Reexamining Tenure at Hampshire College for the AAHE Section on "Reexamination of Tenure: Implications of Collective Bargaining and Contracts for Service."

Science.gov (United States)

Von Der Lippe, Robert

This paper, prepared for a panel discussion of tenure policies, describes newly established Hampshire College's adoption of a contract system, as opposed to a life-tenure system. Following the description is a consideration of possible alternatives within the contract system and of variations to tenure adopted by other campuses. At Hampshire,…

PENGARUH AUDIT TENURE TERHADAP FRAUDULENT FINANCIAL REPORTING DENGAN PENDEKATAN AKRUAL DISKRESIONER

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R. Nelly Nur apandi

2013-04-01

Full Text Available The purpose of this research was to describe audit tenure, fraudulent fianncial repoting, and the effect audit tenure on fraudulent fianncial reporting with discretionary accrual approach. This research used 83 samples of companies listed in Indonesia Stock Exchange period 2009-2010. Samples was collected by used puposive sample method. The hypothesis tested by simple linear regression analysis. The results of this study indicate that audit tenure for three consecutive years (2009-2011 there were 16 companies that have changed auditors every year, 36 companies that perform audit engagements with the same auditor for 2 years, and 31 companies that perform audit engagements with the same auditor for 3 years.While, the results of descriptive analysis showed that the fraudulent financial reporting has a minimum value is -0.7940, maximum values is 0.3670, and an average of fraudulent financial reporting at 83 companies listed in the Indonesia Stock Exchange is -0.010622. Financial reporting fraud rate indicates a value of less than zero (-0.010622, which indicates that there are indications of fraud in the form of earnings management with minimazation income, which lowers the level of income reported earnings. The results of hypothesis showed that the audit tenure has no effect on fraudulent financial reporting.

Tenure Issues in REDD+ Pilot Project Sites in Tanzania

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Therese Dokken

2014-02-01

Full Text Available REDD+ has been proposed as a viable option for addressing climate change in the near term, and at relatively low cost. There is a broad consensus that clearly defined tenure rights are important for the implementation and success of REDD+, both to manage forests effectively and to protect local communities’ livelihoods. We use primary data from 23 villages in six REDD+ pilot sites in Tanzania to identify causes of deforestation and forest degradation, and tenure rights issues, at the village level prior to project implementation. Further, interviews with project proponents and examination of project documents yields insights into how the proponents plan to address tenure issues. Most villages perceive their tenure as secure and have exclusion rights, while collective action challenges are prevalent in villages experiencing deforestation and forest degradation. These findings suggest that the main tenure issues are related to internal institutional arrangements. While we find that tenure is high on the agenda for all the project proponents, they are mainly focusing on formalization and securing tenure rights from state to community level. Though we do find this to be a precondition for reducing deforestation and degradation, some of their focus should be shifted to strengthening village institutions and enhancing internal compliance.

Tenured Teachers & Technology Integration in the Classroom

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Cox, Jerad

2013-01-01

This article explores teachers' technology integration in the classroom through 2 means: 1) what researchers are saying about emerging trends and best practices as well as, 2) the author's research assignment regarding the technology integration experiences of longer tenured teachers. More tenured teachers are different than their younger…

Land Tenure Insecurity and Inequality in Nicaragua

DEFF Research Database (Denmark)

Broegaard, Rikke

2005-01-01

This article uses empirical data from a case study in rural Nicaragua to demonstrate the need for a conceptualization of tenure security as seen from the perspective of the landholder. A large group of farmers in the case study area perceive their tenure situation as being insecure despite the fact...

Returns to Tenure, Firm-Specific Human Capital and Worker Heterogeneity

DEFF Research Database (Denmark)

Bingley, Paul; Westergård-Nielsen, Niels Chr.

2003-01-01

Workers with longer job tenure are paid more, on average, than those with shorter tenure. This paper re-opens the debate about whether individual financial returns to tenure are due to firm-specific human capital accumulation or sorting according to unobserved individual productivity heterogeneity...

Securing Land Tenure, Improving Food Security and Reducing ...

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

Securing Land Tenure, Improving Food Security and Reducing Poverty in Rural ... land tenure regimes as obstacles to food security, economic integration and ... its 2017 call for proposals to establish Cyber Policy Centres in the Global South.

Japan's Teachers Earn Tenure on Day One

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Ahn, Ruth; Asanuma, Shigeru; Mori, Hisayoshi

2016-01-01

Teachers in Japan earn tenure on their first day of employment--not after two years of experience based on evaluations of teaching performance or student test scores. This is almost too good to be true. If tenure is so easy to attain, how do the Japanese make sure their teachers, especially novice teachers hired with little teaching experience,…

Returns to Tenure, Firm-Specific Human Capital and Worker Heterogeneity

DEFF Research Database (Denmark)

Bingley, Paul; Westergård-Nielsen, Niels Chr.

2003-01-01

Workers with longer job tenure are paid more, on average, than those with shorter tenure. This paper re-opens the debate about whether individual financial returns to tenure are due to firm-specific human capital accumulation or sorting according to unobserved individual productivity heterogeneity...... firms to distinguish between firm-specific human capital and worker heterogeneity. Although the proportion of tenure returns due to firm-specific human capital is smaller than that found in the US, it has increased from 10% in 1980 to 30% in 1998 in Denmark. This change coincides with decentralisation...

Returns to Tenure or Seniority?

DEFF Research Database (Denmark)

Buhai, Ioan Sebastian; Portela, Miguel; Teulings, Coen

  This study documents two empirical regularities, using data for Denmark and Portugal. First, workers who are hired last, are the first to leave the firm (Last In, First Out; LIFO). Second, workers' wages rise with seniority (= a Worker's tenure relative to the tenure of her colleagues). We seek...... at the moment of separation). The LIFO rule provides a stronger bargaining position for senior workers, leading to a return to seniority in wages. Efficiency in hiring requires the workers' .bargaining power to be in line with their share in the cost of specific investment. Then, the LIFO rule is a way...

Job Tenure in Britain : Employee Characteristics Versus Workplace Effects

OpenAIRE

Mumford, Karen; Smith, Peter N.

2004-01-01

We consider differences in current job tenure of individuals using linked employee and workplace data. This enables us to distinguish between variation in tenure associated with the characteristics of individual employees and those of the workplace in which they work. The various individual characteristics are, as a group, found to be essentially uncorrelated with the workplace effect, however, this is not true for women and non-white employees. We find that the lower tenure associated with m...

THE METHODOLOGY USED TO INTERPRET CUSTOMARY LAND TENURE

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Gerrit Pienaar

2012-09-01

Full Text Available Customary land tenure is normally not based on codified or statutory sources, but stems from customary traditions and norms. When westernised courts have to interpret and adjudicate these customary traditions and norms, the normal rules of statutory interpretation cannot be followed. The court has to rely on evidence of the traditional values of land use to determine the rules connected to land tenure.Previously courts in many mixed jurisdictions relied on common or civil law legal principles to determine the nature of customary land tenure and lay down the principles to adjudicate customary land disputes among traditional communities, or between traditional and westernised communities in the same jurisdiction. Many examples of such westernised approach can be found in case law of Canada and South Africa. The interpretation of the nature of customary land tenure according to common law or civil law principles has been increasingly rejected by higher courts in South Africa and Canada, e.g. in Alexkor Ltd v The Richtersveld Community 2004 5 SA 469 (CC and Delgamuukw v British Columbia 1997 3 SCR 1010. This paper explores the methodology the courts should follow to determine what the distinctive nature of customary land tenure is. As customary land tenure is not codified or based on legislation, the court has to rely, in addition to the evidence of indigenous peoples, on the expert evidence of anthropologists and sociologists in determining the nature of aboriginal title (in Canada and indigenous land tenure (in South Africa. The court must approach the rules of evidence and interpret the evidence with a consciousness of the special nature of aboriginal claims and the evidentiary difficulties in proving a right which originates in times where there were no written records of the practices, customs and traditions engaged in. The court must not undervalue the evidence presented simply because that evidence does not conform precisely with the

Land Tenure, Gender, and Globalization : Research and Analysis ...

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

Land Tenure, Gender, and Globalization : Research and Analysis from Africa, Asia, and Latin America. Couverture du livre Land Tenure, Gender, and Globalization : Research and Analysis from Africa. Directeur(s) : Dzodzi Tsikata et Pamela Golah. Maison(s) d'édition : Zubaan, CRDI. 29 août 2009. ISBN : 9788189884727.

How Do Preservice Teachers View Tenure and Accountability?

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Thompson, Carol C.; Dentino, Gary

2016-01-01

Little research has examined preservice teachers' views on tenure and accountability. This study used a 35-item survey to investigate 89 preservice teachers' attitudes toward both. Most valued tenure and recognized the importance of ensuring teacher quality. Fewer than one third saw mentoring or collaboration as ways to improve their…

Being In-Between: Reflecting on Time, Space and Career during the Tenure Application Process

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Eichler, Mathew

2015-01-01

Part of the process of becoming a tenured faculty member is applying for tenure. This reflective essay reports on the period after the submission of tenure materials for review but before the review process for tenure is completed. This is an "in-between" space, where the race of the tenure track is no longer present, but the role of…

Land tenure in China: Legal, actual and perceived security

NARCIS (Netherlands)

Ma, Xianlei; Heerink, N.; Feng, S.; Shi, X.

2015-01-01

This paper examines the magnitudes of legal security, actual security and perceived security of farmland tenure, and the causes of currently prevailing land tenure insecurity in rural China. Two farm household surveys conducted in the northwest of Gansu province in 2010 and in the northeast of

Land tenure security and land investments in Northwest China

NARCIS (Netherlands)

Ma Xian lei, Xianlei; Heerink, N.; Ierland, van E.C.; Berg, van den M.; Shi, X.

2013-01-01

Purpose - The purpose of this paper is to examine the effect of perceived land tenure security in China on farmers' decisions to invest in relatively long-term land quality improvement measures, taking into account the potential endogeneity of tenure security. Design/methodology/approach – Data from

Socioeconomic Factors Influencing Customary Marine Tenure in the Indo-Pacific

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Joshua Cinner

2005-06-01

Full Text Available For generations communities in the Western Pacific have employed a range of resource management techniques (including periodic reef closures, gear restrictions, entry limitations, and the protection of spawning aggregations to limit marine resource use. Localized control over marine resources, commonly known as customary marine tenure (CMT, is the legal and cultural foundation for many of these practices. Because of their perceived potential to meet both conservation and community goals, these traditional resource management techniques are being revitalized by communities, governments, and NGOs as an integral part of national and regional marine conservation plans in the Pacific. However, the viability of conservation strategies built on a foundation of marine tenure may be in question, as it remains unclear whether marine tenure systems will be able to withstand the profound social and economic changes sweeping the Pacific region. Numerous studies have suggested that changes in marine tenure are attributed to social and economic factors, however, specific relationships between socioeconomic conditions and marine tenure are still not well understood. This paper examines the social and economic characteristics of 21 coastal communities in Papua New Guinea and Indonesia, and explores the characteristics of the communities that employ exclusive marine tenure to answer the following questions: Which socioeconomic factors are related to the presence of CMT regimes? How might socioeconomic factors influence the ability of communities to employ or maintain CMT regimes? Distance to market, immigration, dependence on fishing, and conflicts were found to be related to the presence of highly exclusive marine tenure systems. Exploring these relationships will help conservation practitioners better understand how future social changes may influence the foundation of conservation and development projects.

Tenure and Promotion Experiences of Academic Librarians of Color

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Damasco, Ione T.; Hodges, Dracine

2012-01-01

This study broadly examines factors impacting work-life experiences of library faculty of color within the framework of tenure policies and processes. An online survey was sent out to academic librarians of color to gauge perceptions of tenure and promotion policies and processes, professional activities and productivity, organizational climate…

Ministers of Health: short-term tenure for long-term goals?

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Ferraz, Marcos Bosi; Azevedo, Rafael Teixeira

2011-03-01

Healthcare investments should consider short and long-term demands. The objectives here were to compare the average tenures of ministers of health in Brazil and in another 22 countries and to evaluate the relationship between ministers' tenures and a number of indicators. Descriptive study conducted at Centro Paulista de Economia da Saúde (CPES). Twenty-two countries with the highest Human Development Indices (HDIs) and Brazil were included. The number of ministers over the past 20 years was investigated through each country's Ministry of Health website. Pearson's correlation coefficient was used to compare the number of ministers in each country with that country's indicators. The Mann-Whitney test was used to compare ministers' tenures in Brazil and other countries. The mean tenure (standard deviation, SD) of Brazilian ministers of health was 15 (12) months, a period that is statistically significantly shorter than the mean tenure of 33 (18) months in the other 22 countries (P < 0.05). There was a moderate and statistically significant positive correlation between the number of ministers and mortality rates for several conditions. The number of ministers also presented moderate and statistically significant negative correlations with per capita total healthcare expenditure (r = -0.567) and with per capita government healthcare expenditure (r = -0.530). On average, ministers of health have extremely short tenures. There is an urgent need to think and plan healthcare systems from a long-term perspective.

Optimal Policies for Random and Periodic Garbage Collections with Tenuring Threshold

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Zhao, Xufeng; Nakamura, Syouji; Nakagawa, Toshio

It is an important problem to determine the tenuring threshold to meet the pause time goal for a generational garbage collector. From such viewpoint, this paper proposes two stochastic models based on the working schemes of a generational garbage collector: One is random collection which occurs at a nonhomogeneous Poisson process and the other is periodic collection which occurs at periodic times. Since the cost suffered for minor collection increases, as the amount of surviving objects accumulates, tenuring minor collection should be made at some tenuring threshold. Using the techniques of cumulative processes and reliability theory, expected cost rates with tenuring threshold are obtained, and optimal policies which minimize them are discussed analytically and computed numerically.

Land tenure insecurity and rural-urban migration in rural China

NARCIS (Netherlands)

Ma Xian lei, Xianlei; Heerink, N.B.M.; Ierland, van E.C.; Shi Xiaoping, X.

2016-01-01

This paper examines the impact of land tenure security perceptions on rural-urban migration decisions of rural households, using data collected in Minle County in Northwest China. We find that tenure security perceptions play a significant role in household migration decisions in villages without

Does land tenure security matter for investment in soil and water conservation? Evidence from Kenya

NARCIS (Netherlands)

Kabubo-Mariara, J.; Linderhof, V.G.M.; Kruseman, G.

2010-01-01

This paper investigates the impact of tenure security and other factors on investment in soil and water conservation (SWC) in Kenya. Factor analysis, step-wise regression and reduced form model approaches are used to explain the willingness, likelihood and intensity of adoption of SWC investments.

Audit firm tenure and qualified opinions: New evidence from Spain

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Josep García Blandón

2013-06-01

Full Text Available The 2010 Green Paper on Audit Policy by the European Commission has explicitly questioned the sufficiency of audit rotation rules established by European Union Members to guarantee auditor independence. In addition, the Paper clearly states that more research is needed regarding the effects of long audit tenures on independence. In this article, we have replicated the research by Ruiz-Barbadillo, Gómez-Aguilar, and Biedma (2005 about the effects of audit firm tenure on independence with more updated data. However, unlike them, we have performed panel data estimations instead of pooled regression. Our approach allows for a better control of individual unobserved heterogeneity, thus reducing potential problems caused by omitted variable bias. While Ruiz-Barbadillo et al. reported an unexpected positive effect of tenure on the likelihood of audit qualifications, we do not show any significant effect of tenure on the opinion of the audit report. Our results are robust to various sensitivity analyses.

FACULTY DIVERSITY AND TENURE IN HIGHER EDUCATION.

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Abdul-Raheem, Jalelah

2016-01-01

There is a need for minority faculty in higher education due to the increase in minority high school graduates and higher education enrollees. Faculty members who are tenured have the ability to advocate for cultural equality in their institutions and serve as mentors for students. Minority faculty whose tenured process is hindered by inequality may also be unable to become a proper mentor for minority students. The purpose of this paper is to identify why faculty diversity will lead to increased student success and comfort, minority mentors, minority research, and equity advocacy, and representation from all minority groups.

A Review of Tenure for Black, Latino, and Native American Faculty in Academic Medicine.

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Fisher, Zedeena E; Rodríguez, José E; Campbell, Kendall M

2017-01-01

Tenure policies in US medical schools have been under scrutiny for decades while black/African American, Latino, and Native American faculty continue to be underrepresented in medicine. As medical institutions seek to improve diversity, tenure continues to be a major retention tool. We undertook a systematic review of the literature to investigate the role that tenure plays in the recruitment, retention, and advancement of underrepresented minorities in medicine (URMM) faculty in academic medicine. We searched PubMed, Google Scholar, Web of Knowledge, the Cumulative Index of Nursing and Allied Health Literature, and the Education Resources Information Center for articles relating to URMM faculty and tenure. Articles published in the last 20 years, in English, that discussed recruitment or retention of women, URMM faculty, and tenure in academic medicine, and were of high quality based on data were included in the study. Narrative reviews, opinion, editorials, and letters to the editor were excluded. Of the 1038 articles we reviewed, 23 met the criteria for inclusion. Tenure was associated with leadership, higher salaries, and comfort in the work environment. URMM faculty comprised the lowest percentage of tenured faculty in academic medicine, with the highest percentage pertaining to white men. More research needs to be done to determine whether tenure status can improve the number of URMM faculty in academic medicine. Tenure may provide URMM faculty the benefits that they need to progress in their careers and remain in academic medicine.

The Effects of Tenure and Task Orientation on Air Force Program Manager’s Role Stress

Science.gov (United States)

1976-06-16

Force Systems Command (AFSC) Manuals called the 虇 series’- that, in detail, pre- scribed the Air Force form of project management—program...related jobs. These jobs are con- ducive to low tenure policies because organizacional dis- ruption is minimal when individuals rotate. Other jobs

The effects of tenure and promotion on surgeon productivity.

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Lam, Adam; Heslin, Martin J; Tzeng, Ching-Wei D; Chen, Herbert

2018-07-01

Studies investigating the impact of promotion and tenure on surgeon productivity are lacking. The aim of this study is to elucidate the relationship of promotion and tenure to surgeon productivity. We reviewed data for the Department of Surgery at our institution. Relative value units (RVUs) billed per year, publications per year, and grant funding per year were used to assess productivity from 2010 to 2016. We analyzed tenure-track (TT) and non-tenure-track (NT) surgeons and compared the productivity within these groups by rank: assistant professor (ASST), associate professor (ASSOC), and full professor (FULL). Kruskal-Wallis and Mann-Whitney U tests were used to assess significance and relationships between the groups. A TT faculty was promoted if they produced more research, with the highest publication rates in TT FULL. TT faculty publishing rates increased from ASST to ASSOC (1 versus 2, P = 0.006) and from ASSOC to FULL (2 versus 4, P production (RVUs) was highest between TT ASSOC and NT FULL. TT faculty increased productivity between ASST and ASSOC (7023 versus 8384, P = 0.001) and decreased between ASSOC and FULL (8384 versus 6877, P production and grant funding, whereas NT FULL has the highest clinical production. Copyright © 2018 Elsevier Inc. All rights reserved.

Estimates for Future Tenure, Satisfaction and Biographical Variables as Predictors of Termination

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Waters, L. K.; And Others

1976-01-01

Findings of this study indicate that an employee's estimate of his/her future tenure with a company is a more reliable indication of actual tenure than job-satisfaction or biographical factors. (Author/RW)

Land tenure insecurity, vulnerability to climate-induced disaster and opportunities for redress in southern Africa

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Tigere Chagutah

2013-02-01

Full Text Available Land tenure is an important variable impacting on vulnerability to climate-related disaster. Land tenure insecurity is widespread in southern Africa and manifests itself in a number of ways that accentuate vulnerability to climate change impacts. Insecure tenure is seen to heighten vulnerability against growing demand for land for residential purposes and working space in urban areas while in the rural areas insecure tenure militates against diversified livelihoods and hinders investment in appropriate technologies and uptake of sound environmental management practices. Using the focused synthesis method, this article (1 maps the intersections between land tenure insecurity and vulnerability to climate-induced disaster in southern Africa; and (2 identifies the opportunities tenure reforms hold for vulnerability reduction in a region predicted to suffer widespread impacts from climate change. The paper contends that land tenure is a critical component of the milieu of factors – economic, social, cultural, institutional, political and even psychological – that are known to shape vulnerability and determine the environment that people live in. The study finds that land tenure reforms can help to reduce vulnerability and enhance community resilience to climate change. In this regard, the article outlines how tenure reforms can help build diverse household livelihoods, improve environmental management, particularly in the rural areas, and encourage investment in robust housing and safe neighbourhoods among the urban poor – all of which are integral to the region’s response to climate change.

The Land Act (1998) and Land Tenure Reform in Uganda | Okuku ...

African Journals Online (AJOL)

The Land Act (1998), which aims at reforming land tenure relations in Uganda, is therefore one of the most far-reaching legislation enacted by the National Resistance Movement (NRM) government. The new tenure system aims at supporting agricultural development through the functioning of a land market, establishing ...

Land Tenure as a Factor Underlying Agricultural Landscape Changes in Europe: A Review

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Krčílková Š.

2016-06-01

Full Text Available Land tenure is generally considered to be an important factor affecting farming, landscape, and rural development. This paper reviews selected case studies to identify how land tenure influences agricultural landscape changes in Europe. We identified how land tenure information was transformed into variables, grouping these variables into general thematic categories: (1 land rights variables based on references to the type of stakeholders and duration of land occupancy, (2 land structure variables describing general land structure, and (3 behavioural variables dependent on stakeholders’ attitudes, perceptions, and personal values. Each thematic category can be defined on three spatial levels: parcel or production block, stakeholder, and landscape. The results show that the tenure factor is not frequently included into landscape-change studies. When a land tenure factor was part of a given study, it either played a minor role among other drivers of landscape change or, if it influenced significant landscape changes, it had only locally specific effects. Moreover, there were studies with contradictory results and so it is difficult to generalize specific findings. Nevertheless, land tenure is frequently discussed within landscape-change research in relation to land abandonment as well as green services and their connection with the European Union’s Common Agricultural Policy.

Effect of land tenure and stakeholders attitudes on optimization of conservation practices in agricultural watersheds

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Piemonti, A. D.; Babbar-Sebens, M.; Luzar, E. J.

2012-12-01

Modeled watershed management plans have become valuable tools for evaluating the effectiveness and impacts of conservation practices on hydrologic processes in watersheds. In multi-objective optimization approaches, several studies have focused on maximizing physical, ecological, or economic benefits of practices in a specific location, without considering the relationship between social systems and social attitudes on the overall optimality of the practice at that location. For example, objectives that have been commonly used in spatial optimization of practices are economic costs, sediment loads, nutrient loads and pesticide loads. Though the benefits derived from these objectives are generally oriented towards community preferences, they do not represent attitudes of landowners who might operate their land differently than their neighbors (e.g. farm their own land or rent the land to someone else) and might have different social/personal drivers that motivate them to adopt the practices. In addition, a distribution of such landowners could exist in the watershed, leading to spatially varying preferences to practices. In this study we evaluated the effect of three different land tenure types on the spatial-optimization of conservation practices. To perform the optimization, we used a uniform distribution of land tenure type and a spatially varying distribution of land tenure type. Our results show that for a typical Midwestern agricultural watershed, the most optimal solutions (i.e. highest benefits for minimum economic costs) found were for a uniform distribution of landowners who operate their own land. When a different land-tenure was used for the watershed, the optimized alternatives did not change significantly for nitrates reduction benefits and sediment reduction benefits, but were attained at economic costs much higher than the costs of the landowner who farms her/his own land. For example, landowners who rent to cash-renters would have to spend ~120

Tenure and America's Community Colleges

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DiMaria, Frank

2012-01-01

America's colleges and universities have been moving slowly but steadily away from tenure over the past decade. The American Federation of Teachers reports that community colleges have seen a 22% increase in the number of instructional staff between 1997 and 2007. During that time, the percentage of community college faculty that were full-time…

Organization Tenure as a Moderator of the Job Satisfaction-Job Performance Relationship.

Science.gov (United States)

Norris, Dwight R.; Niebuhr, Robert E.

1984-01-01

Examined organization tenure as a moderator of the job satisfaction-job performance relationship with technical employees (N=116) in a medium-sized industrial firm. Results provided support for a moderating influence of organization tenure on the relationship between job performance and overall satisfaction, satisfaction with work, and…

Land tenure and the adoption of agricultural technology in Haiti:

OpenAIRE

Smucker, Glenn R.; White, T. Anderson; Bannister, Michael

2000-01-01

There has long been an active debate in Haiti - as in many other developing countries - over whether or not the customary tenure system constrains technology adoption and agricultural development, and whether cadaster and land titling should be national priorities. This paper contributes to this debate by reviewing and interpreting the body of literature and new empirical evidence concerning the relationship between land tenure and the adoption of technology in rural Haiti. The findings sugge...

Pre-tenured Faculty Job Satisfaction: An Examination of Personal Fit, Institutional Fit and Faculty Work-life

OpenAIRE

Awando, Maxwell Omondi

2014-01-01

The purpose of this study is to explore job satisfaction among pre-tenured faculty. More specifically I was interested in examining demographic and personal fit factors, fit with the norms and values of the institution among pre-tenured faculty in different institutional types. The sample for the study included all pre-tenured faculty members who completed the COACHE 2009- 2010 job satisfaction survey. The COACHE survey was administered to pre-tenured faculty at 149 four-year colleges and uni...

Strategies for Professors Who Service the University to Earn Tenure and Promotion

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Gentry, Ruben; Stokes, Dorothy

2015-01-01

Tenure and promotion are great aspirations for college professors. They are indicators of success in the professions. Universities stipulate in their official documents and numerous higher education publications specify what professors must achieve in order to earn tenure and promotion; which almost always cite effectiveness in teaching, research,…

Tenure and Promotion Experiences of Music Teacher Educators: A Mixed-Methods Study

Science.gov (United States)

Pellegrino, Kristen; Conway, Colleen M.; Millican, J. Si

2018-01-01

To examine music education faculty members' promotion and tenure experiences, we interviewed (N = 9) and surveyed (N = 124) music teacher educators (MTEs) who were pretenure or tenured within the past 3 years. Findings highlighted MTE's perceptions of evaluative criteria and standards, mentoring programs and experiences, professional identity, and…

Self-Esteem, Tenure, and Narcissistic Leader's Performance

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Hanna Peltokangas

2016-01-01

Full Text Available This study investigates the associations between the narcissistic leader and performance and the moderating effect of a leader’s tenure and self-esteem. The hypothesis were studied with Pearson correlations and stepwise hierarchical multiple regression analyses (n=203. The moderating effect of leader’s tenure on the relationship between narcissism and leader performance was confirmed. The narcissistic leader’s performance tends to be positively evaluated only because the leader has held the position for a very short period. Self-esteem exhibited a very strong correlation to leader performance. The results support the view that narcissism is a personality dimension, albeit one that is not necessarily pathological. The results of this study suggest it would be wise to add Rorschach Comprehensive System (RCS to the tools available in the personnel assessment situation.

Employee age and tenure within organizations: relationship to workplace satisfaction and workplace climate perceptions.

Science.gov (United States)

Teclaw, Robert; Osatuke, Katerine; Fishman, Jonathan; Moore, Scott C; Dyrenforth, Sue

2014-01-01

This study estimated the relative influence of age/generation and tenure on job satisfaction and workplace climate perceptions. Data from the 2004, 2008, and 2012 Veterans Health Administration All Employee Survey (sample sizes >100 000) were examined in general linear models, with demographic characteristics simultaneously included as independent variables. Ten dependent variables represented a broad range of employee attitudes. Age/generation and tenure effects were compared through partial η(2) (95% confidence interval), P value of F statistic, and overall model R(2). Demographic variables taken together were only weakly related to employee attitudes, accounting for less than 10% of the variance. Consistently across survey years, for all dependent variables, age and age-squared had very weak to no effects, whereas tenure and tenure-squared had meaningfully greater partial η(2) values. Except for 1 independent variable in 1 year, none of the partial η(2) confidence intervals for age and age-squared overlapped those of tenure and tenure-squared. Much has been made in the popular and professional press of the importance of generational differences in workplace attitudes. Empirical studies have been contradictory and therefore inconclusive. The findings reported here suggest that age/generational differences might not influence employee perceptions to the extent that human resource and management practitioners have been led to believe.

Audit tenure and financial reporting in Oman: Does rotation affect the quality

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Saeed Rabea Baatwah

2016-08-01

Full Text Available The purpose of this study is to provide an empirical result concerning the quality of audit under a rotation policy in the Gulf Cooperation Council (GCC. Currently, countries from GCC tend to require the audit firms of public companies to be rotated within four or five consecutive years. This policy received worldwide criticisms which asserted it deteriorates the quality of financial reports – instead of increasing their quality. To achieve this purpose, we use 573 observations from companies listed in the Omani capital market implementing audit firm rotation because Oman is the leading country in GCC. Using discretionary accruals and modified audit opinion to proxy financial reporting quality, we find that audit firm tenure is not significantly associated with low quality financial reports. We also found that audit partner tenure is not positively and significantly associated with high discretionary accruals while it is positively and significantly associated with modified audit opinion. We classify our audit tenure into short and long tenure and find similar findings. Additionally and contrary to previous findings in Oman, we report that audit committee characteristics such as independence, size, financial expertise and number of meetings are not associated with high quality financial reports. Thus, our study contains several contributions to audit tenure debates in general and corporate governance practices in GCC in particular

Evolving workplace flexibility for U.S. medical school tenure-track faculty.

Science.gov (United States)

Bunton, Sarah A; Corrice, April M

2011-04-01

The academic workplace has seen dramatic changes in recent decades, including growing faculty workloads, an increasingly demographically diverse faculty population, and changing expectations about workplace climate. Despite these significant changes, a typical medical faculty's career trajectory is often still quite linear and follows decades-old tenure policies. The authors describe the existence of flexible faculty policies related to tenure at U.S. medical schools to understand better the ways in which institutions are responding. Data primarily reflect responses from faculty affairs leaders at medical schools accredited by the Liaison Committee on Medical Education to a 2008 faculty personnel policies survey. These data are supplemented with results from the same survey fielded in previous years. The number of medical schools that have lengthened their probationary periods for faculty has increased over time, and, in 2008, nearly half of the institutions offered a probationary period length of eight years or more to faculty. Over three-fourths of the schools in 2008 had a tenure-clock-stopping policy available, and a third had a policy allowing faculty to work less than full-time while remaining on a tenure-eligible track. Findings suggest that many medical schools have made progress in making policy additions and modifications that acknowledge the changing academic workplace culture by adding flexibility to traditional tenure policies. Despite those efforts, significant opportunities remain for continued adoption of flexible policies so that faculty can achieve productive academic careers while balancing work, life, and family, and institutions can continue to recruit and retain high-quality faculty members. © by the Association of American Medical Colleges.

Academic Bullying: A Barrier to Tenure and Promotion for African-American Faculty

Science.gov (United States)

Frazier, Kimberly N.

2011-01-01

The author discusses the problem of retention of African American faculty due to tenure and promotion issues. The author outlines obstacles that African American face in the workplace while seeking tenure and promotion in academia. A case example is presented that illuminates how these stressors manifest in the academic setting and recommendations…

Tenure Security Reformand Electronic Registration: Exploring ...

African Journals Online (AJOL)

This paper examines the potential significance of updating registration practices in resolving some of the issues about tenure security in a transformative context. It deals with the importance of good governance in the context of land administration and considers its impact on intended reforms. Land registration practice as an ...

Personality as a Fourth Criterion for Tenure.

Science.gov (United States)

Zirkel, Perry A.

1985-01-01

A hypothetical case of denial of tenure by a public institution to a faculty member with persistent personality conflicts with colleagues is the context for a discussion of related legal issues and the results of previous court litigation. (MSE)

Pre-Tenured Faculty Job Satisfaction: An Examination of Personal Fit, Institutional Fit and Faculty Work-Life

Science.gov (United States)

Awando, Maxwell

2014-01-01

The purpose of this study is to explore job satisfaction among pre-tenured faculty. More specifically I was interested in examining demographic and personal fit factors, fit with the norms and values of the institution among pre-tenured faculty in different institutional types. The sample for the study included all pre-tenured faculty members who…

Forest tenure and sustainable forest management

Science.gov (United States)

J.P. Siry; K. McGinley; F.W. Cubbage; P. Bettinger

2015-01-01

We reviewed the principles and key literature related to forest tenure and sustainable forest management, and then examined the status of sustainable forestry and land ownership at the aggregate national level for major forested countries. The institutional design principles suggested by Ostrom are well accepted for applications to public, communal, and private lands....

Advancing Engaged Scholarship in Promotion and Tenure: A Roadmap and Call for Reform

Science.gov (United States)

O'Meara, KerryAnn; Eatman, Timothy; Petersen, Saul

2015-01-01

Despite the precipitous increase in nontenure-track faculty appointments, the promotion and tenure process continues to operate as a central "motivational and cultural force in the academic lives" of many faculty members. As a part of larger reward systems, the promotion and tenure process reflects institutional values, aspirations,…

Recognising land rights for conservation? tenure reforms in the Northern Sierra Madre, The Philippines

Directory of Open Access Journals (Sweden)

Jan van der Ploeg

2016-01-01

Full Text Available The legalisation of the customary land rights of rural communities is currently actively promoted as a strategy for conserving biodiversity. There is, however, little empirical information on the conservation outcomes of these tenure reforms. In this paper, we describe four conservation projects that specifically aimed to formalise land rights in the Philippines, a country widely seen as a model for the devolution of control over natural resources to rural communities. We demonstrate that these legalistic interventions are based on flawed assumptions, on: 1 the capacity of the state to enforce tenure; 2 the characteristics of customary land rights; and 3 the causal links between legal entitlements and sustainable natural resource management. As a result, these state-led tenure reforms actually aggravate tenure insecurity on the ground, and ultimately fail to improve natural resource management.

Land Tenure Induced Deforestation and Environmental Degradation ...

African Journals Online (AJOL)

Land Tenure Induced Deforestation and Environmental Degradation in Ethiopia: The Case of Arbagugu State Forest Development and Protection Project (A ... The objective of this paper is to explore the cause and impact of this overarching problem by focusing on Arbagugu State Forest Development and Protection Project, ...

Do social networks influence small-scale fishermen's enforcement of sea tenure?

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Kara Stevens

Full Text Available Resource systems with enforced rules and strong monitoring systems typically have more predictable resource abundance, which can confer economic and social benefits to local communities. Co-management regimes demonstrate better social and ecological outcomes, but require an active role by community members in management activities, such as monitoring and enforcement. Previous work has emphasized understanding what makes fishermen comply with rules. This research takes a different approach to understand what influences an individual to enforce rules, particularly sea tenure. We conducted interviews and used multiple regression and Akaike's Information Criteria model selection to evaluate the effect of social networks, food security, recent catch success, fisherman's age and personal gear investment on individual's enforcement of sea tenure. We found that fishermen's enforcement of sea tenure declined between the two time periods measured and that social networks, age, food security, and changes in gear investment explained enforcement behavior across three different communities on Nicaragua's Atlantic Coast, an area undergoing rapid globalization.

Professional Tenure: Is It Really a Solution?

Science.gov (United States)

Schaefer, C. Barry

1980-01-01

Dilemmas arising from a corporate lawyer's conflict between professional and organizational obligations are discussed, and the possible usefulness of attorney tenure is examined. It is concluded that strong and constructive management of the corporate legal function is preferable. Available from University of Nebraska, Lincoln, NE 68583; $3.75.…

Urban Middle School Instructional Special Education: Tenured versus Non-Tenured Teachers and the Impact on Academic Achievement

Science.gov (United States)

Wilson, Sheryl Marie

2010-01-01

The Iowa Test of Basic Skills (ITBS) is used in the Cahokia Unit School District No. 187 to give insight on student academic skill level in terms of years and months. Teacher strategies and expertise in the area of education are an integral part of the educational process. Tenure status, or the years of teaching experience, is plagued with the…

Significant Value Found in Mentoring Programs for Novice Tenure-Track Academic Librarians

OpenAIRE

Saori Wendy Herman, MLIS, AHIP

2016-01-01

A Review of: Goodsett, M., & Walsh, A. (2015). Building a strong foundation: Mentoring programs for novice tenure-track librarians in academic libraries. College & Research Libraries, 76(7), 914-933. http://dx.doi.org/10.5860/crl.76.7.914 Objective – To examine the effectiveness of mentoring programs for novice tenure-track academic librarians, and to identify critical elements that define a successful mentoring program in various academic library settings. Design – Survey questionn...

Legalising land rights. Local Practices, State Responses and Tenure Security in Africa, Asia and Latin America

OpenAIRE

Ubink, Janine M.; Hoekema, André J.; Assies, Willem J.

2009-01-01

Millions of people live and work on land that they do not legally own in accordance with enforceable state law. The absence of state recognition for local property rights affects people's tenure security and impedes development. Efforts to legalise extra-legal land tenure have traditionally emphasised individual titling and registration. Disappointment with such approaches have led to a search for 'a third way' in land tenure regulation that will reconcile state perspectives with local land r...

Excellence in teaching for promotion and tenure in animal and dairy sciences at doctoral/research universities: a faculty perspective.

Science.gov (United States)

Wattiaux, M A; Moore, J A; Rastani, R R; Crump, P M

2010-07-01

In this study, animal or dairy sciences faculty from doctoral/research universities were surveyed to clarify teaching performance expectations for the purpose of promotion and tenure of assistant professors. A survey tool including 15 evaluation criteria was available online and at the registration desk of the 2005 Joint Annual Meeting of the American Dairy Science Association and the American Society of Animal Science. The analyzed data set included 47 faculty (41 tenured and 6 tenure-track) with a substantial teaching responsibility from 27 different departments in 25 states. Four criteria were perceived as currently overemphasized: student evaluation of the instructor, student evaluation of the course, authoring peer-reviewed publications, and authoring an undergraduate textbook or book chapter. Nevertheless, more than 50% of respondents reported that these criteria should be used. One criterion emerged as being currently underemphasized: documentation of personal assessment of one's own teaching by preparing a portfolio. The lack of consensus for the remaining 10 items may have reflected substantial differences in institutional practices. The significance of overemphasis or underemphasis of certain criteria varied substantially depending on the respondent's perceived institutional mission. When asked about recognition within their department, 68% of respondents indicated that efforts in teaching improvement were properly rewarded. Respondents doubted the meaningfulness and appropriateness of student ratings tools as currently used. Results also suggested that animal and dairy science faculty placed a higher value on criteria recognizing excellence in teaching based on intradepartmental recognition (e.g., interactions with close-up peers and students) rather than recognition within a broader community of scholars as evidenced by authorship or success in generating funding for teaching. Proposed improvements in the evaluation of teaching for promotion and tenure

Debilitating lung disease among surface coal miners with no underground mining tenure.

Science.gov (United States)

Halldin, Cara N; Reed, William R; Joy, Gerald J; Colinet, Jay F; Rider, James P; Petsonk, Edward L; Abraham, Jerrold L; Wolfe, Anita L; Storey, Eileen; Laney, A Scott

2015-01-01

To characterize exposure histories and respiratory disease among surface coal miners identified with progressive massive fibrosis from a 2010 to 2011 pneumoconiosis survey. Job history, tenure, and radiograph interpretations were verified. Previous radiographs were reviewed when available. Telephone follow-up sought additional work and medical history information. Among eight miners who worked as drill operators or blasters for most of their tenure (median, 35.5 years), two reported poor dust control practices, working in visible dust clouds as recently as 2012. Chest radiographs progressed to progressive massive fibrosis in as few as 11 years. One miner's lung biopsy demonstrated fibrosis and interstitial accumulation of macrophages containing abundant silica, aluminum silicate, and titanium dust particles. Overexposure to respirable silica resulted in progressive massive fibrosis among current surface coal miners with no underground mining tenure. Inadequate dust control during drilling/blasting is likely an important etiologic factor.

Considering land tenure in REDD+ participatory measurement, reporting, and verification: A case study from Indonesia.

Directory of Open Access Journals (Sweden)

Mary Elizabeth Felker

Full Text Available Measurement, Reporting, and Verification (MRV systems are thought to be essential for effective carbon accounting and joint REDD+ carbon, conservation, and social development goals. Community participation in MRV (PMRV has been shown to be both cost effective and accurate, as well as a method to potentially advance stakeholder empowerment and perceptions of legitimacy. Recognizing land tenure as a long-standing point of tension in REDD+ planning, we argue that its engagement also has a key role to play in developing a legitimate PMRV. Using household surveys, key informant interviews, and participatory mapping exercises, we present three 'lived' land tenure contexts in Indonesia to highlight their socially and ecologically situated natures and to consider the role of tenure pluralism in shaping PMRV. We then raise and interrogate three questions for incorporating lived land tenure contexts into a legitimate PMRV system: 1 Who holds the right to conduct PMRV activities?; 2 How are the impacts of PMRV differentially distributed within local communities?; and 3 What is the relationship between tenure security and motivation to participate in PMRV? We conclude with implementation lessons for REDD+ practitioners, including the benefits of collaborative practices, and point to critical areas for further research.

State formation, religion, and land tenure in Cameroon

NARCIS (Netherlands)

Schilder, K.; African Studies Centre, Leiden

1988-01-01

The purpose of this analytical bibliography is to provide an overview of the recently published social science literature on State formation, religion, and land tenure in Cameroon. The 800 entries have been arranged under the following subject headings: The Cameroon State (nation building, political

Local politics of floodplain tenure in the Amazon

NARCIS (Netherlands)

de Castro, F.

2016-01-01

Research on community-based management system has been often grounded on monolithic institutional, social and ecological perspective with focus on the commoners as the only local actor, collective territorial rights as the only local tenure system, and the managed resource unit or ecosystem as the

Balancing Parenthood and Academia: Work/Family Stress as Influenced by Gender and Tenure Status

Science.gov (United States)

O'Laughlin, Elizabeth M.; Bischoff, Lisa G.

2005-01-01

The present research investigated the influence of gender and tenure status in academicians' experiences of balancing parenthood and an academic career. Men (n = 85) and women (n = 179) employed full-time in tenure-track academic positions with at least one child younger than the age of 16 responded via the Internet to a 36-item questionnaire…

Auditor tenure and auditor change: does mandatory auditor rotation improve audit quality?

OpenAIRE

M. Cameran; A. Prencipe; M. Trombetta

2009-01-01

We test the effects of auditor tenure and auditor change on audit quality in a unique mandatory audit firm rotation environment, where the rotation rule has been effective for more than 20 years. We first study the effect of audit tenure on audit quality. Our results show that audit quality—measured in terms of earnings management—tends to improve rather than worsen over time. We also examine the effects of voluntary auditor change vs. those resulting from mandatory auditor changes. Our resul...

Examining job tenure and lost-time claim rates in Ontario, Canada, over a 10-year period, 1999-2008.

Science.gov (United States)

Morassaei, Sara; Breslin, F Curtis; Shen, Min; Smith, Peter M

2013-03-01

We sought to examine the association between job tenure and lost-time claim rates over a 10-year period in Ontario, Canada. Data were obtained from workers' compensation records and labour force survey data from 1999 to 2008. Claim rates were calculated for gender, age, industry, occupation, year and job tenure group. A multivariate analysis and examination of effect modification were performed. Differences in injury event and source of injury were also examined by job tenure. Lost-time claim rates were significantly higher for workers with shorter job tenure, regardless of other factors. Claim rates for new workers differed by gender, age and industry, but remained relatively constant at an elevated rate over the observed time period. This study is the first to examine lost-time claim rates by job tenure over a time period during which overall claim rates generally declined. Claim rates did not show a convergence by job tenure. Findings highlight that new workers are still at elevated risk, and suggest the need for improved training, reducing exposures among new workers, promoting permanent employment, and monitoring work injury trends and risk factors.

Experience counts: The chief justice, management tenure, and strategic behavior on the U.S. Supreme Court

Directory of Open Access Journals (Sweden)

Joseph Daniel Ura

2016-04-01

Full Text Available We develop and test a theoretical account of the effect of management tenure on the strategic behavior of the chief justice of the United States. Substantial evidence from literatures on learning models and public management indicate that tenure (length of service is positively related to management performance in public organizations. This suggests that the chief justice’s tenure in office should be positively related to efficiency in the use of the chief justice’s formal powers. We assess this hypothesis by replicating and extending Johnson et al.’s study of chief justice Burger’s conference voting behavior. The data support our management tenure hypothesis, showing that Burger used greater discretion in reserving his conference vote over time as he became more adept at discriminating between circumstances when the tactic was strategically valuable and when it was not.

Tenure security, social relations and contract choice: Endogenous matching in the Chinese land rental market

Science.gov (United States)

Ma, Xianlei; Zhou, Yuepeng; Shi, Xiaoping

2017-04-01

In China, land rental transactions have increased considerably since the 1990s, but there exists a high degree of segmentation and informal features. The rental transactions between partners with close social relations and the use of informal contracts remain a common phenomenon in many regions, which strongly reduce the potential of the land rental market to enhance productivity and equity. The current literature postulates that the insecurity of land property rights may restrict land transactions between members of same social relations. Studies conducted in China show that the land rentals between partners with closer social relations prefer informal contracts because these contracts are self-enforced based on trust and reputation. However, little literature has jointly examined the effect of land tenure security and social relations on joint decisions of partner and contract choice in the Chinese land rental market. Based on household data collected in Jiangxi and Liaoning provinces in 2015, this paper aims to examine the relationship between land tenure security perceptions, social relation and land rental contract choices in China. We differentiate between formal and informal contracts of land rental activities because they have different enforcement mechanisms and thus different risk-sharing strategy. With regards to social relations, we differ among relatives, villagers living in the same village and strangers according to social distance. In order to reduce estimation bias without accounting for endogenous matching between landlords and tenants, we investigate the joint partner and contract choices in the land rental market using a nested logit framework. The paper contributes to the literature on the effect of tenure security and social relations on land rental contracts by (i) taking into account endogenous matching between landlords and tenants, and estimating the joint decisions of partner and contract choice, and (ii) examining the effect of perceived

Promoting the Inclusion of Tenure Earning Black Women in Academe: Lessons for Leaders in Education

Science.gov (United States)

Davis, Dannielle Joy; Reynolds, Rema; Jones, Tamara Bertrand

2011-01-01

This narrative work highlights one Black female faculty participant's experience of the Sisters of the Academy (SOTA) Research Boot Camp. She shares the benefits of the initiative, as well as how the program influenced her research and writing productivity as a faculty member. SOTA leadership supports Black female tenure-track and tenured faculty…

Awareness of Stress-Reduction Interventions on Work Attitudes: The Impact of Tenure and Staff Group in Australian Universities.

Science.gov (United States)

Pignata, Silvia; Winefield, Anthony H; Provis, Chris; Boyd, Carolyn M

2016-01-01

This study explored the impact of staff group role and length of organizational tenure in the relationship between the awareness of stress interventions (termed intervention awareness: IA) and the work-related attitudinal outcomes of university employees. A two-wave longitudinal study of a sample of 869 employees from 13 universities completed a psychosocial work factors and health questionnaire. Hierarchical regression analyses examined the contribution of staff role and different lengths of organizational tenure with IA and employees' reports of job satisfaction, affective organizational commitment, trust in senior management, and perceived procedural justice. Employees' length of tenure affected the relation between IA and work attitudes, and there were also differences between academic and non-academic staff groups. For non-academic employees, IA predicted job satisfaction, affective organizational commitment, trust in senior management, and perceived procedural justice. However, for academics, IA only predicted job satisfaction and trust which identifies a need to increase the visibility of organizational interventions. Across the tenure groups, IA predicted: (1) perceived procedural justice for employees with five or less years of tenure; (2) job satisfaction for employees with 0-19 years of tenure; (3) trust in senior management for employees with 6-19 years of tenure; and (4) affective organizational commitment for employees with a tenure length of 6-10 years. Employees working at the university for an intermediate period had the most positive perceptions of their organization in terms of IA, job satisfaction, trust in senior management, and affective organizational commitment, whereas employees with 20-38 years of tenure had the least positive perceptions. Results suggest that employees in the middle of their careers report the most positive perceptions of their university. The findings highlight the need to attend to contextual issues in organizational

Awareness of stress-reduction interventions on work attitudes: the impact of tenure and staff group in Australian universities

Directory of Open Access Journals (Sweden)

Silvia Pignata

2016-08-01

Full Text Available This study explored the impact of staff group role and length of organizational tenure in the relationship between the awareness of stress interventions (termed intervention awareness: IA and the work-related attitudinal outcomes of university employees. A two-wave longitudinal study of a sample of 869 employees from 13 universities completed a psychosocial work factors and health questionnaire. Hierarchical regression analyses examined the contribution of staff role and different lengths of organizational tenure with IA and employees’ reports of job satisfaction, affective organizational commitment, trust in senior management, and perceived procedural justice. Employees' length of tenure affected the relation between IA and work attitudes, and there were also differences between academic and non-academic staff groups. For non-academic employees, IA predicted job satisfaction, affective organizational commitment, trust in senior management, and perceived procedural justice. However, for academics, IA only predicted job satisfaction and trust which identifies a need to increase the visibility of organizational interventions. Across the tenure groups, IA predicted: (1 perceived procedural justice for employees with five or less years of tenure; (2 job satisfaction for employees with 0–19 years of tenure; (3 trust in senior management for employees with 6–19 years of tenure; and (4 affective organizational commitment for employees with a tenure length of 6–10 years. Employees working at the university for an intermediate period had the most positive perceptions of their organization in terms of IA, job satisfaction, trust in senior management, and affective organizational commitment, whereas employees with 20–38 years of tenure had the least positive perceptions. Results suggest that employees in the middle of their careers report the most positive perceptions of their university. The findings highlight the need to attend to contextual

Global Campaign to Eradicate Insecurity of Tenure by 2030

DEFF Research Database (Denmark)

McLaren, Robin; Enemark, Stig

2017-01-01

The global eradication of infectious diseases through highly coordinated campaigns has been successful. Although insecurity of tenure is not a disease, its impact is devastating in terms of trapping people in poverty, displacing communities and making them homeless, and reducing food security and...

The Methodology Used to Interpret Customary Land Tenure ...

African Journals Online (AJOL)

Many examples of such westernised approach can be found in case law of Canada and South Africa. The interpretation of the nature of customary land tenure according to common law or civil law principles has been increasingly rejected by higher courts in South Africa and Canada, e.g. in Alexkor Ltd v The Richtersveld ...

Book Review: Untitled: Securing Land Tenure in Urban and Rural ...

African Journals Online (AJOL)

Abstract. Book Title: Untitled: Securing Land Tenure in Urban and Rural South Africa. Book Authors: Hornby D, Kingwill R, Royston L & Cousins B (Eds.) (2017 University of KwaZulu-Natal Press) ISBN: 1869143507 ...

Predictors of job tenure in a lumber-plywood mill

Science.gov (United States)

Charles H. Wolf

1973-01-01

Multiple discriminant analysis was used to identify biographic and employment history variables associated with job tenure in a lumber-plywood mill. Several variables-friends and relatives, type of housing, commuting distance, and prior work experience in the wood industry-were found to be significant.

The tenure gap in electoral participation: Instrumental motivation or selection bias? Comparing homeowners and tenants across four housing regimes

OpenAIRE

André, S.C.H.; Dewilde, C.L.; Luijkx, R.

2017-01-01

Integrating housing tenure in Instrumental Motivation Theory predicts a tenure gap in electoral participation, as homeowners would be more motivated to vote compared with tenants. The empirical question is whether this effect is causal or rather due to selection into different housing tenures. This question is tackled using coarsened exact matching (CEM) on data for 19 countries, allowing us to better control for endogeneity. Even then, homeowners are found to vote more often than tenants. Th...

Optimal fossil-fuel taxation with backstop technologies and tenure risk

Energy Technology Data Exchange (ETDEWEB)

Strand, Jon [World Bank, Development Economics Group, Washington DC 20433 (United States); Department of Economics, University of Oslo (Norway)

2010-03-15

The paper derives the global welfare-optimizing time path for a tax on fossil fuels causing a negative stock externality (climate change), under increasing marginal extraction cost, and in the presence of an unlimited backstop resource causing no externality. In a basic competitive case, the optimal tax equals the Pigou rate, equivalent to the present discounted value of marginal damage costs. We consider two separate types of tenure insecurity for resource owners, and their impact on the tax implementing the optimal policy. When insecure control is with respect to future ownership to the resource, competitive extraction is higher than otherwise, and the efficiency-implementing tax exceeds the Pigou rate. When tenure insecurity instead implies possible expropriation ('holdup') of investment in extraction capacity, it deters extraction, and the optimal tax is lower than the Pigou rate. (author)

Changing the academic culture: valuing patents and commercialization toward tenure and career advancement.

Science.gov (United States)

Sanberg, Paul R; Gharib, Morteza; Harker, Patrick T; Kaler, Eric W; Marchase, Richard B; Sands, Timothy D; Arshadi, Nasser; Sarkar, Sudeep

2014-05-06

There is national and international recognition of the importance of innovation, technology transfer, and entrepreneurship for sustained economic revival. With the decline of industrial research laboratories in the United States, research universities are being asked to play a central role in our knowledge-centered economy by the technology transfer of their discoveries, innovations, and inventions. In response to this challenge, innovation ecologies at and around universities are starting to change. However, the change has been slow and limited. The authors believe this can be attributed partially to a lack of change in incentives for the central stakeholder, the faculty member. The authors have taken the position that universities should expand their criteria to treat patents, licensing, and commercialization activity by faculty as an important consideration for merit, tenure, and career advancement, along with publishing, teaching, and service. This position is placed in a historical context with a look at the history of tenure in the United States, patents, and licensing at universities, the current status of university tenure and career advancement processes, and models for the future.

Auditor Tenure and Stock Price Volatility: TheModerating Role of Auditor Industry Specialization

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Mehran Jorjani

2018-04-01

Full Text Available Purpose The present study aims to investigate the relationship between auditor tenure and stock return volatility and to study the moderating effect of auditor’s industry specialization on this relationship in the firms listed on the Tehran Stock Exchange (TSE. Design/methodology/approach A sample of 95 companies listed on the Tehran Stock Exchange during the period 2011 to 2015 was selected and two hypotheses were formulated and analyzed using multivariate regression and econometric models. Findings The results of the study indicate that with the increase of auditor tenure, the volatility of stock returns is reduced. However, the results showed that the use of auditors specializing in the client's industry does not affect the relationship between the length of auditor tenure and the volatility of stock returns. Originality/value The findings of current study not only extend the extant theoretical literature concerning the stock price volatility in developing countries including emerging capital market of Iran, but also help investors, capital market and audit profession regulators to make informed decisions.

Housing conditions of urban households with Aboriginal children in NSW Australia: tenure type matters.

Science.gov (United States)

Andersen, Melanie J; Williamson, Anna B; Fernando, Peter; Wright, Darryl; Redman, Sally

2017-08-01

Housing is a key determinant of the poor health of Aboriginal Australians. Most Aboriginal people live in cities and large towns, yet research into housing conditions has largely focused on those living in remote areas. This paper measures the prevalence of housing problems amongst participants in a study of urban Aboriginal families in New South Wales, Australia, and examines the relationship between tenure type and exposure to housing problems. Cross-sectional survey data was provided by 600 caregivers of 1406 Aboriginal children aged 0-17 years participating in Phase One of the Study of Environment on Aboriginal Resilience and Child Health (SEARCH). Regression modelling of the associations between tenure type (own/mortgage, private rental or social housing) and housing problems was conducted, adjusting for sociodemographic factors. The majority (60%) of SEARCH households lived in social housing, 21% rented privately and 19% either owned their home outright or were paying a mortgage ("owned"). Housing problems were common, particularly structural problems, damp and mildew, vermin, crowding and unaffordability. Physical dwelling problems were most prevalent for those living in social housing, who were more likely to report three or more physical dwelling problems than those in owned (PR 3.19, 95%CI 1.97, 5.73) or privately rented homes (PR 1.49, 1.11, 2.08). However, those in social housing were the least likely to report affordability problems. Those in private rental moved home most frequently; children in private rental were more than three times as likely to have lived in four or more homes since birth than those in owned homes (PR 3.19, 95%CI 1.97, 5.73). Those in social housing were almost half as likely as those in private rental to have lived in four or more homes since birth (PR 0.56, 95%CI 0.14, 0.77). Crowding did not vary significantly by tenure type. The high prevalence of housing problems amongst study participants suggests that urban Aboriginal

Legitimacy of forest rights: The underpinnings of the forest tenure reform in the protected areas of petén, Guatemala

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Iliana Monterroso

2012-01-01

Full Text Available In recent decades, forests across the world have undergone a significant process of recognition and transference of tenure rights to local communities or individuals, referred to here as forest tenure reforms. Among developing regions, Latin America has seen the most important recognition and transference of these tenure rights to forest dwelling and forest dependent communities. This paper examines the process in Guatemala, where the state has recognised and transferred rights to organised local groups-establishing a community concession system in the multiple use zone of the Maya Biosphere Reserve. We analyse the evolution of claims over forest uses, and focus on the legitimacy elements underpinning the process of a claim becoming a right. The results indicate that in order to sustain this forest tenure reform process over time, it is important to understand how tenure arrangements are transferred and distributed among rights-receivers, and how this process is influenced by the elements that underpin legitimation as well as those that define authority. Understanding the underpinnings of the legitimacy behind forest tenure reforms is central to identifying ways in which these processes can work, and also becomes important for developing more sound policy frameworks that fill gaps and resolve incongruence in governmental systems for forest management.

Pengaruh Struktur Corporate Governance, Audit Tenure Dan Ukuran Kantor Akuntan Publik (Kap) Terhadap Integritas Laporan Keuangan

OpenAIRE

Qoyyimah, Sofia Dinil; Kholmi, Masiyah; Harventy, Gina

2017-01-01

Purpose of this research to know influence of corporate governance, audit tenure, and KAP size tointegrity of financial statement. The method of analysis used is logistic regression analysis. Theresearch sample consisted of 14 state-owned companies listed in BEI 2011-2014.the results ofthe study show that the integrity of financial statements can not be controlled with corporategovernance, audit tenure and KAP size.

[Temporary employment and health: a multivariate analysis of occupational injury risk by job tenure].

Science.gov (United States)

Bena, Antonella; Giraudo, Massimiliano

2013-01-01

To study the relationship between job tenure and injury risk, controlling for individual factors and company characteristics. Analysis of incidence and injury risk by job tenure, controlling for gender, age, nationality, economic activity, firm size. Sample of 7% of Italian workers registered in the INPS (National Institute of Social Insurance) database. Private sector employees who worked as blue collars or apprentices. First-time occupational injuries, all occupational injuries, serious occupational injuries. Our findings show an increase in injury risk among those who start a new job and an inverse relationship between job tenure and injury risk. Multivariate analysis confirm these results. Recommendations for improving this situation include the adoption of organizational models that provide periods of mentoring from colleagues already in the company and the assignment to simple and not much hazardous tasks. The economic crisis may exacerbate this problem: it is important for Italy to improve the systems of monitoring relations between temporary employment and health.

Migrant workers in Italy: an analysis of injury risk taking into account occupational characteristics and job tenure

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Massimiliano Giraudo

2017-04-01

SMPC and Moroccan workers in the construction sector, while in the wholesale and retail trade sector an interaction effect of job tenure was only observed among Moroccan workers. Conclusions Migrant workers have higher occupational injury rates than Italians in the engineering and construction sectors, after two years of experience within the job. Generally the risk differentials vary depending on the nationality and economic sector considered. The analysis of injury risk among migrant workers should be restricted to serious injuries; furthermore, job tenure must be taken into account.

Migrant workers in Italy: an analysis of injury risk taking into account occupational characteristics and job tenure.

Science.gov (United States)

Giraudo, Massimiliano; Bena, Antonella; Costa, Giuseppe

2017-04-22

sector, while in the wholesale and retail trade sector an interaction effect of job tenure was only observed among Moroccan workers. Migrant workers have higher occupational injury rates than Italians in the engineering and construction sectors, after two years of experience within the job. Generally the risk differentials vary depending on the nationality and economic sector considered. The analysis of injury risk among migrant workers should be restricted to serious injuries; furthermore, job tenure must be taken into account.

The Effect of China’s New Circular Collective Forest Tenure Reform on Household Non-Timber Forest Product Production in Natural Forest Protection Project Regions

Directory of Open Access Journals (Sweden)

Yang Ren

2018-04-01

Full Text Available The implementation of China’s natural forest protection project (Protection Project in 1998 changed households’ forestry production modes in project regions, and China’s new circular collective forest tenure reform (Tenure Reform has been implemented since 2003 with the goal of motivating household forestry production and increasing household income from forests. Policymakers expect that Tenure Reform could also stimulate households to engage in non-timber forest products (NTFPs production in Protection Project regions. However, only a few studies have investigated the effect of Tenure Reform on household NTFP production in Protection Project regions. To fill this gap, we built an integrative conceptual framework and estimated a corresponding structural equation model (SEM using survey data from 932 households in Protection Project regions in southwestern China. In our research framework, there are four factors, including household characteristics, labour and social capital, forestland characteristics, and the Tenure Reform, affecting household NTFP production. The results substantiate that Tenure Reform has had a significant positive effect on household NTFP production. Additionally, household and forestland characteristics have promoted household NTFP production, but quantitatively less than Tenure Reform. This report can be used to inform the government that future investment in Tenure Reform still needs to be enhanced, and policy enforcement still needs to be strengthened.

Long Tenure and Punishment Effect on Corrupt Behaviour

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Winardi Rijadh Djatu

2017-01-01

Full Text Available This study implements behavioural economics and fraud auditing approach. This study looks at several factors that have been cited in previous studies as determinants of bribery. The result shows that long tenure increases the probability of corruption between civilian and public servant and penalty can be a good disincentive for corrupt behaviour but it is more effective towards the recipient instead of briber.

WWC Review of the Report "Are Tenure Track Professors Better Teachers?" What Works Clearinghouse Single Study Review

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What Works Clearinghouse, 2014

2014-01-01

The study reviewed here examined whether taking a course with a tenure track professor versus a non-tenure track professor for first-term freshman-level courses (e.g., introductory economics) had an impact on students' future enrollment and performance in classes in the same subject. Data from 15,662 students who entered Northwestern University,…

Historical Changes of Land Tenure and Land Use Rights in a Local Community: A Case Study in Lao PDR

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Saykham Boutthavong

2016-04-01

Full Text Available Land-titling programs, land and forest allocation programs, and projects on state-allocated land for development and investment in Laos have been key drivers of change in land tenure. These have triggered major shifts in land use rights, from customary, to temporary, and then to permanent land use rights. This article explores how government programs to grant land use rights to individual households have affected the way people have been able to acquire and secure land tenure. For our case study, we selected the village of Napo, the target of many land tenure changes in the past four decades. We collected data from district offices, group discussions with village organizations, and interviews with selected households. The study shows how land use rights shifted over time and reveals that households obtained most of their agricultural land and forestland through a claim process. Original households were mainly land claimers, while migrants were land buyers. The process of formalization and allocation of tenure triggered inequality among households. Attention is needed in future land governance and tenure reforms in order to safeguard the land use rights of local people in an equitable manner.

Effects of team tenure and leadership in self-managing teams

NARCIS (Netherlands)

Stoker, J.I.

2008-01-01

Purpose - This study seeks to identify the relationship between leader behaviour and the effectiveness of the members of a self-managing team (SMT) in terms of perceived individual performance and emotional exhaustion. In particular, it aims to examine the moderating role of individual team tenure.

Formal and informal land tenure systems in Afar region, Ethiopia ...

African Journals Online (AJOL)

commercial agriculture, land investments and development projects. Using data obtained ... tenure systems in Afar region, 2) to analyse the dynamics in land use and land administration from ..... According to the information obtained from the .... and land administration that take into account differences in economic, socio-.

Effects of land tenure, geology and topography on vegetation and ...

African Journals Online (AJOL)

This study compared the relative importance of land tenure, geology, slope angle and solar radiation index (calculated from aspect and slope angle) in influencing plant composition, basal cover, soil erosion and shrub encroachment in adjacent communal and commercial farming areas in two grassland types in South ...

effect of tenure security on livelihood activities of women farmers in ...

African Journals Online (AJOL)

KANETH

1989-05-03

May 3, 1989 ... Keywords: tenure security, livelihood activities and rural women. INTRODUCTION .... sale to buy farming inputs or other things they cannot produce. Also about 20% of the .... Internet Insiders, USA: McGraw Hill. Quan Julian ...

Case Study: A Peek behind the Curtain of Tenure and Promotion

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Herreid, Clyde Freeman; Prud'homme-Genereux, Annie; Schiller, Nancy A.; Herreid, Ky F.; Wright, Carolyn

2015-01-01

This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. This month's issue describes a survey that looks at the system for tenure and promotion.

Human Capital or Cultural Taxation: What Accounts for Differences in Tenure and Promotion of Racialized and Female Faculty?

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Wijesingha, Rochelle; Ramos, Howard

2017-01-01

Achieving tenure and promotion are significant milestones in the career of a university faculty member. However, research indicates that racialized and female faculty do not achieve tenure and promotion at the same rate as their non-racialized and male counterparts. Using new survey data on faculty in eight Canadian universities, this article…

Forming of Zr-4 alloy guide tube with varied diameters

International Nuclear Information System (INIS)

Wei Songyan; Tian Zhenye

1989-10-01

A new built-up mould method to manufacture Zr-4 alloy guide tubes with varied diameters at the middle of tube is introduced. The guide tube is used in nuclear power plants for guiding the control rods. This method has many advantages such as simple in forming, low cost of manufacturing, no need of special devices and favour of batch processing. The test results show that the accuracy of size, mechanical properties, resistance to corrosion, grain size and hydrogenate orientation of the end-products can meet the technical needs for nuclear reactor operation

Earnings Management through Goodwill Impairment: CEO and CFO tenure impact

NARCIS (Netherlands)

O.V. Visnevskaá (Olga)

2010-01-01

textabstractExecutive summary This paper examines the relationship between the extent of goodwill impairment and the properties of CEOs and CFOs of a selection of FTSE Eurotop 100 Index companies. Prior research indicated that it is likely that CEOs tend to take earnings baths early in their tenure,

Effects of land tenure, geology and topography on vegetation and ...

African Journals Online (AJOL)

A national degradation audit conducted in South Africa in the late 1990s found communal land tenure to be the strongest predictor of vegetation and soil degradation, while abiotic factors such as geology, slope and aspect were also correlated with degradation scores, but of secondary importance. This study compared the ...

Should God Get Tenure? Essays on Religion and Higher Education.

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Gill, David W., Ed.

Essays on the role of religion in higher education include: "Should God Get Tenure?" (David W. Gill); "On Being a Professor: The Case of Socrates" (Bruce R. Reichenbach); "Academic Excellence: Cliche or Humanizing Vision?" (Merold Westphal); "Religion, Science, and the Humanities in the Liberal Arts Curriculum" (H. Newton Maloney); "Tolstoy and…

The Glass Ceiling Is Made of Concrete: The Barriers to Promotion and Tenure of Women in American Academia

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Bonawitz, Mary; Andel, Nicole

2009-01-01

The focus of this research is to survey the literature in American higher education on the tenure and promotion of women and to suggest future problems that women may encounter as the American population grays. Anecdotally, women are not tenured and promoted in the same percentages of men in similar fields. In the social and natural sciences,…

Library School Programs and the Successful Training of Academic Librarians to Meet Promotion and Tenure Requirements in the Academy

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Best, Rickey D.; Kneip, Jason

2010-01-01

This article relates an investigation of tenure and promotion practices for librarians at academic institutions. The study employed two surveys. The first survey determined the level of impact on promotion and tenure by recent publication in two top-tier peer-reviewed journals: "College & Research Libraries" and "Journal of…

Leadership and organizational tenure diversity as determinants of project team effectiveness

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de Poel, Frouke M.; Stoker, Janka I.; Van der Zee, Karen I.

2014-01-01

The present study reveals how leadership effectiveness in project teams is dependent on the level of organizational tenure diversity. Data from 34 project teams showed that transformational leadership is related to organizational commitment, creative behavior, and job satisfaction, but only in teams

Leadership and Organizational Tenure Diversity as Determinants of Project Team Effectiveness

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de Poel, Frouke M.; Stoker, Janka I.; Van der Zee, Karen I.

2014-01-01

The present study reveals how leadership effectiveness in project teams is dependent on the level of organizational tenure diversity. Data from 34 project teams showed that transformational leadership is related to organizational commitment, creative behavior, and job satisfaction, but only in teams

Housing conditions of urban households with Aboriginal children in NSW Australia: tenure type matters

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Melanie J Andersen

2017-08-01

Full Text Available Abstract Background Housing is a key determinant of the poor health of Aboriginal Australians. Most Aboriginal people live in cities and large towns, yet research into housing conditions has largely focused on those living in remote areas. This paper measures the prevalence of housing problems amongst participants in a study of urban Aboriginal families in New South Wales, Australia, and examines the relationship between tenure type and exposure to housing problems. Methods Cross-sectional survey data was provided by 600 caregivers of 1406 Aboriginal children aged 0–17 years participating in Phase One of the Study of Environment on Aboriginal Resilience and Child Health (SEARCH. Regression modelling of the associations between tenure type (own/mortgage, private rental or social housing and housing problems was conducted, adjusting for sociodemographic factors. Results The majority (60% of SEARCH households lived in social housing, 21% rented privately and 19% either owned their home outright or were paying a mortgage (“owned”. Housing problems were common, particularly structural problems, damp and mildew, vermin, crowding and unaffordability. Physical dwelling problems were most prevalent for those living in social housing, who were more likely to report three or more physical dwelling problems than those in owned (PR 3.19, 95%CI 1.97, 5.73 or privately rented homes (PR 1.49, 1.11, 2.08. However, those in social housing were the least likely to report affordability problems. Those in private rental moved home most frequently; children in private rental were more than three times as likely to have lived in four or more homes since birth than those in owned homes (PR 3.19, 95%CI 1.97, 5.73. Those in social housing were almost half as likely as those in private rental to have lived in four or more homes since birth (PR 0.56, 95%CI 0.14, 0.77. Crowding did not vary significantly by tenure type. Conclusions The high prevalence of housing

Equality and Illusion: Gender and Tenure in Art History Careers

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Rudd, Elizabeth; Morrison, Emory; Sadrozinski, Renate; Nerad, Maresi; Cerny, Joseph

2008-01-01

Using a national survey of 508 art history Ph.D.s including data on graduate school performance and careers 10-15 years post-Ph.D., this study investigates gender, family, and academic tenure in art history, the humanities field with the highest proportion of women. Alternative hypotheses derived from three perspectives--termed here "clockwork,"…

Living with students: Lessons learned while pursuing tenure, administration, and raising a family.

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Humphrey, Michael; Callahan, Janet; Harrison, Geoff

2015-01-01

An emerging promising practice in many universities has been the development of faculty-in-residence programs, in which university faculty members and their family moved into university student residences, sharing common living spaces with students. This case study is centered on two faculty-in-residence living in university residence halls. One was an assistant professor pursuing tenure while raising a young child, while the second was a tenured full professor and associate dean raising two teens. This case study offers the post-experience conclusions of these two faculty-in-residence individuals, noting the benefits and challenges each experienced while living -and working closely with these students outside of the university classroom, all while striving for an optimal balance in managing professional and familial obligations.

N EX MIN TION OF TENURE SECURITY FOR URB N CROP F ...

African Journals Online (AJOL)

USER

2015-03-30

Mar 30, 2015 ... The study examined issues surrounding tenure security of land for urban crop farming and ... Data collected were .... and hybrid laws. ... providing vital food and income to a large ... (SAP) era, many of the companies and.

PENGARUH UKURAN KAP DAN AUDITOR TENURE TERHADAP VALUE RELEVANCE DARI NILAI WAJAR

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Taufik Hidayat

2012-12-01

Full Text Available This study examines the value relevance of fair value and whether the value relevance of fair value measured at quoted active market is higher than value measured at valuation techniques. We also examine whether the value relevance offair value with valuation techniques improves if auditor tenure is longer or financial statements are audited by a Big Four Firm. Hypothesis testing was conducted by a panel data based on model of Ohlson (1995. Using a sample of 147 companies listed on the Indonesia Stock Exchange from 2008-2011, resulting the general conclusion that fair value has value relevance, where the value relevance of fair value measured at quoted active market is higher than the valuation technique. Value relevance of fair value measured at valuation techniques will increase as auditor tenure increases or financial statements were audited by a Big Four Firm.

Effect of tenure security on livelihood activities of women farmers in ...

African Journals Online (AJOL)

On perceived effect of non-tenure security on livelihood activities, 17% percent of the respondents stated inability to use land for collateral, 25% complained about fragmentation of land, 23% complained about their inability of planting long duration crops, 20% complained about farming system being difficult to change, while ...

An Examination of Tenure Security for Urban Crop Farming in Lagos ...

African Journals Online (AJOL)

The study examined issues surrounding tenure security of land for urban crop farming and identified constraints that must be dealt with in order to facilitate land accessibility and productivity of urban crop farmers in the Lagos metropolis. 475 respondents of seven communities were selected through simple random sampling ...

How Tenure in Higher Education Relates to Faculty Productivity and Retention

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Manjounes, Cindy Kay

2016-01-01

Some public university systems are considering abolishing tenure as a cost-saving mechanism, but little is known about how this change may impact organizational outcomes related to faculty retention and research productivity. Using Almendarez' human capital theory, the purpose of this concurrent mixed methods study was to explore how tenure…

Staying Power: The Relationship of Public School Superintendent Tenure to Leadership Frames

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Elliff, Doyne Scott

2012-01-01

The study examined the types of leadership frames ("human resource," "structural," "political," and "symbolic") (Bolman & Deal, 1997) most often used by public school superintendents in Texas, the relationship of leadership frames to the length of superintendent tenure in a single school district, and…

Significant Value Found in Mentoring Programs for Novice Tenure-Track Academic Librarians

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Saori Wendy Herman, MLIS, AHIP

2016-12-01

Full Text Available A Review of: Goodsett, M., & Walsh, A. (2015. Building a strong foundation: Mentoring programs for novice tenure-track librarians in academic libraries. College & Research Libraries, 76(7, 914-933. http://dx.doi.org/10.5860/crl.76.7.914 Objective – To examine the effectiveness of mentoring programs for novice tenure-track academic librarians, and to identify critical elements that define a successful mentoring program in various academic library settings. Design – Survey questionnaire with a voluntary phone interview. Setting – Academic libraries in the United States of America. Subjects – 283 librarians participated in a survey questionnaire. Researchers conducted additional interviews with 6 out of the 12 librarians who had volunteered on the survey questionnaire and who met the inclusion criteria. Methods – Researchers recruited participants through two professional e-mail lists: the Information Literacy Instruction Discussion List (ILI-L listserv and the American Library Association’s New Members Round Table (NMRT listserv. Interested participants completed a secured online survey that was hosted using SurveyMonkey. The researchers then coded and analyzed the collected survey data using the same software. At the end of the online survey, participants were given the opportunity to volunteer for an additional interview. Potential interviewees were selected if mentoring programs were available for tenure- track librarians at their institutions. Once selected, researchers contacted potential interviewees and conducted interviews. The interviews were transcribed, the data anonymized, and original recordings deleted. Researchers coded the anonymized interview data to identify common themes.

Deficits, Declines, and Dismissals: Faculty Tenure and Fiscal Exigency. Current Issues.

Science.gov (United States)

Stroup, Stinson W.; And Others

Tenured faculty can be dismissed for reasons of financial exigency. If the employment contract provides a specific definition of fiscal exigency and the processes to be used in effecting retrenchment, then those terms govern in lieu of constitutional due process. In the absence of such guidance, courts are willing to allow dismissal for reasons of…

Proposal for refining business rules for petroleum and natural gas tenure in Alberta 1999 : attachment to Mineral Rights Information Bulletin 99-2

International Nuclear Information System (INIS)

1999-01-01

The position taken by Alberta Energy regarding petroleum and natural gas tenure is discussed. In September 1995, the Petroleum and Natural Gas Tenure Review Advisory Committee was established with representation from the Ministry of Energy and five industry associations. Since then, the Committee has published 10 proposals for industry review. The review resulted in the Mines and Minerals Amendment Act 1997, the Petroleum and Natural Gas Tenure Regulation, the Mines and Minerals Administration Regulation and the Crown Minerals Registration Regulation. The Alberta Department of Energy is committed to introducing further changes where necessary. Some of these changes are described in this proposal. They are: (1) changes to the mission of the the Department of Energy, (2) changes to the mission of the Mineral Operations Division, (3) changes to petroleum and natural gas tenure philosophies, (4) petroleum and natural gas licence administration, (5) petroleum and natural gas tenure regulations, (6) off-location wells, (7) continuations based on the Energy and Utilities Board's (EUB) approved projects, (8) changes to offset notices within the EUB approved projects, (9) serving notices on diagonally cornering spacing units, (10) offset compensation, (11) changes to applications where minister disagrees, (12) trespassing, and (13) water injection, water disposal, waster source and observation wells

Evaluating Faculty for Promotion and Tenure. The Jossey Bass Higher Education Series.

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Miller, Richard I.

Practical recommendations are offered for implementing an effective faculty evaluation system, based on the idea that quality promotion and tenure decisions are impossible without one. Weaknesses of current systems are described, including casual approaches and inadequate attention to decision making. Eight characteristics of effective systems are…

Community Tenure Rights and REDD+: A Review of the Oddar Meanchey Community Forestry REDD+ Project in Cambodia

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Donal Yeang

2012-01-01

Full Text Available Tenure rights over land, forest, and carbon have become a contentious issue within REDD+ implementation across the tropics because local communities could be excluded from REDD+ benefits if land tenure or use and access rights are not clear. This study aims to understand and assess tenure arrangements under the first REDD+ demonstration project in Cambodia, the Oddar Meanchey Com- munity Forestry REDD+ Project. In particular, the study explores the following questions: (1 How are tenure rights arranged in the Oddar Meanchey REDD+ Project? (2 Does the tenure regime recognise the rights of local communities to their land and its associated resources? (3 What kind of institu- tions are put in place to support tenure rights of local communities in the project? The author conducted in-depth semi-structured interviews with key stakeholders and complemented the analysis by participant observation and a review of policy documents and secondary literature. The major finding of this study is that the local communities in the project are still given rights to use and access forest resources, although carbon rights belong to the government. While the government retains ownership over carbon credits, it agreed that at least 50 percent of the net revenue from the sale of carbon credits will flow to participating communities. ------ Besitzrechte an Land, Wald und CO2 sind zu einer umkämpften Angelegenheit in der REDD+ Implementierung in den Tropen geworden. Diese Studie versucht die Besitzregelungen im ersten REDD+ Demons- trationsprojekt in Kambodscha, dem Oddar Meanchey Community Forestry REDD+ Project, zu verstehen und zu bewerten. Die Untersuchung analysiert dabei insbesondere folgende Fragen: (1 Wie sind Besitzrechte im Oddar Meanchey REDD+ Projekt geregelt? (2 Erkennt das Besitzsystem die Rechte von lokalen Gemeinschaften an ihrem Land und den dazugehörigen Ressourcen an? (3 Welche Institutionen werden geschaffen, um die Besitzrechte von lokalen

Factors Contributing to Job Satisfaction and Dissatisfaction among Non-Tenure-Track Faculty

Science.gov (United States)

Waltman, Jean; Bergom, Inger; Hollenshead, Carol; Miller, Jeanne; August, Louise

2012-01-01

While scholars have investigated the recent influx of non-tenure-track faculty (NTTF), few have talked extensively with NTTF to understand their perspectives. Using Herzberg's motivation-hygiene theory, we present focus group findings about job satisfaction of NTTF at 12 research universities. We highlight policies supporting teaching, job…

Thorny Tenure Case at Case Western Leads to Sex-Bias Charges: A Scientist with a Strong Publication Record Was Twice Denied Tenure, and Her Data Were Seized.

Science.gov (United States)

Smallwood, Scott

2001-01-01

Describes the case of a woman biology teacher who was denied tenure at Case Western Reserve University. Critics see her as a researcher who couldn't get along with students and who is blaming her problems on others. Supporters of the gender discrimination suit she is expected to file say that the Biology Department has a pattern of discrimination…

Are large farms more efficient? Tenure security, farm size and farm efficiency: evidence from northeast China

Science.gov (United States)

Zhou, Yuepeng; Ma, Xianlei; Shi, Xiaoping

2017-04-01

How to increase production efficiency, guarantee grain security, and increase farmers' income using the limited farmland is a great challenge that China is facing. Although theory predicts that secure property rights and moderate scale management of farmland can increase land productivity, reduce farm-related costs, and raise farmer's income, empirical studies on the size and magnitude of these effects are scarce. A number of studies have examined the impacts of land tenure or farm size on productivity or efficiency, respectively. There are also a few studies linking farm size, land tenure and efficiency together. However, to our best knowledge, there are no studies considering tenure security and farm efficiency together for different farm scales in China. In addition, there is little study analyzing the profit frontier. In this study, we particularly focus on the impacts of land tenure security and farm size on farm profit efficiency, using farm level data collected from 23 villages, 811 households in Liaoning in 2015. 7 different farm scales have been identified to further represent small farms, median farms, moderate-scale farms, and large farms. Technical efficiency is analyzed with stochastic frontier production function. The profit efficiency is regressed on a set of explanatory variables which includes farm size dummies, land tenure security indexes, and household characteristics. We found that: 1) The technical efficiency scores for production efficiency (average score = 0.998) indicate that it is already very close to the production frontier, and thus there is little room to improve production efficiency. However, there is larger space to raise profit efficiency (average score = 0.768) by investing more on farm size expansion, seed, hired labor, pesticide, and irrigation. 2) Farms between 50-80 mu are most efficient from the viewpoint of profit efficiency. The so-called moderate-scale farms (100-150 mu) according to the governmental guideline show no

The convergence of HIV/AIDS and customary tenure on women's access to land in rural Malawi.

Science.gov (United States)

Tschirhart, Naomi; Kabanga, Lucky; Nichols, Sue

2015-01-01

This paper examines the convergence of HIV/AIDS and the social processes through which women access customary land in rural Malawi. Data were collected from focus group discussions with women in patrilineal and matrilineal communities. Women's land tenure is primarily determined through kinship group membership, customary inheritance practices and location of residence. In patrilineal communities, land is inherited through the male lineage and women access land through relationships with male members who are the rightful heirs. Conversely in matrilineal matrilocal communities, women as daughters directly inherit the land. This research found that in patrilineal communities, HIV/AIDS, gendered inequalities embedded in customary inheritance practices and resource shortages combine to affect women's access to land. HIV/AIDS may cause the termination of a woman's relationship with the access individual due to stigma or the individual's death. Termination of such relationships increases tenure insecurity for women accessing land in a community where they do not have inheritance rights. In contrast to the patrilineal patrilocal experience, research on matrilineal matrilocal communities demonstrates that where women are the inheritors of the land and have robust land tenure rights, they are not at risk of losing their access to land due to HIV/AIDS.

Forging a Research Pathway: Perspectives of Two Post-Tenure Female Faculty Members

Science.gov (United States)

McIntyre, Laureen J.; Hellsten, Laurie-Ann M.

2014-01-01

This paper presents an auto-ethnographic exploration of two post-tenure female faculty member's experiences developing their programs of research. Self-reflection was used to explore the factors that have helped or hindered the development of their research program, and the continued challenges they faced as female faculty. Composite themes were…

DEVELOPMENT OF A PROJECT OF LAND TENURE IN THE STAVROPOL TERRITORY

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Elena Vyacheslavovna Pismennaya

2016-12-01

Full Text Available The provision of food security in Russia under conditions of the WTO and the Customs Union, the food import embargo and sanctions is a complex and multiscale task for supplying industry with the agricultural raw materials and the population with foodstuffs on stable basis and for achieving relative independence from the imports of raw materials and food products [1]. Currently, the agribusiness in the Stavropol Territory is developing faster than the agriculture in the neighboring regions of the North Caucasus Federal District. An analysis of the diversity of natural and socio-economic conditions in this Territory has shown that the existing areas of agricultural specialization do not correspond to the potential of the territory and the food security in general. With the reduction of the state financial support, an increase in the number of unprofitable farms has been marked. The structure of the foodstuff manufacturing (potatoes, fruits, milk, and meat is increasingly drawn to the small-scale farms. The consequence of the land and economic reforms becomes the imbalance structure of agricultural lands, livestock population, crop acreages and rotations, deterioration of soil fertility indices in large and medium agricultural enterprises. The low yielding natural forage grassland are prevailing. A biologically simplified system of farming has been formed, which leads to a short-term economic effect on the background of the phytosanitary and agrochemical sustainability drop of tillable lands and to the deterioration of the natural environment state. The production and yield of agricultural crops is increasingly dependent on weather conditions. This is unacceptable for the recovery of livestock production and effective arable farming [2]. In accordance with the implementation of the «Strategy of Socio-Economic Development of the North Caucasus Federal District until 2025», the Stavropol Territory in the future will continue focusing on the

Tips for Constructing a Promotion and Tenure Dossier that Documents Engaged Scholarship Endeavors

Science.gov (United States)

Franz, Nancy K.

2011-01-01

The growth of the community engagement movement in higher education over the past 2 decades has resulted in more faculty member interest and practice in engaged scholarship. As more institutions value this work, faculty members are looking for ways to enhance the effectiveness of their engaged scholarship dossiers for promotion and tenure. This…

Non-Tenure Track Faculty and Learning Communities: Bridging the Divide to Enhance Teaching Quality

Science.gov (United States)

Banasik, MaryJo D.; Dean, Jennifer L.

2016-01-01

Institutions of higher education are increasingly hiring non-tenure track faculty members (NTTF) to help meet the demands of the institutional teaching mission. Research suggests NTTF experience inadequate working conditions that hinder performance and negatively impact the quality of undergraduate education. Given the growing number of NTTF…

Promotion beyond Tenure: Unpacking Racism and Sexism in the Experiences of Black Womyn Professors

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Croom, Natasha N.

2017-01-01

This study examined seven Black womyn full professors' experiences of promotion beyond tenure. Using a critical race feminist theoretical framework, findings suggest that a meritocratic ideology undergirds a dominant narrative about the Professor rank. However, racism and sexism mediated the participants' opportunities to access the status and…

Land use and land tenure in Mongolia: A brief history and current issues

Science.gov (United States)

Maria E. Fernandez-Gimenez

2006-01-01

This essay argues that an awareness of the historical relationships among land use, land tenure, and the political economy of Mongolia is essential to understanding current pastoral land use patterns and policies in Mongolia. Although pastoral land use patterns have altered over time in response to the changing political economy, mobility and flexibility remain...

Union Security Provisions, Academic Freedom and Tenure: The Implications of Chicago Teachers Union v. Hudson.

Science.gov (United States)

Olswang, Steven G.

1988-01-01

The relationship between faculty union mandatory membership provisions in a collective bargaining agreement and the rights of faculty protected by tenure and academic freedom are examined, and college options and considerations in negotiating contracts under collective bargaining laws are discussed. (MSE)

The influence of quality of work life on employee job satisfaction, job commitment and tenure intention in the small and medium enterprise sectors

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Richard Chinomona

2014-08-01

Full Text Available A major reason for advocating for quality of work life has been the promise that it creates a win-win situation: improved employee satisfaction and welfare, hence increased productivity, longer employee tenure and consequently increased company profitability. Nevertheless, in the context of small to medium enterprises (SMEs, scant attention has been given to the empirical investigation into the influence of the quality of work life on employee tenure intention in Southern Africa. The purpose of this study is to fill this gap by examining the influence of SME employees’ perceptions of the quality of work life on their tenure intention and the mediating role of job satisfaction and job commitment in this relationship as far as Zimbabwe is concerned. Five hypotheses were posited and sample data of 282 were collected from Harare, Zimbabwe’s biggest city, to empirically test these hypotheses. The results of this study showed that, in the SME context, quality of work life positively and significantly influences employee job satisfaction, job commitment and consequently tenure intention. The managerial implications of the findings are discussed and limitations and future research directions are indicated.

Making Meaning of Experience: Navigating the Transformation from Graduate Student to Tenure-Track Professor

Science.gov (United States)

Coke, Pamela K.; Benson, Sheila; Hayes, Monie

2015-01-01

This article is about three adult authors who are making meaning of their experiences as early career, tenure-track professors. All former secondary English language arts instructors who are responsible for preparing future secondary English teachers, the authors use Mezirow's transformative learning theory lens to examine their trajectories from…

The Hidden Professoriate. Credentialism, Professionalism, and the Tenure Crisis. Contributions in Sociology, Number 29.

Science.gov (United States)

Wilke, Arthur S., Ed.

The paradoxical state of academe's attempt to crowd individuals into institutions of higher education at a time when jobs for them are evaporating has created a conflict within the academic personnel community for non-tenured faculty struggling to survive. Case studies representing actual experiences of some individuals directly involved in the…

Domestic and Foreign Consequences of China's Land Tenure Reform on Collective Forests

Science.gov (United States)

H. Zhang; Joseph Buongiorno; Shu-shuai Zhu

2012-01-01

Some of the long-term consequences of China’s collective forests tenure reform were projected with the Global Forest Products Model (GFPM). The reform had a positive effect on the wood supply and demand balance. By 2020 the reform led to a 14 to 36 percent decrease of China’s imports of industrial roundwood. Concurrently, the rest of the world produced less, but...

Enhancing marketing recruitment strategies: administrator tenure and nursing expenditures.

Science.gov (United States)

Gunby, Norris White

2005-01-01

When recruiting nurses, long-term care facilities require an ability to identify salient organizational characteristics that are attractive to potential nursing services candidates vis-à-vis their competitors. The findings of this study suggest that information on administrative tenure can be utilized to attract applicants by appealing to criteria within their high-involvement job search activities. High-involvement applicants proactively seek recruitment content that provides essential job attributes that match their needs and skills and are more apt to be a higher quality candidate. Based upon the study's findings, managers are offered marketing strategy recommendations for tailoring recruiting messages that appeal to high-involvement job seekers.

Academic Freedom and Tenure: Macomb County Community College (Michigan): A Report on a Disciplinary Suspension

Science.gov (United States)

AAUP Bulletin, 1976

1976-01-01

The report of the AAUP Committee A on Academic Freedom and Tenure regarding the one-year disciplinary suspension of Professor Richard William Rosenbaum for taking four days of unauthorized leave of absence is presented. Procedural and substantive issues of the grievance procedures are reviewed. (LBH)

Property rights in a very poor country : tenure insecurity and investment in Ethiopia

OpenAIRE

Ali, Daniel Ayalew; Dercon, Stefan; Gautam, Madhur

2007-01-01

This paper provides evidence from one of the poorest countries of the world that the property rights matter for efficiency, investment, and growth. With all land state-owned, the threat of land redistribution never appears far off the agenda. Land rental and leasing have been made legal, but transfer rights remain restricted and the perception of continuing tenure insecurity remains quite ...

Building a Strong Foundation: Mentoring Programs for Novice Tenure-Track Librarians in Academic Libraries

Science.gov (United States)

Goodsett, Mandi; Walsh, Andrew

2015-01-01

Increasingly, new librarians graduate to face a world of changing technology and new ways of interacting with information. The anxiety of this shifting environment is compounded for tenure-track librarians who must also meet scholarship and instruction requirements that may be unfamiliar to them. One way that librarians can navigate the transition…

Lessons Learned about Post-Tenure Review from the AAHE Peer Review of Teaching Project.

Science.gov (United States)

Taylor, James W.

1999-01-01

Describes use of a strategy adapted from the American Association for Higher Education's Peer Review of Teaching Project, the "reflective memo," to provide backward and forward view of post-tenure reviews in the chemistry department of the University of Wisconsin (Madison). The approach served as a guide in review of research, teaching,…

29 CFR 1625.11 - Exemption for employees serving under a contract of unlimited tenure.

Science.gov (United States)

2010-07-01

... 29 Labor 4 2010-07-01 2010-07-01 false Exemption for employees serving under a contract of unlimited tenure. 1625.11 Section 1625.11 Labor Regulations Relating to Labor (Continued) EQUAL EMPLOYMENT... within the exemption can lawfully be forced to retire on account of age at age 70 (see paragraph (a)(1...

THE EFFECTS OF COMPANY SIZE, COMPANY RISK AND AUDITOR’S REPUTATION ON TENURE: AN ARTIFICIAL ROTATION TESTING

Directory of Open Access Journals (Sweden)

Junaidi

2016-09-01

Full Text Available This study aims to empirically examine the effects of firms’ size, firms’ risk, and auditors’ reputations on tenure in an artificial rotation. The phenomenon of artificial auditor (audit firm rotations in Indonesia is an interesting topic, deserving further study. Artificial auditor rotations indicate a condition in which, conceptually, there has been a change of auditor that makes the relationship between the auditor and the client end, but in effect, the relationship is still going on. Regulations for mandatory auditor rotations causes audit firms or their partners to cheat the system by changing the name of their firm, or partners, to allow them to continue auditing the same client. This research samples 110 companies listed on the Indonesian Stock Exchange between 2000 and 2010, which were obtained using a purposive sampling method. The results of a statistical test indicate that a company’s size significantly influences the tenure. The variables of firms’ risk and auditors’ reputations do not have significant effects on tenure, statistically. This research is expected to contribute both theoretically and practically, especially to the regulations on auditors’ rotations. Auditing quality is an important factor that must be maintained by the auditor profession, to maintain the independence of auditors. In the auditing practices in Indonesia, regulators should consider the artificial rotation phenomenon that occurs in Indonesia, so the practice of auditing can run better.

The implications of new forest tenure reforms and forestry property markets for sustainable forest management and forest certification in China.

Science.gov (United States)

Chen, Juan; Innes, John L

2013-11-15

This study examines issues existing in the southern collective forests in China, particularly prior to the implementation of new forest tenure reforms, such as continued illegal logging and timber theft, inadequate availability of finance and inconsistent forest-related policies. Such problems are believed to be hindering the adoption of sustainable forest management (SFM) and forest certification by forest farmers in China. Two strategies were introduced by the Chinese government with the purpose of addressing these issues, namely forest tenure reforms and their associated supporting mechanism, forestry property markets. Through two case studies in southern China, we investigated the effectiveness of the two strategies as well as their implications for the adoption of SFM and forest certification. The two cases were Yong'an in Fujian province and Tonggu in Jiangxi province. Personal interviews with open-ended questions were conducted with small-scale forest farmers who had already benefited from the two strategies as well as market officers working for the two selected forestry property markets. The study identified eight issues constraining the potential adoption of SFM and certification in China, including limited finance, poorly developed infrastructure and transport systems, insecure forest tenures, inconsistent forest policies, low levels of awareness, illegal forest management practices, lack of local cooperative organizations, and inadequate knowledge and technical transfer. We found that the new forest tenure reforms and forestry property markets had generally fulfilled their original objectives and had the capacity to assist in addressing many of the issues facing forests prior to the reforms. Copyright © 2013 Elsevier Ltd. All rights reserved.

Affective Organizational Commitment and Citizenship Behavior: Linear and Non-linear Moderating Effects of Organizational Tenure

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Ng, Thomas W. H.; Feldman, Daniel C.

2011-01-01

Utilizing a meta-analytical approach for testing moderating effects, the current study investigated organizational tenure as a moderator in the relation between affective organizational commitment and organizational citizenship behavior (OCB). We observed that, across 40 studies (N = 11,416 respondents), the effect size for the relation between…

Tenure-Track Science Faculty and the 'Open Access Citation Effect'

Directory of Open Access Journals (Sweden)

R. Christopher Doty

2013-02-01

Full Text Available INTRODUCTION The observation that open access (OA articles receive more citations than subscription-based articles is known as the OA citation effect (OACE. Implicit in many OACE studies is the belief that authors are heavily invested in the number of citations their articles receive. This study seeks to determine what influence the OACE has on the decision-making process of tenure-track science faculty when they consider where to submit a manuscript for publication. METHODS Fifteen tenure-track faculty members in the Departments of Biology and Chemistry at the University of North Carolina at Chapel Hill participated in semi-structured interviews employing a variation of the critical incident tecnique. RESULTS Seven of the fifteen faculty members said they would consider making a future article freely-available based on the OACE. Due to dramatically different expectations with respect to the size of the OACE, however, only one of them is likely to seriously consider the OACE when deciding where to submit their next manuscript for publication. DISCUSSION Journal reputation and audience, and the quality of the editorial and review process are the most important factors in deciding where to submit a manuscript for publication. Once a subset of journals has satisfied these criteria, financial and access issues compete with the OACE in making a final decision. CONCLUSION In order to increase the number of OA materials, librarians should continue to emphasize depositing pre- and post-prints in disciplinary and institutional repositories and retaining the author rights prior to publication in order to make it possible to do so.

Women's Land Tenure Security and Household Human Capital: Evidence from Ethiopia's Land Certification.

Science.gov (United States)

Muchomba, Felix M

2017-10-01

This paper examines the impact of Ethiopia's gendered land certification programs on household consumption of healthcare, food, education, and clothing. Ethiopia embarked on a land tenure reform program in 1998, after years of communism during which all land was nationalized. The reform began in Tigray region where land certificates were issued to household heads, who were primarily male. In a second phase carried out in 2003-2005, three other regions issued land certificates jointly to household heads and spouses, presenting variation in land tenure security by gender. Results using household panel data show that joint land certification to spouses was accompanied by increased household consumption of healthcare and homegrown food and decreased education expenditure, compared to household-head land certification. Joint land certification was also accompanied by increased consumption of women's and girls' clothing, and decreased men's clothing expenditures indicating results may be explained by a shift in the gender balance of power within households. Analysis on the incidence and duration of illness indicates that increased healthcare expenditures after joint land certification may be due to joint certification households seeking more effective treatment than head-only certification households for household members who fell ill or suffered injuries.

Straddling Cultures, Identities, and Inconsistencies: Voices of Pre-Tenure Faculty of Color in Educational Leadership

Science.gov (United States)

Martinez, Melissa A.; Welton, Anjalé D.

2017-01-01

Drawing on the notions of biculturalism, or double consciousness, and hybridity, this qualitative study explored how 12 pre-tenure faculty of color (FOC) in the field of educational leadership working at universities in the United States negotiated their self-identified cultural identities within their predominantly White departments. Results…

Enhancing forest tenure reforms through more responsive regulations

Directory of Open Access Journals (Sweden)

Anne M Larson

2012-01-01

Full Text Available Forest tenure reforms have offered new opportunities for communities to obtain formal rights to forests and forest benefits, but at the same time a variety of limitations are placed on livelihood options. This article draws on several case studies of reforms in Africa, Asia and Latin America to analyse the regulations accompanying reforms. It identifies three types of regulations, namely rules that limit areas available to local communities; rules that delineate conservation areas and impose related limits on use; and bureaucratic requirements for permits and management plans, which restrict the commercial use and marketing of valuable forest products. It discusses problems with these regulations, and proposes a simple framework for identifying ways to promote regulations that work for forest conservation but are more responsive to the needs of communities and forests.

How Do Young Tenured Professors Benefit from a Mentor? Effects on Management, Motivation and Performance

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van der Weijden, Inge; Belder, Rosalie; van Arensbergen, Pleun; van den Besselaar, Peter

2015-01-01

Do young tenured professors who receive mentorship differ from those without mentorship in terms of motivation, scholarly performance, and group management practice? We conducted a survey among research group leaders in the biomedical and health sciences in the Netherlands, to study the effects of mentorship. Our results show that mentorship…

Alleged Death Threats, a Hunger Strike, and a Department at Risk Over a Tenure Decision.

Science.gov (United States)

Leatherman, Courtney

2000-01-01

Reports on a tenure controversy within the Indiana University department of Near Eastern Languages and Cultures that has involved possible death threats, a hunger strike, and controversy over the department's continued existence. For now the professor, an expert on Islamic philosophy, remains at the institution, other faculty have left, and…

Beliefs about Post-Tenure Review; the Influence of Autonomy, Collegiality, Career Stage, and Institutional Context

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O'Meara, Kerry Ann

2004-01-01

This article draws upon the literature on academic culture and the academic profession to provide a context for beliefs about post-tenure review. Schein's (1992) theory of organizational culture and Kuh & Whitt's (1988) application of cultural theory to higher education settings divides culture into a conceptual hierarchy comprised of three…

[Disclosure of a mental disorder in the workplace and work accommodations: two factors associated with job tenure of people with severe mental disorders].

Science.gov (United States)

Corbière, M; Villotti, P; Toth, K; Waghorn, G

2014-06-01

Job tenure for people with severe mental disorders (e.g., schizophrenia) remains a stumbling-block to their work integration. However, the length of job tenure can vary according to the workplace (e.g., provided resources) and the work context (e.g., regular market, social firms). This gap can be explained in part by diverse organisational components, particularly the implementation of work accommodations, which is related to the disclosure of the mental disorder in the workplace. Indeed, in the scientific literature, the principal reason associated with disclosure is in regards to requesting work accommodations. The main objective of this paper is to increase our understanding of the relationships between these three concepts - disclosure of a mental disorder, work accommodations and natural supports, and job tenure - by reviewing the specialized literature and presenting the work of the authors of this paper. To do so, the authors will address the following questions: How do we define 'disclosure' of a mental disorder in the workplace and what are the strategies to consider before disclosing? What is the decision-making process related to disclosure in the workplace? How are the three concepts - disclosure of the mental disorder in the workplace, work accommodations and job tenure - intertwined? Finally, how can employment specialists facilitate the work integration of people with severe mental disorders by considering the three concepts mentioned above? Results from a review of the literature show that disclosure of a mental disorder is a dialectical process that goes beyond the question: to tell or not to tell? In fact, it is not a single binary decision. Several components are associated with the disclosure concept, and can be summarized by the questions: What, how, when and to whom to disclose his/her mental condition? Reasons for disclosing his/her mental disorder in the workplace are numerous, characterized by personal, interpersonal and work environmental

Who Publishes in Top-Tier Library Science Journals? An Analysis by Faculty Status and Tenure

Science.gov (United States)

Galbraith, Quinn; Smart, Elizabeth; Smith, Sara D.; Reed, Megan

2014-01-01

This study analyzes the status and background of authors publishing in high-impact library science journals. Twenty-three high-impact journals were selected in this study by both quantitative and qualitative measures, while the analysis of author background focuses on whether the author holds a faculty status position with a tenure track. This…

Time to Tenure in Spanish Universities: An Event History Analysis

Science.gov (United States)

Sanz-Menéndez, Luis; Cruz-Castro, Laura; Alva, Kenedy

2013-01-01

Understanding how institutional incentives and mechanisms for assigning recognition shape access to a permanent job is important. This study, based on data from questionnaire survey responses and publications of 1,257 university science, biomedical and engineering faculty in Spain, attempts to understand the timing of getting a permanent position and the relevant factors that account for this transition, in the context of dilemmas between mobility and permanence faced by organizations. Using event history analysis, the paper looks at the time to promotion and the effects of some relevant covariates associated to academic performance, social embeddedness and mobility. We find that research productivity contributes to career acceleration, but that other variables are also significantly associated to a faster transition. Factors associated to the social elements of academic life also play a role in reducing the time from PhD graduation to tenure. However, mobility significantly increases the duration of the non-tenure stage. In contrast with previous findings, the role of sex is minor. The variations in the length of time to promotion across different scientific domains is confirmed, with faster career advancement for those in the Engineering and Technological Sciences compared with academics in the Biological and Biomedical Sciences. Results show clear effects of seniority, and rewards to loyalty, in addition to some measurements of performance and quality of the university granting the PhD, as key elements speeding up career advancement. Findings suggest the existence of a system based on granting early permanent jobs to those that combine social embeddedness and team integration with some good credentials regarding past and potential future performance, rather than high levels of mobility. PMID:24116199

Time to tenure in Spanish universities: an event history analysis.

Science.gov (United States)

Sanz-Menéndez, Luis; Cruz-Castro, Laura; Alva, Kenedy

2013-01-01

Understanding how institutional incentives and mechanisms for assigning recognition shape access to a permanent job is important. This study, based on data from questionnaire survey responses and publications of 1,257 university science, biomedical and engineering faculty in Spain, attempts to understand the timing of getting a permanent position and the relevant factors that account for this transition, in the context of dilemmas between mobility and permanence faced by organizations. Using event history analysis, the paper looks at the time to promotion and the effects of some relevant covariates associated to academic performance, social embeddedness and mobility. We find that research productivity contributes to career acceleration, but that other variables are also significantly associated to a faster transition. Factors associated to the social elements of academic life also play a role in reducing the time from PhD graduation to tenure. However, mobility significantly increases the duration of the non-tenure stage. In contrast with previous findings, the role of sex is minor. The variations in the length of time to promotion across different scientific domains is confirmed, with faster career advancement for those in the Engineering and Technological Sciences compared with academics in the Biological and Biomedical Sciences. Results show clear effects of seniority, and rewards to loyalty, in addition to some measurements of performance and quality of the university granting the PhD, as key elements speeding up career advancement. Findings suggest the existence of a system based on granting early permanent jobs to those that combine social embeddedness and team integration with some good credentials regarding past and potential future performance, rather than high levels of mobility.

Time to tenure in Spanish universities: an event history analysis.

Directory of Open Access Journals (Sweden)

Luis Sanz-Menéndez

Full Text Available Understanding how institutional incentives and mechanisms for assigning recognition shape access to a permanent job is important. This study, based on data from questionnaire survey responses and publications of 1,257 university science, biomedical and engineering faculty in Spain, attempts to understand the timing of getting a permanent position and the relevant factors that account for this transition, in the context of dilemmas between mobility and permanence faced by organizations. Using event history analysis, the paper looks at the time to promotion and the effects of some relevant covariates associated to academic performance, social embeddedness and mobility. We find that research productivity contributes to career acceleration, but that other variables are also significantly associated to a faster transition. Factors associated to the social elements of academic life also play a role in reducing the time from PhD graduation to tenure. However, mobility significantly increases the duration of the non-tenure stage. In contrast with previous findings, the role of sex is minor. The variations in the length of time to promotion across different scientific domains is confirmed, with faster career advancement for those in the Engineering and Technological Sciences compared with academics in the Biological and Biomedical Sciences. Results show clear effects of seniority, and rewards to loyalty, in addition to some measurements of performance and quality of the university granting the PhD, as key elements speeding up career advancement. Findings suggest the existence of a system based on granting early permanent jobs to those that combine social embeddedness and team integration with some good credentials regarding past and potential future performance, rather than high levels of mobility.

Enact, Discard, and Transform: A Critical Race Feminist Perspective on Professional Socialization among Tenured Black Female Faculty

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Sulé, Venice Thandi

2014-01-01

Through an analysis informed by critical race feminism, this paper examines the intersection of professional socialization and agency among tenured Black female faculty at Predominantly White Institutions (PWIs). Professional socialization entails the transmission and reproduction of professional norms. However, within PWIs, professional…

Interest Congruency as a Moderator of the Relationships between Job Tenure and Job Satisfaction and Mental Health

Science.gov (United States)

Klein, Kenneth; Wiener, Yoash

1977-01-01

In a sample of 54 middle managers, significant moderator effects were found for the mental health indices of self-esteem, life-satisfaction, and overall mental health and for satisfaction with supervision. These indices correlated positively with job tenure for high congruency individuals. For low congruency individuals, the obtained correlations…

Development, evaluation, and utility of a peer evaluation form for online teaching.

Science.gov (United States)

Gaskamp, Carol D; Kintner, Eileen

2014-01-01

Formative assessment of teaching by peers is an important component of quality improvement for educators. Teaching portfolios submitted for promotion and tenure are expected to include peer evaluations. Faculty resources designed for peer evaluation of classroom teaching are often inadequate for evaluating online teaching. The authors describe development, evaluation, and utility of a new peer evaluation form for formative assessment of online teaching deemed relevant, sound, feasible, and beneficial.

Things I Wish They Had Told Me: Advice From a Newly Tenured Faculty Member From a Small, Liberal Arts College

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Sheldon, Peter

2002-04-01

I followed a relatively unique path to tenure. I knew I wanted to teach at a small, liberal arts college, so I chose to “post-doc” as a visiting faculty member instead of doing research. I continued to do research as I taught, but teaching was the main focus. I feel that the path that I followed, the opportunities for research and having found tremendously effective mentors in my three years as a visiting faculty member put me in the perfect position to find the job I wanted. I am now in the fourth year of my first tenure-track job, and find myself with tenure. Randolph-Macon Woman’s College is a nationally ranked liberal arts college in central VA with 720 students. The Department of Physics and Astronomy offers both a BA and a BS in physics, and in struggling to stay alive with only two faculty members, I have actually managed to keep going with a few research and grant opportunities. I hope that my experiences will strike a chord with some of the audience, and my experiences can help others to decide what is and what is not important to them in the finding and holding of a faculty job. Other topics that could be covered include juggling responsibilities, seeking grants, dealing with colleagues, interacting with students, and learning to teach.

Tenure Track Policy Increases Representation of Women in Senior Academic Positions, but Is Insufficient to Achieve Gender Balance

NARCIS (Netherlands)

Bakker, M.M.; Jacobs, M.H.

2016-01-01

Underrepresentation of women in senior positions is a persistent problem in universities worldwide, and a wide range of strategies to combat this situation is currently being contemplated. One such strategy is the introduction of a tenure track system, in which decisions to promote scientific staff

Boreal Forest Carbon Sequestration Strategies : a Case Study of the Little Red River Cree First Nation Land Tenures

NARCIS (Netherlands)

Krcmar, E.; Kooten, van G.C.

2005-01-01

In this paper, creation of carbon offset and emission reduction credits are examined from the perspective of the Little Red River Cree Nation (LRRCN), a forest tenure holder in northern Alberta. Carbon credits are produced under three scenarios: (1) carbon uptake in forest ecosystems, with

The joint choice of tenure, dwelling type and size

DEFF Research Database (Denmark)

Frenkel, Amnon; Bendit, Eduard; Kaplan, Sigal

Real-estate market trends regarding housing preferences for tenure, dwelling type and size carry long term implications for cities’ spatial development and compactness. Much attention have been given to the impact of household demographics and socio-economic characteristics on joint housing choices...... not ignore the ordered nature of apartment size. To the best of our knowledge, first application of the MNL-OR model in the context of housing preferences. The model is applied to a data sample of 833 knowledge-workers in the Tel-Aviv metropolitan region in Israel. The effect of lifestyle on housing...... preferences is particularly interesting in the case of knowledge-workers due to their high income and car ownership which allow high residential mobility, and due to the importance they attribute to lifestyle. The data were collected by means of a revealed-preference web-based survey that elicited information...

Indigenous land tenure and tropical forest management in Latin America

Energy Technology Data Exchange (ETDEWEB)

Davis, S.H. (The World Bank, Environment Department, Washington DC (United States)); Wali, A. (University of Maryland, College of Behavioral and Social Sciences, Department of Anthropology, College Park, MD (United States))

1994-12-01

Indigenous peoples have received much attention as potential resource managers of threatened tropical forest ecosystems. Using data from Latin America, this article argues that fundamental changes need to take place in the legal recognition and demarcation of indigenous territories in order for this potential to be fulfilled. A comparison is made between different national land-tenure models for forest-dwelling indigenous peoples and a new model proposed by Latin American indigenous organizations. This comparison suggests that not only do indigenous peoples need to be provided with some degree of control over their territories and resources, but there needs to be a new type of partnership among indigenous peoples, the scientific community, national governments and international development agencies for the management of tropical forests. 37 refs, 3 tabs

It is our land. Human rights and land tenure reform in Namaqualand, South Africa

OpenAIRE

Wisborg, Poul

2006-01-01

‘It is our land’: Human rights and land tenure reform in Namaqualand, South Africa Secure access to resources is a universal condition of human well-being and is of considerable concern in contemporary human rights discourse, though often neglected in policy and practice. In this respect the South African constitutional guarantees and policies concerning land reform are of wide interest. The main goal of this study is to contribute to the theoretical and empirical understanding of la...

The Role of Person-Environment Fit in the Job Satisfaction and Tenure Intentions of African American Employees

Science.gov (United States)

Lyons, Heather Z.; O'Brien, Karen M.

2006-01-01

In light of speculation that the determinants of job satisfaction and tenure for African American employees may not be adequately captured by the theory of work adjustment (TWA; Dawis & Lofquist, 1984), in the present study the authors tested assumptions of the TWA with an African American sample by (a) examining the strength of fit-satisfaction…

The erosion of academic tenure in the U.S. and its ties to public neoliberal anti-intellectualism

Directory of Open Access Journals (Sweden)

Virginia R. Dominguez

2017-07-01

Full Text Available This essay examines the erosion of tenure in the U.S. academy and its connections to the spread of neoliberal capitalist ideology in U.S. colleges and universities. It also explores how this affects anthropology departments since only a small part of anthropology is ever considered part of the STEM fields.

The joint choice of tenure, dwelling type, size and location: the effect of home-oriented versus culture-oriented lifestyle

DEFF Research Database (Denmark)

Frenkel, Amnon; Kaplan, Sigal

2014-01-01

This study investigates knowledge-workers’ housing preferences in terms of tenure, dwelling type, location and size. The analysis is conducted by applying a joint multinomial-logit ordered-response model to the housing choices of knowledgeworkers residing in the Tel-Aviv metropolitan region and w...

African American Female Professors' Strategies for Successful Attainment of Tenure and Promotion at Predominately White Institutions: It Can Happen

Science.gov (United States)

Jones, Brandolyn; Hwang, Eunjin; Bustamante, Rebecca M.

2015-01-01

In their pursuit of tenure and promotion, African American female faculty members continue to prevail over workplace adversities such as ridicule, marginalization, alienation, isolation, and lack of information. In this descriptive phenomenological study, the lived experiences of five African American female professors who successfully navigated…

Statutory Requirements of Teacher Contract Laws: A Comparison of the 50 States' Continuing Contract and Teacher Tenure Laws.

Science.gov (United States)

Gorkom, Kris Van

This publication summarizes and compares legal provisions covering teacher tenure and contracts for each of the 50 states. The report is organized in three sections. Section 1 presents a summary comparison of the provisions of Washington's teacher contract law with corresponding statutory requirements of the other 49 states. Section 2 identifies…

Guidelines for Field Research Reports

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

Jean-Claude Dumais

Your Award Grant Agreement specifies the number of reports required throughout your tenure as well as the due dates for such reports. The form of your report will vary, depending on the nature of your research, your methodological approach, and your participation in related activities such as conferences, etc. However ...

"I Expect to Be Engaged as an Equal": Collegiality Expectations of Full-Time, Non-Tenure-Track Faculty Members

Science.gov (United States)

Alleman, Nathan F.; Haviland, Don

2017-01-01

Nationally, non-tenure-track faculty (NTTF) represent the new majority. Efforts to move the full-time NTTF role from expendable labor to sustainable professional position have led to improvements in policy and working conditions at many institutions. Still, the profession broadly has just begun to grapple with the implications of this shifting…

Determinants of longer job tenure among home care aides: what makes some stay on the job while others leave?

Science.gov (United States)

Butler, Sandra S; Brennan-Ing, Mark; Wardamasky, Sara; Ashley, Alison

2014-03-01

An inadequate supply of direct care workers and a high turnover rate in the workforce has resulted in a "care gap" in our long-term care system. As people are increasingly choosing community-based care, retention of home care workers is particularly important. The mixed-method study described herein explored determinants of longer job tenure for home care aides (n = 261). Study participants were followed for 18 months, completing two mail surveys and one telephone interview each. Predictors of longer job tenure included older age, living rurally, lower physical function, higher wages, a greater sense of autonomy on the job, and less frequent feelings of personal accomplishment. Thematic analysis of telephone interviews revealed long-term stayers to be less concerned about low wages and inconsistent hours than those who left their jobs within a year; both groups of workers reported high levels of job satisfaction. Policy implications of study findings are discussed.

Assessing scientists for hiring, promotion, and tenure.

Science.gov (United States)

Moher, David; Naudet, Florian; Cristea, Ioana A; Miedema, Frank; Ioannidis, John P A; Goodman, Steven N

2018-03-01

Assessment of researchers is necessary for decisions of hiring, promotion, and tenure. A burgeoning number of scientific leaders believe the current system of faculty incentives and rewards is misaligned with the needs of society and disconnected from the evidence about the causes of the reproducibility crisis and suboptimal quality of the scientific publication record. To address this issue, particularly for the clinical and life sciences, we convened a 22-member expert panel workshop in Washington, DC, in January 2017. Twenty-two academic leaders, funders, and scientists participated in the meeting. As background for the meeting, we completed a selective literature review of 22 key documents critiquing the current incentive system. From each document, we extracted how the authors perceived the problems of assessing science and scientists, the unintended consequences of maintaining the status quo for assessing scientists, and details of their proposed solutions. The resulting table was used as a seed for participant discussion. This resulted in six principles for assessing scientists and associated research and policy implications. We hope the content of this paper will serve as a basis for establishing best practices and redesigning the current approaches to assessing scientists by the many players involved in that process.

Assessing scientists for hiring, promotion, and tenure

Science.gov (United States)

Naudet, Florian; Cristea, Ioana A.; Miedema, Frank; Ioannidis, John P. A.; Goodman, Steven N.

2018-01-01

Assessment of researchers is necessary for decisions of hiring, promotion, and tenure. A burgeoning number of scientific leaders believe the current system of faculty incentives and rewards is misaligned with the needs of society and disconnected from the evidence about the causes of the reproducibility crisis and suboptimal quality of the scientific publication record. To address this issue, particularly for the clinical and life sciences, we convened a 22-member expert panel workshop in Washington, DC, in January 2017. Twenty-two academic leaders, funders, and scientists participated in the meeting. As background for the meeting, we completed a selective literature review of 22 key documents critiquing the current incentive system. From each document, we extracted how the authors perceived the problems of assessing science and scientists, the unintended consequences of maintaining the status quo for assessing scientists, and details of their proposed solutions. The resulting table was used as a seed for participant discussion. This resulted in six principles for assessing scientists and associated research and policy implications. We hope the content of this paper will serve as a basis for establishing best practices and redesigning the current approaches to assessing scientists by the many players involved in that process. PMID:29596415

To Curl up or Relax? That Is the Question: Tenured Black Female Faculty Navigation of Black Hair Expression in Academia

Science.gov (United States)

Gray, Sylvia

2017-01-01

One area of identity that challenges dominant ideals of professional, neat, or appropriate appearance is Black hair. Although Black hair expression is frequent in media, politics, and pop culture, there still remains a perceived stigma surrounding its presence in positions and environments (e.g. tenure positions or predominantly White…

Tenured Teacher Dismissal in New York: Education Law § 3020-a "Disciplinary Procedures and Penalties." Working Paper 2014-1

Science.gov (United States)

Stevens, Katharine B.

2014-01-01

The two recently-filed New York lawsuits claiming that teacher tenure laws violate children's constitutional right to a "sound basic education" are finally dragging the long-obscure Section 3020-a of the state's Education Law into the spotlight. This attention is badly overdue because for decades § 3020-a has impeded efforts to ensure a…

Effect of social mobility in family financial situation and housing tenure on mental health conditions among South Australian adults: results from a population health surveillance system, 2009 to 2011.

Science.gov (United States)

Dal Grande, Eleonora; Chittleborough, Catherine R; Wu, Jing; Shi, Zumin; Goldney, Robert D; Taylor, Anne W

2015-07-17

To assess the association of socioeconomic position (SEP), measured by family financial situation and housing tenure in childhood and adulthood, with mental health conditions in adulthood. Representative cross-sectional population data were collected using a risk factor surveillance system in South Australia, Australia. Each month, a random sample were selected from the Electronic White Pages. Participants aged 25 years and above (n = 10429) were asked about doctor diagnosed anxiety, stress or depression, suicidal ideation, psychological distress, demographic and socioeconomic factors using Computer Assisted Telephone Interviewing (CATI). Social mobility measures were derived from housing status and perceived financial situation during adulthood and at 10 years of age. The prevalence of psychological distress was 8.1 %, current diagnosed mental health condition was 14.8 % and suicidal ideation was 4.3 %. Upward mobility in family financial situation and housing tenure was experienced by 28.6 % and 19.3 %, of respondents respectively. Downward mobility was experienced by 9.4 % for housing tenure and 11.3 % for family financial situation. In the multivariable analysis, after adjusting for age, sex, childhood family structure and adult education, downward social mobility and stable low SEP (both childhood and adulthood), in terms of both housing tenure and financial situation, were positively associated with all three mental health conditions. People with low SEP in adulthood had poor mental health outcomes regardless of their socioeconomic circumstances in childhood. Policies to improve SEP have the potential to reduce mental health conditions in the population.

Does personality influence job acquisition and tenure in people with severe mental illness enrolled in supported employment programs?

Science.gov (United States)

Fortin, Guillaume; Lecomte, Tania; Corbière, Marc

2017-06-01

When employment difficulties in people with severe mental illness (SMI) occur, it could be partly linked to issues not specific to SMI, such as personality traits or problems. Despite the fact that personality has a marked influence on almost every aspect of work behavior, it has scarcely been investigated in the context of employment for people with SMI. We aimed to evaluate if personality was more predictive than clinical variables of different competitive work outcomes, namely acquisition of competitive employment, delay to acquisition and job tenure. A sample of 82 people with a SMI enrolled in supported employment programs (SEP) was recruited and asked to complete various questionnaires and interviews. Statistical analyses included logistic regressions and survival analyses (Cox regressions). Prior employment, personality problems and negative symptoms are significantly related to acquisition of a competitive employment and to delay to acquisition whereas the conscientiousness personality trait was predictive of job tenure. Our results point out the relevance of personality traits and problems as predictors of work outcomes in people with SMI registered in SEP. Future studies should recruit larger samples and also investigate these links with other factors related to work outcomes.

Assessing the Potential of Using Value-Added Estimates of Teacher Job Performance for Making Tenure Decisions. Working Paper 31

Science.gov (United States)

Goldhaber, Dan; Hansen, Michael

2010-01-01

Reforming teacher tenure is an idea that appears to be gaining traction with the underlying assumption being that one can infer to a reasonable degree how well a teacher will perform over her career based on estimates of her early-career effectiveness. Here we explore the potential for using value-added models to estimate performance and inform…

Labour Mobility and Housing: The Impact of Housing Tenure and Housing Affordability on Labour Migration in the Czech Republic

Czech Academy of Sciences Publication Activity Database

Lux, Martin; Sunega, Petr

2012-01-01

Roč. 49, č. 3 (2012), s. 489-504 ISSN 0042-0980 R&D Projects: GA ČR GA403/09/1915 Institutional research plan: CEZ:AV0Z70280505 Keywords : housing * housing policy * housing tenure Subject RIV: AO - Sociology, Demography Impact factor: 1.493, year: 2012 http://usj.sagepub.com/content/early/2011/05/20/0042098011405693

FURTHER INVESTIGATION INTO THE RELATIONSHIP BETWEEN QUIT RATES AND THE WAGE-TENURE PROFILE IN JAPANESE MANUFACTURING

OpenAIRE

太田, 聰一; OHKUSA, Yasushi

1996-01-01

We examine the relationship between actual quit rates and the slope of wage-tenure profile. The results obtained clarify that there is a negative relationship between these series when we use the definition with monetary units. Conversely, the slope defined in terms of growth is found to be positively correlated with the quit rate. As the theory predicts a negative relationship between these variables, it seems reasonable to conclude from the results that the definition of the slope in moneta...

Questão fundiária em áreas protegidas: Uma experiência no Parque Estadual da Pedra Branca (PEPB, Rio de Janeiro, Brasil / Land tenure in protected areas: a case study in the State Park of Pedra Branca, Rio de Janeiro, Brazil

Directory of Open Access Journals (Sweden)

Allan Yu Iwama

2014-04-01

Full Text Available The land tenure has been a challenge for the management of protected areas in Brazil, mainly those located in urban areas, such as the ‘Pedra Branca’ State Park (PEPB in the west of Rio de Janeiro city. To ensure an adequate management of UC, this paper presents a land tenure analysis for support the Management Plan of PEPB. Based on the secondary data and application of structured questionnaires (316 interviews, representing 29% of the total estimated housing on the land tenure in areas inside/around of PEPB boundaries, seeking for some key elements to support the management of PEPB. This survey identified six zones (Z with some types of occupation in the study area. The results showed that there are diversified occupations, such as residents with high, medium and low income, including ‘favelas’, subsistence agricultures and temporary residents. This work pointed out to a complexity related to the land tenure in protected areas and highlights the required elements: (i systematic data survey for the complete registration of properties in PEPB; (ii organization of a multi-interdisciplinary working groups to solve land tenure problems, (iii implementation of environmental education and communication programs, seeking explanation on the PEPB conservation as a factor of improving the quality of life, (iv agreements between the residents of the Park and policy makers to minimize the conflicts caused by the land tenure in PEPB.

Level of Awareness and Basic Knowledge Related to Radiation Protection Based on Academic Qualification and Service Tenure in Malaysian Nuclear Agency

International Nuclear Information System (INIS)

Munira Shaikh Nasir

2015-01-01

Effective radiation protection program is vital to ensure the safety of workers involved in work related to radiation. This objective of this research was to determine the level of awareness towards radiation protection among the workers at Malaysian Nuclear Agency. Questionnaire forms containing questions related to relevant work experience and knowledge of radiation safety were distributed to a group of identified radiation workers. The hypothesis of this study is that all workers involved have high levels of awareness and basic knowledge as they work in an institution which activities frequently and routinely involve radiation. The result of this research show that the level of awareness and knowledge of the respondents were at a good level, with an average overall score of 87.2% showed a high level of awareness among respondents. Overall, highest academic qualifications did not affect the level of knowledge (p > 0.05). In contrast, service tenure affects their level of knowledge (p < 0.05). (author)

Promotion and Tenure: Application of Scholarship of Teaching and Learning, and Scholarship of Engagement Criteria to Health Professions Education

Directory of Open Access Journals (Sweden)

Shilpa J. Register

2018-03-01

Discussion: More research on the application of the scholarship of discovery, the scholarship of integration, and the scholarship of application is needed in health professions education to further guide faculty and administrators. Investigation into the discrepancy in rank within tenured faculty in educations is an area that would bring insight into current challenges and barriers, allowing educational researchers the ability to research and develop effective strategies.

A comparative study of behavioural, physical and mental health status between term-limited and tenure-tracking employees in a population of Japanese male researchers.

Science.gov (United States)

Nakao, M; Yano, E

2006-04-01

Traditional lifelong employment systems have been changing rapidly in Japan. The aim of this study was to assess the health impacts of term-limited employment systems that have recently been introduced into Japanese academic institutes. Cross-sectional. A total of 514 male researchers (275 term limited and 239 tenure track) were compared in terms of behavioural, physical and mental status at annual health examinations. At these examinations, working hours and health-related lifestyles were examined using a self-completed questionnaire. Clinical structured interviews of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) were used to detect major depression. The term-limited researchers tended to work longer hours (Pbreakfast less regularly (P0.05) between the two groups, fatigue was more prevalent (P=0.027) in the term-limited researchers than in the tenure-track researchers, adjusting for the effects of age. Compared with colleagues working in the same laboratories, the term-limited researchers worked longer hours, irrespective of fatigue, whereas only the fatigued tenure-track researchers worked longer hours. In the total sample, the fatigued researchers tended to belong to laboratories where their colleagues, on average, worked longer hours, compared with the non-fatigued researchers. These results imply that the term-limited researchers suffered more from fatigue, due to longer working hours, than their colleagues, and that organized, rather than personal, interventions with respect to the working environment may be effective in reducing overload in such workplaces.

Mixed tenure communities as a policy instrument for educational outcomes in a deprived urban context?

Science.gov (United States)

Robison, Oonagh; Kearns, Ade; Gray, Linsay; Bond, Lyndal; Henderson, Marion

2016-05-03

This article considers mixed community strategies, enacted through planning and regeneration policies, as a policy approach to the improvement of educational outcomes in schools. Analysis is undertaken of educational outcomes across secondary schools in Glasgow. The level of owner occupation in the catchment is positively associated with both examination results at S4 and positive destinations post-school, particularly at the more deprived end of the school spectrum. The results suggest that tenure mix may be both directly and indirectly related to school performance, with neighbourhood context effects not being entirely mediated through the school context.

Urbanization, land tenure security and vector-borne Chagas disease

Science.gov (United States)

Levy, Michael Z.; Barbu, Corentin M.; Castillo-Neyra, Ricardo; Quispe-Machaca, Victor R.; Ancca-Juarez, Jenny; Escalante-Mejia, Patricia; Borrini-Mayori, Katty; Niemierko, Malwina; Mabud, Tarub S.; Behrman, Jere R.; Naquira-Velarde, Cesar

2014-01-01

Modern cities represent one of the fastest growing ecosystems on the planet. Urbanization occurs in stages; each stage characterized by a distinct habitat that may be more or less susceptible to the establishment of disease vector populations and the transmission of vector-borne pathogens. We performed longitudinal entomological and epidemiological surveys in households along a 1900 × 125 m transect of Arequipa, Peru, a major city of nearly one million inhabitants, in which the transmission of Trypanosoma cruzi, the aetiological agent of Chagas disease, by the insect vector Triatoma infestans, is an ongoing problem. The transect spans a cline of urban development from established communities to land invasions. We find that the vector is tracking the development of the city, and the parasite, in turn, is tracking the dispersal of the vector. New urbanizations are free of vector infestation for decades. T. cruzi transmission is very recent and concentrated in more established communities. The increase in land tenure security during the course of urbanization, if not accompanied by reasonable and enforceable zoning codes, initiates an influx of construction materials, people and animals that creates fertile conditions for epidemics of some vector-borne diseases. PMID:24990681

Magnetized strange quark matter in f(R, T) gravity with bilinear and special form of time varying deceleration parameter

Science.gov (United States)

Sahoo, P. K.; Sahoo, Parbati; Bishi, Binaya K.; Aygün, Sezgin

2018-04-01

In this paper, we have studied homogeneous and anisotropic locally rotationally symmetric (LRS) Bianchi type-I model with magnetized strange quark matter (MSQM) distribution and cosmological constant Λ in f(R, T) gravity where R is the Ricci scalar and T the trace of matter source. The exact solutions of the field equations are obtained under bilinear and special form of time varying deceleration parameter (DP). Firstly, we have considered two specific forms of bilinear DP with a single parameter of the form: q = α(1-t)/1+t and q = -αt/1+t, which leads to the constant or linear nature of the function based on the constant α. Second one is the special form of the DP as q = - 1 + β/1+aβ. From the results obtained here, one can observe that in the early universe magnetic flux has more effects and it reduces gradually in the later stage. For t → ∞, we get p → -Bc and ρ → Bc. The behaviour of strange quark matter along with magnetic epoch gives an idea of accelerated expansion of the universe as per the observations of the type Ia Supernovae.

Determinants of a City Manager’s Tenure in Office

Directory of Open Access Journals (Sweden)

Bonnie G. Mani

2014-02-01

Full Text Available Appointed officials in municipalities influence policy decisions and the distribution of services that affect everyday life. So stability or turnover of appointed officials is likely to affect efficiency and effectiveness of critical services like police protection, fire fighting and prevention, land use regulation, and public utilities. Seeking to explain the relationship between four groups of variables and appointed officials’ long or short terms in office, quantitative data collected from a random sample of appointed municipal officials in North Carolina were analyzed using hierarchical logistic regression. Tenure in office divided at median years in office was the dichotomous dependent variable. Four groups of independent variables related to the person, the job, the city, and election systems were entered hierarchically in four logistic regression models. Qualitative data collected from the same appointed officials further explain the results of the quantitative analysis. Results show that competence in formulating and implementing budgets and city government experience lead to longer terms in office, higher education leads to shorter terms in office, and political variables have no significant effect on appointed officials’ job security in North Carolina. This is useful information for city managers setting long-term career goals, citizens judging local governments’ service delivery, and elected officials making decisions about appointments and terminations.

PENGARUH EFEKTIVITAS KOMITE AUDIT, KOMITMEN PROFESIONAL, TENURE OF THE AUDIT FIRM, DAN PERSAINGAN ANTAR KANTOR AKUNTAN PUBLIK TERHADAP INDEPENDENSI AKUNTAN PUBLIK: PERSEPSI AUDITOR EKSTERNAL DI SURABAYA

Directory of Open Access Journals (Sweden)

Jimy Abadi

2011-11-01

Full Text Available Each company which is had by public needs public accountant opinion about financialstatement that was prepared by the management. Audit of financial statement is done forincrease financial statement credibility through push down information risk. Stakeholderslook at independent auditor report for the financial statement include reasonable assuranceabout relevance and reliability. But without independence, the attestation function will be nil.In other words, the independence is perhaps the most essential factor in existence of a publicaccounting profession. The goal of this research are to examine and to get empirical evidenceabout influence of audit committee effectiveness, professional commitment, tenure of the auditfirm, and competition among public accountant firms to accountant public independenceaccordance external auditor perception in Surabaya. The analysis model for this researchuses multiple regression analysis. This research uses 91 samples of questionnaire responsefrom staffs of non big four affiliation and non-affiliation CPA firm. The result of this researchis committee audit effectiveness and commitment professional have significant influence topublic accountant independence individually. Tenure of the audit firm doesn’t havesignificant influence to public accountant independence individually. And the competitionamong public accountant firms has significant influence to public accountant independenceindividually for non affiliation CPA firms, while the competition among public accountantfirms doesn’t have significant influence to public accountant independence individually fornon big four affiliation CPA firms. Keywords:public accountant independence, audit committee effectiveness, professionalcommitment, tenure of the audit firm, competition among public accountant firms,external auditor perception

Do Birds of a Feather Flock Together? An Examination of Calling, Congruence, Job Design and Personality as Predictors of Job Satisfaction and Tenure

Science.gov (United States)

Nillsen, C.; Earl, J. K.; Elizondo, F.; Wadlington, P. L.

2014-01-01

This study explored whether congruence, calling, job characteristics or personality were better predictors of job satisfaction and tenure. The sample consisted of 1968 employees across four different job roles: sales engineers (N = 309), graphic designers (N = 383), teachers (N = 481) and clergy (N = 795). Data was collected as part of a selection…

FORMS OF DEVELOPMENT AND LAND TENURE AS IMPROVEMENT TOOLS OF land use planning IN UKRAINE

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Tretyak A.M.

2016-05-01

Full Text Available Transformations which take place now in the the economy of Ukraine, and in particular in agriculture considerably exacerbated organizational and legal problems and organizational and territorial forms of local agricultural enterprises, protection of land ownership rights. Transformation of land relations violated the the traditional forms of organization of agricultural production, reduced the efficiency of capital investmenst in improvement of using and protection of land. Therefore, to improve the efficiency of agricultural land use in conditions of formation of market economy, general urgent of time is an in-depth analysis of the types and forms of land use which have found their consolidation at the legislative level. Land management is carried out throughout the country. It enveloped lands irrespective of unequivocal purpose, ownership and the character of using. But goals and objectives of land management, it’s content may be different. An important feature of land management are and it’s types. The current Land Code of Ukraineas the the Law of Ukraine "On Land Management" don’t contain legislative provisions on division of land management for certain types. Meanwhile, it should be noted, that normative and legal acts on land management of the Soviet period (Fundamentals of land legislation of the USSR and the United Republics 1968. Land codes 1978., 1990, 1992 there are two separate types of it - intereconomic (Modern terminology of A.M. Tretyak - territorial and internaleconomic. Modern practice of the actions in the field of land management as evidenced by about the existence of another and a third type of land management – separational. Each of them is characterized by a specific purpose, carried out at different levels. It would therefore be appropriate, hat separate species of land management und their consolidation and in legislation level. Given that the process of implementation of land management for the object of land

Streamlining Appointment, Promotion, and Tenure Procedures to Promote Early-Career Faculty Success.

Science.gov (United States)

Smith, Shannon B; Hollerbach, Ann; Donato, Annemarie Sipkes; Edlund, Barbara J; Atz, Teresa; Kelechi, Teresa J

2016-01-01

A critical component of the progression of a successful academic career is being promoted in rank. Early-career faculty are required to have an understanding of appointment, promotion, and tenure (APT) guidelines, but many factors often impede this understanding, thwarting a smooth and planned promotion pathway for professional advancement. This article outlines the steps taken by an APT committee to improve the promotion process from instructor to assistant professor. Six sigma's DMAIC improvement model was selected as the guiding operational framework to remove variation in the promotion process. After faculty handbook revisions were made, several checklists developed, and a process review rubric was implemented; recently promoted faculty were surveyed on satisfaction with the process. Faculty opinions captured in the survey suggest increased transparency in the process and perceived support offered by the APT committee. Positive outcomes include a strengthened faculty support framework, streamlined promotion processes, and improved faculty satisfaction. Changes to the APT processes resulted in an unambiguous and standardized pathway for successful promotion. Copyright © 2016 Elsevier Inc. All rights reserved.

Manager Tenure, Internal Control and Strategic Differences%管理者任期、内部控制与战略差异

Institute of Scientific and Technical Information of China (English)

殷治平; 张兆国

2016-01-01

本文运用战略管理理论、委托代理理论和高阶梯队理论，以我国2011—2014年沪深两市A股类上市公司为研究样本，考察了内部控制对战略差异影响以及管理者既有任期和预期任期在这种影响中的调节作用。研究结果表明：内部控制与战略差异呈显著负相关；管理者既有任期在内部控制影响战略差异中的调节作用呈倒U型；管理者预期任期在内部控制影响战略差异中起正向调节作用。进一步研究表明，在非国有上市公司中内部控制与战略差异的负相关以及管理者既有任期的调节作用均比国有上市公司更显著，而管理者预期任期的调节作用则在国有上市公司中更显著。这些研究结论对企业完善内部控制、合理选择管理者聘期、降低战略风险具有一定的启示意义。%Based on strategic management theory, principal⁃agent theory and upper echelons theory, sampling on listed corporations in Shanghai and Shenzhen A stock markets between 2011 - 2014 in China, this paper examines the relationship between internal control and strategic differences from the top management team ’ s perspective�Research shows that:the relationship of internal control quality and strategic differences is negative which means the higher the quality of internal control,the smaller the difference of strategy;The mediation effect of top management team’ s existing tenure on the relationship of internal control and strategic difference is first negative then change to be positive, and which of top management team’ s expected tenure works positively�The relationship between internal control and strategic differences and the mediation effect of top management team ’ s existing tenure on the relationship between internal control and strategic difference in non⁃state⁃owned listing corporation are more significant than that in state⁃owned listing corporation, that of top management team

Why is housing tenure associated with a lower risk of admission to a nursing or residential home? Wealth, health and the incentive to keep 'my home'.

Science.gov (United States)

McCann, Mark; Grundy, Emily; O'Reilly, Dermot

2012-02-01

Previous research has shown that home ownership is associated with a reduced risk of admission to institutional care. The extent to which this reflects associations between wealth and health, between wealth and ability to buy in care or increased motivation to avoid admission related to policies on charging is unclear. Taking account of the value of the home, as well as housing tenure, may provide some clarification as to the relative importance of these factors. To analyse the probability of admission to residential and nursing home care according to housing tenure and house value. Cox regression was used to examine the association between home ownership, house value and risk of care home admissions over 6 years of follow-up among a cohort of 51 619 people aged 65 years or older drawn from the Northern Ireland Longitudinal Study, a representative sample of ≈28% of the population of Northern Ireland. Results 4% of the cohort (2138) was admitted during follow-up. Homeowners were less likely than those who rented to be admitted to care homes (HR 0.77, 95% CI 0.70 to 0.85, after adjusting for age, sex, health, living arrangement and urban/rural differences). There was a strong association between house value/tenure and health with those in the highest valued houses having the lowest odds of less than good health or limiting long-term illness. However, there was no difference in probability of admission according to house value; HRs of 0.78 (95% CI 0.67 to 0.90) and 0.81 (95% CI 0.70 to 0.95), respectively, for the lowest and highest value houses compared with renters. The requirement for people in the UK with capital resources to contribute to their care is a significant disincentive to institutional admission. This may place an additional burden on carers.

Does Academic Blogging Enhance Promotion and Tenure? A Survey of US and Canadian Medicine and Pediatric Department Chairs.

Science.gov (United States)

Cameron, Christian Blake; Nair, Vinay; Varma, Manu; Adams, Martha; Jhaveri, Kenar D; Sparks, Matthew A

2016-06-23

Electronic educational (e-learning) technology usage continues to grow. Many medical journals operate companion blogs (an application of e-learning technology) that enable rapid dissemination of scientific knowledge and discourse. Faculty members participating in promotion and tenure academic tracks spend valuable time and effort contributing, editing, and directing these medical journal blogs. We sought to understand whether chairs of medicine and pediatric departments acknowledge blog authorship as academic achievement. The authors surveyed 267 chairs of US and Canadian medicine and pediatric departments regarding their attitudes toward the role of faculty participation in e-learning and blogging in the promotion and tenure process. The survey completion rate was 22.8% (61/267). A majority of respondents (87%, 53/61) viewed educational scholarship as either important or very important for promotion. However, only 23% (14/61) perceived importance to faculty effort in producing content for journal-based blogs. If faculty were to participate in blog authorship, 72% (44/61) of surveyed chairs favored involvement in a journal-based versus a society-based or a personal (nonaffiliated) blog. We identified a "favorable group" of chairs (19/59, 32%), who rated leadership roles in e-learning tools as important or very important, and an "unfavorable group" of chairs (40/59, 68%), who rated leadership roles in e-learning tools as somewhat important or not important. The favorable group were more likely to be aware of faculty bloggers within their departments (58%, 11/19 vs 25%, 10/40), viewed serving on editorial boards of e-learning tools more favorably (79%, 15/19 vs 31%, 12/39), and were more likely to value effort spent contributing to journal-based blogs (53%, 10/19 vs 10%, 4/40). Our findings demonstrate that although the majority of department chairs value educational scholarship, only a minority perceive value in faculty blogging effort.

Population health and urban form : a review of the literature

International Nuclear Information System (INIS)

2004-11-01

A review examining the links between public health and living spaces was presented. The aim of the review was to explore whether different urban forms created communities that encouraged healthy living and resulted in a healthier population as well as to suggest avenues and approaches for further research of the subject in British Columbia. The historical links between public health and community planning were examined. A conceptual model of the linkages of urban form and population health was developed and used to identify ways in which urban form and population health are linked. Areas of concern include vehicle emissions, water quality and heat build-up as well as noise pollution. Issues concerning health inequalities related to income and access to health services were examined, as well as the role that urban form plays as a barrier to physical activity. Findings indicated that there is a strong correlation between urban form and health. Lower density urban forms that require a vehicle generated more miles travelled by car with more traffic crashes and higher risks to pedestrians and cyclists. A growing body of evidence has indicated that community contacts are scarcer in low density areas. In addition, low density dwellers seemed to have higher stress levels. Car dependent lifestyles had negative impacts on children's play, growth and development. Urban forms which promoted a range of housing options in terms of affordability, tenure and type allowed people to remain within their neighbourhoods. Disadvantaged groups fared better in denser areas where there were more public facilities. 62 refs. 1 tab., 2 figs

Motivation fatigue as a threat to innovation

DEFF Research Database (Denmark)

Mattsson, Jan; Helmersson, Helge; Stetler, Katarina

2016-01-01

What do employees need in order to be innovative? In this paper, we explored how employees with different lengths of tenure within the research and development (R&D) department of a company in the automotive industry answer this question. We found that the needs vary depending on the length...... of the employee’s tenure. New employees view innovation as an organisational work issue and employees with longer tenure seek the support of management in changing the work situation themselves in a way that will enhance innovation. In contrast, employees who have been with the company over 10 years show signs...

Varying constants, black holes, and quantum gravity

International Nuclear Information System (INIS)

Carlip, S.

2003-01-01

Tentative observations and theoretical considerations have recently led to renewed interest in models of fundamental physics in which certain 'constants' vary in time. Assuming fixed black hole mass and the standard form of the Bekenstein-Hawking entropy, Davies, Davis and Lineweaver have argued that the laws of black hole thermodynamics disfavor models in which the fundamental electric charge e changes. I show that with these assumptions, similar considerations severely constrain 'varying speed of light' models, unless we are prepared to abandon cherished assumptions about quantum gravity. Relaxation of these assumptions permits sensible theories of quantum gravity with ''varying constants,'' but also eliminates the thermodynamic constraints, though the black hole mass spectrum may still provide some restrictions on the range of allowable models

Effect of age, gender, economic group and tenure on thermal comfort: A field study in residential buildings in hot and dry climate with seasonal variations

Energy Technology Data Exchange (ETDEWEB)

Indraganti, Madhavi; Rao, Kavita Daryani [Architecture Department, Jawaharlal Nehru Architecture and Fine Arts University, Hyderabad (India)

2010-03-15

Energy consumption in Indian residential buildings is one of the highest and is increasing phenomenally. Indian standards specify comfort temperatures between 23 and 26 C for all types of buildings across the nation. However, thermal comfort research in India is very limited. A field study in naturally ventilated apartments was done in 2008, during the summer and monsoon seasons in Hyderabad in composite climate. This survey involved over 100 subjects, giving 3962 datasets. They were analysed under different groups: age, gender, economic group and tenure. Age, gender and tenure correlated weakly with thermal comfort. However, thermal acceptance of women, older subjects and owner-subjects was higher. Economic level of the subjects showed significant effect on the thermal sensation, preference, acceptance and neutrality. The comfort band for lowest economic group was found to be 27.3-33.1 C with the neutral temperature at 30.2 C. This is way above the standard. This finding has far reaching energy implications on building and HVAC systems design and practice. Occupants' responses for other environmental parameters often depended on their thermal sensation, often resulting in a near normal distribution. The subjects displayed acoustic and olfactory obliviousness due to habituation, resulting in higher satisfaction and acceptance. (author)

On the data between the ratio of new supply houses at four tenures in Japan. At 47 prefectures and 80 cities; 300,000 and more population on 1995; Shinsetsu chako jutaku no riyo kankeibetsu deta. 47 todofuken and 80 toshi (jinko 300,000 nin 'heisei 7 {center_dot} kokucho' ijo narabini kencho shozaishi)(1993 {approx} 1997)

Energy Technology Data Exchange (ETDEWEB)

Iida, Toshihiko; Kojina, Kyoji

1999-03-01

On the owned tenure, the average construction-started ratio spreaded from 1.15 houses in Amagasaki-shi to 6.30 houses in Hamamatsu-shi during 1983 {approx} 1987, the same values spreaded from 1.42 houses in Amagasaki-shi to 5083 houses in Akita-shi during 1988 {approx} 1992 and the same values spreaded from 1.44 houses in Osaka-shi to 6.67 houses in Aomori-shi during 1993 {approx} 1997. 2nd on the rental tenure, the average construction-started ratio spreaded from 1.88 house in Sakai-shi to 14.32 houses in Ichikawa-shi during 1983 {approx} 1987, the same values spreaded from 3.72 houses in Sakai-shi to 13.93 houses in Kawasaki-shi during 1988 {approx} 1992 and from 2.82 houses in Yokosuka-shi to 9.88 houses in Sendai-shi during 1993 {approx} 1997, espicialy 13.17 houses in Nishinomiya-shi. 3rd on the issued tenure, the average construction-started ratio spreaded from 0.05 houses in Maebashi-shi 0.45 houses in Mito-shi during 1983 {approx} 1992 and from 0.02 houses in Naha-shi to 0.74 houses in Omiya-shi during 1993 {approx} 1997, espicialy 1.00 houses in Nishinomiya-shi. 4th on the for-sale tenure, the average construction-started ratio spraeded from 0.36 houses in Kurashiki-shi 5.65 houses in Kobe-shi during 1983 {approx} 1987, the same values spreaded from 0.89 houses in Iwaki-shi and Fukui-shi to 6.14 houses in Fukuoka-shi during 1988 {approx} 1992 and from 0.63 houses in Kurashiki-shi to 7.51 houses in Urawa-shi during 1993 {approx} 1997, especially 8.66 houses in Nishinomiya-shi. The construction-started hoses of the rental tenure were leading during this fifteen years, but the construction-started houses of the for-sale tenure were increasing recently in Japan, though the same values of the owned tenure were continuing during this periods. At 80 cities the construction-started ratio of the rental tenure spreaded from 2.61 houses in Kitakyushu-shi to 12.01 houses in Hachioji-shi on 1993, the same values spreaded from 2.41 houses in Toyota-shi to 9.98 houses in

Auditing versus consultancy: a critique of the EU law reforms on the new form of auditing

Directory of Open Access Journals (Sweden)

H. Kubra Kandemir

2016-09-01

Full Text Available Auditors used to serve the interest of the shareholders only. However, there have been significant changes in terms of auditors’ role and their function. Auditors are now expected to verify financial statements, but at the same time give an assurance regarding the financial sustainability of the entity. Regarding the latter role, audit firms provide consulting services, including risk assessment and management services. However, the law does not assign the latter role to external auditors. This situation results in an expectations gap in relation to both the role of the auditors and the scope of the external auditing. In addition, the growing economic importance of consulting and the long years of auditor tenure is likely to impair auditor independence. This paper submits that the new form of auditing is not problematic but creates issues. First, the expectations between the users of the financial reports and auditors are wider. Second, auditors’ independence is damaged due to the long years of auditor tenure and dependence of non-audit fees generated from consultancy services that not related to audit. The recent law reforms issued by the European Commission has brought some important provisions in terms of filling the expectations gap, reinforcing auditor independence and reducing the familiarity threat. EU’s relatively strict rules on provision of non-audit services and audit firm rotation are expected to have an important impact in the audit market. A critical analysis of the new EU law is submitted with some policy recommendations.

Career Development and Adults with Moderate to Severe Mental Retardation.

Science.gov (United States)

Wadsworth, John; Cocco, Karen

Lifelong career development activities may assist persons with more severe forms of mental retardation in achieving occupational tenure. Occupational tenure is important if individuals are to move away from a succession of entry-level employment. Adaptive career development strategies and techniques may prevent job dissatisfaction and poor…

Electricity Futures Prices : Time Varying Sensitivity to Fundamentals

NARCIS (Netherlands)

S-E. Fleten (Stein-Erik); R. Huisman (Ronald); M. Kilic (Mehtap); H.P.G. Pennings (Enrico); S. Westgaard (Sjur)

2014-01-01

textabstractThis paper provides insight in the time-varying relation between electricity futures prices and fundamentals in the form of prices of contracts for fossil fuels. As supply curves are not constant and different producers have different marginal costs of production, we argue that the

Stolypin’s Agrarian Reform in Kyiv Province: Antecedents and Consequences for Peasant Land Tenure

Directory of Open Access Journals (Sweden)

L. Ihnatova

2016-07-01

Full Text Available The article considers the state of the Ukrainian peasantry tenure in the province of Kyiv. After the reforms of the Russian government in 1861. The majority of the peasants received small plots of land. The reform was carried out with the intention to preserve the estates of the landlords. Attention is drawn to the fact that in the early twentieth century, the plight of the peasants led to their active participation in the revolutionary events of 1905. Analyzes the attempts of the government and landowners to solve the peasant question of handing over land to rent. But this approach to the Kiev province was ineffective. Therefore, the Russian government is trying to address this issue at the legislative level. November 9, 1906 a law was passed that abolished the peasant community and allowed it to strengthen private property. But in the province of Kyiv, these actions of the Russian government have been ineffective. Land hunger of the peasants remained a major problem, because the allocation of the farm required a certain amount of land. Therefore, most of the peasants were forced to sell their land and migrate.

Pengaruh Audit Quality, Audit Tenure, Audit Report Lag, dan Profitabilitas terhadap Opini Audit Going Concern pada Perusahaan Manufaktur yang Terdaftar di Bursa Efek Indonesia Periode 2010-2013

OpenAIRE

Grace N. Rgg, Hermin

2015-01-01

The purpose of this research is to analyze the effect of audit quality using proxy auditor industry specialization, audit tenure, audit report lag, and profitability using proxy net profit margin ratio on going concern opinion. Population used in this research is manufacturing companies listed in Indonesian Directory Exchange from 2010-2013. This research uses 20 sample companies achieved using purposive sampling. Data used in this research is secondary data are financial statement and indepe...

PENGARUH AUDIT TENURE, UKURAN AUDITOR, SPESIALISASI AUDIT DAN AUDIT CAPACITY STRESS TERHADAP MANAJEMEN LABA (Studi Empiris pada Perusahaan Manufaktur yang listed di BEI tahun 2010-2015

Directory of Open Access Journals (Sweden)

Deddy Kurniawansyah

2016-11-01

Full Text Available The purpose for this research is to test audit tenure, auditor size, audit specialization industry, and audit capacity stress to earning management manufacture industry listed in the BEI in 2010-2015. In this research, we use leverage, firms size, and ROA as Control variable. This study population was manufacture industry listed in the BEI in 2010-2015. This population use criteria population by 703 annual reports manufacture industy. The sampling used in this study a sensus method. Source of data is secondary data, obtained from annual reports of manufacture industry in BEI. This study used multiple regretion analysis to analysis data with the help of the program Partial Last Square (PLS. The results obtained in this study is audit tenure, and audit capacity stress has a positive effect on earning management manufacture industry. Auditor size, and audit specialization industry has a negative effect on earning management manufacture industry. For control variable, the results obtained is leverage, firms size, and ROA has a positive effect on earning management manufacture industry. The results provide more informed basis for investors to be more selective in investing their funds. To reduce earnings management practices in companies should principals switched auditors periodically or less than 3 years, and using scale big four auditors, and has specialized audit industry.

H ∞ synchronization of the coronary artery system with input time-varying delay

International Nuclear Information System (INIS)

Li Xiao-Meng; Zhao Zhan-Shan; Sun Lian-Kun; Zhang Jing

2016-01-01

This paper investigates the H ∞ synchronization of the coronary artery system with input delay and disturbance. We focus on reducing the conservatism of existing synchronization strategies. Base on the triple integral forms of the Lyapunov–Krasovskii functional (LKF), we utilize single and double integral forms of Wirtinger-based inequality to guarantee that the synchronization feedback controller has good performance against time-varying delay and external disturbance. The effectiveness of our strategy can be exhibited by simulations under the different time-varying delays and different disturbances. (paper)

Biofilm-forming bacteria with varying tolerance to peracetic acid from a paper machine.

Science.gov (United States)

Rasimus, Stiina; Kolari, Marko; Rita, Hannu; Hoornstra, Douwe; Salkinoja-Salonen, Mirja

2011-09-01

Biofilms cause runnability problems in paper machines and are therefore controlled with biocides. Peracetic acid is usually effective in preventing bulky biofilms. This study investigated the microbiological status of a paper machine where low concentrations (≤ 15 ppm active ingredient) of peracetic acid had been used for several years. The paper machine contained a low amount of biofilms. Biofilm-forming bacteria from this environment were isolated and characterized by 16S rRNA gene sequencing, whole-cell fatty acid analysis, biochemical tests, and DNA fingerprinting. Seventy-five percent of the isolates were identified as members of the subclades Sphingomonas trueperi and S. aquatilis, and the others as species of the genera Burkholderia (B. cepacia complex), Methylobacterium, and Rhizobium. Although the isolation media were suitable for the common paper machine biofoulers Deinococcus, Meiothermus, and Pseudoxanthomonas, none of these were found, indicating that peracetic acid had prevented their growth. Spontaneous, irreversible loss of the ability to form biofilm was observed during subculturing of certain isolates of the subclade S. trueperi. The Sphingomonas isolates formed monoculture biofilms that tolerated peracetic acid at concentrations (10 ppm active ingredient) used for antifouling in paper machines. High pH and low conductivity of the process waters favored the peracetic acid tolerance of Sphingomonas sp. biofilms. This appears to be the first report on sphingomonads as biofilm formers in warm water using industries.

The end of mass homeownership? Changes in labour markets and housing tenure opportunities across Europe.

Science.gov (United States)

Arundel, Rowan; Doling, John

2017-01-01

With continued economic growth and expanding mortgage markets, until recently the pattern across advanced economies was of growing homeownership sectors. The Great Financial Crisis (GFC) has however, undercut this growth resulting in the contraction of homeownership access in many countries and the revival of private renting. This paper argues that these tenure changes are not solely a consequence of the GFC, and therefore, reversible once long-term growth returns. Rather, they are the consequences of more fundamental changes especially in labour markets. The very financialisation that fuelled the growth of homeownership has also led to a hollowing out of well-paid, secure jobs-exactly those that fit best with the taking of housing loans. We examine longer-term declines in labour market security across Europe from before the GFC, identifying an underlying correlation between deteriorated labour market conditions and homeownership access for young adults. While variations exist across European countries, there is evidence of common trends. We argue that the GFC both accelerated pre-existing labour insecurity dynamics and brought an end to offsetting such dynamics through the expansion of credit access with the likelihood of a return to an era of widespread homeownership growth starkly decreased.

Novel forms of colloidal self-organization in temporally and spatially varying external fields: from low-density network-forming fluids to spincoated crystals

Science.gov (United States)

Yethiraj, Anand

2010-03-01

External fields affect self-organization in Brownian colloidal suspensions in many different ways [1]. High-frequency time varying a.c. electric fields can induce effectively quasi-static dipolar inter-particle interactions. While dipolar interactions can provide access to multiple open equilibrium crystal structures [2] whose origin is now reasonably well understood, they can also give rise to competing interactions on short and long length scales that produce unexpected low-density ordered phases [3]. Farther from equilibrium, competing external fields are active in colloid spincoating. Drying colloidal suspensions on a spinning substrate produces a ``perfect polycrystal'' - tiny polycrystalline domains that exhibit long-range inter-domain orientational order [4] with resultant spectacular optical effects that are decoupled from single-crystallinity. High-speed movies of drying crystals yield insights into mechanisms of structure formation. Phenomena arising from multiple spatially- and temporally-varying external fields can give rise to further control of order and disorder, with potential application as patterned (photonic and magnetic) materials. [4pt] [1] A. Yethiraj, Soft Matter 3, 1099 (2007). [2] A. Yethiraj, A. van Blaaderen, Nature 421, 513 (2003). [3] A.K. Agarwal, A. Yethiraj, Phys. Rev. Lett ,102, 198301 (2009). [4] C. Arcos, K. Kumar, W. Gonz'alez-Viñas, R. Sirera, K. Poduska, A. Yethiraj, Phys. Rev. E ,77, 050402(R) (2008).

U.S. publication trends in social and administrative pharmacy: implications for promotion and tenure.

Science.gov (United States)

Kangethe, Anne; Franic, Duska M; Huang, Ming-Yi; Huston, Sally; Williams, Chakita

2012-01-01

There is no consensus on the preferred approach to assess journal quality. Procedures previously used include journal acceptance or rejection policies, impact factors, number of subscribers, citation counts, whether the articles were refereed or not, and journals cited in books within the discipline. This study built on the work of previous authors by using a novel approach to assess journal quality in social and administrative pharmacy (SAdP). To determine U.S. SAdP faculty perceptions of prestigious journals for their research, SAdP faculty perceptions of prestigious journals by their promotion and tenure (P&T) committees, and current research trends in SAdP. A census of U.S. colleges and schools of pharmacy was conducted using an e-mailed survey and an open-ended approach requiring respondents to list their preferred journals. Seventy-nine SAdP faculty reported that the 5 most prestigious journals were JAMA, New England Journal of Medicine, Health Affairs, Health Services Research, and Medical Care. These journals were selected because respondents wished to seek broad readership. Results of this study can be used as a guide by U.S. SAdP faculty and P&T committees to assess the quality of publications by pharmacy administration faculty with the caveat being that pharmacy versus nonpharmacy journals will be chosen based on the fit of the article with the audience. Copyright © 2012 Elsevier Inc. All rights reserved.

Conceptual Analysis: The Charcoal-Agriculture Nexus to Understand the Socio-Ecological Contexts Underlying Varied Sustainability Outcomes in African Landscapes

Directory of Open Access Journals (Sweden)

Miyuki Iiyama

2017-06-01

Full Text Available The production of charcoal is an important socio-economic activity in sub-Saharan Africa (SSA. Charcoal production is one of the leading drivers of rural land-use changes in SSA, although the intensity of impacts on the multi-functionality of landscapes varies considerably. Within a given landscape, charcoal production is closely interconnected to agriculture production both as major livelihoods, while both critically depend on the same ecosystem services. The interactions between charcoal and agricultural production systems can lead to positive synergies of impacts, but will more often result in trade-offs and even vicious cycles. Such sustainability outcomes vary from one site to another due to the heterogeneity of contexts, including agricultural production systems that affect the adoption of technologies and practices. Trade-offs or cases of vicious cycles occur when one-off resource exploitation of natural trees for charcoal production for short-term economic gains permanently impairs ecosystem functions. Given the fact that charcoal, as an important energy source for the growing urban populations and an essential livelihood for the rural populations, cannot be readily substituted in SSA, there must be policies to support charcoal production. Policies should encourage sustainable technologies and practices, either by establishing plantations or by encouraging regeneration, whichever is more suitable for the local environment. To guide context-specific interventions, this paper presents a new perspective—the charcoal-agriculture nexus—aimed at facilitating the understanding of the socio-economic and ecological interactions of charcoal and agricultural production. The nexus especially highlights two dimensions of the socio-ecological contexts: charcoal value chains and tenure systems. Combinations of the two are assumed to underlie varied socio-economic and ecological sustainability outcomes by conditioning incentive mechanisms to affect

Reasserting the commons: Pastoral contestations of private and state lands in East Africa

Directory of Open Access Journals (Sweden)

John G. Galaty

2016-09-01

Full Text Available The theory that land holding is inexorably evolving from common to private or state tenure is challenged by facts on the ground that this paper will examine. ‘Tenure’ is interpreted both in terms of formal law and informal practices. While the association between privatization and land fragmentation is clear, property theory has influenced privatization so the process cannot be used to validate the evolutionary model of transitions from open access to common property to private property. Although in many settings common and state property has given way to privatization, in other cases private or state property has reverted to common holdings. A dynamic tenure model would demonstrate the conditions under which tenure transitions occur between common, private and state property, as the balance between transaction and exclusion costs shifts, or when the boundaries of tenure forms weaken to allow open access to occur. Examining three scenes of tenure transitions involving Kenyan pastoralists (Laikipia County, the Rift Valley, Narok County and Kajiado County, this paper examines cases in which transaction and exclusion dynamics – which are metaphors for the institutional effects of social and territorial relations- lead to changing land-use practices and tenure transitions. In semi-arid pastoral regions, we find more fluid systems of tenure than the inexorable spread of privatization through formalized land rights and increasing land fragmentation would have suggested should occur in the 21st century.

Disclosure of diagnosis of multiple sclerosis in the workplace positively affects employment status and job tenure.

Science.gov (United States)

Kirk-Brown, A K; Van Dijk, P A; Simmons, R D; Bourne, M P; Cooper, B K

2014-06-01

For many employees with multiple sclerosis (MS), disclosure of their diagnosis at work is seen as a high-risk strategy that might lead to diminished perceptions of their capabilities by supervisors and colleagues, if not outright discrimination. The consequence of this mistrust surrounding the disclosure process is that employees with MS may leave it until too late to effectively manage symptoms at work. The objective of this paper is to statistically evaluate the relationship between disclosure of diagnosis at work and maintenance of employment. Three annual, large-sample self-report surveys of MS patients prospectively examined the relationship between disclosure of diagnosis at work and employment status. A total of 1438 people responded to all three surveys. Of employed persons in 2010 (n = 946), 673 also responded to the 2012 survey. Of these 673 respondents 564 were still employed. People who had disclosed their MS status to an employer were more likely to remain in employment in Year 3. The effect of disclosure in predicting employment status remained after controlling for age, gender, hours worked and level of disability. This study provides the first empirical support for the positive role of disclosure in maintaining employment status, measured both as job retention and tenure in current employment. © The Author(s) 2013.

Local Feature Learning for Face Recognition under Varying Poses

DEFF Research Database (Denmark)

Duan, Xiaodong; Tan, Zheng-Hua

2015-01-01

In this paper, we present a local feature learning method for face recognition to deal with varying poses. As opposed to the commonly used approaches of recovering frontal face images from profile views, the proposed method extracts the subject related part from a local feature by removing the pose...... related part in it on the basis of a pose feature. The method has a closed-form solution, hence being time efficient. For performance evaluation, cross pose face recognition experiments are conducted on two public face recognition databases FERET and FEI. The proposed method shows a significant...... recognition improvement under varying poses over general local feature approaches and outperforms or is comparable with related state-of-the-art pose invariant face recognition approaches. Copyright ©2015 by IEEE....

Time-varying linear control for tiltrotor aircraft

Directory of Open Access Journals (Sweden)

Jing ZHANG

2018-04-01

Full Text Available Tiltrotor aircraft have three flight modes: helicopter mode, airplane mode, and transition mode. A tiltrotor has characteristics of highly nonlinear, time-varying flight dynamics and inertial/control couplings in its transition mode. It can transit from the helicopter mode to the airplane mode by tilting its nacelles, and an effective controller is crucial to accomplish tilting transition missions. Longitudinal dynamic characteristics of the tiltrotor are described by a nonlinear Lagrange-form model, which takes into account inertial/control couplings and aerodynamic interferences. Reference commands for airspeed velocity and attitude in the transition mode are calculated dynamically by visiting a command library which is founded in advance by analyzing the flight envelope of the tiltrotor. A Time-Varying Linear (TVL model is obtained using a Taylor-expansion based online linearization technique from the nonlinear model. Subsequently, based on an optimal control concept, an online optimization based control method with input constraints considered is proposed. To validate the proposed control method, three typical tilting transition missions are simulated using the nonlinear model of XV-15 tiltrotor aircraft. Simulation results show that the controller can be used to control the tiltrotor throughout its operating envelop which includes a transition flight, and can also deal with vertical gust disturbances. Keywords: Constrained optimal control, Inertia/control couplings, Tiltrotor aircraft, Time-varying control, Transition mode

Frontal Neurons Modulate Memory Retrieval across Widely Varying Temporal Scales

Science.gov (United States)

Zhang, Wen-Hua; Williams, Ziv M.

2015-01-01

Once a memory has formed, it is thought to undergo a gradual transition within the brain from short- to long-term storage. This putative process, however, also poses a unique problem to the memory system in that the same learned items must also be retrieved across broadly varying time scales. Here, we find that neurons in the ventrolateral…

A serial mediation model of workplace social support on work productivity: the role of self-stigma and job tenure self-efficacy in people with severe mental disorders.

Science.gov (United States)

Villotti, Patrizia; Corbière, Marc; Dewa, Carolyn S; Fraccaroli, Franco; Sultan-Taïeb, Hélène; Zaniboni, Sara; Lecomte, Tania

2017-09-12

Compared to groups with other disabilities, people with a severe mental illness face the greatest stigma and barriers to employment opportunities. This study contributes to the understanding of the relationship between workplace social support and work productivity in people with severe mental illness working in Social Enterprises by taking into account the mediating role of self-stigma and job tenure self-efficacy. A total of 170 individuals with a severe mental disorder employed in a Social Enterprise filled out questionnaires assessing personal and work-related variables at Phase-1 (baseline) and Phase-2 (6-month follow-up). Process modeling was used to test for serial mediation. In the Social Enterprise workplace, social support yields better perceptions of work productivity through lower levels of internalized stigma and higher confidence in facing job-related problems. When testing serial multiple mediations, the specific indirect effect of high workplace social support on work productivity through both low internalized stigma and high job tenure self-efficacy was significant with a point estimate of 1.01 (95% CI = 0.42, 2.28). Continued work in this area can provide guidance for organizations in the open labor market addressing the challenges posed by the work integration of people with severe mental illness. Implications for Rehabilitation: Work integration of people with severe mental disorders is difficult because of limited access to supportive and nondiscriminatory workplaces. Social enterprise represents an effective model for supporting people with severe mental disorders to integrate the labor market. In the social enterprise workplace, social support yields better perceptions of work productivity through lower levels of internalized stigma and higher confidence in facing job-related problems.

Child-Langmuir flow with periodically varying anode voltage

International Nuclear Information System (INIS)

Rokhlenko, A.

2015-01-01

Using the Lagrangian technique, we study settled Child-Langmuir flows in a one dimensional planar diodes whose anode voltages periodically vary around given positive values. Our goal is to find analytically if the average currents in these systems can exceed the famous Child-Langmuir limit found for the stationary current a long time ago. The main result of our study is that in a periodic quasi-stationary regime the average current can be larger than the Child-Langmuir maximum even by 50% compared with its adiabatic average value. The cathode current in this case has the form of rectangular pulses which are formed by a very special triangular voltage modulation. This regime, i.e., periodicity, shape of pulses, and their amplitude, needs to be carefully chosen for the best performance

Anistropically varying conductivity in irreversible electroporation simulations.

Science.gov (United States)

Labarbera, Nicholas; Drapaca, Corina

2017-11-01

One recent area of cancer research is irreversible electroporation (IRE). Irreversible electroporation is a minimally invasive procedure where needle electrodes are inserted into the body to ablate tumor cells with electricity. The aim of this paper is to propose a mathematical model that incorporates a tissue's conductivity increasing more in the direction of the electrical field as this has been shown to occur in experiments. It was necessary to mathematically derive a valid form of the conductivity tensor such that it is dependent on the electrical field direction and can be easily implemented into numerical software. The derivation of a conductivity tensor that can take arbitrary functions for the conductivity in the directions tangent and normal to the electrical field is the main contribution of this paper. Numerical simulations were performed for isotropic-varying and anisotropic-varying conductivities to evaluate the importance of including the electrical field's direction in the formulation for conductivity. By starting from previously published experimental results, this paper derived a general formulation for an anistropic-varying tensor for implementation into irreversible electroporation modeling software. The anistropic-varying tensor formulation allows the conductivity to take into consideration both electrical field direction and magnitude, as opposed to previous published works that only took into account electrical field magnitude. The anisotropic formulation predicts roughly a five percent decrease in ablation size for the monopolar simulation and approximately a ten percent decrease in ablation size for the bipolar simulations. This is a positive result as previously reported results found the isotropic formulation to overpredict ablation size for both monopolar and bipolar simulations. Furthermore, it was also reported that the isotropic formulation overpredicts the ablation size more for the bipolar case than the monopolar case. Thus, our

Visual search for motion-form conjunctions: is form discriminated within the motion system?

Science.gov (United States)

von Mühlenen, A; Müller, H J

2001-06-01

Motion-form conjunction search can be more efficient when the target is moving (a moving 45 degrees tilted line among moving vertical and stationary 45 degrees tilted lines) rather than stationary. This asymmetry may be due to aspects of form being discriminated within a motion system representing only moving items, whereas discrimination of stationary items relies on a static form system (J. Driver & P. McLeod, 1992). Alternatively, it may be due to search exploiting differential motion velocity and direction signals generated by the moving-target and distractor lines. To decide between these alternatives, 4 experiments systematically varied the motion-signal information conveyed by the moving target and distractors while keeping their form difference salient. Moving-target search was found to be facilitated only when differential motion-signal information was available. Thus, there is no need to assume that form is discriminated within the motion system.

A perceptual study on dynamical form in music

DEFF Research Database (Denmark)

Hjortkjær, Jens; Nielbo, Frederik

2010-01-01

The concept of dynamical form is presented as a dimen- sion of music perception. Dynamical form refers to the subjective perception of temporal events in music (explo- sive, fading out, rising etc.). In a behavioral experiment listeners were asked to categorize musical excerpts vary- ing in music...

Waste forms for plutonium disposition

International Nuclear Information System (INIS)

Johnson, S.G.; O'Holleran, T.P.; Frank, S.M.; Meyer, M.K.; Hanson, M.; Staples, B.A.; Knecht, D.A.; Kong, P.C.

1997-01-01

The field of plutonium disposition is varied and of much importance, since the Department of Energy has decided on the hybrid option for disposing of the weapons materials. This consists of either placing the Pu into mixed oxide fuel for reactors or placing the material into a stable waste form such as glass. The waste form used for Pu disposition should exhibit certain qualities: (1) provide for a suitable deterrent to guard against proliferation; (2) be of minimal volume, i.e., maximize the loading; and (3) be reasonably durable under repository-like conditions. This paper will discuss several Pu waste forms that display promising characteristics

Wavelet ridge diagnosis of time-varying elliptical signals with application to an oceanic eddy

OpenAIRE

Lilly , J. M.; Gascard , Jean-Claude

2006-01-01

International audience; A method for diagnosing the physical properties of a time-varying ellipse is presented. This essentially involves extending the notion of instantaneous frequency to the bivariate case. New complications, and possibilities, arise from the fact that there are several meaningful forms in which a time-varying ellipse may be represented. A perturbation analysis valid for the near-circular case clarifies these issues. Diagnosis of the ellipse properties may then be performed...

Gender implications of forest product value chains in the Congo basin

NARCIS (Netherlands)

Ingram, V.; Schure, J.M.; Tieguhong, J.C.; Ndoye, O.; Awono, A.; Iponga, D.M.

2014-01-01

Activities and roles in value chains of forest products in the Congo Basin are highly gendered, varying with the product's characteristics, the segment of the chain and customary regulations and norms. High-value products are primarily male-harvested when customary rules govern tenure and access,

Estimating time-varying exposure-outcome associations using case-control data: logistic and case-cohort analyses.

Science.gov (United States)

Keogh, Ruth H; Mangtani, Punam; Rodrigues, Laura; Nguipdop Djomo, Patrick

2016-01-05

Traditional analyses of standard case-control studies using logistic regression do not allow estimation of time-varying associations between exposures and the outcome. We present two approaches which allow this. The motivation is a study of vaccine efficacy as a function of time since vaccination. Our first approach is to estimate time-varying exposure-outcome associations by fitting a series of logistic regressions within successive time periods, reusing controls across periods. Our second approach treats the case-control sample as a case-cohort study, with the controls forming the subcohort. In the case-cohort analysis, controls contribute information at all times they are at risk. Extensions allow left truncation, frequency matching and, using the case-cohort analysis, time-varying exposures. Simulations are used to investigate the methods. The simulation results show that both methods give correct estimates of time-varying effects of exposures using standard case-control data. Using the logistic approach there are efficiency gains by reusing controls over time and care should be taken over the definition of controls within time periods. However, using the case-cohort analysis there is no ambiguity over the definition of controls. The performance of the two analyses is very similar when controls are used most efficiently under the logistic approach. Using our methods, case-control studies can be used to estimate time-varying exposure-outcome associations where they may not previously have been considered. The case-cohort analysis has several advantages, including that it allows estimation of time-varying associations as a continuous function of time, while the logistic regression approach is restricted to assuming a step function form for the time-varying association.

Weighted approximation with varying weight

CERN Document Server

Totik, Vilmos

1994-01-01

A new construction is given for approximating a logarithmic potential by a discrete one. This yields a new approach to approximation with weighted polynomials of the form w"n"(" "= uppercase)P"n"(" "= uppercase). The new technique settles several open problems, and it leads to a simple proof for the strong asymptotics on some L p(uppercase) extremal problems on the real line with exponential weights, which, for the case p=2, are equivalent to power- type asymptotics for the leading coefficients of the corresponding orthogonal polynomials. The method is also modified toyield (in a sense) uniformly good approximation on the whole support. This allows one to deduce strong asymptotics in some L p(uppercase) extremal problems with varying weights. Applications are given, relating to fast decreasing polynomials, asymptotic behavior of orthogonal polynomials and multipoint Pade approximation. The approach is potential-theoretic, but the text is self-contained.

Magnetization reversal through soliton flip in biquadratic ferromagnet with varying exchange interactions

CERN Document Server

Daniel, M

2002-01-01

We study the phenomenon of magnetization reversal in the form of a soliton flip in a biquadratic ferromagnetic spin chain induced by varying bilinear and biquadratic exchange interactions. This is carried out by analysing the evolution of the velocity and amplitude of the soliton using a perturbation analysis.

On generalized scaling laws with continuously varying exponents

International Nuclear Information System (INIS)

Sittler, Lionel; Hinrichsen, Haye

2002-01-01

Many physical systems share the property of scale invariance. Most of them show ordinary power-law scaling, where quantities can be expressed as a leading power law times a scaling function which depends on scaling-invariant ratios of the parameters. However, some systems do not obey power-law scaling, instead there is numerical evidence for a logarithmic scaling form, in which the scaling function depends on ratios of the logarithms of the parameters. Based on previous ideas by Tang we propose that this type of logarithmic scaling can be explained by a concept of local scaling invariance with continuously varying exponents. The functional dependence of the exponents is constrained by a homomorphism which can be expressed as a set of partial differential equations. Solving these equations we obtain logarithmic scaling as a special case. The other solutions lead to scaling forms where logarithmic and power-law scaling are mixed

It Takes a Rooted Village: Networked Resistance, Connected Communities, and Adaptive Responses to Forest Tenure Reform in Northern Thailand

Directory of Open Access Journals (Sweden)

Kimberly Roberts

2016-06-01

Full Text Available Conflicts persist between forest dwelling communities and advocates of forest conservation. In Thailand, a community forestry bill and national park expansion initiatives leave little space for communities. The article analyzes the case of the predominantly ethnic Black Lahu village of Huai Lu Luang in Chiang Rai province that has resisted the threats posed by a community forestry bill and a proposed national park. The villagers reside on a national forest reserve and have no de jure rights to the land. This article argues, however, that through its network rooted in place and connected to an assemblage of civil society, local government, and NGOs, Huai Lu Luang has been able to stall efforts by the Thai government that would detrimentally impact their use of and access to forest resources. Their resistance is best understood not in isolation – as one victimized community resisting threats to their livelihoods – but in connection to place, through dynamic assemblages. A ‘rooted’ networks approach follows the connections and nodes of Huai Lu Luang’s network that influence and aid the village’s attempts to resist forest tenure reform.

EXPLOSIVE FORMING – ECONOMICAL TECHNOLOGY FOR AEROSPACE STRUCTURES

OpenAIRE

Niculae MARIN; Victor GHIZDAVU

2010-01-01

The explosive forming represents a technological alternative for obtaining small-lot parts,with inexpensive and efficient manufacturing preparation. The explosive forming processing methodspresent a series of important advantages, being recommended for the wide-scale application in theaerospace industry. The economic benefit varies from case to case, independent from the part type,manufacturing series and user.

Estimating time-varying exposure-outcome associations using case-control data: logistic and case-cohort analyses

Directory of Open Access Journals (Sweden)

Ruth H. Keogh

2016-01-01

Full Text Available Abstract Background Traditional analyses of standard case-control studies using logistic regression do not allow estimation of time-varying associations between exposures and the outcome. We present two approaches which allow this. The motivation is a study of vaccine efficacy as a function of time since vaccination. Methods Our first approach is to estimate time-varying exposure-outcome associations by fitting a series of logistic regressions within successive time periods, reusing controls across periods. Our second approach treats the case-control sample as a case-cohort study, with the controls forming the subcohort. In the case-cohort analysis, controls contribute information at all times they are at risk. Extensions allow left truncation, frequency matching and, using the case-cohort analysis, time-varying exposures. Simulations are used to investigate the methods. Results The simulation results show that both methods give correct estimates of time-varying effects of exposures using standard case-control data. Using the logistic approach there are efficiency gains by reusing controls over time and care should be taken over the definition of controls within time periods. However, using the case-cohort analysis there is no ambiguity over the definition of controls. The performance of the two analyses is very similar when controls are used most efficiently under the logistic approach. Conclusions Using our methods, case-control studies can be used to estimate time-varying exposure-outcome associations where they may not previously have been considered. The case-cohort analysis has several advantages, including that it allows estimation of time-varying associations as a continuous function of time, while the logistic regression approach is restricted to assuming a step function form for the time-varying association.

Spall behavior of cast iron with varying microstructures

International Nuclear Information System (INIS)

Plume, Gifford; Rousseau, Carl-Ernst

2014-01-01

The spall strength of cast iron with varying microstructures has been investigated using plate impact at moderate speed. Stress history measurements were made with manganin stress gauges embedded between the back face of the specimen and a low impedance polycarbonate backing. Five separate cast irons were tested. Four of these consisted of gray cast iron with graphite in flake form, with three classified as Type VII A2 and the fourth containing a bimodal distribution of Types VII A4 and VII D8. The fifth casting consisted of ductile cast iron with graphite in nodular form, classified as Type I, size class 5. The spall strength for the Type VII A2 gray cast irons varied between 40 and 370 MPa, and that of the additional gray cast iron, between 410 and 490 MPa. The spall strength of the ductile cast iron fell within the range of 0.94–1.2 GPa. It is shown that the spall strength is linked to the damage level at the spall plane, where an increased level of tensile stress is required to generate higher levels of damage. Post mortem analysis was performed on the recovered samples, revealing the graphite phase to be the primary factor governing the spall fracture of cast irons, where crack nucleation is directly correlated to the debonding of graphite from the metal matrix. The average length of graphite found within a casting is linked to the material's strength, where strength increases as a function of decreasing length. The morphology and mean free path of graphite precipitates further govern the subsequent coalescence of initiated cracks to form a complete fracture plane. In cases where graphite spacing is large, increased energy level is required to complete the fracture process. A secondary factor governing the spall fracture of cast irons has also been linked to the microstructure of the metal matrix, with pearlite yielding higher spall strengths than free ferrite.

Spall behavior of cast iron with varying microstructures

Energy Technology Data Exchange (ETDEWEB)

Plume, Gifford; Rousseau, Carl-Ernst, E-mail: rousseau@uri.edu [Mechanical Engineering, University of Rhode Island, 92 Upper College Rd., Kingston, Rhode Island 02881 (United States)

2014-07-21

The spall strength of cast iron with varying microstructures has been investigated using plate impact at moderate speed. Stress history measurements were made with manganin stress gauges embedded between the back face of the specimen and a low impedance polycarbonate backing. Five separate cast irons were tested. Four of these consisted of gray cast iron with graphite in flake form, with three classified as Type VII A2 and the fourth containing a bimodal distribution of Types VII A4 and VII D8. The fifth casting consisted of ductile cast iron with graphite in nodular form, classified as Type I, size class 5. The spall strength for the Type VII A2 gray cast irons varied between 40 and 370 MPa, and that of the additional gray cast iron, between 410 and 490 MPa. The spall strength of the ductile cast iron fell within the range of 0.94–1.2 GPa. It is shown that the spall strength is linked to the damage level at the spall plane, where an increased level of tensile stress is required to generate higher levels of damage. Post mortem analysis was performed on the recovered samples, revealing the graphite phase to be the primary factor governing the spall fracture of cast irons, where crack nucleation is directly correlated to the debonding of graphite from the metal matrix. The average length of graphite found within a casting is linked to the material's strength, where strength increases as a function of decreasing length. The morphology and mean free path of graphite precipitates further govern the subsequent coalescence of initiated cracks to form a complete fracture plane. In cases where graphite spacing is large, increased energy level is required to complete the fracture process. A secondary factor governing the spall fracture of cast irons has also been linked to the microstructure of the metal matrix, with pearlite yielding higher spall strengths than free ferrite.

The impact of housing policies and housing markets on ethnic spatial segregation

DEFF Research Database (Denmark)

Andersen, Hans Skifter; Andersson, Roger; Wessel, Terje

2015-01-01

This paper examines how ethnic segregation is connected to an ethnic division of the housing market and a spatial separation of different housing tenures in four Nordic cities. Explanations for the differences across the cities are found by comparing housing markets and housing policies....... The housing markets are in all four cities ethnically segmented with high concentrations of immigrants in some forms of tenures (especially social/public housing) and low concentrations in others. We further discuss the reasons for the observed pattern. The paper shows that the spatial distribution...... housing, while co-operative housing is crucial in the fourth. It is also shown that a policy of neighbourhood tenure mix in one of the cities has resulted in a relatively low degree of segregation in spite of high concentrations of immigrants in social/public housing....

Scaling Analysis of Author-Level Bibliometric Indicators

DEFF Research Database (Denmark)

Wildgaard, Lorna Elizabeth; Larsen, Birger

2014-01-01

Despite of the concerns from the bibliometric community, evaluation of the individual through bibliometric indices is already performed as a form of ‘pseudo peer review’ in selection of candidates for tenure, in background checks of potential employees’ publicationand citation impact, and in appr......Despite of the concerns from the bibliometric community, evaluation of the individual through bibliometric indices is already performed as a form of ‘pseudo peer review’ in selection of candidates for tenure, in background checks of potential employees’ publicationand citation impact......, and in appraisal of funding applications. We investigate the role of central and isolated indicators in the fields of Astronomy, Environmental Science, Philosophy and Public Health and the effect these have on author-rankings....

EXPLOSIVE FORMING – ECONOMICAL TECHNOLOGY FOR AEROSPACE STRUCTURES

Directory of Open Access Journals (Sweden)

Niculae MARIN

2010-12-01

Full Text Available The explosive forming represents a technological alternative for obtaining small-lot parts,with inexpensive and efficient manufacturing preparation. The explosive forming processing methodspresent a series of important advantages, being recommended for the wide-scale application in theaerospace industry. The economic benefit varies from case to case, independent from the part type,manufacturing series and user.

Constructions of Success in Academia: An Early Career Perspective

Science.gov (United States)

Sutherland, Kathryn A.

2017-01-01

Expectations around success in academia vary, and early career academics often receive conflicting messages about what they should concentrate on to achieve promotion or tenure. Taking a social constructionist approach, this paper considers the constructs of objective and subjective career success in academia and shares the perspectives of early…

Does Auditor Tenure Reduce Audit Quality?

OpenAIRE

Junaidi, -; Miharjo, Setiyono; Hartadi, Bambang

2012-01-01

Reduced auditor independence and the rise of corporate accounting manipulations have caused trust of the users in audited financial statements to begin to decline, so users of financial statements are questioning whether public accountants are independent parties. This research issue is related to the Decree of the Minister of Finance No. 17 in 2008 about public accountant services. Giving attestation services, in the form of financial statements about an entity, are conducted by the audit fi...

Brown Dwarf Variability: What's Varying and Why?

Science.gov (United States)

Marley, Mark Scott

2014-01-01

Surveys by ground based telescopes, HST, and Spitzer have revealed that brown dwarfs of most spectral classes exhibit variability. The spectral and temporal signatures of the variability are complex and apparently defy simplistic classification which complicates efforts to model the changes. Important questions include understanding if clearings are forming in an otherwise uniform cloud deck or if thermal perturbations, perhaps associated with breaking gravity waves, are responsible. If clouds are responsible how long does it take for the atmospheric thermal profile to relax from a hot cloudy to a cooler cloudless state? If thermal perturbations are responsible then what atmospheric layers are varying? How do the observed variability timescales compare to atmospheric radiative, chemical, and dynamical timescales? I will address such questions by presenting modeling results for time-varying partly cloudy atmospheres and explore the importance of various atmospheric processes over the relevant timescales for brown dwarfs of a range of effective temperatures. Regardless of the origin of the observed variability, the complexity seen in the atmospheres of the field dwarfs hints at the variability that we may encounter in the next few years in directly imaged young Jupiters. Thus understanding the nature of variability in the field dwarfs, including sensitivity to gravity and metallicity, is of particular importance for exoplanet characterization.

75 FR 72847 - Agency Forms Submitted for OMB Review, Request for Comments

Science.gov (United States)

2010-11-26

... Form RRB W-4P annually. The completion time for Form RRB W-4P varies depending on individual circumstances. The estimated average(s) for Form RRB W-4P is 39 minutes for recordkeeping, 24 minutes for...: 3220-0149. Form(s) submitted: RRB-W-4P, Withholding Certificate for Railroad Retirement Monthly Annuity...

Forms of Life

Directory of Open Access Journals (Sweden)

Peter Hacker

2015-10-01

Full Text Available The phrase ‘Lebensform’ (form of life had a long and varied history prior to Wittgenstein’s use of it on a mere three occasions in the Philosophical Investigations. It is not a pivotal concept in Wittgenstein’s philosophy. But it is a minor signpost of a major reorientation of philosophy, philosophy of language and logic, and philosophy of mathematics that Wittgenstein instigated. For Wittgenstein sought to replace the conception of a language as a meaning calculus (Frege, Russell, the Tractatus by an anthropological or ethnological conception. A language is not a class of sentences that can be formed from a set of axioms (definitions, formation and transformation rules and the meanings of which is given by their truth-conditions, but an open-ended series of interlocking language-games constituting a form of life or way of living (a culture. Wittgenstein’s uses of ‘Lebensform’ and its cognates, both in the Investigations and in his Nachlass are severally analysed, and various exegetical misinterpretations are clarified.

Health Assimilation among Hispanic Immigrants in the United States: The Impact of Ignoring Arrival-cohort Effects.

Science.gov (United States)

Hamilton, Tod G; Palermo, Tia; Green, Tiffany L

2015-12-01

A large literature has documented that Hispanic immigrants have a health advantage over their U.S.-born counterparts upon arrival in the United States. Few studies, however, have disentangled the effects of immigrants' arrival cohort from their tenure of U.S. residence, an omission that could produce imprecise estimates of the degree of health decline experienced by Hispanic immigrants as their U.S. tenure increases. Using data from the 1996-to-2014 waves of the March Current Population Survey, we show that the health (i.e., self-rated health) of Hispanic immigrants varies by both arrival cohort and U.S. tenure for immigrants hailing from most of the primary sending countries/regions of Hispanic immigrants. We also find evidence that acculturation plays an important role in determining the health trajectories of Hispanic immigrants. With respect to self-rated health, however, our findings demonstrate that omitting arrival-cohort measures from health assimilation models may result in overestimates of the degree of downward health assimilation experienced by Hispanic immigrants. © American Sociological Association 2015.

The Critical Role of Teacher Incentives in the Northeast States.

Science.gov (United States)

Title, David

This paper discusses a variety of incentives that can make a difference in attracting and retaining high quality teachers. These incentives include salaries, retirement benefits, working conditions, quality of life, tenure and seniority rights, and sick leave. The states in the Northeast vary considerably in their ability to attract quality…

Exploring Teaching Satisfaction of Public High School Teachers: Empirical Evidence from Turkey

Science.gov (United States)

Büyükgöze, Hilal; Gün, Feyza

2017-01-01

The current paper primarily investigates teaching satisfaction of teachers working in public high schools of Ankara. The latter aim of this study is to determine whether teachers' satisfaction levels vary in relation to some demographic variables such as gender, education, type of high school, tenure, marital status, and membership to an…

Two-dimensional phononic crystals with time-varying properties: a multiple scattering analysis

International Nuclear Information System (INIS)

Wright, D W; Cobbold, R S C

2010-01-01

Multiple scattering theory is a versatile two- and three-dimensional method for characterizing the acoustic wave transmission through many scatterers. It provides analytical solutions to wave propagation in scattering structures, and its computational complexity grows logarithmically with the number of scatterers. In this paper we show how the 2D method can be adapted to include the effects of time-varying material parameters. Specifically, a new T-matrix is defined to include the effects of frequency modulation that occurs in time-varying phononic crystals. Solutions were verified against finite difference time domain (FDTD) simulations and showed excellent agreement. This new method enables fast characterization of time-varying phononic crystals without the need to resort to lengthy FDTD simulations. Also, the method of combining T-matrices to form the T-supermatrix remains unchanged provided that the new matrix definitions are used. The method is quite compatible with existing implementations of multiple scattering theory and could be readily extended to three-dimensional multiple scattering theory

Simulataneous Formation of InGaN Nanostructures with Varying Shapes for White Light Source Applications

KAUST Repository

Gasim, Anwar A.; Bhattacharya, Pallab K.; Cha, Dong Kyu; Ng, Tien Khee; Ooi, Boon S.

2012-01-01

Varying shapes of InGaN nanostructures were simultaneously formed on silicon epitaxially. The nanowires and nanomushrooms emit violet-blue light, and broad yellow-orange-red luminescence, respectively. The combination of which is promising for white light emission.

TSA waste stream and final waste form composition

International Nuclear Information System (INIS)

Grandy, J.D.; Eddy, T.L.; Anderson, G.L.

1993-01-01

A final vitrified waste form composition, based upon the chemical compositions of the input waste streams, is recommended for the transuranic-contaminated waste stored at the Transuranic Storage Area of the Radioactive Waste Management Complex at the Idaho National Engineering Laboratory. The quantities of waste are large with a considerable uncertainty in the distribution of various waste materials. It is therefore impractical to mix the input waste streams into an ''average'' transuranic-contaminated waste. As a result, waste stream input to a melter could vary widely in composition, with the potential of affecting the composition and properties of the final waste form. This work examines the extent of the variation in the input waste streams, as well as the final waste form under conditions of adding different amounts of soil. Five prominent Rocky Flats Plant 740 waste streams are considered, as well as nonspecial metals and the ''average'' transuranic-contaminated waste streams. The metals waste stream is the most extreme variation and results indicate that if an average of approximately 60 wt% of the mixture is soil, the final waste form will be predominantly silica, alumina, alkaline earth oxides, and iron oxide. This composition will have consistent properties in the final waste form, including high leach resistance, irrespective of the variation in waste stream. For other waste streams, much less or no soil could be required to yield a leach resistant waste form but with varying properties

Constitutive Equation with Varying Parameters for Superplastic Flow Behavior

Science.gov (United States)

Guan, Zhiping; Ren, Mingwen; Jia, Hongjie; Zhao, Po; Ma, Pinkui

2014-03-01

In this study, constitutive equations for superplastic materials with an extra large elongation were investigated through mechanical analysis. From the view of phenomenology, firstly, some traditional empirical constitutive relations were standardized by restricting some strain paths and parameter conditions, and the coefficients in these relations were strictly given new mechanical definitions. Subsequently, a new, general constitutive equation with varying parameters was theoretically deduced based on the general mechanical equation of state. The superplastic tension test data of Zn-5%Al alloy at 340 °C under strain rates, velocities, and loads were employed for building a new constitutive equation and examining its validity. Analysis results indicated that the constitutive equation with varying parameters could characterize superplastic flow behavior in practical superplastic forming with high prediction accuracy and without any restriction of strain path or deformation condition, showing good industrial or scientific interest. On the contrary, those empirical equations have low prediction capabilities due to constant parameters and poor applicability because of the limit of special strain path or parameter conditions based on strict phenomenology.

Modal Vibration Control in Periodic Time-Varying Structures with Focus on Rotor Blade Systems

DEFF Research Database (Denmark)

Christensen, Rene Hardam; Santos, Ilmar

2004-01-01

of active modal controllers. The main aim is to reduce vibrations in periodic time-varying structures. Special emphasis is given to vibration control of coupled bladed rotor systems. A state feedback modal control law is developed based on modal analysis in periodic time-varying structures. The first step...... in the procedure is a transformation of the model into a time-invariant modal form by applying the modal matrices, which are also periodic time-variant. Due to coupled rotor and blade motions complex vibration modes occur in the modal transformed state space model. This implies that the modal transformed model...

Multi-pulse chaotic motions of a rotor-active magnetic bearing system with time-varying stiffness

International Nuclear Information System (INIS)

Zhang, W.; Yao, M.H.; Zhan, X.P.

2006-01-01

In this paper, we investigate the Shilnikov type multi-pulse chaotic dynamics for a rotor-active magnetic bearings (AMB) system with 8-pole legs and the time-varying stiffness. The stiffness in the AMB is considered as the time-varying in a periodic form. The dimensionless equation of motion for the rotor-AMB system with the time-varying stiffness in the horizontal and vertical directions is a two-degree-of-freedom nonlinear system with quadratic and cubic nonlinearities and parametric excitation. The asymptotic perturbation method is used to obtain the averaged equations in the case of primary parametric resonance and 1/2 subharmonic resonance. It is found from the numerical results that there are the phenomena of the Shilnikov type multi-pulse chaotic motions for the rotor-AMB system. A new jumping phenomenon is discovered in the rotor-AMB system with the time-varying stiffness

Λ( t ) cosmology induced by a slowly varying Elko field

Energy Technology Data Exchange (ETDEWEB)

Pereira, S.H.; Pinho, A.S.S.; Silva, J.M. Hoff da [Universidade Estadual Paulista (Unesp), Faculdade de Engenharia, Guaratinguetá, Departamento de Física e Química Av. Dr. Ariberto Pereira da Cunha 333, 12516-410—Guaratinguetá, SP (Brazil); Jesus, J.F., E-mail: shpereira@feg.unesp.br, E-mail: alexandre.pinho510@gmail.com, E-mail: hoff@feg.unesp.br, E-mail: jfjesus@itapeva.unesp.br [Universidade Estadual Paulista (Unesp), Campus Experimental de Itapeva, R. Geraldo Alckmin, 519 Itapeva, SP (Brazil)

2017-01-01

In this work the exact Friedmann-Robertson-Walker equations for an Elko spinor field coupled to gravity in an Einstein-Cartan framework are presented. The torsion functions coupling the Elko field spin-connection to gravity can be exactly solved and the FRW equations for the system assume a relatively simple form. In the limit of a slowly varying Elko spinor field there is a relevant contribution to the field equations acting exactly as a time varying cosmological model Λ( t )=Λ{sub *}+3β H {sup 2}, where Λ{sub *} and β are constants. Observational data using distance luminosity from magnitudes of supernovae constraint the parameters Ω {sub m} and β, which leads to a lower limit to the Elko mass. Such model mimics, then, the effects of a dark energy fluid, here sourced by the Elko spinor field. The density perturbations in the linear regime were also studied in the pseudo-Newtonian formalism.

The Battle of the Bakgatla-Ba-Kgafela Community: Access to and ...

African Journals Online (AJOL)

MJM Venter

2017-11-07

Nov 7, 2017 ... more democratic forms of ownership and governance in general, but ... association; communal land tenure; traditional leadership; Bakgatla-Ba- .... that a dual system prevailed, embodying Western-style national law co-.

A behavioral asset pricing model with a time-varying second moment

International Nuclear Information System (INIS)

Chiarella, Carl; He Xuezhong; Wang, Duo

2006-01-01

We develop a simple behavioral asset pricing model with fundamentalists and chartists in order to study price behavior in financial markets when chartists estimate both conditional mean and variance by using a weighted averaging process. Through a stability, bifurcation, and normal form analysis, the market impact of the weighting process and time-varying second moment are examined. It is found that the fundamental price becomes stable (unstable) when the activities from both types of traders are balanced (unbalanced). When the fundamental price becomes unstable, the weighting process leads to different price dynamics, depending on whether the chartists act as either trend followers or contrarians. It is also found that a time-varying second moment of the chartists does not change the stability of the fundamental price, but it does influence the stability of the bifurcations. The bifurcation becomes stable (unstable) when the chartists are more (less) concerned about the market risk characterized by the time-varying second moment. Different routes to complicated price dynamics are also observed. The analysis provides an analytical foundation for the statistical analysis of the corresponding stochastic version of this type of behavioral model

Holographic cinematography of time-varying reflecting and time-varying phase objects using a Nd:YAG laser

Science.gov (United States)

Decker, A. J.

1982-01-01

The use of a Nd:YAG laser to record holographic motion pictures of time-varying reflecting objects and time-varying phase objects is discussed. Sample frames from both types of holographic motion pictures are presented. The holographic system discussed is intended for three-dimensional flow visualization of the time-varying flows that occur in jet-engine components.

Time-varying BRDFs.

Science.gov (United States)

Sun, Bo; Sunkavalli, Kalyan; Ramamoorthi, Ravi; Belhumeur, Peter N; Nayar, Shree K

2007-01-01

The properties of virtually all real-world materials change with time, causing their bidirectional reflectance distribution functions (BRDFs) to be time varying. However, none of the existing BRDF models and databases take time variation into consideration; they represent the appearance of a material at a single time instance. In this paper, we address the acquisition, analysis, modeling, and rendering of a wide range of time-varying BRDFs (TVBRDFs). We have developed an acquisition system that is capable of sampling a material's BRDF at multiple time instances, with each time sample acquired within 36 sec. We have used this acquisition system to measure the BRDFs of a wide range of time-varying phenomena, which include the drying of various types of paints (watercolor, spray, and oil), the drying of wet rough surfaces (cement, plaster, and fabrics), the accumulation of dusts (household and joint compound) on surfaces, and the melting of materials (chocolate). Analytic BRDF functions are fit to these measurements and the model parameters' variations with time are analyzed. Each category exhibits interesting and sometimes nonintuitive parameter trends. These parameter trends are then used to develop analytic TVBRDF models. The analytic TVBRDF models enable us to apply effects such as paint drying and dust accumulation to arbitrary surfaces and novel materials.

Theoretical analysis of surface stress for a microcantilever with varying widths

International Nuclear Information System (INIS)

Li Xianfang; Peng Xulong

2008-01-01

A theoretical model of surface stress is developed in this paper for a microcantilever with varying widths, and a method for calculating the surface stress via static deflection, slope angle or radius at curvature of the cantilever beam is presented. This model assumes that surface stresses are uniformly distributed on one surface of the cantilever beam. Based on this stressor model and using the small deformation Euler-Bernoulli beam theory, a fourth-order ordinary differential governing equation with varying coefficients or an equivalent second-order integro-differential equation is derived. A simple approach is then proposed to determine the solution of the resulting equation, and a closed-form approximate solution with high accuracy can be obtained. For rectangular and V-shaped microfabricated cantilevers, the dependences of transverse deflection, slope and curvature of the beam on the surface stresses are given explicitly. The obtained results indicate that the zeroth order approximation of the stressor model reduces to the end force model with a linear curvature for a rectangular cantilever. For larger surface stresses, the curvature exhibits a non-linear behaviour. The predictions through the stressor model give higher accuracy than those from the end moment and end force models and satisfactorily agree with experimental data. The derived closed-form solution can serve as a theoretical benchmark for verifying numerically obtained results for microcantilevers as atomic force microscopy and micromechanical sensors

Resonant e+e- production by time-varying electromagnetic field

International Nuclear Information System (INIS)

Farakos, K.; Koutsoumbas, G.; Tiktopoulos, G.

1990-01-01

As pointed out by Cornwall and Tiktopoulos (CT) strong, time-varying electric fields may produce e + e - pairs in a resonant fashion. This effect could be related to the sharp peaks in the e + e - spectrum observed in the GSI heavy-ion collision experiments. We attempt to go beyond the case of spatially uniform fields discussed by CT. We find that resonant e + e - production indeed takes place for electric fields derived from four-potentials of the form A 1 =A 2 =A 0 =0, A 3 =δ(t)b(x 3 ) provided by b(x) has discontinuities with a jump at least equal to π. (orig.)

Lubricant Test Methods for Sheet Metal Forming

DEFF Research Database (Denmark)

Bay, Niels; Olsson, David Dam; Andreasen, Jan Lasson

2008-01-01

appearing in different sheet forming operations such as stretch forming, deep drawing, ironing and punching. The laboratory tests have been especially designed to model the conditions in industrial production. Application of the tests for evaluating new lubricants before introducing them in production has......Sheet metal forming of tribologically difficult materials such as stainless steel, Al-alloys and Ti-alloys or forming in tribologically difficult operations like ironing, punching or deep drawing of thick plate requires often use of environmentally hazardous lubricants such as chlorinated paraffin...... oils in order to avoid galling. The present paper describes a systematic research in the development of new, environmentally harmless lubricants focusing on the lubricant testing aspects. A system of laboratory tests has been developed to study the lubricant performance under the very varied conditions...

Finite-Time H∞ Filtering for Linear Continuous Time-Varying Systems with Uncertain Observations

Directory of Open Access Journals (Sweden)

Huihong Zhao

2012-01-01

Full Text Available This paper is concerned with the finite-time H∞ filtering problem for linear continuous time-varying systems with uncertain observations and ℒ2-norm bounded noise. The design of finite-time H∞ filter is equivalent to the problem that a certain indefinite quadratic form has a minimum and the filter is such that the minimum is positive. The quadratic form is related to a Krein state-space model according to the Krein space linear estimation theory. By using the projection theory in Krein space, the finite-time H∞ filtering problem is solved. A numerical example is given to illustrate the performance of the H∞ filter.

A varying-α brane world cosmology

International Nuclear Information System (INIS)

Youm, Donam

2001-08-01

We study the brane world cosmology in the RS2 model where the electric charge varies with time in the manner described by the varying fine-structure constant theory of Bekenstein. We map such varying electric charge cosmology to the dual variable-speed-of-light cosmology by changing system of units. We comment on cosmological implications for such cosmological models. (author)

Consequences of sibling rivalry vary across life in a passerine bird.

Science.gov (United States)

Bebbington, Kat; Kingma, Sjouke A; Fairfield, Eleanor A; Spurgin, Lewis G; Komdeur, Jan; Richardson, David S

2017-01-01

Many studies have assessed the costs of sibling rivalry in systems where offspring always have competitors, but conclusions about sibling rivalry in these species are restricted to interpreting the cost of changes in the relative level of competition and are often complicated by the expression of potentially costly rivalry related traits. Additionally, the majority of studies focus on early-life sibling rivalry, but the costs of competition can also affect later-life performance. We test a suite of hypothesized immediate (early-life body mass, telomere length, and survival) and delayed (adult reproductive potential and lifespan) costs of sibling rivalry for offspring of differing competitive ability in Seychelles warblers, where most offspring are raised singly and hence competitor success can be compared to a competition-free scenario. Compared to those raised alone, all competing nestlings had lower body mass and weaker competitors experienced reduced survival. However, the stronger competitors appeared to have longer adult breeding tenures and lifespan than those raised alone. We propose that comparisons with competition-free groups, as well as detailed fitness measures across entire lifetimes, are needed to understand the evolution of sibling rivalry and thus individual reproductive strategy in wild systems.

Computational issues of solving the 1D steady gradually varied flow equation

Directory of Open Access Journals (Sweden)

Artichowicz Wojciech

2014-09-01

Full Text Available In this paper a problem of multiple solutions of steady gradually varied flow equation in the form of the ordinary differential energy equation is discussed from the viewpoint of its numerical solution. Using the Lipschitz theorem dealing with the uniqueness of solution of an initial value problem for the ordinary differential equation it was shown that the steady gradually varied flow equation can have more than one solution. This fact implies that the nonlinear algebraic equation approximating the ordinary differential energy equation, which additionally coincides with the wellknown standard step method usually applied for computing of the flow profile, can have variable number of roots. Consequently, more than one alternative solution corresponding to the same initial condition can be provided. Using this property it is possible to compute the water flow profile passing through the critical stage.

Identification of time-varying structural dynamic systems - An artificial intelligence approach

Science.gov (United States)

Glass, B. J.; Hanagud, S.

1992-01-01

An application of the artificial intelligence-derived methodologies of heuristic search and object-oriented programming to the problem of identifying the form of the model and the associated parameters of a time-varying structural dynamic system is presented in this paper. Possible model variations due to changes in boundary conditions or configurations of a structure are organized into a taxonomy of models, and a variant of best-first search is used to identify the model whose simulated response best matches that of the current physical structure. Simulated model responses are verified experimentally. An output-error approach is used in a discontinuous model space, and an equation-error approach is used in the parameter space. The advantages of the AI methods used, compared with conventional programming techniques for implementing knowledge structuring and inheritance, are discussed. Convergence conditions and example problems have been discussed. In the example problem, both the time-varying model and its new parameters have been identified when changes occur.

Comparative waste forms study

International Nuclear Information System (INIS)

Wald, J.W.; Lokken, R.O.; Shade, J.W.; Rusin, J.M.

1980-12-01

A number of alternative process and waste form options exist for the immobilization of nuclear wastes. Although data exists on the characterization of these alternative waste forms, a straightforward comparison of product properties is difficult, due to the lack of standardized testing procedures. The characterization study described in this report involved the application of the same volatility, mechanical strength and leach tests to ten alternative waste forms, to assess product durability. Bulk property, phase analysis and microstructural examination of the simulated products, whose waste loading varied from 5% to 100% was also conducted. The specific waste forms investigated were as follows: Cold Pressed and Sintered PW-9 Calcine; Hot Pressed PW-9 Calcine; Hot Isostatic Pressed PW-9 Calcine; Cold Pressed and Sintered SPC-5B Supercalcine; Hot Isostatic pressed SPC-5B Supercalcine; Sintered PW-9 and 50% Glass Frit; Glass 76-68; Celsian Glass Ceramic; Type II Portland Cement and 10% PW-9 Calcine; and Type II Portland Cement and 10% SPC-5B Supercalcine. Bulk property data were used to calculate and compare the relative quantities of waste form volume produced at a spent fuel processing rate of 5 metric ton uranium/day. This quantity ranged from 3173 L/day (5280 Kg/day) for 10% SPC-5B supercalcine in cement to 83 L/day (294 Kg/day) for 100% calcine. Mechanical strength, volatility, and leach resistance tests provide data related to waste form durability. Glass, glass-ceramic and supercalcine ranked high in waste form durability where as the 100% PW-9 calcine ranked low. All other materials ranked between these two groupings

Linear parameter varying representations for nonlinear control design

Science.gov (United States)

Carter, Lance Huntington

Linear parameter varying (LPV) systems are investigated as a framework for gain-scheduled control design and optimal hybrid control. An LPV system is defined as a linear system whose dynamics depend upon an a priori unknown but measurable exogenous parameter. A gain-scheduled autopilot design is presented for a bank-to-turn (BTT) missile. The method is novel in that the gain-scheduled design does not involve linearizations about operating points. Instead, the missile dynamics are brought to LPV form via a state transformation. This idea is applied to the design of a coupled longitudinal/lateral BTT missile autopilot. The pitch and yaw/roll dynamics are separately transformed to LPV form, where the cross axis states are treated as "exogenous" parameters. These are actually endogenous variables, so such a plant is called "quasi-LPV." Once in quasi-LPV form, a family of robust controllers using mu synthesis is designed for both the pitch and yaw/roll channels, using angle-of-attack and roll rate as the scheduling variables. The closed-loop time response is simulated using the original nonlinear model and also using perturbed aerodynamic coefficients. Modeling and control of engine idle speed is investigated using LPV methods. It is shown how generalized discrete nonlinear systems may be transformed into quasi-LPV form. A discrete nonlinear engine model is developed and expressed in quasi-LPV form with engine speed as the scheduling variable. An example control design is presented using linear quadratic methods. Simulations are shown comparing the LPV based controller performance to that using PID control. LPV representations are also shown to provide a setting for hybrid systems. A hybrid system is characterized by control inputs consisting of both analog signals and discrete actions. A solution is derived for the optimal control of hybrid systems with generalized cost functions. This is shown to be computationally intensive, so a suboptimal strategy is proposed that

Single point incremental forming: Formability of PC sheets

Science.gov (United States)

Formisano, A.; Boccarusso, L.; Carrino, L.; Lambiase, F.; Minutolo, F. Memola Capece

2018-05-01

Recent research on Single Point Incremental Forming of polymers has slightly covered the possibility of expanding the materials capability window of this flexible forming process beyond metals, by demonstrating the workability of thermoplastic polymers at room temperature. Given the different behaviour of polymers compared to metals, different aspects need to be deepened to better understand the behaviour of these materials when incrementally formed. Thus, the aim of the work is to investigate the formability of incrementally formed polycarbonate thin sheets. To this end, an experimental investigation at room temperature was conducted involving formability tests; varying wall angle cone and pyramid frusta were manufactured by processing polycarbonate sheets with different thicknesses and using tools with different diameters, in order to draw conclusions on the formability of polymer sheets through the evaluation of the forming angles and the observation of the failure mechanisms.

The role of periodically varying discharge on river plume structure and transport

Science.gov (United States)

Yuan, Yeping; Horner-Devine, Alexander R.; Avener, Margaret; Bevan, Shaun

2018-04-01

We present results from laboratory experiments that simulate the effects of periodically varying discharge on buoyant coastal plumes. Freshwater is discharged into a two meter diameter tank filled with saltwater on a rotating table. The mean inflow rate, tank rotation period and density of the ambient salt water are varied to simulate a range of inflow Froude and Rossby numbers. The amplitude and the period of the inflow modulation are varied across a range that simulates variability due to tides and storms. Using the optical thickness method, we measure the width and depth of the plume, plume volume and freshwater retention rate in the plume. With constant discharge, freshwater is retained in a growing anticyclonic bulge circulation near the river mouth, as observed in previous studies. When the discharge is varied, the bulge geometry oscillates between a circular plume structure that extends mainly in the offshore direction, and a compressed plume structure that extends mainly in the alongshore direction. The oscillations result in periodic variations in the width and depth of the bulge and the incidence angle formed where the bulge flow re-attaches with the coastal wall. The oscillations are more pronounced for longer modulation periods, but are relatively insensitive to the modulation amplitude. A phase difference between the time varying transport within the bulge and bulge geometry determines the fraction of the bulge flow discharged into the coastal current. As a result, the modulation period determines the variations in amount of freshwater that returns to the bulge. Freshwater retention in the bulge is increased in longer modulation periods and more pronounced for larger modulation amplitudes.

Exponential networked synchronization of master-slave chaotic systems with time-varying communication topologies

International Nuclear Information System (INIS)

Yang Dong-Sheng; Liu Zhen-Wei; Liu Zhao-Bing; Zhao Yan

2012-01-01

The networked synchronization problem of a class of master-slave chaotic systems with time-varying communication topologies is investigated in this paper. Based on algebraic graph theory and matrix theory, a simple linear state feedback controller is designed to synchronize the master chaotic system and the slave chaotic systems with a time-varying communication topology connection. The exponential stability of the closed-loop networked synchronization error system is guaranteed by applying Lyapunov stability theory. The derived novel criteria are in the form of linear matrix inequalities (LMIs), which are easy to examine and tremendously reduce the computation burden from the feedback matrices. This paper provides an alternative networked secure communication scheme which can be extended conveniently. An illustrative example is given to demonstrate the effectiveness of the proposed networked synchronization method. (general)

Numerical and experimental investigation of stretch-flange forming

International Nuclear Information System (INIS)

Cinotti, N.; Shakeri, H.R.; Worswick, M.J.; Truttmann, S.; Finn, M.J.; Jain, M.; Lloyd, D.J.

2000-01-01

Simulations of stretch flange forming operations are undertaken using explicit dynamic finite element calculations incorporating anisotropic yield criteria. Simple circular stretch flanges utilizing a single circular punch to expand the cut-out were considered. Experiments were performed using 101mm diameter tooling on AA 5754 and AA 5182 aluminum alloy sheets, with varying cut-out and gauge size. Metallurgical aspects of the formability of these aluminum alloys and damage mechanisms were studied. Both optical and Scanning Electron Microscopy (SEM) were used to study ductile fracture behaviour in these materials during the forming operation. The limit strains obtained from the circular stretch flange formability experiments are compared to forming limit diagram (FLD) data from hemispherical dome specimens. (author)

Zhang neural network for online solution of time-varying convex quadratic program subject to time-varying linear-equality constraints

International Nuclear Information System (INIS)

Zhang Yunong; Li Zhan

2009-01-01

In this Letter, by following Zhang et al.'s method, a recurrent neural network (termed as Zhang neural network, ZNN) is developed and analyzed for solving online the time-varying convex quadratic-programming problem subject to time-varying linear-equality constraints. Different from conventional gradient-based neural networks (GNN), such a ZNN model makes full use of the time-derivative information of time-varying coefficient. The resultant ZNN model is theoretically proved to have global exponential convergence to the time-varying theoretical optimal solution of the investigated time-varying convex quadratic program. Computer-simulation results further substantiate the effectiveness, efficiency and novelty of such ZNN model and method.

Research on the FDTD method of scattering effects of obliquely incident electromagnetic waves in time-varying plasma sheath on collision and plasma frequencies

Science.gov (United States)

Chen, Wei; Guo, Li-xin; Li, Jiang-ting

2017-04-01

This study analyzes the scattering characteristics of obliquely incident electromagnetic (EM) waves in a time-varying plasma sheath. The finite-difference time-domain algorithm is applied. According to the empirical formula of the collision frequency in a plasma sheath, the plasma frequency, temperature, and pressure are assumed to vary with time in the form of exponential rise. Some scattering problems of EM waves are discussed by calculating the radar cross section (RCS) of the time-varying plasma. The laws of the RCS varying with time are summarized at the L and S wave bands.

Spacetime-varying couplings and Lorentz violation

International Nuclear Information System (INIS)

Kostelecky, V. Alan; Lehnert, Ralf; Perry, Malcolm J.

2003-01-01

Spacetime-varying coupling constants can be associated with violations of local Lorentz invariance and CPT symmetry. An analytical supergravity cosmology with a time-varying fine-structure constant provides an explicit example. Estimates are made for some experimental constraints

Tolerable Time-Varying Overflow on Grass-Covered Slopes

Directory of Open Access Journals (Sweden)

Steven A. Hughes

2015-03-01

Full Text Available Engineers require estimates of tolerable overtopping limits for grass-covered levees, dikes, and embankments that might experience steady overflow. Realistic tolerance estimates can be used for both resilient design and risk assessment. A simple framework is developed for estimating tolerable overtopping on grass-covered slopes caused by slowly-varying (in time overtopping discharge (e.g., events like storm surges or river flood waves. The framework adapts the well-known Hewlett curves of tolerable limiting velocity as a function of overflow duration. It has been hypothesized that the form of the Hewlett curves suggests that the grass erosion process is governed by the flow work on the slope above a critical threshold velocity (referred to as excess work, and the tolerable erosional limit is reached when the cumulative excess work exceeds a given value determined from the time-dependent Hewlett curves. The cumulative excess work is expressed in terms of overflow discharge above a critical discharge that slowly varies in time, similar to a discharge hydrograph. The methodology is easily applied using forecast storm surge hydrographs at specific locations where wave action is minimal. For preliminary planning purposes, when storm surge hydrographs are unavailable, hypothetical equations for the water level and overflow discharge hydrographs are proposed in terms of the values at maximum overflow and the total duration of overflow. An example application is given to illustrate use of the methodology.

Land access and livelihoods in post-conflict Timor-Leste: no magic bullets

Directory of Open Access Journals (Sweden)

Simon P.J. Batterbury

2015-09-01

Full Text Available In Timor-Leste, customary institutions contribute to sustainable and equitable rural development and the establishment of improved access to and management of land, water and other natural resources. Drawing on multi-sited empirical research, we argue that the recognition and valorization of custom and common property management is a prerequisite for sustainable and equitable land tenure reform in Timor-Leste. In a four-community study of the relationship between land access and the practice of rural livelihoods in eastern and western districts of Timor-Leste, where customary management systems are dominant, we found different types of traditional dispute resolution, with deep roots in traditional forms of land management and with varying levels of conflict. The article shows how customary land tenure systems have already managed to create viable moral economies. Interviewees expressed a desire for the government to formalize its recognition and support for customary systems and to provide them with basic livelihood support and services. This was more important than instituting private landholding or state appropriation of community lands, which is perceived to be the focus of national draft land laws and an internationally supported project. We suggest ways in which diverse customary institutions can co-exist and work with state institutions to build collective political legitimacy in the rural hinterlands, within the context of upgrading the quality of rural life, promoting social and ecological harmony, and conflict management.

Shape-forming and densification of ceramic superconductors

International Nuclear Information System (INIS)

Prakash, Om; Thomas, C.A.; Magadum, A.P.; Anklekar, R.M.; Khosla, N.K.; Kumar, Sunil; Chaudhuri, B.; Ramesh, M.; Rao, B.T.; Rama Mohan, T.R.

1991-01-01

Processing studies on varied shape-forming and densification of bulk ceramic superconductor, YBa 2 Cu 3 Osub(7-δ), are reported in this paper. Polyvinyl butyral-polyethylene glycol-trichloroethylene has been found to be the best binder-plasticizer-solvent system in plastic shape-forming. The effect of initial particle morphology on final densification has been the most sensitive single parameter as compared to compaction pressure and final sintering durations at ∼930degC. 1-2-3 powders of mean particle size ∼1.94μm have yielded sintered densities ∼92%T.D. albeit with lower oxygen intake Osub(6.7). (author). 8 refs., 8 figs

Cosmic no-hair theorem with a varying cosmological constant on brane scenario

CERN Document Server

Chakraborty, S

2002-01-01

In this work, we have studied cosmic no-hair theorem for homogeneous anisotropic Bianchi models with a varying cosmological constant (LAMBDA) in Randall-Sundrum braneworld-type scenarios. The matter fields are confined over the 3-brane onto which the five-dimensional Weyl tensor has a non-vanishing projection. The variation of LAMBDA is taken to be the recently proposed form of Vishwakarma and its generalization. In the first case, the universe will isotropize after power-law inflation while there is exponential expansion in the second case.

Effects of feed forms on growth pattern, behavioural responses and ...

African Journals Online (AJOL)

Effects of feed forms on growth pattern, behavioural responses and feacal microbial load ... load and behavioural activities (eating, drinking, physical pen interaction and ... Total organism counts varied significantly (p<0.05) with pigs on T1, T2, ...

TIME-VARYING DYNAMICAL STAR FORMATION RATE

Energy Technology Data Exchange (ETDEWEB)

Lee, Eve J.; Chang, Philip; Murray, Norman, E-mail: evelee@berkeley.edu [Canadian Institute for Theoretical Astrophysics, 60 St. George Street, University of Toronto, Toronto, ON M5S 3H8 (Canada)

2015-02-10

We present numerical evidence of dynamic star formation in which the accreted stellar mass grows superlinearly with time, roughly as t {sup 2}. We perform simulations of star formation in self-gravitating hydrodynamic and magnetohydrodynamic turbulence that is continuously driven. By turning the self-gravity of the gas in the simulations on or off, we demonstrate that self-gravity is the dominant physical effect setting the mass accretion rate at early times before feedback effects take over, contrary to theories of turbulence-regulated star formation. We find that gravitational collapse steepens the density profile around stars, generating the power-law tail on what is otherwise a lognormal density probability distribution function. Furthermore, we find turbulent velocity profiles to flatten inside collapsing regions, altering the size-line width relation. This local flattening reflects enhancements of turbulent velocity on small scales, as verified by changes to the velocity power spectra. Our results indicate that gas self-gravity dynamically alters both density and velocity structures in clouds, giving rise to a time-varying star formation rate. We find that a substantial fraction of the gas that forms stars arrives via low-density flows, as opposed to accreting through high-density filaments.

Mismatch Between the Demands for Tenure and Those of Public Services is Creating a Crossroads in Academic Librarianship. A review of: Johnson, C.M. and E.B. Lindsay. “Why We Do What We Do: Exploring Priorities within Public Services Librarianship.” portal: Libraries and the Academy 6.3 (2006: 347‐69.

Directory of Open Access Journals (Sweden)

David Herron

2007-12-01

Full Text Available Objective – To explore how public services librarians in academic libraries perceive their duties and experience job satisfaction especially in relation to faculty status (tenure track or non‐tenure. Design – A multi‐site study.Setting – Academic libraries in the United States.Subjects – Academic public service librarians.Methods – In March 2004, an online survey containing 25 questions was sent out to 1,510 academic librarians across the UnitedStates. The survey included demographic and professional work‐related questions, but mainly focused on retrieving information about librarian feelings, thoughts, and perceptions in relation to six aspects of the role of the public service librarian, namely: reference, collections, publishing, teaching, committee, and management activities. The survey data was stored in an SQL database and analyzed in various ways to try to see if there were correlations in the replies. In some cases, Chi‐square was used to test for statistical significance.Main results – 328 (22% out of 1,510 potential replies were received. 74% came from public universities and 26% from private institutions. 23% of the respondent librarians had received their MLS before 1980, 34% between 1980 and 1994, and 43% 1995 or later. About 50% had worked as an academic librarian fewer than 10 years and 50% for 10 or more years. About 50% had worked at their current institution five years or fewer and the other 50% for six years ormore. 49% had job descriptions which clearly indicated the relative emphasis of each of the main areas of their job. 50% came from tenure‐track and non‐tenure‐track institutions alike. The librarians were asked to reply to “most” and “least” questions. The following lists show the most chosen responses (in % to the questions.“Most” questions: 80% felt that they were most prepared for reference activities by their library school training.50% felt most satisfied with doing reference

Emergence of synchronization and regularity in firing patterns in time-varying neural hypernetworks

Science.gov (United States)

Rakshit, Sarbendu; Bera, Bidesh K.; Ghosh, Dibakar; Sinha, Sudeshna

2018-05-01

We study synchronization of dynamical systems coupled in time-varying network architectures, composed of two or more network topologies, corresponding to different interaction schemes. As a representative example of this class of time-varying hypernetworks, we consider coupled Hindmarsh-Rose neurons, involving two distinct types of networks, mimicking interactions that occur through the electrical gap junctions and the chemical synapses. Specifically, we consider the connections corresponding to the electrical gap junctions to form a small-world network, while the chemical synaptic interactions form a unidirectional random network. Further, all the connections in the hypernetwork are allowed to change in time, modeling a more realistic neurobiological scenario. We model this time variation by rewiring the links stochastically with a characteristic rewiring frequency f . We find that the coupling strength necessary to achieve complete neuronal synchrony is lower when the links are switched rapidly. Further, the average time required to reach the synchronized state decreases as synaptic coupling strength and/or rewiring frequency increases. To quantify the local stability of complete synchronous state we use the Master Stability Function approach, and for global stability we employ the concept of basin stability. The analytically derived necessary condition for synchrony is in excellent agreement with numerical results. Further we investigate the resilience of the synchronous states with respect to increasing network size, and we find that synchrony can be maintained up to larger network sizes by increasing either synaptic strength or rewiring frequency. Last, we find that time-varying links not only promote complete synchronization, but also have the capacity to change the local dynamics of each single neuron. Specifically, in a window of rewiring frequency and synaptic coupling strength, we observe that the spiking behavior becomes more regular.

Asymptotic theory of time varying networks with burstiness and heterogeneous activation patterns

Science.gov (United States)

Burioni, Raffaella; Ubaldi, Enrico; Vezzani, Alessandro

2017-05-01

The recent availability of large-scale, time-resolved and high quality digital datasets has allowed for a deeper understanding of the structure and properties of many real-world networks. The empirical evidence of a temporal dimension prompted the switch of paradigm from a static representation of networks to a time varying one. In this work we briefly review the framework of time-varying-networks in real world social systems, especially focusing on the activity-driven paradigm. We develop a framework that allows for the encoding of three generative mechanisms that seem to play a central role in the social networks’ evolution: the individual’s propensity to engage in social interactions, its strategy in allocate these interactions among its alters and the burstiness of interactions amongst social actors. The functional forms and probability distributions encoding these mechanisms are typically data driven. A natural question arises if different classes of strategies and burstiness distributions, with different local scale behavior and analogous asymptotics can lead to the same long time and large scale structure of the evolving networks. We consider the problem in its full generality, by investigating and solving the system dynamics in the asymptotic limit, for general classes of ties allocation mechanisms and waiting time probability distributions. We show that the asymptotic network evolution is driven by a few characteristics of these functional forms, that can be extracted from direct measurements on large datasets.

Varying Coefficient Panel Data Model in the Presence of Endogenous Selectivity and Fixed Effects

OpenAIRE

Malikov, Emir; Kumbhakar, Subal C.; Sun, Yiguo

2013-01-01

This paper considers a flexible panel data sample selection model in which (i) the outcome equation is permitted to take a semiparametric, varying coefficient form to capture potential parameter heterogeneity in the relationship of interest, (ii) both the outcome and (parametric) selection equations contain unobserved fixed effects and (iii) selection is generalized to a polychotomous case. We propose a two-stage estimator. Given consistent parameter estimates from the selection equation obta...

The impact of the recent financial crisis on 401(k) account balances.

Science.gov (United States)

VanDerhei, Jack

2009-02-01

401(K) LOSSES FROM THE ECONOMIC CRISIS: During 2008, major U.S. equity indexes were sharply negative, with the S&P 500 Index losing 37.0 percent for the year, which translated into corresponding losses in 401(k) retirement plan assets. But how individual 401(k) participants are affected by the crisis is largely determined by their account balance, age, and job tenure. IMPACT VARIES BY ACCOUNT BALANCE: This Issue Brief estimates changes in average 401(k) balances from Jan. 1, 2008, to Jan. 20, 2009, using the EBRI/ICI 401(k) database of more than 21 million participants. Not surprisingly, how the recent financial market losses affect individual 401(k) account balances is strongly affected by the size of a participant's account balance. Those with low account balances relative to contributions experienced minimal investment losses that were typically more than made up by contributions: Those with less than $10,000 in account balances had an average growth of 40 percent during 2008, since contributions had a bigger impact than investment losses. However, those with more than $200,000 in account balances had an average loss of more than 25 percent. IMPACT VARIES BY AGE AND JOB TENURE: 401(k) participants on the verge of retirement (ages 56-65) had average changes during this period that varied between a positive 1 percent for short-tenure individuals (one to four years with the current employer) to more than a 25 percent loss for those with long tenure (with more than 20 years). SHORT-TERM VS. LONG-TERM: While much of the focus has been on market fluctuations in the last year, investing for retirement security is (or should be) a long-term proposition. When a consistent sample of 2.2 million participants who had been with the same 401(k) plan sponsor for the seven years from 1999-2006 was analyzed, the average estimated growth rates for the period from Jan. 1, 2000 through Jan. 20, 2009, ranged from +29 percent for long-tenure older participants to more than +500

An assessment of burnout in undergraduate athletic training education program directors.

Science.gov (United States)

Walter, Jessica M; Van Lunen, Bonnie L; Walker, Stacy E; Ismaeli, Zahra C; Oñate, James A

2009-01-01

Athletic training education program directors (ATEPDs) often manage their time among students, program administration, and patient care. To assess the level of burnout in ATEPDs and to determine the relationship between burnout and various demographics of ATEPDs. Cross-sectional study. Public and private colleges and universities nationwide. Two hundred forty-nine ATEPDs of undergraduate athletic training education programs accredited by the Commission on Accreditation of Athletic Training Education. We administered the Maslach Burnout Inventory (MBI) to all participants. The MBI consisted of 21 items assessing 3 characteristics of burnout: emotional exhaustion, depersonalization, and personal accomplishment. Another component of the survey requested demographic information about the ATEPDs. We used univariate, multivariate, and factorial analyses of variance with the alpha level set a priori at .05. We also calculated Pearson product moment correlation coefficients. Women had greater emotional exhaustion than men (20.67 +/- 9.43 and 16.47 +/- 9.64, respectively) (P = .001). The difference between tenure-status groups for emotional exhaustion was significant (P = .014), with tenure-track ATEPDs scoring higher on emotional exhaustion than tenured ATEPDs. Pearson product moment correlation coefficients revealed a weak negative relationship among emotional exhaustion and age (r = -0.263, P depersonalization (r = -0.171, P = .007). There was a weak positive relationship between years at current job and personal accomplishment (r = 0.197, P = .002). We found that ATEPDs experienced a moderate form of emotional exhaustion burnout and low depersonalization and personal accomplishment burnout, with women experiencing greater emotional exhaustion than males. Additionally, ATEPDs in tenure-track positions experienced greater emotional exhaustion than tenured ATEPDs. The ATEPDs need to obtain healthy coping strategies early within their directorships to manage components

Special waste-form lysimeters: Arid

International Nuclear Information System (INIS)

Jones, T.L.; Serne, R.J.

1987-08-01

The release of contaminant from solidified low-level waste forms is being studied in a field lysimeter facility at the Hanford Site in southeastern Washington State. Duplicate samples of five different waste forms have been buried in 10 lysimeters since March 1984. Waste-form samples represent three different waste streams and four solidification agents (masonry cement, Portland III cement, Dow polymer /sup (a)/, and bitumen). Most precipitation at the Hanford Site arrives as winter snow; this contributes to a strong seasonal pattern in water storage and drainage observed in the lysimeters. The result is an annual range in the volumetric soil water content from 11% in late winter to 7% in the late summer and early fall, as well as annual changes in pore water velocities from approximately 1 cm/wk in early spring to less than 0.05 cm/wk in early fall. Measurable quantities of tritium and cobalt-60 are being collected in lysimeter drainage water. Approximately 30% of the original tritium inventory has been leached from two lysimeters originally containing tritium. Cobalt-60 is present in all waste forms; it is being collected in the leachate from five lysimeters. The total amount released varies, but in each case it is less than 0.1% of the original cobalt inventory of the waste sample. Nonradioactive constituents contained in the waste form, such as sodium, boron, and sulfate, are also being leached

Distributed Time-Varying Formation Robust Tracking for General Linear Multiagent Systems With Parameter Uncertainties and External Disturbances.

Science.gov (United States)

Hua, Yongzhao; Dong, Xiwang; Li, Qingdong; Ren, Zhang

2017-05-18

This paper investigates the time-varying formation robust tracking problems for high-order linear multiagent systems with a leader of unknown control input in the presence of heterogeneous parameter uncertainties and external disturbances. The followers need to accomplish an expected time-varying formation in the state space and track the state trajectory produced by the leader simultaneously. First, a time-varying formation robust tracking protocol with a totally distributed form is proposed utilizing the neighborhood state information. With the adaptive updating mechanism, neither any global knowledge about the communication topology nor the upper bounds of the parameter uncertainties, external disturbances and leader's unknown input are required in the proposed protocol. Then, in order to determine the control parameters, an algorithm with four steps is presented, where feasible conditions for the followers to accomplish the expected time-varying formation tracking are provided. Furthermore, based on the Lyapunov-like analysis theory, it is proved that the formation tracking error can converge to zero asymptotically. Finally, the effectiveness of the theoretical results is verified by simulation examples.

Should they stay or should they go? Leader duration and financial performance in local health departments.

Science.gov (United States)

Jadhav, Emmanuel D; Holsinger, James W; Mays, Glen; Fardo, David

2015-01-01

The delivery of programs by local health departments (LHDs) has shifted from "if we do not have the money we don't do it" to LHD directors should "identify and fund public health priorities." This shift has subsequently increased performance expectations of LHD leaders. In the for-profit sector the leaders' failure to perform has resulted in a shortening tenure trend. Tenure is a proxy for human capital accumulation. In LHDs, the nature of association, if any, between leader tenure and agency performance is unknown. Examine association between financial performance of LHDs with short-, average-, and long-tenured LHD leaders. Variation in leader characteristics and percent change in expenditure were examined using a longitudinal cohort design and positive deviance methodology. Bivariate analysis of LHD financial performance and leader characteristics was conducted, and a logistic regression model was developed to test association between leader tenure and LHDs that experienced a positive percentage expenditure change. From a total of 2523 LHDs, 1453 were examined. The cross-sectional surveys of US public health agencies conducted by the National Association of County and City Health Officials in 2008 and 2010 contain the leader and LHD variables. Approximately 44% of LHDs experienced a positive percentage expenditure change. Leader tenure, age, gender, and education status were significantly associated with a positive percentage expenditure change using a chi-square test of independence. From the logistic regression analysis tenure, educational status, employment status, area population, governance, classification, and jurisdiction were statistically significant. Local health departments with leaders whose tenure was less than 2 years were less likely than those with average tenure to experience a positive percentage expenditure change. The odds ratios for tenure suggest that tenure is positively associated up to a threshold level and then declines. Implying that

Temporal lobe epilepsy with varying severity: MRI study of 222 patients

International Nuclear Information System (INIS)

Lehericy, S.; Hasboun, D.; Dormont, D.; Marsault, C.; Semah, F.; Baulac, M.; Clemenceau, S.; Granat, O.

1997-01-01

MRI was performed in 222 consecutive adult patients with temporal lobe epilepsy of varying severity from January 1991 to May 1993. The diagnosis of hippocampal sclerosis was established visually by three independent observers. The accuracy of visual assessment of hippocampal asymmetry was compared with volumetric measurements. Neuropathological correlations were obtained in 63 patients with refractory seizures. Temporal lobe abnormalities were observed in 180 patients (81 %) as follows: hippocampal sclerosis in 122 (55 %); developmental abnormalities in 16 (7.2 %); tumours in 15 (6.8 %); scars in 11 (5 %); cavernous angiomas in 10 (4.5 %); miscellaneous lesions in 6. MRI was normal or showed unrelated changes in 42 patients (19 %). Visual assessment correctly lateralised hippocampal sclerosis in 79 of the 84 patients measured (94 %). Temporal lobectomy confirmed the MRI data (side and aetiology) in all 63 operated patients. Patients with normal MRI had an older age of seizure onset and were more often drug-responsive than patients with hippocampal sclerosis. MRI showed temporal lobe abnormalities in 81 % of epileptic patients with varying severity with good neuropathological correlation. Patients with normal MRI had a less severe form of the disease. (orig.)

Influence of Joint Angle on EMG-Torque Model During Constant-Posture, Torque-Varying Contractions.

Science.gov (United States)

Liu, Pu; Liu, Lukai; Clancy, Edward A

2015-11-01

Relating the electromyogram (EMG) to joint torque is useful in various application areas, including prosthesis control, ergonomics and clinical biomechanics. Limited study has related EMG to torque across varied joint angles, particularly when subjects performed force-varying contractions or when optimized modeling methods were utilized. We related the biceps-triceps surface EMG of 22 subjects to elbow torque at six joint angles (spanning 60° to 135°) during constant-posture, torque-varying contractions. Three nonlinear EMG σ -torque models, advanced EMG amplitude (EMG σ ) estimation processors (i.e., whitened, multiple-channel) and the duration of data used to train models were investigated. When EMG-torque models were formed separately for each of the six distinct joint angles, a minimum "gold standard" error of 4.01±1.2% MVC(F90) resulted (i.e., error relative to maximum voluntary contraction at 90° flexion). This model structure, however, did not directly facilitate interpolation across angles. The best model which did so achieved a statistically equivalent error of 4.06±1.2% MVC(F90). Results demonstrated that advanced EMG σ processors lead to improved joint torque estimation as do longer model training durations.

Organizational form, local market structure and corporate social performance in retail

OpenAIRE

Utgård, Jakob

2015-01-01

I study how organizational form and local market structure influence retail firms' corporate social performance (CSP). The theoretical model is based on agency theory, which in its origin focuses on the dyad between the principal and the agent. I extend this perspective and examine how characteristics of the environment outside the dyad influence the outcomes. Retail stores vary in their organizational form and thereby in their incentives to maximize profits. I hypothesize that the different ...

Phase behaviour of oat β-glucan/sodium caseinate mixtures varying in molecular weight.

Science.gov (United States)

Agbenorhevi, Jacob K; Kontogiorgos, Vassilis; Kasapis, Stefan

2013-05-01

The isothermal phase behaviour at 5 °C of mixtures of sodium caseinate and oat β-glucan isolates varying in molecular weight (MW) was investigated by means of phase diagram construction, rheometry, fluorescence microscopy and electrophoresis. Phase diagrams indicated that the compatibility of the β-glucan/sodium caseinate system increases as β-glucan MW decreases. Images of mixtures taken at various biopolymer concentrations revealed phase separated domains. Results also revealed that at the state of thermodynamic equilibrium, lower MW samples yielded considerable viscosity in the mixture. At equivalent hydrodynamic volume of β-glucan in the mixtures, samples varying in molecular weight exhibited similar flow behaviour. A deviation dependent on the protein concentration was observed for the high MW sample in the concentrated regime due to the size of β-glucan aggregates formed. Results demonstrate that by controlling the structural features of β-glucan in mixtures with sodium caseinate, informed manipulation of rheological properties in these systems can be achieved. Copyright © 2012 Elsevier Ltd. All rights reserved.

Alternative Forms of the Rey Auditory Verbal Learning Test: A Review

Directory of Open Access Journals (Sweden)

Keith A. Hawkins

2004-01-01

Full Text Available Practice effects in memory testing complicate the interpretation of score changes over repeated testings, particularly in clinical applications. Consequently, several alternative forms of the Auditory Verbal Learning Test (AVLT have been developed. Studies of these typically indicate that the forms examined are equivalent. However, the implication that the forms in the literature are interchangeable must be tempered by several caveats. Few studies of equivalence have been undertaken; most are restricted to the comparison of single pairs of forms, and the pairings vary across studies. These limitations are exacerbated by the minimal overlapping across studies in variables reported, or in the analyses of equivalence undertaken. The data generated by these studies are nonetheless valuable, as significant practice effects result from serial use of the same form. The available data on alternative AVLT forms are summarized, and recommendations regarding form development and the determination of form equivalence are offered.

HOUSING TENURE Occupied Units by Tenure NMSD 2000

Data.gov (United States)

Earth Data Analysis Center, University of New Mexico — The 2006 Second Edition TIGER/Line files are an extract of selected geographic and cartographic information from the Census TIGER database. The geographic coverage...

Matching Value Propositions with Varied Customer Needs

DEFF Research Database (Denmark)

Heikka, Eija-Liisa; Frandsen, Thomas; Hsuan, Juliana

2018-01-01

Organizations seek to manage varied customer segments using varied value propositions. The ability of a knowledge-intensive business service (KIBS) provider to formulate value propositions into attractive offerings to varied customers becomes a competitive advantage. In this specific business based...... on often highly abstract service offerings, this requires the provider to have a clear overview of its knowledge and resources and how these can be configured to obtain the desired customization of services. Hence, the purpose of this paper is to investigate how a KIBS provider can match value propositions...... with varied customer needs utilizing service modularity. To accomplish this purpose, a qualitative multiple case study is organized around 5 projects allowing within-case and cross-case comparisons. Our findings describe how through the configuration of knowledge and resources a sustainable competitive...

Electrical Programming of Soft Matter: Using Temporally Varying Electrical Inputs To Spatially Control Self Assembly.

Science.gov (United States)

Yan, Kun; Liu, Yi; Zhang, Jitao; Correa, Santiago O; Shang, Wu; Tsai, Cheng-Chieh; Bentley, William E; Shen, Jana; Scarcelli, Giuliano; Raub, Christopher B; Shi, Xiao-Wen; Payne, Gregory F

2018-02-12

The growing importance of hydrogels in translational medicine has stimulated the development of top-down fabrication methods, yet often these methods lack the capabilities to generate the complex matrix architectures observed in biology. Here we show that temporally varying electrical signals can cue a self-assembling polysaccharide to controllably form a hydrogel with complex internal patterns. Evidence from theory and experiment indicate that internal structure emerges through a subtle interplay between the electrical current that triggers self-assembly and the electrical potential (or electric field) that recruits and appears to orient the polysaccharide chains at the growing gel front. These studies demonstrate that short sequences (minutes) of low-power (∼1 V) electrical inputs can provide the program to guide self-assembly that yields hydrogels with stable, complex, and spatially varying structure and properties.

Process and structures for fabrication of solar cells with laser ablation steps to form contact holes

Science.gov (United States)

Harley, Gabriel; Smith, David D; Dennis, Tim; Waldhauer, Ann; Kim, Taeseok; Cousins, Peter John

2013-11-19

Contact holes of solar cells are formed by laser ablation to accomodate various solar cell designs. Use of a laser to form the contact holes is facilitated by replacing films formed on the diffusion regions with a film that has substantially uniform thickness. Contact holes may be formed to deep diffusion regions to increase the laser ablation process margins. The laser configuration may be tailored to form contact holes through dielectric films of varying thickness.

Design of 2D time-varying vector fields.

Science.gov (United States)

Chen, Guoning; Kwatra, Vivek; Wei, Li-Yi; Hansen, Charles D; Zhang, Eugene

2012-10-01

Design of time-varying vector fields, i.e., vector fields that can change over time, has a wide variety of important applications in computer graphics. Existing vector field design techniques do not address time-varying vector fields. In this paper, we present a framework for the design of time-varying vector fields, both for planar domains as well as manifold surfaces. Our system supports the creation and modification of various time-varying vector fields with desired spatial and temporal characteristics through several design metaphors, including streamlines, pathlines, singularity paths, and bifurcations. These design metaphors are integrated into an element-based design to generate the time-varying vector fields via a sequence of basis field summations or spatial constrained optimizations at the sampled times. The key-frame design and field deformation are also introduced to support other user design scenarios. Accordingly, a spatial-temporal constrained optimization and the time-varying transformation are employed to generate the desired fields for these two design scenarios, respectively. We apply the time-varying vector fields generated using our design system to a number of important computer graphics applications that require controllable dynamic effects, such as evolving surface appearance, dynamic scene design, steerable crowd movement, and painterly animation. Many of these are difficult or impossible to achieve via prior simulation-based methods. In these applications, the time-varying vector fields have been applied as either orientation fields or advection fields to control the instantaneous appearance or evolving trajectories of the dynamic effects.

The Design of 3D-Printed Lattice-Reinforced Thickness-Varying Shell Molds for Castings.

Science.gov (United States)

Shangguan, Haolong; Kang, Jinwu; Yi, Jihao; Zhang, Xiaochuan; Wang, Xiang; Wang, Haibin; Huang, Tao

2018-03-30

3D printing technologies have been used gradually for the fabrication of sand molds and cores for castings, even though these molds and cores are dense structures. In this paper, a generation method for lattice-reinforced thickness-varying shell molds is proposed and presented. The first step is the discretization of the STL (Stereo Lithography) model of a casting into finite difference meshes. After this, a shell is formed by surrounding the casting with varying thickness, which is roughly proportional to the surface temperature distribution of the casting that is acquired by virtually cooling it in the environment. A regular lattice is subsequently constructed to support the shell. The outside surface of the shell and lattice in the cubic mesh format is then converted to STL format to serve as the external surface of the new shell mold. The internal surface of the new mold is the casting's surface with the normals of all of the triangles in STL format reversed. Experimental verification was performed on an Al alloy wheel hub casting. Its lattice-reinforced thickness-varying shell mold was generated by the proposed method and fabricated by the binder jetting 3D printing. The poured wheel hub casting was sound and of good surface smoothness. The cooling rate of the wheel hub casting was greatly increased due to the shell mold structure. This lattice-reinforced thickness-varying shell mold generation method is of great significance for mold design for castings to achieve cooling control.

Rotavirus infection in children: mono-and combines forms, especially clinics and course

Directory of Open Access Journals (Sweden)

N. B. Denisyuk

2012-01-01

Full Text Available Analyzed 74 case histories of children under one year with rotavirus infection. The most commonly detected rotavirus gastroenteritis in the form of mono-and combined forms. Mono-infection in 78.3% of cases occurred in the moderate form with a leading syndrome in the form of gastroenteritis, severe dehydration proceeded with symptoms of varying severity. Mixed variants in 98.7% of cases are in the unfavorable premorbid background, in 42.8% of children were registered in the severe forms, and children younger than 6 months were erased within. The diagnosis of intestinal infection was confirmed by PCR, bacteriological and immunological methods.

Nematode consumption by mite communities varies in different forest microhabitats as indicated by molecular gut content analysis.

Science.gov (United States)

Heidemann, Kerstin; Ruess, Liliane; Scheu, Stefan; Maraun, Mark

2014-01-01

Soil animals live in complex and heterogeneous habitats including litter of various types but also microhabitats such as mosses, fungal mats and grass patches. Soil food webs have been separated into a slow fungal and a fast bacterial energy channel. Bacterial-feeding nematodes are an important component of the bacterial energy channel by consuming bacteria and forming prey for higher trophic levels such as soil microarthropods. Investigating the role of nematodes as prey for higher trophic level consumers has been hampered by methodological problems related to their small body size and lack in skeletal structures which can be traced in the gut of consumers. Recent studies using molecular gut content analyses suggest that nematodes form major prey of soil microarthropods including those previously assumed to live as detritivores. Using molecular markers we traced nematode prey in fourteen abundant soil microarthropod taxa of Mesostigmata and Oribatida (both Acari) from three different microhabitats (litter, grass and moss). Consumption of nematodes varied between mite species indicating that trophic niche variation contributes to the high diversity of microarthropods in deciduous forests. Further, consumption of nematodes by Mesostigmata (but not Oribatida) differed between microhabitats indicating that trophic niches vary with habitat characteristics. Overall, the results suggest that free-living bacterial-feeding nematodes form important prey for soil microarthropods including those previously assumed to live as detritivores.

Relevance of First-Tier, Peer-Reviewed Journals in the Tenure and Promotion Process at Non-Doctoral Granting Engineering Institutions

Directory of Open Access Journals (Sweden)

Amanda S. Florio

2012-02-01

Full Text Available The IEEE (formerly the Institute of Electrical and Electronics Engineers is the world's largest professional society dedicated to the advancement of technology. While it is indeed growing into multiple technology areas, the IEEE is still first an organization of electrical, electronics, and computer engineering professionals. It has over 400,000 members and publishes nearly 100, first-tier, peer-reviewed journals. As such a large purveyor of scholarly works, engineering faculty at almost all academic institutions (doctoral granting and non-doctoral granting are familiar with the IEEE. For this reason, the IEEE makes an excellent case study for the relevance of first-tier, peer-reviewed journals in the tenure and promotion process at non-doctoral granting engineering institutions. In our work, we surveyed editors of the 97 IEEE journals. 93% of respondents indicated that 10% or less of their submissions were from non-academic institutions. None (0% of the respondents believed that the number of non-doctoral granting institution submissions would be increasing over the next three years. In fact, a majority of the respondents (55% see the number of non-doctoral granting institution submissions decreasing in the same time frame. To correlate this data, we examined a sample of 2,099 articles published in the first issue of each IEEE journal in 2009. 357 (17% of these 2,099 articles were authored by individuals from academic institutions in the United States. Of the 357, only 35 were published by individuals from non-doctoral granting institutions (1.7%, with only 8 (0.38% from institutions where a bachelor degree is the highest offered.

Analysis of Urban Households' Preference for Informal Access to ...

African Journals Online (AJOL)

2016-10-02

Oct 2, 2016 ... Keywords: Urban Households, Informal Access, Residential Land, Insecure Tenure Factors. Introduction. Informal ..... its complex system. In Minna, this central control has led to certain ill-practices by land officials who accords some form of preferential treatment to some applicants. This act on one hand is ...

Literatura chicana: Vida en busca de forma (Chicano Literature: Life in Search of Form).

Science.gov (United States)

Rivera, Tomas

The Chicano culture is searching for appropriate expression in art forms and literature. The Chicano novel and essay, often written in English, seem directed toward the North American public. The short story is the most varied in viewpoint and most versatile in form. Poetry captures the Chicano sensitivity. It is almost impossible to note the…

Prediction and control of pillow defect in single point incremental forming using numerical simulations

International Nuclear Information System (INIS)

Isidore, B. B. Lemopi; Hussain, G.; Khan, Wasim A.; Shamachi, S. Pourhassan

2016-01-01

Pillows formed at the center of sheets in Single point incremental forming (SPIF) are fabrication defects which adversely affect the geometrical accuracy and formability of manufactured parts. This study is focused on using FEA as a tool to predict and control pillowing in SPIF by varying tool size and shape. 3D Finite element analysis (FEA) and experiments are carried out using annealed Aluminum 1050. From FEA, it is found out that the stress/strain state in the immediate vicinity of the forming tool in the transverse direction plays a determinant role on sheet pillowing. Furthermore, pillow height increases as compression in the sheet-plane increases. The nature of in-plane stresses in the transverse direction varies from compressive to tensile as the tool-end geometry is changed from spherical to flat. Additionally, the magnitude of corresponding in-plane stresses decreases as the tool radius increases. According to measurements from the FEA model, flat end tools and large radii both retard pillow formation. However, the influence of changing tool end shape from hemispherical to flat is observed to be more important than the effect of varying tool radius, because the deformation zone remains in tension in the transverse direction while forming with flat end tools. These findings are verified by conducting a set of experiments. A fair agreement between the FEM and empirical results show that FEM can be employed as a tool to predict and control the pillow defect in SPIF.

Prediction and control of pillow defect in single point incremental forming using numerical simulations

Energy Technology Data Exchange (ETDEWEB)

Isidore, B. B. Lemopi [Eastern Mediterranean University, Gazimagusa (Turkmenistan); Hussain, G.; Khan, Wasim A. [GIK Institute of Engineering, Swabi (Pakistan); Shamachi, S. Pourhassan [University of Minho, Guimaraes (Portugal)

2016-05-15

Pillows formed at the center of sheets in Single point incremental forming (SPIF) are fabrication defects which adversely affect the geometrical accuracy and formability of manufactured parts. This study is focused on using FEA as a tool to predict and control pillowing in SPIF by varying tool size and shape. 3D Finite element analysis (FEA) and experiments are carried out using annealed Aluminum 1050. From FEA, it is found out that the stress/strain state in the immediate vicinity of the forming tool in the transverse direction plays a determinant role on sheet pillowing. Furthermore, pillow height increases as compression in the sheet-plane increases. The nature of in-plane stresses in the transverse direction varies from compressive to tensile as the tool-end geometry is changed from spherical to flat. Additionally, the magnitude of corresponding in-plane stresses decreases as the tool radius increases. According to measurements from the FEA model, flat end tools and large radii both retard pillow formation. However, the influence of changing tool end shape from hemispherical to flat is observed to be more important than the effect of varying tool radius, because the deformation zone remains in tension in the transverse direction while forming with flat end tools. These findings are verified by conducting a set of experiments. A fair agreement between the FEM and empirical results show that FEM can be employed as a tool to predict and control the pillow defect in SPIF.

Design of 2D Time-Varying Vector Fields

KAUST Repository

Chen, Guoning

2012-10-01

Design of time-varying vector fields, i.e., vector fields that can change over time, has a wide variety of important applications in computer graphics. Existing vector field design techniques do not address time-varying vector fields. In this paper, we present a framework for the design of time-varying vector fields, both for planar domains as well as manifold surfaces. Our system supports the creation and modification of various time-varying vector fields with desired spatial and temporal characteristics through several design metaphors, including streamlines, pathlines, singularity paths, and bifurcations. These design metaphors are integrated into an element-based design to generate the time-varying vector fields via a sequence of basis field summations or spatial constrained optimizations at the sampled times. The key-frame design and field deformation are also introduced to support other user design scenarios. Accordingly, a spatial-temporal constrained optimization and the time-varying transformation are employed to generate the desired fields for these two design scenarios, respectively. We apply the time-varying vector fields generated using our design system to a number of important computer graphics applications that require controllable dynamic effects, such as evolving surface appearance, dynamic scene design, steerable crowd movement, and painterly animation. Many of these are difficult or impossible to achieve via prior simulation-based methods. In these applications, the time-varying vector fields have been applied as either orientation fields or advection fields to control the instantaneous appearance or evolving trajectories of the dynamic effects. © 1995-2012 IEEE.

Design of 2D Time-Varying Vector Fields

KAUST Repository

Chen, Guoning; Kwatra, Vivek; Wei, Li-Yi; Hansen, Charles D.; Zhang, Eugene

2012-01-01

Design of time-varying vector fields, i.e., vector fields that can change over time, has a wide variety of important applications in computer graphics. Existing vector field design techniques do not address time-varying vector fields. In this paper, we present a framework for the design of time-varying vector fields, both for planar domains as well as manifold surfaces. Our system supports the creation and modification of various time-varying vector fields with desired spatial and temporal characteristics through several design metaphors, including streamlines, pathlines, singularity paths, and bifurcations. These design metaphors are integrated into an element-based design to generate the time-varying vector fields via a sequence of basis field summations or spatial constrained optimizations at the sampled times. The key-frame design and field deformation are also introduced to support other user design scenarios. Accordingly, a spatial-temporal constrained optimization and the time-varying transformation are employed to generate the desired fields for these two design scenarios, respectively. We apply the time-varying vector fields generated using our design system to a number of important computer graphics applications that require controllable dynamic effects, such as evolving surface appearance, dynamic scene design, steerable crowd movement, and painterly animation. Many of these are difficult or impossible to achieve via prior simulation-based methods. In these applications, the time-varying vector fields have been applied as either orientation fields or advection fields to control the instantaneous appearance or evolving trajectories of the dynamic effects. © 1995-2012 IEEE.

Development of a procedure for forming assisted thermal joining of tubes

Science.gov (United States)

Chen, Hui; Löbbe, Christian; Staupendahl, Daniel; Tekkaya, A. Erman

2018-05-01

With the demand of lightweight design in the automotive industry, not only the wall-thicknesses of tubular components of the chassis or spaceframe are continuously decreased. Also the thicknesses of exhaust system parts are reduced to save material and mass. However, thinner tubular parts bring about additional challenges in joining. Welding or brazing methods, which are utilized in joining tubes with specific requirements concerning leak tightness, are sensitive to the gap between the joining partners. Furthermore, a large joining area is required to ensure the durability of the joint. The introduction of a forming step in the assembled state prior to thermal joining can define and control the gap for subsequent brazing or welding. The mechanical pre-joint resulting from the previously described calibration step also results in easier handling of the tubes prior to thermal joining. In the presented investigation, a spinning process is utilized to produce force-fit joints of varying lengths and diameter reduction and form-fit joints with varying geometrical attributes. The spinning process facilitates a high formability and geometrical flexibility, while at the achievable precision is high and the process forces are low. The strength of the joints is used to evaluate the joint quality. Finally, a comparison between joints produced by forming with subsequent brazing and original tube is conducted, which presents the high performance of the developed procedure for forming assisted thermal joining.

Morphological Evolution of Gyroid-Forming Block Copolymer Thin Films with Varying Solvent Evaporation Rate.

Science.gov (United States)

Wu, Yi-Hsiu; Lo, Ting-Ya; She, Ming-Shiuan; Ho, Rong-Ming

2015-08-05

In this study, we aim to examine the morphological evolution of block copolymer (BCP) nanostructured thin films through solvent evaporation at different rates for solvent swollen polystyrene-block-poly(l-lactide) (PS-PLLA). Interesting phase transitions from disorder to perpendicular cylinder and then gyroid can be found while using a partially selective solvent for PS to swell PS-PLLA thin film followed by solvent evaporation. During the transitions, gyroid-forming BCP thin film with characteristic crystallographic planes of (111)G, (110)G, and (211)G parallel to air surface can be observed, and will gradually transform into coexisting (110)G and (211)G planes, and finally transforms to (211)G plane due to the preferential segregation of constituted block to the surface (i.e., the thermodynamic origin for self-assembly) that affects the relative amount of each component at the air surface. With the decrease on the evaporation rate, the disorder phase will transform to parallel cylinder and then directly to (211)G without transition to perpendicular cylinder phase. Most importantly, the morphological evolution of PS-PLLA thin films is strongly dependent upon the solvent removal rate only in the initial stage of the evaporation process due to the anisotropy of cylinder structure. Once the morphology is transformed back to the isotropic gyroid structure after long evaporation, the morphological evolution will only relate to the variation of the surface composition. Similar phase transitions at the substrate can also be obtained by controlling the ratio of PLLA-OH to PS-OH homopolymers to functionalize the substrate. As a result, the fabrication of well-defined nanostructured thin films with controlled orientation can be achieved by simple swelling and deswelling with controlled evaporation rate.

A System of Test Methods for Sheet Metal Forming Tribology

DEFF Research Database (Denmark)

Bay, Niels; Olsson, David Dam; Andreasen, Jan Lasson

2007-01-01

Sheet metal forming of tribologically difficult materials such as stainless steel, Al-alloys and Ti-alloys or forming in tribologically difficult operations like ironing, punching or deep drawing of thick plate requires often use of environmentally hazardous lubricants such as chlorinated paraffin...... oils in order to avoid galling. The present paper describes a systematic research in the development of new, environmentally harmless lubricants focusing on the lubricant testing aspects. A system of laboratory tests has been developed to study the lubricant performance under the very varied conditions...... appearing in different sheet forming operations such as stamping, deep drawing, ironing and punching. The laboratory tests have been especially designed to model the conditions in industrial production....

Time-varying Crash Risk

DEFF Research Database (Denmark)

Christoffersen, Peter; Feunoua, Bruno; Jeon, Yoontae

We estimate a continuous-time model with stochastic volatility and dynamic crash probability for the S&P 500 index and find that market illiquidity dominates other factors in explaining the stock market crash risk. While the crash probability is time-varying, its dynamic depends only weakly on re...

Time varying voltage combustion control and diagnostics sensor

Science.gov (United States)

Chorpening, Benjamin T [Morgantown, WV; Thornton, Jimmy D [Morgantown, WV; Huckaby, E David [Morgantown, WV; Fincham, William [Fairmont, WV

2011-04-19

A time-varying voltage is applied to an electrode, or a pair of electrodes, of a sensor installed in a fuel nozzle disposed adjacent the combustion zone of a continuous combustion system, such as of the gas turbine engine type. The time-varying voltage induces a time-varying current in the flame which is measured and used to determine flame capacitance using AC electrical circuit analysis. Flame capacitance is used to accurately determine the position of the flame from the sensor and the fuel/air ratio. The fuel and/or air flow rate (s) is/are then adjusted to provide reduced flame instability problems such as flashback, combustion dynamics and lean blowout, as well as reduced emissions. The time-varying voltage may be an alternating voltage and the time-varying current may be an alternating current.

Perceptions of Deviant Behaviour in the Workplace

Directory of Open Access Journals (Sweden)

Daniela de Carvalho Wilks

2012-01-01

Full Text Available Employee misconduct in the workplace is relatively common and may be counterproductivein social and material terms. To identify which undesirable behavioursare considered acceptable is the first step to develop ways to reducedeviance in organizational settings. The purpose of this study was to examinethe perceived acceptability of deviant behaviour in the workplace, and to analysethe relation between the degree of such acceptance with organizationalcommitment, job satisfaction, and organizational tenure. Data was obtainedfrom 223 adults employed full-time. Results suggest a positive relationshipbetween the degree of acceptability of certain forms of deviant behaviour andorganizational commitment, but not with job satisfaction. They further indicatethat tenure was the factor having the most impact on the acceptanceof deviant behaviours. Implications of the findings for the management arediscussed.

Detection of dynamically varying interaural time differences

DEFF Research Database (Denmark)

Kohlrausch, Armin; Le Goff, Nicolas; Breebaart, Jeroen

2010-01-01

of fringes surrounding the probe is equal to the addition of the effects of the individual fringes. In this contribution, we present behavioral data for the same experimental condition, called dynamically varying ITD detection, but for a wider range of probe and fringe durations. Probe durations varied...

Energy demand with the flexible double-logarithmic functional form

International Nuclear Information System (INIS)

Nan, G.D.; Murry, D.A.

1992-01-01

A flexible double-logarithmic function form is developed to meet assumptions of consumer behavior. Then annual residential and commercial data (1970-87) are applied to this functional form to examine demand for petroleum products, electricity, and natural gas in California. The traditional double log-linear functional form has shortcomings of constant elasticities. The regression equations in this study, with varied estimated elasticities, overcome some of these shortcomings. All short-run own-price elasticities are inelastic and all income elasticities are close to unity in this study. According to the short-run time-trend elasticities, consumers' fuel preference in California is electricity. The long-run income elasticities also indicate that the residential consumers will consume more electricity and natural gas as their energy budgets increase in the long run. 14 refs., 5 tabs

On the material properties of shell plate formed by line heating

Directory of Open Access Journals (Sweden)

Hyung Kyun Lim

2017-01-01

Full Text Available This paper is concerned with investigating the plastic material properties of steel plate formed by line heating method, and is aimed at implementing more rational design considering the accidental limit states such as collision or grounding. For the present study, line heating test for marine grade steel plate has been carried out with varying plate thickness and heating speed, and then microscopic examination and tensile test have been carried out. From the microscopic, it is found that the grain refined zones like ferrite and pearlite are formed all around the heat affected zone. From the tensile test results, it is seen that yield strength, tensile strength, fracture strain, hardening exponent and strength coefficient vary with plate thickness and heat input quantity. The formulae relating the material properties and heat input parameter should be, therefore, derived for the design purpose considering the accidental impact loading. This paper ends with describing the extension of the present study.

Estimating varying coefficients for partial differential equation models.

Science.gov (United States)

Zhang, Xinyu; Cao, Jiguo; Carroll, Raymond J

2017-09-01

Partial differential equations (PDEs) are used to model complex dynamical systems in multiple dimensions, and their parameters often have important scientific interpretations. In some applications, PDE parameters are not constant but can change depending on the values of covariates, a feature that we call varying coefficients. We propose a parameter cascading method to estimate varying coefficients in PDE models from noisy data. Our estimates of the varying coefficients are shown to be consistent and asymptotically normally distributed. The performance of our method is evaluated by a simulation study and by an empirical study estimating three varying coefficients in a PDE model arising from LIDAR data. © 2017, The International Biometric Society.

Planting the Seeds of a New Agriculture: Living with the Land in Central America.

Science.gov (United States)

Adriance, Jim

1995-01-01

Central America's macroeconomics, land tenure patterns, and population growth are forcing small-scale farmers to alternatives based on farmer-to-farmer teaching and farming in concert with the environment. Discusses major schools of thought that have fueled this phenomenon, and how extension services and isolated groups are joining to form a…

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African Journals Online (AJOL)

PUBLICATIONS1

assemblies to include the preservation of farmlands in the management of ... to urban development in the form of compensation and provision of ... What has happened to tenure security for the ... involved a 'drink' presented by the title recipi- ... land, the consideration of land as a 'social ...... problems in Southern Africa.

A New Tool for Identifying Research Standards and Evaluating Research Performance

Science.gov (United States)

Bacon, Donald R.; Paul, Pallab; Stewart, Kim A.; Mukhopadhyay, Kausiki

2012-01-01

Much has been written about the evaluation of faculty research productivity in promotion and tenure decisions, including many articles that seek to determine the rank of various marketing journals. Yet how faculty evaluators combine journal quality, quantity, and author contribution to form judgments of a scholar's performance is unclear. A…

New varying speed of light theories

CERN Document Server

Magueijo, J

2003-01-01

We review recent work on the possibility of a varying speed of light (VSL). We start by discussing the physical meaning of a varying $c$, dispelling the myth that the constancy of $c$ is a matter of logical consistency. We then summarize the main VSL mechanisms proposed so far: hard breaking of Lorentz invariance; bimetric theories (where the speeds of gravity and light are not the same); locally Lorentz invariant VSL theories; theories exhibiting a color dependent speed of light; varying $c$ induced by extra dimensions (e.g. in the brane-world scenario); and field theories where VSL results from vacuum polarization or CPT violation. We show how VSL scenarios may solve the cosmological problems usually tackled by inflation, and also how they may produce a scale-invariant spectrum of Gaussian fluctuations, capable of explaining the WMAP data. We then review the connection between VSL and theories of quantum gravity, showing how ``doubly special'' relativity has emerged as a VSL effective model of quantum space...

The Design of 3D-Printed Lattice-Reinforced Thickness-Varying Shell Molds for Castings

Science.gov (United States)

Shangguan, Haolong; Kang, Jinwu; Yi, Jihao; Zhang, Xiaochuan; Wang, Xiang; Wang, Haibin; Huang, Tao

2018-01-01

3D printing technologies have been used gradually for the fabrication of sand molds and cores for castings, even though these molds and cores are dense structures. In this paper, a generation method for lattice-reinforced thickness-varying shell molds is proposed and presented. The first step is the discretization of the STL (Stereo Lithography) model of a casting into finite difference meshes. After this, a shell is formed by surrounding the casting with varying thickness, which is roughly proportional to the surface temperature distribution of the casting that is acquired by virtually cooling it in the environment. A regular lattice is subsequently constructed to support the shell. The outside surface of the shell and lattice in the cubic mesh format is then converted to STL format to serve as the external surface of the new shell mold. The internal surface of the new mold is the casting’s surface with the normals of all of the triangles in STL format reversed. Experimental verification was performed on an Al alloy wheel hub casting. Its lattice-reinforced thickness-varying shell mold was generated by the proposed method and fabricated by the binder jetting 3D printing. The poured wheel hub casting was sound and of good surface smoothness. The cooling rate of the wheel hub casting was greatly increased due to the shell mold structure. This lattice-reinforced thickness-varying shell mold generation method is of great significance for mold design for castings to achieve cooling control. PMID:29601543

The Design of 3D-Printed Lattice-Reinforced Thickness-Varying Shell Molds for Castings

Directory of Open Access Journals (Sweden)

Haolong Shangguan

2018-03-01

Full Text Available 3D printing technologies have been used gradually for the fabrication of sand molds and cores for castings, even though these molds and cores are dense structures. In this paper, a generation method for lattice-reinforced thickness-varying shell molds is proposed and presented. The first step is the discretization of the STL (Stereo Lithography model of a casting into finite difference meshes. After this, a shell is formed by surrounding the casting with varying thickness, which is roughly proportional to the surface temperature distribution of the casting that is acquired by virtually cooling it in the environment. A regular lattice is subsequently constructed to support the shell. The outside surface of the shell and lattice in the cubic mesh format is then converted to STL format to serve as the external surface of the new shell mold. The internal surface of the new mold is the casting’s surface with the normals of all of the triangles in STL format reversed. Experimental verification was performed on an Al alloy wheel hub casting. Its lattice-reinforced thickness-varying shell mold was generated by the proposed method and fabricated by the binder jetting 3D printing. The poured wheel hub casting was sound and of good surface smoothness. The cooling rate of the wheel hub casting was greatly increased due to the shell mold structure. This lattice-reinforced thickness-varying shell mold generation method is of great significance for mold design for castings to achieve cooling control.

The Effect of Length in Employment Sites’ Web Form Design on User Preferences

Directory of Open Access Journals (Sweden)

Yu-Ching Wang

2014-06-01

Full Text Available Web form has become a critical component for many Web applications and services. Previous research has investigated into the general design of web form layout without examining the impact of variations in format, length and structure on user experience. This study explores users’ preference and performance over Web forms of different lengths deployed on an employment site. Three types of design of Web forms were developed as the experiment instruments for 48 participants to test and evaluate. Results show that participants’ preferences and satisfaction varied by the length of Web forms. Participants’ preferences were also affected by their previous Internet experiences with job websites. In the end, recommendations for design principles for Web forms used for job sites were presented. [Article content in Chinese

Microstructures and mechanical properties of age-formed 7050 aluminum alloy

International Nuclear Information System (INIS)

Chen, J.F.; Zhen, L.; Jiang, J.T.; Yang, L.; Shao, W.Z.; Zhang, B.Y.

2012-01-01

Highlights: ► Age-forming leads to the grain elongation in 7050 alloy. ► Age-forming varies the texture components in 7050 alloy. ► Age-forming promotes precipitates growth and PFZ enlargement in 7050 alloy. ► Age-forming induces to descend apparently elongation in 7050 alloy. ► The effect of age-forming on microstructure and properties is discussed in-depth. - Abstract: The effects of age-forming on microstructures and mechanical properties of 7050 Al alloy were investigated in this work. The alloy was subjected to age-forming as well as stress-free ageing at 160 °C for 6, 12, 18 and 24 h, and its microstructures were characterized by electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). It was shown that creep might lead to grain elongation during age-forming, and the applied stress induces the coarsening of precipitates in 7050 Al alloy. The texture in the alloy was also influenced by age-forming. Consequently, the differences in microstructures result in differences in mechanical properties of age-forming versus traditional stress-free ageing. The ultimate tensile strength of age-formed samples were slightly lower than that of stress-free aged samples, while the yield strength of age-formed samples were apparently lower than that of stress-free aged samples. Specifically, the elongation of samples age-formed displays apparently decrease.

Teaching Form as Form

DEFF Research Database (Denmark)

Keiding, Tina Bering

2012-01-01

understanding of form per se, or, to use an expression from this text, of form as form. This challenge can be reduced to one question: how can design teaching support students in achieving not only the ability to recognize and describe different form-related concepts in existing design (i.e. analytical...

How Are You Doing? The Elements of Effective Performance Management

Science.gov (United States)

Kelley, Jessica

2012-01-01

Whether an employee is a top performer or at risk of dismissal, clear and consistent feedback plays a key role in his or her professional development. Informal and formal feedback are crucial throughout an employee's tenure. Through the use of formal performance evaluation forms and regular performance discussion meetings, employees and managers…

Learning lessons from traditional leaders in Ghana | IDRC ...

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

2011-02-08

Feb 8, 2011 ... Now a professor in the Department of Political Science at the ... on major policy questions such as land tenure, gender issues, and health. ... leaders into democratic forms of government, in several others — mostly those who ... (See box for more on traditional leaders' involvement in the fight against AIDS.).

to view fulltext PDF

Indian Academy of Sciences (India)

Michael Faraday, who had little schooling but excellent education during his tenure as assistant to the famous Humphry Davy, went on to become one of the most effective proponents of science: His masterly exposi tion of the subjects he spoke on and the well thought out experiments that supported them formed the ...

The effect of juvenile hormone on Polistes wasp fertility varies with cooperative behavior.

Science.gov (United States)

Tibbetts, Elizabeth A; Sheehan, Michael J

2012-04-01

Social insects provide good models for studying how and why the mechanisms that underlie reproduction vary, as there is dramatic reproductive plasticity within and between species. Here, we test how the effect of juvenile hormone (JH) on fertility covaries with cooperative behavior in workers and nest-founding queens in the primitively eusocial wasp Polistes metricus. P. metricus foundresses and workers appear morphologically similar and both are capable of reproduction, though there is variation in the extent of social cooperation and the probability of reproduction across castes. Do the endocrine mechanisms that mediate reproduction co-vary with cooperative behavior? We found dramatic differences in the effect of JH on fertility across castes. In non-cooperative nest-founding queens, all individuals responded to JH by increasing their fertility. However, in cooperative workers, the effect of JH on fertility varies with body weight; large workers increase their fertility in response to JH while small workers do not. The variation in JH response may be an adaptation to facilitate resource allocation based on the probability of independent reproduction. This work contrasts with previous studies in closely related Polistes dominulus paper wasps, in which both foundresses and workers form cooperative associations and both castes show similar, condition-dependent JH response. The variation in JH responsiveness within and between species suggests that endocrine responsiveness and the factors influencing caste differentiation are surprisingly evolutionarily labile. Copyright © 2012 Elsevier Inc. All rights reserved.

NRC/AMRMC Resident Research Associateship Program

Science.gov (United States)

2016-04-27

stem-cell released molecule as a therapy in blast-injured retina Miller, Christine 2/4/2013-2/3/2016 1 Optimized protocol to isolate, identify, and...derived self-formed optic cups in laser-injured retina 7) SUMMARY OF RESEARCH DURING TENURE Itemize significant findings in concise form, utilizing key...during retinogenesis 5) Formulate a research plan on using stem-cell released molecule as a therapy in blast-injured retina (USMA Davies Fellow: please

Alternatives for high-level waste forms, containers, and container processing systems

International Nuclear Information System (INIS)

Crawford, T.W.

1995-01-01

This study evaluates alternatives for high-level waste forms, containers, container processing systems, and onsite interim storage. Glass waste forms considered are cullet, marbles, gems, and monolithic glass. Small and large containers configured with several combinations of overpack confinement and shield casks are evaluated for these waste forms. Onsite interim storage concepts including canister storage building, bore holes, and storage pad were configured with various glass forms and canister alternatives. All favorable options include the monolithic glass production process as the waste form. Of the favorable options the unshielded 4- and 7-canister overpack options have the greatest technical assurance associated with their design concepts due to their process packaging and storage methods. These canisters are 0.68 m and 0.54 m in diameter respectively and 4.57 m tall. Life-cycle costs are not a discriminating factor in most cases, varying typically less than 15 percent

New Passivity Criteria for Fuzzy Bam Neural Networks with Markovian Jumping Parameters and Time-Varying Delays

Science.gov (United States)

Vadivel, P.; Sakthivel, R.; Mathiyalagan, K.; Thangaraj, P.

2013-02-01

This paper addresses the problem of passivity analysis issue for a class of fuzzy bidirectional associative memory (BAM) neural networks with Markovian jumping parameters and time varying delays. A set of sufficient conditions for the passiveness of the considered fuzzy BAM neural network model is derived in terms of linear matrix inequalities by using the delay fractioning technique together with the Lyapunov function approach. In addition, the uncertainties are inevitable in neural networks because of the existence of modeling errors and external disturbance. Further, this result is extended to study the robust passivity criteria for uncertain fuzzy BAM neural networks with time varying delays and uncertainties. These criteria are expressed in the form of linear matrix inequalities (LMIs), which can be efficiently solved via standard numerical software. Two numerical examples are provided to demonstrate the effectiveness of the obtained results.

Processes for forming exoergic structures with the use of a plasma and for producing dense refractory bodies of arbitrary shape therefrom

International Nuclear Information System (INIS)

Holt, J.B.; Kelly, M.D.

1990-01-01

Plasma spraying methods of forming exoergic structures and coatings, as well as exoergic structures produced by such methods, are presented. The methods include the plasma spraying of reactive exoergic materials that are capable of sustaining a combustion synthesis reaction onto a flat substrate or into molds of arbitrary shape and igniting the plasma sprayed materials, either under an inert gas pressure or not, to form refractory materials of varying densities and of varying shapes

Velocity form of the Kohn-Sham frequency-dependent polarizability equations

International Nuclear Information System (INIS)

Bartolotti, L.J.

1987-01-01

A single equation is derived for the determination of the first-order correction to the frequency-dependent density, due to the perturbation of a time-varying electric field. This new expression for the first-order correction to the frequency-dependent Kohn-Sham amplitudes depends explicitly upon the velocity form of the dipole-moment operator and the square of the Kohn-Sham Hamiltonian

Functional strategies of tropical dry forest plants in relation to growth form and isotopic composition

Science.gov (United States)

Santiago, L. S.; Silvera, K.; Andrade, J. L.; Dawson, T. E.

2017-11-01

Tropical dry forests (TDFs) undergo a substantial dry season in which plant species must endure several months of drought. Although TDFs support a diverse array of plant growth forms, it is not clear how they vary in mechanisms for coping with seasonal drought. We measured organic tissue stable isotopic composition of carbon (δ13C) and nitrogen (δ15N) across six plant growth forms including epiphytes, terrestrial succulents, trees, shrubs, herbs, and vines, and oxygen (δ18O) of four growth forms, to distinguish among patterns of resource acquisition and evaluate mechanisms for surviving annual drought in a lowland tropical dry forest in Yucatan, Mexico. Terrestrial succulent and epiphyte δ13C was around -14‰, indicating photosynthesis through the Crassulacean acid metabolism pathway, and along with one C4 herb were distinct from mean values of all other growth forms, which were between -26 and -29‰ indicating C3 photosynthesis. Mean tissue δ15N across epiphytes was -4.95‰ and was significantly lower than all other growth forms, which had values around +3‰. Tissue N concentration varied significantly among growth forms with epiphytes and terrestrial succulents having significantly lower values of about 1% compared to trees, shrubs, herbs and vines, which were around 3%. Tissue C concentration was highest in trees, shrubs and vines, intermediate in herbs and epiphytes and lowest in terrestrial succulents. δ18O did not vary among growth forms. Overall, our results suggest several water-saving aspects of resource acquisition, including the absolute occurrence of CAM photosynthesis in terrestrial succulents and epiphytes, high concentrations of leaf N in some species, which may facilitate CO2 drawdown by photosynthetic enzymes for a given stomatal conductance, and potentially diverse N sources ranging from atmospheric N in epiphytes with extremely depleted δ15N values, and a large range of δ15N values among trees, many of which are legumes and dry season

A hepatitis C virus infection model with time-varying drug effectiveness: solution and analysis.

Directory of Open Access Journals (Sweden)

Jessica M Conway

2014-08-01

Full Text Available Simple models of therapy for viral diseases such as hepatitis C virus (HCV or human immunodeficiency virus assume that, once therapy is started, the drug has a constant effectiveness. More realistic models have assumed either that the drug effectiveness depends on the drug concentration or that the effectiveness varies over time. Here a previously introduced varying-effectiveness (VE model is studied mathematically in the context of HCV infection. We show that while the model is linear, it has no closed-form solution due to the time-varying nature of the effectiveness. We then show that the model can be transformed into a Bessel equation and derive an analytic solution in terms of modified Bessel functions, which are defined as infinite series, with time-varying arguments. Fitting the solution to data from HCV infected patients under therapy has yielded values for the parameters in the model. We show that for biologically realistic parameters, the predicted viral decay on therapy is generally biphasic and resembles that predicted by constant-effectiveness (CE models. We introduce a general method for determining the time at which the transition between decay phases occurs based on calculating the point of maximum curvature of the viral decay curve. For the parameter regimes of interest, we also find approximate solutions for the VE model and establish the asymptotic behavior of the system. We show that the rate of second phase decay is determined by the death rate of infected cells multiplied by the maximum effectiveness of therapy, whereas the rate of first phase decline depends on multiple parameters including the rate of increase of drug effectiveness with time.

Mediation analysis with time varying exposures and mediators.

Science.gov (United States)

VanderWeele, Tyler J; Tchetgen Tchetgen, Eric J

2017-06-01

In this paper we consider causal mediation analysis when exposures and mediators vary over time. We give non-parametric identification results, discuss parametric implementation, and also provide a weighting approach to direct and indirect effects based on combining the results of two marginal structural models. We also discuss how our results give rise to a causal interpretation of the effect estimates produced from longitudinal structural equation models. When there are time-varying confounders affected by prior exposure and mediator, natural direct and indirect effects are not identified. However, we define a randomized interventional analogue of natural direct and indirect effects that are identified in this setting. The formula that identifies these effects we refer to as the "mediational g-formula." When there is no mediation, the mediational g-formula reduces to Robins' regular g-formula for longitudinal data. When there are no time-varying confounders affected by prior exposure and mediator values, then the mediational g-formula reduces to a longitudinal version of Pearl's mediation formula. However, the mediational g-formula itself can accommodate both mediation and time-varying confounders and constitutes a general approach to mediation analysis with time-varying exposures and mediators.

Dispersal of grouper larvae drives local resource sharing in a coral reef fishery

KAUST Repository

Almany, Glenn R.; Hamilton, Richard J.; Bode, Michael; Matawai, Manuai; Potuku, Tapas; Saenz Agudelo, Pablo; Planes, Serge; Berumen, Michael L.; Rhodes, Kevin L.; Thorrold, Simon R.; Russ, Garry Ronald; Jones, Geoffrey P.

2013-01-01

In many tropical nations, fisheries management requires a community-based approach because small customary marine tenure areas define the spatial scale of management [1]. However, the fate of larvae originating from a community's tenure is unknown, and thus the degree to which a community can expect their management actions to replenish the fisheries within their tenure is unclear [2, 3]. Furthermore, whether and how much larval dispersal links tenure areas can provide a strong basis for cooperative management [4, 5]. Using genetic parentage analysis, we measured larval dispersal from a single, managed spawning aggregation of squaretail coral grouper (Plectropomus areolatus) and determined its contribution to fisheries replenishment within five community tenure areas up to 33 km from the aggregation at Manus Island, Papua New Guinea. Within the community tenure area containing the aggregation, 17%-25% of juveniles were produced by the aggregation. In four adjacent tenure areas, 6%-17% of juveniles were from the aggregation. Larval dispersal kernels predict that 50% of larvae settled within 14 km of the aggregation. These results strongly suggest that both local and cooperative management actions can provide fisheries benefits to communities over small spatial scales. © 2013 Elsevier Ltd.

Dispersal of grouper larvae drives local resource sharing in a coral reef fishery

KAUST Repository

Almany, Glenn R.

2013-04-01

In many tropical nations, fisheries management requires a community-based approach because small customary marine tenure areas define the spatial scale of management [1]. However, the fate of larvae originating from a community\\'s tenure is unknown, and thus the degree to which a community can expect their management actions to replenish the fisheries within their tenure is unclear [2, 3]. Furthermore, whether and how much larval dispersal links tenure areas can provide a strong basis for cooperative management [4, 5]. Using genetic parentage analysis, we measured larval dispersal from a single, managed spawning aggregation of squaretail coral grouper (Plectropomus areolatus) and determined its contribution to fisheries replenishment within five community tenure areas up to 33 km from the aggregation at Manus Island, Papua New Guinea. Within the community tenure area containing the aggregation, 17%-25% of juveniles were produced by the aggregation. In four adjacent tenure areas, 6%-17% of juveniles were from the aggregation. Larval dispersal kernels predict that 50% of larvae settled within 14 km of the aggregation. These results strongly suggest that both local and cooperative management actions can provide fisheries benefits to communities over small spatial scales. © 2013 Elsevier Ltd.

Effects of curved midline and varying width on the description of the effective diffusivity of Brownian particles

Science.gov (United States)

Chávez, Yoshua; Chacón-Acosta, Guillermo; Dagdug, Leonardo

2018-05-01

Axial diffusion in channels and tubes of smoothly-varying geometry can be approximately described as one-dimensional diffusion in the entropy potential with a position-dependent effective diffusion coefficient, by means of the modified Fick–Jacobs equation. In this work, we derive analytical expressions for the position-dependent effective diffusivity for two-dimensional asymmetric varying-width channels, and for three-dimensional curved midline tubes, formed by straight walls. To this end, we use a recently developed theoretical framework using the Frenet–Serret moving frame as the coordinate system (2016 J. Chem. Phys. 145 074105). For narrow tubes and channels, an effective one-dimensional description reducing the diffusion equation to a Fick–Jacobs-like equation in general coordinates is used. From this last equation, one can calculate the effective diffusion coefficient applying Neumann boundary conditions.

Eestlased Karlovy Varys / J. R.

Index Scriptorium Estoniae

J. R.

2007-01-01

Ilmar Raagi mängufilm "Klass" osaleb 42. Karlovy Vary rahvusvahelise filmifestivali võistlusprogrammis "East of the West" ja Asko Kase lühimängufilm "Zen läbi prügi" on valitud festivali kõrvalprogrammi "Forum of Independents"

Numerical Methods for Plate Forming by Line Heating

DEFF Research Database (Denmark)

Clausen, Henrik Bisgaard

2000-01-01

Line heating is the process of forming originally flat plates into a desired shape by means of heat treatment. Parameter studies are carried out on a finite element model to provide knowledge of how the process behaves with varying heating conditions. For verification purposes, experiments are ca...... are carried out; one set of experiments investigates the actual heat flux distribution from a gas torch and another verifies the validty of the FE calculations. Finally, a method to predict the heating pattern is described....

Explicit analytical solution of a pendulum with periodically varying length

International Nuclear Information System (INIS)

Yang Tianzhi; Fang Bo; Li Song; Huang Wenhu

2010-01-01

A pendulum with periodically varying length is an interesting physical system. It has been studied by some researchers using traditional perturbation methods (for example, the averaging method). But due to the limitation of the conventional perturbation methods, the solutions are not valid for long-term prediction of the pendulum. In this paper, we use the homotopy analysis method to explore the approximate solution to this system. The method can easily self-adjust and control the convergence region. By applying the method to the governing equation of the pendulum, we obtain the approximation solution in a closed form. It is shown by the numerical method that the homotopy analysis method supplies a more accurate analytical solution for predicting the long-term behaviour of the pendulum. We believe that this system may be a good example for undergraduate and graduate students for better understanding of nonlinear oscillations.

Metallic nanomaterials formed by exerting large plastic strains

International Nuclear Information System (INIS)

Richert, M; Richert, J.; Zasadzinski, J.; Hawrylkiewicz, S.

2002-01-01

The investigations included pure Al and Cu single crystals, AlMg5 alloy and AlCuZr alloy have been presented. The materials were deformed by the cyclic extrusion compression method (CEC) within the range of true strains φ = 0.4-59.8 (1 to 67 deformation cycles by the CEC method). In all examined materials a strong tendency to form banded was observed. Within the range of very large plastic strains there was observed intensive rebuilding of the banded microstructure into subgrains, at first of rhombic shape, and next into equiaxial subgrains. A characteristic feature of the newly formed subgrains, not encountered in the range of conventional deformations, was the occurrence of large misorientation angles between the newly formed subgrains. The proportion of large misorientation angles in the microstructure varied, and it increased with increasing deformation. Reduction of the recovery process in AlMg5 and AlCuZr alloys preserved the growth of the newly formed nanograins, favoring the retaining of the nanomeric dimensions. This results show that there is the effective possibility of production of metallic nanomaterials by exerting of very large nonconventional plastic strains. (author)

Friction and lubrication modelling in sheet metal forming: Influence of lubrication amount, tool roughness and sheet coating on product quality

Science.gov (United States)

Hol, J.; Wiebenga, J. H.; Carleer, B.

2017-09-01

In the stamping of automotive parts, friction and lubrication play a key role in achieving high quality products. In the development process of new automotive parts, it is therefore crucial to accurately account for these effects in sheet metal forming simulations. This paper presents a selection of results considering friction and lubrication modelling in sheet metal forming simulations of a front fender product. For varying lubrication conditions, the front fender can either show wrinkling or fractures. The front fender is modelled using different lubrication amounts, tool roughness’s and sheet coatings to show the strong influence of friction on both part quality and the overall production stability. For this purpose, the TriboForm software is used in combination with the AutoForm software. The results demonstrate that the TriboForm software enables the simulation of friction behaviour for varying lubrication conditions, i.e. resulting in a generally applicable approach for friction characterization under industrial sheet metal forming process conditions.

The method of normal forms for singularly perturbed systems of Fredholm integro-differential equations with rapidly varying kernels

Energy Technology Data Exchange (ETDEWEB)

Bobodzhanov, A A; Safonov, V F [National Research University " Moscow Power Engineering Institute" , Moscow (Russian Federation)

2013-07-31

The paper deals with extending the Lomov regularization method to classes of singularly perturbed Fredholm-type integro-differential systems, which have not so far been studied. In these the limiting operator is discretely noninvertible. Such systems are commonly known as problems with unstable spectrum. Separating out the essential singularities in the solutions to these problems presents great difficulties. The principal one is to give an adequate description of the singularities induced by 'instability points' of the spectrum. A methodology for separating singularities by using normal forms is developed. It is applied to the above type of systems and is substantiated in these systems. Bibliography: 10 titles.

Form of the manifestly covariant Lagrangian

Science.gov (United States)

Johns, Oliver Davis

1985-10-01

The preferred form for the manifestly covariant Lagrangian function of a single, charged particle in a given electromagnetic field is the subject of some disagreement in the textbooks. Some authors use a ``homogeneous'' Lagrangian and others use a ``modified'' form in which the covariant Hamiltonian function is made to be nonzero. We argue in favor of the ``homogeneous'' form. We show that the covariant Lagrangian theories can be understood only if one is careful to distinguish quantities evaluated on the varied (in the sense of the calculus of variations) world lines from quantities evaluated on the unvaried world lines. By making this distinction, we are able to derive the Hamilton-Jacobi and Klein-Gordon equations from the ``homogeneous'' Lagrangian, even though the covariant Hamiltonian function is identically zero on all world lines. The derivation of the Klein-Gordon equation in particular gives Lagrangian theoretical support to the derivations found in standard quantum texts, and is also shown to be consistent with the Feynman path-integral method. We conclude that the ``homogeneous'' Lagrangian is a completely adequate basis for covariant Lagrangian theory both in classical and quantum mechanics. The article also explores the analogy with the Fermat theorem of optics, and illustrates a simple invariant notation for the Lagrangian and other four-vector equations.

Comparison of Linear Microinstability Calculations of Varying Input Realism

International Nuclear Information System (INIS)

Rewoldt, G.

2003-01-01

The effect of varying ''input realism'' or varying completeness of the input data for linear microinstability calculations, in particular on the critical value of the ion temperature gradient for the ion temperature gradient mode, is investigated using gyrokinetic and gyrofluid approaches. The calculations show that varying input realism can have a substantial quantitative effect on the results

Comparison of linear microinstability calculations of varying input realism

International Nuclear Information System (INIS)

Rewoldt, G.; Kinsey, J.E.

2004-01-01

The effect of varying 'input realism' or varying completeness of the input data for linear microinstability calculations, in particular on the critical value of the ion temperature gradient for the ion temperature gradient mode, is investigated using gyrokinetic and gyrofluid approaches. The calculations show that varying input realism can have a substantial quantitative effect on the results

Varied line-space gratings: past, present and future

International Nuclear Information System (INIS)

Hettrick, M.C.

1985-08-01

A classically ruled diffraction grating consists of grooves which are equidistant, straight and parallel. Conversely, the so-called ''holographic'' grating (formed by the interfering waves of coherent visible light), although severely constrained by the recording wavelength and recording geometry, has grooves which are typically neither equidistant, straight nor parallel. In contrast, a varied line-space (VLS) grating, in common nomenclature, is a design in which the groove positions are relatively unconstrained yet possess sufficient symmetry to permit mechanical ruling. Such seemingly exotic gratings are no longer only a theoretical curiosity, but have been ruled and used in a wide variety of applications. These include: (1) aberration-corrected normal incidence concave gratings for Seya-Namioka monochromators and optical de-multiplexers, (2) flat-field grazing incidence concave gratings for plasma diagnostics, (3) aberration-corrected grazing incidence plane gratings for space-borne spectrometers, (4) focusing grazing incidence plane grating for synchrotron radiation monochromators, and (5) wavefront generators for visible interferometry of optical surfaces (particularly aspheres). Future prospects of VLS gratings as dispersing elements, wavefront correctors and beamsplitters appear promising. The author discusses the history of VLS gratings, their present applications, and their potential in the future. 61 refs., 24 figs

A statistical theory of cell killing by radiation of varying linear energy transfer

International Nuclear Information System (INIS)

Hawkins, R.B.

1994-01-01

A theory is presented that provides an explanation for the observed features of the survival of cultured cells after exposure to densely ionizing high-linear energy transfer (LET) radiation. It starts from a phenomenological postulate based on the linear-quadratic form of cell survival observed for low-LET radiation and uses principles of statistics and fluctuation theory to demonstrate that the effect of varying LET on cell survival can be attributed to random variation of dose to small volumes contained within the nucleus. A simple relation is presented for surviving fraction of cells after exposure to radiation of varying LET that depends on the α and β parameters for the same cells in the limit of low-LET radiation. This relation implies that the value of β is independent of LET. Agreement of the theory with selected observations of cell survival from the literature is demonstrated. A relation is presented that gives relative biological effectiveness (RBE) as a function of the α and β parameters for low-LET radiation. Measurements from microdosimetry are used to estimate the size of the subnuclear volume to which the fluctuation pertains. 11 refs., 4 figs., 2 tabs

Efficiency of Different Nitrogen Forms in Buckwheat (Fagopyrum esculentum Moench

Directory of Open Access Journals (Sweden)

Burhan Kara

2016-06-01

Full Text Available The research was carried out with aim to determination the efficient of nitrogen forms (ammonium sulfate, ammonium nitrate and urea on nitrogen use efficient for buckwheat in Isparta during 2014 and 2015 years. All the examined characteristics were determined higher values in applied nitrogen forms according to non-nitrogen parcel. In compared to nitrogen forms, the highest grain yield (1456 and 1325 kg ha-1, biological yield (4873 and 4512 kg ha-1, 1000 grain weight (24.9 and 24.8 g, agronomic efficient (24.96% and 24.25%, recycling efficient (0.24% and 0.22% and utilization efficient (0.25% and 0.18% were obtained from ammonium sulfate, the highest protein content (11.37% and 12.44% and agro-physiological efficient (0.27% and 0.24% from ammonium nitrate in both years. Among the nitrogen forms weren’t significant differently in physiological efficient in both years, recycling and utilization efficient in the first year. The mineral nutrient content varied according to nitrogen forms. Generally, ammonium sulfate was positive effect to yield and some quality parameters.

Informed consent and the readability of the written consent form.

Science.gov (United States)

Sivanadarajah, N; El-Daly, I; Mamarelis, G; Sohail, M Z; Bates, P

2017-11-01

Introduction The aim of this study was to objectively ascertain the level of readability of standardised consent forms for orthopaedic procedures. Methods Standardised consent forms (both in summary and detailed formats) endorsed by the British Orthopaedic Association (BOA) were retrieved from orthoconsent.com and assessed for readability. This involved using an online tool to calculate the validated Flesch reading ease score (FRES). This was compared with the FRES for the National Health Service (NHS) Consent Form 1. Data were analysed and interpreted according to the FRES grading table. Results The FRES for Consent Form 1 was 55.6, relating to the literacy expected of an A level student. The mean FRES for the BOA summary consent forms (n=27) was 63.6 (95% confidence interval [CI]: 61.2-66.0) while for the detailed consent forms (n=32), it was 68.9 (95% CI: 67.7-70.0). All BOA detailed forms scored >60, correlating to the literacy expected of a 13-15-year-old. The detailed forms had a higher FRES than the summary forms (p<0.001). Conclusions This study demonstrates that the BOA endorsed standardised consent forms are much easier to read and understand than the NHS Consent Form 1, with the detailed BOA forms being the easiest to read. Despite this, owing to varying literacy levels, a significant proportion of patients may struggle to give informed consent based on the written information provided to them.

Phosphorus forms in soils of Oban Hills, Akamkpa, Cross River State ...

African Journals Online (AJOL)

Oban Hills is located at Akamkpa in the Southern Senatorial District of Cross River, State, Nigeria. Phosphorus (P)-rich soil from the Hills is expected to have an effect on retention and distribution in the highly acidic soils surrounding the area inundated for several years. Phosphorus forms in the soils of the Hills varied with ...

Marketingový mix HC Enegie Karlovy Vary

OpenAIRE

Štrobl, Adam

2016-01-01

Title: Marketing mix of HC Energie Karlovy Vary Objectives: This thesis is based on a questionnaire responses obtained from HC Energie Karlovy Vary fans. Its objective is focused on evaluation of their opinions on the marketing mix, their subsequent interpretation, and finally even development of recommendations for improvement based on previous analysis. Methods: Two methods are used to analyse the marketing mix. The first method is qualitative participant observation. The second method is a...

Õunpuu Karlovy Varys edukas

Index Scriptorium Estoniae

2010-01-01

45. Karlovy Vary filmifestivali võistlusprogrammis "East of the West" märgiti ära Veiko Õunpuu film "Püha Tõnu kiusamine". Peaauhind läks rumeenlase Cristi Puiu filmile "Aurora". Grand prix´sai Augustĺ Vila film "La mosquitera". Teisi preemiasaajaid

Stability Analysis and Stabilization of T-S Fuzzy Delta Operator Systems with Time-Varying Delay via an Input-Output Approach

Directory of Open Access Journals (Sweden)

Zhixiong Zhong

2013-01-01

Full Text Available The stability analysis and stabilization of Takagi-Sugeno (T-S fuzzy delta operator systems with time-varying delay are investigated via an input-output approach. A model transformation method is employed to approximate the time-varying delay. The original system is transformed into a feedback interconnection form which has a forward subsystem with constant delays and a feedback one with uncertainties. By applying the scaled small gain (SSG theorem to deal with this new system, and based on a Lyapunov Krasovskii functional (LKF in delta operator domain, less conservative stability analysis and stabilization conditions are obtained. Numerical examples are provided to illustrate the advantages of the proposed method.

Global Stability of Polytopic Linear Time-Varying Dynamic Systems under Time-Varying Point Delays and Impulsive Controls

Directory of Open Access Journals (Sweden)

M. de la Sen

2010-01-01

Full Text Available This paper investigates the stability properties of a class of dynamic linear systems possessing several linear time-invariant parameterizations (or configurations which conform a linear time-varying polytopic dynamic system with a finite number of time-varying time-differentiable point delays. The parameterizations may be timevarying and with bounded discontinuities and they can be subject to mixed regular plus impulsive controls within a sequence of time instants of zero measure. The polytopic parameterization for the dynamics associated with each delay is specific, so that (q+1 polytopic parameterizations are considered for a system with q delays being also subject to delay-free dynamics. The considered general dynamic system includes, as particular cases, a wide class of switched linear systems whose individual parameterizations are timeinvariant which are governed by a switching rule. However, the dynamic system under consideration is viewed as much more general since it is time-varying with timevarying delays and the bounded discontinuous changes of active parameterizations are generated by impulsive controls in the dynamics and, at the same time, there is not a prescribed set of candidate potential parameterizations.

An Economic Model of Workplace Mobbing in Academe

Science.gov (United States)

Faria, Joao Ricardo; Mixon, Franklin G., Jr.; Salter, Sean P.

2012-01-01

Workplace bullying or mobbing can be defined as the infliction of various forms of abuse (e.g., verbal, emotional, psychological) against a colleague or subordinate by one or more other members of a workplace. Even in the presence of academic tenure, workplace mobbing remains a prevalent issue in academe. This study develops an economic model that…

Between Monitoring and Modeling

DEFF Research Database (Denmark)

Haldrup, Karin

2008-01-01

The paper analyses spatial dimensions of land tenure security in situations, where land tenure is predominantly informal, as is the case in major parts of the world. It takes its point of departure in a dilemma constituted by: - on one side, the complexity of land tenure issues, and - on the othe...

Brief communication: A nonlinear self-similar solution to barotropic flow over varying topography

Science.gov (United States)

Ibanez, Ruy; Kuehl, Joseph; Shrestha, Kalyan; Anderson, William

2018-03-01

Beginning from the shallow water equations (SWEs), a nonlinear self-similar analytic solution is derived for barotropic flow over varying topography. We study conditions relevant to the ocean slope where the flow is dominated by Earth's rotation and topography. The solution is found to extend the topographic β-plume solution of Kuehl (2014) in two ways. (1) The solution is valid for intensifying jets. (2) The influence of nonlinear advection is included. The SWEs are scaled to the case of a topographically controlled jet, and then solved by introducing a similarity variable, η = cxnxyny. The nonlinear solution, valid for topographies h = h0 - αxy3, takes the form of the Lambert W-function for pseudo velocity. The linear solution, valid for topographies h = h0 - αxy-γ, takes the form of the error function for transport. Kuehl's results considered the case -1 ≤ γ < 1 which admits expanding jets, while the new result considers the case γ < -1 which admits intensifying jets and a nonlinear case with γ = -3.

Evolution of perturbation in charge-varying dusty plasmas

International Nuclear Information System (INIS)

Popel, S.I.; Golub, A.P.; Losseva, T.V.; Bingham, R.; Benkadda, S.

2001-01-01

The nonstationary problem of the evolution of perturbation and its transformation into nonlinear wave structure in dusty plasmas is considered. For this purpose two one-dimensional models based on a set of fluid equations, Poisson's equation, and a charging equation for dust are developed. The first (simplified) model corresponds to the case [Popel et al., Phys. Plasmas 3, 4313 (1996)] when exact steady-state shock wave solutions can exist. This simplified model includes variable-charged dust grains, Boltzmann electrons, and inertial ions. The second (ionization source) model takes into account the variation of the ion density and the ion momentum dissipation due to dust particle charging as well as the source of plasma particles due to ionization process. The computational method for solving the set of equations which describe the evolution in time of a nonlinear structure in a charge-varying dusty plasma is developed. The case of the evolution of an intensive initial nonmoving region with a constant enhanced ion density is investigated on the basis of these two models. The consideration within the ionization source model is performed for the data of the laboratory experiment [Luo et al., Phys. Plasmas 6, 3455 (1999)]. It is shown that the ionization source model allows one to obtain shock structures as a result of evolution of an initial perturbation and to explain the experimental value of the width of the shock wave front. Comparison of the numerical data obtained on the basis of the ionization source model and the simplified model shows that the main characteristic features of the shock structure are the same for both models. Nevertheless, the ionization source model is much more sensitive to the form of the initial perturbation than the simplified model. The solution of the problem of the evolution of perturbation and its transformation into shock wave in charge-varying dusty plasmas opens up possibilities for description of the real phenomena like supernova

Hermite-Gaussian beams with self-forming spiral phase distribution

Science.gov (United States)

Zinchik, Alexander A.; Muzychenko, Yana B.

2014-05-01

Spiral laser beams is a family of laser beams that preserve the structural stability up to scale and rotate with the propagation. Properties of spiral beams are of practical interest for laser technology, medicine and biotechnology. Researchers use a spiral beams for movement and manipulation of microparticles. Spiral beams have a complicated phase distribution in cross section. This paper describes the results of analytical and computer simulation of Hermite-Gaussian beams with self-forming spiral phase distribution. In the simulation used a laser beam consisting of the sum of the two modes HG TEMnm and TEMn1m1. The coefficients n1, n, m1, m were varied. Additional phase depending from the coefficients n, m, m1, n1 imposed on the resulting beam. As a result, formed the Hermite Gaussian beam phase distribution which takes the form of a spiral in the process of distribution. For modeling was used VirtualLab 5.0 (manufacturer LightTrans GmbH).

Optimization of Single Point Incremental Forming of Al5052-O Sheet

Energy Technology Data Exchange (ETDEWEB)

Kim, Chan Il; Xiao, Xiao; Do, Van Cuong; Kim, Young Suk [Kyungpook Nat’l Univ., Daegu (Korea, Republic of)

2017-03-15

Single point incremental forming (SPIF) is a sheet-forming technique. It is a die-less sheet metal manufacturing process for rapid prototyping and small batch production. The Critical parameters in the forming process include tool diameter, step depth, feed rate, spindle speed, etc. In this study, these parameters and the die shape corresponding to the Varying Wall Angle Conical Frustum(VWACF) model were used for forming 0.8mm in thick Al5052-O sheets. The Taguchi method of Experiments of Design (DOE) and Grey relational optimization were used to determine the optimum parameters in SPIF. A response study was performed on formability, spring back, and thickness reduction. The research shows that the optimum combination of these parameters that yield best performance of SPIF is as follows: tool diameter, 6mm; spin speed, 60rpm; step depth, 0.3mm; and feed rate, 500mm/min.

Optimistlik Karlovy Vary / Jaan Ruus

Index Scriptorium Estoniae

Ruus, Jaan, 1938-2017

2007-01-01

42. Karlovy Vary rahvusvahelise filmifestivali auhinnatud filmidest (žürii esimees Peter Bart). Kristallgloobuse sai Islandi-Saksamaa "Katseklaasilinn" (režii Baltasar Kormakur), parimaks režissööriks tunnistati norralane Bard Breien ("Negatiivse mõtlemise kunst"). Austraallase Michael James Rowlandi "Hea õnne teekond" sai žürii eripreemia

Reversing Course: The Troubled State of Academic Staffing and a Path Forward

Science.gov (United States)

American Federation of Teachers (NJ), 2008

2008-01-01

Over the last generation, the instructional staffing system in American higher education has experienced a significant reduction in the proportion of jobs for full-time tenured and tenure-track faculty members and a dramatic growth in fixed-term full- and part-time instructional jobs without tenure. About 70 percent of the people teaching in…

Time-varying value of electric energy efficiency

Energy Technology Data Exchange (ETDEWEB)

Mims, Natalie A.; Eckman, Tom; Goldman, Charles

2017-06-30

Electric energy efficiency resources save energy and may reduce peak demand. Historically, quantification of energy efficiency benefits has largely focused on the economic value of energy savings during the first year and lifetime of the installed measures. Due in part to the lack of publicly available research on end-use load shapes (i.e., the hourly or seasonal timing of electricity savings) and energy savings shapes, consideration of the impact of energy efficiency on peak demand reduction (i.e., capacity savings) has been more limited. End-use load research and the hourly valuation of efficiency savings are used for a variety of electricity planning functions, including load forecasting, demand-side management and evaluation, capacity and demand response planning, long-term resource planning, renewable energy integration, assessing potential grid modernization investments, establishing rates and pricing, and customer service. This study reviews existing literature on the time-varying value of energy efficiency savings, provides examples in four geographically diverse locations of how consideration of the time-varying value of efficiency savings impacts the calculation of power system benefits, and identifies future research needs to enhance the consideration of the time-varying value of energy efficiency in cost-effectiveness screening analysis. Findings from this study include: -The time-varying value of individual energy efficiency measures varies across the locations studied because of the physical and operational characteristics of the individual utility system (e.g., summer or winter peaking, load factor, reserve margin) as well as the time periods during which savings from measures occur. -Across the four locations studied, some of the largest capacity benefits from energy efficiency are derived from the deferral of transmission and distribution system infrastructure upgrades. However, the deferred cost of such upgrades also exhibited the greatest range

Experimental evidence for amplitude death induced by a time-varying interaction

Energy Technology Data Exchange (ETDEWEB)

Suresh, K. [Centre for Nonlinear Dynamics, School of Physics, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu (India); Shrimali, M.D. [Department of Physics, Central University of Rajasthan, NH-8, Bandar Sindri, Ajmer 305 801 (India); Prasad, Awadhesh [Department of Physics and Astrophysics, University of Delhi, Delhi 110 007 (India); Thamilmaran, K., E-mail: maran.cnld@gmail.com [Centre for Nonlinear Dynamics, School of Physics, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu (India)

2014-08-01

In this paper, we study the time-varying interaction in coupled oscillatory systems. For this purpose, we have designed a novel time-varying resistive network using an analog switch and inverter circuits. We have applied this time-varying resistive network to mutually coupled identical Chua's oscillators. When the resistances are varied in time, we find that amplitude death arises in coupled identical oscillators. This has been observed numerically as well as verified through hardware experiments. - Highlights: • We have implemented the time-varying interaction in coupled oscillatory systems. • We have designed a novel time-varying resistive network using an analog switch and inverter circuits. • When the resistances are varied in time, we find that amplitude death arises in coupled identical oscillators.

Brane world cosmologies with varying speed of light

International Nuclear Information System (INIS)

Youm, Donam

2001-02-01

We study cosmologies in the Randall-Sundrum models, incorporating the possibility of time-varying speed of light and Newton's constant. The cosmologies with varying speed of light (VSL) were proposed by Moffat and by Albrecht and Magueijo as an alternative to inflation for solving the cosmological problems. We consider the case in which the speed of light varies with time after the radion or the scale of the extra dimension has been stabilized. We elaborate on the conditions under which the flatness problem and the cosmological constant problem can be resolved. Particularly, the VSL cosmologies may provide a possible mechanism for bringing the quantum corrections to the fine-tuned brane tensions after the SUSY breaking under control. (author)

Horizontal career changes as an alternative to premature exit from work.

Science.gov (United States)

Aleksandrowicz, Paula; Zieschang, Hanna; Bräunig, Dietmar; Jahn, Frauke

2014-01-01

Certain workplaces are called jobs with limited tenure. Due to physical or psychosocial risk factors, often coupled with qualification mismatches, workers cannot grow old in them. That may lead to premature exit into retirement, to a period of drawing a work incapacity pension or to a long spell of unemployment. A horizontal career change, which enables the worker to move on to a less burdening workplace while preserving social status, is a possible solution. The objective of the "Horizontal career change-a new job opportunity for older employees" project is to develop a model of career changes for workers employed in jobs with limited tenure and to implement it in the form of an information- and communication technology-based tool. Possible applications range from individual career planning, through institutionalized vocational reintegration, to personnel development in small and medium-sized enterprises.

Morphology of silicon carbide formed by chemical vapour deposition

International Nuclear Information System (INIS)

Pampuch, R.; Stobierski, L.

1977-01-01

Silicon carbide polycrystalline layers and particulate crystals were obtained in a modified van Arkel-de Boer apparatus on SiC-covered graphite and molybdenum susceptors. Gaseous SiCl 4 + CCl 4 + H 2 reactive mixtures with Si/C mole ratios varying between 0.9 and 1.4 and with Cl/Cl + H ratios varying between 2.10 -5 and 1.10 -3 were used. The morphology and structure of SiC products obtained at temperatures between 1400 and 1900 0 C and input gas flow rates between 5.10 -4 and 6.10 -2 moles per hour have been systematically investigated by scanning electronmicrographs, X-rays (using the Laue, Weissenberg, and rotation photographers), IR-spectra, and under the polarising microscope. The ranges of temperature and input gas flow rates in which the given habits and forms of the SiC products are formed have been assessed. The habits of the particulate crystals as function of temperature have been interpreted in terms of the existing theories of heterogeneous nucleation assuming layer growth of the crystals by two-dimensional nucleation. The influence of the composition of the gaseous mixtures upon the formation of the 2H polytype as well as the probable reasons for the common occurrence of stacking fault twins in the 3C polytype have been discussed. (author)

Cellobiose fermenting yeast produces varied forms of native ß-glucosidase

Science.gov (United States)

The rapid growing yeast strain NRRL Y-50464 is robust to environmental stress and resistant to 2-furaldehyde (furfural) and 5-[hydroxymethyl]-2-furaldehyde (HMF). It is able to utilize cellobiose as its sole source of carbon and produces ethanol from lignocellulosic biomass by simultaneous saccharif...

Conservative flight with a varying load factor and closed form ...

Indian Academy of Sciences (India)

Conservative flight performance of an aircraft with constant load factor was analysed by ... Within the frame work of flat earth hypotheses the equations of motion of an aircraft as obtained by ..... load factor function if this inequality holds good.

Preferences for different nitrogen forms by coexisting plant species and soil microbes.

Science.gov (United States)

Harrison, Kathryn A; Bol, Roland; Bardgett, Richard D

2007-04-01

The growing awareness that plants might use a variety of nitrogen (N) forms, both organic and inorganic, has raised questions about the role of resource partitioning in plant communities. It has been proposed that coexisting plant species might be able to partition a limited N pool, thereby avoiding competition for resources, through the uptake of different chemical forms of N. In this study, we used in situ stable isotope labeling techniques to assess whether coexisting plant species of a temperate grassland (England, UK) display preferences for different chemical forms of N, including inorganic N and a range of amino acids of varying complexity. We also tested whether plants and soil microbes differ in their preference for different N forms, thereby relaxing competition for this limiting resource. We examined preferential uptake of a range of 13C15N-labeled amino acids (glycine, serine, and phenylalanine) and 15N-labeled inorganic N by coexisting grass species and soil microbes in the field. Our data show that while coexisting plant species simultaneously take up a variety of N forms, including inorganic N and amino acids, they all showed a preference for inorganic N over organic N and for simple over the more complex amino acids. Soil microbes outcompeted plants for added N after 50 hours, but in the long-term (33 days) the proportion of added 15N contained in the plant pool increased for all N forms except for phenylalanine, while the proportion in the microbial biomass declined relative to the first harvest. These findings suggest that in the longer-term plants become more effective competitors for added 15N. This might be due to microbial turnover releasing 15N back into the plant-soil system or to the mineralization and subsequent plant uptake of 15N transferred initially to the organic matter pool. We found no evidence that soil microbes preferentially utilize any of the N forms added, despite previous studies showing that microbial preferences for N forms

Variation in Orthologous Shell-Forming Proteins Contribute to Molluscan Shell Diversity.

Science.gov (United States)

Jackson, Daniel J; Reim, Laurin; Randow, Clemens; Cerveau, Nicolas; Degnan, Bernard M; Fleck, Claudia

2017-11-01

Despite the evolutionary success and ancient heritage of the molluscan shell, little is known about the molecular details of its formation, evolutionary origins, or the interactions between the material properties of the shell and its organic constituents. In contrast to this dearth of information, a growing collection of molluscan shell-forming proteomes and transcriptomes suggest they are comprised of both deeply conserved, and lineage specific elements. Analyses of these sequence data sets have suggested that mechanisms such as exon shuffling, gene co-option, and gene family expansion facilitated the rapid evolution of shell-forming proteomes and supported the diversification of this phylum specific structure. In order to further investigate and test these ideas we have examined the molecular features and spatial expression patterns of two shell-forming genes (Lustrin and ML1A2) and coupled these observations with materials properties measurements of shells from a group of closely related gastropods (abalone). We find that the prominent "GS" domain of Lustrin, a domain believed to confer elastomeric properties to the shell, varies significantly in length between the species we investigated. Furthermore, the spatial expression patterns of Lustrin and ML1A2 also vary significantly between species, suggesting that both protein architecture, and the regulation of spatial gene expression patterns, are important drivers of molluscan shell evolution. Variation in these molecular features might relate to certain materials properties of the shells of these species. These insights reveal an important and underappreciated source of variation within shell-forming proteomes that must contribute to the diversity of molluscan shell phenotypes. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Combined time-varying forecast based on the proper scoring approach for wind power generation

DEFF Research Database (Denmark)

Chen, Xingying; Jiang, Yu; Yu, Kun

2017-01-01

Compared with traditional point forecasts, combined forecast have been proposed as an effective method to provide more accurate forecasts than individual model. However, the literature and research focus on wind-power combined forecasts are relatively limited. Here, based on forecasting error...... distribution, a proper scoring approach is applied to combine plausible models to form an overall time-varying model for the next day forecasts, rather than weights-based combination. To validate the effectiveness of the proposed method, real data of 3 years were used for testing. Simulation results...... demonstrate that the proposed method improves the accuracy of overall forecasts, even compared with a numerical weather prediction....

Tracking time-varying coefficient-functions

DEFF Research Database (Denmark)

Nielsen, Henrik Aalborg; Nielsen, Torben Skov; Joensen, Alfred K.

2000-01-01

is a combination of recursive least squares with exponential forgetting and local polynomial regression. It is argued, that it is appropriate to let the forgetting factor vary with the value of the external signal which is the argument of the coefficient functions. Some of the key properties of the modified method...... are studied by simulation...

Esmaklassiline Karlovy Vary / Jaanus Noormets

Index Scriptorium Estoniae

Noormets, Jaanus

2007-01-01

Ilmar Raagi mängufilm "Klass" võitis 42. Karlovy Vary rahvusvahelise filmifestivalil kaks auhinda - ametliku kõrvalvõistlusprogrammi "East of the West" eripreemia "Special mention" ja Euroopa väärtfilmikinode keti Europa Cinemas preemia. Ka Asko Kase lühifilmi "Zen läbi prügi linastumisest ning teistest auhinnasaajatest ning osalejatest

Time-varying predictability in crude-oil markets: the case of GCC countries

International Nuclear Information System (INIS)

El Hedi Arouri, Mohamed; Thanh Huong Dinh; Duc Khuong Nguyen

2010-01-01

This paper uses a time-varying parameter model with generalized autoregressive conditional heteroscedasticity effects to examine the dynamic behavior of crude-oil prices for the period February 7, 1997-January 8, 2010. Using data from four countries of the Gulf Cooperation Council, we find evidence of short-term predictability in oil-price changes over time, except for several short sub-periods. However, the hypothesis of convergence towards weak-form informational efficiency is rejected for all markets. In addition, we explore the possibility of structural breaks in the time-paths of the estimated predictability indices and detect only one breakpoint, for the oil markets in Qatar and the United Arab Emirates. Our empirical results therefore call for new empirical research to further gauge the predictability characteristics and the determinants of oil-price changes.

Analysis of time-varying psoriasis lesion image patterns

DEFF Research Database (Denmark)

Maletti, Gabriela Mariel; Ersbøll, Bjarne Kjær; Nielsen, Allan Aasbjerg

2004-01-01

The multivariate alteration detection transform is applied to pairs of within and between time varying registered psoriasis image patterns. Color band contribution to the variates explaining maximal change is analyzed.......The multivariate alteration detection transform is applied to pairs of within and between time varying registered psoriasis image patterns. Color band contribution to the variates explaining maximal change is analyzed....

Specimen loading list for the varying temperature experiment

International Nuclear Information System (INIS)

Qualls, A.L.; Sitterson, R.G.

1998-01-01

The varying temperature experiment HFIR-RB-13J has been assembled and inserted in the reactor. Approximately 5300 specimens were cleaned, inspected, matched, and loaded into four specimen holders. A listing of each specimen loaded into the steady temperature holder, its position in the capsule, and the identification of the corresponding specimen loaded into the varying temperature holder is presented in this report

Effect of land-use on the P forms of an Andisol

Directory of Open Access Journals (Sweden)

Carlos Henríquez

2015-11-01

Full Text Available The effect of agricultural land use on the forms of P in a Typic Hapludand was evaluated. An area of 8.4 ha composed of 3 adjacent lots, dedicated for over 20 years to secondary forest and plantings of sugarcane and coffee, was chosen at Juan Viñas, Costa Rica. Soil samples were taken using an 8x6 grid layout of sampling points, spaced at 40 m. Soil samples were analyzed with the P fractionation methodology proposed by Hedley et ál. (1982. Total P varied between 936 and 2516 mg.kg-1. Both coffee and sugar cane lots (1934 y 1754 mg.kg-1 respectively, showed the highest values of total-P compared with the forest (1419 mg.kg- 1, suggesting a positive overall balance of P due to its accumulation through the years. The coffee area showed the highest values of P-labile and P-sesquioxides-Fe/Al, which was related to usual higher fertilization compared with areas of sugarcane and forest. The greatest value of P-residual was found in sugarcane with almost 48% of total P. The P-organic varied 27 to 29% of the total suggesting its importance as valuable sink of P. We conclude that the type of land use had a significant effect on the forms of P which was observed in both the quantity and distributionof different forms of P in soil.

In temperature forming of friction stir lap welds in aluminium alloys

Science.gov (United States)

Bruni, Carlo; Cabibbo, Marcello; Greco, Luciano; Pieralisi, Massimiliano

2018-05-01

The objective of such investigation is the study in depth of the forming phase of welds realized on three sheet metal blanks in aluminium alloys by friction stir lap welding. Such forming phase was performed by upsetting at different constant forming temperatures varying from 200°C to 350°C with constant ram velocities of 0.01 and 0.1 mm/s. The temperature values were obtained by the use of heating strips applied on the upper tool and on the lower tool. It was observed an increase in the friction factor, acting at the upsetting tool-workpiece interface, with increasing temperature that is very useful in producing the required localized deformation with which to improve the weld. It was also confirmed that the forming phase allows to realize a required thickness in the weld area allowing to neglect the surficial perturbation produced by the friction stir welding tool shoulder. The obtained thickness could be subjected to springback when too low temperatures are considered.

Varied line-space gratings and applications

International Nuclear Information System (INIS)

McKinney, W.R.

1991-01-01

This paper presents a straightforward analytical and numerical method for the design of a specific type of varied line-space grating system. The mathematical development will assume plane or nearly-plane spherical gratings which are illuminated by convergent light, which covers many interesting cases for synchrotron radiation. The gratings discussed will have straight grooves whose spacing varies across the principal plane of the grating. Focal relationships and formulae for the optical grating-pole-to-exist-slit distance and grating radius previously presented by other authors will be derived with a symbolic algebra system. It is intended to provide the optical designer with the tools necessary to design such a system properly. Finally, some possible advantages and disadvantages for application to synchrotron to synchrotron radiation beamlines will be discussed

Creep rupture properties under varying load/temperature conditions on a nickel-base heat-resistant alloy strengthened by boron addition

International Nuclear Information System (INIS)

Tsuji, Hirokazu; Tanabe, Tatsuhiko; Nakajima, Hajime

1994-01-01

A series of constant load and temperature creep rupture tests and varying load and temperature creep rupture tests was carried out on Hastelloy XR whose boron content level is 60 mass ppm at 900 and 1000 C in order to examine the behavior of the alloy under varying load and temperature conditions. The life fraction rule completely fails in the prediction of the creep rupture life under varying load and temperature conditions though the rule shows good applicability for Hastelloy XR whose boron content level is below 10 mass ppm. The modified life fraction rule has been proposed based on the dependence of the creep rupture strength on the boron content level of the alloy. The modified rule successfully predicts the creep rupture life under the test conditions from 1000 to 900 C. The trend observed in the tests from 900 to 1000 C can be qualitatively explained by the mechanism that the oxide film which is formed during the prior exposure to 900 C plays the role of the protective barrier against the boron dissipation into the environment. (orig.)

Eesti film võistleb Karlovy Varys

Index Scriptorium Estoniae

2008-01-01

8. juulil esilinastub Karlovy Vary filmifestivalil Rene Vilbre noortefilm "Mina olin siin", mille aluseks on Sass Henno romaan "Mina olin siin. Esimene arest", stsenaariumi kirjutas Ilmar Raag. Film võistleb võistlusprogrammis "East of the West"

"Nuove" forme di trasferimento di risorse private. (“New” directions for private resource transfers)

OpenAIRE

P. STREETEN

2013-01-01

A partire dagli anni 1960 e 1970 vi è stata una crescente tendenza a aggiungere alle forme tradizionali di controllo in modo che possa essere condivisa a vari livelli e può essere limitato ad aree specifiche . Inoltre, queste modalità possono cambiare nel tempo . Queste " nuove forme di investimenti stranieri " sono stati più evidenti nei settori del petrolio e dei metalli , ma anche nel settore manifatturiero , in particolare per i mercati dei paesi ospitanti e nelle industrie con tecnologie...

Entropy Rate of Time-Varying Wireless Networks

DEFF Research Database (Denmark)

Cika, Arta; Badiu, Mihai Alin; Coon, Justin P.

2018-01-01

In this paper, we present a detailed framework to analyze the evolution of the random topology of a time-varying wireless network via the information theoretic notion of entropy rate. We consider a propagation channel varying over time with random node positions in a closed space and Rayleigh...... fading affecting the connections between nodes. The existence of an edge between two nodes at given locations is modeled by a Markov chain, enabling memory effects in network dynamics. We then derive a lower and an upper bound on the entropy rate of the spatiotemporal network. The entropy rate measures...

Multivariate time-varying volatility modeling using probabilistic fuzzy systems

NARCIS (Netherlands)

Basturk, N.; Almeida, R.J.; Golan, R.; Kaymak, U.

2016-01-01

Methods to accurately analyze financial risk have drawn considerable attention in financial institutions. One difficulty in financial risk analysis is the fact that banks and other financial institutions invest in several assets which show time-varying volatilities and hence time-varying financial

Densified waste form and method for forming

Science.gov (United States)

Garino, Terry J.; Nenoff, Tina M.; Sava Gallis, Dorina Florentina

2015-08-25

Materials and methods of making densified waste forms for temperature sensitive waste material, such as nuclear waste, formed with low temperature processing using metallic powder that forms the matrix that encapsulates the temperature sensitive waste material. The densified waste form includes a temperature sensitive waste material in a physically densified matrix, the matrix is a compacted metallic powder. The method for forming the densified waste form includes mixing a metallic powder and a temperature sensitive waste material to form a waste form precursor. The waste form precursor is compacted with sufficient pressure to densify the waste precursor and encapsulate the temperature sensitive waste material in a physically densified matrix.

Three-form periods on Calabi-Yau fourfolds: toric hypersurfaces and F-theory applications

Energy Technology Data Exchange (ETDEWEB)

Greiner, Sebastian; Grimm, Thomas W. [Institute for Theoretical Physics and Center for Extreme Matter and Emergent Phenomena, Utrecht University,Leuvenlaan 4, 3584 CE Utrecht (Netherlands); Max-Planck-Institut für Physik, Föhringer Ring 6, 80805 Munich (Germany)

2017-05-30

The study of the geometry of Calabi-Yau fourfolds is relevant for compactifications of string theory, M-theory, and F-theory to various dimensions. This work introduces the mathematical machinery to derive the complete moduli dependence of the periods of non-trivial three-forms for fourfolds realized as hypersurfaces in toric ambient spaces. It sets the stage to determine Picard-Fuchs-type differential equations and integral expressions for these forms. The key tool is the observation that non-trivial three-forms on fourfold hypersurfaces in toric ambient spaces always stem from divisors that are build out of trees of toric surfaces fibered over Riemann surfaces. The three-form periods are then non-trivially related to the one-form periods of these Riemann surfaces. In general, the three-form periods are known to vary holomorphically over the complex structure moduli space and play an important role in the effective actions arising in fourfold compactifications. We discuss two explicit example fourfolds for F-theory compactifications in which the three-form periods determine axion decay constants.

Renal cells express different forms of vimentin: the independent expression alteration of these forms is important in cell resistance to osmotic stress and apoptosis.

Directory of Open Access Journals (Sweden)

Bettina S Buchmaier

Full Text Available Osmotic stress has been shown to regulate cytoskeletal protein expression. It is generally known that vimentin is rapidly degraded during apoptosis by multiple caspases, resulting in diverse vimentin fragments. Despite the existence of the known apoptotic vimentin fragments, we demonstrated in our study the existence of different forms of vimentin VIM I, II, III, and IV with different molecular weights in various renal cell lines. Using a proteomics approach followed by western blot analyses and immunofluorescence staining, we proved the apoptosis-independent existence and differential regulation of different vimentin forms under varying conditions of osmolarity in renal cells. Similar impacts of osmotic stress were also observed on the expression of other cytoskeleton intermediate filament proteins; e.g., cytokeratin. Interestingly, 2D western blot analysis revealed that the forms of vimentin are regulated independently of each other under glucose and NaCl osmotic stress. Renal cells, adapted to high NaCl osmotic stress, express a high level of VIM IV (the form with the highest molecular weight, besides the three other forms, and exhibit higher resistance to apoptotic induction with TNF-α or staurosporin compared to the control. In contrast, renal cells that are adapted to high glucose concentration and express only the lower-molecular-weight forms VIM I and II, were more susceptible to apoptosis. Our data proved the existence of different vimentin forms, which play an important role in cell resistance to osmotic stress and are involved in cell protection against apoptosis.

On the form of ROCs constructed from confidence ratings.

Science.gov (United States)

Malmberg, Kenneth J

2002-03-01

A classical question for memory researchers is whether memories vary in an all-or-nothing, discrete manner (e.g., stored vs. not stored, recalled vs. not recalled), or whether they vary along a continuous dimension (e.g., strength, similarity, or familiarity). For yes-no classification tasks, continuous- and discrete-state models predict nonlinear and linear receiver operating characteristics (ROCs), respectively (D. M. Green & J. A. Swets, 1966; N. A. Macmillan & C. D. Creelman, 1991). Recently, several authors have assumed that these predictions are generalizable to confidence ratings tasks (J. Qin, C. L. Raye, M. K. Johnson, & K. J. Mitchell, 2001; S. D. Slotnick, S. A. Klein, C. S. Dodson, & A. P. Shimamura, 2000, and A. P. Yonelinas, 1999). This assumption is shown to be unwarranted by showing that discrete-state ratings models predict both linear and nonlinear ROCs. The critical factor determining the form of the discrete-state ROC is the response strategy adopted by the classifier.

Experiments on moisture form of concrete and adhesion of paints

International Nuclear Information System (INIS)

Kita, Daizo; Sumino, Masahiro

1975-01-01

It is necessary for radiation-resisting paints to adhere tightly to concrete in order to exhibit superior effects. As adhesion of paints to concrete is greatly affected by moisture content of concrete, this content is checked severely in the field. However, it may be considered that adhesion will be affected by the form of the moisture in the concrete also. Therefore, experiments were conducted with mortar to investigate the interrelations between pF-moisture content, moisture form and adhesion of paint. The following results were obtained: 1) Adhesion of paint becomes stronger as moisture content falls. 2) Adhesion strength of paint rises sharply until moisture content falls to a pF-value of 5.5 after which the strength is increased gradually until moisture content reaches pF of 7.0. 3) The pF-moisture content of 5.5 varies greatly depending on the mix proportions of mortar, but the form of moisture in such cases remains fixed and unchanged. (auth.)

Cabinet Governance and Political Stability in English Urban Councils

Directory of Open Access Journals (Sweden)

Stephen Greasley

2011-12-01

Full Text Available Policy-makers have long been concerned with the quality of local political leadership and have often resorted to institutional reform to try to improve political leadership. This paper looks at a specific and neglected facet of the political management reforms that have been implemented in English local government over the last decade: the tenure and turnover of cabinet members. The tenure of top politicians may be an important influence on the performance of local government particularly when political management is designed to favour individualised leadership. On the one hand, excessively short tenures for top politicians may damage the ability of governments to develop strategic plans and ensure they are implemented while on the other hand the risk of loss of office is central to political accountability and excessively long tenures may be indicative of an insulated and unresponsive elite. While some research attention has been paid to the tenures of leaders of councils in England there is little systematic information about the tenure of cabinet members. This paper discusses the relevance of cabinet stability and provides an overview of recent experience in England.

Relativistic form factors for clusters with nonrelativistic wave functions

International Nuclear Information System (INIS)

Mitra, A.N.; Kumari, I.

1977-01-01

Using a simple variant of an argument employed by Licht and Pagnamenta (LP) on the effect of Lorentz contraction on the elastic form factors of clusters with nonrelativistic wave functions, it is shown how their result can be generalized to inelastic form factors so as to produce (i) a symmetrical appearance of Lorentz contraction effects in the initial and final states, and (ii) asymptotic behavior in accord with dimensional scaling theories. A comparison of this result with a closely analogous parametric form obtained by Brodsky and Chertok from a propagator chain model leads, with plausible arguments, to the conclusion of an effective mass M for the cluster, with M 2 varying as the number n of the quark constituents, instead of as n 2 . A further generalization of the LP formula is obtained for an arbitrary duality-diagram vertex, again with asymptotic behavior in conformity with dimensional scaling. The practical usefulness of this approach is emphasized as a complementary tool to those of high-energy physics for phenomenological fits to data up to moderate values of q 2

Knowledge sharing behaviour and demographic variables amongst secondary school teachers in and around Gaborone, Botswana

Directory of Open Access Journals (Sweden)

Isaac C. Mogotsi

2011-11-01

Full Text Available The purpose of this study was to investigate the relationships between knowledge sharing behaviour and the demographic variables gender, age, organisational tenure and professional tenure. Following a correlational survey approach, the study sourced its data from senior secondary school teachers in and around Gaborone, Botswana. Knowledge sharing behaviour was measured using an instrument sourced from the extant literature. No statistically significant relationship was detected between knowledge sharing behaviour and gender, age, or professional tenure. Only organisational tenure weakly negatively correlated with knowledge sharing behaviour. Thus, according to these findings, demographic variables do not appear to be important determinants of knowledge sharing behaviour.

MM99.70 - MODELS FOR FRICTION AND MATERIAL STRESS STRAIN HARDENING IN COLD FORMING

DEFF Research Database (Denmark)

Eriksen, Morten

1999-01-01

and tool temperature for four different combination of basic material, conversion layer and lubricant. Furthermore flow stress curves for aluminium, steel and stainless steel are given at varying slug temperatures in the range which can be reached in cold forming (25-200C).The documentation is divided...

Free Vibration Behavior of a Gradient Elastic Beam with Varying Cross Section

Directory of Open Access Journals (Sweden)

Mustafa Özgür Yayli

2014-01-01

Full Text Available Based on strain gradient elasticity theory, a finite element procedure is proposed for computation of natural frequencies for the microbeams of constant width and linear varying depth. Weak form formulation of the equation of motion is obtained first as in common classical finite element procedure in terms of various kinds of boundary conditions. Gradient elastic shape functions are used for interpolating deflection inside a finite element. Stiffness and mass matrices are then calculated to solve the microbeam eigen value problem. A solution for natural frequencies is obtained using characteristic equation of microbeam in gradient elasticity. The results are given in a series of figures and compared with their classical counterparts. The effect of various slope values on the natural frequencies are examined in some numerical examples. Comparison with the classical elasticity theory is also performed to verify the present study.

Genetic polymorphisms in varied environments.

Science.gov (United States)

Powell, J R

1971-12-03

Thirteen experimenital populationis of Drosophila willistoni were maintained in cages, in some of which the environments were relatively constant and in others varied. After 45 weeks, the populations were assayed by gel electrophoresis for polymorphisms at 22 protein loci. The average heterozygosity per individual and the average unmber of alleles per locus were higher in populations maintained in heterogeneous environments than in populations in more constant enviroments.

Pemodelan Markov Switching Dengan Time-varying Transition Probability

OpenAIRE

Savitri, Anggita Puri; Warsito, Budi; Rahmawati, Rita

2016-01-01

Exchange rate or currency is an economic variable which reflects country's state of economy. It fluctuates over time because of its ability to switch the condition or regime caused by economic and political factors. The changes in the exchange rate are depreciation and appreciation. Therefore, it could be modeled using Markov Switching with Time-Varying Transition Probability which observe the conditional changes and use information variable. From this model, time-varying transition probabili...

Central recirculation zone analysis in an unconfined tangential swirl burner with varying degrees of premixing

Energy Technology Data Exchange (ETDEWEB)

Valera-Medina, A. [CIATEQ, Parque Industrial Bernardo Quintana, Turbomachinery Department, Queretaro (Mexico); Syred, N.; Kay, P.; Griffiths, A. [Cardiff University, School of Engineering, Cardiff, Wales (United Kingdom)

2011-06-15

Swirl-stabilised combustion is one of the most widely used techniques for flame stabilisation, uses ranging from gas turbine combustors to pulverised coal-fired power stations. In gas turbines, lean premixed systems are of especial importance, giving the ability to produce low NOx systems coupled with wide stability limits. The common element is the swirl burner, which depends on the generation of an aerodynamically formed central recirculation zone (CRZ) and which serves to recycle heat and active chemical species to the root of the flame as well as providing low-velocity regions where the flame speed can match the local flow velocity. Enhanced mixing in and around the CRZ is another beneficial feature. The structure of the CRZ and hence that of the associated flames, stabilisation and mixing processes have shown to be extremely complex, three-dimensional and time dependent. The characteristics of the CRZ depend very strongly on the level of swirl (swirl number), burner configuration, type of flow expansion, Reynolds number (i.e. flowrate) and equivalence ratio. Although numerical methods have had some success when compared to experimental results, the models still have difficulties at medium to high swirl levels, with complex geometries and varied equivalence ratios. This study thus focuses on experimental results obtained to characterise the CRZ formed under varied combustion conditions with different geometries and some variation of swirl number in a generic swirl burner. CRZ behaviour has similarities to the equivalent isothermal state, but is strongly dependent on equivalence ratio, with interesting effects occurring with a high-velocity fuel injector. Partial premixing and combustion cause more substantive changes to the CRZ than pure diffusive combustion. (orig.)

Observer-based linear parameter varying H∞ tracking control for hypersonic vehicles

Directory of Open Access Journals (Sweden)

Yiqing Huang

2016-11-01

Full Text Available This article aims to develop observer-based linear parameter varying output feedback H∞ tracking controller for hypersonic vehicles. Due to the complexity of an original nonlinear model of the hypersonic vehicle dynamics, a slow–fast loop linear parameter varying polytopic model is introduced for system stability analysis and controller design. Then, a state observer is developed by linear parameter varying technique in order to estimate the unmeasured attitude angular for slow loop system. Also, based on the designed linear parameter varying state observer, a kind of attitude tracking controller is presented to reduce tracking errors for all bounded reference attitude angular inputs. The closed-loop linear parameter varying system is proved to be quadratically stable by Lypapunov function technique. Finally, simulation results show that the developed linear parameter varying H∞ controller has good tracking capability for reference commands.

Estrelas variáveis

OpenAIRE

Viana, Sérgio Manuel de Oliveira

2001-01-01

A observação do céu nocturno é uma prática que vem da Antiguidade. Desde então e durante muito tempo pensou-se que as estrelas mantinham o brilho constante. Assim foi até ao século XVI, quando David Fabricius observou uma estrela cujo brilho variava periodicamente. Dois séculos mais tarde, Jonh Goodricke descobriu uma segunda estrela e com o desenvolvimento de instrumentos de observação este conjunto foi muito alargado e hoje inclui o Sol.A variação do brilho das estrelas variáveis permite d...

Exponentially varying viscosity of magnetohydrodynamic mixed convection Eyring-Powell nanofluid flow over an inclined surface

Science.gov (United States)

Khan, Imad; Fatima, Sumreen; Malik, M. Y.; Salahuddin, T.

2018-03-01

This paper explores the theoretical study of the steady incompressible two dimensional MHD boundary layer flow of Eyring-Powell nanofluid over an inclined surface. The fluid is considered to be electrically conducting and the viscosity of the fluid is assumed to be varying exponentially. The governing partial differential equations (PDE's) are reduced into ordinary differential equations (ODE's) by applying similarity approach. The resulting ordinary differential equations are solved successfully by using Homotopy analysis method. The impact of pertinent parameters on velocity, concentration and temperature profiles are examined through graphs and tables. Also coefficient of skin friction, Sherwood and Nusselt numbers are illustrated in tabular and graphical form.

Vesicle biomechanics in a time-varying magnetic field.

Science.gov (United States)

Ye, Hui; Curcuru, Austen

2015-01-01

Cells exhibit distortion when exposed to a strong electric field, suggesting that the field imposes control over cellular biomechanics. Closed pure lipid bilayer membranes (vesicles) have been widely used for the experimental and theoretical studies of cellular biomechanics under this electrodeformation. An alternative method used to generate an electric field is by electromagnetic induction with a time-varying magnetic field. References reporting the magnetic control of cellular mechanics have recently emerged. However, theoretical analysis of the cellular mechanics under a time-varying magnetic field is inadequate. We developed an analytical theory to investigate the biomechanics of a modeled vesicle under a time-varying magnetic field. Following previous publications and to simplify the calculation, this model treated the inner and suspending media as lossy dielectrics, the membrane thickness set at zero, and the electric resistance of the membrane assumed to be negligible. This work provided the first analytical solutions for the surface charges, electric field, radial pressure, overall translational forces, and rotational torques introduced on a vesicle by the time-varying magnetic field. Frequency responses of these measures were analyzed, particularly the frequency used clinically by transcranial magnetic stimulation (TMS). The induced surface charges interacted with the electric field to produce a biomechanical impact upon the vesicle. The distribution of the induced surface charges depended on the orientation of the coil and field frequency. The densities of these charges were trivial at low frequency ranges, but significant at high frequency ranges. The direction of the radial force on the vesicle was dependent on the conductivity ratio between the vesicle and the medium. At relatively low frequencies (biomechanics under a time-varying magnetic field. Biological effects of clinical TMS are not likely to occur via alteration of the biomechanics of brain

Familial forms of diabetes insipidus: clinical and molecular characteristics.

Science.gov (United States)

Babey, Muriel; Kopp, Peter; Robertson, Gary L

2011-07-05

Over the past two decades, the genetic and molecular basis of familial forms of diabetes insipidus has been elucidated. Diabetes insipidus is a clinical syndrome characterized by the excretion of abnormally large volumes of diluted urine (polyuria) and increased fluid intake (polydipsia). The most common type of diabetes insipidus is caused by lack of the antidiuretic hormone arginine vasopressin (vasopressin), which is produced in the hypothalamus and secreted by the neurohypophysis. This type of diabetes insipidus is referred to here as neurohypophyseal diabetes insipidus. The syndrome can also result from resistance to the antidiuretic effects of vasopressin on the kidney, either at the level of the vasopressin 2 receptor or the aquaporin 2 water channel (which mediates the re-absorption of water from urine), and is referred to as renal or nephrogenic diabetes insipidus. Differentiation between these two types of diabetes insipidus and primary polydipsia can be difficult owing to the existence of partial as well as complete forms of vasopressin deficiency or resistance. Seven different familial forms of diabetes insipidus are known to exist. The clinical presentation, genetic basis and cellular mechanisms responsible for them vary considerably. This information has led to improved methods of differential diagnosis and could provide the basis of new forms of therapy.

Effect of loading pattern on longitudinal bowing in flexible roll forming

Energy Technology Data Exchange (ETDEWEB)

Kim, Jae Hyun; Woo, Young Yun; Hwang, Tae Woo; Han, Sang Wook; Moon, Young Hoon [School of Mechanical Engineering, Engineering Research Center for Net Shape and Die Manufacturing, Pusan National University,Busan (Korea, Republic of)

2016-12-15

The flexible roll forming process can be used to fabricate products with a variable cross-section profile in the longitudinal direction. Transversal nonuniformity of the longitudinal strain is one of the fundamental characteristics of blank deformation in flexible roll forming. Longitudinal bowing is a shape defect caused by transversal nonuniformity of the longitudinal strain. In this study, loading patterns in flexible roll forming are investigated in order to reduce the longitudinal bowing in a roll-formed blank. To analyze the effects of loading patterns on longitudinal bowing, two different forming schedules are implemented. In schedule 1, loading patterns with different bending angle increments are designed under fixed initial and final bending angles. In schedule 2, loading patterns with different initial bending angles under the fixed final bending angle are designed. Our results show that the bowing heights are significantly affected by the loading patterns. The bowing susceptibilities vary with blank shape such as trapezoid, convex, and concave shapes. In addition to the peak longitudinal strain at the respective roll stands, the cumulative longitudinal strain from the initial to final stands is shown to be a reliable index in predicting the tendency of longitudinal bowing.

Time-Varying Value of Energy Efficiency in Michigan

Energy Technology Data Exchange (ETDEWEB)

Mims, Natalie; Eckman, Tom; Schwartz, Lisa C.

2018-04-02

Quantifying the time-varying value of energy efficiency is necessary to properly account for all of its benefits and costs and to identify and implement efficiency resources that contribute to a low-cost, reliable electric system. Historically, most quantification of the benefits of efficiency has focused largely on the economic value of annual energy reduction. Due to the lack of statistically representative metered end-use load shape data in Michigan (i.e., the hourly or seasonal timing of electricity savings), the ability to confidently characterize the time-varying value of energy efficiency savings in the state, especially for weather-sensitive measures such as central air conditioning, is limited. Still, electric utilities in Michigan can take advantage of opportunities to incorporate the time-varying value of efficiency into their planning. For example, end-use load research and hourly valuation of efficiency savings can be used for a variety of electricity planning functions, including load forecasting, demand-side management and evaluation, capacity planning, long-term resource planning, renewable energy integration, assessing potential grid modernization investments, establishing rates and pricing, and customer service (KEMA 2012). In addition, accurately calculating the time-varying value of efficiency may help energy efficiency program administrators prioritize existing offerings, set incentive or rebate levels that reflect the full value of efficiency, and design new programs.

Forms of organic phosphorus in wetland soils

Science.gov (United States)

Cheesman, A. W.; Turner, B. L.; Reddy, K. R.

2014-12-01

Phosphorus (P) cycling in freshwater wetlands is dominated by biological mechanisms, yet there has been no comprehensive examination of the forms of biogenic P (i.e., forms derived from biological activity) in wetland soils. We used solution 31P NMR spectroscopy to identify and quantify P forms in surface soils of 28 palustrine wetlands spanning a range of climatic, hydrogeomorphic, and vegetation types. Total P concentrations ranged between 51 and 3516 μg P g-1, of which an average of 58% was extracted in a single-step NaOH-EDTA procedure. The extracts contained a broad range of P forms, including phosphomonoesters (averaging 24% of the total soil P), phosphodiesters (averaging 10% of total P), phosphonates (up to 4% of total P), and both pyrophosphate and long-chain polyphosphates (together averaging 6% of total P). Soil P composition was found to be dependant upon two key biogeochemical properties: organic matter content and pH. For example, stereoisomers of inositol hexakisphosphate were detected exclusively in acidic soils with high mineral content, while phosphonates were detected in soils from a broad range of vegetation and hydrogeomorphic types but only under acidic conditions. Conversely inorganic polyphosphates occurred in a broad range of wetland soils, and their abundance appears to reflect more broadly that of a "substantial" and presumably active microbial community with a significant relationship between total inorganic polyphosphates and microbial biomass P. We conclude that soil P composition varies markedly among freshwater wetlands but can be predicted by fundamental soil properties.

State-dependent differential Riccati equation to track control of time-varying systems with state and control nonlinearities.

Science.gov (United States)

Korayem, M H; Nekoo, S R

2015-07-01

This work studies an optimal control problem using the state-dependent Riccati equation (SDRE) in differential form to track for time-varying systems with state and control nonlinearities. The trajectory tracking structure provides two nonlinear differential equations: the state-dependent differential Riccati equation (SDDRE) and the feed-forward differential equation. The independence of the governing equations and stability of the controller are proven along the trajectory using the Lyapunov approach. Backward integration (BI) is capable of solving the equations as a numerical solution; however, the forward solution methods require the closed-form solution to fulfill the task. A closed-form solution is introduced for SDDRE, but the feed-forward differential equation has not yet been obtained. Different ways of solving the problem are expressed and analyzed. These include BI, closed-form solution with corrective assumption, approximate solution, and forward integration. Application of the tracking problem is investigated to control robotic manipulators possessing rigid or flexible joints. The intention is to release a general program for automatic implementation of an SDDRE controller for any manipulator that obeys the Denavit-Hartenberg (D-H) principle when only D-H parameters are received as input data. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

Error Analysis for RADAR Neighbor Matching Localization in Linear Logarithmic Strength Varying Wi-Fi Environment

Directory of Open Access Journals (Sweden)

Mu Zhou

2014-01-01

Full Text Available This paper studies the statistical errors for the fingerprint-based RADAR neighbor matching localization with the linearly calibrated reference points (RPs in logarithmic received signal strength (RSS varying Wi-Fi environment. To the best of our knowledge, little comprehensive analysis work has appeared on the error performance of neighbor matching localization with respect to the deployment of RPs. However, in order to achieve the efficient and reliable location-based services (LBSs as well as the ubiquitous context-awareness in Wi-Fi environment, much attention has to be paid to the highly accurate and cost-efficient localization systems. To this end, the statistical errors by the widely used neighbor matching localization are significantly discussed in this paper to examine the inherent mathematical relations between the localization errors and the locations of RPs by using a basic linear logarithmic strength varying model. Furthermore, based on the mathematical demonstrations and some testing results, the closed-form solutions to the statistical errors by RADAR neighbor matching localization can be an effective tool to explore alternative deployment of fingerprint-based neighbor matching localization systems in the future.

Error Analysis for RADAR Neighbor Matching Localization in Linear Logarithmic Strength Varying Wi-Fi Environment

Science.gov (United States)

Tian, Zengshan; Xu, Kunjie; Yu, Xiang

2014-01-01

This paper studies the statistical errors for the fingerprint-based RADAR neighbor matching localization with the linearly calibrated reference points (RPs) in logarithmic received signal strength (RSS) varying Wi-Fi environment. To the best of our knowledge, little comprehensive analysis work has appeared on the error performance of neighbor matching localization with respect to the deployment of RPs. However, in order to achieve the efficient and reliable location-based services (LBSs) as well as the ubiquitous context-awareness in Wi-Fi environment, much attention has to be paid to the highly accurate and cost-efficient localization systems. To this end, the statistical errors by the widely used neighbor matching localization are significantly discussed in this paper to examine the inherent mathematical relations between the localization errors and the locations of RPs by using a basic linear logarithmic strength varying model. Furthermore, based on the mathematical demonstrations and some testing results, the closed-form solutions to the statistical errors by RADAR neighbor matching localization can be an effective tool to explore alternative deployment of fingerprint-based neighbor matching localization systems in the future. PMID:24683349

Modelling Time-Varying Volatility in Financial Returns

DEFF Research Database (Denmark)

Amado, Cristina; Laakkonen, Helinä

2014-01-01

The “unusually uncertain” phase in the global financial markets has inspired many researchers to study the effects of ambiguity (or “Knightian uncertainty”) on the decisions made by investors and their implications for the capital markets. We contribute to this literature by using a modified...... version of the time-varying GARCH model of Amado and Teräsvirta (2013) to analyze whether the increasing uncertainty has caused excess volatility in the US and European government bond markets. In our model, volatility is multiplicatively decomposed into two time-varying conditional components: the first...... being captured by a stable GARCH(1,1) process and the second driven by the level of uncertainty in the financial market....

"Mina olin siin" esilinastub Karlovy Varys

Index Scriptorium Estoniae

2008-01-01

Karlovy Vary filmifestivalil esilinastub Rene Vilbre noortefilm "Mina olin siin", mille aluseks on Sass Henno romaan "Mina olin siin. Esimene arest", stsenaariumi kirjutas Ilmar Raag. Film võistleb võistlusprogrammis "East of the West". Esitlema sõidavad R. Vilbre, R. Sildos, R. Kaljujärv, T. Tuisk

Ellipsometry with randomly varying polarization states

NARCIS (Netherlands)

Liu, F.; Lee, C. J.; Chen, J. Q.; E. Louis,; van der Slot, P. J. M.; Boller, K. J.; F. Bijkerk,

2012-01-01

We show that, under the right conditions, one can make highly accurate polarization-based measurements without knowing the absolute polarization state of the probing light field. It is shown that light, passed through a randomly varying birefringent material has a well-defined orbit on the Poincar

Varying Constants, Gravitation and Cosmology

Directory of Open Access Journals (Sweden)

Jean-Philippe Uzan

2011-03-01

Full Text Available Fundamental constants are a cornerstone of our physical laws. Any constant varying in space and/or time would reflect the existence of an almost massless field that couples to matter. This will induce a violation of the universality of free fall. Thus, it is of utmost importance for our understanding of gravity and of the domain of validity of general relativity to test for their constancy. We detail the relations between the constants, the tests of the local position invariance and of the universality of free fall. We then review the main experimental and observational constraints that have been obtained from atomic clocks, the Oklo phenomenon, solar system observations, meteorite dating, quasar absorption spectra, stellar physics, pulsar timing, the cosmic microwave background and big bang nucleosynthesis. At each step we describe the basics of each system, its dependence with respect to the constants, the known systematic effects and the most recent constraints that have been obtained. We then describe the main theoretical frameworks in which the low-energy constants may actually be varying and we focus on the unification mechanisms and the relations between the variation of different constants. To finish, we discuss the more speculative possibility of understanding their numerical values and the apparent fine-tuning that they confront us with.

M3FT-17OR0301070211 - Preparation of Hot Isostatically Pressed AgZ Waste Form Samples

Energy Technology Data Exchange (ETDEWEB)

Jubin, Robert Thomas [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bruffey, Stephanie H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jordan, Jacob A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2017-10-01

The production of radioactive iodine-bearing waste forms that exhibit long-term stability and are suitable for permanent geologic disposal has been the subject of substantial research interest. One potential method of iodine waste form production is hot isostatic pressing (HIP). Recent studies at Oak Ridge National Laboratory (ORNL) have investigated the conversion of iodine-loaded silver mordenite (I-AgZ) directly to a waste form by HIP. ORNL has performed HIP with a variety of sample compositions and pressing conditions. The base mineral has varied among AgZ (in pure and engineered forms), silver-exchanged faujasite, and silverexchanged zeolite A. Two iodine loading methods, occlusion and chemisorption, have been explored. Additionally, the effects of variations in temperature and pressure of the process have been examined, with temperature ranges of 525°C–1,100°C and pressure ranges of 100–300 MPa. All of these samples remain available to collaborators upon request. The sample preparation detailed in this document is an extension of that work. In addition to previously prepared samples, this report documents the preparation of additional samples to support stability testing. These samples include chemisorbed I-AgZ and pure AgI. Following sample preparation, each sample was processed by HIP by American Isostatic Presses Inc. and returned to ORNL for storage. ORNL will store the samples until they are requested by collaborators for durability testing. The sample set reported here will support waste form durability testing across the national laboratories and will provide insight into the effects of varied iodine content on iodine retention by the produced waste form and on potential improvements in waste form durability provided by the zeolite matrix.

Harmonic Maass forms and mock modular forms

CERN Document Server

Bringmann, Kathrin; Ono, Ken

2017-01-01

Modular forms and Jacobi forms play a central role in many areas of mathematics. Over the last 10-15 years, this theory has been extended to certain non-holomorphic functions, the so-called "harmonic Maass forms". The first glimpses of this theory appeared in Ramanujan's enigmatic last letter to G. H. Hardy written from his deathbed. Ramanujan discovered functions he called "mock theta functions" which over eighty years later were recognized as pieces of harmonic Maass forms. This book contains the essential features of the theory of harmonic Maass forms and mock modular forms, together with a wide variety of applications to algebraic number theory, combinatorics, elliptic curves, mathematical physics, quantum modular forms, and representation theory.

Creep rupture properties under varying load/temperature conditions on a nickel-base heat-resistant alloy strengthened by boron addition

International Nuclear Information System (INIS)

Tsuji, Hirokazu; Nakajima, Hajime; Tanabe, Tatsuhiko.

1993-09-01

A series of constant load and temperature creep rupture tests and varying load and temperature creep rupture tests was carried out on Hastelloy XR whose boron content level is 60 mass ppm at 900 and 1000degC in order to examine the behavior of the alloy under varying load and temperature conditions. The life fraction rule completely fails in the prediction of the creep rupture life under varying load and temperature conditions though the rule shows good applicability for Hastelloy XR whose boron content level is below 10 mass ppm. The modified life fraction rule has been proposed based on the dependence of the creep rupture strength on the born content level of the alloy. The modified rule successfully predicts the creep rupture life under the test conditions from 1000degC to 900degC. The trend observed in the tests from 900degC to 1000degC can be qualitatively explained by the mechanism that the oxide film which is formed during the prior exposure to 900degC plays the role of the protective barrier against the boron dissipation into the environment. (author)

Partially linear varying coefficient models stratified by a functional covariate

KAUST Repository

Maity, Arnab; Huang, Jianhua Z.

2012-01-01

We consider the problem of estimation in semiparametric varying coefficient models where the covariate modifying the varying coefficients is functional and is modeled nonparametrically. We develop a kernel-based estimator of the nonparametric

Identification of time-varying nonlinear systems using differential evolution algorithm

DEFF Research Database (Denmark)

Perisic, Nevena; Green, Peter L; Worden, Keith

2013-01-01

(DE) algorithm for the identification of time-varying systems. DE is an evolutionary optimisation method developed to perform direct search in a continuous space without requiring any derivative estimation. DE is modified so that the objective function changes with time to account for the continuing......, thus identification of time-varying systems with nonlinearities can be a very challenging task. In order to avoid conventional least squares and gradient identification methods which require uni-modal and double differentiable objective functions, this work proposes a modified differential evolution...... inclusion of new data within an error metric. This paper presents results of identification of a time-varying SDOF system with Coulomb friction using simulated noise-free and noisy data for the case of time-varying friction coefficient, stiffness and damping. The obtained results are promising and the focus...

Compilation of Instantaneous Source Functions for Varying ...

African Journals Online (AJOL)

Compilation of Instantaneous Source Functions for Varying Architecture of a Layered Reservoir with Mixed Boundaries and Horizontal Well Completion Part IV: Normal and Inverted Letter 'h' and 'H' Architecture.

Short form of Demodex species mite in the dog: occurrence and measurements.

Science.gov (United States)

Chesney, C J

1999-02-01

A form of Demodex species mite shorter in length than Demodex canis was found in six consecutive cases of canine demodicosis. The mean length of the parasite was 122.6 microns (SD 12.0 microns, 39 mites counted), significantly shorter than either male or female forms of D canis (P < 0.0001). The proportion of short to long mites in each case varied from 0.5 to 22 per 100. In young dogs, skin signs associated with the presence of mites were first noted after about seven months, while in the oldest subject the disease became apparent at 10 years of age. This form of mite has now been found in four countries over three continents, the findings suggesting that it is not uncommon and is acquired in puppyhood, although it may be carried unnoticed for many years.

Uptake of different forms of nitrogen by hyphae of arbuscular mycorrhizal fungi

International Nuclear Information System (INIS)

Li Xia; Zhang Junling

2007-01-01

A two-compartment incorporating air-gap device and 15 N-labeling technique was used to investigate the uptake of different forms of N by arbuscular mycorrhizal fungi (AMF). Maize (Zea mays L.) was in association with Glomus mosseae, or Glomus intraradices. Solutions labeled with different forms of 15 N were supplied to the hyphae compartment 48 h before harvesting. The results showed that the uptake capability of 15 N varied with fungi species and N forms supplied. Percentage of 15 N taken up over 48 h by G. intraradices was higher than that by G. mosseae. The uptake capability of 15 N by AMF was in the order of 15 NH 4 + > 15 N-Gln> 15 N-Gly> 15 NO 3 - . 15 N uptake by AMF hyphae accounted for 0.005-0.032% of total N uptake. (authors)

Final Project Report CFA-14-6357: A New Paradigm for Understanding Multiphase Ceramic Waste Form Performance

Energy Technology Data Exchange (ETDEWEB)

Brinkman, Kyle [Clemson Univ., SC (United States); Bordia, Rajendra [Clemson Univ., SC (United States); Reifsnider, Kenneth [Univ. of South Carolina, Columbia, SC (United States); Chiu, Wilson [Univ. of Connecticut, Storrs, CT (United States); Amoroso, Jake [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2017-12-28

This project fabricated model multiphase ceramic waste forms with processing-controlled microstructures followed by advanced characterization with synchrotron and electron microscopy-based 3D tomography to provide elemental and chemical state-specific information resulting in compositional phase maps of ceramic composites. Details of 3D microstructural features were incorporated into computer-based simulations using durability data for individual constituent phases as inputs in order to predict the performance of multiphase waste forms with varying microstructure and phase connectivity.

Top down and bottom up selection drives variations in frequency and form of a visual signal

OpenAIRE

Yeh, Chien-Wei; Blamires, Sean J.; Liao, Chen-Pan; Tso, I.-Min

2015-01-01

The frequency and form of visual signals can be shaped by selection from predators, prey or both. When a signal simultaneously attracts predators and prey, selection may favour a strategy that minimizes risks while attracting prey. Accordingly, varying the frequency and form of the silken decorations added to their web may be a way that Argiope spiders minimize predation while attracting prey. Nonetheless, the role of extraneous factors renders the influences of top down and bottom up selecti...

Computer simulation of the Blumlein pulse forming network

International Nuclear Information System (INIS)

Edwards, C.B.

1981-03-01

A computer simulation of the Blumlein pulse-forming network is described. The model is able to treat the case of time varying loads, non-zero conductor resistance, and switch closure effects as exhibited by real systems employing non-ohmic loads such as field-emission vacuum diodes in which the impedance is strongly time and voltage dependent. The application of the code to various experimental arrangements is discussed, with particular reference to the prediction of the behaviour of the output circuit of 'ELF', the electron beam generator in operation at the Rutherford Laboratory. The output from the code is compared directly with experimentally obtained voltage waveforms applied to the 'ELF' diode. (author)

Women and landed property in urban India: Negotiating closed doors and windows of opportunity

OpenAIRE

Baruah, Bipasha

2010-01-01

This paper examines land tenure in informal urban settlements in India from a gender perspective through field research conducted in Ahmedabad in collaboration with the Self-Employed Women's Association (SEWA). The author describes the formal and informal tenure arrangements that were in place in these settlements and analyses their implications for women. She proceeds to raise key issues that need consideration in developing a gender-equitable vision of urban land rights, tenure and reform. ...

Does Audit Quality Improve After the Implementation of Mandatory Audit Partner Rotation?

OpenAIRE

Gary MONROE; Sarowar HOSSAIN

2013-01-01

We investigate whether audit partner tenure and audit quality associations remain significant after the implementation of mandatory audit partner rotation. Carey and Simnett (2006) report a significant negative association between long audit partner tenure and the propensity to issue qualified going-concern opinions for financially distressed companies. However, their study uses data from a period when there was no restriction on the length of audit partner tenure, i.e., from a period before ...

Varied appearance of lymphoma in patients with AIDS

International Nuclear Information System (INIS)

Sider, L.; Weiss, A.

1988-01-01

Lymphoma is frequently present in patients with acquired immunodeficiency (AIDS). But unlike in the general population, the appearance of lymphoma in patients with AIDS is extremely varied. The computed tomographic scans, chest radiographs, and subsequent hospital courses of 15 patients with AIDS-related lymphoma are presented. The patients presented with isolated pleural effusion (six patients), pleural and pericardial effusion (one patient), pulmonary infiltrates (five patients), and mediastinal adenopathy (three patients). This varied manner of presentation of lymphoma in AIDS patients should be recognized if diagnosis is to be made in the earlier stages of presentation

Compilation of Instantaneous Source Functions for Varying ...

African Journals Online (AJOL)

Compilation of Instantaneous Source Functions for Varying Architecture of a Layered Reservoir with Mixed Boundaries and Horizontal Well Completion Part III: B-Shaped Architecture with Vertical Well in the Upper Layer.

Varying hemin concentrations affect Porphyromonas gingivalis strains differently.

Science.gov (United States)

Ohya, Manabu; Cueno, Marni E; Tamura, Muneaki; Ochiai, Kuniyasu

2016-05-01

Porphyromonas gingivalis requires heme to grow, however, heme availability and concentration in the periodontal pockets vary. Fluctuations in heme concentration may affect each P. gingivalis strain differently, however, this was never fully demonstrated. Here, we elucidated the effects of varying hemin concentrations in representative P. gingivalis strains. Throughout this study, representative P. gingivalis strains [FDC381 (type I), MPWIb-01 (type Ib), TDC60 (type II), ATCC49417 (type III), W83 (type IV), and HNA99 (type V)] were used and grown for 24 h in growth media under varying hemin concentrations (5 × , 1 × , 0.5 × , 0.1 × ). Samples were lysed and protein standardized. Arg-gingipain (Rgp), H2O2, and superoxide dismutase (SOD) levels were subsequently measured. We focused our study on 24 h-grown strains which excluded MPWIb-01 and HNA99. Rgp activity among the 4 remaining strains varied with Rgp peaking at: 1 × for FDC381, 5 × for TDC60, 0.5 × for ATCC49417, 5 × and 0.5 × for W83. With regards to H2O2 and SOD amounts: FDC381 had similar H2O2 amounts in all hemin concentrations while SOD levels varied; TDC60 had the lowest H2O2 amount at 1 × while SOD levels became higher in relation to hemin concentration; ATCC49417 also had similar H2O2 amounts in all hemin concentrations while SOD levels were higher at 1 × and 0.5 × ; and W83 had statistically similar H2O2 and SOD amounts regardless of hemin concentration. Our results show that variations in hemin concentration affect each P. gingivalis strain differently. Published by Elsevier Ltd.

CERAMIC WASTE FORM DATA PACKAGE

Energy Technology Data Exchange (ETDEWEB)

Amoroso, J.; Marra, J.

2014-06-13

The purpose of this data package is to provide information about simulated crystalline waste forms that can be used to select an appropriate composition for a Cold Crucible Induction Melter (CCIM) proof of principle demonstration. Melt processing, viscosity, electrical conductivity, and thermal analysis information was collected to assess the ability of two potential candidate ceramic compositions to be processed in the Idaho National Laboratory (INL) CCIM and to guide processing parameters for the CCIM operation. Given uncertainties in the CCIM capabilities to reach certain temperatures throughout the system, one waste form designated 'Fe-MP' was designed towards enabling processing and another, designated 'CAF-5%TM-MP' was designed towards optimized microstructure. Melt processing studies confirmed both compositions could be poured from a crucible at 1600{degrees}C although the CAF-5%TM-MP composition froze before pouring was complete due to rapid crystallization (upon cooling). X-ray diffraction measurements confirmed the crystalline nature and phase assemblages of the compositions. The kinetics of melting and crystallization appeared to vary significantly between the compositions. Impedance spectroscopy results indicated the electrical conductivity is acceptable with respect to processing in the CCIM. The success of processing either ceramic composition will depend on the thermal profiles throughout the CCIM. In particular, the working temperature of the pour spout relative to the bulk melter which can approach 1700{degrees}C. The Fe-MP composition is recommended to demonstrate proof of principle for crystalline simulated waste forms considering the current configuration of INL's CCIM. If proposed modifications to the CCIM can maintain a nominal temperature of 1600{degrees}C throughout the melter, drain, and pour spout, then the CAF-5%TM-MP composition should be considered for a proof of principle demonstration.

Identification of Time-Varying Pilot Control Behavior in Multi-Axis Control Tasks

Science.gov (United States)

Zaal, Peter M. T.; Sweet, Barbara T.

2012-01-01

Recent developments in fly-by-wire control architectures for rotorcraft have introduced new interest in the identification of time-varying pilot control behavior in multi-axis control tasks. In this paper a maximum likelihood estimation method is used to estimate the parameters of a pilot model with time-dependent sigmoid functions to characterize time-varying human control behavior. An experiment was performed by 9 general aviation pilots who had to perform a simultaneous roll and pitch control task with time-varying aircraft dynamics. In 8 different conditions, the axis containing the time-varying dynamics and the growth factor of the dynamics were varied, allowing for an analysis of the performance of the estimation method when estimating time-dependent parameter functions. In addition, a detailed analysis of pilots adaptation to the time-varying aircraft dynamics in both the roll and pitch axes could be performed. Pilot control behavior in both axes was significantly affected by the time-varying aircraft dynamics in roll and pitch, and by the growth factor. The main effect was found in the axis that contained the time-varying dynamics. However, pilot control behavior also changed over time in the axis not containing the time-varying aircraft dynamics. This indicates that some cross coupling exists in the perception and control processes between the roll and pitch axes.

Spatially varying dispersion to model breakthrough curves.

Science.gov (United States)

Li, Guangquan

2011-01-01

Often the water flowing in a karst conduit is a combination of contaminated water entering at a sinkhole and cleaner water released from the limestone matrix. Transport processes in the conduit are controlled by advection, mixing (dilution and dispersion), and retention-release. In this article, a karst transport model considering advection, spatially varying dispersion, and dilution (from matrix seepage) is developed. Two approximate Green's functions are obtained using transformation of variables, respectively, for the initial-value problem and for the boundary-value problem. A numerical example illustrates that mixing associated with strong spatially varying conduit dispersion can cause strong skewness and long tailing in spring breakthrough curves. Comparison of the predicted breakthrough curve against that measured from a dye-tracing experiment between Ames Sink and Indian Spring, Northwest Florida, shows that the conduit dispersivity can be as large as 400 m. Such a large number is believed to imply strong solute interaction between the conduit and the matrix and/or multiple flow paths in a conduit network. It is concluded that Taylor dispersion is not dominant in transport in a karst conduit, and the complicated retention-release process between mobile- and immobile waters may be described by strong spatially varying conduit dispersion. Copyright © 2010 The Author(s). Journal compilation © 2010 National Ground Water Association.

The structure of a three-dimensional boundary layer subjected to streamwise-varying spanwise-homogeneous pressure gradient

International Nuclear Information System (INIS)

Bentaleb, Y.; Leschziner, M.A.

2013-01-01

Highlights: • We study a spatially-evolving three-dimensional boundary layer. • We impose a streamwise-varying spanwise-homogeneous pressure gradient. • A collateral flow is formed close to the wall, and this is investigated alongside the skewed upper part of the boundary layer. • A wide range of flow-physical properties have been studied. -- Abstract: A spatially-evolving three-dimensional boundary layer, subjected to a streamwise-varying spanwise-homogeneous pressure gradient, equivalent to a body force, is investigated by way of direct numerical simulation. The pressure gradient, prescribed to change its sign half-way along the boundary layer, provokes strong skewing of the velocity vector, with a layer of nearly collateral flow forming close to the wall up to the position of maximum spanwise velocity. A wide range of flow-physical properties have been studied, with particular emphasis on the near-wall layer, including second-moments, major budget contributions and wall-normal two-point correlations of velocity fluctuations and their angles, relative to wall-shear fluctuations. The results illustrate the complexity caused by skewing, including a damping in turbulent mixing and a significant lag between strains and stresses. The study has been undertaken in the context of efforts to develop and test novel hybrid LES–RANS schemes for non-equilibrium near-wall flows, with an emphasis on three-dimensional near-wall straining. Fundamental flow-physical issues aside, the data derived should be of particular relevance to a priori studies of second-moment RANS closure and the development and validation of RANS-type near-wall approximations implemented in LES schemes for high-Reynolds-number complex flows

Relativistic form factors for hadrons with quark-model wave functions

International Nuclear Information System (INIS)

Stanley, D.P.; Robson, D.

1982-01-01

The relationship between relativistic form factors and quark-potential-model wave functions is examined using an improved version of an approach by Licht and Pagnamenta. Lorentz-contraction effects are expressed in terms of an effective hadron mass which varies as the square root of the number of quark constituents. The effective mass is calculated using the rest-frame wave functions from the mean-square momentum along the direction of the momentum transfer. Applications with the parameter-free approach are made to the elastic form factors of the pion, proton, and neutron using a Hamiltonian which simultaneously describes mesons and baryons. A comparison of the calculated radii for pions and kaons suggests that the measured kaon radius should be slightly smaller than the corresponding pion radius. The large negative squared charge radius for the neutron is partially explained via the quark model but a full description requires the inclusion of a small component of a pion ''cloud'' configuration. The problematic connection between the sizes of hadrons deduced from form factors and the ''measured'' values of average transverse momenta is reconciled in the present model

Regional scenario building as a tool to support vulnerability assessment of food & water security and livelihood conditions under varying natural resources managements

Science.gov (United States)

Reinhardt, Julia; Liersch, Stefan; Dickens, Chris; Kabaseke, Clovis; Mulugeta Lemenih, Kassaye; Sghaier, Mongi; Hattermann, Fred

2013-04-01

state and availability of natural resources. Major concerns in all CS are the fast growing populations and natural resources degradation because of unsustainable natural resource management. Land use and resource competition are a consequence of unclear land tenure systems and limited resources availability. Scarce rainfall with high annual variability causes food insecurity if yield failures cannot be compensated, e.g. because of lacking financial resources. In all case studies critical uncertainties were identified to be more or less related to "poor governance". Missing governmental and political stability and effectiveness as well as corruption hamper the implementation of laws and policies related to natural resource management. Other critical uncertainties lie in the social domain. They are either related to demographic patterns like emigration or immigration varying the pressure on natural resources use or to the society in general like the evolvement of people's environmental awareness or voice and accountability. Methodological outcomes of the scenario building were that the complexity of the process requires the use of reliable and powerful tools to support the communication process. Concept maps were found to be a useful tool in this regard.

Testing for time-varying loadings in dynamic factor models

DEFF Research Database (Denmark)

Mikkelsen, Jakob Guldbæk

Abstract: In this paper we develop a test for time-varying factor loadings in factor models. The test is simple to compute and is constructed from estimated factors and residuals using the principal components estimator. The hypothesis is tested by regressing the squared residuals on the squared...... there is evidence of time-varying loadings on the risk factors underlying portfolio returns for around 80% of the portfolios....

VariVis: a visualisation toolkit for variation databases

Directory of Open Access Journals (Sweden)

Smith Timothy D

2008-04-01

Full Text Available Abstract Background With the completion of the Human Genome Project and recent advancements in mutation detection technologies, the volume of data available on genetic variations has risen considerably. These data are stored in online variation databases and provide important clues to the cause of diseases and potential side effects or resistance to drugs. However, the data presentation techniques employed by most of these databases make them difficult to use and understand. Results Here we present a visualisation toolkit that can be employed by online variation databases to generate graphical models of gene sequence with corresponding variations and their consequences. The VariVis software package can run on any web server capable of executing Perl CGI scripts and can interface with numerous Database Management Systems and "flat-file" data files. VariVis produces two easily understandable graphical depictions of any gene sequence and matches these with variant data. While developed with the goal of improving the utility of human variation databases, the VariVis package can be used in any variation database to enhance utilisation of, and access to, critical information.

New varying speed of light theories

International Nuclear Information System (INIS)

Magueijo, Joao

2003-01-01

We review recent work on the possibility of a varying speed of light (VSL). We start by discussing the physical meaning of a varying-c, dispelling the myth that the constancy of c is a matter of logical consistency. We then summarize the main VSL mechanisms proposed so far: hard breaking of Lorentz invariance; bimetric theories (where the speeds of gravity and light are not the same); locally Lorentz invariant VSL theories; theories exhibiting a colour-dependent speed of light; varying-c induced by extra dimensions (e.g. in the brane-world scenario); and field theories where VSL results from vacuum polarization or CPT violation. We show how VSL scenarios may solve the cosmological problems usually tackled by inflation, and also how they may produce a scale-invariant spectrum of Gaussian fluctuations, capable of explaining the WMAP data. We then review the connection between VSL and theories of quantum gravity, showing how 'doubly special' relativity has emerged as a VSL effective model of quantum space-time, with observational implications for ultra-high energy cosmic rays (UHECRs) and gamma ray bursts. Some recent work on the physics of 'black' holes and other compact objects in VSL theories is also described, highlighting phenomena associated with spatial (as opposed to temporal) variations in c. Finally, we describe the observational status of the theory. The evidence is currently slim-redshift dependence in the atomic fine structure, anomalies with UHECRs, and (to a much lesser extent) the acceleration of the universe and the WMAP data. The constraints (e.g. those arising from nucleosynthesis or geological bounds) are tight but not insurmountable. We conclude with the observational predictions of the theory and the prospects for its refutation or vindication

Fractionation of Uranium Forms as Affected by Spiked Soil Treatment and Soil Type

International Nuclear Information System (INIS)

Lotfy, S.M.; Mostafa, A.Z.; Abdel-Sabour, M.F.

2012-01-01

In a fractionation experiment Uranium forms were compared in two soil types (Mostorud and Elgabalelasfar soil). Also, the variation of U forms due to soil treatment (spiking) were studied. In case of Mostorud soil the initial U - fractions were 45.63 % as residual form, 20.69 % organically bound 16.36 % Mn and Fe oxides bound, 9.76% Carbonate form, 7.41 % exchangeable fractions and 0.15% water soluble fractions. These fractions varied significantly when the soil was spiked with 200 mg U/Kg soil to 46.88 %, 23.19 %, 9.97 %, 16.07 %, 3.79% and 0.10% for residual, organically, Mn- Fe oxide, carbonate, exchangeable and water soluble fractions respectively. These result showed significant reduction in U-ex fraction forms and Mn- Fe bound forms with significant increase in U- carbonate form due to U application. In case of Elgabalelasfar soil, the main U - fractions were 57.42% as residual form (relatively higher residual - U form in the clayey soil) 16.10 % organically bound, 13.78% Mn and Fe oxides bound, 7.22 % Carbonate form, 5.23 % exchangeable fractions and 0.25 % water soluble fractions The application of 200 mg U/Kg soil resulted in a significant changes in U - Fractions distribution as follows : 59.26 % , 11.27 % , 19.59 % , 6.84 % , 2.90 % and 0.14 % for residual , organic , Mn- Fe oxides , carbonate, exchangeable and water soluble fractions , respectively.

Varying prior information in Bayesian inversion

International Nuclear Information System (INIS)

Walker, Matthew; Curtis, Andrew

2014-01-01

Bayes' rule is used to combine likelihood and prior probability distributions. The former represents knowledge derived from new data, the latter represents pre-existing knowledge; the Bayesian combination is the so-called posterior distribution, representing the resultant new state of knowledge. While varying the likelihood due to differing data observations is common, there are also situations where the prior distribution must be changed or replaced repeatedly. For example, in mixture density neural network (MDN) inversion, using current methods the neural network employed for inversion needs to be retrained every time prior information changes. We develop a method of prior replacement to vary the prior without re-training the network. Thus the efficiency of MDN inversions can be increased, typically by orders of magnitude when applied to geophysical problems. We demonstrate this for the inversion of seismic attributes in a synthetic subsurface geological reservoir model. We also present results which suggest that prior replacement can be used to control the statistical properties (such as variance) of the final estimate of the posterior in more general (e.g., Monte Carlo based) inverse problem solutions. (paper)

Robust Stability and H∞ Stabilization of Switched Systems with Time-Varying Delays Using Delta Operator Approach

Directory of Open Access Journals (Sweden)

Chen Qin

2013-01-01

Full Text Available This paper considers the problems of the robust stability and robust H∞ controller design for time-varying delay switched systems using delta operator approach. Based on the average dwell time approach and delta operator theory, a sufficient condition of the robust exponential stability is presented by choosing an appropriate Lyapunov-Krasovskii functional candidate. Then, a state feedback controller is designed such that the resulting closed-loop system is exponentially stable with a guaranteed H∞ performance. The obtained results are formulated in the form of linear matrix inequalities (LMIs. Finally, a numerical example is provided to explicitly illustrate the feasibility and effectiveness of the proposed method.

Time-varying properties of renal autoregulatory mechanisms

DEFF Research Database (Denmark)

Zou, Rui; Cupples, Will A; Yip, K P

2002-01-01

In order to assess the possible time-varying properties of renal autoregulation, time-frequency and time-scaling methods were applied to renal blood flow under broad-band forced arterial blood pressure fluctuations and single-nephron renal blood flow with spontaneous oscillations obtained from...... normotensive (Sprague-Dawley, Wistar, and Long-Evans) rats, and spontaneously hypertensive rats. Time-frequency analyses of normotensive and hypertensive blood flow data obtained from either the whole kidney or the single-nephron show that indeed both the myogenic and tubuloglomerular feedback (TGF) mechanisms...... have time-varying characteristics. Furthermore, we utilized the Renyi entropy to measure the complexity of blood-flow dynamics in the time-frequency plane in an effort to discern differences between normotensive and hypertensive recordings. We found a clear difference in Renyi entropy between...

Non-minimally coupled varying constants quantum cosmologies

International Nuclear Information System (INIS)

Balcerzak, Adam

2015-01-01

We consider gravity theory with varying speed of light and varying gravitational constant. Both constants are represented by non-minimally coupled scalar fields. We examine the cosmological evolution in the near curvature singularity regime. We find that at the curvature singularity the speed of light goes to infinity while the gravitational constant vanishes. This corresponds to the Newton's Mechanics limit represented by one of the vertex of the Bronshtein-Zelmanov-Okun cube [1,2]. The cosmological evolution includes both the pre-big-bang and post-big-bang phases separated by the curvature singularity. We also investigate the quantum counterpart of the considered theory and find the probability of transition of the universe from the collapsing pre-big-bang phase to the expanding post-big-bang phase

Television viewing and forms of bullying among adolescents from eight countries.

Science.gov (United States)

Kuntsche, Emmanuel; Pickett, William; Overpeck, Mary; Craig, Wendy; Boyce, William; de Matos, Margarida Gaspar

2006-12-01

Based on theories suggesting that frequent television viewers act and react in hostile, malicious, malevolent, or verbally aggressive ways rather than being physically violent, the present study investigates relationships between television viewing and different forms of bullying. Multilevel regression models were estimated based on cross-sectional data from 31,177 adolescents aged 11, 13, and 15 years from Canada, Estonia, Israel, Latvia, Macedonia, Poland, Portugal, and the United States who participated in the 2001-2002 Health Behavior in School-aged Children Survey. Although all different forms of bullying were associated with television viewing in bivariate analyses, only the verbal forms (i.e. "calling mean names" and "spreading rumors") remained significant in multiple regression models. These relationships were observed consistently in all eight participating countries. However, the association between television viewing and physical forms of bullying such as kicking, pushing, or shoving around, varied across countries. In most weekend TV viewing cultures, frequent television viewers were prone to kick or push another student in addition to verbal forms of bullying, which was not the case in weekday viewing cultures. These results demonstrate the importance of limiting adolescents' time engaged in unsupervised television watching, and the need to motivate adolescents to engage in joint family activities or organized after-school activities.

Do Time-Varying Covariances, Volatility Comovement and Spillover Matter?

OpenAIRE

Lakshmi Balasubramanyan

2005-01-01

Financial markets and their respective assets are so intertwined; analyzing any single market in isolation ignores important information. We investigate whether time varying volatility comovement and spillover impact the true variance-covariance matrix under a time-varying correlation set up. Statistically significant volatility spillover and comovement between US, UK and Japan is found. To demonstrate the importance of modelling volatility comovement and spillover, we look at a simple portfo...

Turbulence characteristics of flow in an open channel with temporally varying mobile bedforms

Directory of Open Access Journals (Sweden)

Hanmaiahgari Prashanth Reddy

2017-03-01

Full Text Available Turbulence of flow over mobile bedforms in natural open channels is not yet clearly understood. An attempt is made in this paper to determine the effect of naturally formed mobile bedforms on velocities, turbulent intensities and turbulent stresses. Instantaneous velocities are measured using a two-dimensional particle image velocimetry (PIV to evaluate the turbulence structure of free surface flow over a fixed (immobile bed, a weakly mobile bed and a temporally varying mobile bed with different stages of bedform development. This paper documents the vertical distribution of velocity, turbulence intensities, Reynolds shear stress and higher-order moments including skewness and turbulent diffusion factors. Analysis of the velocity distributions shows a substantial decrease of velocity near the bed with increasing bedform mobility due to increased friction. A modified logarithmic law with a reduced von Kármán constant and increased velocity shift is proposed for the case of the mobile bedforms. A significant increase in the Reynolds shear stress is observed in the mobile bedforms experiments accompanied by changes over the entire flow depth compared to an immobile bed. The skewness factor distribution was found to be different in the case of the flow over the mobile bedforms. All higher-order turbulence descriptors are found to be significantly affected by the formation of temporally varying and non-equilibrium mobile bedforms. Quadrant analysis indicates that sweep and outward events are found to be dominant in strongly mobile bedforms and govern the bedform mobility.

Robust Stabilization of Nonlinear Systems with Uncertain Varying Control Coefficient

Directory of Open Access Journals (Sweden)

Zaiyue Yang

2014-01-01

Full Text Available This paper investigates the stabilization problem for a class of nonlinear systems, whose control coefficient is uncertain and varies continuously in value and sign. The study emphasizes the development of a robust control that consists of a modified Nussbaum function to tackle the uncertain varying control coefficient. By such a method, the finite-time escape phenomenon has been prevented when the control coefficient is crossing zero and varying its sign. The proposed control guarantees the asymptotic stabilization of the system and boundedness of all closed-loop signals. The control performance is illustrated by a numerical simulation.

Varying ultrasound power level to distinguish surgical instruments and tissue.

Science.gov (United States)

Ren, Hongliang; Anuraj, Banani; Dupont, Pierre E

2018-03-01

We investigate a new framework of surgical instrument detection based on power-varying ultrasound images with simple and efficient pixel-wise intensity processing. Without using complicated feature extraction methods, we identified the instrument with an estimated optimal power level and by comparing pixel values of varying transducer power level images. The proposed framework exploits the physics of ultrasound imaging system by varying the transducer power level to effectively distinguish metallic surgical instruments from tissue. This power-varying image-guidance is motivated from our observations that ultrasound imaging at different power levels exhibit different contrast enhancement capabilities between tissue and instruments in ultrasound-guided robotic beating-heart surgery. Using lower transducer power levels (ranging from 40 to 75% of the rated lowest ultrasound power levels of the two tested ultrasound scanners) can effectively suppress the strong imaging artifacts from metallic instruments and thus, can be utilized together with the images from normal transducer power levels to enhance the separability between instrument and tissue, improving intraoperative instrument tracking accuracy from the acquired noisy ultrasound volumetric images. We performed experiments in phantoms and ex vivo hearts in water tank environments. The proposed multi-level power-varying ultrasound imaging approach can identify robotic instruments of high acoustic impedance from low-signal-to-noise-ratio ultrasound images by power adjustments.

One-dimensional free-electron laser equations without the slowly varying envelope approximation

Directory of Open Access Journals (Sweden)

C. Maroli

2011-07-01

Full Text Available A set of one-dimensional equations has been deduced in the time domain from the Maxwell-Lorentz system with the aim of describing the free-electron laser radiation without using the slowly varying envelope approximation (SVEA. These equations are valid even in the case of arbitrarily short electron bunches and of current distributions with ripples on the scale of or shorter than the wavelength. Numerical examples are presented, showing that for long homogeneous bunches the new set of equations gives results in agreement with the SVEA free-electron laser theory and that the use of short or prebunched electron beams leads to a decrease of the emission lethargy. Furthermore, we demonstrate that in all cases in which the backward low frequency wave has negligible effects, these equations can be reduced to a form similar to the usual 1D SVEA equations but with a different definition of the bunching term.

L'urbain trans-formé par Internet et les TIC

OpenAIRE

Carmes, Maryse; Noyer, Jean-Max; Rigal, Alexandre

2014-01-01

On découvre en pensant leurs pratiques dans l'espace urbain que les Technologies de l'Information et de la Communication sont probablement mal nommées. Il n'y aurait pas de mise en forme unilatérale et fixe, d'information, mais bien des trans-formations des acteurs et des pratiques des outils entre eux, en particulier par la communication. De la prise en compte de ces pratiques variées, des mélanges de codages spatiaux et digitaux qui s'inter-relient en certains acteurs, en certains lieux et ...

Violence in primary schools in Serbia: Forms and prevalence

Directory of Open Access Journals (Sweden)

Popadić Dragan

2007-01-01

Full Text Available A questionnaire study of 26,228 pupils of grades 3 through 8 in 50 primary schools across Serbia, conducted in spring 2006, indicated that in a three-month period, 65.3% of the pupils stated that they experienced some form of peer violence (the percentage varies by school, between 48% and 80%. An analysis of repeated violence cases identifies 20.7% of the pupils as victims, 3.8% as perpetrators of violence, and 3.6% as victims/perpetrators. Adult violence is reported by 35.7% of the pupils, while 42% have witnessed verbal aggression of pupils towards teachers. The most frequent forms of peer violence reported were insults (45.6% and plotting (32.6%. Boys declared themselves as perpetrators of violence somewhat more frequently than girls, and they were somewhat more often exposed to peer and adult violence. Older pupils were more frequently violent and more often reported adult violence, while age differences in exposure to violence were minimal. .

Optimal lipofection reagent varies with the molecular modifications of the DNA.

Science.gov (United States)

Conrad, A H; Behlke, M A; Jaffredo, T; Conrad, G W

1998-10-01

Cationic lipid reagents differ in their cytofection efficacy with different cell types. No evidence has addressed whether the same lipid reagent is best for different DNAs in a single cell line. Immortalized avian embryonic cardiomyocytes cultured in vitro were tested with 15 cationic lipid reagents using (A) a beta-gal expression plasmid, (B) a fluorescein-tagged, phosphorothioate-modified ODN B, (C) a fluorescein-tagged, ethoxy-modified ODN C with the same nucleotide sequence as ODN B, and (D) a fluorescein-tagged, phosphorothioate-modified ODN D with a different nucleotide sequence from ODNs B and C. Cytofection was scored as percent of cells expressing beta-gal activity or showing diffuse cellular fluorescence. The best lipid reagents for the phosphorothioate-modified ODNs were ODN-specific and markedly different from the best lipid reagents for the expression plasmid or for the ethoxy-modified ODN. These results suggest that the best cationic lipid reagent for a particular cell type varies with the physical and chemical form of the DNA being transfected into the cells.

The estimation of time-varying risks in asset pricing modelling using B-Spline method

Science.gov (United States)

Nurjannah; Solimun; Rinaldo, Adji

2017-12-01

Asset pricing modelling has been extensively studied in the past few decades to explore the risk-return relationship. The asset pricing literature typically assumed a static risk-return relationship. However, several studies found few anomalies in the asset pricing modelling which captured the presence of the risk instability. The dynamic model is proposed to offer a better model. The main problem highlighted in the dynamic model literature is that the set of conditioning information is unobservable and therefore some assumptions have to be made. Hence, the estimation requires additional assumptions about the dynamics of risk. To overcome this problem, the nonparametric estimators can also be used as an alternative for estimating risk. The flexibility of the nonparametric setting avoids the problem of misspecification derived from selecting a functional form. This paper investigates the estimation of time-varying asset pricing model using B-Spline, as one of nonparametric approach. The advantages of spline method is its computational speed and simplicity, as well as the clarity of controlling curvature directly. The three popular asset pricing models will be investigated namely CAPM (Capital Asset Pricing Model), Fama-French 3-factors model and Carhart 4-factors model. The results suggest that the estimated risks are time-varying and not stable overtime which confirms the risk instability anomaly. The results is more pronounced in Carhart’s 4-factors model.

Skin friction measurements of systematically-varied roughness: Probing the role of roughness amplitude and skewness

Science.gov (United States)

Barros, Julio; Flack, Karen; Schultz, Michael

2017-11-01

Real-world engineering systems which feature either external or internal wall-bounded turbulent flow are routinely affected by surface roughness. This gives rise to performance degradation in the form of increased drag or head loss. However, at present there is no reliable means to predict these performance losses based upon the roughness topography alone. This work takes a systematic approach by generating random surface roughness in which the surface statistics are closely controlled. Skin friction and roughness function results will be presented for two groups of these rough surfaces. The first group is Gaussian (i.e. zero skewness) in which the root-mean-square roughness height (krms) is varied. The second group has a fixed krms, and the skewness is varied from approximately -1 to +1. The effect of the roughness amplitude and skewness on the skin friction will be discussed. Particular attention will be paid to the effect of these parameters on the roughness function in the transitionally-rough flow regime. For example, the role these parameters play in the monotonic or inflectional nature of the roughness function will be addressed. Future research into the details of the turbulence structure over these rough surfaces will also be outlined. Research funded by U.S. Office of Naval Research (ONR).

Bounds and asymptotics for orthogonal polynomials for varying weights

CERN Document Server

Levin, Eli

2018-01-01

This book establishes bounds and asymptotics under almost minimal conditions on the varying weights, and applies them to universality limits and entropy integrals.  Orthogonal polynomials associated with varying weights play a key role in analyzing random matrices and other topics.  This book will be of use to a wide community of mathematicians, physicists, and statisticians dealing with techniques of potential theory, orthogonal polynomials, approximation theory, as well as random matrices. .

Response of rabbits to varying levels of cassava and Leucaena ...

African Journals Online (AJOL)

Response of rabbits to varying levels of cassava and Leucaena leucocephala leaf meal diets. ... Bulletin of Animal Health and Production in Africa ... An experiment was carried out to determine the performance, haematology, carcass characteristics and sensory evaluation of meat from rabbits (n = 30) fed varying levels of ...

The Thermal Collector With Varied Glass Covers

International Nuclear Information System (INIS)

Luminosu, I.; Pop, N.

2010-01-01

The thermal collector with varied glass covers represents an innovation realized in order to build a collector able to reach the desired temperature by collecting the solar radiation from the smallest surface, with the highest efficiency. In the case of the thermal collector with variable cover glasses, the number of the glass plates covering the absorber increases together with the length of the circulation pipe for the working fluid. The thermal collector with varied glass covers compared to the conventional collector better meet user requirements because: for the same temperature increase, has the collecting area smaller; for the same collection area, realizes the highest temperature increase and has the highest efficiency. This works is addressed to researchers in the solar energy and to engineers responsible with air-conditioning systems design or industrial and agricultural products drying.

Electron spin resonance and thermoluminescence in powder form of clear fused quartz: effects of grinding

International Nuclear Information System (INIS)

Ranjbar, A.H.; Durrani, S.A.; Randle, K.

1999-01-01

Clear fused quartz (CFQ) tubes were powdered either manually by using a mortar and pestle (for coarse production) or mechanically, using a micronising mill (for fine production). A high and multisignal electron spin resonance (ESR) background was found in the fine powder even after annealing it at 900 deg. C for 20 min. In the case of the coarse powder, the signal (ESR background) varied inversely with particle size and was quite high for particle sizes lower than 38 μm. In a subsidiary experiment, using fine SiO 2 powder (99.8% pure, with the particle size of ∼0.007 μm), manufactured by using flame hydrolysis, only a weak background signal was found. The 60 Co gamma-ray irradiated powders (∼22 Gy) were subjected to ESR analysis or thermoluminescence (TL) readout. The ESR intensity of the coarse powder varied directly with particle size. Thus, the intensity for a particle size of 20-38 μm was very low and almost the same as the unirradiated intensity. In TL readout the results were the opposite: the TL intensity of the coarse powder varied inversely with the particle size down to 38 μm, after which it decreased with decreasing particle size of the material. The fine powder, produced by grinding the CFQ tubes, was insensitive to gamma-rays (at least at doses of up to 50 Gy); but for the flame hydrolysis SiO 2 the situation was the opposite. The minimum detectable dose (MDD) for the CFQ in powder form using ESR was ∼2 Gy, which is ∼2 times higher than that for the bulk form, while the MDD for the powder using TL was ∼20 μGy, which is ∼2 times lower than that for the bulk form of the material

Electron spin resonance and thermoluminescence in powder form of clear fused quartz: effects of grinding

Energy Technology Data Exchange (ETDEWEB)

Ranjbar, A.H. [Physics Department, Shahid Bahonar University of Kerman, Kerman (Iran, Islamic Republic of); Durrani, S.A. [School of Physics and Space Research, University of Birmingham, Birmingham (United Kingdom); Randle, K. [School of Chemistry, University of Birmingham, Birmingham (United Kingdom)

1999-02-01

Clear fused quartz (CFQ) tubes were powdered either manually by using a mortar and pestle (for coarse production) or mechanically, using a micronising mill (for fine production). A high and multisignal electron spin resonance (ESR) background was found in the fine powder even after annealing it at 900 deg. C for 20 min. In the case of the coarse powder, the signal (ESR background) varied inversely with particle size and was quite high for particle sizes lower than 38 {mu}m. In a subsidiary experiment, using fine SiO{sub 2} powder (99.8% pure, with the particle size of {approx}0.007 {mu}m), manufactured by using flame hydrolysis, only a weak background signal was found. The {sup 60}Co gamma-ray irradiated powders ({approx}22 Gy) were subjected to ESR analysis or thermoluminescence (TL) readout. The ESR intensity of the coarse powder varied directly with particle size. Thus, the intensity for a particle size of 20-38 {mu}m was very low and almost the same as the unirradiated intensity. In TL readout the results were the opposite: the TL intensity of the coarse powder varied inversely with the particle size down to 38 {mu}m, after which it decreased with decreasing particle size of the material. The fine powder, produced by grinding the CFQ tubes, was insensitive to gamma-rays (at least at doses of up to 50 Gy); but for the flame hydrolysis SiO{sub 2} the situation was the opposite. The minimum detectable dose (MDD) for the CFQ in powder form using ESR was {approx}2 Gy, which is {approx}2 times higher than that for the bulk form, while the MDD for the powder using TL was {approx}20 {mu}Gy, which is {approx}2 times lower than that for the bulk form of the material.

Secular trends in the geologic record and the supercontinent cycle

Science.gov (United States)

Bradley, Dwight C.

2011-01-01

Geologic secular trends are used to refine the timetable of supercontinent assembly, tenure, and breakup. The analysis rests on what is meant by the term supercontinent, which here is defined broadly as a grouping of formerly dispersed continents. To avoid the artificial pitfall of an all-or-nothing definition, quantitative measures of “supercontinentality” are presented: the number of continents, and the area of the largest continent, which both can be gleaned from global paleogeographic maps for the Phanerozoic. For the secular trends approach to be viable in the deep past when the very existence of supercontinents is debatable and reconstructions are fraught with problems, it must first be calibrated in the Phanerozoic against the well-constrained Pangea supercontinent cycle. The most informative geologic variables covering both the Phanerozoic and Precambrian are the abundances of passive margins and of detrital zircons. Both fluctuated with size of the largest continent during the Pangea supercontinent cycle and can be quantified back to the Neoarchean. The tenure of Pangea was a time represented in the rock record by few zircons and few passive margins. Thus, previously documented minima in the abundance of detrital zircons (and orogenic granites) during the Precambrian (Condie et al., 2009a, Gondwana Research 15, 228–242) now can be more confidently interpreted as marking the tenures of supercontinents. The occurrences of carbonatites, granulites, eclogites, and greenstone-belt deformation events also appear to bear the imprint of Precambrian supercontinent cyclicity. Together, these secular records are consistent with the following scenario. The Neoarchean continental assemblies of Superia and Sclavia broke up at ca. 2300 and ca. 2090 Ma, respectively. Some of their fragments collided to form Nuna by about 1750 Ma; Nuna then grew by lateral accretion of juvenile arcs during the Mesoproterozoic, and was involved in a series of collisions at ca. 1000 Ma

How Do Parenting Concepts Vary within and between the Families?

Science.gov (United States)

Roskam, Isabelle; Meunier, Jean Christophe

2009-01-01

How do parenting concepts vary within and between the families? The present study regards parenting as a complex family process by considering three concepts of parenting: styles, differential treatment and coparenting consistency. A main question was addressed: whether and how these parenting concepts vary within the families towards siblings or…

AdvanceVT Work/Life Policies : Summary Report

OpenAIRE

AdvanceVT

2010-01-01

AdvanceVT’s 2008 Faculty Work/Life Survey showed that 59% of tenured and tenure-track faculty members at Virginia Tech believe it is difficult to have a personal life and earn tenure and 48% feel that their family responsibilities have slowed their career advancement. Female faculty members indicated that they have considered leaving the university in order to obtain better career opportunities for their spouse or partner (43%), as well as to achieve a better personal/professional balance (50...

Social position and health in old age. The relevance of different indicators of social position

DEFF Research Database (Denmark)

Avlund, Kirsten; Holstein, Bjørn Evald; Osler, Merete

2002-01-01

Social medicine, social position, chronic diseases, material wealth, income, tenure, oral health, functional ability, well-being, mobility......Social medicine, social position, chronic diseases, material wealth, income, tenure, oral health, functional ability, well-being, mobility...

Performance of a solar chimney by varying design parameters

CSIR Research Space (South Africa)

Kumirai, T

2015-08-01

Full Text Available the design of solar chimneys to ensure optimal performance. The purpose of this chapter is to discuss the performance of an example solar chimney by varying the design parameters and examining their effects on the interior ventilation performance... chimney by varying design parameters Tichaona Kumirai, Researcher, Built Environment CSIR Jan-Hendrik Grobler, DPSS CSIR Dr D.C.U. Conradie, Senior researcher, Built Environment CSIR 1 Introduction Trombe walls and solar chimneys are not widely...

Modeling of Electricity Demand for Azerbaijan: Time-Varying Coefficient Cointegration Approach

Directory of Open Access Journals (Sweden)

Jeyhun I. Mikayilov

2017-11-01

Full Text Available Recent literature has shown that electricity demand elasticities may not be constant over time and this has investigated using time-varying estimation methods. As accurate modeling of electricity demand is very important in Azerbaijan, which is a transitional country facing significant change in its economic outlook, we analyze whether the response of electricity demand to income and price is varying over time in this economy. We employed the Time-Varying Coefficient cointegration approach, a cutting-edge time-varying estimation method. We find evidence that income elasticity demonstrates sizeable variation for the period of investigation ranging from 0.48% to 0.56%. The study has some useful policy implications related to the income and price aspects of the electricity consumption in Azerbaijan.

Modern Evaluation of Liquisolid Systems with Varying Amounts of Liquid Phase Prepared Using Two Different Methods

Directory of Open Access Journals (Sweden)

Barbora Vraníková

2015-01-01

Full Text Available Liquisolid systems are an innovative dosage form used for enhancing dissolution rate and improving in vivo bioavailability of poorly soluble drugs. These formulations require specific evaluation methods for their quality assurance (e.g., evaluation of angle of slide, contact angle, or water absorption ratio. The presented study is focused on the preparation, modern in vitro testing, and evaluation of differences of liquisolid systems containing varying amounts of a drug in liquid state (polyethylene glycol 400 solution of rosuvastatin in relation to an aluminometasilicate carrier (Neusilin US2. Liquisolid powders used for the formulation of final tablets were prepared using two different methods: simple blending and spraying of drug solution onto a carrier in fluid bed equipment. The obtained results imply that the amount of liquid phase in relation to carrier material had an effect on the hardness, friability, and disintegration of tablets, as well as their height. The use of spraying technique enhanced flow properties of the prepared mixtures, increased hardness values, decreased friability, and improved homogeneity of the final dosage form.

Plan demographics, participants' saving behavior, and target-date fund investments.

Science.gov (United States)

Park, Youngkyun

2009-05-01

This analysis explores (1) whether plan demographic characteristics would affect individual participant contribution rates and target-date fund investments and (2) equity glide paths for participants in relation to plan demographics by considering target replacement income and its success rate. PLAN DEMOGRAPHIC CHARACTERISTICS IN PARTICIPANT CONTRIBUTION RATES: This study finds empirical evidence that 401(k) plan participants' contribution rates differ by plan demographics based on participants' income and/or tenure. In particular, participants in 401(k) plans dominated by those with low income and short tenure tend to contribute less than those in plans dominated by participants with high income and long tenure. Future research will explore how participant contribution behavior may also be influenced by incentives provided by employers through matching formulae. PLAN DEMOGRAPHIC CHARACTERISTICS IN TARGET-DATE FUND INVESTMENTS: The study also finds empirical evidence that participants' investments in target-date funds with different equity allocations differ by plan demographics based on participants' income and/or tenure. In particular, target-date fund users with 90 percent or more of their account balances in target-date funds who are in 401(k) plans dominated by low-income and short-tenure participants tend to hold target-date funds with lower equity allocations, compared with their counterparts in plans dominated by high-income and long-tenure participants. Future research will focus on the extent to which these characteristics might influence the selection of target-date funds by plan sponsors. EQUITY GLIDE PATHS: Several stylized equity glide paths as well as alternative asset allocations are compared for participants at various starting ages to demonstrate the interaction between plan demographics and equity glide paths/asset allocations in terms of success rates in meeting various replacement income targets. The equity glide path/asset allocation providing

Sample size adjustments for varying cluster sizes in cluster randomized trials with binary outcomes analyzed with second-order PQL mixed logistic regression.

Science.gov (United States)

Candel, Math J J M; Van Breukelen, Gerard J P

2010-06-30

Adjustments of sample size formulas are given for varying cluster sizes in cluster randomized trials with a binary outcome when testing the treatment effect with mixed effects logistic regression using second-order penalized quasi-likelihood estimation (PQL). Starting from first-order marginal quasi-likelihood (MQL) estimation of the treatment effect, the asymptotic relative efficiency of unequal versus equal cluster sizes is derived. A Monte Carlo simulation study shows this asymptotic relative efficiency to be rather accurate for realistic sample sizes, when employing second-order PQL. An approximate, simpler formula is presented to estimate the efficiency loss due to varying cluster sizes when planning a trial. In many cases sampling 14 per cent more clusters is sufficient to repair the efficiency loss due to varying cluster sizes. Since current closed-form formulas for sample size calculation are based on first-order MQL, planning a trial also requires a conversion factor to obtain the variance of the second-order PQL estimator. In a second Monte Carlo study, this conversion factor turned out to be 1.25 at most. (c) 2010 John Wiley & Sons, Ltd.

RPA-mediated unfolding of systematically varying G-quadruplex structures.

Science.gov (United States)

Ray, Sujay; Qureshi, Mohammad H; Malcolm, Dominic W; Budhathoki, Jagat B; Celik, Uğur; Balci, Hamza

2013-05-21

G-quadruplex (GQ) is a noncanonical nucleic acid structure that is formed by guanine rich sequences. Unless it is destabilized by proteins such as replication protein A (RPA), GQ could interfere with DNA metabolic functions, such as replication or repair. We studied RPA-mediated GQ unfolding using single-molecule FRET on two groups of GQ structures that have different loop lengths and different numbers of G-tetrad layers. We observed a linear increase in the steady-state stability of the GQ against RPA-mediated unfolding with increasing number of layers or decreasing loop length. The stability demonstrated by different GQ structures varied by at least three orders of magnitude. Those with shorter loops (less than three nucleotides long) or a greater number of layers (more than three layers) maintained a significant folded population even at physiological RPA concentration (≈1 μM), raising the possibility of physiological viability of such GQ structures. Finally, we measured the transition time between the start and end of the RPA-mediated GQ unfolding process to be 0.35 ± 0.10 s for all GQ constructs we studied, despite significant differences in their steady-state stabilities. We propose a two-step RPA-mediated GQ unfolding mechanism that is consistent with our observations. Copyright © 2013 Biophysical Society. Published by Elsevier Inc. All rights reserved.

The Contribution of Io-Raised Tides to Europa's Diurnally-Varying Surface Stresses

Science.gov (United States)

Rhoden, Alyssa Rose; Hurford, Terry A,; Manga, Michael

2011-01-01

Europa's icy surface records a rich history of geologic activity, Several features appear to be tectonic in origin and may have formed in response to Europa's daily-varying tidal stress [I]. Strike-slip faults and arcuate features called cycloids have both been linked to the patterns of stress change caused by eccentricity and obliquity [2J[3]. In fact, as Europa's obliquity has not been directly measured, observed tectonic patterns arc currently the best indicators of a theoretically supported [4] non-negligible obliquity. The diurnal tidal stress due to eccentricity is calculated by subtracting the average (or static) tidal shape of Europa generated by Jupiter's gravitational field from the instantaneous shape, which varies as Europa moves through its eccentric orbit [5]. In other words, it is the change of shape away from average that generates tidal stress. One might expect tidal contributions from the other large moons of Jupiter to be negligible given their size and the height of the tides they raise on Europa versus Jupiter's mass and the height of the tide it raises on Europa, However, what matters for tidally-induced stress is not how large the lo-raised bulge is compared to the Jupiter-raised bulge but rather the differences bet\\Veen the instantaneous and static bulges in each case. For example, when Europa is at apocenter, Jupiter raises a tide 30m lower than its static tide. At the same time, 10 raises a tide about 0.5m higher than its static tide. Hence, the change in Io's tidal distortion is about 2% of the change in the Jovian distortion when Europa is at apocenter

Performance equations of proton exchange membrane fuel cells with feeds of varying degrees of humidification

International Nuclear Information System (INIS)

Hsuen, Hsiao-Kuo; Yin, Ken-Ming

2012-01-01

Performance equations that describe the dependence of cell potential on current density for proton exchange membrane fuel cells (PEMFCs) with feeds of varying degrees of humidification have been formulated in algebraic form. The equations are developed by the reduction of a one-dimensional multi-domain model that takes into account, in details, the transport limitations of gas species, proton migration and electron conduction, electrochemical kinetics, as well as liquid water flow within the cathode, anode, and membrane. The model equations for the anode and membrane were integrated with those of the cathode developed in the previous studies to form a complete set of equations for one-dimensional single cell model. Because the transport equations for the anode diffuser can be solved analytically, calculations of integrals are only needed in the membrane and the two-phase region of cathode diffuser. The proposed approach greatly reduces the complexity of the model equations, and only iterations of a single algebraic equation are required to obtain final solutions. Since the performance equations are originated from a mechanistic one-dimensional model, all the parameters appearing in the equations are endowed with a precise physical significance.

Studies on radiation damage to polystyrene exchanger in different cationic forms

International Nuclear Information System (INIS)

Dedgaonkar, V.G.; Jagtap, N.B.; Waghmare, S.; Kulkarni, S.A.

1985-01-01

Polystyrene divinylbenzene copolymer containing nuclear sulfonic acid functional group and H + , Sr 2+ , Cu 2+ , UO 2 2+ or Al 3+ exchangeable cation was subjected to varying gamma doses to study the effects on its physicochemical properties. The exchange capacity and moisture content decreased, the maximum effect was in the case of Cu ++ form of the resin. The data are explained on the basis of metal oxygen bonding. IR spectra indicated the formation of new exchange sites upon irradiation and disapearance of the original functional groups. (author)

Aging and the statistical learning of grammatical form classes.

Science.gov (United States)

Schwab, Jessica F; Schuler, Kathryn D; Stillman, Chelsea M; Newport, Elissa L; Howard, James H; Howard, Darlene V

2016-08-01

Language learners must place unfamiliar words into categories, often with few explicit indicators about when and how that word can be used grammatically. Reeder, Newport, and Aslin (2013) showed that college students can learn grammatical form classes from an artificial language by relying solely on distributional information (i.e., contextual cues in the input). Here, 2 experiments revealed that healthy older adults also show such statistical learning, though they are poorer than young at distinguishing grammatical from ungrammatical strings. This finding expands knowledge of which aspects of learning vary with aging, with potential implications for second language learning in late adulthood. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Stabilization of the Wave Equation with Boundary Time-Varying Delay

Directory of Open Access Journals (Sweden)

Hao Li

2014-01-01

Full Text Available We study the stabilization of the wave equation with variable coefficients in a bounded domain and a time-varying delay term in the time-varying, weakly nonlinear boundary feedbacks. By the Riemannian geometry methods and a suitable assumption of nonlinearity, we obtain the uniform decay of the energy of the closed loop system.

Semi-solid dosage form of clonazepam for rapid oral mucosal absorption.

Science.gov (United States)

Sakata, Osamu; Machida, Yoshiharu; Onishi, Hiraku

2011-07-01

In order to obtain an alternative to the intravenous (i.v.) dosage form of clonazepam (CZ), an oral droplet formulation of CZ was developed previously; however, the droplet was physically unstable. Therefore, in the present study, it was attempted to develop an easily-handled dosage form, which was more physically stable and allowed rapid drug absorption from oral mucosa. A semi-solid dosage form, composed of polyethylene glycol 1500 (PEG), CZ, and oleic acid (OA) at 37/1/2 (w/w) and named PEG/CZ/OA, and a semi-solid dosage form containing PEG and CZ at 39/1 (w/w), called PEG/CZ, were prepared. Their physical stability in air at room temperature and oral mucosal absorption in rats were investigated. The semi-solid dosage forms were much more stable physically than the droplet, that is, no recrystallization of CZ was observed for at least 8 days. The effective concentration for humans and rats (20 ng/mL or more) was achieved within 30 min after buccal administration for both PEG/CZ/OA and PEG/CZ. The plasma concentration increased gradually and less varied at each time point for PEG/CZ/OA. PEG/CZ/OA was found to show more rapid and higher absorption of CZ in buccal administration than in sublingual administration. Buccal administration with the semi-solid dosage PEG/CZ with or without OA was suggested to be a possibly useful novel dosage form as an alternative to i.v. injection.

Filmihullu eluvesi voolab Karlovy Varys / Margit Tõnson

Index Scriptorium Estoniae

Tõnson, Margit, 1978-

2010-01-01

Karlovy Vary rahvusvahelisest filmifestivalist. Filmidest "Mr. Nobody" (rež. Jaco Van Dormaeli), "Kasside ema Teresa" (rež. Pawel Sala) ja "The Arbor" (rež. Clio Barnardi). Nimekiri võitnud töödest ja viimastel aastatel festivalil näidatud Eesti mängufilmidest

Newtonian cosmology with a time-varying constant of gravitation

International Nuclear Information System (INIS)

McVittie, G.C.

1978-01-01

Newtonian cosmology is based on the Eulerian equations of fluid mechanics combined with Poisson's equation modified by the introduction of a time-varying G. Spherically symmetric model universes are worked out with instantaneously uniform densities. They are indeterminate unless instantaneous uniformity of the pressure is imposed. When G varies as an inverse power of the time, the models can in some cases be shown to depend on the solution of a second-order differential equation which also occurs in the Friedmann models of general relativity. In Section 3, a method for 'passing through' a singularity of this equation is proposed which entails making four arbitrary mathematical assumptions. When G varies as (time) -1 , models with initially cycloidal motion are possible, each cycle becoming longer as time progresses. Finally, gravitation becomes so weak that the model expands to infinity. Kinetic and potential energies for the whole model are derived from the basic equations; their sum is not constant. (author)