or futuristic additives or additions, consecutively these changes may have a strong sensation of disorientation as a result of formatic changes in buildings, or in movement paths. And it epitomized the research problem to "the need for knowledge to clarify the impact of intellectual and executive policy in achieving coherence, functional and space organization of the elements of the university urban environment and in the stages of future growth and change," the search targeted "to highlight the study of constraction politics on campus Bmqomadtha intellectual and executive , as well as clarify the role of the executive policy in the application of thought, "and formulated the hypothesis search " urban policy affect Bmqomadtha (intellectual and executive on the process of organizing and homogeneity of the university urban environment to make them adapted to future changes, "the University of Kufa it was chosen as the campus to represent the experimental field of research.

  17. L'effet Hall Quantique

    Science.gov (United States)

    Samson, Thomas

    Nous proposons une methode permettant d'obtenir une expression pour la conductivite de Hall de structures electroniques bidimensionnelles et nous examinons celle -ci a la limite d'une temperature nulle dans le but de verifier l'effet Hall quantique. Nous allons nous interesser essentiellement a l'effet Hall quantique entier et aux effets fractionnaires inferieurs a un. Le systeme considere est forme d'un gaz d'electrons en interaction faible avec les impuretes de l'echantillon. Le modele du gaz d'electrons consiste en un gaz bidimensionnel d'electrons sans spin expose perpendiculairement a un champ magnetique uniforme. Ce dernier est decrit par le potentiel vecteur vec{rm A} defini dans la jauge de Dingle ou jauge symetrique. Conformement au formalisme de la seconde quantification, l'hamiltonien de ce gaz est represente dans la base des etats a un-corps de Dingle |n,m> et exprime ainsi en terme des operateurs de creation et d'annihilation correspondants a_sp{ rm n m}{dag} et a _{rm n m}. Nous supposons de plus que les electrons du niveau fondamental de Dingle interagissent entre eux via le potentiel coulombien. La methode utilisee fait appel a une equation mai tresse a N-corps, de nature quantique et statistique, et verifiant le second principe de la thermodynamique. A partir de celle-ci, nous obtenons un systeme d'equations differentielles appele hierarchie d'equations quantique dont la resolution nous permet de determiner une equation a un-corps, dite de Boltzmann quantique, et dictant l'evolution de la moyenne statistique de l'operateur non-diagonal a _sp{rm n m}{dag } a_{rm n}, _{rm m}, sous l'action du champ electrique applique vec{rm E}(t). C'est sa solution Tr(p(t) a _sp{rm n m}{dag} a_{rm n},_ {rm m}), qui definit la relation de convolution entre la densite courant de Hall vec{rm J}_{rm H }(t) et le champ electrique vec {rm E}(t) dont la transformee de Laplace-Fourier du noyau nous fournit l'expression de la conductivite de Hall desiree. Pour une valeur de

  18. Spin Hall effect by surface roughness

    KAUST Repository

    Zhou, Lingjun

    2015-01-08

    The spin Hall and its inverse effects, driven by the spin orbit interaction, provide an interconversion mechanism between spin and charge currents. Since the spin Hall effect generates and manipulates spin current electrically, to achieve a large effect is becoming an important topic in both academia and industries. So far, materials with heavy elements carrying a strong spin orbit interaction, provide the only option. We propose here a new mechanism, using the surface roughness in ultrathin films, to enhance the spin Hall effect without heavy elements. Our analysis based on Cu and Al thin films suggests that surface roughness is capable of driving a spin Hall angle that is comparable to that in bulk Au. We also demonstrate that the spin Hall effect induced by surface roughness subscribes only to the side-jump contribution but not the skew scattering. The paradigm proposed in this paper provides the second, not if only, alternative to generate a sizable spin Hall effect.

  19. Tunneling Anomalous and Spin Hall Effects.

    Science.gov (United States)

    Matos-Abiague, A; Fabian, J

    2015-07-31

    We predict, theoretically, the existence of the anomalous Hall effect when a tunneling current flows through a tunnel junction in which only one of the electrodes is magnetic. The interfacial spin-orbit coupling present in the barrier region induces a spin-dependent momentum filtering in the directions perpendicular to the tunneling current, resulting in a skew tunneling even in the absence of impurities. This produces an anomalous Hall conductance and spin Hall currents in the nonmagnetic electrode when a bias voltage is applied across the tunneling heterojunction. If the barrier is composed of a noncentrosymmetric material, the anomalous Hall conductance and spin Hall currents become anisotropic with respect to both the magnetization and crystallographic directions, allowing us to separate this interfacial phenomenon from the bulk anomalous and spin Hall contributions. The proposed effect should be useful for proving and quantifying the interfacial spin-orbit fields in metallic and metal-semiconductor systems.

  20. Observation of the Zero Hall Plateau in a Quantum Anomalous Hall Insulator

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Yang; Feng, Xiao; Ou, Yunbo; Wang, Jing; Liu, Chang; Zhang, Liguo; Zhao, Dongyang; Jiang, Gaoyuan; Zhang, Shou-Cheng; He, Ke; Ma, Xucun; Xue, Qi-Kun; Wang, Yayu

    2015-09-16

    We report experimental investigations on the quantum phase transition between the two opposite Hall plateaus of a quantum anomalous Hall insulator. We observe a well-defined plateau with zero Hall conductivity over a range of magnetic field around coercivity when the magnetization reverses. The features of the zero Hall plateau are shown to be closely related to that of the quantum anomalous Hall effect, but its temperature evolution exhibits a significant difference from the network model for a conventional quantum Hall plateau transition. We propose that the chiral edge states residing at the magnetic domain boundaries, which are unique to a quantum anomalous Hall insulator, are responsible for the novel features of the zero Hall plateau.

  1. Anomalous Hall effect in polycrystalline Ni films

    KAUST Repository

    Guo, Zaibing

    2012-02-01

    We systematically studied the anomalous Hall effect in a series of polycrystalline Ni films with thickness ranging from 4 to 200 nm. It is found that both the longitudinal and anomalous Hall resistivity increased greatly as film thickness decreased. This enhancement should be related to the surface scattering. In the ultrathin films (46 nm thick), weak localization corrections to anomalous Hall conductivity were studied. The granular model, taking into account the dominated intergranular tunneling, has been employed to explain this phenomenon, which can explain the weak dependence of anomalous Hall resistivity on longitudinal resistivity as well. © 2011 Elsevier Ltd. All rights reserved.

  2. Temperature Gradient in Hall Thrusters

    International Nuclear Information System (INIS)

    Staack, D.; Raitses, Y.; Fisch, N.J.

    2003-01-01

    Plasma potentials and electron temperatures were deduced from emissive and cold floating probe measurements in a 2 kW Hall thruster, operated in the discharge voltage range of 200-400 V. An almost linear dependence of the electron temperature on the plasma potential was observed in the acceleration region of the thruster both inside and outside the thruster. This result calls into question whether secondary electron emission from the ceramic channel walls plays a significant role in electron energy balance. The proportionality factor between the axial electron temperature gradient and the electric field is significantly smaller than might be expected by models employing Ohmic heating of electrons

  3. 75 FR 7467 - Gary E. Hall and Rita C. Hall; Notice of Application Accepted for Filing With the Commision...

    Science.gov (United States)

    2010-02-19

    ... Rita C. Hall; Notice of Application Accepted for Filing With the Commision, Soliciting Motions To.... Project No.: 13652-000. c. Date filed: January 11, 2010. d. Applicant: Gary E. Hall and Rita C. Hall. e... Policies Act of 1978, 16 U.S.C. 2705, 2708. h. Applicant Contact: Mr. Gary E. Hall and Ms. Rita C. Hall, P...

  4. Nondestructive hall coefficient measurements using ACPD techniques

    Science.gov (United States)

    Velicheti, Dheeraj; Nagy, Peter B.; Hassan, Waled

    2018-04-01

    Hall coefficient measurements offer great opportunities as well as major challenges for nondestructive materials characterization. The Hall effect is produced by the magnetic Lorentz force acting on moving charge carriers in the presence of an applied magnetic field. The magnetic perturbation gives rise to a Hall current that is normal to the conduction current but does not directly perturb the electric potential distribution. Therefore, Hall coefficient measurements usually exploit the so-called transverse galvanomagnetic potential drop effect that arises when the Hall current is intercepted by the boundaries of the specimen and thereby produce a measurable potential drop. In contrast, no Hall potential is produced in a large plate in the presence of a uniform normal field at quasi-static low frequencies. In other words, conventional Hall coefficient measurements are inherently destructive since they require cutting the material under tests. This study investigated the feasibility of using alternating current potential drop (ACPD) techniques for nondestructive Hall coefficient measurements in plates. Specifically, the directional four-point square-electrode configuration is investigated with superimposed external magnetic field. Two methods are suggested to make Hall coefficient measurements in large plates without destructive machining. At low frequencies, constraining the bias magnetic field can replace constraining the dimensions of the specimen, which is inherently destructive. For example, when a cylindrical permanent magnet is used to provide the bias magnetic field, the peak Hall voltage is produced when the diameter of the magnet is equal to the diagonal of the square ACPD probe. Although this method is less effective than cutting the specimen to a finite size, the loss of sensitivity is less than one order of magnitude even at very low frequencies. In contrast, at sufficiently high inspection frequencies the magnetic field of the Hall current induces a

  5. Hall magnetohydrodynamics of neutral layers

    International Nuclear Information System (INIS)

    Huba, J.D.; Rudakov, L.I.

    2003-01-01

    New analytical and numerical results of the dynamics of inhomogeneous, reversed field current layers in the Hall limit (i.e., characteristic length scales < or approx. the ion inertial length) are presented. Specifically, the two- and three-dimensional evolution of a current layer that supports a reversed field plasma configuration and has a density gradient along the current direction is studied. The two-dimensional study demonstrates that a density inhomogeneity along the current direction can dramatically redistribute the magnetic field and plasma via magnetic shock-like or rarefaction waves. The relative direction between the density gradient and current flow plays a critical role in the evolution of the current sheet. One important result is that the current sheet can become very thin rapidly when the density gradient is directed opposite to the current. The three-dimensional study uses the same plasma and field configuration as the two-dimensional study but is also initialized with a magnetic field perturbation localized along the current channel upstream of the plasma inhomogeneity. The perturbation induces a magnetic wave structure that propagates in the direction of the electron drift (i.e., opposite to the current). The propagating wave structure is a Hall phenomenon associated with magnetic field curvature. The interaction between the propagating wave structure and the evolving current layer can lead to rapid magnetic field line reconnection. The results are applied to laboratory and space plasma processes

  6. Better Together: Considering Student Interfaith Leadership and Social Change

    Science.gov (United States)

    Campbell, William; Lane, Megan

    2014-01-01

    On campuses across the country, students and professional staff are considering student interfaith leadership as one way that students act on their core values to make a positive difference in the world. This kind of student leadership can be framed through student leadership models like the social change model of leadership development. Better…

  7. The Dynamics of Social Relationships in Student Communities

    Science.gov (United States)

    AlKandari, Nabila; AlShallal, Khalid

    2008-01-01

    This study discusses the nature of social relationships in student communities at Kuwait University. Three hundred seventy-two students participated. A survey of 22 items was designed to describe students' social relationships. The study revealed that students have affirmative social relationships. The students do not feel desolation on campus;…

  8. Improving Wellness on Campus: Service Learning in a Human Nutrition Class

    Science.gov (United States)

    Wood, Bonnie

    2003-01-01

    In a human nutrition class, students are paired with university faculty or staff volunteer participants. Students teach their service learning partners how to record their food consumption and physical activity during a typical 7-day period. Using these data, students complete nutritional assessments of their partners. (Contains 2 figures.)

  9. LGBT Discrimination on Campus and Heterosexual Bystanders: Understanding Intentions to Intervene

    Science.gov (United States)

    Dessel, Adrienne B.; Goodman, Kevin D.; Woodford, Michael R.

    2017-01-01

    Discrimination targeting lesbian, gay, bisexual, and transgender (LGBT) students on college campuses occurs. Bystander intervention is important in supporting targeted students and improving campus climate for LGBT students. Peer-familiarity context (i.e., who the bystander knows in the situation) can play a role in bystander intervention, but…

  10. Quantum Hall effect in quantum electrodynamics

    International Nuclear Information System (INIS)

    Penin, Alexander A.

    2009-01-01

    We consider the quantum Hall effect in quantum electrodynamics and find a deviation from the quantum-mechanical prediction for the Hall conductivity due to radiative antiscreening of electric charge in an external magnetic field. A weak dependence of the universal von Klitzing constant on the magnetic field strength, which can possibly be observed in a dedicated experiment, is predicted

  11. Hall devices improve electric motor efficiency

    Science.gov (United States)

    Haeussermann, W.

    1979-01-01

    Efficiency of electric motors and generators is reduced by radial magnetic forces created by symmetric fields within device. Forces are sensed and counteracted by Hall devices on excitation or control windings. Hall generators directly measure and provide compensating control of anu asymmetry, eliminating additional measurements needed for calibration feedback control loop.

  12. Higher fractions theory of fractional hall effect

    International Nuclear Information System (INIS)

    Kostadinov, I.Z.; Popov, V.N.

    1985-07-01

    A theory of fractional quantum Hall effect is generalized to higher fractions. N-particle model interaction is used and the gap is expressed through n-particles wave function. The excitation spectrum in general and the mean field critical behaviour are determined. The Hall conductivity is calculated from first principles. (author)

  13. Dynamics Of Human Motion The Case Study of an Examination Hall

    Science.gov (United States)

    Ogunjo, Samuel; Ajayi, Oluwaseyi; Fuwape, Ibiyinka; Dansu, Emmanuel

    Human behaviour is difficult to characterize and generalize due to ITS complex nature. Advances in mathematical models have enabled human systems such as love interaction, alcohol abuse, admission problem to be described using models. This study investigates one of such problems, the dynamics of human motion in an examination hall with limited computer systems such that students write their examination in batches. The examination is characterized by time (t) allocated to each students and difficulty level (dl) associated with the examination. A stochastic model based on the difficulty level of the examination was developed for the prediction of student's motion around the examination hall. A good agreement was obtained between theoretical predictions and numerical simulation. The result obtained will help in better planning of examination session to maximize available resources. Furthermore, results obtained in the research can be extended to other areas such as banking hall, customer service points where available resources will be shared amongst many users.

  14. The effect of a portion size intervention on French fries consumption, plate waste, satiety and compensatory caloric intake: an on-campus restaurant experiment.

    Science.gov (United States)

    Vermote, Marie; Versele, Vickà; Stok, Marijn; Mullie, Patrick; D'Hondt, Eva; Deforche, Benedicte; Clarys, Peter; Deliens, Tom

    2018-04-13

    One of the driving factors of dietary overconsumption throughout the last decennia is the increase of food portion sizes. Larger portions induce higher daily energy intake, so reducing portion size may reduce intake of excess calories. However, real-life studies about the effects of portion size reduction are lacking. Therefore, this study examined the effect of a French fries portion size reduction on French fries consumption, French fries plate waste, satiety and caloric intake during the subsequent afternoon among university students and employees in a Belgian on-campus restaurant setting. Moreover, this study evaluated consumers' perception about the portion size reduction. The study took place over a two-time (i.e. baseline and intervention week) 4-day period (Tuesday-Friday) in the on-campus restaurant where ±1200 meals are served every day. French fries' portions were reduced by 20% by replacing the usual porcelain bowl served during the baseline week (±200 g) with smaller volume paper bags during the intervention week (±159 g) in a pre-post real-life experiment. French fries consumption and plate waste were measured in 2056 consumers at baseline and 2175 consumers at intervention. Additionally, interviews were conducted directly after lunch and again between 4 and 6 p.m. on the same day to assess satiety and caloric intake at pre and post in a small subsample of both French fries consumers (n = 19) and non-French fries consumers (n = 14). Post-intervention, the same subsample was interviewed about their perception of the portion size reduction (n = 28). Total French fries intake decreased by 9.1%, and total plate waste decreased by 66.4%. No differences were found in satiety or caloric intake between baseline and intervention week among the French fries' consumers. The majority (n = 24, 86%) of French fries consumers noticed the reduction in portion size during the intervention. Although most participants (n = 19, 68%) perceived the

  15. Report of experimental hall subworking group

    International Nuclear Information System (INIS)

    Miyake, K.; Ohama, T.; Takahashi, K.

    1982-01-01

    The general plan of constructing the TRISTAN e + e - colliding beam experimental halls may be divided into two parts. The first step is to construct two test-experimental halls associated with the 6.5 GeV x 6.5 GeV e + e - accumulator ring, and the second step is to build four experimental halls at the 30 GeV x 30 GeV e + e - TRISTAN main ring. At this workshop, extensive discussions on the detailed design of the four main ring experimental halls have been made. Four experimental areas will be built at the main ring, and two test-experimental halls at the accumulating ring. Among the four areas at the main ring, two will be used for electron-proton possible as well as electron-positron colliding beam experiment. The other two will be used exclusively for e + e - colliding experiments. Only a preliminary design has been made for these four experimental areas. A tentative plan of a larger experimental hall includes a counting and data processing room, a utility room, and a radiation safety control room. Two smaller halls have simpler structure. The figures of the experimental halls are presented. The two test-experimental halls at the accumulator ring will be used to test the detectors for e + e - colliding experiments before the final installation. The utility rooms designed for the halls are used to supply coolant and electric power of superconducting magnets. At the workshop, various ideas concerning the preliminary plan are presented. (Kato, T.)

  16. The quantum Hall effect helicity

    Energy Technology Data Exchange (ETDEWEB)

    Shrivastava, Keshav N., E-mail: keshav1001@yahoo.com [Department of Physics, University of Malaya, Kuala Lumpur 50603 (Malaysia); School of Physics, University of Hyderabad, Hyderabad 500046 (India)

    2015-04-16

    The quantum Hall effect in semiconductor heterostructures is explained by two signs in the angular momentum j=l±s and g=(2j+1)/(2l+1) along with the Landau factor (n+1/2). These modifications in the existing theories explain all of the fractional charges. The helicity which is the sign of the product of the linear momentum with the spin p.s plays an important role for the understanding of the data at high magnetic fields. In particular it is found that particles with positive sign in the spin move in one direction and those with negative sign move in another direction which explains the up and down stream motion of the particles.

  17. Stuart Hall: An Organic Intellectual

    Directory of Open Access Journals (Sweden)

    Johanna Fernández Castro

    2017-01-01

    Full Text Available Stuart Hall (3 February 1932 – 10 February 2014 is acknowledged as one of the founding figures of British Cultural Studies. His extensive academic work on topics such as race, ethnicity and identity reflects his own position as a diasporic intellectual. His contribution to the study of popular culture is determined by the importance of his political character in every social act, his non-deterministic view of Marxism, and is especially determined by his insistence on playing an active role beyond academia in order to contribute to the transformation of hegemonic structures. The following biography aims to give a focused view of his personal history and its direct influence on his key theoretical reflections.

  18. The fractional quantum Hall effect

    International Nuclear Information System (INIS)

    Stormer, H.L.

    1988-01-01

    The fractional quantum Hall effect (FQHE), is the manifestation of a new, highly correlated, many-particle ground state that forms in a two-dimensional electron system at low temperatures and in high magnetic fields. It is an example of the new physics that has grown out of the tremendous recent advances in semiconductor material science, which has provided us with high-quality, lower-dimensional carrier systems. The novel electronic state exposes itself in transport experiments through quantization of the Hall resistance to an exact rational fraction of h/e, and concomitantly vanishing longitudinal resistivity. Its relevant energy scale is only a few degrees kelvin. The quantization is a consequence of the spontaneous formation of an energy gap separating the condensed ground state from its rather elusive quasiparticle excitations. The theoretical understanding of the novel quantum liquids which underlie the FQHE has predominantly emerged from an ingenious many-particle wave function strongly supported by numerous few-particle simulations. Theory has now constructed a complex model for ideal two-dimensional electron systems in the presence of high magnetic fields and makes definitive, often fascinating predictions. Experiments have successively uncovered odd-denominator fractional states reaching presently to 7/13. The application of new experimental tools to the FQHE, such as optics, microwaves, and phonon techniques promises the direct observation of such parameters as the gap energy and possibly even some of the more elusive quantities in the future. While theory and experiment in the FQHE appear to be converging, there remains considerable room for challenging surprises. This paper provides a concise overview of the FQHE. It focuses on the experimental aspects and states, but does not expand on the theoretical advances. 70 refs., 11 figs

  19. Feasibility Analysis of Improving On-Campus Learning Paths via a Depth Sensor

    Science.gov (United States)

    Pan, Wen-Fu; Tu, Shih-Chun; Chien, Mei-Ying

    2014-01-01

    This research aims to apply a depth sensor to create a human-body-sensing context for outdoor learning paths; it is conducted by incorporating both quasi-experiment and survey to compare students' cognitive learning outcome within the context and understand students' attitudes toward the context created. The result of ANCOVA indicates that the…

  20. Credit Cards on Campus: Academic Inquiry, Objective Empiricism, or Advocacy Research?

    Science.gov (United States)

    Manning, Robert D.; Kirshak, Ray

    2005-01-01

    Professors John M. Barron and Michael E. Staten's article in Vol. 34, No. 3 of this journal, "Usage of Credit Cards Received through College Student-Marketing Programs," purports to "provide benchmark measures of college student credit card usage." Based on empirical analyses of proprietary industry data, they conclude that "There is no…

  1. Socialization in the Institution: A Working Group's Journey to Bring Public Engagement into Focus on Campus

    Science.gov (United States)

    Plakans, Lia; Alper, Rebecca; Colvin, Carolyn; Aquilino, Mary; Louko, Linda J.; Zebrowski, Patricia; Ali, Saba Rasheed

    2016-01-01

    For over 3 years, 6 faculty members and 1 graduate student have gathered as a working group applying an interdisciplinary focus to public engagement projects involving immigrant families in the rural Midwest. One dimension of the group's effort has been to involve faculty, staff, and students from many disciplines in its examination of pertinent…

  2. The quantum Hall effects: Philosophical approach

    Science.gov (United States)

    Lederer, P.

    2015-05-01

    The Quantum Hall Effects offer a rich variety of theoretical and experimental advances. They provide interesting insights on such topics as gauge invariance, strong interactions in Condensed Matter physics, emergence of new paradigms. This paper focuses on some related philosophical questions. Various brands of positivism or agnosticism are confronted with the physics of the Quantum Hall Effects. Hacking's views on Scientific Realism, Chalmers' on Non-Figurative Realism are discussed. It is argued that the difficulties with those versions of realism may be resolved within a dialectical materialist approach. The latter is argued to provide a rational approach to the phenomena, theory and ontology of the Quantum Hall Effects.

  3. Quantized Hall conductance as a topological invariant

    International Nuclear Information System (INIS)

    Niu, Q.; Thouless, Ds.J.; Wu, Y.S.

    1984-10-01

    Whenever the Fermi level lies in a gap (or mobility gap) the bulk Hall conductance can be expressed in a topologically invariant form showing the quantization explicitly. The new formulation generalizes the earlier result by TKNN to the situation where many body interaction and substrate disorder are also present. When applying to the fractional quantized Hall effect we draw the conclusion that there must be a symmetry breaking in the many body ground state. The possibility of writing the fractionally quantized Hall conductance as a topological invariant is also carefully discussed. 19 references

  4. Piezo Voltage Controlled Planar Hall Effect Devices.

    Science.gov (United States)

    Zhang, Bao; Meng, Kang-Kang; Yang, Mei-Yin; Edmonds, K W; Zhang, Hao; Cai, Kai-Ming; Sheng, Yu; Zhang, Nan; Ji, Yang; Zhao, Jian-Hua; Zheng, Hou-Zhi; Wang, Kai-You

    2016-06-22

    The electrical control of the magnetization switching in ferromagnets is highly desired for future spintronic applications. Here we report on hybrid piezoelectric (PZT)/ferromagnetic (Co2FeAl) devices in which the planar Hall voltage in the ferromagnetic layer is tuned solely by piezo voltages. The change of planar Hall voltage is associated with magnetization switching through 90° in the plane under piezo voltages. Room temperature magnetic NOT and NOR gates are demonstrated based on the piezo voltage controlled Co2FeAl planar Hall effect devices without the external magnetic field. Our demonstration may lead to the realization of both information storage and processing using ferromagnetic materials.

  5. Contribution of the study of the Hall Effect. Hall Effect of powder products

    International Nuclear Information System (INIS)

    Cherville, Jean

    1961-01-01

    This research thesis reports the development of an apparatus aimed at measuring the Hall Effect and the magneto-resistance of powders at room temperature and at the liquid nitrogen temperature. The author also proposes a theoretical contribution to the Hall Effect and reports the calculation of conditions to be met to obtain a correct value for the Hall constant. Results are experimentally verified. The method is then applied to the study of a set of powdered pre-graphitic graphites. The author shows that their Hall coefficient confirms the model already proposed by Mrozowski. The study of the Hall Effect of any kind of powders can thus be performed, and the Hall Effect can therefore be a mean to study mineral and organic compounds, and notably powdered biological molecules [fr

  6. The infrared Hall effect in YBCO: Temperature and frequency dependence of Hall scattering

    International Nuclear Information System (INIS)

    Grayson, M.; Cerne, J.; Drew, H.D.; Schmadel, D.C.; Hughes, R.; Preston, J.S.; Kung, P.J.; Vale, L.

    1999-01-01

    The authors measure the Hall angle, θ H , in YBCO films in the far- and mid-infrared to determine the temperature and frequency dependence of the Hall scattering. Using novel modulation techniques they measure both the Faraday rotation and ellipticity induced by these films in high magnetic fields to deduce the complex conductivity tensor. They observe a strong temperature dependence of the mid-infrared Hall conductivity in sharp contrast to the weak dependence of the longitudinal conductivity. By fitting the frequency dependent normal state Hall angle to a Lorentzian θ H (ω) = ω H /(γ H minus iω) they find the Hall frequency, ω H , is nearly independent of temperature. The Hall scattering rate, γ H , is consistent with γ H ∼ T 2 up to 200 K and is remarkably independent of IR frequency suggesting non-Fermi liquid behavior

  7. College Student for a Day: A Transition Program for High School Students with Disabilities

    Science.gov (United States)

    Novakovic, Alexandra; Ross, Denise E.

    2015-01-01

    High school students with disabilities can benefit from early exposure to campus-based accommodations and supports as they transition to college. College Student for a Day (CSFAD) is an on-campus activity-based program that introduces high school students with disabilities to supports and accommodations on a college campus. This Practice Brief…

  8. With Educational Benefits for All: Campus Inclusion through Learning Communities Designed for Underserved Student Populations

    Science.gov (United States)

    Fink, John E.; Hummel, Mary L.

    2015-01-01

    This chapter explores the practices of learning communities designed for specific, underserved student populations, highlighting on-campus examples and culminating with a synthesized list of core practices from these "inclusive" learning communities.

  9. Topologically induced fractional Hall steps in the integer quantum Hall regime of MoS 2

    Science.gov (United States)

    Firoz Islam, SK; Benjamin, Colin

    2016-09-01

    The quantum magnetotransport properties of a monolayer of molybdenum disulfide are derived using linear response theory. In particular, the effect of topological terms on longitudinal and Hall conductivity is analyzed. The Hall conductivity exhibits fractional steps in the integer quantum Hall regime. Further complete spin and valley polarization of the longitudinal conductivitity is seen in presence of these topological terms. Finally, the Shubnikov-de Hass oscillations are suppressed or enhanced contingent on the sign of these topological terms.

  10. Research and Mass Deployment of Non-cognitive Authentication Strategy Based on Campus Wireless Network

    Directory of Open Access Journals (Sweden)

    Huangfu Dapeng

    2018-01-01

    Full Text Available With the rapid development of Internet +, the dependence on wireless networks and wireless terminals are increasing. Campus wireless network has become the main network of teachers and students in campus on the internet. As there are uneven clients and a wide variety of intelligent terminals now. Simplified authentication and network security become the most urgent problem for wireless network. This paper used the Portal + Mac authentication method to realize the non-cognitive authentication of teachers and students on basis of the analysis of the advantages and disadvantages of mainstream authentication of campus wireless network, such as 802.1X authentication, Portal authentication, Mac authentication and DHCP authentication. Teachers and students only need portal certification at the first time, then surf the internet with non-perceived authentication at the second time and later. This method increases network security, and is better to meet the needs of teachers and students.

  11. Spin Hall effect by surface roughness

    KAUST Repository

    Zhou, Lingjun; Grigoryan, Vahram L.; Maekawa, Sadamichi; Wang, Xuhui; Xiao, Jiang

    2015-01-01

    induced by surface roughness subscribes only to the side-jump contribution but not the skew scattering. The paradigm proposed in this paper provides the second, not if only, alternative to generate a sizable spin Hall effect.

  12. Mesoscopic effects in the quantum Hall regime

    Indian Academy of Sciences (India)

    . When band mixing between multiple Landau levels is present, mesoscopic effects cause a crossover from a sequence of quantum Hall transitions for weak disorder to classical behavior for strong disorder. This behavior may be of relevance ...

  13. Plasmon Geometric Phase and Plasmon Hall Shift

    Science.gov (United States)

    Shi, Li-kun; Song, Justin C. W.

    2018-04-01

    The collective plasmonic modes of a metal comprise a simple pattern of oscillating charge density that yields enhanced light-matter interaction. Here we unveil that beneath this familiar facade plasmons possess a hidden internal structure that fundamentally alters its dynamics. In particular, we find that metals with nonzero Hall conductivity host plasmons with an intricate current density configuration that sharply departs from that of ordinary zero Hall conductivity metals. This nontrivial internal structure dramatically enriches the dynamics of plasmon propagation, enabling plasmon wave packets to acquire geometric phases as they scatter. At boundaries, these phases accumulate allowing plasmon waves that reflect off to experience a nonreciprocal parallel shift. This plasmon Hall shift, tunable by Hall conductivity as well as plasmon wavelength, displaces the incident and reflected plasmon trajectories and can be readily probed by near-field photonics techniques. Anomalous plasmon geometric phases dramatically enrich the nanophotonics toolbox, and yield radical new means for directing plasmonic beams.

  14. A system for pulse Hall effect measurements

    International Nuclear Information System (INIS)

    Orzechowski, T.; Kupczak, R.

    1975-01-01

    Measuring system for fast Hall-voltage changes in an n-type germanium sample irradiated at liquid nitrogen temperature with a high-energy electron-beam from the Van de Graaff accelerator is described. (author)

  15. Novel optical probe for quantum Hall system

    Indian Academy of Sciences (India)

    to explore Landau levels of a two-dimensional electron gas (2DEG) in modulation doped ... Keywords. Surface photovoltage spectroscopy; quantum Hall effect; Landau levels; edge states. ... An optical fibre carries light from tunable diode laser.

  16. AA under construction in its hall

    CERN Multimedia

    CERN PhotoLab

    1980-01-01

    The Antiproton Accumulator was installed in a specially built hall. Here we see it at an "early" stage of installation, just a few magnets on the floor, no vacuum chamber at all, but: 3 months later there was circulating beam !

  17. Elementary theory of quantum Hall effect

    Directory of Open Access Journals (Sweden)

    Keshav N. Shrivastava

    2008-04-01

    Full Text Available The Hall effect is the generation of a current perpendicular to both the direction of the applied electric as well as magnetic field in a metal or in a semiconductor. It is used to determine the concentration of electrons. The quantum Hall effect with integer quantization was discovered by von Klitzing and fractionally charged states were found by Tsui, Stormer and Gossard. Robert Laughlin explained the quantization of Hall current by using “flux quantization” and introduced incompressibility to obtain the fractional charge. We have developed the theory of the quantum Hall effect by using the theory of angular momentum. Our predicted fractions are in accord with those measured. We emphasize our explanation of the observed phenomena. We use spin to explain the fractional charge and hence we discover spin-charge locking.

  18. The fluctuation Hall conductivity and the Hall angle in type-II superconductor under magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Tinh, Bui Duc, E-mail: tinhbd@hnue.edu.vn [Institute of Research and Development, Duy Tan University, K7/25 Quang Trung, Danang (Viet Nam); Department of Physics, Hanoi National University of Education, 136 Xuan Thuy, Cau Giay, Hanoi (Viet Nam); Hoc, Nguyen Quang; Thu, Le Minh [Department of Physics, Hanoi National University of Education, 136 Xuan Thuy, Cau Giay, Hanoi (Viet Nam)

    2016-02-15

    Highlights: • The time-dependent Ginzburg–Landau was used to calculate fluctuation Hall conductivity and Hall angle in type-II superconductor in 2D and 3D. • We obtain analytical expressions for the fluctuation Hall conductivity and the Hall angle summing all Landau levels without need to cutoff higher Landau levels to treat arbitrary magnetic field. • The results were compared to the experimental data on YBCO. - Abstract: The fluctuation Hall conductivity and the Hall angle, describing the Hall effect, are calculated for arbitrary value of the imaginary part of the relaxation time in the frame of the time-dependent Ginzburg–Landau theory in type II-superconductor with thermal noise describing strong thermal fluctuations. The self-consistent Gaussian approximation is used to treat the nonlinear interaction term in dynamics. We obtain analytical expressions for the fluctuation Hall conductivity and the Hall angle summing all Landau levels without need to cutoff higher Landau levels to treat arbitrary magnetic field. The results are compared with experimental data on high-T{sub c} superconductor.

  19. NAS Decadal Review Town Hall

    Science.gov (United States)

    The National Academies of Sciences, Engineering and Medicine is seeking community input for a study on the future of materials research (MR). Frontiers of Materials Research: A Decadal Survey will look at defining the frontiers of materials research ranging from traditional materials science and engineering to condensed matter physics. Please join members of the study committee for a town hall to discuss future directions for materials research in the United States in the context of worldwide efforts. In particular, input on the following topics will be of great value: progress, achievements, and principal changes in the R&D landscape over the past decade; identification of key MR areas that have major scientific gaps or offer promising investment opportunities from 2020-2030; and the challenges that MR may face over the next decade and how those challenges might be addressed. This study was requested by the Department of Energy and the National Science Foundation. The National Academies will issue a report in 2018 that will offer guidance to federal agencies that support materials research, science policymakers, and researchers in materials research and other adjoining fields. Learn more about the study at http://nas.edu/materials.

  20. Resistive Instabilities in Hall Current Plasma Discharge

    International Nuclear Information System (INIS)

    Litvak, Andrei A.; Fisch, Nathaniel J.

    2000-01-01

    Plasma perturbations in the acceleration channel of a Hall thruster are found to be unstable in the presence of collisions. Both electrostatic lower-hybrid waves and electromagnetic Alfven waves transverse to the applied electric and magnetic field are found to be unstable due to collisions in the E X B electron flow. These results are obtained assuming a two-fluid hydrodynamic model in slab geometry. The characteristic frequencies of these modes are consistent with experimental observations in Hall current plasma thrusters

  1. Are tent halls subject to property tax?

    Directory of Open Access Journals (Sweden)

    Mariusz Macudziński

    2016-12-01

    Full Text Available The presented publication is a response to currently asked questions and interpretative doubts of taxpayers and tax authorities, namely whether tent halls are subject to property tax. General issues connected with an entity and a subject of taxation of this tax are presented herein. The answer to the question asked is then provided through the qualification of constructions works and the allocation of tent halls in the proper category of the works, with the use of the current law.

  2. Fractional statistics and fractional quantized Hall effect

    International Nuclear Information System (INIS)

    Tao, R.; Wu, Y.S.

    1985-01-01

    The authors suggest that the origin of the odd-denominator rule observed in the fractional quantized Hall effect (FQHE) may lie in fractional statistics which govern quasiparticles in FQHE. A theorem concerning statistics of clusters of quasiparticles implies that fractional statistics do not allow coexistence of a large number of quasiparticles at fillings with an even denominator. Thus, no Hall plateau can be formed at these fillings, regardless of the presence of an energy gap. 15 references

  3. Hall effect in organic layered conductors

    Directory of Open Access Journals (Sweden)

    R.A.Hasan

    2006-01-01

    Full Text Available The Hall effect in organic layered conductors with a multisheeted Fermi surfaces was considered. It is shown that the experimental study of Hall effect and magnetoresistance anisotropy at different orientations of current and a quantizing magnetic field relative to the layers makes it possible to determine the contribution of various charge carriers groups to the conductivity, and to find out the character of Fermi surface anisotropy in the plane of layers.

  4. Sexual Violence on Campus: Differences Across Gender and Sexual Minority Status.

    Science.gov (United States)

    Martin-Storey, Alexa; Paquette, Geneviève; Bergeron, Manon; Dion, Jacinthe; Daigneault, Isabelle; Hébert, Martine; Ricci, Sandrine

    2018-06-01

    Sexual violence is a pervasive problem on university campuses. Although previous work has documented greater vulnerability for sexual violence among sexual and gender minority students, little is known about contextual variation in vulnerability to this kind of violence. The goals of the current study were (1) to identify vulnerability among sexual and gender minority students with regard to sexual violence, and (2) to explore if the context of this violence differs across sexual and gender minority status. Undergraduate students (ages 18-24) from six francophone universities in Quebec, Canada (N = 4,264) completed online questionnaires regarding their experience of sexual violence, as well as the context of these acts (e.g., the gender of the perpetrator, the status of the perpetrator, and the location of the violence). They also provided information regarding their sexual and gender minority status. Binary logistic regressions were conducted to assess for variation in experiencing sexual violence across sexual and gender minority status. Transgender/nonbinary students generally reported higher levels of sexual violence than their cisgender peers, while variation occurred with regard to vulnerability across sexual identity subgroups. Few differences in context were observed across sexual minority identity. Transgender/nonbinary students were significantly more likely to report sexual violence in athletic contexts and during volunteering activities compared to their cisgender peers. Findings highlight the higher levels of vulnerability for sexual violence among gender minority and some sexual minority university students. They also point to the contexts in which such violence occurs, suggesting specific strategies for prevention. Copyright © 2018 The Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  5. Perceptions about Residence Hall Wingmates and Alcohol-Related Secondhand Effects among College Freshmen

    Science.gov (United States)

    Boekeloo, Bradley O.; Bush, Elizabeth N.; Novik, Melinda G.

    2009-01-01

    Objective: The authors examined the secondhand effects among college freshmen of others' alcohol use and related student characteristics, and perceptions about residence hallmates. Participants: The authors surveyed 509 incoming freshmen residing in predominantly freshman residence halls. Methods: The authors administered a Web-based survey 2…

  6. Prentice Hall/Pearson Literature© (2007-15). What Works Clearinghouse Intervention Report

    Science.gov (United States)

    What Works Clearinghouse, 2017

    2017-01-01

    "Prentice Hall/Pearson Literature©" (2007-15) is an English language arts curriculum designed for students in grades 6-12 that focuses on building reading, vocabulary, literary analysis, and writing skills. It uses passages from fiction and nonfiction texts, poetry, and contemporary digital media. The curriculum is based on a textbook.…

  7. Raising the Bar: Standards and Tests in California's High Schools. A Town Hall Meeting.

    Science.gov (United States)

    Arnstine, Barbara; Futernick, Ken; Hodson, Timothy A.; Ostgaard, Kolleen

    In 1999, the LegiSchool Project planned to conduct the 12th in its series of televised Town Hall Meetings to provide a forum in which California high school students, educators, and legislators can engage in face-to-face dialogue about problems of mutual interest. For 1999, the topic is standards and tests in California high schools. This guide…

  8. Elon Musk, founder of SpaceX and PayPal, to speak on campus Feb. 21

    OpenAIRE

    Crumbley, Liz

    2006-01-01

    Elon Musk, founder and chief executive officer of Space Exploration Technologies Co. (SpaceX), will speak on his company's Falcon rocket series and the future of university space research on Tuesday, Feb. 21 at 7:30 p.m. in Virginia Tech's Burruss Hall Auditorium. The event is free and open to the public.

  9. Mhealth on Campus: Assessing Undergraduates' Attitudes and Utilization of Mobile Health Applications

    Science.gov (United States)

    Haithcox-Dennis, Melissa; Brinkley, Jason; Richman, Alice; DeWeese, Amanda; Byrd, James L., III

    2012-01-01

    Mhealth is rapidly becoming a valuable tool to increase knowledge and skills that contribute to healthy behaviors. Currently, little is known about college students' ownership and use of health apps. The primary purpose of this study was to investigate undergraduates' mhealth app usage and views. A secondary purpose was to identify any subgroup…

  10. Service and Emotional Support Animals on Campus: The Relevance and Controversy

    Science.gov (United States)

    Phillips, Melinda

    2016-01-01

    Service and emotional support animals (ESA) have recently been a topic of conversation on college campuses, despite decades of controversy related to the interpretation of federal law. The distinction between an Emotional Support Animal and Service Animals, and the rights of the student regarding accommodations under FHA and ADA have been debated…

  11. Crisis on Campus: Eating Disorder Intervention from a Developmental-Ecological Perspective

    Science.gov (United States)

    Taylor, Julia V.; Gibson, Donna M.

    2016-01-01

    Objective: The purpose of this article is to review a crisis intervention using the developmental-ecological protocol (Collins and Collins, 2005) with a college student presenting with symptomatology of an active eating disorder. Participants: Participants included University Wellness Center employees responding to the crisis. Methods: Methods…

  12. Instructor Strategies for Responding to Disclosures of Gender-Based Violence on Campus

    Science.gov (United States)

    Root, Jennifer L.; Godderis, Rebecca

    2016-01-01

    While increasing attention has been paid to the issue of sexual violence (SV) on university and college campuses, there is a paucity of research about how post-secondary instructors should respond to student disclosures of SV and other forms of gender-based violence (GBV). The limited amount of evidence suggests instructors who receive disclosures…

  13. Academic Beliefs and Behaviors in On-Campus and Online General Education Biology Classes

    Science.gov (United States)

    Noll, Christopher B.

    2015-01-01

    This study examined the effect of course delivery mode on academic help-seeking beliefs and behaviors, academic self-efficacy, and the levels of individual interest in biology of students in an entry-level General Education biology course. This intersection of online education, science courses, and academic success factors merits attention because…

  14. Crime on Campus: Institutional Tort Liability for the Criminal Acts of Third Parties.

    Science.gov (United States)

    Raddatz, Anita

    To aid colleges and universities in protecting students and other potential victims of crime, a general analysis of the pertinent case law concerning institutional tort liability for campus crime is provided. The analysis of case law explains that lawsuits are usually based on the theory of negligence. Negligence consists of four elements: duty;…

  15. Evaluation of Scalable Applications of Information Technology to On-Campus Learning.

    Science.gov (United States)

    Matthews, Harry R.; Sommer, Barbara; Maher, Michael; Acredolo, Curt; Ho, Arnold; Falk, Richard

    The University of California, Davis, is transforming large general education courses in a cost-effective way that maintains high academic standards in the face of rising student enrollments. Two multi-year pilot projects have demonstrated the feasibility of using rich online learning environments to reduce the dependence on formal lectures. This…

  16. Lessons Learned: Creating an Online Business Degree from a Successful On-Campus Business Degree

    Science.gov (United States)

    Cordeiro, William P.; Muraoka, Dennis

    2015-01-01

    The horse has left the barn. Distance education is here to stay and the number of degree programs offered online is growing rapidly. California State University Channel Islands (CI) admitted its first students in 2002, and the undergraduate and graduate degrees in business were among its first program offerings. From its inception, the…

  17. Australian and International Student Success Rates in Group of Eight Universities. Go8 Backgrounder 5

    Science.gov (United States)

    Group of Eight (NJ1), 2008

    2008-01-01

    This Go8 Backgrounder compares the academic performance of three cohorts of students in Group of Eight (Go8) universities: Australian students, international students on campus in Australia (onshore) and international students overseas (offshore). Analysis of data supplied by Go8 universities shows that in 2007 students passed 91.8% of the courses…

  18. Lifelong Learning at the Technion: Graduate Students' Perceptions of and Experiences in Distance Learning

    Science.gov (United States)

    Hussein-Farraj, Rania; Barak, Miri; Dori, Yehudit Judy

    2012-01-01

    This study examined the development of two Distance Learning (DL) courses and their effect on students' perceptions and learning experiences. Our study included about 260 science and engineering graduate students. Among them, 105 students were divided into two research groups: on-campus students (N=70) and DL students (N=35). These two groups…

  19. 75 FR 22770 - Gary E. Hall and Rita Hall; Notice of Availability of Environmental Assessment

    Science.gov (United States)

    2010-04-30

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 13652-000-Montana] Gary E. Hall and Rita Hall; Notice of Availability of Environmental Assessment April 22, 2010. In accordance with the National Environmental Policy Act of 1969, as amended, and the Federal Energy Regulatory...

  20. Surveys of Students Challenge "Helicopter Parent" Stereotypes

    Science.gov (United States)

    Hoover, Eric

    2008-01-01

    Stories of "helicopter parents" abound. But several longtime student-affairs officials agree that while helicopter parents are real, their numbers--and behaviors--have been exaggerated. Parental involvement on campus, they say, is usually more of a help than a headache, for students and colleges alike. Some officials believe colleges must do even…

  1. LGBTQ+ Young Adults on the Street and on Campus: Identity as a Product of Social Context.

    Science.gov (United States)

    Schmitz, Rachel M; Tyler, Kimberly A

    2018-01-01

    Lesbian, gay, bisexual, queer, and other sexual and gender minority (LGBTQ+) young adults face unique identity-related experiences based on their immersion in distinctive social contexts. The predominant framework of performing separate analyses on samples of LGBTQ+ young people by their primary social status obfuscates more holistic understandings of the role of social context. Using 46 in-depth interviews with LGBTQ+ college students and LGBTQ+ homeless young adults, we ask: How are LGBTQ+ young adults' capacities for "doing" their gender and sexual identities shaped by their distinctive social contexts? In developing their identities, both groups of LGBTQ+ young adults navigated their social environments to seek out resources and support. Most college students described their educational contexts as conducive to helping them develop their identities, or "undo" rigid norms of gender and sexuality. Homeless young adults' social environments, meanwhile, imposed complex barriers to self-expression that reinforced more normative expectations of "doing" gender and sexual identities.

  2. Charge carrier coherence and Hall effect in organic semiconductors

    Science.gov (United States)

    Yi, H. T.; Gartstein, Y. N.; Podzorov, V.

    2016-01-01

    Hall effect measurements are important for elucidating the fundamental charge transport mechanisms and intrinsic mobility in organic semiconductors. However, Hall effect studies frequently reveal an unconventional behavior that cannot be readily explained with the simple band-semiconductor Hall effect model. Here, we develop an analytical model of Hall effect in organic field-effect transistors in a regime of coexisting band and hopping carriers. The model, which is supported by the experiments, is based on a partial Hall voltage compensation effect, occurring because hopping carriers respond to the transverse Hall electric field and drift in the direction opposite to the Lorentz force acting on band carriers. We show that this can lead in particular to an underdeveloped Hall effect observed in organic semiconductors with substantial off-diagonal thermal disorder. Our model captures the main features of Hall effect in a variety of organic semiconductors and provides an analytical description of Hall mobility, carrier density and carrier coherence factor. PMID:27025354

  3. Charge carrier coherence and Hall effect in organic semiconductors.

    Science.gov (United States)

    Yi, H T; Gartstein, Y N; Podzorov, V

    2016-03-30

    Hall effect measurements are important for elucidating the fundamental charge transport mechanisms and intrinsic mobility in organic semiconductors. However, Hall effect studies frequently reveal an unconventional behavior that cannot be readily explained with the simple band-semiconductor Hall effect model. Here, we develop an analytical model of Hall effect in organic field-effect transistors in a regime of coexisting band and hopping carriers. The model, which is supported by the experiments, is based on a partial Hall voltage compensation effect, occurring because hopping carriers respond to the transverse Hall electric field and drift in the direction opposite to the Lorentz force acting on band carriers. We show that this can lead in particular to an underdeveloped Hall effect observed in organic semiconductors with substantial off-diagonal thermal disorder. Our model captures the main features of Hall effect in a variety of organic semiconductors and provides an analytical description of Hall mobility, carrier density and carrier coherence factor.

  4. Dr. Hall and the work cure.

    Science.gov (United States)

    Reed, Kathlyn L

    2005-01-01

    Herbert James Hall, MD (1870-1923), was a pioneer in the systematic and organized study of occupation as therapy for persons with nervous and mental disorders that he called the "work cure." He began his work in 1904 during the early years of the Arts and Crafts Movement in the United States. His primary interest was the disorder neurasthenia, a condition with many symptoms including chronic fatigue, stress, and inability to work or perform everyday tasks. The prevailing treatment of the day was absolute bed rest known as the "rest cure." Hall believed that neurasthenia was not caused by overwork but by faulty living habits that could be corrected through an ordered life schedule and selected occupations. He identified several principles of therapy that are still used today including graded activity and energy conservation. Dr. Adolph Meyer credits Hall for organizing the ideas on the therapeutic use of occupation (Meyer, 1922). Hall also provided the name American Occupational Therapy Association for the professional organization and served as the fourth president. For his many contributions to the profession Hall deserves to be recognized as a major contributor to the development and organization of occupational therapy.

  5. A new CMOS Hall angular position sensor

    Energy Technology Data Exchange (ETDEWEB)

    Popovic, R.S.; Drljaca, P. [Swiss Federal Inst. of Tech., Lausanne (Switzerland); Schott, C.; Racz, R. [SENTRON AG, Zug (Switzerland)

    2001-06-01

    The new angular position sensor consists of a combination of a permanent magnet attached to a shaft and of a two-axis magnetic sensor. The permanent magnet produces a magnetic field parallel with the magnetic sensor plane. As the shaft rotates, the magnetic field also rotates. The magnetic sensor is an integrated combination of a CMOS Hall integrated circuit and a thin ferromagnetic disk. The CMOS part of the system contains two or more conventional Hall devices positioned under the periphery of the disk. The ferromagnetic disk converts locally a magnetic field parallel with the chip surface into a field perpendicular to the chip surface. Therefore, a conventional Hall element can detect an external magnetic field parallel with the chip surface. As the direction of the external magnetic field rotates in the chip plane, the output voltage of the Hall element varies as the cosine of the rotation angle. By placing the Hall elements at the appropriate places under the disk periphery, we may obtain the cosine signals shifted by 90 , 120 , or by any other angle. (orig.)

  6. Composite fermions in the quantum Hall effect

    International Nuclear Information System (INIS)

    Johnson, B.L.; Kirczenow, G.

    1997-01-01

    The quantum Hall effect and associated quantum transport phenomena in low-dimensional systems have been the focus of much attention for more than a decade. Recent theoretical development of interesting quasiparticles - 'composite fermions' - has led to significant advances in understanding and predicting the behaviour of two-dimensional electron systems under high transverse magnetic fields. Composite fermions may be viewed as fermions carrying attached (fictitious) magnetic flux. Here we review models of the integer and fractional quantum Hall effects, including the development of a unified picture of the integer and fractional effects based upon composite fermions. The composite fermion picture predicts remarkable new physics: the formation of a Fermi surface at high magnetic fields, and anomalous ballistic transport, thermopower, and surface acoustic wave behaviour. The specific theoretical predictions of the model, as well as the body of experimental evidence for these phenomena are reviewed. We also review recent edge-state models for magnetotransport in low-dimensional devices based on the composite fermion picture. These models explain the fractional quantum Hall effect and transport phenomena in nanoscale devices in a unified framework that also includes edge state models of the integer quantum Hall effect. The features of the composite fermion edge-state model are compared and contrasted with those of other recent edge-state models of the fractional quantum Hall effect. (author)

  7. Air temperature gradient in large industrial hall

    Science.gov (United States)

    Karpuk, Michał; Pełech, Aleksander; Przydróżny, Edward; Walaszczyk, Juliusz; Szczęśniak, Sylwia

    2017-11-01

    In the rooms with dominant sensible heat load, volume airflow depends on many factors incl. pre-established temperature difference between exhaust and supply airflow. As the temperature difference is getting higher, airflow volume drops down, consequently, the cost of AHU is reduced. In high industrial halls with air exhaust grids located under the ceiling additional temperature gradient above working zone should be taken into consideration. In this regard, experimental research of the vertical air temperature gradient in high industrial halls were carried out for the case of mixing ventilation system The paper presents the results of air temperature distribution measurements in high technological hall (mechanically ventilated) under significant sensible heat load conditions. The supply airflow was delivered to the hall with the help of the swirl diffusers while exhaust grids were located under the hall ceiling. Basing on the air temperature distribution measurements performed on the seven pre-established levels, air temperature gradient in the area between 2.0 and 7.0 m above the floor was calculated and analysed.

  8. Field theory approach to quantum hall effect

    International Nuclear Information System (INIS)

    Cabo, A.; Chaichian, M.

    1990-07-01

    The Fradkin's formulation of statistical field theory is applied to the Coulomb interacting electron gas in a magnetic field. The electrons are confined to a plane in normal 3D-space and also interact with the physical 3D-electromagnetic field. The magnetic translation group (MTG) Ward identities are derived. Using them it is shown that the exact electron propagator is diagonalized in the basis of the wave functions of the free electron in a magnetic field whenever the MTG is unbroken. The general tensor structure of the polarization operator is obtained and used to show that the Chern-Simons action always describes the Hall effect properties of the system. A general proof of the Streda formula for the Hall conductivity is presented. It follows that the coefficient of the Chern-Simons terms in the long-wavelength approximation is exactly given by this relation. Such a formula, expressing the Hall conductivity as a simple derivative, in combination with diagonal form of the full propagator allows to obtain a simple expressions for the filling factor and the Hall conductivity. Indeed, these results, after assuming that the chemical potential lies in a gap of the density of states, lead to the conclusion that the Hall conductivity is given without corrections by σ xy = νe 2 /h where ν is the filling factor. In addition it follows that the filling factor is independent of the magnetic field if the chemical potential remains in the gap. (author). 21 ref, 1 fig

  9. Extrinsic spin Hall effect in graphene

    Science.gov (United States)

    Rappoport, Tatiana

    The intrinsic spin-orbit coupling in graphene is extremely weak, making it a promising spin conductor for spintronic devices. In addition, many applications also require the generation of spin currents in graphene. Theoretical predictions and recent experimental results suggest one can engineer the spin Hall effect in graphene by greatly enhancing the spin-orbit coupling in the vicinity of an impurity. The extrinsic spin Hall effect then results from the spin-dependent skew scattering of electrons by impurities in the presence of spin-orbit interaction. This effect can be used to efficiently convert charge currents into spin-polarized currents. I will discuss recent experimental results on spin Hall effect in graphene decorated with adatoms and metallic cluster and show that a large spin Hall effect can appear due to skew scattering. While this spin-orbit coupling is small if compared with what it is found in metals, the effect is strongly enhanced in the presence of resonant scattering, giving rise to robust spin Hall angles. I will present our single impurity scattering calculations done with exact partial-wave expansions and complement the analysis with numerical results from a novel real-space implementation of the Kubo formalism for tight-binding Hamiltonians. The author acknowledges the Brazilian agencies CNPq, CAPES, FAPERJ and INCT de Nanoestruturas de Carbono for financial support.

  10. Health dynamics in camps and on campuses: stressors and coping strategies for wellbeing among labourers and students in Cameroon

    NARCIS (Netherlands)

    Makoge, Valerie; Maat, Harro; Vaandrager, Lenneke; Koelen, Maria

    2018-01-01

    Purpose: For many people living in low-income countries, poverty implies an increased exposure to conditions that threaten health and wellbeing as well as reduced capacity to maintain health. Despite the challenging conditions caused by poverty, people may consider themselves healthy because they

  11. Science Careers and Disabled Students.

    Science.gov (United States)

    Jagoda, Sue; Cremer, Bob

    1981-01-01

    Summarizes proceedings and student experiences at the 1980 Science Career Workshop for Physically Disabled Students at the Lawrence Hall of Science (University of California). Includes a description of the key-note speaker's topics, and other workshop activities. (DS)

  12. Crisis on campus: Eating disorder intervention from a developmental-ecological perspective.

    Science.gov (United States)

    Taylor, Julia V; Gibson, Donna M

    2016-01-01

    The purpose of this article is to review a crisis intervention using the developmental-ecological protocol (Collins and Collins, 2005) with a college student presenting with symptomatology of an active eating disorder. Participants included University Wellness Center employees responding to the crisis. Methods include an informal review of the crisis intervention response and application of the ABCDE developmental-ecological crisis model. Results reported include insight into crisis intervention when university counseling and health center is not available as resources. ABCDE Developmental-ecological model recommendations for university faculty and staff are included.

  13. Promoting Mental Health Resource Use on Campus by "Trying Something New".

    Science.gov (United States)

    Champlin, Sara; Nisbett, Gwendelyn

    2018-05-01

    To design and test a persuasive health promotion campaign that aligns with the qualities of trying something new for the first time. Given that a majority of students have not previously sought/considered professional mental health assistance before, the hypothesis tested in this study asked whether a campaign that takes this into account is effective with this audience. Participants viewed an online informational message (n = 84), information message plus first-time experience banner (n = 99), or 1 of 4 full campaigns, each depicting a student story and photo about a first-time experience (moving from home [n = 48], skydiving [n = 52], acting in a play [n = 48], and exercising with personal trainer [n = 48]). Visual poster items: appeal (visually pleasing, 7 items, α = .92), support (value of poster, 5 items, α = .86) and behavioral intention items: engagement (participant seek help/pay attention, 3 items, α = .86), relevance (content as relevant, 3 items, α = .84), and judgment (judgment of others for not seeking help, 2 items, α = .87). College students (N = 380). In comparison to information-only messages, framing mental health help seeking as a first-time experience was linked with increased appeal, support, and engagement (M informationonly = 2.79 [standard deviation, SD = 1.34], M informationplusbanner = 3.25 [SD = 1.23], M fullcampaign = 4.07 [SD = 1.28], P time experiences, there were main effects on support and engagement (M train = 5.06 [SD = 1.17], M plane = 4.27 [SD = 1.28], M home = 4.59 [SD = 1.19], M play = 4.38 [SD = 1.29], P = .009 and M train = 4.50 [SD = 1.27], M plane = 3.75 [SD = 1.43], M home = 4.01 [SD = 1.49], M play = 3.84 [SD = 1.39], P = .042, respectively), with the novel experience of "working with a personal trainer" rated highest. Findings from this study have implications for the design of health promotion materials on college campuses. Specifically, campaigns that frame seeking help for mental health as a new experience

  14. My Student Body: Effects of an Internet-Based Prevention Program to Decrease Obesity among College Students

    Science.gov (United States)

    LaChausse, Robert G.

    2012-01-01

    Objective: To determine the impact of My Student Body (MSB)-Nutrition, an Internet-based obesity prevention program for college students. Participants: Three hundred and twenty ethnically diverse undergraduate students were randomly assigned to 1 of 3 conditions: MSB-Nutrition program, an on-campus weight management course, and a comparison group.…

  15. Localization in a quantum spin Hall system.

    Science.gov (United States)

    Onoda, Masaru; Avishai, Yshai; Nagaosa, Naoto

    2007-02-16

    The localization problem of electronic states in a two-dimensional quantum spin Hall system (that is, a symplectic ensemble with topological term) is studied by the transfer matrix method. The phase diagram in the plane of energy and disorder strength is exposed, and demonstrates "levitation" and "pair annihilation" of the domains of extended states analogous to that of the integer quantum Hall system. The critical exponent nu for the divergence of the localization length is estimated as nu congruent with 1.6, which is distinct from both exponents pertaining to the conventional symplectic and the unitary quantum Hall systems. Our analysis strongly suggests a different universality class related to the topology of the pertinent system.

  16. Hall probe magnetometer for SSC magnet cables

    International Nuclear Information System (INIS)

    Cross, R.W.; Goldfarb, R.B.

    1991-01-01

    The authors of this paper constructed a Hall probe magnetometer to measure the magnetization hysteresis loops of Superconducting Super Collider magnet cables. The instrument uses two Hall-effect field sensors to measure the applied field H and the magnetic induction B. Magnetization M is calculated from the difference of the two quantities. The Hall probes are centered coaxially in the bore of a superconducting solenoid with the B probe against the sample's broad surface. An alternative probe arrangement, in which M is measured directly, aligns the sample probe parallel to the field. The authors measured M as a function of H and field cycle rate both with and without a dc transport current. Flux creep as a function of current was measured from the dependence of ac loss on the cycling rate and from the decay of magnetization with time. Transport currents up to 20% of the critical current have minimal effect on magnetization and flux creep

  17. Spin Hall Effect in Doped Semiconductor Structures

    Science.gov (United States)

    Tse, Wang-Kong; Das Sarma, Sankar

    2006-03-01

    We present a microscopic theory of the extrinsic spin Hall effect based on the diagrammatic perturbation theory. Side-jump (SJ) and skew-scattering (SS) contributions are explicitly taken into account to calculate the spin Hall conductivity, and we show their effects scale as σxy^SJ/σxy^SS ˜(/τ)/ɛF, where τ being the transport relaxation time. Motivated by recent experimental work we apply our theory to n-doped and p-doped 3D and 2D GaAs structures, obtaining analytical formulas for the SJ and SS contributions. Moreover, the ratio of the spin Hall conductivity to longitudinal conductivity is found as σs/σc˜10-3-10-4, in reasonable agreement with the recent experimental results of Kato et al. [Science 306, 1910 (2004)] in n-doped 3D GaAs system.

  18. Use of multiple on-campus reactors in education and training programs

    International Nuclear Information System (INIS)

    Schlapper, G.A.

    1989-01-01

    In its undergraduate and graduate programs in nuclear engineering and health physics, Texas A ampersand M University utilizes two reactors for the training and education of students. The 5-W AGN-201 nuclear training reactor has been in use since the late 1950s, while the 1-MW TRIGA Nuclear Science Center Reactor (NSCR) was first utilized in late 1961. Both facilities have been upgraded since initial criticality, the AGN power level being increased from the original 200-mW limit to its 5-W current level and the NSCR undergoing conversion from a 100-kW materials test reactor fueled deign to a 1-MW TRIGA-fueled facility. The AGN reactor is operated by the Department of Nuclear Engineering of the College of Engineering and is almost solely utilized in training and education programs. The NSCR facility is administered by the Texas Engineering Experiment Station and support research efforts of faculty and students of departments within and outside the university in addition to contributing to the education and training programs of the nuclear engineering department

  19. Shielding consideration for the SSCL experimental halls

    International Nuclear Information System (INIS)

    Bull, J.; Coyne, J.; Mokhov, N.; Stapleton, G.

    1994-03-01

    The Superconducting Super Collider which is being designed and built in Waxahachie, Texas consists Of series of proton accelerators, culminating in a 20 Te proton on proton collider. The collider will be in a tunnel which will be 87 km in circumference and. on average about 30 meters underground. The present design calls for two large interaction halls on the east side of the ring. The shielding for these halls is being designed for an interaction rate of 10 9 Hz or 10 16 interactions per year, based on 10 7 seconds per operational year. SSC guidelines require that the shielding be designed to meet the criterion of 1mSv per year for open areas off site 2mSv per year for open areas on site, and 2mSv per year for controlled areas. Only radiation workers will be routinely allowed to work in controlled areas. It should be pointed that there is a potential for an accidental full beam loss in either of the experimental halls, and this event would consist of the loss of the full circulating beam up to 4 x 10 14 protons. With the present design. the calculated dose equivalent for this event is about 10% of the annual dose equivalent for the normal p-p interactions, so that die accident condition does not control the shielding. If, for instance, local shielding within the experimental hall is introduced into the calculations, this could change. The shielding requirements presented here are controlled by the normal p-p interactions. Three important questions were addressed in the present calculations. They are (1) the thickness of the roof over the experimental halls, (2) the configuration of the shafts and adits which give access to the halls, and (3) the problem of ground water and air activation

  20. Developments in Scanning Hall Probe Microscopy

    Science.gov (United States)

    Chouinard, Taras; Chu, Ricky; David, Nigel; Broun, David

    2009-05-01

    Low temperature scanning Hall probe microscopy is a sensitive means of imaging magnetic structures with high spatial resolution and magnetic flux sensitivity approaching that of a Superconducting Quantum Interference Device. We have developed a scanning Hall probe microscope with novel features, including highly reliable coarse positioning, in situ optimization of sensor-sample alignment and capacitive transducers for linear, long range positioning measurement. This has been motivated by the need to reposition accurately above fabricated nanostructures such as small superconducting rings. Details of the design and performance will be presented as well as recent progress towards time-resolved measurements with sub nanosecond resolution.

  1. Enhanced Performance of Cylindrical Hall Thrusters

    International Nuclear Information System (INIS)

    Raitses, Y.; Smirnov, A.; Fisch, N.J.

    2007-01-01

    The cylindrical thruster differs significantly in its underlying physical mechanisms from the conventional annular Hall thruster. It features high ionization efficiency, quiet operation, ion acceleration in a large volume-to-surface ratio channel, and performance comparable with the state-of-the-art conventional Hall thrusters. Very significant plume narrowing, accompanied by the increase of the energetic ion fraction and improvement of ion focusing, led to 50-60% increase of the thruster anode efficiency. These improvements were achieved by overrunning the discharge current in the magnetized thruster plasma

  2. Inverse spin Hall effect by spin injection

    Science.gov (United States)

    Liu, S. Y.; Horing, Norman J. M.; Lei, X. L.

    2007-09-01

    Motivated by a recent experiment [S. O. Valenzuela and M. Tinkham, Nature (London) 442, 176 (2006)], the authors present a quantitative microscopic theory to investigate the inverse spin-Hall effect with spin injection into aluminum considering both intrinsic and extrinsic spin-orbit couplings using the orthogonalized-plane-wave method. Their theoretical results are in good agreement with the experimental data. It is also clear that the magnitude of the anomalous Hall resistivity is mainly due to contributions from extrinsic skew scattering.

  3. Prototype dining hall energy efficiency study

    Energy Technology Data Exchange (ETDEWEB)

    Mazzucchi, R.P.; Bailey, S.A.; Zimmerman, P.W.

    1988-06-01

    The energy consumption of food service facilities is among the highest of any commercial building type, owing to the special requirements for food preparation, sanitation, and ventilation. Consequently, the US Air Force Engineering and Services Center (AFESC) contracted with Pacific Northwest Laboratory (PNL) to collect and analyze end-use energy consumption data for a prototypical dining hall and make specific recommendations on cost-effective energy conservation options. This information will be used to establish or update criteria for dining hall designs and retrofits as appropriate. 6 refs., 21 figs., 23 tabs.

  4. Acoustics in rock and pop music halls

    DEFF Research Database (Denmark)

    Larsen, Niels Werner; Thompson, Eric Robert; Gade, Anders Christian

    2007-01-01

    The existing body of literature regarding the acoustic design of concert halls has focused almost exclusively on classical music, although there are many more performances of rhythmic music, including rock and pop. Objective measurements were made of the acoustics of twenty rock music venues...... in Denmark and a questionnaire was used in a subjective assessment of those venues with professional rock musicians and sound engineers. Correlations between the objective and subjective results lead, among others, to a recommendation for reverberation time as a function of hall volume. Since the bass...

  5. Proton knock-out in Hall A

    International Nuclear Information System (INIS)

    Jager, K. de

    2003-01-01

    Proton knock-out is studied in a broad program in Hall A at Jefferson Lab. The first experiment performed in Hall A studied the 16 O(e,e'p) reaction. Since then proton knock-out experiments have studied a variety of aspects of that reaction, from single-nucleon properties to its mechanism, such as final-state interactions and two-body currents, in nuclei from 2 H to 16 O. In this review the accomplishments of this program will be summarized and an outlook given of expected future results. (orig.)

  6. Theory of fractional quantum Hall effect

    International Nuclear Information System (INIS)

    Kostadinov, I.Z.

    1984-09-01

    A theory of the fractional quantum Hall effect is constructed by introducing 3-particle interactions breaking the symmetry for ν=1/3 according to a degeneracy theorem proved here. An order parameter is introduced and a gap in the single particle spectrum is found. The critical temperature, critical filling number and critical behaviour are determined as well as the Ginzburg-Landau equation coefficients. A first principle calculation of the Hall current is given. 3, 5, 7 electron tunneling and Josephson interference effects are predicted. (author)

  7. Are University Co-Operative Education Students Safe? Perceptions of Risk to Students on Work Terms

    Science.gov (United States)

    Newhook, Rebecca

    2016-01-01

    As students venture off campus for university-sponsored activities, are they at risk, given that universities are better able to control risk factors on campus than they can for their off-campus activities? Co-operative education is a formalized and longstanding academic program that often sees students spend upwards of a third of their time off…

  8. The Impact of Boarding on Campus on the Social-Emotional Competence of Left-Behind Children in Rural Western China

    Science.gov (United States)

    Wang, Shutao; Dong, Xuan; Mao, Yaqing

    2017-01-01

    This study aimed to determine if boarding on campus benefited left-behind children's social-emotional competence (SEC). We developed a SEC scale for the Chinese context and culture using exploratory factor analysis, confirmatory factor analysis, and reliability analysis. Data were collected from 6638 school-aged children from 74 rural boarding…

  9. Bound values for Hall conductivity of heterogeneous medium under ...

    Indian Academy of Sciences (India)

    - ditions in inhomogeneous medium has been studied. It is shown that bound values for. Hall conductivity differ from bound values for metallic conductivity. This is due to the unusual character of current percolation under quantum Hall effect ...

  10. Performance of Distance Learning Students in a Small Business Management Course

    Science.gov (United States)

    Kotey, Bernice; Anderson, Phil

    2006-01-01

    Purpose: The purpose of the paper is to compare the performance of distance-learning students in a Small Business Management (SBM) course with that of internal (on-campus) students, and to examine students' demographics and information processing systems for their moderating effects on performance of each student group.…

  11. An Analysis of the Relationship between Distance from Campus and GPA of Commuter Students

    Science.gov (United States)

    Nelson, Danielle; Misra, Kaustav; Sype, Gail E.; Mackie, Wayne

    2016-01-01

    A variety of factors influence a student's ability to succeed in college and complete a degree program. Students who live on-campus, at least during their freshman year, have been shown to be more likely to complete their degrees than are students who live off-campus. Students who are commuters may have more demands on their time and may have…

  12. Scandal on campus. Dietrich Schwanitz reads Niklas Luhmann’s systems theory

    Directory of Open Access Journals (Sweden)

    Andrzej Denka

    2015-12-01

    Full Text Available Niklas Luhmann (1927–1998 is one of the most distinguished sociologists of the twentieth cen-tury and the author of systems theory, which to a great extent has been accommodated into lin-guistics. Dietrich Schwanitz (1940–2004, an anglicist, is one of the most interesting interpreters of Luhmann on the basis of literary studies. Schwanitz is also known as a writer and author of the novel Campus (Der Campus, 1995. The main character, a sociologist, Hanno Hackmann, is wrongly accused of the sexual harassment and rape of a student. His reckless romance is exploited by various people in the university milieu to achieve their own goals. In fact, these people are, however, only the representatives of various social systems, especially politics and the media. Striving for re-election, the university rector needs this matter for his campaign, and the media are only interested in a scandalous story to be exploited for some time. Social communication does not reflect reality, and, at the same time, can be described as based on the “reduction of complexi-ty” (“Komplexitätsreduktion”. This is one of the most important concepts in Niklas Luhmann’s work. It turns out that systems theory provides the specific key to interpret the novel.

  13. Who Decides What Is Acceptable Speech on Campus? Why Restricting Free Speech Is Not the Answer.

    Science.gov (United States)

    Ceci, Stephen J; Williams, Wendy M

    2018-05-01

    Recent protests on dozens of campuses have led to the cancellation of controversial talks, and violence has accompanied several of these protests. Psychological science provides an important lens through which to view, understand, and potentially reduce these conflicts. In this article, we frame opposing sides' arguments within a long-standing corpus of psychological research on selective perception, confirmation bias, myside bias, illusion of understanding, blind-spot bias, groupthink/in-group bias, motivated skepticism, and naive realism. These concepts inform dueling claims: (a) the protestors' violence was justified by a higher moral responsibility to prevent marginalized groups from being victimized by hate speech, versus (b) the students' right to hear speakers was infringed upon. Psychological science cannot, however, be the sole arbiter of these campus debates; legal and philosophical considerations are also relevant. Thus, we augment psychological science with insights from these literatures to shed light on complexities associated with positions supporting free speech and those protesting hate speech. We conclude with a set of principles, most supported by empirical research, to inform university policies and help ensure vigorous freedom of expression within the context of an inclusive, diverse community.

  14. A Small Modular Laboratory Hall Effect Thruster

    Science.gov (United States)

    Lee, Ty Davis

    Electric propulsion technologies promise to revolutionize access to space, opening the door for mission concepts unfeasible by traditional propulsion methods alone. The Hall effect thruster is a relatively high thrust, moderate specific impulse electric propulsion device that belongs to the class of electrostatic thrusters. Hall effect thrusters benefit from an extensive flight history, and offer significant performance and cost advantages when compared to other forms of electric propulsion. Ongoing research on these devices includes the investigation of mechanisms that tend to decrease overall thruster efficiency, as well as the development of new techniques to extend operational lifetimes. This thesis is primarily concerned with the design and construction of a Small Modular Laboratory Hall Effect Thruster (SMLHET), and its operation on argon propellant gas. Particular attention was addressed at low-cost, modular design principles, that would facilitate simple replacement and modification of key thruster parts such as the magnetic circuit and discharge channel. This capability is intended to facilitate future studies of device physics such as anomalous electron transport and magnetic shielding of the channel walls, that have an impact on thruster performance and life. Preliminary results demonstrate SMLHET running on argon in a manner characteristic of Hall effect thrusters, additionally a power balance method was utilized to estimate thruster performance. It is expected that future thruster studies utilizing heavier though more expensive gases like xenon or krypton, will observe increased efficiency and stability.

  15. June 1992 Hall B collaboation meeting

    International Nuclear Information System (INIS)

    Dennis, L.

    1992-01-01

    The Hall B collaboration meeting at the CEBAF 1992 Summer Workshop consisted of technical and physics working group meetings, a special beam line devices working group meeting the first meeting of the membership committee, a technical representatives meeting and a full collaboration meeting. Highlights of these meetings are presented in this report

  16. Chapin Hall Projects and Publications. Autumn 1999.

    Science.gov (United States)

    Chicago Univ., IL. Chapin Hall Center for Children.

    This guide chronicles the ongoing work and writings of the Chapin Hall Center for Children at the University of Chicago, a policy research center dedicated to bringing sound information, rigorous analyses, innovative ideas, and an independent, multidisciplinary perspective to bear on policies and programs affecting children. This guide, organized…

  17. Quantum Hall Conductivity and Topological Invariants

    Science.gov (United States)

    Reyes, Andres

    2001-04-01

    A short survey of the theory of the Quantum Hall effect is given emphasizing topological aspects of the quantization of the conductivity and showing how topological invariants can be derived from the hamiltonian. We express these invariants in terms of Chern numbers and show in precise mathematical terms how this relates to the Kubo formula.

  18. Room acoustic properties of concert halls

    DEFF Research Database (Denmark)

    Gade, Anders Christian

    1996-01-01

    A large database of values of various room acoustic parameters has provided the basis for statistical analyses of how and how much the acoustic properties of concert halls are influenced by their size, shape, and absorption area (as deduced from measured reverberation time). The data have been...

  19. Pseudospin anisotropy classification of quantum Hall ferromagnets

    Czech Academy of Sciences Publication Activity Database

    Jungwirth, Tomáš; MacDonald, A. H.

    2000-01-01

    Roč. 63, č. 3 (2000), s. 035305-1 - 035305-9 ISSN 0163-1829 R&D Projects: GA ČR GA202/98/0085 Institutional research plan: CEZ:AV0Z1010914 Keywords : quantum Hall ferromagnets * anisotropy Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.065, year: 2000

  20. Anomalous Hall effect in disordered multiband metals

    Czech Academy of Sciences Publication Activity Database

    Kovalev, A.A.; Sinova, Jairo; Tserkovnyak, Y.

    2010-01-01

    Roč. 105, č. 3 (2010), 036601/1-036601/4 ISSN 0031-9007 Institutional research plan: CEZ:AV0Z10100521 Keywords : anomalous Hall effect * spintronics Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 7.621, year: 2010

  1. Anomalous Hall conductivity: Local orbitals approach

    Czech Academy of Sciences Publication Activity Database

    Středa, Pavel

    2010-01-01

    Roč. 82, č. 4 (2010), 045115/1-045115/9 ISSN 1098-0121 Institutional research plan: CEZ:AV0Z10100521 Keywords : anomalous Hall effect * Berry phase correction * orbital polarization momentum Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.772, year: 2010

  2. Quantization and hall effect: necessities and difficulties

    International Nuclear Information System (INIS)

    Ahmed Bouketir; Hishamuddin Zainuddin

    1999-01-01

    The quantization procedure is a necessary tool for a proper understanding of many interesting quantum phenomena in modern physics. In this note, we focus on geometrical framework for such procedures, particularly the group-theoretic approach and their difficulties. Finally we look through the example of Hall effect as a quantized macroscopic phenomenon with group-theoretic quantization approach. (author)

  3. Spin Hall effect on a noncommutative space

    International Nuclear Information System (INIS)

    Ma Kai; Dulat, Sayipjamal

    2011-01-01

    We study the spin-orbital interaction and the spin Hall effect of an electron moving on a noncommutative space under the influence of a vector potential A(vector sign). On a noncommutative space, we find that the commutator between the vector potential A(vector sign) and the electric potential V 1 (r(vector sign)) of the lattice induces a new term, which can be treated as an effective electric field, and the spin Hall conductivity obtains some correction. On a noncommutative space, the spin current and spin Hall conductivity have distinct values in different directions, and depend explicitly on the noncommutative parameter. Once this spin Hall conductivity in different directions can be measured experimentally with a high level of accuracy, the data can then be used to impose bounds on the value of the space noncommutativity parameter. We have also defined a new parameter, σ=ρθ (ρ is the electron concentration, θ is the noncommutativity parameter), which can be measured experimentally. Our approach is based on the Foldy-Wouthuysen transformation, which gives a general Hamiltonian of a nonrelativistic electron moving on a noncommutative space.

  4. Prospect of quantum anomalous Hall and quantum spin Hall effect in doped kagome lattice Mott insulators.

    Science.gov (United States)

    Guterding, Daniel; Jeschke, Harald O; Valentí, Roser

    2016-05-17

    Electronic states with non-trivial topology host a number of novel phenomena with potential for revolutionizing information technology. The quantum anomalous Hall effect provides spin-polarized dissipation-free transport of electrons, while the quantum spin Hall effect in combination with superconductivity has been proposed as the basis for realizing decoherence-free quantum computing. We introduce a new strategy for realizing these effects, namely by hole and electron doping kagome lattice Mott insulators through, for instance, chemical substitution. As an example, we apply this new approach to the natural mineral herbertsmithite. We prove the feasibility of the proposed modifications by performing ab-initio density functional theory calculations and demonstrate the occurrence of the predicted effects using realistic models. Our results herald a new family of quantum anomalous Hall and quantum spin Hall insulators at affordable energy/temperature scales based on kagome lattices of transition metal ions.

  5. Digital technology impacts on the Arnhem transfer hall structural design

    NARCIS (Netherlands)

    Van de Straat, R.; Hofman, S.; Coenders, J.L.; Paul, J.C.

    2015-01-01

    The new Transfer Hall in Arnhem is one of the key projects to prepare the Dutch railways for the increased future demands for capacity. UNStudio developed a master plan in 1996 for the station area of which the completion of the Transfer Hall in 2015 will be a final milestone. The Transfer Hall is a

  6. Magnetoresistance in quantum Hall metals due to Pancharatnam ...

    Indian Academy of Sciences (India)

    Abstract. We derive the trial Hall resistance formula for the quantum Hall metals to address both the integer and fractional quantum Hall effects. Within the degenerate (and crossed) Landau levels, and in the presence of changing magnetic field strength, one can invoke two physical processes responsible for the electron ...

  7. Destruction of the fractional quantum Hall effect by disorder

    International Nuclear Information System (INIS)

    Laughlin, R.B.

    1985-07-01

    It is suggested that Hall steps in the fractional quantum Hall effect are physically similar to those in the ordinary quantum Hall effect. This proposition leads to a simple scaling diagram containing a new type of fixed point, which is identified with the destruction of the fractional states by disorder. 15 refs., 3 figs

  8. A Hall probe technique for characterizing high-temperature superconductors

    International Nuclear Information System (INIS)

    Zhang, J.; Sheldon, P.; Ahrenkiel, R.K.

    1992-01-01

    Thin-film GaAs Hall probes were fabricated by molecular beam epitaxy technology. A contactless technique was developed to characterize thin-film, high-temperature superconducting (HTSC) materials. The Hall probes detected the ac magnetic flux penetration through the high-temperature superconducting materials. The Hall detector has advantages over the mutual inductance magnetic flux detector

  9. Spin-singlet hierarchy in the fractional quantum Hall effect

    OpenAIRE

    Ino, Kazusumi

    1999-01-01

    We show that the so-called permanent quantum Hall states are formed by the integer quantum Hall effects on the Haldane-Rezayi quantum Hall state. Novel conformal field theory description along with this picture is deduced. The odd denominator plateaux observed around $\

  10. Topological honeycomb magnon Hall effect: A calculation of thermal Hall conductivity of magnetic spin excitations

    Energy Technology Data Exchange (ETDEWEB)

    Owerre, S. A., E-mail: solomon@aims.ac.za [African Institute for Mathematical Sciences, 6 Melrose Road, Muizenberg, Cape Town 7945, South Africa and Perimeter Institute for Theoretical Physics, 31 Caroline St. N., Waterloo, Ontario N2L 2Y5 (Canada)

    2016-07-28

    Quite recently, the magnon Hall effect of spin excitations has been observed experimentally on the kagome and pyrochlore lattices. The thermal Hall conductivity κ{sup xy} changes sign as a function of magnetic field or temperature on the kagome lattice, and κ{sup xy} changes sign upon reversing the sign of the magnetic field on the pyrochlore lattice. Motivated by these recent exciting experimental observations, we theoretically propose a simple realization of the magnon Hall effect in a two-band model on the honeycomb lattice. The magnon Hall effect of spin excitations arises in the usual way via the breaking of inversion symmetry of the lattice, however, by a next-nearest-neighbour Dzyaloshinsky-Moriya interaction. We find that κ{sup xy} has a fixed sign for all parameter regimes considered. These results are in contrast to the Lieb, kagome, and pyrochlore lattices. We further show that the low-temperature dependence on the magnon Hall conductivity follows a T{sup 2} law, as opposed to the kagome and pyrochlore lattices. These results suggest an experimental procedure to measure thermal Hall conductivity within a class of 2D honeycomb quantum magnets and ultracold atoms trapped in a honeycomb optical lattice.

  11. Diagnostics Systems for Permanent Hall Thrusters Development

    Science.gov (United States)

    Ferreira, Jose Leonardo; Soares Ferreira, Ivan; Santos, Jean; Miranda, Rodrigo; Possa, M. Gabriela

    This work describes the development of Permanent Magnet Hall Effect Plasma Thruster (PHALL) and its diagnostic systems at The Plasma Physics Laboratory of University of Brasilia. The project consists on the construction and characterization of plasma propulsion engines based on the Hall Effect. Electric thrusters have been employed in over 220 successful space missions. Two types stand out: the Hall-Effect Thruster (HET) and the Gridded Ion Engine (GIE). The first, which we deal with in this project, has the advantage of greater simplicity of operation, a smaller weight for the propulsion subsystem and a longer shelf life. It can operate in two configurations: magnetic layer and anode layer, the difference between the two lying in the positioning of the anode inside the plasma channel. A Hall-Effect Thruster-HET is a type of plasma thruster in which the propellant gas is ionized and accelerated by a magneto hydrodynamic effect combined with electrostatic ion acceleration. So the essential operating principle of the HET is that it uses a J x B force and an electrostatic potential to accelerate ions up to high speeds. In a HET, the attractive negative charge is provided by electrons at the open end of the Thruster instead of a grid, as in the case of the electrostatic ion thrusters. A strong radial magnetic field is used to hold the electrons in place, with the combination of the magnetic field and the electrostatic potential force generating a fast circulating electron current, the Hall current, around the axis of the Thruster, mainly composed by drifting electrons in an ion plasma background. Only a slow axial drift towards the anode occurs. The main attractive features of the Hall-Effect Thruster are its simple design and operating principles. Most of the Hall-Effect Thrusters use electromagnet coils to produce the main magnetic field responsible for plasma generation and acceleration. In this paper we present a different new concept, a Permanent Magnet Hall

  12. Valley-chiral quantum Hall state in graphene superlattice structure

    Science.gov (United States)

    Tian, H. Y.; Tao, W. W.; Wang, J.; Cui, Y. H.; Xu, N.; Huang, B. B.; Luo, G. X.; Hao, Y. H.

    2016-05-01

    We theoretically investigate the quantum Hall effect in a graphene superlattice (GS) system, in which the two valleys of graphene are coupled together. In the presence of a perpendicular magnetic field, an ordinary quantum Hall effect is found with the sequence σxy=ν e^2/h(ν=0,+/-1,+/-2,\\cdots) . At the zeroth Hall platform, a valley-chiral Hall state stemming from the single K or K' valley is found and it is localized only on one sample boundary contributing to the longitudinal conductance but not to the Hall conductivity. Our findings may shed light on the graphene-based valleytronics applications.

  13. Accurate micro Hall effect measurements on scribe line pads

    DEFF Research Database (Denmark)

    Østerberg, Frederik Westergaard; Petersen, Dirch Hjorth; Wang, Fei

    2009-01-01

    Hall mobility and sheet carrier density are important parameters to monitor in advanced semiconductor production. If micro Hall effect measurements are done on small pads in scribe lines, these parameters may be measured without using valuable test wafers. We report how Hall mobility can...... be extracted from micro four-point measurements performed on a rectangular pad. The dimension of the investigated pad is 400 × 430 ¿m2, and the probe pitches range from 20 ¿m to 50 ¿m. The Monte Carlo method is used to find the optimal way to perform the Hall measurement and extract Hall mobility most...

  14. Giant photonic Hall effect in magnetophotonic crystals.

    Science.gov (United States)

    Merzlikin, A M; Vinogradov, A P; Inoue, M; Granovsky, A B

    2005-10-01

    We have considered a simple, square, two-dimensional (2D) PC built of a magneto-optic matrix with square holes. It is shown that using such a magnetophotonic crystal it is possible to deflect a light beam at very large angles by applying a nonzero external magnetic field. The effect is called the giant photonic Hall effect (GPHE) or the magnetic superprism effect. The GPHE is based on magneto-optical properties, as is the photonic Hall effect [B. A. van Tiggelen and G. L. J. A. Rikken, in, edited by V. M. Shalaev (Springer-Verlag, Berlin, 2002), p. 275]; however GPHE is not caused by asymmetrical light scattering but rather by the influence of an external magnetic field on the photonic band structure.

  15. Assessment of elevator rope using Hall Sensor

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong O; Yoon, Woon Ha; Son, Young Ho; Kim, Jung Woo [Korea Institute of Machinery and Materials, Daejeon (Korea, Republic of); Lee, Jong Ku [Pukyung National University, Pusan (Korea, Republic of)

    2003-07-01

    Defect detection of wire rope for an elevator was investigated through the measurement of magnetic flux leakage. The types of defect usually found in wire rope categorized such as inner and outer wire breakage and wear. The specimens that has artificial defects were magnetized via permanent magnet, and measurement of magnetic flux leakage on the defects was performed with Hall sensor. In wire broken model, a defect smaller than 0.4 mm and 1 mm in depth on outer and inner wire rope, respectively, could be detected well. In wear model, smaller defect could not be detected clearly, however, appearance of changing of total magnetic flux during magnetic pole of the sensor passing through a defect 0.2 mm in depth at 4 mm or above width could make possible to detect it. From the results, the measurement via Hall sensor might be useful tool for defect detection of wire rope.

  16. Assesment of elevator rope using hall sensor

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong O; Yoon, Woon Ha; Son, Young Ho [Korea Institute of Machinery and Materials, Daejeon (Korea, Republic of); Kim, Jung Woo; Lee, Jong Ku [Pukyong National University, Pusan (Korea, Republic of)

    2003-05-15

    Defect detection of wire rope for an elevator was investigated through the measurement of magnetic flux leakage. The types of defect usually found in wire rope categorized such as inner and outer wire breakage and wear. The specimens that has artificial defects were magnetized via permanent magnet, and measurement of magnetic flux leakage on the defects was performed with Hall sensor. In wire broken model, a defect smaller than 0.4mm and 1mm in depth on outer and inner wire rope, respectively, could be detected well. In wear model, smaller defect could not be detected clearly, however, appearance of changing of total magnetic flux during magnetic pole of the sensor passing through a defect 0.2mm in depth at 4mm or above width could make possible to detect it. From the results, the measurement via Hall sensor might be useful tool for defect detection of wire rope.

  17. Infinite symmetry in the quantum Hall effect

    Directory of Open Access Journals (Sweden)

    Lütken C.A.

    2014-04-01

    Full Text Available The new states of matter and concomitant quantum critical phenomena revealed by the quantum Hall effect appear to be accompanied by an emergent modular symmetry. The extreme rigidity of this infinite symmetry makes it easy to falsify, but two decades of experiments have failed to do so, and the location of quantum critical points predicted by the symmetry is in increasingly accurate agreement with scaling experiments. The symmetry severely constrains the structure of the effective quantum field theory that encodes the low energy limit of quantum electrodynamics of 1010 charges in two dirty dimensions. If this is a non-linear σ-model the target space is a torus, rather than the more familiar sphere. One of the simplest toroidal models gives a critical (correlation length exponent that agrees with the value obtained from numerical simulations of the quantum Hall effect.

  18. Stuart Hall and Cultural Studies, circa 1983

    Directory of Open Access Journals (Sweden)

    Ann Curthoys

    2017-11-01

    Full Text Available Stuart Hall sought to internationalise theoretical debates and to create Cultural Studies as interdisciplinary. We chart his theoretical journey through a detailed examination of a series of lectures delivered in 1983 and now published for the first time. In these lectures, he discusses theorists such as E.P. Thompson, Raymond Williams, Louis Althusser, Levi Strauss and Antonio Gramsci, and explores the relationship between ideas and social structure, the specificities of class and race, and the legacies of slavery. We note his turn towards metaphors of divergence and dispersal and highlight how autobiographical and deeply personal Hall is in these lectures, especially in his ego histoire moment of traumatic memory recovery.

  19. Hall magnetohydrodynamics: Conservation laws and Lyapunov stability

    International Nuclear Information System (INIS)

    Holm, D.D.

    1987-01-01

    Hall electric fields produce circulating mass flow in confined ideal-fluid plasmas. The conservation laws, Hamiltonian structure, equilibrium state relations, and Lyapunov stability conditions are presented here for ideal Hall magnetohydrodynamics (HMHD) in two and three dimensions. The approach here is to use the remarkable array of nonlinear conservation laws for HMHD that follow from its Hamiltonian structure in order to construct explicit Lyapunov functionals for the HMHD equilibrium states. In this way, the Lyapunov stability analysis provides classes of HMHD equilibria that are stable and whose linearized initial-value problems are well posed (in the sense of possessing continuous dependence on initial conditions). Several examples are discussed in both two and three dimensions

  20. Music hall Markneukirchen; Musikhalle in Markneukirchen

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1996-01-01

    The article presents the new building of the music hall Markneukirchen. From the planned use of the building result very high demands on the ventilation system in order to keep to a sound power level of less than 30 dB(A) in the hall. The building services are dealt with using numerous flowsheets and diagrams: Heat supply, ventilation system, sanitary system, building management, instrumentation and control, electric and lighting systems. (BWI) [Deutsch] Der vorliegende Beitrag stellt den Neubau der Musikhalle Markneukirchen vor. Durch das Nutzungskonzept ergeben sich fuer die Einhaltung eines Schalleistungspegels von weniger als 30 dB(A) im Saalbereich an die Lueftungsanlage sehr hohe Ansprueche. Es werden die raumlufttechnischen Anlagen anhand zahlreicher Flussbilder und Abbildungen vorgestellt: Waermeversorgung, Lueftungstechnik, Sanitaertechnik, Gebaeudeleit- und MSR-Technik, Elektro- und Lichttechnik. (BWI)

  1. Theory of fractional quantum hall effect

    International Nuclear Information System (INIS)

    Kostadinov, I.Z.

    1985-08-01

    A theory of the Fractional Quantum Hall Effect is constructed based on magnetic flux fractionization, which lead to instability of the system against selfcompression. A theorem is proved stating that arbitrary potentials fail to lift a specific degeneracy of the Landau level. For the case of 1/3 fractional filling a model 3-particles interaction is constructed breaking the symmetry. The rigid 3-particles wave function plays the role of order parameter. In a BCS type of theory the gap in the single particles spectrum is produced by the 3-particles interaction. The mean field critical behaviour and critical parameters are determined as well as the Ginsburg-Landau equation coefficients. The Hall conductivity is calculated from the first principles and its temperature dependence is found. The simultaneous tunnelling of 3,5,7 etc. electrons and quantum interference effects are predicted. (author)

  2. Coulomb blockade in hierarchical quantum Hall droplets

    International Nuclear Information System (INIS)

    Cappelli, Andrea; Georgiev, Lachezar S; Zemba, Guillermo R

    2009-01-01

    The degeneracy of energy levels in a quantum dot of Hall fluid, leading to conductance peaks, can be readily derived from the partition functions of conformal field theory. Their complete expressions can be found for Hall states with both Abelian and non-Abelian statistics, upon adapting known results for the annulus geometry. We analyze the Abelian states with hierarchical filling fractions, ν = m/(mp ± 1), and find a non-trivial pattern of conductance peaks. In particular, each one of them occurs with a characteristic multiplicity, which is due to the extended symmetry of the m-folded edge. Experimental tests of the multiplicity can shed more light on the dynamics of this composite edge. (fast track communication)

  3. Assessment of elevator rope using Hall Sensor

    International Nuclear Information System (INIS)

    Lee, Jong O; Yoon, Woon Ha; Son, Young Ho; Kim, Jung Woo; Lee, Jong Ku

    2003-01-01

    Defect detection of wire rope for an elevator was investigated through the measurement of magnetic flux leakage. The types of defect usually found in wire rope categorized such as inner and outer wire breakage and wear. The specimens that has artificial defects were magnetized via permanent magnet, and measurement of magnetic flux leakage on the defects was performed with Hall sensor. In wire broken model, a defect smaller than 0.4 mm and 1 mm in depth on outer and inner wire rope, respectively, could be detected well. In wear model, smaller defect could not be detected clearly, however, appearance of changing of total magnetic flux during magnetic pole of the sensor passing through a defect 0.2 mm in depth at 4 mm or above width could make possible to detect it. From the results, the measurement via Hall sensor might be useful tool for defect detection of wire rope.

  4. Assesment of elevator rope using hall sensor

    International Nuclear Information System (INIS)

    Lee, Jong O; Yoon, Woon Ha; Son, Young Ho; Kim, Jung Woo; Lee, Jong Ku

    2003-01-01

    Defect detection of wire rope for an elevator was investigated through the measurement of magnetic flux leakage. The types of defect usually found in wire rope categorized such as inner and outer wire breakage and wear. The specimens that has artificial defects were magnetized via permanent magnet, and measurement of magnetic flux leakage on the defects was performed with Hall sensor. In wire broken model, a defect smaller than 0.4mm and 1mm in depth on outer and inner wire rope, respectively, could be detected well. In wear model, smaller defect could not be detected clearly, however, appearance of changing of total magnetic flux during magnetic pole of the sensor passing through a defect 0.2mm in depth at 4mm or above width could make possible to detect it. From the results, the measurement via Hall sensor might be useful tool for defect detection of wire rope.

  5. Judy Estes Hall (1940-2015).

    Science.gov (United States)

    Sammons, Morgan T; Boucher, Andrew

    2016-01-01

    Presents an obituary for Judy Estes Hall, who passed away on November 24, 2015. Hall served as the Executive Officer of the National Register of Health Service Psychologists until her retirement in 2013. She is a recognized expert in the development of education and training standards for the profession of psychology, she also made significant contributions in the field of international psychology, where she was a renowned expert in cross-national credentialing and an advocate for commonality in licensing standards. She was the coauthor of one edited volume and author of more than 60 journal articles, book chapters, and professional publications. A passionate advocate for the advancement of women in psychology, a devoted mother and grandmother, a connoisseur of wine and international traveler extraordinaire, she touched the personal and professional lives of many. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  6. An Analysis of White Student Engagement at Public HBCUs

    Science.gov (United States)

    Carter, Joelle Davis; Fountaine, Tiffany Patrice

    2012-01-01

    The steady increase of White undergraduates attending public Historically Black Colleges and Universities (HBCUs) compels educators to better understand White students' collegiate experiences at HBCUs. One lens to assess these experiences is through examining their engagement on campus. Student engagement is defined as the amount of time and…

  7. Perceptions of the Campus Climate for Nonreligious Students

    Science.gov (United States)

    Rockenbach, Alyssa N.; Mayhew, Matthew J.; Bowman, Nicholas A.

    2015-01-01

    Based on a campus climate survey involving 633 respondents from two institutions, this study examined perceptions of nonreligious acceptance on campus as a function of students' religious identification and strength of commitment to worldview. The findings suggest that atheist students are less inclined than are their peers to perceive a positive…

  8. Self-Reported Reasons for Why College Students Drink.

    Science.gov (United States)

    Klein, Hugh

    1992-01-01

    Surveyed 526 on-campus college students about their reasons for drinking alcoholic beverages. Results indicated that students reported drinking because they liked the taste of alcohol and because drinking helped them celebrate special occasions. Negative or disintegrative reasons were endorsed rarely, and then usually by males, Greek organization…

  9. Testing a Beverage and Fruit/Vegetable Education Intervention in a University Dining Hall.

    Science.gov (United States)

    Scourboutakos, Mary J; Mah, Catherine L; Murphy, Sarah A; Mazza, Frank N; Barrett, Nathanael; McFadden, Bill; L'Abbé, Mary R

    2017-06-01

    To test the effect of a nutrition intervention that included education and 2 labeling components on students' food choices. Repeat cross-sectional study taking place on 6 dinner occasions before and 6 afterward. The study was conducted during dinner meals in a buffet-style dining hall in a university campus residence, where students paid a set price and consumed all they cared to eat. University students (n = 368 to 510) visited the cafeteria on each of the data collection dates. Fruit and vegetable consumption were encouraged; sugar-sweetened beverage consumption was discouraged using physical activity calorie equivalent labeling. Beverage choices and vegetable/fruit bar visits. Logistic regression was used to compare the proportion of student who selected each beverage, fruit, or vegetable before and after the intervention, while controlling for menu and gender as covariates. There was a significant decrease in the proportion of students selecting a sugar-sweetened beverage before vs after the intervention (49% vs 41%, respectively; P = .004) and an increase in students choosing water (43% vs 54%, respectively; P < .001). There was a significant increase in students who took fruit after the intervention (36%; P < .001) vs before (30%). The number of students visiting the vegetable bar significantly increased from 60% to 72% (P < .001). This intervention may be a way to encourage healthy dietary choices in campus dining halls. Copyright © 2017. Published by Elsevier Inc.

  10. The Journeys of Dr. G: a blog designed for students to learn about the life of a faculty member in the Earth sciences

    Science.gov (United States)

    Guertin, L. A.

    2013-12-01

    I teach at a small campus in the Penn State system that offers the first two years of science programming. There are no upper-division science courses taught, and science faculty are not provided dedicated space for research activities. Although all of the tenure-line faculty are required to do research, the research culture on campus is not visible nor shared with students. Students view the science faculty only as classroom instructors and are not aware of our other responsibilities and how we engage in our disciplines outside of teaching. For example, when I leave during the semester to attend a conference, students joke with me that I must be going on vacation, as the primarily freshmen/sophomore students in my introductory-level general education Earth science courses do not understand why I would not show up to teach. Over the years, I have become more frustrated with students not understanding that I am more than a classroom instructor, that my professional identity includes scientist, researcher, mentor, conference presenter and innovator. But this is not the fault of the students. I cannot magically create a geology research laboratory on campus, but I can do a better job sharing with students the responsibilities that go along with a faculty position, including the research 'hat' that I wear. To address this lack of knowledge, upon my return from a conference, I would give a full-day PowerPoint presentation to my classes with photos about what I did and learned while I was away. I would take photos of the room where I gave a talk, the displays in the exhibit and poster halls, etc. Although I was pleased with the reception of these classroom lectures by the students, I soon realized that these presentations were a 'one and done' format; once I lectured, the students never had access to the information again. In addition, I am noticing recent rules and policies against taking photographs in exhibit and poster halls as well as other areas of conference

  11. Homotopy arguments for quantized Hall conductivity

    CERN Document Server

    Richter, T

    2002-01-01

    Using the strong localization bounds obtained by the Aizenman-Molcanov method for a particle in a magnetic field and a disordered potential, we show that the zero-temperature Hall conductivity of a gas of such particles is quantized and constant as long as both Fermi energy and disorder coupling parameter vary in a region of strong localization of the corresponding two-dimensional phase diagram.

  12. SPS beam to the West Hall

    CERN Multimedia

    CERN PhotoLab

    1976-01-01

    One of the two target stations feeding the West Hall (see Annual Report 1976). After the proton beam was split into three branches, the outer two were directed on to targets in the cast iron shielding box, the centre one passing through the box to another target station downstream. Five different targets could be put in each beam, controlled by the mechanism seen on top.

  13. Anomalous hall effect in ferromagnetic semiconductors

    Czech Academy of Sciences Publication Activity Database

    Jungwirth, Tomáš; Niu, Q.; MacDonald, A. H.

    2002-01-01

    Roč. 88, č. 20 (2002), s. 207208-1-207208-4 ISSN 0031-9007 R&D Projects: GA ČR GA202/02/0912; GA MŠk OC P5.10 Institutional research plan: CEZ:AV0Z1010914 Keywords : ferromagnetic semiconductors * anomalous Hall effect Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 7.323, year: 2002

  14. A hall for assembly and cryogenic tests

    International Nuclear Information System (INIS)

    Beaunier, J.; Buhler, S.; Caruette, A.; Chevrollier, R.; Junquera, T.; Le Scornet, J.C.

    1999-01-01

    Cryodrome, an assembly hall and the testing ground for cryogenic equipment and R and D experiments for the superconducting cavities is going to be transformed for its future missions. The cryogenic utilities, especially the He low pressure pumping capacity, was rearranged and extended to a new area. Space was provided to install CRYHOLAB, a new horizontal cryostat for cavity testing. Automatic control and supervision of the utilities and the experimental area are rebuilt and updated. (authors)

  15. Comparing the Internet Usage of Pre-service Language Teachers With Teachers of Other Subjects: Distance Learning vs. On-Campus Learning

    Directory of Open Access Journals (Sweden)

    Mehmet Firat

    2017-01-01

    Full Text Available Teachers play a crucial role in helping individuals gain adequate Internet competency, which requires teachers themselves to be Internet-literate. The purpose of this study is to investigate the Internet use of the distance and on-campus pre-service teachers of language and other disciplines by multiple parameters. A total of 789 teacher candidates participated in this survey. The findings show that the candidate teachers in on-campus and distance-learning programs have an average level of Internet usage adequacy and that the younger candidate teachers and those in higher classes use the Internet more frequently. Pre-service foreign language teachers have been found to have a moderate level of Internet usage frequency, adequacy and technology ownership in comparison with the other preservice teacher groups.

  16. Generic superweak chaos induced by Hall effect

    Science.gov (United States)

    Ben-Harush, Moti; Dana, Itzhack

    2016-05-01

    We introduce and study the "kicked Hall system" (KHS), i.e., charged particles periodically kicked in the presence of uniform magnetic (B ) and electric (E ) fields that are perpendicular to each other and to the kicking direction. We show that for resonant values of B and E and in the weak-chaos regime of sufficiently small nonintegrability parameter κ (the kicking strength), there exists a generic family of periodic kicking potentials for which the Hall effect from B and E significantly suppresses the weak chaos, replacing it by "superweak" chaos (SWC). This means that the system behaves as if the kicking strength were κ2 rather than κ . For E =0 , SWC is known to be a classical fingerprint of quantum antiresonance, but it occurs under much less generic conditions, in particular only for very special kicking potentials. Manifestations of SWC are a decrease in the instability of periodic orbits and a narrowing of the chaotic layers, relative to the ordinary weak-chaos case. Also, for global SWC, taking place on an infinite "stochastic web" in phase space, the chaotic diffusion on the web is much slower than the weak-chaos one. Thus, the Hall effect can be relatively stabilizing for small κ . In some special cases, the effect is shown to cause ballistic motion for almost all parameter values. The generic global SWC on stochastic webs in the KHS appears to be the two-dimensional closest analog to the Arnol'd web in higher dimensional systems.

  17. Anode Fall Formation in a Hall Thruster

    International Nuclear Information System (INIS)

    Dorf, Leonid A.; Raitses, Yevgeny F.; Smirnov, Artem N.; Fisch, Nathaniel J.

    2004-01-01

    As was reported in our previous work, accurate, nondisturbing near-anode measurements of the plasma density, electron temperature, and plasma potential performed with biased and emissive probes allowed the first experimental identification of both electron-repelling (negative anode fall) and electron-attracting (positive anode fall) anode sheaths in Hall thrusters. An interesting new phenomenon revealed by the probe measurements is that the anode fall changes from positive to negative upon removal of the dielectric coating, which appears on the anode surface during the course of Hall thruster operation. As reported in the present work, energy dispersion spectroscopy analysis of the chemical composition of the anode dielectric coating indicates that the coating layer consists essentially of an oxide of the anode material (stainless steel). However, it is still unclear how oxygen gets into the thruster channel. Most importantly, possible mechanisms of anode fall formation in a Hall thruster with a clean and a coated anodes are analyzed in this work; practical implication of understanding the general structure of the electron-attracting anode sheath in the case of a coated anode is also discussed

  18. Josephson tunneling in bilayer quantum Hall system

    International Nuclear Information System (INIS)

    Ezawa, Z.F.; Tsitsishvili, G.; Sawada, A.

    2012-01-01

    A Bose–Einstein condensation is formed by composite bosons in the quantum Hall state. A composite boson carries the fundamental charge (−e). We investigate Josephson tunneling of such charges in the bilayer quantum Hall system at the total filling ν=1. We show the existence of the critical current for the tunneling current to be coherent and dissipationless. Our results explain recent experiments due to [L. Tiemann, Y. Yoon, W. Dietsche, K. von Klitzing, W. Wegscheider, Phys. Rev. B 80 (2009) 165120] and due to [Y. Yoon, L. Tiemann, S. Schmult, W. Dietsche, K. von Klitzing, Phys. Rev. Lett. 104 (2010) 116802]. We predict also how the critical current changes as the sample is tilted in the magnetic field. -- Highlights: ► Composite bosons undergo Bose–Einstein condensation to form the bilayer quantum Hall state. ► A composite boson is a single electron bound to a flux quantum and carries one unit charge. ► Quantum coherence develops due to the condensation. ► Quantum coherence drives the supercurrent in each layer and the tunneling current. ► There exists the critical input current so that the tunneling current is coherent and dissipationless.

  19. Familial Pallister-Hall in adulthood.

    Science.gov (United States)

    Talsania, Mitali; Sharma, Rohan; Sughrue, Michael E; Scofield, R Hal; Lim, Jonea

    2017-10-01

    Pallister Hall syndrome is autosomal dominant disorder usually diagnosed in infants and children. Current diagnostic criteria include presence of hypothalamic hamartoma, post axial polydactyly and positive family history, but the disease has variable manifestations. Herein we report Pallister Hall syndrome diagnosed in a family where both patients were adults. A 59 year old man developed seizures 4 years prior to our evaluation of him, at which time imaging showed a hypothalamic hamartoma. The seizures were controlled medically. He did well until he had visual changes after a traumatic head injury. Repeat MRI showed slight expansion of the mass with formal visual field testing demonstrating bitemporal hemianopsia. There was no evidence of pituitary dysfunction except for large urine volume. He underwent surgery to debulk the hamartoma and the visual field defects improved. There was no hypopituitarism post-operatively, and the polydyspia resolved. His 29 year old daughter also had seizures and hypothalamic hamartoma. Both patients had had polydactyly with prior surgical correction in childhood. The daughter underwent genetic testing, which revealed a previously undescribed heterozygous single base pair deletion in exon 13 of the GLI3 gene causing a frameshift mutation. Further investigation into family history revealed multiple members in previous generations with polydactyly and/or seizures. Pallister-Hall syndrome is caused by an inherited autosomal dominant or de novo mutation in GLI3 gene. This rare syndrome has not had prevalence defined, however. Generally, diagnoses are made in the pediatric population. Our report adds to the few cases detected in adulthood.

  20. Keeping Kids on Campus.

    Science.gov (United States)

    Koenig, Mary Ellen

    1992-01-01

    Open-campus policies can devastate school lunch programs. Some school systems compete with fast-food outlets by offering similar menus; others hire private contractors to construct mall-like food courts. Several Colorado and California school districts have devised innovative programs to halt lunchtime flight without sacrificing nutrition. A…

  1. Mobile Phones on Campus

    Institute of Scientific and Technical Information of China (English)

    朴春宝

    2007-01-01

    After entering the 21st century, more and more people have mobile phones in China. At the end of 2002, there were 20 million mobile phone users. By the year 2005 the number has reached up to 30 million.

  2. Ties that Bind: A Social Network Approach To Understanding Student Integration and Persistence.

    Science.gov (United States)

    Thomas, Scott L.

    2000-01-01

    This study used a social network paradigm to examine college student integration of 329 college freshmen at a private liberal arts college. Analysis of the structural aspects of students' on-campus associations found differential effects of various social network characteristics on student commitment and persistence. (DB)

  3. Gender-Inclusive Housing Preferences: A Survey of College-Aged Transgender Students

    Science.gov (United States)

    Krum, Tiana E.; Davis, Kyle S.; Galupo, M. Paz

    2013-01-01

    Traditional on-campus housing assignments at colleges and universities are made on the basis of legal sex, where students are housed only with other students of the same legal sex. This method is problematic for transgender and gender-nonconforming students, who may not identify with the gender assigned to them at birth. Recently, some…

  4. The Perception of Safety between Drinkers and Non-Drinkers among U.S. College Students

    Science.gov (United States)

    Walter, Gayle; Florkowski, David; Anderson, Peter; Dunn, Micheal

    2014-01-01

    Increasing episodes of campus violence have warranted an investigation into college students' perception of safety on campus. In this study, 56,811 students responded to the Core Alcohol and Drug Survey during the 2010 academic school year. Numerous universities administered the survey and students completed the survey either in class or…

  5. Little Known, Much Needed: Addressing the Cocurricular Needs of LGBTQ Students

    Science.gov (United States)

    Ivory, Brian T.

    2012-01-01

    Due to the invisible nature of the lesbian, gay, bisexual, transgender, and queer (LGBTQ) undergraduate population, it is difficult for student affairs professionals at community colleges to identify and address the needs of sexual minority students on campus. Given the lack of literature regarding LGBTQ students at community colleges, student…

  6. Students' Perceptions of Online Courses: The Effect of Online Course Experience

    Science.gov (United States)

    Dobbs, Rhonda R.; Waid-Lindberg, Courtney A.; del Carmen, Alejandro

    2017-01-01

    While online learning is nothing new, research regarding student perceptions of online courses is limited and has generally focused on those who have taken online courses. Data were collected from 180 students taking criminal justice courses on campus at a large 4-year university in the Southwest and 100 students taking criminal justice courses in…

  7. A Project to Help Child Development Students Recognize Piagetian Developmental Stages.

    Science.gov (United States)

    Husmann, Ann

    This practicum report was designed to help child development students differentiate between the preoperational and concrete operational stages of the Piagetian cognitive hierarchy. The 36 on-campus and 63 instructional television students used a Piagetian Game booklet, which is included in the appendix. Using this booklet, students were able to…

  8. The STEM Lecture Hall: A Study of Effective Instructional Practices for Diverse Learners

    Science.gov (United States)

    Reimer, Lynn Christine

    First-generation, low-income, underrepresented minority (URM) and female undergraduates are matriculating into science, technology, engineering, and math (STEM) majors at unprecedented levels. However, a disproportionate number of these students end up graduating in non-STEM disciplines. Attrition rates have been observed to spike in conjunction with introductory STEM courses in chemistry, biology, and physics. These "gateway" courses tend to be housed in large, impersonal lecture halls. First-generation and URM students struggle in this environment, possibly because of instructors' reliance on lecture-based content delivery and rote memorization. Recent social psychological studies suggest the problem may be related to cultural mismatch, or misalignment between independent learning norms typical of American universities and interdependent learning expectancies for first-generation and URM students. Value-affirming and utility-value interventions yield impressive academic achievement gains for these students. These findings overlap with a second body of literature on culturally responsive instruction. Active gateway learning practices that emphasize interactive instruction, frequent assessment, and epistemological instruction can be successful because of their propensity to incorporate values affirming and utility-value techniques. The present study observed instruction for gateway STEM courses over a three-year period at the University of California, Irvine (N = 13,856 undergraduates in 168 courses). Exploratory polychoric factor analysis was used to identify latent variables for observational data on gateway STEM instructional practices. Variables were regressed on institutional student data. Practices implemented in large lecture halls fall into three general categories: Faculty-Student Interaction, Epistemological Instruction, and Peer Interaction . The present study found that Faculty-Student Interaction was negatively associated with student outcomes for

  9. Experimental test of 200 W Hall thruster with titanium wall

    Science.gov (United States)

    Ding, Yongjie; Sun, Hezhi; Peng, Wuji; Xu, Yu; Wei, Liqiu; Li, Hong; Li, Peng; Su, Hongbo; Yu, Daren

    2017-05-01

    We designed a 200 W Hall thruster based on the technology of pushing down a magnetic field with two permanent magnetic rings. Boron nitride (BN) is an important insulating wall material for Hall thrusters. The discharge characteristics of the designed Hall thruster were studied by replacing BN with titanium (Ti). Experimental results show that the designed Hall thruster can discharge stably for a long time under a Ti channel. Experiments were performed to determine whether the channel and cathode are electrically connected. When the channel wall and cathode are insulated, the divergence angle of the plume increases, but the performance of the Hall thruster is improved in terms of thrust, specific impulse, anode efficiency, and thrust-to-power ratio. Ti exhibits a powerful antisputtering capability, a low emanation rate of gas, and a large structural strength, making it a potential candidate wall material in the design of low-power Hall thrusters.

  10. Student-on-Student Harassment and Zero Tolerance: Achieving a Delicate Balance

    Science.gov (United States)

    Essex, Nathan L.

    2009-01-01

    Zero tolerance policy. Most school districts have a zero tolerance policy in place for drug use, weapons on campus, sexual harassment, or all of the above. At their very core, zero tolerance policies make schools safer. However, a one-size-fits-all approach does not work well in all situations involving student misconduct. This article outlines…

  11. Student Success through Leadership Self-Efficacy: A Comparison of International and Domestic Students

    Science.gov (United States)

    Nguyen, David H. K.

    2016-01-01

    There is scarce research that examines the leadership experiences of international students on campus. Leadership capacity and efficacy are important indicators of success in higher education and are linked to important academic, career, and life benefits, such as career and leadership aspirations, work performance, the ability to cope and…

  12. Students' drinking behavior and perceptions towards introducing alcohol policies on university campus in Denmark

    DEFF Research Database (Denmark)

    Larsen, Eva Ladekjær; Andsager Smorawski, Gitte; Lund Krabak, Katrine

    2016-01-01

    . The aim of this study is to explore students’ perceptions of alcohol policies on campus in relation to attitudes and practices of alcohol consumption. Methods We conducted six focus group interviews with students from the University of Southern Denmark at two different campuses. The interviews discussed...... topics such as experiences and attitudes towards alcohol consumption among students, regulations, and norms of alcohol use on campus. The analysis followed a pre-determined codebook. Results Alcohol consumption is an integrated practice on campus. Most of the participants found it unnecessary to make...... major restrictions. Instead, regulations were socially controlled by students themselves and related to what was considered to be appropriate behavior. However students were open minded towards smaller limitations of alcohol availability. These included banning the sale of alcohol in vending machines...

  13. Hall Sensor Output Signal Fault-Detection & Safety Implementation Logic

    Directory of Open Access Journals (Sweden)

    Lee SangHun

    2016-01-01

    Full Text Available Recently BLDC motors have been popular in various industrial applications and electric mobility. Recently BLDC motors have been popular in various industrial applications and electric mobility. In most brushless direct current (BLDC motor drives, there are three hall sensors as a position reference. Low resolution hall effect sensor is popularly used to estimate the rotor position because of its good comprehensive performance such as low cost, high reliability and sufficient precision. Various possible faults may happen in a hall effect sensor. This paper presents a fault-tolerant operation method that allows the control of a BLDC motor with one faulty hall sensor and presents the hall sensor output fault-tolerant control strategy. The situations considered are when the output from a hall sensor stays continuously at low or high levels, or a short-time pulse appears on a hall sensor signal. For fault detection, identification of a faulty signal and generating a substitute signal, this method only needs the information from the hall sensors. There are a few research work on hall effect sensor failure of BLDC motor. The conventional fault diagnosis methods are signal analysis, model based analysis and knowledge based analysis. The proposed method is signal based analysis using a compensation signal for reconfiguration and therefore fault diagnosis can be fast. The proposed method is validated to execute the simulation using PSIM.

  14. The Hall module of an exact category with duality

    OpenAIRE

    Young, Matthew B.

    2012-01-01

    We construct from a finitary exact category with duality a module over its Hall algebra, called the Hall module, encoding the first order self-dual extension structure of the category. We study in detail Hall modules arising from the representation theory of a quiver with involution. In this case we show that the Hall module is naturally a module over the specialized reduced sigma-analogue of the quantum Kac-Moody algebra attached to the quiver. For finite type quivers, we explicitly determin...

  15. DESIGN OF SUBSOIL IMPROVEMENT BELOW HALL FLOORS

    Directory of Open Access Journals (Sweden)

    Peter Turček

    2017-10-01

    Full Text Available The construction of an industrial park is now being prepared near the town of Nitra. The investor fixed very strict conditions for the bearing capacity and, above all, the settlement of halls and their floors. The geological conditions at the construction site are difficult: there are soft clay soils with high compressibility and low bearing capacity. A detailed analysis of soil improvement was made. Stone columns were prepared to be fitted into an approximately 5 m thick layer of soft clay. The paper shows the main steps used in the design of the stone columns.

  16. Optically induced Hall effect in semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Idrish Miah, M; Gray, E Mac A, E-mail: m.miah@griffith.edu.a [Nanoscale Science and Technology Centre, Griffith University, Nathan, Brisbane, QLD 4111 (Australia)

    2009-03-01

    We describe an experiment which investigates the effect of a longitudinal electric field on the spin-polarized carriers generated by a circularly polarized light in semiconductors. Our experiment observes the effect as a Hall voltage resulting from nonequilibrium magnetization induced by the spin-carrier electrons accumulating at the transverse boundaries of the sample as a result of asymmetries in scattering for spin-up and spin-down electrons in the presence of spin-orbit interaction. It is found that the effect depends on the longitudinal electric field and doping density as well as on temperature. The results are presented by discussing the dominant spin relaxation mechanisms in semiconductors.

  17. Fractional quantization and the quantum hall effect

    International Nuclear Information System (INIS)

    Guerrero, J.; Calixto, M.; Aldaya, V.

    1998-01-01

    Quantization with constrains is considered in a group-theoretical framework, providing a precise characterization of the set of good operators, i.e., those preserving the constrained Hilbert space, in terms of the representation of the subgroup of constraints. This machinery is applied to the quantization of the torus as symplectic manifold, obtaining that fractional quantum numbers are permitted, provided that we allow for vector valued representations. The good operators turn out to be the Wilson loops and, for certain representations of the subgroup of constraints, the modular transformations. These results are applied to the Fractional Quantum Hall Effect, where interesting implications are derived

  18. Excitons in the Fractional Quantum Hall Effect

    Science.gov (United States)

    Laughlin, R. B.

    1984-09-01

    Quasiparticles of charge 1/m in the Fractional Quantum Hall Effect form excitons, which are collective excitations physically similar to the transverse magnetoplasma oscillations of a Wigner crystal. A variational exciton wavefunction which shows explicitly that the magnetic length is effectively longer for quasiparticles than for electrons is proposed. This wavefunction is used to estimate the dispersion relation of these excitons and the matrix elements to generate them optically out of the ground state. These quantities are then used to describe a type of nonlinear conductivity which may occur in these systems when they are relatively clean.

  19. The fractional quantum Hall effect goes organic

    International Nuclear Information System (INIS)

    Smet, Jurgen

    2000-01-01

    Physicists have been fascinated by the behaviour of two-dimensional electron gases for the past two decades. All of these experiments were performed on inorganic semiconductor devices, most of them based on gallium arsenide. Indeed, until recently it was thought that the subtle effects that arise due to electron-electron interactions in these devices required levels of purity that could not be achieved in other material systems. However, Hendrik Schoen, Christian Kloc and Bertram Batlogg of Bell Laboratories in the US have now observed the fractional quantum Hall effect - the most dramatic signature of electron-electron interactions - in two organic semiconductors. (U.K.)

  20. A Compton polarimeter for CEBAF Hall A

    Energy Technology Data Exchange (ETDEWEB)

    Bardin, G; Cavata, C; Frois, B; Juillard, M; Kerhoas, S; Languillat, J C; Legoff, J M; Mangeot, P; Martino, J; Platchkov, S; Rebourgeard, P; Vernin, P; Veyssiere, C; CEBAF Hall A Collaboration

    1994-09-01

    The physic program at CEBAF Hall A includes several experiments using 4 GeV polarized electron beam: parity violation in electron elastic scattering from proton and {sup 4}He, electric form factor of the proton by recoil polarization, neutron spin structure function at low Q{sup 2}. Some of these experiments will need beam polarization measurement and monitoring with an accuracy close to 4%, for beam currents ranging from 100 nA to 100 microA. A project of a Compton Polarimeter that will meet these requirements is presented. It will comprise four dipoles and a symmetric cavity consisting of two identical mirrors. 1 fig., 10 refs.

  1. Hall conductivity for two dimensional magnetic systems

    International Nuclear Information System (INIS)

    Desbois, J.; Ouvry, S.; Texier, C.

    1996-01-01

    A Kubo inspired formalism is proposed to compute the longitudinal and transverse dynamical conductivities of an electron in a plane (or a gas of electrons at zero temperature) coupled to the potential vector of an external local magnetic field, with the additional coupling of the spin degree of freedom of the electron to the local magnetic field (Pauli Hamiltonian). As an example, the homogeneous magnetic field Hall conductivity is rederived. The case of the vortex at the origin is worked out in detail. A perturbative analysis is proposed for the conductivity in the random magnetic impurity problem (Poissonian vortices in the plane). (author)

  2. Transit-time instability in Hall thrusters

    International Nuclear Information System (INIS)

    Barral, Serge; Makowski, Karol; Peradzynski, Zbigniew; Dudeck, Michel

    2005-01-01

    Longitudinal waves characterized by a phase velocity of the order of the velocity of ions have been recurrently observed in Hall thruster experiments and simulations. The origin of this so-called ion transit-time instability is investigated with a simple one-dimensional fluid model of a Hall thruster discharge in which cold ions are accelerated between two electrodes within a quasineutral plasma. A short-wave asymptotics applied to linearized equations shows that plasma perturbations in such a device consist of quasineutral ion acoustic waves superimposed on a background standing wave generated by discharge current oscillations. Under adequate circumstances and, in particular, at high ionization levels, acoustic waves are amplified as they propagate, inducing strong perturbation of the ion density and velocity. Responding to the subsequent perturbation of the column resistivity, the discharge current generates a standing wave, the reflection of which sustains the generation of acoustic waves at the inlet boundary. A calculation of the frequency and growth rate of this resonance mechanism for a supersonic ion flow is proposed, which illustrates the influence of the ionization degree on their onset and the approximate scaling of the frequency with the ion transit time. Consistent with experimental reports, the traveling wave can be observed on plasma density and velocity perturbations, while the plasma potential ostensibly oscillates in phase along the discharge

  3. Cylindrical Hall Thrusters with Permanent Magnets

    International Nuclear Information System (INIS)

    Raitses, Yevgeny; Merino, Enrique; Fisch, Nathaniel J.

    2010-01-01

    The use of permanent magnets instead of electromagnet coils for low power Hall thrusters can offer a significant reduction of both the total electric power consumption and the thruster mass. Two permanent magnet versions of the miniaturized cylindrical Hall thruster (CHT) of different overall dimensions were operated in the power range of 50W-300 W. The discharge and plasma plume measurements revealed that the CHT thrusters with permanent magnets and electromagnet coils operate rather differently. In particular, the angular ion current density distribution from the permanent magnet thrusters has an unusual halo shape, with a majority of high energy ions flowing at large angles with respect to the thruster centerline. Differences in the magnetic field topology outside the thruster channel and in the vicinity of the channel exit are likely responsible for the differences in the plume characteristics measured for the CHTs with electromagnets and permanent magnets. It is shown that the presence of the reversing-direction or cusp-type magnetic field configuration inside the thruster channel without a strong axial magnetic field outside the thruster channel does not lead to the halo plasma plume from the CHT.

  4. Bimetric Theory of Fractional Quantum Hall States

    Directory of Open Access Journals (Sweden)

    Andrey Gromov

    2017-11-01

    Full Text Available We present a bimetric low-energy effective theory of fractional quantum Hall (FQH states that describes the topological properties and a gapped collective excitation, known as the Girvin-Macdonald-Platzman (GMP mode. The theory consists of a topological Chern-Simons action, coupled to a symmetric rank-2 tensor, and an action à la bimetric gravity, describing the gapped dynamics of a spin-2 mode. The theory is formulated in curved ambient space and is spatially covariant, which allows us to restrict the form of the effective action and the values of phenomenological coefficients. Using bimetric theory, we calculate the projected static structure factor up to the k^{6} order in the momentum expansion. To provide further support for the theory, we derive the long-wave limit of the GMP algebra, the dispersion relation of the GMP mode, and the Hall viscosity of FQH states. The particle-hole (PH transformation of the theory takes a very simple form, making the duality between FQH states and their PH conjugates manifest. We also comment on the possible applications to fractional Chern insulators, where closely related structures arise. It is shown that the familiar FQH observables acquire a curious geometric interpretation within the bimetric formalism.

  5. Hypernuclear Spectroscopy at JLab Hall C

    International Nuclear Information System (INIS)

    Hashimoto, Osamu; Chiba, Atsushi; Doi, Daisuke; Fujii, Yu; Toshiyuki, Gogami; Kanda, Hiroki; Kaneta, M.; Kawama, Daisuke; Maeda, Kazushige; Maruta, Tomofumi; Matsumura, Akihiko; Nagao, Sho; Nakamura, Satoshi; Shichijo, Ayako; Tamura, Hirokazu; Taniya, Naotaka; Yamamoto, Taku; Yokota, Kosuke; Kato, S.; Sato, Yoshinori; Takahashi, Toshiyuki; Noumi, Hiroyuki; Motoba, T.; Hiyama, E.; Albayrak, Ibrahim; Ates, Ozgur; Chen, Chunhua; Christy, Michael; Keppel, Cynthia; Kohl, Karl; Li, Ya; Liyanage, Anusha Habarakada; Tang, Liguang; Walton, T.; Ye, Zhihong; Yuan, Lulin; Zhu, Lingyan; Baturin, Pavlo; Boeglin, Werner; Dhamija, Seema; Markowitz, Pete; Raue, Brian; Reinhold, Joerg; Hungerford, Ed; Ent, Rolf; Fenker, Howard; Gaskell, David; Horn, Tanja; Jones, Mark; Smith, Gregory; Vulcan, William; Wood, Stephen; Johnston, C.; Simicevic, Neven; Wells, Stephen; Samanta, Chhanda; Hu, Bitao; Shen, Ji; Wang, W.; Zhang, Xiaozhuo; Zhang, Yi; Feng, Jing; Fu, Y.; Zhou, Jian; Zhou, S.; Jiang, Yi; Lu, H.; Yan, Xinhu; Ye, Yunxiu; Gan, Liping; Ahmidouch, Abdellah; Danagoulian, Samuel; Gasparian, Ashot; Elaasar, Mostafa; Wesselmann, Frank; Asaturyan, Arshak; Margaryan, Amur; Mkrtchyan, Arthur; Mkrtchyan, Hamlet; Tadevosyan, Vardan; Androic, Darko; Furic, Miroslav; Petkovic, Tomislav; Seva, Tomislav; Niculescu, Gabriel; Niculescu, Maria-Ioana; Rodriguez, Victor; Cisbani, Evaristo; Cusanno, Francesco; Garibaldi, Franco; Urciuoli, Guido; De Leo, Raffaele; Maronne, S.; Achenbach, Carsten; Pochodzalla, J.

    2010-01-01

    Since the 1st generation experiment, E89-009, which was successfully carried out as a pilot experiment of (e,e(prime)K + ) hypernuclear spectroscopy at JLab Hall C in 2000, precision hypernuclear spectroscopy by the (e,e(prime)K + ) reactions made considerable progress. It has evolved to the 2nd generation experiment, E01-011, in which a newly constructed high resolution kaon spectrometer (HKS) was installed and the 'Tilt method' was adopted in order to suppress large electromagnetic background and to run with high luminosity. Preliminary high-resolution spectra of 7 ΛHe and 28 ΛAl together with that of 12 ΛB that achieved resolution better than 500 keV(FWHM) were obtained. The third generation experiment, E05-115, has completed data taking with an experimental setup combining a new splitter magnet, high resolution electron spectrometer (HES) and the HKS used in the 2nd generation experiment. The data were accumulated with targets of 7 Li, 9 Be, 10 B, 12 C and 52 Cr as well as with those of CH 2 and H 2 O for calibration. The analysis is under way with particular emphasis of determining precision absolute hypernuclear masses. In this article, hypernuclear spectroscopy program in the wide mass range at JLab Hall C that has undergone three generation is described.

  6. Bimetric Theory of Fractional Quantum Hall States

    Science.gov (United States)

    Gromov, Andrey; Son, Dam Thanh

    2017-10-01

    We present a bimetric low-energy effective theory of fractional quantum Hall (FQH) states that describes the topological properties and a gapped collective excitation, known as the Girvin-Macdonald-Platzman (GMP) mode. The theory consists of a topological Chern-Simons action, coupled to a symmetric rank-2 tensor, and an action à la bimetric gravity, describing the gapped dynamics of a spin-2 mode. The theory is formulated in curved ambient space and is spatially covariant, which allows us to restrict the form of the effective action and the values of phenomenological coefficients. Using bimetric theory, we calculate the projected static structure factor up to the k6 order in the momentum expansion. To provide further support for the theory, we derive the long-wave limit of the GMP algebra, the dispersion relation of the GMP mode, and the Hall viscosity of FQH states. The particle-hole (PH) transformation of the theory takes a very simple form, making the duality between FQH states and their PH conjugates manifest. We also comment on the possible applications to fractional Chern insulators, where closely related structures arise. It is shown that the familiar FQH observables acquire a curious geometric interpretation within the bimetric formalism.

  7. Repurposing the Caltech Robinson Hall Coelostat

    Science.gov (United States)

    Treffers, Richard R.; Loisos, G.; Ubbelohde, M.; Douglas, S.; Martinez, M.

    2013-01-01

    We describe the repurposing of the historic coelostat atop Caltech’s Robinson Hall for building lighting, public education and scientific research. The coelostat was originally part of George Ellery Hale’s vision of the Astrophysical Laboratory on the Caltech campus in 1932. The coelostat, designed by Russell Porter, has a 36 inch diameter primary mirror a 30 inch diameter secondary mirror and provides a 24 inch un-vignetted beam of sunlight into the building. Although constructed in the 1930s, due to wartime pressures and other projects, it was used only briefly in the 1970s and never fully realized. Recently Robinson Hall has been fully renovated to house the Ronald and Maxine Linde Center for Global Environmental Science. The coelostat operation was modernized replacing the old motors and automating all the motions. Each morning, if the weather cooperates, the dome slit opens, the mirrors configured and sunlight pours into the building. The beam of sunlight is divided into three parts. One part goes into a refracting telescope which projects a ten inch diameter of the sun onto a ground glass screen visible to the public. A second fraction is distributed to fiber optic fixtures that illuminate some of the basement rooms. The final fraction goes into two laboratories where it is used in experiments monitoring trace constituents of our atmosphere and for solar catalysis experiments. The instrument as originally conceived required at least two human operators. Now it is fully automatic and doing real science

  8. Undulator Hall Air Temperature Fault Scenarios

    International Nuclear Information System (INIS)

    Sevilla, J.

    2010-01-01

    Recent experience indicates that the LCLS undulator segments must not, at any time following tuning, be allowed to change temperature by more than about ±2.5 C or the magnetic center will irreversibly shift outside of acceptable tolerances. This vulnerability raises a concern that under fault conditions the ambient temperature in the Undulator Hall might go outside of the safe range and potentially could require removal and retuning of all the segments. In this note we estimate changes that can be expected in the Undulator Hall air temperature for three fault scenarios: (1) System-wide power failure; (2) Heating Ventilation and Air Conditioning (HVAC) system shutdown; and (3) HVAC system temperature regulation fault. We find that for either a system-wide power failure or an HVAC system shutdown (with the technical equipment left on), the short-term temperature changes of the air would be modest due to the ability of the walls and floor to act as a heat ballast. No action would be needed to protect the undulator system in the event of a system-wide power failure. Some action to adjust the heat balance, in the case of the HVAC power failure with the equipment left on, might be desirable but is not required. On the other hand, a temperature regulation failure of the HVAC system can quickly cause large excursions in air temperature and prompt action would be required to avoid damage to the undulator system.

  9. An Opportunity to Lead Sustainably: The Benefits and Considerations of Student-Led Green Revolving Fund Projects

    Science.gov (United States)

    Kononenko, Kevin

    2012-01-01

    In recent years, energy- and resource-reduction projects have compelled student leaders to create sustainability projects on campuses across the country. This paper examines the role that students play in green revolving funds, including identification, approval, and management. After speaking with numerous students on a variety of campuses, it is…

  10. Administrative Challenge or Ethical Dilemma? Responding Justly when a Student with a Disability Engages in a Violent or Disruptive Act

    Science.gov (United States)

    Faircloth, Susan C.; Ritter, Suzanne T.; Wilson, Felicia R.

    2007-01-01

    This case study involves an 8-year-old American Indian student with a disability, who was videotaped assaulting another student as they exited the school bus. Although acts of school violence are common on campuses across the nation, this incident is particularly complex, given the disability status of the student committing this act. This case…

  11. The Interplay of Family Income, Campus Residency, and Student Retention (What Practitioners Should Know about Cultural Mismatch)

    Science.gov (United States)

    Schudde, Lauren

    2016-01-01

    Students from low-income families consistently trail behind their peers in retention and degree attainment. Research on college student experiences suggests that low-income students experience "cultural mismatch" at college--they feel that their backgrounds are at odds with the middle-class values dominant on campus (Armstrong &…

  12. Mary E. Hall: Dawn of the Professional School Librarian

    Science.gov (United States)

    Alto, Teresa

    2012-01-01

    A century ago, a woman named Mary E. Hall convinced school leaders of the need for the professional school librarian--a librarian who cultivated a love of reading, academic achievement, and independent learning skills. After graduating from New York City's Pratt Institute Library School in 1895, Hall developed her vision for the high school…

  13. What is the Hallé? | Smith | Philosophical Papers

    African Journals Online (AJOL)

    The bulk of the paper examines the difficulty of reconciling the view that the Hallé is several individuals with two prima facie plausible theses about the manner of its persistence through time. The paper is structured around some remarks made by Peter Simons about groups, and the Hallé in particular, in his Parts.

  14. Spin hall effect associated with SU(2) gauge field

    Science.gov (United States)

    Tao, Y.

    2010-01-01

    In this paper, we focus on the connection between spin Hall effect and spin force. Here we investigate that the spin force due to spin-orbit coupling, which, in two-dimensional system, is equivalent to forces of Hirsch and Chudnovsky besides constant factors 3 and frac{3}{2} respectively, is a part of classic Anandan force, and that the spin Hall effect is an anomalous Hall effect. Furthermore, we develop the method of AC phase to derive the expression for the spin force, and note that the most basic spin Hall effect indeed originate from the AC phase and is therefore an intrinsic quantum mechanical property of spin. This method differs from approach of Berry phase in the study of anomalous Hall effect , which is the intrinsic property of the perfect crystal. On the other hand, we use an elegant skill to show that the Chudnovsky-Drude model is reasonable. Here we have improved the theoretical values of spin Hall conductivity of Chudnovsky. Compared to the theoretical values of spin Hall conductivity in the Chudnovsky-Drude model, ours are in better agreement with experimentation. Finally, we discuss the relation between spin Hall effect and fractional statistics.

  15. Energy spectrum, dissipation, and spatial structures in reduced Hall magnetohydrodynamic

    Energy Technology Data Exchange (ETDEWEB)

    Martin, L. N.; Dmitruk, P. [Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires and IFIBA, CONICET, Ciudad Universitaria, 1428 Buenos Aires (Argentina); Gomez, D. O. [Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires and IFIBA, CONICET, Ciudad Universitaria, 1428 Buenos Aires (Argentina); Instituto de Astronomia y Fisica del Espacio, CONICET, Buenos Aires (Argentina)

    2012-05-15

    We analyze the effect of the Hall term in the magnetohydrodynamic turbulence under a strong externally supported magnetic field, seeing how this changes the energy cascade, the characteristic scales of the flow, and the dynamics of global magnitudes, with particular interest in the dissipation. Numerical simulations of freely evolving three-dimensional reduced magnetohydrodynamics are performed, for different values of the Hall parameter (the ratio of the ion skin depth to the macroscopic scale of the turbulence) controlling the impact of the Hall term. The Hall effect modifies the transfer of energy across scales, slowing down the transfer of energy from the large scales up to the Hall scale (ion skin depth) and carrying faster the energy from the Hall scale to smaller scales. The final outcome is an effective shift of the dissipation scale to larger scales but also a development of smaller scales. Current sheets (fundamental structures for energy dissipation) are affected in two ways by increasing the Hall effect, with a widening but at the same time generating an internal structure within them. In the case where the Hall term is sufficiently intense, the current sheet is fully delocalized. The effect appears to reduce impulsive effects in the flow, making it less intermittent.

  16. Quantifying Spin Hall Angles from Spin Pumping : Experiments and Theory

    NARCIS (Netherlands)

    Mosendz, O.; Pearson, J.E.; Fradin, F.Y.; Bauer, G.E.W.; Bader, S.D.; Hoffmann, A.

    2010-01-01

    Spin Hall effects intermix spin and charge currents even in nonmagnetic materials and, therefore, ultimately may allow the use of spin transport without the need for ferromagnets. We show how spin Hall effects can be quantified by integrating Ni80Fe20|normal metal (N) bilayers into a coplanar

  17. Stuart Hall on Racism and the Importance of Diasporic Thinking

    Science.gov (United States)

    Rizvi, Fazal

    2015-01-01

    In this article, I want to show how my initial encounter with the work of Stuart Hall was grounded in my reading of the later philosophy of Ludwig Wittgenstein, and was shaped by my interest in understanding the nature of racism across the three countries in which I had lived. Over the years, Hall's various writings have helped me to make sense of…

  18. Theory of the quantum hall effects in lattice systems

    International Nuclear Information System (INIS)

    Kliros, G.S.

    1990-06-01

    The Fractional Quantum Hall Effect is identified as an Integral Quantum Hall Effect of electrons on a lattice with an even number of statistical flux quanta. A variational wavefunction in terms of the Hofstadter lattice eigenstates is proposed. (author). 21 refs

  19. Bulk Versus Edge in the Quantum Hall Effect

    OpenAIRE

    Kao, Y. -C.; Lee, D. -H.

    1996-01-01

    The manifestation of the bulk quantum Hall effect on edge is the chiral anomaly. The chiral anomaly {\\it is} the underlying principle of the ``edge approach'' of quantum Hall effect. In that approach, $\\sxy$ should not be taken as the conductance derived from the space-local current-current correlation function of the pure one-dimensional edge problem.

  20. Critical current in the Integral Quantum Hall Effect

    International Nuclear Information System (INIS)

    Kostadinov, I.Z.

    1985-11-01

    A multiparticle theory of the Integral Quantum Hall Effect (IQHE) was constructed operating with pairs wave function as an order parameter. The IQHE is described with bosonic macroscopic states while the fractional QHE with fermionic ones. The calculation of the critical current and Hall conductivity temperature dependence is presented. (author)

  1. Useful Pedagogical Applications of the Classical Hall Effect

    Science.gov (United States)

    Houari, Ahmed

    2007-01-01

    One of the most known phenomena in physics is the Hall effect. This is mainly due to its simplicity and to the wide range of its theoretical and practical applications. To complete the pedagogical utility of the Hall effect in physics teaching, I will apply it here to determine the Faraday constant as a fundamental physical number and the number…

  2. A Novel Hall Effect Sensor Using Elaborate Offset Cancellation Method

    Directory of Open Access Journals (Sweden)

    Vlassis N. Petoussis

    2009-01-01

    Full Text Available The Hall effect is caused by a traverse force that is formed in the electrons or holes of metal element or semiconductor when are polarized by current source and simultaneously all the system it is found vertical in external magnetic field. Result is finally the production of difference of potential (Hall voltage in address vertical in that of current and magnetic field directions. In the present work is presented a new Hall sensor exploiting the former operation. In combination with his pioneering form and using dynamic spinning current technique with an elaborate sequence, it leads to satisfactory results of produced Hall voltage with small noise in a presence of external magnetic field. Anyone can see both the spinning current and anti-Hall technique in the same sensor simultaneously.

  3. Migrants and Their Experiences of Time: Edward T. Hall Revisited

    Directory of Open Access Journals (Sweden)

    Elisabeth Schilling

    2009-01-01

    Full Text Available In this paper we reassess the scientific heritage of Edward T. HALL and his contribution to the area of intercultural communication. The key objectives of our study are to demonstrate the applicability of HALL's theory of culture to empirical research and to establish its compatibility with other methods. Specifically, we propose that Alfred SCHÜTZ's phenomenology of sociality be taken as an extension to HALL. The connection between HALL and SCHÜTZ is made possible by the mutual emphases on the temporal dimension of culture and the temporal aspects of migration. With these foci we analyze six narratives by two groups of migrants: German and Russian. By combining HALL's theory of the cultural time with SCHÜTZ's phenomenological perspective on time and the Other and then applying them to empirical data, we show the terms in which different cultures experience time. URN: urn:nbn:de:0114-fqs0901357

  4. Unconventional quantum Hall effect in Floquet topological insulators

    KAUST Repository

    Tahir, M.

    2016-07-27

    We study an unconventional quantum Hall effect for the surface states of ultrathin Floquet topological insulators in a perpendicular magnetic field. The resulting band structure is modified by photon dressing and the topological property is governed by the low-energy dynamics of a single surface. An exchange of symmetric and antisymmetric surface states occurs by reversing the lights polarization. We find a novel quantum Hall state in which the zeroth Landau level undergoes a phase transition from a trivial insulator state, with Hall conductivity αyx = 0 at zero Fermi energy, to a Hall insulator state with αyx = e2/2h. These findings open new possibilities for experimentally realizing nontrivial quantum states and unusual quantum Hall plateaus at (±1/2,±3/2,±5/2, ...)e2/h. © 2016 IOP Publishing Ltd Printed in the UK.

  5. Magnetic Measurements of the Background Field in the Undulator Hall

    International Nuclear Information System (INIS)

    Fisher, Andrew

    2010-01-01

    The steel present in the construction of the undulator hall facility has the potential for changing the ambient fields present in the undulator hall. This note describes a measurement done to make a comparison between the fields in the hall and in the Magnetic Measurement Facility. In order for the undulators to have the proper tuning, the background magnetic field in the Undulator Hall should agree with the background field in the Magnetic Measurements Facility within .5 gauss. In order to verify that this was the case measurements were taken along the length of the undulator hall, and the point measurements were compared to the mean field which was measured on the MMF test bench.

  6. Unconventional quantum Hall effect in Floquet topological insulators

    KAUST Repository

    Tahir, M.; Vasilopoulos, P.; Schwingenschlö gl, Udo

    2016-01-01

    We study an unconventional quantum Hall effect for the surface states of ultrathin Floquet topological insulators in a perpendicular magnetic field. The resulting band structure is modified by photon dressing and the topological property is governed by the low-energy dynamics of a single surface. An exchange of symmetric and antisymmetric surface states occurs by reversing the lights polarization. We find a novel quantum Hall state in which the zeroth Landau level undergoes a phase transition from a trivial insulator state, with Hall conductivity αyx = 0 at zero Fermi energy, to a Hall insulator state with αyx = e2/2h. These findings open new possibilities for experimentally realizing nontrivial quantum states and unusual quantum Hall plateaus at (±1/2,±3/2,±5/2, ...)e2/h. © 2016 IOP Publishing Ltd Printed in the UK.

  7. Students' drinking behavior and perceptions towards introducing alcohol policies on university campus in Denmark: a focus group study.

    Science.gov (United States)

    Ladekjær Larsen, Eva; Smorawski, Gitte Andsager; Kragbak, Katrine Lund; Stock, Christiane

    2016-04-29

    High alcohol consumption among university students is a well-researched health concern in many countries. At universities in Denmark, policies of alcohol consumption are a new phenomenon if existing at all. However, little is known of how students perceive campus alcohol policies. The aim of this study is to explore students' perceptions of alcohol policies on campus in relation to attitudes and practices of alcohol consumption. We conducted six focus group interviews with students from the University of Southern Denmark at two different campuses. The interviews discussed topics such as experiences and attitudes towards alcohol consumption among students, regulations, and norms of alcohol use on campus. The analysis followed a pre-determined codebook. Alcohol consumption is an integrated practice on campus. Most of the participants found it unnecessary to make major restrictions. Instead, regulations were socially controlled by students themselves and related to what was considered to be appropriate behavior. However students were open minded towards smaller limitations of alcohol availability. These included banning the sale of alcohol in vending machines and limiting consumption during the introduction week primarily due to avoiding social exclusion of students who do not drink. Some international students perceived the level of consumption as too high and distinguished between situations where they perceived drinking as unusual. The study showed that alcohol is a central part of students' lives. When developing and implementing alcohol policies on campus, seeking student input in the process and addressing alcohol policies in the larger community will likely improve the success of the policies.

  8. Introducing Research Methods to Undergraduate Majors Through an On-Campus Observatory with The University of Toledo's Ritter Observatory

    Science.gov (United States)

    Richardson, Noel; Hardegree-Ullman, Kevin; Bjorkman, Jon Eric; Bjorkman, Karen S.; Ritter Observing Team

    2017-01-01

    With a 1-m telescope on the University of Toledo (OH) main campus, we have initiated a grad student-undergraduate partnership to help teach the undergraduates observational methods and introduce them to research through peer mentorship. For the last 3 years, we have trained up to 21 undergraduates (primarily physics/astronomy majors) in a given academic semester, ranging from freshman to seniors. Various projects are currently being conducted by undergraduate students with guidance from graduate student mentors, including constructing three-color images, observations of transiting exoplanets, and determination of binary star orbits from echelle spectra. This academic year we initiated a large group research project to help students learn about the databases, journal repositories, and online observing tools astronomers use for day-to-day research. We discuss early inclusion in observational astronomy and research of these students and the impact it has on departmental retention, undergraduate involvement, and academic success.

  9. Planar Hall Effect Sensors for Biodetection

    DEFF Research Database (Denmark)

    Rizzi, Giovanni

    . In the second geometry (dPHEB) half of the sensor is used as a local negative reference to subtract the background signal from magnetic beads in suspension. In all applications below, the magnetic beads are magnetised using the magnetic field due to the bias current passed through the sensor, i.e., no external...... as labels and planar Hall effect bridge (PHEB) magnetic field sensor as readout for the beads. The choice of magnetic beads as label is motivated by the lack of virtually any magnetic background from biological samples. Moreover, magnetic beads can be manipulated via an external magnetic field...... hybridisation in real-time, in a background of suspended magnetic beads. This characteristic is employed in single nucleotide polymorphism (SNP) genotyping, where the denaturation of DNA is monitored in real-time upon washing with a stringency buffer. The sensor setup includes temperature control and a fluidic...

  10. Numerical investigation of a Hall thruster plasma

    International Nuclear Information System (INIS)

    Roy, Subrata; Pandey, B.P.

    2002-01-01

    The dynamics of the Hall thruster is investigated numerically in the framework of a one-dimensional, multifluid macroscopic description of a partially ionized xenon plasma using finite element formulation. The model includes neutral dynamics, inelastic processes, and plasma-wall interaction. Owing to disparate temporal scales, ions and neutrals have been described by set of time-dependent equations, while electrons are considered in steady state. Based on the experimental observations, a third order polynomial in electron temperature is used to calculate ionization rate. The results show that in the acceleration channel the increase in the ion number density is related to the decrease in the neutral number density. The electron and ion velocity profiles are consistent with the imposed electric field. The electron temperature remains uniform for nearly two-thirds of the channel; then sharply increases to a peak before dropping slightly at the exit. This is consistent with the predicted electron gyration velocity distribution

  11. Quantum Hall effect on Riemann surfaces

    Science.gov (United States)

    Tejero Prieto, Carlos

    2009-06-01

    We study the family of Landau Hamiltonians compatible with a magnetic field on a Riemann surface S by means of Fourier-Mukai and Nahm transforms. Starting from the geometric formulation of adiabatic charge transport on Riemann surfaces, we prove that Hall conductivity is proportional to the intersection product on the first homology group of S and therefore it is quantized. Finally, by using the theory of determinant bundles developed by Bismut, Gillet and Soul, we compute the adiabatic curvature of the spectral bundles defined by the holomorphic Landau levels. We prove that it is given by the polarization of the jacobian variety of the Riemann surface, plus a term depending on the relative analytic torsion.

  12. Quantum Hall effect on Riemann surfaces

    International Nuclear Information System (INIS)

    Tejero Prieto, Carlos

    2009-01-01

    We study the family of Landau Hamiltonians compatible with a magnetic field on a Riemann surface S by means of Fourier-Mukai and Nahm transforms. Starting from the geometric formulation of adiabatic charge transport on Riemann surfaces, we prove that Hall conductivity is proportional to the intersection product on the first homology group of S and therefore it is quantized. Finally, by using the theory of determinant bundles developed by Bismut, Gillet and Soul, we compute the adiabatic curvature of the spectral bundles defined by the holomorphic Landau levels. We prove that it is given by the polarization of the jacobian variety of the Riemann surface, plus a term depending on the relative analytic torsion.

  13. Frequency spectrum of Calder Hall reactor noise

    International Nuclear Information System (INIS)

    Cummins, J.D.

    1960-01-01

    The frequency spectrum of the noise power of Calder Hall reactor No. 1 has been obtained by analysing a tape recording of the backed off power. The root mean square noise power due to all frequencies above 0.001 cycles per second was found to be 0.13%. The noise power for this reactor, is due mainly to modulations of the power level by reactivity variations caused in turn by gas temperature changes. These gas temperature changes are caused by a Cyclic variation in the feedwater regulator to the heat exchanger. The apparatus and method used to determine the noise power are described in this memorandum. It is shown that for frequencies in the range 0.001 to 0.030 cycles per second the noise spectrum falls at 60 decibels per decade of frequency. (author)

  14. OPTICS. Quantum spin Hall effect of light.

    Science.gov (United States)

    Bliokh, Konstantin Y; Smirnova, Daria; Nori, Franco

    2015-06-26

    Maxwell's equations, formulated 150 years ago, ultimately describe properties of light, from classical electromagnetism to quantum and relativistic aspects. The latter ones result in remarkable geometric and topological phenomena related to the spin-1 massless nature of photons. By analyzing fundamental spin properties of Maxwell waves, we show that free-space light exhibits an intrinsic quantum spin Hall effect—surface modes with strong spin-momentum locking. These modes are evanescent waves that form, for example, surface plasmon-polaritons at vacuum-metal interfaces. Our findings illuminate the unusual transverse spin in evanescent waves and explain recent experiments that have demonstrated the transverse spin-direction locking in the excitation of surface optical modes. This deepens our understanding of Maxwell's theory, reveals analogies with topological insulators for electrons, and offers applications for robust spin-directional optical interfaces. Copyright © 2015, American Association for the Advancement of Science.

  15. Determination of the Hall Thruster Operating Regimes

    International Nuclear Information System (INIS)

    L. Dorf; V. Semenov; Y. Raitses; N.J. Fisch

    2002-04-01

    A quasi one-dimensional (1-D) steady-state model of the Hall thruster is presented. For the same discharge voltage two operating regimes are possible -- with and without the anode sheath. For given mass flow rate, magnetic field profile and discharge voltage a unique solution can be constructed, assuming that the thruster operates in one of the regimes. However, we show that for a given temperature profile the applied discharge voltage uniquely determines the operating regime: for discharge voltages greater than a certain value, the sheath disappears. That result is obtained over a wide range of incoming neutral velocities, channel lengths and widths, and cathode plane locations. It is also shown that a good correlation between the quasi 1-D model and experimental results can be achieved by selecting an appropriate electron mobility and temperature profile

  16. Chaotic waves in Hall thruster plasma

    International Nuclear Information System (INIS)

    Peradzynski, Zbigniew; Barral, S.; Kurzyna, J.; Makowski, K.; Dudeck, M.

    2006-01-01

    The set of hyperbolic equations of the fluid model describing the acceleration of plasma in a Hall thruster is analyzed. The characteristic feature of the flow is the existence of a trapped characteristic; i.e. there exists a characteristic line, which never intersects the boundary of the flow region in the thruster. To study the propagation of short wave perturbations, the approach of geometrical optics (like WKB) can be applied. This can be done in a linear as well as in a nonlinear version. The nonlinear version describes the waves of small but finite amplitude. As a result of such an approach one obtains so called transport equation, which are governing the wave amplitude. Due to the existence of trapped characteristics this transport equation appears to have chaotic (turbulent) solutions in both, linear and nonlinear versions

  17. Spin Hall magnetoresistance at high temperatures

    International Nuclear Information System (INIS)

    Uchida, Ken-ichi; Qiu, Zhiyong; Kikkawa, Takashi; Iguchi, Ryo; Saitoh, Eiji

    2015-01-01

    The temperature dependence of spin Hall magnetoresistance (SMR) in Pt/Y 3 Fe 5 O 12 (YIG) bilayer films has been investigated in a high temperature range from room temperature to near the Curie temperature of YIG. The experimental results show that the magnitude of the magnetoresistance ratio induced by the SMR monotonically decreases with increasing the temperature and almost disappears near the Curie temperature. We found that, near the Curie temperature, the temperature dependence of the SMR in the Pt/YIG film is steeper than that of a magnetization curve of the YIG; the critical exponent of the magnetoresistance ratio is estimated to be 0.9. This critical behavior of the SMR is attributed mainly to the temperature dependence of the spin-mixing conductance at the Pt/YIG interface

  18. Concept of Operating Indoor Skiing Halls with

    DEFF Research Database (Denmark)

    Paul, Joachim

    2003-01-01

    Indoor skiing halls are conventionally operated at low temperatures and with either crushed ice as snow substitute or snow made from freezing water in cold air. Both systems have a high energy demand for air cooling, floor freezing and consequently snow harvest. At the same time the snow at the top...... floor cooling/freezing and insulation become obsolete, significant savings in piping and building costs can be achieved. Due to the much higher evaporating temperature for the refrigeration system, the energy demand is kept low. Since the same equipment is used for both snowmaking and air cooling......, the running time of the equipment is high, resulting in a better economy. Using Binary Snow, with its unique qualities such as fluffy, crisp, white and ¿ since made daily ¿ "fresh and hygienic", offers great advantages in operating costs, investment costs and quality....

  19. Geometrical Description of fractional quantum Hall quasiparticles

    Science.gov (United States)

    Park, Yeje; Yang, Bo; Haldane, F. D. M.

    2012-02-01

    We examine a description of fractional quantum Hall quasiparticles and quasiholes suggested by a recent geometrical approach (F. D. M. Haldane, Phys. Rev. Lett. 108, 116801 (2011)) to FQH systems, where the local excess electric charge density in the incompressible state is given by a topologically-quantized ``guiding-center spin'' times the Gaussian curvature of a ``guiding-center metric tensor'' that characterizes the local shape of the correlation hole around electrons in the fluid. We use a phenomenological energy function with two ingredients: the shear distortion energy of area-preserving distortions of the fluid, and a local (short-range) approximation to the Coulomb energy of the fluctuation of charge density associated with the Gaussian curvature. Quasiparticles and quasiholes of the 1/3 Laughlin state are modeled as ``punctures'' in the incompressible fluid which then relax by geometric distortion which generates Gaussian curvature, giving rise to the charge-density profile around the topological excitation.

  20. Cathode Effects in Cylindrical Hall Thrusters

    Energy Technology Data Exchange (ETDEWEB)

    Granstedt, E.M.; Raitses, Y.; Fisch, N. J.

    2008-09-12

    Stable operation of a cylindrical Hall thruster (CHT) has been achieved using a hot wire cathode, which functions as a controllable electron emission source. It is shown that as the electron emission from the cathode increases with wire heating, the discharge current increases, the plasma plume angle reduces, and the ion energy distribution function shifts toward higher energies. The observed effect of cathode electron emission on thruster parameters extends and clarifies performance improvements previously obtained for the overrun discharge current regime of the same type of thruster, but using a hollow cathode-neutralizer. Once thruster discharge current saturates with wire heating, further filament heating does not affect other discharge parameters. The saturated values of thruster discharge parameters can be further enhanced by optimal placement of the cathode wire with respect to the magnetic field.

  1. On-Chip Microwave Quantum Hall Circulator

    Directory of Open Access Journals (Sweden)

    A. C. Mahoney

    2017-01-01

    Full Text Available Circulators are nonreciprocal circuit elements that are integral to technologies including radar systems, microwave communication transceivers, and the readout of quantum information devices. Their nonreciprocity arises from the interference of microwaves over the centimeter scale of the signal wavelength, in the presence of bulky magnetic media that breaks time-reversal symmetry. Here, we realize a completely passive on-chip microwave circulator with size 1/1000th the wavelength by exploiting the chiral, “slow-light” response of a two-dimensional electron gas in the quantum Hall regime. For an integrated GaAs device with 330  μm diameter and about 1-GHz center frequency, a nonreciprocity of 25 dB is observed over a 50-MHz bandwidth. Furthermore, the nonreciprocity can be dynamically tuned by varying the voltage at the port, an aspect that may enable reconfigurable passive routing of microwave signals on chip.

  2. Mesoscopic spin Hall effect in semiconductor nanostructures

    Science.gov (United States)

    Zarbo, Liviu

    The spin Hall effect (SHE) is a name given to a collection of diverse phenomena which share two principal features: (i) longitudinal electric current flowing through a paramagnetic semiconductor or metallic sample leads to transverse spin current and spin accumulation of opposite sign at opposing lateral edges; (ii) SHE does not require externally applied magnetic field or magnetic ordering in the equilibrium state of the sample, instead it relies on the presence of spin-orbit (SO) couplings within the sample. This thesis elaborates on a new type of phenomenon within the SHE family, predicted in our recent studies [Phys. Rev. B 72, 075361 (2005); Phys. Rev. Lett. 95, 046601 (2005); Phys. Rev. B 72, 075335 (2005); Phys. Rev. B 73 , 075303 (2006); and Europhys. Lett. 77, 47004 (2007)], where pure spin current flows through the transverse electrodes attached to a clean finitesize two-dimensional electron gas (2DEG) due to unpolarized charge current injected through its longitudinal leads. If transverse leads are removed, the effect manifests as nonequilibrium spin Hall accumulation at the lateral edges of 2DEG wires. The SO coupling driving this SHE effect is of the Rashba type, which arises due to structural inversion asymmetry of semiconductor heterostructure hosting the 2DEG. We term the effect "mesoscopic" because the spin Hall currents and accumulations reach optimal value in samples of the size of the spin precession length---the distance over which the spin of an electron precesses by an angle pi. In strongly SO-coupled structures this scale is of the order of ˜100 nm, and, therefore, mesoscopic in the sense of being much larger than the characteristic microscopic scales (such as the Fermi wavelength, screening length, or the mean free path in disordered systems), but still much smaller than the macroscopic ones. Although the first theoretical proposal for SHE, driven by asymmetry in SO-dependent scattering of spin-up and spin-down electrons off impurities

  3. 50 KW Class Krypton Hall Thruster Performance

    Science.gov (United States)

    Jacobson, David T.; Manzella, David H.

    2003-01-01

    The performance of a 50-kilowatt-class Hall thruster designed for operation on xenon propellant was measured using kryton propellant. The thruster was operated at discharge power levels ranging from 6.4 to 72.5 kilowatts. The device produced thrust ranging from 0.3 to 2.5 newtons. The thruster was operated at discharge voltages between 250 and 1000 volts. At the highest anode mass flow rate and discharge voltage and assuming a 100 percent singly charged condition, the discharge specific impulse approached the theoretical value. Discharge specific impulse of 4500 seconds was demonstrated at a discharge voltage of 1000 volts. The peak discharge efficiency was 64 percent at 650 volts.

  4. Magnon Hall effect on the Lieb lattice.

    Science.gov (United States)

    Cao, Xiaodong; Chen, Kai; He, Dahai

    2015-04-29

    Ferromagnetic insulators without inversion symmetry may show magnon Hall effect (MHE) in the presence of a temperature gradient due to the existence of Dzyaloshinskii-Moriya interaction (DMI). In this theoretical study, we investigate MHE on a lattice with inversion symmetry, namely the Lieb lattice, where the DMI is introduced by adding an external electric field. We show the nontrivial topology of this model by examining the existence of edge states and computing the topological phase diagram characterized by the Chern numbers of different bands. Together with the topological phase diagram, we can further determine the sign and magnitude of the transverse thermal conductivity. The impact of the flat band possessed by this model on the thermal conductivity is discussed by computing the Berry curvature analytically.

  5. Photonic spin Hall effect at metasurfaces.

    Science.gov (United States)

    Yin, Xiaobo; Ye, Ziliang; Rho, Junsuk; Wang, Yuan; Zhang, Xiang

    2013-03-22

    The spin Hall effect (SHE) of light is very weak because of the extremely small photon momentum and spin-orbit interaction. Here, we report a strong photonic SHE resulting in a measured large splitting of polarized light at metasurfaces. The rapidly varying phase discontinuities along a metasurface, breaking the axial symmetry of the system, enable the direct observation of large transverse motion of circularly polarized light, even at normal incidence. The strong spin-orbit interaction deviates the polarized light from the trajectory prescribed by the ordinary Fermat principle. Such a strong and broadband photonic SHE may provide a route for exploiting the spin and orbit angular momentum of light for information processing and communication.

  6. Assessing Attitudes Towards Science During an Adaptive Online Astrobiology Course: Comparing Online and On-Campus Undergraduates

    Science.gov (United States)

    Perera, Viranga; Mead, Chris; Buxner, Sanlyn; Horodyskyj, Lev; Semken, Steven; Lopatto, David; Anbar, Ariel

    2016-10-01

    General-education Science, Technology, Engineering, and Mathematics (STEM) courses are accepted as essential to a college education. An often cited reason is to train a scientifically literate populace who can think critically and make informed decisions about complex issues such as climate change, health care, and atomic energy. Goals of these STEM courses, therefore, go beyond content knowledge to include generating positive attitudes towards science, developing competence in evaluating scientific information in everyday life and understanding the nature of science. To gauge if such non-content learning outcomes are being met in our course, an online astrobiology course called Habitable Worlds, we administered the Classroom Undergraduate Research Experience (CURE) survey to students. The survey was administered before and after completion of the course for three semesters starting with the Fall 2014 semester and ending with the Fall 2015 semester (N = 774). A factor analysis indicated three factors on attitudes: toward science education, toward the interconnectedness of science with non-science fields, and toward the nature of science. Here we present some differences between students enrolled in online degree programs (o-course) and those enrolled in traditional undergraduate programs (i-course). While mean course grades were similar, changes in attitudes toward science differ significantly between o-course and i-course students. The o-course students began the course with more positive attitudes across all three factors than the i-course students. Their attitudes toward science education improved during the course, while the i-course students showed no change. Attitudes toward the other two factors declined in both populations during the course, but declines were smaller among o-course students. These differences may indicate lesser intrinsic motivation among the i-course students. The CURE survey has not been used before in an online course; therefore, we will

  7. Nonadiabatic effects in the Quantum Hall regime

    International Nuclear Information System (INIS)

    Page, D.A.; Brown, E.

    1993-01-01

    The authors consider the effect of a finite electric field on the states of a Bloch electron in two dimensions, with a uniform magnetic field present. They make use of the concept of electric time translation symmetry and treat the electric and magnetic fields symmetrically in a time dependent formalism. In addition to a wave vector k, the states are characterized by a frequency specifying the behavior under electric time translations. An effective Hamiltonian is employed to obtain the splitting of an isolated Bloch band into open-quotes frequencyclose quotes subbands. The time-averaged velocity and energy of the states are expressed in terms of the frequency dispersion. The relationship to the Stark ladder eigenstates in a scalar potential representation of the electric field is examined. This is seen to justify the use of the averaged energy in determining occupation of the states. In the weak electric field (adiabatic) limit, an expression is recovered for the quantized Hall conductivity of a magnetic subband as a topological invariant. A numerical procedure is outlined and results obtained over a range of electric field strengths. A transition between strong and weak field regimes is seen, with level repulsions between the frequencies playing an important role. The numerical results show how the magnetic subband structure and quantized Hall conductivity emerge as the electric field becomes weaker. In this regime, the behavior can be understood by comparison to the predictions of the adiabatic approximation. The latter predicts crossings in the frequencies at certain locations in wave vector space. Nonadiabatic effects are seen to produce gaps in the frequency spectrum at these locations. 35 refs., 14 figs

  8. Canadian Campus Smoking Policies: Investigating the Gap between Intent and Outcome from a Student Perspective

    Science.gov (United States)

    Baillie, Lynne; Callaghan, Doris; Smith, Michelle L.

    2011-01-01

    Background: Young adults remain the earliest legal target for the tobacco industry. Against this, the existence of smoking policies would appear to offer some protection to students on campus. However, little research has been conducted into the outcomes of such policies from a student perspective. Methods: The authors conducted 8 focus groups at…

  9. Racialization: The Experiences of Muslim Graduate Students in Higher Education after September 11

    Science.gov (United States)

    Naji Amrani, Imane

    2017-01-01

    The need to understand how Muslim students experience college is a growing concern, given the number of incidents that indicate a hostile environment after the events of September 11, and the subsequent war against terror. Muslim graduate students are more visible on campuses across the United States. This study examines the experiences of Muslim…

  10. "It's More Than a Class": Leisure Education's Influence on College Student Engagement

    Science.gov (United States)

    Evans, Kate E.; Hartman, Cindy L.; Anderson, Denise M.

    2013-01-01

    As universities and colleges continue to seek out ways to improve student engagement on their campuses, attention has been given to the role that on-campus leisure opportunities can play in developing this engagement. Yet, little research has analyzed the influence of leisure education on student engagement in the higher education setting. The…

  11. Factors to Consider When Balancing Campus Safety Concerns with Students' Civil Rights

    Science.gov (United States)

    Ingersoll, Julia S.

    2017-01-01

    On April 16, 2007, a student at Virginia Tech University, known to be mentally ill, went on a rampage shooting 49 people on campus before taking his own life. When it was over, 32 people were dead, and the concept of a safe campus was forever changed. The incident revealed the inherent conflicts between campus safety concerns and students' civil…

  12. Does Living near Classmates Help Introductory Economics Students Get Better Grades?

    Science.gov (United States)

    Parker, Jeffrey

    2012-01-01

    This article examines whether first-year students in introductory economics courses get better grades if they have other students in their on-campus residential unit who either are taking the same course or have taken the course in the past. The study uses nine years of data for the introductory economics course at Reed College. The author finds…

  13. Career Aspirations and the First Generation Student: Unraveling the Layers with Social Cognitive Career Theory

    Science.gov (United States)

    Raque-Bogdan, Trisha L.; Lucas, Margaretha S.

    2016-01-01

    Undergraduate students who are the first in their immediate family to go to college represent a unique population on campus deserving special attention to their educational and career development needs. We explored career development characteristics of first-generation college students and compared them to those who are not first-generation, using…

  14. College Students' Experiences with Anonymous Social Media: Implications for Campus Racial Climate

    Science.gov (United States)

    Armstrong, Amanda; Thomas, Jaymi; Smith, Madeline

    2017-01-01

    The purpose of this exploratory case study was to gather undergraduate students' perceptions of anonymous racist messages found on Yik Yak and to better understand the implications of anonymous platforms on campus racial climate. Given the limited research surrounding students' use of anonymous social media platforms, as well as the predominant…

  15. Measurement and Evidence of Computer-Based Task Switching and Multitasking by "Net Generation" Students

    Science.gov (United States)

    Judd, Terry; Kennedy, Gregor

    2011-01-01

    Logs of on-campus computer and Internet usage were used to conduct a study of computer-based task switching and multitasking by undergraduate medical students. A detailed analysis of over 6000 individual sessions revealed that while a majority of students engaged in both task switching and multitasking behaviours, they did so less frequently than…

  16. Emerging Themes of Student Satisfaction in a Traditional Course and a Blended Distance Course.

    Science.gov (United States)

    Parkinson, Debra; Greene, William; Kim, Younghee; Marioni, Joan

    2003-01-01

    Describes a team research project that explored and compared students' satisfaction with course delivery methods (blended distance learning with a remote site and an on-campus site, and a traditional section) based on the students' learning preferences. Explains research methodology used and results from the current study, and provides…

  17. The Role of Student Affairs Practitioners in Improving Campus Racial Climate: A Case Study

    Science.gov (United States)

    Karkouti, Ibrahim Mohamad

    2015-01-01

    The purpose of this paper is to examine the racial conflict that occurred at the University of Michigan (UMI) earlier last year when Black students expressed their frustrations with the underrepresentation, racial discrimination and disparaging remarks against African Americans on campus (Jaschik, 2014). Because student affairs is the service most…

  18. Mental Health Need, Awareness, and Use of Counseling Services among International Graduate Students

    Science.gov (United States)

    Hyun, Jenny; Quinn, Brian; Madon, Temina; Lustig, Steve

    2007-01-01

    Objective and Participants: The authors examined the prevalence of mental health needs in international graduate students, their knowledge of mental health services, and their use of on-campus and off-campus counseling services. Methods: All registered graduate students in the Spring 2004 semester received an e-mail invitation to participate in a…

  19. Factors Related to the Number of Fast Food Meals Obtained by College Meal Plan Students

    Science.gov (United States)

    Dingman, Deirdre A.; Schulz, Mark R.; Wyrick, David L.; Bibeau, Daniel L.; Gupta, Sat N.

    2014-01-01

    Objectives: This study tested whether days on campus, financial access through a meal plan, and health consciousness were associated with number of meals that college students obtained from fast food restaurants. Participants and Methods: In April 2013, all students currently enrolled in a meal plan were invited to participate in an online survey…

  20. Money Worries Keep Students Going to Campus Food Banks

    Science.gov (United States)

    Sandoval, Timothy

    2012-01-01

    Hunger on campus is part of a lingering national problem that grew after the financial crisis that began in late 2007. In an unforgiving economy, many students across the country struggle not only to pay tuition but also to buy food. Colleges and nonprofit groups have noticed, and more are reacting. Food pantries are cropping up on two-year and…

  1. The Zimbabwe student movement: Love-hate relationship with ...

    African Journals Online (AJOL)

    imposed by ESAP resulted in financial problems and poverty for students. Confrontation .... In November. 1953, Dr William Rollo, formerly Professor of Classics at the University of Cape Town, ... signified a moral outrage and moral pressures affecting society. Authorities ..... disrupted normal business on campus. Indeed, in ...

  2. Student Perceptions of Campus Cultural Climate by Race.

    Science.gov (United States)

    Ancis, Julie R.; Sedlacek, William E.; Mohr, Jonathan J.

    2000-01-01

    Reports on questionnaire about perceptions and experiences distributed to African American, Asian American, Latino/a, and White undergraduates. African Americans reported more racial-ethnic conflict on campus, more pressure to conform to stereotypes, and less equitable treatment by faculty and teaching assistants. White students' responses…

  3. Gaming Worlds: Secondary Students Creating An Interactive Video Game

    Science.gov (United States)

    Alexander, Amanda; Ho, Tuan

    2015-01-01

    Since the summer of 2006, the University of Texas at Arlington (UTA), in the Dallas/Ft. Worth metroplex, has invited secondary students to participate in their summer SEED program on campus. The program was developed by the Dean of the School of Architecture and the Chair of the Art + Art History Department. SEED (Strategies, Events, Episodes +…

  4. How Should We "Care" for LGBT+ Students within Higher Education?

    Science.gov (United States)

    Formby, Eleanor

    2017-01-01

    This article draws on a recent U.K. research project about lesbian, gay, bisexual and trans (LGBT+) perspectives on university to examine the implications for pastoral care and other service provision on campus. In a departure from previous scholarship that has tended to understand LGBT+ students as "vulnerable" and/or needing…

  5. AIDS fatigue and university students' talk about HIV risk | Shefer ...

    African Journals Online (AJOL)

    The findings demonstrate the gap between reported HIV-prevention knowledge and safer-sex practices among a group of young and educated South Africans. Although the participants reported that students were knowledgeable about HIV and had easy access to condoms on campus, a range of factors mediated their ...

  6. Medical Student Views on Interactions with Pharmaceutical Representatives

    Science.gov (United States)

    Ganzini, Linda; Chen, Zunqiu; Peters, Dawn; Misra, Sahana; Macht, Madison; Osborne, Molly; Keepers, George

    2012-01-01

    Objective: In 2006, the Housestaff Association presented the Dean at Oregon Health and Science University (OHSU) with a proposal to effectively end the influence of the pharmaceutical industry on campus. The Dean convened a workgroup to examine the issue, and faculty, residents, and medical students were surveyed on their views and interactions.…

  7. Multiracial Women Students and Racial Stereotypes on the College Campus

    Science.gov (United States)

    Harris, Jessica C.

    2017-01-01

    Researchers have explored how multiracial women students encounter different racialized experiences when compared to their monoracial peers and multiracial men on campus, suggesting that their experiences with racial stereotypes may also diverge from both of these populations. Guided by critical race theory, in this study I explored 10 multiracial…

  8. Temperature dependence of collapse of quantized hall resistance

    International Nuclear Information System (INIS)

    Tanaka, Hiroyasu; Kawashima, Hironori; Iizuka, Hisamitsu; Fukuda, Hideaki; Kawaji, Shinji

    2006-01-01

    Similarity is observed in the deviation of Hall resistance from the quantized value with the increase in the source-drain current I SD in our butterfly-type Hall bars and in the Hall bars used by Jeanneret et al., while changes in the diagonal resistivity ρ xx with I SD are significantly different between these Hall bars. The temperature dependence of the critical Hall electric field F cr (T) for the collapse of R H (4) measured in these Hall bars is approximated using F cr (T) = F cr (0)(1 - (T/T cr ) 2 ). Here, the critical Hall electric field at zero temperature depends on the magnetic field B as F cr (0) ∝ B 3/2 . Theoretical considerations are given on F cr (T) on the basis of a temperature-dependent mobility edge model and a schema of temperature-dependent inter-Landau level tunneling probability arising from the Fermi distribution function. The former does not fit in with the I SD dependence of activation energy in ρ xx . (author)

  9. Spontaneous Hall effect in a chiral p-wave superconductor

    Science.gov (United States)

    Furusaki, Akira; Matsumoto, Masashige; Sigrist, Manfred

    2001-08-01

    In a chiral superconductor with broken time-reversal symmetry a ``spontaneous Hall effect'' may be observed. We analyze this phenomenon by taking into account the surface properties of a chiral superconductor. We identify two main contributions to the spontaneous Hall effect. One contribution originates from the Bernoulli (or Lorentz) force due to spontaneous currents running along the surfaces of the superconductor. The other contribution has a topological origin and is related to the intrinsic angular momentum of Cooper pairs. The latter can be described in terms of a Chern-Simons-like term in the low-energy field theory of the superconductor and has some similarities with the quantum Hall effect. The spontaneous Hall effect in a chiral superconductor is, however, nonuniversal. Our analysis is based on three approaches to the problem: a self-consistent solution of the Bogoliubov-de Gennes equation, a generalized Ginzburg-Landau theory, and a hydrodynamic formulation. All three methods consistently lead to the same conclusion that the spontaneous Hall resistance of a two-dimensional superconducting Hall bar is of order h/(ekFλ)2, where kF is the Fermi wave vector and λ is the London penetration depth; the Hall resistance is substantially suppressed from a quantum unit of resistance. Experimental issues in measuring this effect are briefly discussed.

  10. Hall current effects in dynamic magnetic reconnection solutions

    International Nuclear Information System (INIS)

    Craig, I.J.D.; Heerikhuisen, J.; Watson, P.G.

    2003-01-01

    The impact of Hall current contributions on flow driven planar magnetic merging solutions is discussed. The Hall current is important if the dimensionless Hall parameter (or normalized ion skin depth) satisfies c H >η, where η is the inverse Lundquist number for the plasma. A dynamic analysis of the problem shows, however, that the Hall current initially manifests itself, not by modifying the planar reconnection field, but by inducing a non-reconnecting perpendicular 'separator' component in the magnetic field. Only if the stronger condition c H 2 >η is satisfied can Hall currents be expected to affect the planar merging. These analytic predictions are then tested by performing a series of numerical experiments in periodic geometry, using the full system of planar magnetohydrodynamic (MHD) equations. The numerical results confirm that the nature of the merging changes dramatically when the Hall coupling satisfies c H 2 >η. In line with the analytic treatment of sheared reconnection, the coupling provided by the Hall term leads to the emergence of multiple current layers that can enhance the global Ohmic dissipation at the expense of the reconnection rate. However, the details of the dissipation depend critically on the symmetries of the simulation, and when the merging is 'head-on' (i.e., comprises fourfold symmetry) the reconnection rate can be enhanced

  11. Graphene and the universality of the quantum Hall effect

    DEFF Research Database (Denmark)

    Tzalenchuk, A.; Janssen, T. J.B.M.; Kazakova, O.

    2013-01-01

    The quantum Hall effect allows the standard for resistance to be defined in terms of the elementary charge and Planck's constant alone. The effect comprises the quantization of the Hall resistance in two-dimensional electron systems in rational fractions of RK=h/e2=25812.8074434(84) Ω (Mohr P. J....... the unconventional quantum Hall effect and then present in detail the route, which led to the most precise quantum Hall resistance universality test ever performed.......The quantum Hall effect allows the standard for resistance to be defined in terms of the elementary charge and Planck's constant alone. The effect comprises the quantization of the Hall resistance in two-dimensional electron systems in rational fractions of RK=h/e2=25812.8074434(84) Ω (Mohr P. J....... et al., Rev. Mod. Phys., 84 (2012) 1527), the resistance quantum. Despite 30 years of research into the quantum Hall effect, the level of precision necessary for metrology, a few parts per billion, has been achieved only in silicon and III-V heterostructure devices. In this lecture we show...

  12. Oceans Crossing: Factors Contributing to the Social and Academic Integration of Korean, Malaysian, and Taiwanese International Undergraduate Students at a Research University

    Science.gov (United States)

    Pham, Hoa

    2013-01-01

    The number of international students, especially Asian international students, studying at colleges and universities in the United States has increased dramatically during the past 50 years. As the fastest growing population on campus, Asian international students are also attracting more attention than ever before in higher education. However,…

  13. Signal conditioning and processing for metallic Hall sensors.

    Czech Academy of Sciences Publication Activity Database

    Entler, Slavomír; Ďuran, Ivan; Sládek, P.; Vayakis, G.; Kočan, M.

    2017-01-01

    Roč. 123, November (2017), s. 783-786 ISSN 0920-3796. [SOFT 2016: Symposium on Fusion Technology /29./. Prague, 05.09.2016-09.09.2016] R&D Projects: GA MŠk LG14002 Institutional support: RVO:61389021 Keywords : Hall sensor * Lock-in * Synchronous detection * Current spinning * Hall effect * Planar hall effect suppression Subject RIV: JF - Nuclear Energetics OBOR OECD: Nuclear related engineering Impact factor: 1.319, year: 2016 http://www.sciencedirect.com/science/article/pii/S0920379617305070

  14. Anomalous Hall effect in Fe/Gd bilayers

    KAUST Repository

    Xu, W. J.; Zhang, Bei; Liu, Z. X.; Wang, Z.; Li, W.; Wu, Z. B.; Yu, R. H.; Zhang, Xixiang

    2010-01-01

    Non-monotonic dependence of anomalous Hall resistivity on temperature and magnetization, including a sign change, was observed in Fe/Gd bilayers. To understand the intriguing observations, we fabricated the Fe/Gd bilayers and single layers of Fe and Gd simultaneously. The temperature and field dependences of longitudinal resistivity, Hall resistivity and magnetization in these films have also been carefully measured. The analysis of these data reveals that these intriguing features are due to the opposite signs of Hall resistivity/or spin polarization and different Curie temperatures of Fe and Gd single-layer films. Copyright (C) EPLA, 2010

  15. Hall conductance and topological invariant for open systems.

    Science.gov (United States)

    Shen, H Z; Wang, W; Yi, X X

    2014-09-24

    The Hall conductivity given by the Kubo formula is a linear response of quantum transverse transport to a weak electric field. It has been intensively studied for quantum systems without decoherence, but it is barely explored for systems subject to decoherence. In this paper, we develop a formulism to deal with this issue for topological insulators. The Hall conductance of a topological insulator coupled to an environment is derived, the derivation is based on a linear response theory developed for open systems in this paper. As an application, the Hall conductance of a two-band topological insulator and a two-dimensional lattice is presented and discussed.

  16. Acoustic investigations of concert halls for rock music

    DEFF Research Database (Denmark)

    Adelman-Larsen, Niels Werner; Thompson, Eric Robert; Gade, Anders Christian

    2007-01-01

    Objective measurement data and subjective evaluations have been collected from 20 small-/medium-sized halls in Denmark used for amplified rhythmic music concerts (pop, rock, jazz). The purpose of the study was to obtain knowledge about optimum acoustic conditions for this type of hall. The study...... is motivated by the fact that most concert tickets sold in Denmark relate to concerts within these genres in this kind of venue. The subjective evaluations were carried out by professional musicians and sound engineers who responded on the basis of their experiences working in these (and other) halls. From...

  17. Anomalous Hall effect in Fe/Gd bilayers

    KAUST Repository

    Xu, W. J.

    2010-04-01

    Non-monotonic dependence of anomalous Hall resistivity on temperature and magnetization, including a sign change, was observed in Fe/Gd bilayers. To understand the intriguing observations, we fabricated the Fe/Gd bilayers and single layers of Fe and Gd simultaneously. The temperature and field dependences of longitudinal resistivity, Hall resistivity and magnetization in these films have also been carefully measured. The analysis of these data reveals that these intriguing features are due to the opposite signs of Hall resistivity/or spin polarization and different Curie temperatures of Fe and Gd single-layer films. Copyright (C) EPLA, 2010

  18. All Optical Measurement Proposed for the Photovoltaic Hall Effect

    International Nuclear Information System (INIS)

    Oka, Takashi; Aoki, Hideo

    2011-01-01

    We propose an all optical way to measure the recently proposed p hotovoltaic Hall effect , i.e., a Hall effect induced by a circularly polarized light in the absence of static magnetic fields. This is done in a pump-probe experiment with the Faraday rotation angle being the probe. The Floquet extended Kubo formula for photo-induced optical response is formulated and the ac-Hall conductivity is calculated. We also point out the possibility of observing the effect in two layered graphene, three-dimensional graphite, and more generally in multi-band systems such as materials described by the dp-model.

  19. Determination of intrinsic spin Hall angle in Pt

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yi; Deorani, Praveen; Qiu, Xuepeng; Kwon, Jae Hyun; Yang, Hyunsoo, E-mail: eleyang@nus.edu.sg [Department of Electrical and Computer Engineering, National University of Singapore, 117576 (Singapore)

    2014-10-13

    The spin Hall angle in Pt is evaluated in Pt/NiFe bilayers by spin torque ferromagnetic resonance measurements and is found to increase with increasing the NiFe thickness. To extract the intrinsic spin Hall angle in Pt by estimating the total spin current injected into NiFe from Pt, the NiFe thickness dependent measurements are performed and the spin diffusion in the NiFe layer is taken into account. The intrinsic spin Hall angle of Pt is determined to be 0.068 at room temperature and is found to be almost constant in the temperature range of 13–300 K.

  20. Determination of intrinsic spin Hall angle in Pt

    International Nuclear Information System (INIS)

    Wang, Yi; Deorani, Praveen; Qiu, Xuepeng; Kwon, Jae Hyun; Yang, Hyunsoo

    2014-01-01

    The spin Hall angle in Pt is evaluated in Pt/NiFe bilayers by spin torque ferromagnetic resonance measurements and is found to increase with increasing the NiFe thickness. To extract the intrinsic spin Hall angle in Pt by estimating the total spin current injected into NiFe from Pt, the NiFe thickness dependent measurements are performed and the spin diffusion in the NiFe layer is taken into account. The intrinsic spin Hall angle of Pt is determined to be 0.068 at room temperature and is found to be almost constant in the temperature range of 13–300 K.

  1. Properties of Nonabelian Quantum Hall States

    Science.gov (United States)

    Simon, Steven H.

    2004-03-01

    The quantum statistics of particles refers to the behavior of a multiparticle wavefunction under adiabatic interchange of two identical particles. While a three dimensional world affords the possibilities of Bosons or Fermions, the two dimensional world has more exotic possibilities such as Fractional and Nonabelian statistics (J. Frölich, in ``Nonperturbative Quantum Field Theory", ed, G. t'Hooft. 1988). The latter is perhaps the most interesting where the wavefunction obeys a ``nonabelian'' representation of the braid group - meaning that braiding A around B then B around C is not the same as braiding B around C then A around B. This property enables one to think about using these exotic systems for robust topological quantum computation (M. Freedman, A. Kitaev, et al, Bull Am Math Soc 40, 31 (2003)). Surprisingly, it is thought that quasiparticles excitations with such nonabelian statistics may actually exist in certain quantum Hall states that have already been observed. The most likely such candidate is the quantum Hall ν=5/2 state(R. L. Willett et al, Phys. Rev. Lett. 59, 1776-1779 (1987)), thought to be a so-called Moore-Read Pfaffian state(G. Moore and N. Read, Nucl Phys. B360 362 (1991)), which can be thought of as a p-wave paired superconducting state of composite fermions(M. Greiter, X. G. Wen, and F. Wilczek, PRL 66, 3205 (1991)). Using this superconducting analogy, we use a Chern-Simons field theory approach to make a number of predictions as to what experimental signatures one should expect for this state if it really is this Moore-Read state(K. Foster, N. Bonesteel, and S. H. Simon, PRL 91 046804 (2003)). We will then discuss how the nonabelian statistics can be explored in detail using a quantum monte-carlo approach (Y. Tserkovnyak and S. H. Simon, PRL 90 106802 (2003)), (I. Finkler, Y. Tserkovnyak, and S. H. Simon, work in progress.) that allows one to explicitly drag one particle around another and observe the change in the wavefunctions

  2. State Legislators as Co-Pilots: Some "Helicopter Parents" Play Politics to Protect Their Children's Interests on Campuses

    Science.gov (United States)

    Lipka, Sara

    2005-01-01

    The US state lawmakers are concerned with the budgets and management of public colleges, though with a little push from "helicopter parents" who hover over their college-age children and challenge administrative decisions, legislators are increasingly intervening in a range of student-life issues. Frequently, legislators who are parents…

  3. An Empirical Test of an Expanded Version of the Theory of Planned Behavior in Predicting Recycling Behavior on Campus

    Science.gov (United States)

    Largo-Wight, Erin; Bian, Hui; Lange, Lori

    2012-01-01

    Background: The study and promotion of environmental health behaviors, such as recycling, is an emerging focus in public health. Purpose: This study was designed to examine the determinants of recycling intention on a college campus. Methods: Undergraduate students (N=189) completed a 35-item web-based survey past findings and an expanded version…

  4. Quantum Theory of Conducting Matter Superconductivity and Quantum Hall Effect

    CERN Document Server

    Fujita, Shigeji; Godoy, Salvador

    2009-01-01

    Explains major superconducting properties including zero resistance, Meissner effect, sharp phase change, flux quantization, excitation energy gap, and Josephson effects using quantum statistical mechanical calculations. This book covers the 2D superconductivity and the quantum Hall effects

  5. Magnesium Hall Thruster for Solar System Exploration, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation being developed in this program is a Mg Hall Effect Thruster system that would open the door for In-Situ Resource Utilization based solar system...

  6. W∞ gauge theory and the quantum Hall effect

    International Nuclear Information System (INIS)

    Shizuya, K.

    1994-05-01

    It is shown that a planar system of Hall electrons coupled to an applied electromagnetic field is written in the form of a W ∞ gauge theory. The associated W ∞ gauge field is expressed nonlinearly in terms of an infinite set of multipoles of the electromagnetic field. The W ∞ transformations generate mixing among the Landau levels. They provide a systematic way to classify the electromagnetic characteristics of the Hall system according to the resolution of external probes. In particular, an exact long-wavelength connection is derived between the carrier density and the Hall conductance in the presence of electron-electron interactions. Our approach is complementary to an earlier one and reveals a dual role the W ∞ gauge symmetry plays in the Hall dynamics. (author)

  7. Magnetohydrodynamic simulations of Gamble I POS with Hall effect

    International Nuclear Information System (INIS)

    Roderick, N.F.; Frese, M.H.; Peterkin, R.E.; Payne, S.S.

    1989-01-01

    Two dimensional single fluid magnetohydrodynamic simulations have been conducted to investigate the effects of the Hall electric field on magnetic field transport in plasma opening switches of the type used on Gamble I. The Hall terms were included in the magnetic field transport equation in the two dimensional simulation code MACH2 through the use of a generalized Ohm's law. Calculations show the Hall terms augment the field transport previously observed to occur through ion fluid motion and diffusion. For modest values of microturbulent collision frequency, board current channels were observed . Results also show the magnetic field transport to be affected by the cathode boundary conditions with the Hall terms included. In all cases center of mass motion was slight

  8. The Dream Comes True in the Golden Hall

    Institute of Scientific and Technical Information of China (English)

    JianZhong; ChenJianguo

    2004-01-01

    Nanjing Traditional Music Ensemble has long dreamed of performing in Vienna's Golden Hall.Now the dream has come true.the whole troupe felt so exciting that they did not even sleep well during the flight.

  9. Observation of the anomalous Hall effect in GaAs

    International Nuclear Information System (INIS)

    Miah, M Idrish

    2007-01-01

    Devices for the direct detection of the spin current, based on the anomalous Hall effect (AHE), are fabricated on n-type GaAs bulk semiconductor materials. The AHE is observed in the device when the photoinduced spin-polarized electrons are injected into it, and it is found that the effect depends on the applied electric field. The origin of the field-dependent observed Hall effect is discussed based on the D'yakonov-Perel' (DP) spin relaxation mechanism. The spin-dependent Hall effect is also found to be enhanced with increasing doping concentration. The present experimental results might have potential applications in semiconductor spintronic devices since the effect is closely related to the spin Hall effect

  10. Observation of the anomalous Hall effect in GaAs

    Energy Technology Data Exchange (ETDEWEB)

    Miah, M Idrish [Nanoscale Science and Technology Centre, School of Science, Griffith University, Nathan, Brisbane, QLD 4111 (Australia); Department of Physics, University of Chittagong, Chittagong, Chittagong - 4331 (Bangladesh)

    2007-03-21

    Devices for the direct detection of the spin current, based on the anomalous Hall effect (AHE), are fabricated on n-type GaAs bulk semiconductor materials. The AHE is observed in the device when the photoinduced spin-polarized electrons are injected into it, and it is found that the effect depends on the applied electric field. The origin of the field-dependent observed Hall effect is discussed based on the D'yakonov-Perel' (DP) spin relaxation mechanism. The spin-dependent Hall effect is also found to be enhanced with increasing doping concentration. The present experimental results might have potential applications in semiconductor spintronic devices since the effect is closely related to the spin Hall effect.

  11. Nobel Prize in physics 1985: Quantum Hall effect

    International Nuclear Information System (INIS)

    Herrmann, R.

    1986-01-01

    The conditions (like very strong magnetic fields, ultralow temperatures, and occurrence of a two-dimensional electron gas in microelectronic structures) for the measurement of the quantum Hall effect are explained. Two possible measuring methods are described. Measuring results for p-Si-MOSFET, GaAs/AlGaAs heterojuntions and grain boundaries in InSb crystals are reported. Differences between normal (integer) and fractional quantum Hall effect are discussed. One of the important consequences is that by means of the quantum Hall effect the value h/e 2 can be determined with very high accuracy. In 1985 Klaus von Klitzing was awarded the Nobel Prize for his work on the quantum Hall effect

  12. Quantum Computing With Quasiparticles of the Fractional Quantum Hall Effect

    National Research Council Canada - National Science Library

    Averin, Dmitri

    2001-01-01

    The focus of this project was the theoretical study of quantum computation based on controlled transfer of individual quasiparticles in systems of quantum antidots in the regime of the Fractional Quantum Hall Effect (FQHE...

  13. Quantum Hall Ferroelectrics and Nematics in Multivalley Systems

    Science.gov (United States)

    Sodemann, Inti; Zhu, Zheng; Fu, Liang

    2017-10-01

    We study broken symmetry states at integer Landau-level fillings in multivalley quantum Hall systems whose low-energy dispersions are anisotropic. When the Fermi surface of individual pockets lacks twofold rotational symmetry, like in bismuth (111) [Feldman et al. , Observation of a Nematic Quantum Hall Liquid on the Surface of Bismuth, Science 354, 316 (2016), 10.1126/science.aag1715] and in Sn1 -xPbxSe (001) [Dziawa et al., Topological Crystalline Insulator States in Pb1 -xSnxSe , Nat. Mater. 11, 1023 (2012), 10.1038/nmat3449] surfaces, interactions tend to drive the formation of quantum Hall ferroelectric states. We demonstrate that the dipole moment in these states has an intimate relation to the Fermi surface geometry of the parent metal. In quantum Hall nematic states, like those arising in AlAs quantum wells, we demonstrate the existence of unusually robust Skyrmion quasiparticles.

  14. Hall effects and related phenomena in disordered Rashba 2DEG

    International Nuclear Information System (INIS)

    Inoue, Jun-ichiro; Kato, Takashi; Bauer, Gerrit E W; Molenkamp, Laurens W

    2009-01-01

    We review our recent work on the spin and anomalous Hall effects and other related phenomena caused by the intrinsic spin–orbit interaction. We focus our attention on disorder effects on these transport properties by adopting a model of a two-dimensional electron gas with a Rashba-type spin–orbit interaction. A spin-polarized model is adopted to calculate the anomalous Hall effect and anisotropic magnetoresistance. It is shown that the spin Hall conductivity in the ballistic transport regime is cancelled by the so-called vertex corrections for the disorder scattering, and that the anomalous Hall conductivity and anisotropic magnetoresistance vanish unless the lifetime is spin dependent. We further present results on spin accumulation under an electric field

  15. Dual Mode Low Power Hall Thruster, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Sample and return missions desire and missions like Saturn Observer require a low power Hall thruster that can operate at high thrust to power as well as high...

  16. Suitable reverberation time for halls for rock and pop music

    DEFF Research Database (Denmark)

    Adelman-Larsen, Niels Werner; Thompson, Eric Robert; Gade, Anders Christian

    2010-01-01

    The existing body of literature regarding the acoustic design of concert halls has focused almost exclusively on classical music, although there are many more performances of popular music, including rock and pop. Objective measurements were made of the acoustics of 20 rock music venues in Denmark....... The best-rated halls in the study have reverberation times that are approximately frequency independent from 0.6 to 1.2 s for hall volumes from 1000 to 6000 m3. The worst rated halls in the study had significantly higher reverberation times in the 63 and 125 Hz bands. Since most audiences at rock concerts...... are standing, absorption coefficients were measured with a standing audience from 63 Hz to 4 kHz. These measurements showed that a standing audience absorbs about five times as much energy in mid-/high-frequency bands as in low-frequency bands....

  17. Analysis of Hall Probe Precise Positioning with Cylindrical Permanent Magnet

    International Nuclear Information System (INIS)

    Belicev, P.; Vorozhtsov, A.S.; Vorozhtsov, S.B.

    2007-01-01

    Precise positioning of a Hall probe for cyclotron magnetic field mapping, using cylindrical permanent magnets, was analyzed. The necessary permanent magnet parameters in order to achieve ±20 μm position precision, were determined. (author)

  18. High Input Voltage Hall Thruster Discharge Converter, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The overall scope of this Phase I/II effort is the development of a high efficiency 15kW (nominal) Hall thruster discharge converter. In Phase I, Busek Co. Inc. will...

  19. Pragmatic data fusion uncertainty concerns: Tribute to Dave L. Hall

    CSIR Research Space (South Africa)

    Blasch, E

    2016-07-01

    Full Text Available Over the course of Dave Hall's career, he highlighted various concerns associated with the implementation of data fusion methods. Many of the issues included the role of uncertainty in data fusion, practical implementation of sensor fusion systems...

  20. 2D Electrostatic Potential Solver for Hall Thruster Simulation

    National Research Council Canada - National Science Library

    Koo, Justin W

    2006-01-01

    ...) for Hall thruster simulation. It is based on a finite volume discretization of a current conservation equation where the electron current density is described by a Generalized Ohm's law description...

  1. Precision of single-engage micro Hall effect measurements

    DEFF Research Database (Denmark)

    Henrichsen, Henrik Hartmann; Hansen, Ole; Kjær, Daniel

    2014-01-01

    Recently a novel microscale Hall effect measurement technique has been developed to extract sheet resistance (RS), Hall sheet carrier density (NHS) and Hall mobility (μH) from collinear micro 4-point probe measurements in the vicinity of an insulating boundary [1]. The technique measures in less...... than a minute directly the local transport properties, which enables in-line production monitoring on scribe line test pads [2]. To increase measurement speed and reliability, a method in which 4-point measurements are performed using two different electrode pitches has been developed [3......]. In this study we calculate the measurement error on RS, NHS and μH resulting from electrode position errors, probe placement, sample size and Hall signal magnitude. We show the relationship between measurement precision and electrode pitch, which is important when down-scaling the micro 4-point probe to fit...

  2. The integer quantum hall effect revisited

    Energy Technology Data Exchange (ETDEWEB)

    Michalakis, Spyridon [Los Alamos National Laboratory; Hastings, Matthew [Q STATION, CALIFORNIA

    2009-01-01

    For T - L x L a finite subset of Z{sup 2}, let H{sub o} denote a Hamiltonian on T with periodic boundary conditions and finite range, finite strength intetactions and a unique ground state with a nonvanishing spectral gap. For S {element_of} T, let q{sub s} denote the charge at site s and assume that the total charge Q = {Sigma}{sub s {element_of} T} q{sub s} is conserved. Using the local charge operators q{sub s}, we introduce a boundary magnetic flux in the horizontal and vertical direction and allow the ground state to evolve quasiadiabatically around a square of size one magnetic flux, in flux space. At the end of the evolution we obtain a trivial Berry phase, which we compare, via a method reminiscent of Stokes Theorem. to the Berry phase obtained from an evolution around an exponentially small loop near the origin. As a result, we show, without any averaging assumption, that the Hall conductance is quantized in integer multiples of e{sup 2}/h up to exponentially small corrections of order e{sup -L/{zeta}}, where {zeta}, is a correlation length that depends only on the gap and the range and strength of the interactions.

  3. Brand new hall in the main building

    CERN Multimedia

    Corinne Pralavorio

    2014-01-01

    The renovation of the UNIQA and post office premises is getting under way, with their reopening scheduled for the spring.   The renovation of the large hall in the main building (Building 500) has finally reached the home straight. As of this week, building contractors will get to work on the last part – the offices of UNIQA and La Poste. In the last week of November, the two concessions moved their offices across Route Scherrer to the same part of Building 510 where UBS was temporarily housed during the bank’s refurbishment. Their services were therefore unavailable for one day. The renovation work will last until the spring, with the new offices expected to open in May 2015. Between now and then, the windows and insulation will be completely refitted, with a view to reducing heat loss considerably, and, above all, the premises will be modernised to improve customer reception and service. For example, UNIQA’s new premises will feature a confidential area, guarantee...

  4. Acoustics in Halls for Speech and Music

    Science.gov (United States)

    Gade, Anders C.

    This chapter deals specifically with concepts, tools, and architectural variables of importance when designing auditoria for speech and music. The focus will be on cultivating the useful components of the sound in the room rather than on avoiding noise from outside or from installations, which is dealt with in Chap. 11. The chapter starts by presenting the subjective aspects of the room acoustic experience according to consensus at the time of writing. Then follows a description of their objective counterparts, the objective room acoustic parameters, among which the classical reverberation time measure is only one of many, but still of fundamental value. After explanations on how these parameters can be measured and predicted during the design phase, the remainder of the chapter deals with how the acoustic properties can be controlled by the architectural design of auditoria. This is done by presenting the influence of individual design elements as well as brief descriptions of halls designed for specific purposes, such as drama, opera, and symphonic concerts. Finally, some important aspects of loudspeaker installations in auditoria are briefly touched upon.

  5. Hall MHD reconnection in cometary magnetotail

    International Nuclear Information System (INIS)

    Jovanovic, Dusan; Shukla, Padma Kant; Morfill, Gregor

    2005-01-01

    The fine structure of cometary tails (swirls, loops and blobs) is studied in the framework of resistive magnetic reconnection without a guide field in a dusty plasma. For a high-beta plasma (β ∼ 1) consisting of electrons, ions, and immobile dust grains, a two-fluid description is used to study electromagnetic perturbations with the frequency below Ωi, propagating at an arbitrary angle, and including the effects of Hall current. A zero-order current associated with the anti-parallel magnetic configuration may exist even in the limit of zero plasma temperature in a dusty plasma due to a symmetry breaking between electrons and ions by dust grains that yields an E-vector x B-vector current. In the perturbed state, a new linear electromagnetic mode is found in dusty plasma which is evanescent below the Rao cut-off frequency and has the characteristic wavelength comparable to the ion skin depth, which enables the reconnection at short spatial scales. The role of the dust is found to be twofold, yielding a new mode outside of the current sheet and altering the continuity conditions at its edge by an inhomogeneous Doppler shift associated with the E-vector x B-vector current

  6. Linear waves in a resistive plasma with Hall current

    International Nuclear Information System (INIS)

    Almaguer, J.A.

    1992-01-01

    Dispersion relations for the case of a magnetized plasma are determined taking into account the Hall current and a constant resistivity, η, in Ohm's law. It is found that the Hall effect is relevant only for parallel (to the equilibrium magnetic field) wave numbers in the case of uniform plasmas, giving place to a dispersive behavior. In particular, the cases of η→0 and small (nonzero) resistivity are discussed

  7. Hall effect in the two-dimensional Luttinger liquid

    International Nuclear Information System (INIS)

    Anderson, P.W.

    1991-01-01

    The temperature dependence of the Hall effect in the normal state is a commom theme of all the cuprate superconductors and has been one of the more puzzling observations on these puzzling materials. We describe a general scheme within the Luttinger liquid theory of these two-dimensional quantum fluids which corrrelates the anomalous Hall and resistivity observations on a wide variety of both pure and doped single crystals, especially the data in the accompanying Letter of Chien, Wang, and Ong

  8. Thermoelectric and Hall-effect studies in hydrogenerated nickel foils

    International Nuclear Information System (INIS)

    Rani, R.; Nigam, A.N.

    1978-01-01

    Thermo e.m.f. and Hall constant of hydrogenerated nickel foils have been measured. Termo e.m.f. shows a sign reversal which is not due to the change in sign of the charge carriers, as indicated by the Hall-effect measurements. To account for the sign reversal of thermo e.m.f., it is found necessary to take into account the surface states of chemisorbed hydrogen on nickel

  9. Fractional statistics and fractional quantized Hall effect. Revision

    International Nuclear Information System (INIS)

    Tao, R.; Wu, Y.S.

    1984-01-01

    We suggest that the origin of the odd denominator rule observed in the fractional quantized Hall effect (FQHE) may lie in fractional statistics which governs quasiparticles in FQHE. A theorem concerning statistics of clusters of quasiparticles implies that fractional statistics does not allow coexistence of a large number of quasiparticles at fillings with an even denominator. Thus no Hall plateau can be formed at these fillings, regardless of the presence of an energy gap. 15 references

  10. Hall probe for measuring high currents in superconducting coils

    International Nuclear Information System (INIS)

    Ferendeci, A.M.

    1986-01-01

    Constructional details of a compact Hall probe for measuring high currents in superconducting coils are given. The Hall probe is easy to assemble and can be inserted or removed from the system without breaking the superconducting loop. Upper current limit of the probe can be increased by using larger magnetic core material. Shielding becomes necessary if the probe holder is to be placed near large current dependent magnetic fields

  11. Low-Cost, High-Performance Hall Thruster Support System

    Science.gov (United States)

    Hesterman, Bryce

    2015-01-01

    Colorado Power Electronics (CPE) has built an innovative modular PPU for Hall thrusters, including discharge, magnet, heater and keeper supplies, and an interface module. This high-performance PPU offers resonant circuit topologies, magnetics design, modularity, and a stable and sustained operation during severe Hall effect thruster current oscillations. Laboratory testing has demonstrated discharge module efficiency of 96 percent, which is considerably higher than current state of the art.

  12. High-performance LED luminaire for sports hall

    Science.gov (United States)

    Lee, Xuan-Hao; Yang, Jin-Tsung; Chien, Wei-Ting; Chang, Jung-Hsuan; Lo, Yi-Chien; Lin, Che-Chu; Sun, Ching-Cherng

    2015-09-01

    In this paper, we present a luminaire design with anti-glare and energy-saving effects for sports hall. Compared with traditional lamps using in a badminton court, the average illuminance on the ground of the proposed LED luminaire is enhanced about 300%. Besides, the uniformity is obviously enhanced and improved. The switch-on speed of lighting in sports hall is greatly reduced from 5-10 minutes to 1 second. The simulation analysis and the corresponding experiment results are demonstrated.

  13. Guiding Math Students to Campus Services: An Impact Evaluation of the Beacon Program at South Texas College

    Science.gov (United States)

    Visher, Mary; Butcher, Kristin F.; Cerna, Oscar S.

    2011-01-01

    This research rigorously evaluates whether a low-cost intervention can improve students' performance in developmental math. The "Beacon Mentoring Program" was developed at South Texas College by professors, administrators, and staff at the college. Surveys of students revealed that many did not have someone on campus whom they felt they…

  14. Students' Emotions for Achievement and Technology Use in Synchronous Hybrid Graduate Programmes: A Control-Value Approach

    Science.gov (United States)

    Butz, Nikolaus T.; Stupnisky, Robert H.; Pekrun, Reinhard

    2015-01-01

    Synchronous hybrid delivery (simultaneously teaching on-campus and online students using web conferencing) is becoming more common; however, little is known about how students experience emotions in this learning environment. Based on Pekrun's (2006) control-value theory of emotions, the dual purpose of this study was first to compare synchronous…

  15. Driving Home: An Analysis of Obesity-Related Behaviors among U.S. College Students Living On and Off Campus

    Science.gov (United States)

    Garcia, Sophia E.

    2015-01-01

    The purpose of this study was to determine whether there are differences in weight status, aerobic and strength physical activity, sugar-sweetened beverage consumption, and perceived stress about having enough money to buy nutritious meals between United States college students who live on campus and college students who live off campus. A…

  16. Anisotropic intrinsic spin Hall effect in quantum wires

    International Nuclear Information System (INIS)

    Cummings, A W; Akis, R; Ferry, D K

    2011-01-01

    We use numerical simulations to investigate the spin Hall effect in quantum wires in the presence of both Rashba and Dresselhaus spin-orbit coupling. We find that the intrinsic spin Hall effect is highly anisotropic with respect to the orientation of the wire, and that the nature of this anisotropy depends strongly on the electron density and the relative strengths of the Rashba and Dresselhaus spin-orbit couplings. In particular, at low densities, when only one subband of the quantum wire is occupied, the spin Hall effect is strongest for electron momentum along the [1-bar 10] axis, which is the opposite of what is expected for the purely 2D case. In addition, when more than one subband is occupied, the strength and anisotropy of the spin Hall effect can vary greatly over relatively small changes in electron density, which makes it difficult to predict which wire orientation will maximize the strength of the spin Hall effect. These results help to illuminate the role of quantum confinement in spin-orbit-coupled systems, and can serve as a guide for future experimental work on the use of quantum wires for spin-Hall-based spintronic applications. (paper)

  17. The quantum Hall's effect: A quantum electrodynamic phenomenon

    International Nuclear Information System (INIS)

    Arbab, A. I.

    2012-01-01

    We have applied Maxwell's equations to study the physics of quantum Hall's effect. The electromagnetic properties of this system are obtained. The Hall's voltage, V H = 2πħ 2 n s /em, where n s is the electron number density, for a 2-dimensional system, and h = 2πħ is the Planck's constant, is found to coincide with the voltage drop across the quantum capacitor. Consideration of the cyclotronic motion of electrons is found to give rise to Hall's resistance. Ohmic resistances in the horizontal and vertical directions have been found to exist before equilibrium state is reached. At a fundamental level, the Hall's effect is found to be equivalent to a resonant LCR circuit with L H = 2π m/e 2 n s and C H = me 2 /2πħ 2 n s satisfying the resonance condition with resonant frequency equal to the inverse of the scattering (relaxation) time, τ s . The Hall's resistance is found to be R H = √L H /C H . The Hall's resistance may be connected with the impedance that the electron wave experiences when it propagates in the 2-dimensional gas. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  18. Signatures of lattice geometry in quantum and topological Hall effect

    International Nuclear Information System (INIS)

    Göbel, Börge; Mook, Alexander; Mertig, Ingrid; Henk, Jürgen

    2017-01-01

    The topological Hall effect (THE) of electrons in skyrmion crystals (SkXs) is strongly related to the quantum Hall effect (QHE) on lattices. This relation suggests to revisit the QHE because its Hall conductivity can be unconventionally quantized. It exhibits a jump and changes sign abruptly if the Fermi level crosses a van Hove singularity. In this Paper, we investigate the unconventional QHE features by discussing band structures, Hall conductivities, and topological edge states for square and triangular lattices; their origin are Chern numbers of bands in the SkX (THE) or of the corresponding Landau levels (QHE). Striking features in the energy dependence of the Hall conductivities are traced back to the band structure without magnetic field whose properties are dictated by the lattice geometry. Based on these findings, we derive an approximation that allows us to determine the energy dependence of the topological Hall conductivity on any two-dimensional lattice. The validity of this approximation is proven for the honeycomb lattice. We conclude that SkXs lend themselves for experiments to validate our findings for the THE and—indirectly—the QHE. (paper)

  19. Tunnelling anomalous and planar Hall effects (Conference Presentation)

    Science.gov (United States)

    Matos-Abiague, Alex; Scharf, Benedikt; Han, Jong E.; Hankiewicz, Ewelina M.; Zutic, Igor

    2016-10-01

    We theoretically show how the interplay between spin-orbit coupling (SOC) and magnetism can result in a finite tunneling Hall conductance, transverse to the applied bias. For two-dimensional tunnel junctions with a ferromagnetic lead and magnetization perpendicular to the current flow, the detected anomalous Hall voltage can be used to extract information not only about the spin polarization but also about the strength of the interfacial SOC. In contrast, a tunneling current across a ferromagnetic barrier on the surface of a three-dimensional topological insulator (TI) can induce a planar Hall response even when the magnetization is oriented along the current flow[1]. The tunneling nature of the states contributing to the planar Hall conductance can be switched from the ordinary to the Klein regimes by the electrostatic control of the barrier strength. This allows for an enhancement of the transverse response and a giant Hall angle, with the tunneling planar Hall conductance exceeding the longitudinal component. Despite the simplicity of a single ferromagnetic region, the TI/ferromagnet system exhibits a variety of functionalities. In addition to a spin-valve operation for magnetic sensing and storing information, positive, negative, and negative differential conductances can be tuned by properly adjusting the barrier potential and/or varying the magnetization direction. Such different resistive behaviors in the same system are attractive for potential applications in reconfigurable spintronic devices. [1] B. Scharf, A. Matos-Abiague, J. E. Han, E. M. Hankiewicz, and I. Zutic, arXiv:1601.01009 (2016).

  20. A holographic model for the fractional quantum Hall effect

    Energy Technology Data Exchange (ETDEWEB)

    Lippert, Matthew [Institute for Theoretical Physics, University of Amsterdam,Science Park 904, 1090GL Amsterdam (Netherlands); Meyer, René [Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo,Kashiwa, Chiba 277-8568 (Japan); Taliotis, Anastasios [Theoretische Natuurkunde, Vrije Universiteit Brussel andThe International Solvay Institutes,Pleinlaan 2, B-1050 Brussels (Belgium)

    2015-01-08

    Experimental data for fractional quantum Hall systems can to a large extent be explained by assuming the existence of a Γ{sub 0}(2) modular symmetry group commuting with the renormalization group flow and hence mapping different phases of two-dimensional electron gases into each other. Based on this insight, we construct a phenomenological holographic model which captures many features of the fractional quantum Hall effect. Using an SL(2,ℤ)-invariant Einstein-Maxwell-axio-dilaton theory capturing the important modular transformation properties of quantum Hall physics, we find dyonic diatonic black hole solutions which are gapped and have a Hall conductivity equal to the filling fraction, as expected for quantum Hall states. We also provide several technical results on the general behavior of the gauge field fluctuations around these dyonic dilatonic black hole solutions: we specify a sufficient criterion for IR normalizability of the fluctuations, demonstrate the preservation of the gap under the SL(2,ℤ) action, and prove that the singularity of the fluctuation problem in the presence of a magnetic field is an accessory singularity. We finish with a preliminary investigation of the possible IR scaling solutions of our model and some speculations on how they could be important for the observed universality of quantum Hall transitions.

  1. A holographic model for the fractional quantum Hall effect

    Science.gov (United States)

    Lippert, Matthew; Meyer, René; Taliotis, Anastasios

    2015-01-01

    Experimental data for fractional quantum Hall systems can to a large extent be explained by assuming the existence of a Γ0(2) modular symmetry group commuting with the renormalization group flow and hence mapping different phases of two-dimensional electron gases into each other. Based on this insight, we construct a phenomenological holographic model which captures many features of the fractional quantum Hall effect. Using an -invariant Einstein-Maxwell-axio-dilaton theory capturing the important modular transformation properties of quantum Hall physics, we find dyonic diatonic black hole solutions which are gapped and have a Hall conductivity equal to the filling fraction, as expected for quantum Hall states. We also provide several technical results on the general behavior of the gauge field fluctuations around these dyonic dilatonic black hole solutions: we specify a sufficient criterion for IR normalizability of the fluctuations, demonstrate the preservation of the gap under the action, and prove that the singularity of the fluctuation problem in the presence of a magnetic field is an accessory singularity. We finish with a preliminary investigation of the possible IR scaling solutions of our model and some speculations on how they could be important for the observed universality of quantum Hall transitions.

  2. BOOSTING STUDENT LIFE SATISFACTION AND ENGAGEMENT TO IMPROVE ONLINE STUDENT RETENTION

    DEFF Research Database (Denmark)

    Slavensky, Henning; Hansen, Hans Jørgen; Knudsen, Mikael Bergholz

    2017-01-01

    ’ decisions to drop out is their full-time job; having a full-time job while studying full time is very time-consuming. Another reason for the student dropout is a feeling of disconnection with their fellow students and the campus environment. Consequently, various strategies to motivate and retain...... to the students what is expected of them. In addition, we have seen a decrease in students with fulltime jobs who, thus, are able to join the teaching synchronously, engaging them much more directly. This, combined with a new strategy of forming mixed teams of online and on-campus students, has boosted...

  3. DISK FORMATION IN MAGNETIZED CLOUDS ENABLED BY THE HALL EFFECT

    International Nuclear Information System (INIS)

    Krasnopolsky, Ruben; Shang, Hsien; Li Zhiyun

    2011-01-01

    Stars form in dense cores of molecular clouds that are observed to be significantly magnetized. A dynamically important magnetic field presents a significant obstacle to the formation of protostellar disks. Recent studies have shown that magnetic braking is strong enough to suppress the formation of rotationally supported disks in the ideal MHD limit. Whether non-ideal MHD effects can enable disk formation remains unsettled. We carry out a first study on how disk formation in magnetic clouds is modified by the Hall effect, the least explored of the three non-ideal MHD effects in star formation (the other two being ambipolar diffusion and Ohmic dissipation). For illustrative purposes, we consider a simplified problem of a non-self-gravitating, magnetized envelope collapsing onto a central protostar of fixed mass. We find that the Hall effect can spin up the inner part of the collapsing flow to Keplerian speed, producing a rotationally supported disk. The disk is generated through a Hall-induced magnetic torque. Disk formation occurs even when the envelope is initially non-rotating, provided that the Hall coefficient is large enough. When the magnetic field orientation is flipped, the direction of disk rotation is reversed as well. The implication is that the Hall effect can in principle produce both regularly rotating and counter-rotating disks around protostars. The Hall coefficient expected in dense cores is about one order of magnitude smaller than that needed for efficient spin-up in these models. We conclude that the Hall effect is an important factor to consider in studying the angular momentum evolution of magnetized star formation in general and disk formation in particular.

  4. Problem Based Learning - Linking Students and Industry

    DEFF Research Database (Denmark)

    Fink, Flemming K.

    2006-01-01

    WG2_G4 Problem based learning – linking students and industry: a case study from Aalborg, Denmark Flemming K. Flink ELITE Aalborg University In Aalborg University, Denmark, all study programmes are organised around inter-disciplinary project work in groups. Up to 50% of the study work is problem-...... is essentially problem solving. The presentation looks into on campus POPBL and the Facilitated Work Based Learning (FBL) for continuing education. It also presents case examples of POPBL work....

  5. WWC Review of the Report "Interactive Online Learning on Campus: Testing MOOCs and Other Platforms in Hybrid Formats in the University System of Maryland." What Works Clearinghouse Single Study Review

    Science.gov (United States)

    What Works Clearinghouse, 2015

    2015-01-01

    In the 2014 study, "Interactive Online Learning on Campus: Testing MOOCs and Other Platforms in Hybrid Formats in the University System of Maryland," researchers examined the impact of using hybrid forms of interactive online learning in seven undergraduate courses across seven universities in Maryland. Hybrid forms of interactive online…

  6. Hamaoka Atomic Energy Hall, Chubu Electric Power Co. , Inc

    Energy Technology Data Exchange (ETDEWEB)

    Kawasaki, Y [Chubu Electric Power Co. Inc., Nagoya (Japan)

    1979-10-01

    Hamaoka Nuclear Power Station was constructed in the very large site of about 1.6 million m/sup 2/ surrounded by sand dunes and pine forests at the southern tip of Shizuoka Prefecture. Hamaoka Atomic Energy Hall was built on the right side of this power station. This hall had been planned as a part of the works commemorating the 20th anniversary of the founding of the company, and was opened in August, 1972. The building is of steel frame type, and has two floors of 1135 m/sup 2/ total area. The first floor comprises cinema room, power generation corner and open gallery, and the second floor comprises meeting room, native land corner and observation room. Moreover, there is observation platform on the roof. The purpose of the hall is coexistence and coprosperity with the regional residents, and 13 persons make explanations to visitors having reached to 1.9 million as of the end of June, 1979. It is incorporated in the sightseeing route centering around the Omaezaki lighthouse. The cinema hall accommodates 120 men, and the films concerning nuclear power generation and the construction of a nuclear power plant are shown. In the power generation corner, the explanation on nuclear power generation is made with models and panels. The third hall is being built now as energy corner, and it will be completed in autumn, 1979.

  7. Hamaoka Atomic Energy Hall, Chubu Electric Power Co., Inc

    International Nuclear Information System (INIS)

    Kawasaki, Yukio

    1979-01-01

    Hamaoka Nuclear Power Station was constructed in the very large site of about 1.6 million m 2 surrounded by sand dunes and pine forests at the southern tip of Shizuoka Prefecture. Hamaoka Atomic Energy Hall was built on the right side of this power station. This hall had been planned as a part of the works commemorating the 20th anniversary of the founding of the company, and was opened in August, 1972. The building is of steel frame type, and has two floors of 1135 m 2 total area. The first floor comprises cinema room, power generation corner and open gallery, and the second floor comprises meeting room, native land corner and observation room. Moreover, there is observation platform on the roof. The purpose of the hall is coexistence and coprosperity with the regional residents, and 13 persons make explanations to visitors having reached to 1.9 million as of the end of June, 1979. It is incorporated in the sightseeing route centering around the Omaezaki lighthouse. The cinema hall accommodates 120 men, and the films concerning nuclear power generation and the construction of a nuclear power plant are shown. In the power generation corner, the explanation on nuclear power generation is made with models and panels. The third hall is being built now as energy corner, and it will be completed in autumn, 1979. (Kako, I.)

  8. Higher (odd dimensional quantum Hall effect and extended dimensional hierarchy

    Directory of Open Access Journals (Sweden)

    Kazuki Hasebe

    2017-07-01

    Full Text Available We demonstrate dimensional ladder of higher dimensional quantum Hall effects by exploiting quantum Hall effects on arbitrary odd dimensional spheres. Non-relativistic and relativistic Landau models are analyzed on S2k−1 in the SO(2k−1 monopole background. The total sub-band degeneracy of the odd dimensional lowest Landau level is shown to be equal to the winding number from the base-manifold S2k−1 to the one-dimension higher SO(2k gauge group. Based on the chiral Hopf maps, we clarify the underlying quantum Nambu geometry for odd dimensional quantum Hall effect and the resulting quantum geometry is naturally embedded also in one-dimension higher quantum geometry. An origin of such dimensional ladder connecting even and odd dimensional quantum Hall effects is illuminated from a viewpoint of the spectral flow of Atiyah–Patodi–Singer index theorem in differential topology. We also present a BF topological field theory as an effective field theory in which membranes with different dimensions undergo non-trivial linking in odd dimensional space. Finally, an extended version of the dimensional hierarchy for higher dimensional quantum Hall liquids is proposed, and its relationship to quantum anomaly and D-brane physics is discussed.

  9. G. Stanley Hall, Child Study, and the American Public.

    Science.gov (United States)

    Young, Jacy L

    2016-01-01

    In the final decades of the 19th century psychologist Granville Stanley Hall was among the most prominent pedagogical experts in the nation. The author explores Hall's carefully crafted persona as an educational expert, and his engagements with the American public, from 1880 to 1900, arguably the height of his influence. Drawing from accounts of Hall's lecture circuit in the popular press, a map of his talks across the nation is constructed to assess the geographic scope of his influence. These talks to educators on the psychology underlying childhood and pedagogy, and his views and research on child life more generally, were regularly discussed in newspapers and popular periodicals. The venues in which Hall's ideas were disseminated, discussed, and in some cases, dismissed are described. His efforts to mobilize popular support for, and assistance with, his research endeavors in child study are also discussed. Such efforts were controversial both within the burgeoning field of psychology and among the public. Through his various involvements in pedagogy, and concerted efforts to engage with the American public, Hall helped establish psychology's relevance to parenting and educational practices.

  10. Seville City Hall Chapter Room ceiling decoration

    Directory of Open Access Journals (Sweden)

    Robador, M. D.

    2010-02-01

    Full Text Available The present article describes a chemical and physical study of the colour, chemical composition and mineral phases of the decorative materials in the Seville City Hall Chapter House ceiling. The findings showed that the inner most layer of material, calcite, was covered with white lead, in turn concealed under a layer of gilded bole. The ceiling underwent re-gilding, also over bole, due in all likelihood to wear on the original gold leaf. In the nineteenth century, the entire ceiling with the exception of the inscriptions was whitewashed with calcite and white lead. Silver was employed on King John I’s sword (coffer 27. Gold leaf was used to adorn the royal attributes: crowns, belts, sceptres, swords and rosary beads. The high reliefs were likewise gilded. The pigments identified on the ceiling adornments included azurite, malachite, vermilion and gas black. A lime and ground dolomite mortar was used throughout.

    El objetivo de este trabajo es el estudio de diferentes aspectos, como el color, la composición química y las fases mineralógicas presentes en los diferentes materiales que forman la ornamentación del techo de la Sala Capitular del Ayuntamiento de Sevilla, mediante métodos físicos y químicos. Nuestros resultados muestran que el dorado fue realizado sobre una capa de bol previamente depositada sobre una lámina de blanco de plomo que cubría un estrato de calcita. Posteriormente, y probablemente debido a alteraciones en el dorado original, el techo fue de nuevo dorado usando una técnica similar. En el siglo XIX, casi todo el techo, excepto las zonas con inscripciones, fue blanqueado usando una mezcla de calcita y blanco de plomo. Se empleó plata para cubrir la espada del rey Juan I (casetón 27. Finísimas láminas de oro se usaron para decorar los atributos reales: coronas, cinturones, cetros, espadas y rosarios. En diferentes partes de la decoración fueron detectados pigmentos como azurita, malaquita, bermellón y

  11. The Impact of Emotions on Student Achievement in Synchronous Hybrid Business and Public Administration Programs: A Longitudinal Test of Control-Value Theory

    Science.gov (United States)

    Butz, Nikolaus T.; Stupnisky, Robert H.; Pekrun, Reinhard; Jensen, Jason L.; Harsell, Dana M.

    2016-01-01

    Synchronous hybrid delivery (simultaneously teaching on-campus and online students using Web conferencing) is becoming more common in higher education. However, little is known about students' emotions in these environments. Although often overlooked, emotions are fundamental antecedents of success. This study longitudinally examined the role of…

  12. Trends in preference, programming and design of concert halls for symphonic music

    DEFF Research Database (Denmark)

    Gade, Anders Christian

    2008-01-01

    This paper discusses the evolution in taste regarding concert hall acoustics and how this can be reflected in the new halls being built today. The clients' and listener's preferences are not only based on listening in existing halls; but also on listening to reproduced music recorded with microph......This paper discusses the evolution in taste regarding concert hall acoustics and how this can be reflected in the new halls being built today. The clients' and listener's preferences are not only based on listening in existing halls; but also on listening to reproduced music recorded...

  13. A riot on campus: The effects of social identity complexity on emotions and reparative attitudes after ingroup-perpetrated violence.

    Science.gov (United States)

    Costabile, Kristi A; Austin, Adrienne B

    2018-01-01

    When a group commits a transgression, members who identify closely with the group often engage in defensive strategies in which they are less likely to experience guilt and shame in response to the transgression than are less identified group members. Subsequently, highly identified group members are often less willing to offer reparations to the injured parties. Because appropriate emotional responses and reparations are critical to community reconciliation, the present investigation examined whether social identity complexity-the degree to which individuals perceive their multiple social identities as interrelated-reduced these defensive responses. In the aftermath of a campus riot, emotional responses and reparative attitudes of undergraduate students were assessed. Results indicated that individuals who closely identified with the university were in fact capable of experiencing guilt and shame, but only if they also had complex social identities. A path model indicated that emotional responses, in turn, predicted willingness to provide reparations to the campus community. Accordingly, social identity complexity provides a new approach to understanding responses to ingroup-perpetrated violence. © 2017 Wiley Periodicals, Inc.

  14. Modular invariance, universality and crossover in the quantum Hall effect

    International Nuclear Information System (INIS)

    Dolan, Brian P.

    1999-01-01

    An analytic form for the conductivity tensor in crossover between two quantum Hall plateaux is derived, which appears to be in good agreement with existing experimental data. The derivation relies on an assumed symmetry between quantum Hall states, a generalisation of the law of corresponding states from rational filling factors to complex conductivity, which has a mathematical expression in terms of an action of the modular group on the upper-half complex conductivity plane. This symmetry implies universality in quantum Hall crossovers. The assumption that the β-function for the complex conductivity is a complex analytic function, together with some experimental constraints, results in an analytic expression for the crossover, as a function of the external magnetic field

  15. Carl Gustav Jung and Granville Stanley Hall on Religious Experience.

    Science.gov (United States)

    Kim, Chae Young

    2016-08-01

    Granville Stanley Hall (1844-1924) with William James (1842-1910) is the key founder of psychology of religion movement and the first American experimental or genetic psychologist, and Carl Gustav Jung (1875-1961) is the founder of the analytical psychology concerned sympathetically about the religious dimension rooted in the human subject. Their fundamental works are mutually connected. Among other things, both Hall and Jung were deeply interested in how the study of religious experience is indispensable for the depth understanding of human subject. Nevertheless, except for the slight indication, this common interest between them has not yet been examined in academic research paper. So this paper aims to articulate preliminary evidence of affinities focusing on the locus and its function of the inner deep psychic dimension as the religious in the work of Hall and Jung.

  16. Admittance of multiterminal quantum Hall conductors at kilohertz frequencies

    International Nuclear Information System (INIS)

    Hernández, C.; Consejo, C.; Chaubet, C.; Degiovanni, P.

    2014-01-01

    We present an experimental study of the low frequency admittance of quantum Hall conductors in the [100 Hz, 1 MHz] frequency range. We show that the frequency dependence of the admittance of the sample strongly depends on the topology of the contacts connections. Our experimental results are well explained within the Christen and Büttiker approach for finite frequency transport in quantum Hall edge channels taking into account the influence of the coaxial cables capacitance. In the Hall bar geometry, we demonstrate that there exists a configuration in which the cable capacitance does not influence the admittance measurement of the sample. In this case, we measure the electrochemical capacitance of the sample and observe its dependence on the filling factor

  17. Admittance of multiterminal quantum Hall conductors at kilohertz frequencies

    Energy Technology Data Exchange (ETDEWEB)

    Hernández, C. [Departamento de Física, Universidad Militar Nueva Granada, Carrera 11 101-80 Bogotá D.C. (Colombia); Consejo, C.; Chaubet, C., E-mail: christophe.chaubet@univ-montp2.fr [Université Montpellier 2, Laboratoire Charles Coulomb UMR5221, F-34095 Montpellier, France and CNRS, Laboratoire Charles Coulomb UMR5221, F-34095 Montpellier (France); Degiovanni, P. [Université de Lyon, Fédération de Physique Andrée Marie Ampère, CNRS, Laboratoire de Physique de l' Ecole Normale Supérieure de Lyon, 46 allée d' Italie, 69364 Lyon Cedex 07 (France)

    2014-03-28

    We present an experimental study of the low frequency admittance of quantum Hall conductors in the [100 Hz, 1 MHz] frequency range. We show that the frequency dependence of the admittance of the sample strongly depends on the topology of the contacts connections. Our experimental results are well explained within the Christen and Büttiker approach for finite frequency transport in quantum Hall edge channels taking into account the influence of the coaxial cables capacitance. In the Hall bar geometry, we demonstrate that there exists a configuration in which the cable capacitance does not influence the admittance measurement of the sample. In this case, we measure the electrochemical capacitance of the sample and observe its dependence on the filling factor.

  18. Crossover between spin swapping and Hall effect in disordered systems

    KAUST Repository

    Saidaoui, Hamed Ben Mohamed

    2015-07-16

    We theoretically study the crossover between spin Hall effect and spin swapping, a recently predicted phenomenon that consists of the interchange between the current flow and its spin polarization directions [M. B. Lifshits and M. I. Dyakonov, Phys. Rev. Lett. 103, 186601 (2009)]. Using a tight-binding model with spin-orbit coupled disorder, spin Hall effect, spin relaxation, and spin swapping are treated on equal footing. We demonstrate that spin swapping and spin Hall effect present very different dependencies as a function of the spin-orbit coupling and disorder strengths and confirm that the former exceeds the latter in the parameter range considered. Three setups are proposed for the experimental observation of the spin swapping effect.

  19. The quantum Hall effect in quantum dot systems

    International Nuclear Information System (INIS)

    Beltukov, Y M; Greshnov, A A

    2014-01-01

    It is proposed to use quantum dots in order to increase the temperatures suitable for observation of the integer quantum Hall effect. A simple estimation using Fock-Darwin spectrum of a quantum dot shows that good part of carriers localized in quantum dots generate the intervals of plateaus robust against elevated temperatures. Numerical calculations employing local trigonometric basis and highly efficient kernel polynomial method adopted for computing the Hall conductivity reveal that quantum dots may enhance peak temperature for the effect by an order of magnitude, possibly above 77 K. Requirements to potentials, quality and arrangement of the quantum dots essential for practical realization of such enhancement are indicated. Comparison of our theoretical results with the quantum Hall measurements in InAs quantum dot systems from two experimental groups is also given

  20. Diaphragm Effect of Steel Space Roof Systems in Hall Structures

    Directory of Open Access Journals (Sweden)

    Mehmet FENKLİ

    2015-09-01

    Full Text Available Hall structures have been used widely for different purposes. They have are reinforced concrete frames and shear wall with steel space roof systems. Earthquake response of hall structures is different from building type structures. One of the most critical nodes is diaphragm effect of steel space roof on earthquake response of hall structures. Diaphragm effect is depending on lateral stiffness capacity of steel space roof system. Lateral stiffness of steel space roof system is related to modulation geometry, support conditions, selected sections and system geometry. In current paper, three representative models which are commonly used in Turkey were taken in to account for investigation. Results of numerical tests were present comparatively