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Sample records for briggs criterion

  1. Credible Immigration Policy Reform: A Response to Briggs

    Science.gov (United States)

    Orrenius, Pia M.; Zavodny, Madeline

    2012-01-01

    The authors agree with Vernon M. Briggs, Jr., that U.S. immigration policy has had unexpected consequences. The 1965 immigration reforms led to unanticipated chain migration from developing countries whereas the 1986 Immigration Reform and Control Act failed to slow unauthorized immigration. The result is a large foreign-born population with…

  2. An Assessment of the Myers-Briggs Type Indicator

    Science.gov (United States)

    Carlyn, Marcia

    1977-01-01

    The Myers Briggs Type Indicator is a self-report inventory developed to measure variables in Carl Jung's personality typology. The four personality scales measured by the instrument, and the scoring process are described, and an extensive review of the intercorrelation, reliability, and validity research is presented. (Author/MV)

  3. ¿Quién es Malte Laurids Brigge?

    OpenAIRE

    Arroyo Redondo, Susana

    2008-01-01

    El artículo profundiza en los aspectos autobiográficos y las renovaciones formales de Los apuntes de Malte Laurids Brigge, de Rainer María Rilke, que más han influido en la creación del Yo novelístico contemporáneo.

  4. Myers-Briggs® Preferences and Academic Success in the First College Semester

    Science.gov (United States)

    Sanborn, Debra K.

    2013-01-01

    This research examined aspects of Myers-Briggs® preferences and academic success in the first college semester. Academic aptitude as measured by precollege characteristics of ACT and class rank, academic performance during the first semester of college, and Myers-Briggs preference were analyzed for their significance within a learning community at…

  5. Die Aufzeichnungen des Malte Laurids Brigge: novas perspectivas de interpretação

    OpenAIRE

    Renata Martins

    2012-01-01

    O objetivo deste texto é analisar a experiência do estranho no romance Die Aufzeichnungen des Malte Laurids Brigge, de Rainer Maria Rilke, através de novas perspectivas de interpretação apoiadas, por exemplo, nas teorias psicanalíticas de Sigmund Freud. Vivendo em uma cidade estrangeira (Paris), com a qual ainda não se identifica, o protagonista do romance, Malte Laurids Brigge, descobre um mundo interior novo através de seu choque com experiências do estranho nesse milieu. A revelação de rec...

  6. Utilizing the Myers-Briggs Personality Inventory in Employee Assistance Program Workplace Seminars.

    Science.gov (United States)

    Aviles, Christopher B.

    Social work educators are being called upon more often to deliver employee workplace seminars for community agencies on a variety of topics ranging from burnout and stress management to improving workplace communication and managing workplace conflicts. One tool that addresses workplace communication is the Myers-Briggs Type Indicator (MBTI). It…

  7. Personality Characteristics of South Korean Students with Visual Impairments Using the Myers-Briggs Type Indicator

    Science.gov (United States)

    Bak, Sunhi

    2012-01-01

    Introduction: The study presented here was designed to determine whether there were significant differences in the frequency and preference scores of personality functions and the frequency of personality types, as measured by the Myers-Briggs Type Indicator (MBTI), by gender, school level, and level of visual function, of students with visual…

  8. On Oswaldella billardi Briggs, 1938 and O. erratum spec, nov., two antarctic hydroid species (Cnidaria, Hydrozoa)

    NARCIS (Netherlands)

    Peña Cantero, A.L.; Vervoort, W.

    1997-01-01

    The type material of Oswaldella billardi Briggs, 1938, has been re-examined and a complete description and figures are presented. The study of that material has allowed to reconsider the systematic position of all the material previously assigned to O. billardi and to determine that part of it belon

  9. Myers-Briggs Attitude Typology: The Influence of Birth Order with Other Family Variables.

    Science.gov (United States)

    Stansbury, Virginia K.; Coll, Kenneth M.

    1998-01-01

    Investigates the influence of birth order with parenting style, age spacing, gender, and socioeconomic status on the Myers-Briggs attitude scales of Extroversion/Introversion and Judging/Perceiving. Results indicate that age spacing interacted with birth order to influence Extroversion/Introversion scores. Parenting style and gender interacted…

  10. The "imprisoned illness:" motor tic disorder in Rainer Maria Rilke's Notebooks of Malte Laurids Brigge.

    Science.gov (United States)

    Cavanna, Andrea Eugenio; Pattumelli, Maria Grazia; Quarto, Tiziana; Ali, Fizzah; Rickards, Hugh

    2010-09-15

    Rainer Maria Rilke's novel The Notebooks of Malte Laurids Brigge contains a reference of interest for the catalog of literary portrayals of tiqueurs. In this article, we report his description of a Parisian character displaying multiple motor tic symptoms, along with a brief commentary. PMID:20669278

  11. The Myers-Briggs Type Indicator and the Teaching-Learning Process.

    Science.gov (United States)

    McCaulley, Mary H.

    The Myers-Briggs Type Indicator (MBTI) was developed specifically to make possible the implementation of Carl Jung's theory of type and is concerned mainly with conscious elements of the personality. It assumes that to function well, an individual must have a well-developed system for perception and a well-developed system for making decisions or…

  12. The Myers-Briggs Type Indicator: A Resource for Developmental Advising.

    Science.gov (United States)

    Gordon, Virginia N.; Carberry, Julie Dryden

    1984-01-01

    The Myers-Briggs Type Indicator (MBTI), a practical tool for helping students understand some of the dynamics of how they communicate and approach the decision making process, is described as an instrument that can be a valuable source of information for students and advisors. (Author/MLW)

  13. Differences in Myers-Briggs Personality Types among High School Band, Orchestra, and Choir Members

    Science.gov (United States)

    MacLellan, Christin Reardon

    2011-01-01

    The purpose of this study was to explore personality type differences among high school band, string orchestra, and choir students according to ensemble membership. Participants (N = 355) were high school students who had participated in their school's band, orchestra, or choir for 1 year or more. The author administered the Myers-Briggs Type…

  14. Eysenck Personality Questionnaire and Jungian Myers-Briggs Type Indicator Correlation of Extraversion-Introversion

    Science.gov (United States)

    Steele, Robert S.; Kelly, Thomas J.

    1976-01-01

    C. G. Jung and H. J. Eysenck developed concepts of extraversion-introversion from radically different theoretical orientations. It is hypothesized that given the methods and content similarity of the Eysenck Personality Questionnaire and the Myers-Briggs Type Indicator. Extraversion-Introversion scales of the inventories will be significantly…

  15. Die Aufzeichnungen des Malte Laurids Brigge: novas perspectivas de interpretação

    Directory of Open Access Journals (Sweden)

    Renata Martins

    2012-12-01

    Full Text Available O objetivo deste texto é analisar a experiência do estranho no romance Die Aufzeichnungen des Malte Laurids Brigge, de Rainer Maria Rilke, através de novas perspectivas de interpretação apoiadas, por exemplo, nas teorias psicanalíticas de Sigmund Freud. Vivendo em uma cidade estrangeira (Paris, com a qual ainda não se identifica, o protagonista do romance, Malte Laurids Brigge, descobre um mundo interior novo através de seu choque com experiências do estranho nesse milieu. A revelação de recordações de sua infância e a projeção de seu ego em leituras de narrativas alheias são seus métodos para buscar e afirmar sua identidade.

  16. Dimensions of the Myers-Briggs Type Indicator (MBTI) and the customers’ purchase Intention

    OpenAIRE

    Maryam khalili yadegari; Mohammad Mahmoudi Maymand; Hamidreza Vazirzanjani

    2013-01-01

    Identifying consumers’ motivation would affect target market choice. While motivation enforces and directs consumer behavior, consumer personality also forms his choice behavior regarding his goal achievement. Mayers-Brigges Type Indicator (MBTI), according to Jung theory and psychological conflicts, indicates 16 personality types. In this research, we review how different personality types influence the individuals’ attitude toward VAIO brand image, VAIO laptop knowledge/ involvement, and pu...

  17. Extended Jury criterion

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In this paper,algebraic criteria are established to determine whether or not a real coefficient polynomial has one or two pairs of conjugate complex roots whose moduli are equal to 1 and the other roots have moduli less than 1 directly from its coefficients.The form and the function of the criteria are similar to those of the Jury criterion which can be used to determine whether or not all the moduli of the roots of a real coefficient polynomial are less than 1.

  18. Julia Briggs, Dennis Butts, M.O. Grenby (eds.), Popular Children’s Literature in Britain

    OpenAIRE

    Talairach-Vielmas, Laurence

    2013-01-01

    What is a “popular” children’s book? How can we gauge the popularity of children’s literature, knowing that children’s reading choices and interests are controlled and framed by adults? Julia Briggs, Dennis Butts and M.O. Grenby’s Popular Children’s Literature in Britain tries to bring to the fore notions of popularity and means of assessing it. This edited collection looks at definitions of the “popular” and examines the relationships between popular literature and children’s literature. As ...

  19. A Galois-Connection between Myers-Briggs' Type Indicators and Szondi's Personality Profiles

    OpenAIRE

    Kramer, Simon

    2014-01-01

    We propose a computable Galois-connection between Myers-Briggs' Type Indicators (MBTIs), the most widely-used personality measure for non-psychiatric populations (based on C.G. Jung's personality types), and Szondi's personality profiles (SPPs), a less well-known but, as we show, finer personality measure for psychiatric as well as non-psychiatric populations (conceived as a unification of the depth psychology of S. Freud, C.G. Jung, and A. Adler). The practical significance of our result is ...

  20. "Presidential Address." Political Pawns in an Educational Endgame: Reflections on Bryant, Briggs, and Some Twentieth-Century School Questions

    Science.gov (United States)

    Graves, Karen

    2013-01-01

    "Newsweek" ran an article on "The Homosexual Teacher" in December 1978. At the end of a tumultuous two-year period framed by Anita Bryant's anti-gay campaign in South Florida and John Briggs' proposition to bar gay and lesbian educators from working in California public schools, reporters concluded, "Most homosexual teachers are deeply plagued by…

  1. The Myers-Briggs Type Indicator as a Tool to Facilitate Learning Outcomes for Team Building in the Classroom

    Science.gov (United States)

    Berry, Priscilla; Wood, Cindy; Thornton, Barry

    2007-01-01

    Globalization and domestic competition are forcing businesses to rethink the human resources utilization process, and one method for considering again this challenge is creating a team culture. One key to this process for human resources development is the understanding of how to create the most successful teams. The use of the Myers-Briggs Type…

  2. Stability Criterion for Humanoid Running

    Institute of Scientific and Technical Information of China (English)

    LIZhao-Hui; HUANGQiang; LIKe-Jie

    2005-01-01

    A humanoid robot has high mobility but possibly risks of tipping over. Until now, one main topic on humanoid robots is to study the walking stability; the issue of the running stability has rarely been investigated. The running is different from the walking, and is more difficult to maintain its dynamic stability. The objective of this paper is to study the stability criterion for humanoid running based on the whole dynamics. First, the cycle and the dynamics of running are analyzed. Then, the stability criterion of humanoid running is presented. Finally, the effectiveness of the proposed stability criterion is illustrated by a dynamic simulation example using a dynamic analysis and design system (DADS).

  3. Bimodal score distributions and the Myers-Briggs Type Indicator: fact or artifact?

    Science.gov (United States)

    Bess, Tammy L; Harvey, Robert J

    2002-02-01

    We examined Myers-Briggs Type Indicator (MBTI) score distributions computed using item response theory (IRT) to assess the generalizability of earlier bimodality reports that have been cited in support of the "type" versus "trait" view of personality. Using the BILOG IRT program to score a sample of approximately 12,000 individuals who participated in leadership development programs, theta score distributions for the 4 dimensions of the MBTI computed using 10 (the BILOG default) versus 50 quadrature points were compared. Results indicated that past reports of bimodality were artifacts caused by BILOG's default use of a small number of quadrature points; when larger numbers of points were used, score distributions became strongly center-weighted. Although our findings are not supportive of the "type"-based hypothesis, the extremely high correlations between theta scores (rs > .996) suggest that no practical differences would be expected as a function of the number-of-quadrature-points decision. PMID:11936208

  4. MUTILAÇÕES DO EU: A FRAGMENTAÇÃO DA IDENTIDADE EM OS CADERNOS DE MALTE LAURIDS BRIGGE, DE RAINER MARIA RILKE

    OpenAIRE

    Alexandre Rodrigues da Costa

    2011-01-01

    This article analyses the fragmentation of the identity in The Notebooks of Malte Laurids Brigge, by Rainer Maria Rilke, to realize how the mutilation can be extended to text and the person who writes it.

  5. MUTILAÇÕES DO EU: A FRAGMENTAÇÃO DA IDENTIDADE EM OS CADERNOS DE MALTE LAURIDS BRIGGE, DE RAINER MARIA RILKE

    Directory of Open Access Journals (Sweden)

    Alexandre Rodrigues da Costa

    2011-01-01

    Full Text Available This article analyses the fragmentation of the identity in The Notebooks of Malte Laurids Brigge, by Rainer Maria Rilke, to realize how the mutilation can be extended to text and the person who writes it.

  6. A Planarity Criterion for Graphs

    CERN Document Server

    Dosen, Kosta

    2012-01-01

    It is proven that a connected graph is planar if and only if all its cocycles with at least four edges are "grounded" in the graph. The notion of grounding of this planarity criterion, which is purely combinatorial, stems from the intuitive idea that with planarity there should be a linear ordering of the edges of a cocycle such that in the two subgraphs remaining after the removal of these edges there can be no crossing of disjoint paths that join the vertices of these edges. The proof given in the paper of the right-to-left direction of the equivalence is based on Kuratowski's Theorem for planarity involving $K_{3,3}$ and $K_5$, but the criterion itself does not mention $K_{3,3}$ and $K_5$. Some other variants of the criterion are also shown necessary and sufficient for planarity.

  7. A Failure Criterion for Concrete

    DEFF Research Database (Denmark)

    Ottosen, N. S.

    1977-01-01

    A four-parameter failure criterion containing all the three stress invariants explicitly is proposed for short-time loading of concrete. It corresponds to a smooth convex failure surface with curved meridians, which open in the negative direction of the hydrostatic axis, and the trace in the devi......A four-parameter failure criterion containing all the three stress invariants explicitly is proposed for short-time loading of concrete. It corresponds to a smooth convex failure surface with curved meridians, which open in the negative direction of the hydrostatic axis, and the trace...

  8. Pragmatism as the philosophical underpinning of the Joanna Briggs meta-aggregative approach to qualitative evidence synthesis

    OpenAIRE

    Hannes, Karin; Lockwood, Craig

    2011-01-01

    Aim This paper presents a discussion of the role of the philosophy of pragmatism in the Joanna Briggs meta-aggregative approach to qualitative evidence synthesis. Background An increasing number of qualitative evidence syntheses are being published in journals, many of them inspired by an interpretive or a critical-realist perspective. One approach to qualitative evidence synthesis is meta-aggregation. Originally designed to model the transparency, auditability and reliability of ...

  9. Conducting systematic reviews of association (etiology): The Joanna Briggs Institute's approach.

    Science.gov (United States)

    Moola, Sandeep; Munn, Zachary; Sears, Kim; Sfetcu, Raluca; Currie, Marian; Lisy, Karolina; Tufanaru, Catalin; Qureshi, Rubab; Mattis, Patrick; Mu, Peifan

    2015-09-01

    The systematic review of evidence is the research method which underpins the traditional approach to evidence-based healthcare. There is currently no uniform methodology for conducting a systematic review of association (etiology). This study outlines and describes the Joanna Briggs Institute's approach and guidance for synthesizing evidence related to association with a predominant focus on etiology and contributes to the emerging field of systematic review methodologies. It should be noted that questions of association typically address etiological or prognostic issues.The systematic review of studies to answer questions of etiology follows the same basic principles of systematic review of other types of data. An a priori protocol must inform the conduct of the systematic review, comprehensive searching must be performed and critical appraisal of retrieved studies must be carried out.The overarching objective of systematic reviews of etiology is to identify and synthesize the best available evidence on the factors of interest that are associated with a particular disease or outcome. The traditional PICO (population, interventions, comparators and outcomes) format for systematic reviews of effects does not align with questions relating to etiology. A systematic review of etiology should include the following aspects: population, exposure of interest (independent variable) and outcome (dependent variable).Studies of etiology are predominantly explanatory or predictive. The objective of reviews of explanatory or predictive studies is to contribute to, and improve our understanding of, the relationship of health-related events or outcomes by examining the association between variables. When interpreting possible associations between variables based on observational study data, caution must be exercised due to the likely presence of confounding variables or moderators that may impact on the results.As with all systematic reviews, there are various approaches to

  10. Determination of epinephrine by the Briggs-Rauscher oscillating system using non-equilibrium stationary state

    Directory of Open Access Journals (Sweden)

    Gao Jinzhang

    2012-01-01

    Full Text Available A highly sensitive method for the determination of epinephrine was proposed, which was based on the perturbation of epinephrine to Briggs-Rauscher oscillating system involving malonic acid, Mn2+, H+, IO3 - and H2O2 at non-equilibrium stationary state. The concentration of KIO3 was chosen as a control parameter to find the bifurcation point in this paper. Results showed that a well linear relationship between the difference of potential and the negative logarithm concentrations of epinephrine existed in the range of 1.1×10-7~5.2×10-9 mol L-1 with a lower detection limit of 6.8×10-10mol L-1 and a correlation coefficient of 0.9974. Compared to the classical oscillating reaction, this method has a lower detection limit and wider linear range. The effects of some foreign species, which may possibly be existed with epinephrine, on determination were also investigated. The proposed method has been successfully used to determine the epinephrine both in the serum and adrenaline hydrochloride injection.

  11. Dimensions of the Myers-Briggs Type Indicator (MBTI and the customers’ purchase Intention

    Directory of Open Access Journals (Sweden)

    Maryam khalili yadegari

    2013-03-01

    Full Text Available Identifying consumers’ motivation would affect target market choice. While motivation enforces and directs consumer behavior, consumer personality also forms his choice behavior regarding his goal achievement. Mayers-Brigges Type Indicator (MBTI, according to Jung theory and psychological conflicts, indicates 16 personality types. In this research, we review how different personality types influence the individuals’ attitude toward VAIO brand image, VAIO laptop knowledge/ involvement, and purchase intention. Also, we find out whether there is any relationship among these variables. Sample of 465 laptop buyers in Tehran markets has been investigated. Buyers’ personality types and their attitude toward variables have been examined by MBTI and 7-point Likert researcher made questionnaires, respectively. The data has been analyzed by SPSS16 software. Research findings indicate that there is a relationship between individuals’ personality type and visual construct of brand image variable (laptop design. Personality types do not indicate significant differences between consumer attitude and product involvement/ knowledge and its purchase intention. Moreover, consumers’ attitude toward brand image, product knowledge/ involvement affects laptop purchase intention. Also, VAIO laptop involvement has significant effect on VAIO brand image.

  12. Dimensions of the Myers-Briggs Type Indicator (MBTI and the customers’ Purchase Intention

    Directory of Open Access Journals (Sweden)

    Mohammad Mahmoudi Maymand

    2013-01-01

    Full Text Available Identifying consumers’ motivation would affect target market choice. While motivationenforces and directs consumer behavior, consumer personality also forms his choice behaviorregarding his goal achievement. Mayers-Brigges Type Indicator (MBTI, according to Jungtheory and psychological conflicts, indicates 16 personality types. In this research, we reviewhow different personality types influence the individuals’ attitude toward VAIO brand image,VAIO laptop knowledge/ involvement, and purchase intention. Also, we find out whetherthere is any relationship among these variables. Sample of 465 laptop buyers in Tehranmarkets has been investigated. Buyers’ personality types and their attitude toward variableshave been examined by MBTI and 7-point Likert researcher made questionnaires,respectively. The data has been analyzed by SPSS16 software. Research findings indicate thatthere is a relationship between individuals’ personality type and visual construct of brandimage variable (laptop design. Personality types do not indicate significant differencesbetween consumer attitude and product involvement/ knowledge and its purchase intention.Moreover, consumers’ attitude toward brand image, product knowledge/ involvement affectslaptop purchase intention. Also, VAIO laptop involvement has significant effect on VAIObrand image.

  13. A Criterion for Regular Sequences

    Indian Academy of Sciences (India)

    D P Patil; U Storch; J Stückrad

    2004-05-01

    Let be a commutative noetherian ring and $f_1,\\ldots,f_r \\in R$. In this article we give (cf. the Theorem in $\\mathcal{x}$2) a criterion for $f_1,\\ldots,f_r$ to be regular sequence for a finitely generated module over which strengthens and generalises a result in [2]. As an immediate consequence we deduce that if $V(g_1,\\ldots,g_r) \\subseteq V(f_1,\\ldots,f_r)$ in Spec and if $f_1,\\ldots,f_r$ is a regular sequence in , then $g_1,\\ldots,g_r$ is also a regular sequence in .

  14. Efficient Verification of Tunnell's Criterion

    OpenAIRE

    Bach, Eric; Ryan, Nathan C.

    2007-01-01

    An integer $n$ is congruent if there is a triangle with rational sides whose area is $n$. In the 1980s Tunnell gave an algorithm to test congruence which relied on counting integral points on the ellipsoids $2x^2+y^2+8z^2 = n$ and $2x^2+y^2+32z^2=n$. The correctness of this algorithm is conditional on the conjecture of Birch and Swinnerton-Dyer. The known methods for testing Tunnell's criterion use $O(n)$ operations. In this paper we give several methods with smaller expo...

  15. LINGVISTIČKA ANALIZA KNJIŽEVNIH TEKSTOVA NA PRIMJERU ROMANA R.M. RILKEA "AUFZEICHNUNGEN DES MALTE LAURIDS BRIGGE"

    OpenAIRE

    Jourdy, Natalja

    2009-01-01

    U prilogu se lingvistički analizira tekst R.M. Rilkea Die Aufzeichnungen des Malte Laurids Brigge. U prvom se redu razmatraju oblici i tehnike pripovijedanja te status i funkcije pripovjedača. Iz teksta se da zaključiti da je spomenuti tekst suvremen ne samo sadržajno nego i jezično, tj. u cijelom se tekstu progresivno destruira tradicionalne paradigme pripovijedanja: one se povlače pred novim oblicima i tehnikama pripovijedanja (slobodni neupravni govor, unutarnji monolog, tok svije...

  16. The Joanna Briggs Institute Best Practice Information Sheet: Nurse-led interventions to reduce cardiac risk factors in adults.

    Science.gov (United States)

    2010-09-01

    This Best Practice Information Sheet updates and supersedes an earlier publication of the Joanna Briggs Institute in 2005. The information that is contained in this publication is based upon a systematic review of six randomized clinical trials. Additional information has been derived from a second systematic review; thus, in total, the information is derived from 22 randomized controlled trials. The original references can be sourced from the systematic reviews. Coronary heart disease (CHD) is the major cause of illness in Western society and it is becoming increasingly important to establish effective strategies in order to reduce the incidence of CHD. Nurse-led clinics are becoming more prominent in community settings and the importance of nurse interventions in the management of CHD and risk factor reduction is recognized in terms of improved health outcomes for patients. However, the variation in outcome measures and inconsistent findings between some studies make it difficult to draw firm conclusions. PMID:20727078

  17. An ethical criterion for geoscientists

    Science.gov (United States)

    Peppoloni, Silvia

    2013-04-01

    Anthropological researches have demonstrated that at some point in human history, man makes an evolutive jump in cultural sense: at first, he is able to perceive himself only as part of a community, later he becomes able to perceive himself as an individual. The analysis of the linguistic roots of the word "Ethics" discloses the traces of this evolutive transition and an original double meaning: on the one hand, "Ethics" contains a sense of belonging to the social fabric, on the other hand, it is related to the individual sphere. These two existential conditions (social and individual) unexpectedly co-exist in the word "Ethics". So, "Geo-Ethics" can be defined as the investigation and reflection on those values upon which to base appropriate behaviours and practices regarding the Geosphere (social dimension), but also as the analysis of the relationships between the geoscientist who acts and his own actions (individual dimension). Therefore, the meaning of the word "Geo-Ethics" calls upon geoscientists to face the responsibility of an ethical behaviour. What does this responsibility consist of and what motivations are necessary to push geoscientists to practice the Earth sciences in an ethical way? An ethical commitment exists if there is research of truth. In their activities, Geoscientists should be searchers and defenders of truth. If geoscientists give up this role, they completely empty of meaning their work. Ethical obligations arise from the possession of specific knowledge that has practical consequences. Geoscientists, as active and responsible part of society, have to serve society and the common good. The ethical criterion for a geoscientist should be rooted in his individual sphere, that is the source of any action even in the social sphere, and should have the intellectual honesty as main requirement. It includes: • respect for the truth that they look for and for other's ideas; • recognition of the value of others as valuable for themselves;

  18. Envy as a Criterion for Distributive Justice

    Directory of Open Access Journals (Sweden)

    Gustavo Pereira

    2001-06-01

    Full Text Available This paper is concerned with the search for a limiting criterion for the inequalities admitted in every distrtbution of resources. Taking as a standpoint Rawls' principie of difference, it will be suggested as limiting criterion of inequality the appearance of feelings of envy, due to the perception of great differences in the possession of resources. This criterion is founded in the problems of stability that envy generates, since people that envy someone's possession of goods will stop being fully cooperative agents, and both individual autonomy as well as social stability will be questioned.

  19. Incubation time fracture criterion for FEM simulations

    Institute of Scientific and Technical Information of China (English)

    Vladimir Bratov

    2011-01-01

    The paper is discussing problems connected with embedment of the incubation time criterion for brittle fracture into finite element computational schemes. Incubation time fracture criterion is reviewed; practical questions of its numerical implementation are extensively discussed. Several examples of how the incubation time fracture criterion can be used as fracture condition in finite element computations are given. The examples include simulations of dynamic crack propagation and arrest,impact crater formation(i.e. fracture in initially intact media),spall fracture in plates,propagation of cracks in pipelines. Applicability of the approach to model initiation,development and arrest of dynamic fracture is claimed.

  20. The qualitative criterion of transient angle stability

    DEFF Research Database (Denmark)

    Lyu, R.; Xue, Y.; Xue, F.;

    2015-01-01

    In almost all the literatures, the qualitative assessment of transient angle stability extracts the angle information of generators based on the swing curve. As the angle (or angle difference) of concern and the threshold value rely strongly on the engineering experience, the validity and robust of...... these criterions are weak. Based on the stability mechanism from the extended equal area criterion (EEAC) theory and combining with abundant simulations of real system, this paper analyzes the criterions in most literatures and finds that the results could be too conservative or too optimistic. It is...

  1. Hilbert-Mumford criterion for nodal curves

    CERN Document Server

    Li, Jun

    2011-01-01

    We prove by Hilbert-Mumford criterion that a slope stable polarized weighted pointed nodal curve is Chow asymptotic stable. This generalizes the result of Caporaso on stability of polarized nodal curves, and of Hasset on weighted pointed stable curves polarized by the weighted dualizing sheaves. It also solved a question raised by Mumford and Gieseker to prove the Chow asymptotic stability of stable nodal curves by Hilbert-Mumford criterion.

  2. The qualitative criterion of transient angle stability

    OpenAIRE

    Lyu, R; Xue, Y.; Xue, F; Wu, Qiuwei; Yang, Guangya; Zhou, H; Ju, P.

    2015-01-01

    In almost all the literatures, the qualitative assessment of transient angle stability extracts the angle information of generators based on the swing curve. As the angle (or angle difference) of concern and the threshold value rely strongly on the engineering experience, the validity and robust of these criterions are weak. Based on the stability mechanism from the extended equal area criterion (EEAC) theory and combining with abundant simulations of real system, this paper analyzes the crit...

  3. Wiener criterion for X-elliptic operators

    Science.gov (United States)

    Tralli, Giulio; Uguzzoni, Francesco

    2015-12-01

    In this note we prove a Wiener criterion of regularity of boundary points for the Dirichlet problem related to X-elliptic operators in divergence form enjoying the doubling condition and the Poincaré inequality. As a step towards this result, we exhibit some other characterizations of regularity in terms of the capacitary potentials. Finally, we also show that a cone-type criterion holds true in our setting.

  4. On the Smoothed Minimum Error Entropy Criterion

    OpenAIRE

    Badong Chen; Principe, Jose C.

    2012-01-01

    Recent studies suggest that the minimum error entropy (MEE) criterion can outperform the traditional mean square error criterion in supervised machine learning, especially in nonlinear and non-Gaussian situations. In practice, however, one has to estimate the error entropy from the samples since in general the analytical evaluation of error entropy is not possible. By the Parzen windowing approach, the estimated error entropy converges asymptotically to the entropy of the error plus an indepe...

  5. The Role of the Myers-Briggs Personality Type and Emotional Intelligence in Marital Satisfaction among Married Female Students at Tehran University.

    Science.gov (United States)

    Shirzad, Galin

    2016-01-01

    The present descriptive correlational study was conducted to predict the role of emotional intelligence and the Myers-Briggs personality type in marital satisfaction in married female students Tehran University in 2015. The study population consisted of all the married female students at Tehran University who visited Iran MBTI center between 22.04.2015 and 21.06.2015. A total of 140 students were selected as the study samples. Data were collected using the Myer-Briggs Type Indicator, the Bar-On Emotional Intelligence Questionnaire and the Enrich Marital Satisfaction Scale and were then analyzed in SPSS-20 using the multivariate regression analysis. The results obtained showed that emotional intelligence (interpersonal and intra-personal skills) and personality type (extraverted and structured) can predict marital satisfaction. PMID:27302443

  6. Reinterpreting the Myers-Briggs Type Indicator from the perspective of the five-factor model of personality.

    Science.gov (United States)

    McCrae, R R; Costa, P T

    1989-03-01

    The Myers-Briggs Type Indicator (MBTI; Myers & McCaulley, 1985) was evaluated from the perspectives of Jung's theory of psychological types and the five-factor model of personality as measured by self-reports and peer ratings on the NEO Personality Inventory (NEO-PI; Costa & McCrae, 1985b). Data were provided by 267 men and 201 women ages 19 to 93. Consistent with earlier research and evaluations, there was no support for the view that the MBTI measures truly dichotomous preferences or qualitatively distinct types; instead, the instrument measures four relatively independent dimensions. The interpretation of the Judging-Perceiving index was also called into question. The data suggest that Jung's theory is either incorrect or inadequately operationalized by the MBTI and cannot provide a sound basis for interpreting it. However, correlational analyses showed that the four MBTI indices did measure aspects of four of the five major dimensions of normal personality. The five-factor model provides an alternative basis for interpreting MBTI findings within a broader, more commonly shared conceptual framework. PMID:2709300

  7. Aesthetical criterion in art and science

    CERN Document Server

    Milovanović, Miloš

    2016-01-01

    In the paper, the authors elaborate some recently published research concerning the originality of artworks in terms of self-organization in the complex systems physics. It has been demonstrated that the originality issue such conceived leads to the criterion of a substantial aesthetics whose applicability is not restricted to the fine arts domain only covering also physics, biology, cosmology and other fields construed in the complex systems terms. Moreover, it is about a truth criterion related to the traditional personality conception revealing the ontological context transcendent to the gnoseological dualism of subjective and objective reality that is characteristic of modern science and humanities. Thus, it is considered to be an aesthetical criterion substantiating art and science as well as the other developments of the postmodern era. Its impact to psychology, education, ecology, culture and other humanities is briefly indicated.

  8. Fracture Criterion for Fracture Mechanics of Magnets

    Institute of Scientific and Technical Information of China (English)

    潘灏; 杨文涛

    2003-01-01

    The applicability and limitation of some fracture criteria in the fracture mechanics of magnets are studied.It is shown that the magnetic field intensity factor can be used as a fracture criterion when the crack in a magnet is only affected by a magnetic field. For some magnetostrictive materials in which the components of magnetostriction strain do not satisfy the compatibility equation of deformation, the stress intensity factor can no longer be effectively applicable as a fracture criterion when the crack in a magnet is affected by a magnetic field and mechanical loads simultaneously.

  9. Stability Criterion for a Finned Spinning Projectile

    Directory of Open Access Journals (Sweden)

    S. D. Naik

    2000-01-01

    Full Text Available The state-of-the-art in gun projectile technology has been used for the aerodynamic stabilisation.This approach is acceptable for guided and controlled rockets but the free-flight rockets suffer fromunacceptable dispersion. Sabot projectiles with both spin and fms developed during the last decadeneed careful analysis. In this study, the second method of Liapunov has been used to develop stability criterion for a projectile to be designed with small fins and is made to spin in the flight. This criterion is useful for the designer.

  10. A new objective criterion for IRIS localization

    International Nuclear Information System (INIS)

    Iris localization is the most important step in iris recognition systems. For commonly used databases, exact data is not given which describe the true results of localization. To cope with this problem a new objective criterion for iris localization is proposed in this paper based on our visual system. A specific number of points are selected on pupil boundary, iris boundary, upper eyelid and lower eyelid using the original image and then distance from these points to the result of complete iris localization has been calculated. If the determined distance is below a certain threshold then iris localization is considered correct. Experimental results show that proposed criterion is very effective. (author)

  11. Selecting Items for Criterion-Referenced Tests.

    Science.gov (United States)

    Mellenbergh, Gideon J.; van der Linden, Wim J.

    1982-01-01

    Three item selection methods for criterion-referenced tests are examined: the classical theory of item difficulty and item-test correlation; the latent trait theory of item characteristic curves; and a decision-theoretic approach for optimal item selection. Item contribution to the standardized expected utility of mastery testing is discussed. (CM)

  12. Luoyang Dual Spatial Criterion Ecological City Construction

    Institute of Scientific and Technical Information of China (English)

    Wang Fazeng; Wang Shengnan

    2007-01-01

    The construction of an ecological city has two foundational platforms:the small platform,namely urban district or simply called as"city ecosystem";and the big platform,namely around city district in certain region scope or also referred to as"city-region ecosystem".The construction of an ecological city must be launched in the dual spatial criteria:in city(urban district)criterion-optimizing the city ecosystem;in city-region(city territory)criterion-optimizing the city-region ecosystem.Luoyang has the bright characteristic and the typical image within cities of China,and even in the world.The construction of anecological city in dual spatial criteria-the city and the city-region-has the vital significance to urbanization advancement and sustainable development in Luoyang.In city-region criterion,the primary mission of Luoyang's ecological city construction is to create a fine ecological environment platform in its city territory.In city criterion,the basic duty of Luoyang's ecologic city construction is to enhance the ecological capacity and benefit of the central city.

  13. Identical Synchronous Criterion for a Coupling System

    Institute of Scientific and Technical Information of China (English)

    HUANGXiangao; ANOWei; LUOXinmin; ZHUFuchen

    2004-01-01

    A new identical synchronous criterion of a coupling system, which is the time average of the derivative of the Lyapunov function, is proposed to determine the synchronous occurrence of any coupling system. Three examples with linear or nonlinear feedback synchronous systems are introduced to test some synchronous parameters that are the conditional Lyapunov exponents, the time average of the derivative of the Lyapunov function,the mean square error of the synchronization. Having obtained the synchronous parameters with the change of the feedback gains, we discover that Pecora and Carroll's criterion and He and Vaidya's reduced criterion are only fit to determine the synchronization of the identical selfsynchronization system which is a special example in the coupling systems, and are not taken as the general identical synchronous criterion of any coupling system. However,no matter whether the largest conditional Lyapunov exponent or the derivative of the Lyapunov function is positive or negative, synchronization of the coupling systems will occur,as long as the average change ratio of the derivative of the Lyapunov function tends to zero.

  14. The Leadership Criterion in Technological Institute

    International Nuclear Information System (INIS)

    This paper introduces the Direction's 'Decision Making Practice'. It has recently been reviewed with the merging of the beddings of the Leadership Criterion (CE-PNQ). These changes improved the control of institutional plans of action which are the result of the global performance critical analysis and other information associated with the Decision Making Practice. (author)

  15. Stability Criterion for Discrete-Time Systems

    Directory of Open Access Journals (Sweden)

    K. Ratchagit

    2010-01-01

    Full Text Available This paper is concerned with the problem of delay-dependent stability analysis for discrete-time systems with interval-like time-varying delays. The problem is solved by applying a novel Lyapunov functional, and an improved delay-dependent stability criterion is obtained in terms of a linear matrix inequality.

  16. The definition and criterion of death.

    Science.gov (United States)

    Bernat, James L

    2013-01-01

    The definition and criterion of death have been rendered ambiguous by developments in organ support technology, particularly the positive-pressure ventilator and vasopressor medications, that uncouple the unitary loss of vital functions in death and create cases in which the brain has been destroyed while circulation and ventilation can be supported. Developing a biophilosophic analysis of the meaning of death before physicians can declare it requires four sequential steps: (1) agreement on the paradigm conditions that frame the analysis and clarify the task; (2) identifying the definition of death, which makes explicit the meaning of death that is accepted in our consensual usage of the term but that has become obscured by technology; (3) identifying the criterion of death that shows that the definition has been fulfilled, and that can be incorporated into a death statute; and (4) devising bedside tests of death for physicians to perform to satisfy the criterion. Although there is a strong consensus on death determination medical standards in countries around the world that has been enshrined into laws, and accepted by most societies and religions, there remains an active dispute among scholars on the precise definition and criterion of death. PMID:24182395

  17. A scale invariance criterion for LES parametrizations

    Directory of Open Access Journals (Sweden)

    Urs Schaefer-Rolffs

    2015-01-01

    Full Text Available Turbulent kinetic energy cascades in fluid dynamical systems are usually characterized by scale invariance. However, representations of subgrid scales in large eddy simulations do not necessarily fulfill this constraint. So far, scale invariance has been considered in the context of isotropic, incompressible, and three-dimensional turbulence. In the present paper, the theory is extended to compressible flows that obey the hydrostatic approximation, as well as to corresponding subgrid-scale parametrizations. A criterion is presented to check if the symmetries of the governing equations are correctly translated into the equations used in numerical models. By applying scaling transformations to the model equations, relations between the scaling factors are obtained by demanding that the mathematical structure of the equations does not change.The criterion is validated by recovering the breakdown of scale invariance in the classical Smagorinsky model and confirming scale invariance for the Dynamic Smagorinsky Model. The criterion also shows that the compressible continuity equation is intrinsically scale-invariant. The criterion also proves that a scale-invariant turbulent kinetic energy equation or a scale-invariant equation of motion for a passive tracer is obtained only with a dynamic mixing length. For large-scale atmospheric flows governed by the hydrostatic balance the energy cascade is due to horizontal advection and the vertical length scale exhibits a scaling behaviour that is different from that derived for horizontal length scales.

  18. A Solvability Criterion for Finite Groups

    Institute of Scientific and Technical Information of China (English)

    Guo Hua QIAN; Tian Ze LI

    2016-01-01

    We show that if for every prime p, the normalizer of a Sylow p-subgroup of a finite group G admits a p-solvable supplement, then G is solvable. This generalizes a solvability criterion of Hall which asserts that a finite group G is solvable if and only if G has a Hall p?-subgroup for every prime p.

  19. Relationship between DHI production values and Myers-Briggs type indicator as a measure of management ability.

    Science.gov (United States)

    Young, A J; Walters, J L

    2002-08-01

    Associations between owners' Myers-Briggs Type Indicator (MBTI) preferences (E = extraversion vs. I = introversion; S = sensing vs. N = intuition; T = thinking vs F = feeling; J = judging vs. P = perceiving) and 21 Dairy Herd Improvement (DHI) production variables were determined on 60 farms. Of 60 dairy farmers participating, 51 were from Holstein farms (85%) and nine from farms with other breeds, primarily Jersey. Cows were milked either twice (n = 44 herds, 73%) or three times (n = 16) per day. Farmers were evenly split between the "E" and "I" dimension, whereas 93% of the farmers were "S," 75% "T," and 62% "J.". Individuals with a preference for the "I" dimension were associated with higher peak and mature equivalent milk yield than those individuals with a preference for the "E" dimension. The "T" and "J" dimensions had a significantly higher percentage of the herd with records usable by USDA and a lower percentage of animals pregnant by the goal set by the dairy producer than the "F" and "P" dimensions. Herds managed by individuals with a combination preference of "E" and "P" produced 7 to 10 kg of 3.5% FCM/cow per day less or 1,820 to 2,752 kg/ cow RHA ECM less than other combinations of the "E-I" and "J-P" dimensions. Those herds also had longer days dry and a lower percentage of records usable by USDA, suggesting that the "E-P" preference is less favorably associated to those measures of herd performance. The MBTI had limited association with many DHI production variables, but relationships to measures of labor and business management should be examined.

  20. A comparison of music education and music therapy majors: personality types as described by the Myers-Briggs Type Indicator and demographic profiles.

    Science.gov (United States)

    Steele, Anita Louise; Young, Sylvester

    2008-01-01

    The purpose of this study was to develop both personality and demographic profiles for students who are interested in majoring in music education or music therapy. Two primary questions were addressed in the study: (a) Are there similarities and differences in the personality types of music education and music therapy majors as measured by the Myers Briggs Type Indicator (MBTI )? (b) Are there similarities and differences in demographic characteristics of music education and music therapy majors in regard to (i) principal instrument studied in college, (ii) grade point average, (iii) scholarship awards, (iv) high school participation in private study and (v) ensembles, (vi) church/community participation, and (vii) volunteerism in high school?

  1. Information criterion based fast PCA adaptive algorithm

    Institute of Scientific and Technical Information of China (English)

    Li Jiawen; Li Congxin

    2007-01-01

    The novel information criterion (NIC) algorithm can find the principal subspace quickly, but it is not an actual principal component analysis (PCA) algorithm and hence it cannot find the orthonormal eigen-space which corresponds to the principal component of input vector.This defect limits its application in practice.By weighting the neural network's output of NIC, a modified novel information criterion (MNIC) algorithm is presented.MNIC extractes the principal components and corresponding eigenvectors in a parallel online learning program, and overcomes the NIC's defect.It is proved to have a single global optimum and nonquadratic convergence rate, which is superior to the conventional PCA online algorithms such as Oja and LMSER.The relationship among Oja, LMSER and MNIC is exhibited.Simulations show that MNIC could converge to the optimum fast.The validity of MNIC is proved.

  2. Optimization of laminates subjected to failure criterion

    Directory of Open Access Journals (Sweden)

    E. Kormaníková

    2011-01-01

    Full Text Available The paper is aimed on laminate optimization subjected to maximum strain criterion. The optimization problem is based on the use of continuous design variables. The thicknesses of layers with the known orientation are used as design variables. The optimization problem with strain constraints are formulated to minimize the laminate weight. The design of the final thickness is rounded off to integer multiples of the commercially available layer thickness.

  3. Certified Subterm Criterion and Certified Usable Rules

    OpenAIRE

    Sternagel, Christian; Thiemann, René

    2010-01-01

    In this paper we present our formalization of two important termination techniques for term rewrite systems: the subterm criterion and the reduction pair processor in combination with usable rules. For both techniques we developed executable check functions in the theorem prover Isabelle/HOL which can certify the correct application of these techniques in some given termination proof. As there are several variants of usable rules we designed our check function in such a way ...

  4. On the hodological criterion for homology

    Directory of Open Access Journals (Sweden)

    Macarena eFaunes

    2015-06-01

    Full Text Available Owen’s pre-evolutionary definition of a homologue as the same organ in different animals under every variety of form and function and its redefinition after Darwin as the same trait in different lineages due to common ancestry entail the same heuristic problem: how to establish sameness. Although different criteria for homology often conflict, there is currently a generalized acceptance of gene expression as the best criterion. This gene-centered view of homology results from a reductionist and preformationist concept of living beings. Here, we adopt an alternative organismic-epigenetic viewpoint, and conceive living beings as systems whose identity is given by the dynamic interactions between their components at their multiple levels of composition. We posit that there cannot be an absolute homology criterion, and instead, homology should be inferred from comparisons at the levels and developmental stages where the delimitation of the compared trait lies. In this line, we argue that neural connectivity, i.e., the hodological criterion, should prevail in the determination of homologies between brain supra-cellular structures, such as the vertebrate pallium.

  5. On the hodological criterion for homology

    Science.gov (United States)

    Faunes, Macarena; Francisco Botelho, João; Ahumada Galleguillos, Patricio; Mpodozis, Jorge

    2015-01-01

    Owen's pre-evolutionary definition of a homolog as “the same organ in different animals under every variety of form and function” and its redefinition after Darwin as “the same trait in different lineages due to common ancestry” entail the same heuristic problem: how to establish “sameness.”Although different criteria for homology often conflict, there is currently a generalized acceptance of gene expression as the best criterion. This gene-centered view of homology results from a reductionist and preformationist concept of living beings. Here, we adopt an alternative organismic-epigenetic viewpoint, and conceive living beings as systems whose identity is given by the dynamic interactions between their components at their multiple levels of composition. We posit that there cannot be an absolute homology criterion, and instead, homology should be inferred from comparisons at the levels and developmental stages where the delimitation of the compared trait lies. In this line, we argue that neural connectivity, i.e., the hodological criterion, should prevail in the determination of homologies between brain supra-cellular structures, such as the vertebrate pallium. PMID:26157357

  6. A generalized three-dimensional Hoek-Brown strength criterion

    Science.gov (United States)

    Zhang, L.

    2008-12-01

    Although the Hoek-Brown strength criterion has been widely used in rock mechanics and rock engineering, it does not take account of the influence of the intermediate principal stress. Much evidence, however, has been accumulating to indicate that the intermediate principal stress does influence the rock strength in many instances. Therefore, researchers have developed three-dimensional (3D) versions of the Hoek-Brown strength criterion. In this paper, three existing 3D versions of the Hoek-Brown strength criterion are reviewed and evaluated. The evaluation shows that all of the three 3D versions of the Hoek-Brown strength criterion have limitations. To address the limitations, a generalized 3D Hoek-Brown criterion is proposed by modifying the generalized Hoek-Brown strength criterion. The proposed 3D criterion not only inherits the advantages of the Hoek-Brown strength criterion but can take account of the influence of the intermediate principal stress. At a 2D stress state (triaxial or biaxial), the proposed 3D criterion will simply reduce to the form of the generalized Hoek-Brown strength criterion. To validate the proposed 3D strength criterion, polyaxial or true triaxial compression test data of intact rocks and jointed rock masses has been collected from the published literature. Predictions of the proposed generalized 3D Hoek-Brown strength criterion are in good agreement with the test data for a range of different rock types. The difference of the proposed generalized 3D Hoek-Brown strength criterion from and its advantages over the existing 3D versions of the Hoek-Brown strength criterion are also discussed. It should be noted that the proposed 3D criterion is empirical in nature because it is an extension of the 2D Hoek-Brown strength criterion, which is empirical. Because of the non-convexity of the yield surface for a biaxial stress state, the proposed 3D criterion may have problems with some stress paths.

  7. Beating the Stoner criterion using molecular interfaces

    Science.gov (United States)

    Ma'Mari, Fatma Al; Moorsom, Timothy; Teobaldi, Gilberto; Deacon, William; Prokscha, Thomas; Luetkens, Hubertus; Lee, Steve; Sterbinsky, George E.; Arena, Dario A.; MacLaren, Donald A.; Flokstra, Machiel; Ali, Mannan; Wheeler, May C.; Burnell, Gavin; Hickey, Bryan J.; Cespedes, Oscar

    2015-08-01

    Only three elements are ferromagnetic at room temperature: the transition metals iron, cobalt and nickel. The Stoner criterion explains why iron is ferromagnetic but manganese, for example, is not, even though both elements have an unfilled 3d shell and are adjacent in the periodic table: according to this criterion, the product of the density of states and the exchange integral must be greater than unity for spontaneous spin ordering to emerge. Here we demonstrate that it is possible to alter the electronic states of non-ferromagnetic materials, such as diamagnetic copper and paramagnetic manganese, to overcome the Stoner criterion and make them ferromagnetic at room temperature. This effect is achieved via interfaces between metallic thin films and C60 molecular layers. The emergent ferromagnetic state exists over several layers of the metal before being quenched at large sample thicknesses by the material's bulk properties. Although the induced magnetization is easily measurable by magnetometry, low-energy muon spin spectroscopy provides insight into its distribution by studying the depolarization process of low-energy muons implanted in the sample. This technique indicates localized spin-ordered states at, and close to, the metal-molecule interface. Density functional theory simulations suggest a mechanism based on magnetic hardening of the metal atoms, owing to electron transfer. This mechanism might allow for the exploitation of molecular coupling to design magnetic metamaterials using abundant, non-toxic components such as organic semiconductors. Charge transfer at molecular interfaces may thus be used to control spin polarization or magnetization, with consequences for the design of devices for electronic, power or computing applications (see, for example, refs 6 and 7).

  8. A criterion autoscheduler for long range planning

    Science.gov (United States)

    Sponsler, Jeffrey L.

    1994-01-01

    A constraint-based scheduling system called SPIKE is used to create long-term schedules for the Hubble Space Telescope. A meta-level scheduler called the Criterion Autoscheduler for Long range planning (CASL) was created to guide SPIKE's schedule generation according to the agenda of the planning scientists. It is proposed that sufficient flexibility exists in a schedule to allow high level planning heuristics to be applied without adversely affected crucial constraints such as spacecraft efficiency. This hypothesis is supported by test data which is described.

  9. An improved criterion for Kapitza's pendulum stability

    International Nuclear Information System (INIS)

    An enhanced and more exact criterion for dynamic stabilization of the parametrically driven inverted pendulum is obtained: the boundaries of stability are determined with greater precision and are valid in a wider region of the system parameters than previous results. The lower boundary of stability is associated with the phenomenon of subharmonic resonances in this system. The relationship of the upper limit of dynamic stabilization of the inverted pendulum with ordinary parametric resonance (i.e. with destabilization of the lower equilibrium position) is established. Computer simulation of the physical system aids the analytical investigation and proves the theoretical results.

  10. Early Stop Criterion from the Bootstrap Ensemble

    DEFF Research Database (Denmark)

    Hansen, Lars Kai; Larsen, Jan; Fog, Torben L.

    1997-01-01

    This paper addresses the problem of generalization error estimation in neural networks. A new early stop criterion based on a Bootstrap estimate of the generalization error is suggested. The estimate does not require the network to be trained to the minimum of the cost function, as required...... by other methods based on asymptotic theory. Moreover, in contrast to methods based on cross-validation which require data left out for testing, and thus biasing the estimate, the Bootstrap technique does not have this disadvantage. The potential of the suggested technique is demonstrated on various time...

  11. A Scoring Criterion For Learning Chain Graphs

    Institute of Scientific and Technical Information of China (English)

    Zhong Guo ZHENG; Jing XU; Xing Wei TONG

    2006-01-01

    A chain graph allows both directed and undirected edges, and contains the underlying mathematical properties of the two. An important method of learning graphical models is to use scoring criteria to measure how well the graph structures fit the data. In this paper, we present a scoring criterion for learning chain graphs based on the Kullback-Leibler distance. It is score equivalent, that is, equivalent chain graphs obtain the same score, so it can be used to perform model selection and model averaging.

  12. Systems interaction and single failure criterion

    International Nuclear Information System (INIS)

    This report documents the results of a six-month study to evaluate the ongoing research programs of the U.S. Nuclear Regulatory Commission (NRC) and U.S. commercial nuclear station owners which address the safety significance of systems interaction and the regulatory adequacy of the single failure criterion. The evaluation of system interactions provided is the initial phase of a more detailed study leading to the development and application of methodology for quantifying the relative safety of operating nuclear plants. (Auth.)

  13. New criterion for algebraic volume density property

    CERN Document Server

    Kaliman, Shulim

    2012-01-01

    A smooth affine algebraic variety $X$ equipped with an algebraic volume form $\\omega$ has the algebraic volume density property (AVDP) if the Lie algebra generated by completely integrable algebraic vector fields of $\\omega$-divergence zero coincides with the space of all algebraic vector fields of $\\omega$-divergence zero. We develop an effective criterion of verifying whether a given $X$ has AVDP. As an application of this method we establish AVDP for any homogeneous space $X=G/R$ that admits a $G$-invariant algebraic volume form where $G$ is a linear algebraic group and $R$ is a closed reductive subgroup of $G$.

  14. A CRITERION FOR TESTING WHETHER A DIFFERENCE IDEAL IS PRIME

    Institute of Scientific and Technical Information of China (English)

    Chunming YUAN; Xiao-Shan GAO

    2009-01-01

    This paper presents a criterion for testing the irreducibility of a polynomial over an algebraic extension field. Using this criterion and the characteristic set method, the authors give a criterion for testing whether certain difference ascending chains are strong irreducible, and as a consequence, whether the saturation ideals of these ascending chains are prime ideals.

  15. Maximum neighborhood margin criterion in face recognition

    Science.gov (United States)

    Han, Pang Ying; Teoh, Andrew Beng Jin

    2009-04-01

    Feature extraction is a data analysis technique devoted to removing redundancy and extracting the most discriminative information. In face recognition, feature extractors are normally plagued with small sample size problems, in which the total number of training images is much smaller than the image dimensionality. Recently, an optimized facial feature extractor, maximum marginal criterion (MMC), was proposed. MMC computes an optimized projection by solving the generalized eigenvalue problem in a standard form that is free from inverse matrix operation, and thus it does not suffer from the small sample size problem. However, MMC is essentially a linear projection technique that relies on facial image pixel intensity to compute within- and between-class scatters. The nonlinear nature of faces restricts the discrimination of MMC. Hence, we propose an improved MMC, namely maximum neighborhood margin criterion (MNMC). Unlike MMC, which preserves global geometric structures that do not perfectly describe the underlying face manifold, MNMC seeks a projection that preserves local geometric structures via neighborhood preservation. This objective function leads to the enhancement of classification capability, and this is testified by experimental results. MNMC shows its performance superiority compared to MMC, especially in pose, illumination, and expression (PIE) and face recognition grand challenge (FRGC) databases.

  16. A criterion for separating process calculi

    CERN Document Server

    Banti, Federico; Tiezzi, Francesco; 10.4204/EPTCS.41.2

    2010-01-01

    We introduce a new criterion, replacement freeness, to discern the relative expressiveness of process calculi. Intuitively, a calculus is strongly replacement free if replacing, within an enclosing context, a process that cannot perform any visible action by an arbitrary process never inhibits the capability of the resulting process to perform a visible action. We prove that there exists no compositional and interaction sensitive encoding of a not strongly replacement free calculus into any strongly replacement free one. We then define a weaker version of replacement freeness, by only considering replacement of closed processes, and prove that, if we additionally require the encoding to preserve name independence, it is not even possible to encode a non replacement free calculus into a weakly replacement free one. As a consequence of our encodability results, we get that many calculi equipped with priority are not replacement free and hence are not encodable into mainstream calculi like CCS and pi-calculus, t...

  17. Extended equal areas criterion: foundations and applications

    Energy Technology Data Exchange (ETDEWEB)

    Yusheng, Xue [Nanjim Automation Research Institute, Nanjim (China)

    1994-12-31

    The extended equal area criterion (EEAC) provides analytical expressions for ultra fast transient stability assessment, flexible sensitivity analysis, and means to preventive and emergency controls. Its outstanding performances have been demonstrated by thousands upon thousands simulations on more than 50 real power systems and by on-line operation records in an EMS environment of Northeast China Power System since September 1992. However, the researchers have mainly based on heuristics and simulations. This paper lays a theoretical foundation of EEAC and brings to light the mechanism of transient stability. It proves true that the dynamic EEAC furnishes a necessary and sufficient condition for stability of multi machine systems with any detailed models, in the sense of the integration accuracy. This establishes a new platform for further advancing EEAC and better understanding of problems. An overview of EEAC applications in China is also given in this paper. (author) 30 refs.

  18. Nash equilibrium and multi criterion aerodynamic optimization

    Science.gov (United States)

    Tang, Zhili; Zhang, Lianhe

    2016-06-01

    Game theory and its particular Nash Equilibrium (NE) are gaining importance in solving Multi Criterion Optimization (MCO) in engineering problems over the past decade. The solution of a MCO problem can be viewed as a NE under the concept of competitive games. This paper surveyed/proposed four efficient algorithms for calculating a NE of a MCO problem. Existence and equivalence of the solution are analyzed and proved in the paper based on fixed point theorem. Specific virtual symmetric Nash game is also presented to set up an optimization strategy for single objective optimization problems. Two numerical examples are presented to verify proposed algorithms. One is mathematical functions' optimization to illustrate detailed numerical procedures of algorithms, the other is aerodynamic drag reduction of civil transport wing fuselage configuration by using virtual game. The successful application validates efficiency of algorithms in solving complex aerodynamic optimization problem.

  19. Application of Geometric Midline Yield Criterion for Strip Drawing

    Institute of Scientific and Technical Information of China (English)

    WANG Gen-ji; DU Hai-jun; ZHAO De-wen; LIU Xiang-hua; WANG Guo-dong

    2009-01-01

    A new linear yield criterion expressed by the geometric midline of error triangle between Tresca and Twin shear stress yield loci on the π-plane in Haigh-Westergaard space was introduced. The criterion was written in terms of the values of principal stress deviator and called GM yield criterion for short. Together with a Cartesian coordinate velocity field instead of the Avitzur's, the GM criterion was used to obtain an analytical solution for strip drawing. With a working example of the strip drawing through wedge-shaped die, the results of relative drawing stress calcu-lated by the GM criterion were compared with those calculated by Mises' criterion from Avitzur formula. It indicated that the calculated results according to analytical solution were in good agreement with the numerical solution ob-tained from Avitzur formula.

  20. Criterion for phase separation in one-dimensional driven systems

    OpenAIRE

    Kafri, Y.; Levine, E.; Mukamel, D.; Schütz, G. M.; Török, J

    2002-01-01

    A general criterion for the existence of phase separation in driven density-conserving one-dimensional systems is proposed. It is suggested that phase separation is related to the size dependence of the steady-state currents of domains in the system. A quantitative criterion for the existence of phase separation is conjectured using a correspondence made between driven diffusive models and zero-range processes. The criterion is verified in all cases where analytical results are available, and...

  1. A study of the energy yield criterion of geomaterials

    Institute of Scientific and Technical Information of China (English)

    Gao Hong; Zheng Yingren; Feng Xiating; Zeng Jing

    2010-01-01

    The study results of the internal friction character of geomaterials conclude that the internal friction exists in mechanical elements all the time having a direction opposite to the shear stress,and the deformation failure mechanism of geomaterials greatly differs from that of metals.For metals,the failure results from shear stresses make the crystal structure slip;whereas for geomaterials,owing to its attribute of granular structures,their deformation follows the friction law,it is the co-action of shear stresses and perpendicular stresses that makes grains overcome the frictions between them,thus leading to the final failure of relative sliding.Therefore,on the basis of the cognition above,a triple shear energy criterion is proposed.Its corresponding Drucker-Prager criterion for geomaterials is also given.The new criterion can be rewritten to the Mohr-Coulomb criterion by neglecting the effect of the intermediate principal stress,and to the Mises criterion by not taking the internal friction angle into consideration.Then the studies of yield criteria commonly used are conducted systematical]y from the points of stress,strain and energy of geomaterials.The results show that no matter which expression form of stress,strain or energy is used for the yield criterion,the essence is the same and the triple shear energy yield criterion is the unified criterion of materials.Finally,the experimental verification is conducted in connection with the practical application of the triple shear energy yield criterion in an engineering project,and the calculation result shows that the Mohr-Coulomb criterion which only takes the single shear surface into account is more conservative than the energy criterion that does consider the effect of triple shear surfaces.

  2. Jeans criterion in a turbulent medium

    Science.gov (United States)

    Bonazzola, S.; Falgarone, E.; Heyvaerts, J.; Perault, M.; Puget, J. L.

    1986-10-01

    According to the classical Jeans analysis, all the molecular clouds of mass larger than a few 100 M(solar), size larger than about 1pc and kinetic temperature Tk less than 30K are gravitationally unstable. We have shown that in clouds supported by internal supersonic motions, local gravitational instabilities may appear within molecular clouds which are globally stable. The argument is threefold: (1) when the turbulent kinetic energy is included into the internal energy term, the virial equilibrium condition shows that molecular clouds such as those observed, which are gravitationally unstable according to the Jeans criterion, are indeed globally stable if supported by a turbulent velocity field of power spectrum steeper than 3; (2) 2D compressible hydrodynamical simulations show that a supersonic turbulent velocity field generates a turbulent pressure within clouds, the gradients of which stabilize the unstable scales (i.e., the largest scales and the cloud itself) against gravitational collapse; (3) an analysis similar to the Jeans approach but including the turbulent pressure gradient term, gives basically the same results as those given in (1). Clouds of mean density lower than a critical value are found to be stable even though more massive than their Jeans mass. In clouds of mean density larger than that critical value, the gravitational instability appears only over a range of scales smaller than the cloud size, the largest scales being stable. In practice, the observed mean densities are lower than this critical value: the observation of a small number of cores and stars of a few solar masses embedded in clouds of several hundred solar masses can only be understood in terms of small scale density fluctuations of large amplitude generated by the supersonic turbulence which would occasionally overtake the limit of gravitational stability.

  3. Criterion-Referenced Measurement: Half a Century Wasted?

    Science.gov (United States)

    Popham, W. James

    2014-01-01

    Fifty years ago, Robert Glaser introduced the concept of criterion-referenced measurement in an article in American Psychologist. Its early proponents predicted that this measurement strategy would revolutionize education. But has it lived up to its promise? W. James Popham explores this question by looking at the history of criterion-referenced…

  4. SAFETY MARGIN CRITERION OF NONLINEAR UNBALANCE ELASTIC AXLE SYSTEM

    Institute of Scientific and Technical Information of China (English)

    陈予恕; 李银山; 薛禹胜

    2003-01-01

    The safety margin criterion of nonlinear dynamic question of an elastic rotor system are given. A series of observing spaces were separated from integral space by resolving and polymerizing method. The stable-state trajectory of high dimensional nonlinear dynamic systems was got within integral space. According to international standard of rotor system vibration, energy limits of safety criterion were determined. The safety margin was calculated within a series of observing spaces by comparative positive-area criterion (CPAC) method. A quantitative example calculating safety margin for unbalance elastic rotor system was given by CPAC. The safety margin criterion proposed includes the calculation of current stability margin in engineering. This criterion is an effective method to solve quantitative calculation question of safety margin and stability margin for nonlinear dynamic systems.

  5. Kinematical analysis of highway tunnel collapse using nonlinear failure criterion

    Institute of Scientific and Technical Information of China (English)

    杨小礼; 杨子汉; 潘秋景; 李育林

    2014-01-01

    For different kinds of rocks, the collapse range of tunnel was studied in the previously published literature. However, some tunnels were buried in soils, and test data showed that the strength envelopes of the soils followed power-law failure criterion. In this work, deep buried highway tunnel with large section was taken as objective, and the basic expressions of collapse shape and region were deduced for the highway tunnels in soils, based on kinematical approach and power-law failure criterion. In order to see the effectiveness of the proposed expressions, the solutions presented in this work agree well with previous results if the nonlinear failure criterion is reduced to a linear Mohr-Coulomb failure criterion. The present results are compared with practical projects and tunnel design code. The numerical results show that the height and width of tunnel collapse are greatly affected by the nonlinear criterion for the tunnel in soil.

  6. Modified Schur-Cohn Criterion for Stability of Delayed Systems

    Directory of Open Access Journals (Sweden)

    Juan Ignacio Mulero-Martínez

    2015-01-01

    Full Text Available A modified Schur-Cohn criterion for time-delay linear time-invariant systems is derived. The classical Schur-Cohn criterion has two main drawbacks; namely, (i the dimension of the Schur-Cohn matrix generates some round-off errors eventually resulting in a polynomial of s with erroneous coefficients and (ii imaginary roots are very hard to detect when numerical errors creep in. In contrast to the classical Schur-Cohn criterion an alternative approach is proposed in this paper which is based on the application of triangular matrices over a polynomial ring in a similar way as in the Jury test of stability for discrete systems. The advantages of the proposed approach are that it halves the dimension of the polynomial and it only requires seeking real roots, making this modified criterion comparable to the Rekasius substitution criterion.

  7. Os tipos psicológicos na psicologia analítica de Carl Gustav Jung e o inventário de personalidade “Myers-Briggs Type Indicator (MBTI”: contribuições para a psicologia educacional, organizacional e clínica/The psychological types in analytical psychology of Carl Gustav Jung and the inventory of personality “Myers-Briggs Type Indicator (MBTI”: contributions for the educational, organizational and clinical psychology

    Directory of Open Access Journals (Sweden)

    Luís Marcelo Alves Ramos

    2005-01-01

    Full Text Available O texto apresenta os princípios da Teoria dos Tipos Psicológicos, a mais conhecida face da Psicologia Analítica do psicólogo e psiquiatra suíço Carl Gustav Jung (1875-1961, bem como os fundamentos do Inventário de Personalidade “Myers-Briggs Type Indicator (MBTI”, constituído a partir da tipologia junguiana, e que vem sendo cada vez mais utilizado nos campos da Psicologia Educacional, Organizacional e Clínica. The text presents the principles of the Theory of Psychological Types, the most known face of the Analytical Psychology of the Swiss psychologist and psychiatrist Carl Gustav Jung (1875-1961, as well as the fundamentals of the Inventory of Personality “Myers-Briggs Type Indicator (MBTI”, constituted from the Jungian typology, and which has been more used nowadays by Educational, Organizational and Clinical Psychology.

  8. Industry Software Trustworthiness Criterion Research Based on Business Trustworthiness

    Science.gov (United States)

    Zhang, Jin; Liu, Jun-fei; Jiao, Hai-xing; Shen, Yi; Liu, Shu-yuan

    To industry software Trustworthiness problem, an idea aiming to business to construct industry software trustworthiness criterion is proposed. Based on the triangle model of "trustworthy grade definition-trustworthy evidence model-trustworthy evaluating", the idea of business trustworthiness is incarnated from different aspects of trustworthy triangle model for special industry software, power producing management system (PPMS). Business trustworthiness is the center in the constructed industry trustworthy software criterion. Fusing the international standard and industry rules, the constructed trustworthy criterion strengthens the maneuverability and reliability. Quantitive evaluating method makes the evaluating results be intuitionistic and comparable.

  9. Robust Hammerstein Adaptive Filtering under Maximum Correntropy Criterion

    Directory of Open Access Journals (Sweden)

    Zongze Wu

    2015-10-01

    Full Text Available The maximum correntropy criterion (MCC has recently been successfully applied to adaptive filtering. Adaptive algorithms under MCC show strong robustness against large outliers. In this work, we apply the MCC criterion to develop a robust Hammerstein adaptive filter. Compared with the traditional Hammerstein adaptive filters, which are usually derived based on the well-known mean square error (MSE criterion, the proposed algorithm can achieve better convergence performance especially in the presence of impulsive non-Gaussian (e.g., α-stable noises. Additionally, some theoretical results concerning the convergence behavior are also obtained. Simulation examples are presented to confirm the superior performance of the new algorithm.

  10. Energy Criterion for the Spectral Stability of Discrete Breathers

    Science.gov (United States)

    Kevrekidis, Panayotis G.; Cuevas-Maraver, Jesús; Pelinovsky, Dmitry E.

    2016-08-01

    Discrete breathers are ubiquitous structures in nonlinear anharmonic models ranging from the prototypical example of the Fermi-Pasta-Ulam model to Klein-Gordon nonlinear lattices, among many others. We propose a general criterion for the emergence of instabilities of discrete breathers analogous to the well-established Vakhitov-Kolokolov criterion for solitary waves. The criterion involves the change of monotonicity of the discrete breather's energy as a function of the breather frequency. Our analysis suggests and numerical results corroborate that breathers with increasing (decreasing) energy-frequency dependence are generically unstable in soft (hard) nonlinear potentials.

  11. The Bohm criterion for a dusty plasma sheath

    Indian Academy of Sciences (India)

    B P Pandey; Anjan Dutta

    2005-07-01

    The formation of the sheath in a dusty plasma is investigated. The Bohm criterion is derived for two different cases: (a) when electrons are in thermodynamic equilibrium and dust grains provide the immobile, stationary background and (b) when both electrons and ions are in thermodynamic equilibrium and dust grains are moving. In the first case, Bohm criterion gets modified due to the fluctuation of the charge on the grain surface. In the second case, the collisional and Coulombic drag play important role in determining the Bohm criterion.

  12. Student Preferences and Performance in Online and Face-to-Face Classes Using Myers-Briggs Indicator: A Longitudinal Quasi-Experimental Study

    Directory of Open Access Journals (Sweden)

    Seta Boghikian-Whitby

    2016-05-01

    Full Text Available This longitudinal, quasi-experimental study investigated students’ cognitive personality type using the Myers-Briggs personality Type Indicator (MBTI in Internet-based Online and Face-to-Face (F2F modalities. A total of 1154 students enrolled in 28 Online and 32 F2F sections taught concurrently over a period of fourteen years. The study measured whether the sample is similar to the national average percentage frequency of all 16 different personality types; whether specific personality type students preferred a specific modality of instructions and if this preference changed over time; whether learning occurred in both class modalities; and whether specific personality type students learned more from a specific modality. Data was analyzed using regression, t-test, frequency, and Chi-Squared. The study concluded that data used in the study was similar to the national statistics; that no major differences in preference occurred over time; and that learning did occur in all modalities, with more statistically significant learning found in the Online modality versus F2F for Sensing, Thinking, and Perceiving types. Finally, Sensing and Thinking (ST and Sensing and Perceiving (SP group types learned significantly more in Online modality versus F2F.

  13. Norm Referenced and Criterion Based Measures with Preschoolers

    Science.gov (United States)

    MacTurk, Robert H.; Neisworth, John T.

    1978-01-01

    Seventeen handicapped and nonhandicapped preschool children were given both the norm referenced Gesell Developmental Schedules and the criterion based HICOMP progress measure on a quarterly (10 week) basis. (Author/SBH)

  14. Angular criterion for distinguishing between Fraunhofer and Fresnel diffraction

    CERN Document Server

    Medina, F F; García-Sucerquia, J; Matteucci, G

    2003-01-01

    The distinction between Fresnel and Fraunhofer diffraction is a crucial condition for the accurate analysis of diffracting structures. In this paper we propose a criterion based on the angle subtended by the first zero of the diffraction pattern from the center of the diffracting aperture. The determination of the zero of the diffraction pattern is the crucial point for assuring the precision of the criterion. It mainly depends on the dynamical range of the detector. Therefore, the applicability of adequate thresholds for different detector types is discussed. The criterion is also generalized by expressing it in terms of the number of Fresnel zones delimited by the aperture. Simulations are reported for illustrating the feasibility of the criterion.

  15. Closed Superstrings in a Constant Magnetic Field and Regularization Criterion

    OpenAIRE

    Kokado, Akira; Konisi, Gaku; Saito, Takesi

    2010-01-01

    We propose a new type of interaction of closed superstrings with the electromagnetic field, other than the usual Kaluza-Klein type or a gauge field with internal gauge group origin. This model with a constant magnetic field is also shown to have an exact solution. We consider a regularization criterion. Some models will be excluded according to this criterion. The spectrum-generating algebra is also constructed in our interacting model.

  16. Self-Adjointness Criterion for Operators in Fock Spaces

    Energy Technology Data Exchange (ETDEWEB)

    Falconi, Marco, E-mail: marco.falconi@univ-rennes1.fr [Université de Rennes I, IRMAR and Centre Henri Lebesgue (France)

    2015-12-15

    In this paper we provide a criterion of essential self-adjointness for operators in the tensor product of a separable Hilbert space and a Fock space. The class of operators we consider may contain a self-adjoint part, a part that preserves the number of Fock space particles and a non-diagonal part that is at most quadratic with respect to the creation and annihilation operators. The hypotheses of the criterion are satisfied in several interesting applications.

  17. Stochastic Learning and the Intuitive Criterion in Simple Signaling Games

    DEFF Research Database (Denmark)

    Sloth, Birgitte; Whitta-Jacobsen, Hans Jørgen

    A stochastic learning process for signaling games with two types, two signals, and two responses gives rise to equilibrium selection which is in remarkable accordance with the selection obtained by the intuitive criterion......A stochastic learning process for signaling games with two types, two signals, and two responses gives rise to equilibrium selection which is in remarkable accordance with the selection obtained by the intuitive criterion...

  18. Differential criterion of a bubble collapse in viscous liquids

    CERN Document Server

    Bogoyavlenskiy, V A

    1999-01-01

    The present work is devoted to a model of bubble collapse in a Newtonian viscous liquid caused by an initial bubble wall motion. The obtained bubble dynamics described by an analytic solution significantly depends on the liquid and bubble parameters. The theory gives two types of bubble behavior: collapse and viscous damping. This results in a general collapse condition proposed as the sufficient differential criterion. The suggested criterion is discussed and successfully applied to the analysis of the void and gas bubble collapses.

  19. Trace Ratio Criterion for Feature Extraction in Classification

    Directory of Open Access Journals (Sweden)

    Guoqi Li

    2014-01-01

    Full Text Available A generalized linear discriminant analysis based on trace ratio criterion algorithm (GLDA-TRA is derived to extract features for classification. With the proposed GLDA-TRA, a set of orthogonal features can be extracted in succession. Each newly extracted feature is the optimal feature that maximizes the trace ratio criterion function in the subspace orthogonal to the space spanned by the previous extracted features.

  20. A Code Level Based Programmer Assessment and Selection Criterion Using Metric Tools

    OpenAIRE

    Ezekiel U. Okike

    2014-01-01

    this study presents a code level measurement of computer programs developed by computer programmers using a Chidamber and Kemerer Java metric (CKJM) tool and the Myers Briggs Type Indicator (MBTI) tool. The identification of potential computer programmers using personality trait factors does not seem to be the best approach without a code level measurement of the quality of programs. Hence the need to evolve a metric tool which measures both personality traits of programmers and code level qu...

  1. Formulation of cross-anisotropic failure criterion for soils

    Directory of Open Access Journals (Sweden)

    Yi-fei SUN

    2013-10-01

    Full Text Available Inherently anisotropic soil fabric has a considerable influence on soil strength. To model this kind of inherent anisotropy, a three-dimensional anisotropic failure criterion was proposed, employing a scalar-valued anisotropic variable and a modified general three- dimensional isotropic failure criterion. The scalar-valued anisotropic variable in all sectors of the deviatoric plane was defined by correlating a normalized stress tensor with a normalized fabric tensor. Detailed comparison between the available experimental data and the corresponding model predictions in the deviatoric plane was conducted. The proposed failure criterion was shown to well predict the failure behavior in all sectors, especially in sector II with the Lode angle ranging between 60º and 120º, where the prediction was almost in accordance with test data. However, it was also observed that the proposed criterion overestimated the strength of dense Santa Monica Beach sand in sector III where the intermediate principal stress ratio b varied from approximately 0.2 to 0.8, and slightly underestimated the strength when b was between approximately 0.8 and 1. The difference between the model predictions and experimental data was due to the occurrence of shear bending, which might reduce the measured strength. Therefore, the proposed anisotropic failure criterion has a strong ability to characterize the failure behavior of various soils and potentially allows a better description of the influence of the loading direction with respect to the soil fabric.

  2. SOCIO-PSYCHOLOGICAL CRITERIONS OF FAMILY LIFESTYLE TYPOLOGY

    Directory of Open Access Journals (Sweden)

    Yekaterina Anatolievna Yumkina

    2015-02-01

    Full Text Available The purpose of this article is to present socio-psychological criterions of family lifestyle typology, which were found during theoretical modelling and empirical research work. It is important in fundamental and practical aspects. St-Petersburg students (n = 116, from 19 to 21 years old were examined by special questionnaire «Family relationship and home» (Kunitsi-na V.N., Yumkina Ye.A., 2012 which measures different aspects of family lifestyle. We also used complex of methods that gave us information about personal values, self-rating and parent-child relationships. Dates were divided into six groups according to three main criterions of family lifestyle typology: social environment of family life, family activity, and family interpersonal relationships. There were found statistically significant differences between pairs of group from every criterions. The results can be useful in spheres dealing with family crisis, family development, family traditions etc.

  3. Stability criterion and its calculation for sail-assisted ship

    Directory of Open Access Journals (Sweden)

    Hu Yihuai

    2015-01-01

    Full Text Available Stability criterion and its calculation are the crucial issue in the application of sail-assisted ship. How- ever, there is at present no specific criterion and computational methods for the stability of sail-assisted ship. Based on the stability; requirements for seagoing ships, the stability criterion of the sail-assisted ships is suggested in this paper. Furthermore, how to calculate the parameters and determine some specific coefficients for the ship stability; calculation, as well as how to redraw stability! curve are also discussed in this paper. Finally, to give an illustration, the proposed method is applied on a sail assisted-ship model with comments and recommendations for improvement.

  4. A Joint Optimization Criterion for Blind DS-CDMA Detection

    Directory of Open Access Journals (Sweden)

    Sergio A. Cruces-Alvarez

    2007-01-01

    Full Text Available This paper addresses the problem of the blind detection of a desired user in an asynchronous DS-CDMA communications system with multipath propagation channels. Starting from the inverse filter criterion introduced by Tugnait and Li in 2001, we propose to tackle the problem in the context of the blind signal extraction methods for ICA. In order to improve the performance of the detector, we present a criterion based on the joint optimization of several higher-order statistics of the outputs. An algorithm that optimizes the proposed criterion is described, and its improved performance and robustness with respect to the near-far problem are corroborated through simulations. Additionally, a simulation using measurements on a real software-radio platform at 5 GHz has also been performed.

  5. Kinetic Theory of the Presheath and the Bohm Criterion

    CERN Document Server

    Baalrud, S D

    2013-01-01

    A kinetic theory of the Bohm criterion is developed that is based on positive-exponent velocity moments of the plasma kinetic equation. This result is contrasted with the conventional kinetic Bohm criterion that is based on a v^{-1} moment of the Vlasov equation. The salient difference between the two results is that low velocity particles dominate in the conventional theory, but are essentially unimportant in the new theory. It is shown that the derivation of the conventional kinetic Bohm criterion is flawed. Low velocity particles can cause unphysical divergences in the conventional theory. These divergent contributions are avoided with this new approach. The two theories are compared using example distribution functions from previous presheath models. The importance of ion-ion and electron-electron collisions to determining the particle distribution functions throughout the presheath is also discussed. A kinetic equation that accounts for wave-particle scattering by convective instabilities is used to show...

  6. Many-particle entanglement criterion for superradiant-like states

    CERN Document Server

    Tasgin, Mehmet Emre

    2016-01-01

    We derive a many-particle inseparability criterion for mixed states using the relation between single-mode and many-particle nonclassicalities. It works very well not only in the vicinity of the Dicke states, but also for the superposition of them: superradiant ground state of finite/infinite number of particles and time evolution of single-photon superradiance. We also obtain a criterion for ensemble-field entanglement which works fine for such kind of states. Even though the collective excitations of the many-particle system is sub-Poissonian --which results in entanglement-- the wave function displays bunching.

  7. Acceptance criterion for hydrogen management in nuclear reactor containment

    International Nuclear Information System (INIS)

    In the present work, an open-source CFD based methodology has been presented to predict the pressure rise caused due to deflagration for dry hydrogen air mixtures. A systematic parametric study has been carried out to evaluate the impact of initial conditions such as hydrogen mol fraction and initial temperature in the containment. Based on the results obtained, a new acceptance criterion for the limiting hydrogen mol fraction has been proposed. Such a criterion can be used in conjunction with various hydrogen management schemes to limit the hydrogen concentration to within the specified limit during accident scenarios. (author)

  8. OIL MONITORING DIAGNOSTIC CRITERIONS BASED ON MAXIMUM ENTROPY PRINCIPLE

    Institute of Scientific and Technical Information of China (English)

    Huo Hua; Li Zhuguo; Xia Yanchun

    2005-01-01

    A method of applying maximum entropy probability density estimation approach to constituting diagnostic criterions of oil monitoring data is presented. The method promotes the precision of diagnostic criterions for evaluating the wear state of mechanical facilities, and judging abnormal data. According to the critical boundary points defined, a new measure on monitoring wear state and identifying probable wear faults can be got. The method can be applied to spectrometric analysis and direct reading ferrographic analysis. On the basis of the analysis and discussion of two examples of 8NVD48A-2U diesel engines, the practicality is proved to be an effective method in oil monitoring.

  9. A New Criterion for Disruption Prediction on HL-2A

    Institute of Scientific and Technical Information of China (English)

    YANG Qing-Wei; JI Xiao-Quan; DING Xuan-Tong; HL-2A team; ZHOU Hang-Yu; FENG Bei-Bin; LIU Yi; PAN Yu-Dong; LI Wei; DUAN Xu-Ru; CHEN Wei; CUI Zheng-Ying

    2006-01-01

    @@ A new criterion has been proposed to predict the major disruptions caused by tearing mode instabilities. According to the HL-2A experimental results, the statistical analyses are employed to investigate the relationships between MHD activities and the plasma disruptions. Two kinds of the tearing mode activities can finally cause the disruption on HL-2A operations. By introducing a new parameter, i.e. an integral of poloidal magnetic field over time, as the criterion of disruption precursor, almost all of the disruptions can be predicted.

  10. Non-Equilibrium Gibbs' Criterion for Completely Wetting Volatile Liquids

    CERN Document Server

    Tsoumpas, Yannis; Galvagno, Mariano; Rednikov, Alexey; Ottevaere, Heidi; Thiele, Uwe; Colinet, Pierre

    2014-01-01

    During the spreading of a liquid over a solid substrate, the contact line can stay pinned at sharp edges until the contact angle exceeds a critical value. At (or sufficiently near) equilibrium, this is known as Gibbs' criterion. Here, we show both experimentally and theoretically that for completely wetting volatile liquids there also exists a dynamically-produced critical angle for depinning, which increases with the evaporation rate. This suggests that one may introduce a simple modification of the Gibbs' criterion for (de)pinning, that accounts for the non-equilibrium effect of evaporation.

  11. A convenient accuracy criterion for time domain FE-calculations

    DEFF Research Database (Denmark)

    Jensen, Morten Skaarup

    1997-01-01

    An accuracy criterion that is well suited to tome domain finite element (FE) calculations is presented. It is then used to develop a method for selecting time steps and element meshes that produce accurate results without significantly overburderning the computer. Use of this method is illustrated...

  12. Criterion-Referenced Test Items for Vocational Education. Final Report.

    Science.gov (United States)

    Missouri Univ., Columbia. Instructional Materials Lab.

    A project was conducted to develop and validate criterion-referenced test items for the following vocational education programs: child care worker, machine shop, electronics, drafting, and automobile mechanics. For each of the programs, the following activities took place: a project coordinator was assigned, subject-area instructors and a test…

  13. Utilization of Durability Criterion to Develop Automotive Components

    DEFF Research Database (Denmark)

    Ricardo, Luiz Carlos Hernandes

    2010-01-01

    Today the automotive companies must reduce the time to development of new products with improvement in performance, durability and low cost reductions where possible. To achieve this goal the carmakers need to improve the design criterion of car systems like body, chassis and suspension components...

  14. Satisfying the Einstein-Podolsky-Rosen criterion with massive particles

    DEFF Research Database (Denmark)

    Peise, Jan; Kruse, I.; Lange, K.;

    2016-01-01

    In 1935, Einstein, Podolsky and Rosen (EPR) questioned the completeness of quantum mechanics by devising a quantum state of two massive particles with maximally correlated space and momentum coordinates. The EPR criterion qualifies such continuous-variable entangled states, as shown successfully...

  15. Discriminant Validity as a Scale Evaluation Criterion: Theory or Statistics?

    OpenAIRE

    José Antonio Martínez-García; Laura Martínez-Caro

    2009-01-01

    Discriminant validity is one of the usual criterions for evaluating measurement scales that define latent constructs in social sciences. This article shows how different statistical procedures frequently used for accomplishing this aim can yield misleading results. Authors recommend a theoretical judgement about divergence among scales that are manifestation of latent concepts. Therefore, content validity represents a robust condition against certain covariance statistical based analysis.

  16. Criterion-based laparoscopic training reduces total training time

    NARCIS (Netherlands)

    Brinkman, W.M.; Buzink, S.N.; Alevizos, L.; De Hingh, I.H.J.T.; Jakimowicz, J.J.

    2011-01-01

    The benefits of criterion-based laparoscopic training over time-oriented training are unclear. The purpose of this study is to compare these types of training based on training outcome and time efficiency. Methods During four training sessions within 1 week (one session per day) 34 medical interns (

  17. Criterion-based laparoscopic training reduces total training time

    NARCIS (Netherlands)

    Brinkman, W.M.; Buzink, S.N.; Alevizos, L.; De Hingh, I.H.J.T.; Jakimowicz, J.J.

    2012-01-01

    The benefits of criterion-based laparoscopic training over time-oriented training are unclear. The purpose of this study is to compare these types of training based on training outcome and time efficiency. Methods During four training sessions within 1 week (one session per day) 34 medical interns (

  18. An Elementary Proof of a Criterion for Linear Disjointness

    Science.gov (United States)

    Dobbs, David E.

    2013-01-01

    An elementary proof using matrix theory is given for the following criterion: if "F"/"K" and "L"/"K" are field extensions, with "F" and "L" both contained in a common extension field, then "F" and "L" are linearly disjoint over "K" if (and only if) some…

  19. Verbalizing Facial Memory: Criterion Effects in Verbal Overshadowing

    Science.gov (United States)

    Clare, Joseph; Lewandowsky, Stephan

    2004-01-01

    This article investigated the role of the recognition criterion in the verbal overshadowing effect (VOE). In 3 experiments, people witnessed an event, verbally described a perpetrator, and then attempted identification. The authors found in Experiment 1, which included a "not present" response option and both perpetrator-present (PP) and…

  20. Critical machine cluster identification using the equal area criterion

    DEFF Research Database (Denmark)

    Weckesser, Johannes Tilman Gabriel; Jóhannsson, Hjörtur; Østergaard, Jacob

    2015-01-01

    The paper introduces a new method to early identify the critical machine cluster (CMC) after a transient disturbance. For transient stability assessment with methods based on the equal area criterion it is necessary to split the generators into a group of critical and non-critical machines. The...

  1. Criterion of Semi-Markov Dependent Risk Model

    Institute of Scientific and Technical Information of China (English)

    Xiao Yun MO; Xiang Qun YANG

    2014-01-01

    A rigorous definition of semi-Markov dependent risk model is given. This model is a generalization of the Markov dependent risk model. A criterion and necessary conditions of semi-Markov dependent risk model are obtained. The results clarify relations between elements among semi-Markov dependent risk model more clear and are applicable for Markov dependent risk model.

  2. Creativity.4in1: Four-Criterion Construct of Creativity

    Science.gov (United States)

    Kharkhurin, Anatoliy V.

    2014-01-01

    The purpose of this theoretical article is to provide an extended definition of creativity that embraces potential cross-cultural variations in this construct. Creativity is defined as a 4-criterion construct, which includes attributes of novelty, utility, aesthetics, and authenticity. Novelty attribute stipulates that a creative work brings…

  3. A Gurson-type criterion for porous ductile solids containing arbitrary ellipsoidal voids—II: Determination of yield criterion parameters

    Science.gov (United States)

    Madou, Komlanvi; Leblond, Jean-Baptiste

    2012-05-01

    The aim of this paper is to fully determine the parameters of the approximate homogenized yield criterion for porous ductile solids containing arbitrary ellipsoidal cavities proposed in Part I. This is done through improvements of the limit-analysis of some representative hollow cell presented there. The improvements are of two kinds. For hydrostatic loadings, the limit-analysis is refined by performing micromechanical finite element computations in a number of significant cases, so as to replace Leblond and Gologanu (2008)'s trial velocity field representing the expansion of the void by the exact, numerically determined one. For deviatoric loadings, limit-analysis is dropped and direct use is made of some general rigorous results for nonlinear composites derived by Ponte-Castaneda (1991), Willis (1991) and Michel and Suquet (1992) using the earlier work of Willis (1977) and the concept of "linear comparison material". This hybrid approach is thought to lead to the best possible expressions of the yield criterion parameters. The criterion proposed reduces to (variants of) classical approximate criteria proposed by Gurson (1977) and Gologanu et al. (1993, 1994, 1997) in the specific cases of spherical or spheroidal, prolate or oblate cavities. An overview of the validation of this criterion through micromechanical finite element computations is finally presented.

  4. Logical and Decisive Combining Criterion for Binary Group Decision Making

    Directory of Open Access Journals (Sweden)

    Ivan Vrana

    2010-04-01

    Full Text Available A new combining criterion, the Multiplicative Proportional Deviative Influence (MPDI is presented for combining or aggregating multi-expert numerical judgments in Yes-or-No type ill-structured group decision making situations. This newly proposed criterion performs well in comparison with the widely used aggregation means: the Arithmetic Mean (AM, and Geometric Mean (GM, especially in better reflecting the degree of agreement between criteria levels or numerical experts’ judgments. The MPDI can be considered as another class of combining criteria that make effect of the degree of agreement among multiple numerical judgments. The MPDI is applicable in integrating several collaborative or synergistic decision making systems through combining final numerical decision outputs. A discussion and generalization of the proposed MPDI is discussed withnumerical example.

  5. A Non-Termination Criterion for Binary Constraint Logic Programs

    CERN Document Server

    Payet, Etienne

    2008-01-01

    On the one hand, termination analysis of logic programs is now a fairly established research topic within the logic programming community. On the other hand, non-termination analysis seems to remain a much less attractive subject. If we divide this line of research into two kinds of approaches: dynamic versus static analysis, this paper belongs to the latter. It proposes a criterion for detecting non-terminating atomic queries with respect to binary CLP rules, which strictly generalizes our previous works on this subject. We give a generic operational definition and an implemented logical form of this criterion. Then we show that the logical form is correct and complete with respect to the operational definition.

  6. Experimental research on ductile fracture criterion in metal forming

    Science.gov (United States)

    Yu, Song; Feng, Weiming

    2011-09-01

    Ductile fracture criterion is key limitation parameter in material forming. Accuracy predicting surface and internal failure in plastic deformation process affects on the technology design of workpiece and die greatly. Tension, compression, torsion and shearing test on 45# steel are utilized for providing the experimental values of the critical values at fracture, and 11 widely used ductile fracture criterion are selected to simulate the physical experiments and their relative accuracy for predicting and quantifying fracture initiation sites are investigated. The comparing results show that metal forming process under high triaxiality can be estimated successively using both Normalized Cockcroft-latham and the Brozzo ductile fracture criteria, but the Ayada and general Rice-Tracey model work very well for the low triaxiality cases.

  7. Adaptive Linear Filtering Design with Minimum Symbol Error Probability Criterion

    Institute of Scientific and Technical Information of China (English)

    Sheng Chen

    2006-01-01

    Adaptive digital filtering has traditionally been developed based on the minimum mean square error (MMSE)criterion and has found ever-increasing applications in communications. This paper presents an alternative adaptive filtering design based on the minimum symbol error rate (MSER) criterion for communication applications. It is shown that the MSER filtering is smarter, as it exploits the non-Gaussian distribution of filter output effectively. Consequently, it provides significant performance gain in terms of smaller symbol error over the MMSE approach. Adopting Parzen window or kernel density estimation for a probability density function, a block-data gradient adaptive MSER algorithm is derived. A stochastic gradient adaptive MSER algorithm, referred to as the least symbol error rate, is further developed for sampleby-sample adaptive implementation of the MSER filtering. Two applications, involving single-user channel equalization and beamforming assisted receiver, are included to demonstrate the effectiveness and generality of the proposed adaptive MSER filtering approach.

  8. An important reference criterion for the selection of GSSP

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A study on the relationship between biostratigraphy and sequence stratigraphy in several designated global boundary stratotypes shows that the best way may be to take the GSSP at a point coincident with the base of the first widespread Leading Group biozone above the first flooding surface (FFS) of the relevant third-order sequence.It is suggested that the first flooding surface of the sequence should be an important reference criterion for the selection of GSSP.As the base of the first widespread Leading Group biozone chosen for the definition of GSSP could not be lower than the first flooding surface of the referred sequence,the latter surface may be an important criterion for the recognition and correlation of the chronostratigraphic boundaries.

  9. A New Improved Failure Criterion for Salt Rock Based on Energy Method

    Science.gov (United States)

    Hao, T. S.; Liang, W. G.

    2016-05-01

    A non-linear triple shear energy yield criterion for salt rock is presented in this paper. It is the development of the triple shear energy yield criterion, of which the Mohr-Coulomb criterion can be seen as a special case. The main factors affecting the primary strength of salt rock, such as the mean stress and the Lode angle, are considered in the non-linear triple shear energy yield criterion. The non-linear new criterion provides the non-linear change trend of salt strength both in the I 1- J 2 stress space and in the deviatoric plane. Comparative study between the non-linear criterion predictions and experimental results of salt rock shows that the non-linear triple shear energy yield criterion fits quite well with both conventional triaxial test data and the true triaxial test data. For Maha Sarakham salt, the predictive capability of the non-linear triple shear energy yield criterion is clearly better than that of some other criteria used by Sriapai, such as modified Lade criterion, 3-D Hoek, and Brown criterion, Drucker-Prager criterion et al. The availability of the non-linear triple shear energy yield criterion can also be confirmed by comparative analysis between theoretical values and experimental values for non-salt rocks. So the non-linear triple shear energy yield criterion is a general failure criterion for rocks fractured by shear stress.

  10. Study on the Macromesoscopic Yield Criterion of Concrete Material

    OpenAIRE

    Xia XiaoZhou; Zhang Qing; Jiang Qun; Xiao JianQiang

    2013-01-01

    In mesoscopy, the concrete material is a kind of composite consisting of mortar matrix, aggregate, and the interface between them. And the shape of aggregate is assumed to be spherical and the mortar matrix is supposed to satisfy the Drucker-Prager yield criterion. The energy density support function is introduced to reflect the yield surface of mortar matrix. In order to solve the nonderivability on the yield boundary, the function approximation series has been constructed to substitute for ...

  11. Criterion and incremental validity of the emotion regulation questionnaire

    OpenAIRE

    Christos A. Ioannidis; Siegling, A B

    2015-01-01

    Although research on emotion regulation (ER) is developing, little attention has been paid to the predictive power of ER strategies beyond established constructs. The present study examined the incremental validity of the Emotion Regulation Questionnaire (ERQ; Gross and John, 2003), which measures cognitive reappraisal and expressive suppression, over and above the Big Five personality factors. It also extended the evidence for the measure's criterion validity to yet unexamined criteria. A un...

  12. Criterion and Incremental Validity of the Emotion Regulation Questionnaire

    OpenAIRE

    Christos A. Ioannidis; Siegling, A B

    2015-01-01

    Although research on emotion regulation (ER) is developing, little attention has been paid to the predictive power of ER strategies beyond established constructs. The present study examined the incremental validity of the Emotion Regulation Questionnaire (ERQ; Gross & John, 2003), which measures cognitive reappraisal and expressive suppression, over and above the Big Five personality traits. It also extended the evidence for the measure’s criterion validity to yet unexamined criteria. A univ...

  13. Learning Theory Approach to Minimum Error Entropy Criterion

    OpenAIRE

    Hu, Ting; Fan, Jun; Wu, Qiang; Zhou, Ding-Xuan

    2012-01-01

    We consider the minimum error entropy (MEE) criterion and an empirical risk minimization learning algorithm in a regression setting. A learning theory approach is presented for this MEE algorithm and explicit error bounds are provided in terms of the approximation ability and capacity of the involved hypothesis space when the MEE scaling parameter is large. Novel asymptotic analysis is conducted for the generalization error associated with Renyi's entropy and a Parzen window function, to over...

  14. Toward an equivalence criterion for Hybrid RANS/LES methods

    OpenAIRE

    Friess, Christophe; Manceau, R.; Gatski, T.B.

    2015-01-01

    International audience A criterion is established to assess the equivalence between hybrid RANS/LES methods, called H-equivalence, based on the modeled energy of the unresolved scales, which leads to similar low-order statistics of the resolved motion. Different equilibrium conditions are considered, and perturbation analyses about the equilibrium states are performed. The procedure is applied to demonstrate the equivalence between two particular hybrid methods, and leads to relationships ...

  15. Large, moderate, small earthquakes and seismic fortification criterion

    Institute of Scientific and Technical Information of China (English)

    沈建文; 石树中

    2004-01-01

    This paper discusses the relation between two-step seismic design and the standard of probability of exceedance, and the relation of three-levels seismic ground motion parameters given by probability method and comprehensive probability method. The relative size relations of the ground motions with 2%, 10%, 63% probability of exceedance in 50 years, namely "large earthquake","moderate earthquake", and "small earthquake", are discussed through a practical example of seismic hazard analysis. The methods to determine seismic fortification criterion are discussed.

  16. Determining threshold default risk criterion for trade credit granting

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    To solve the problem of setting threshold default risk criterion to select retailer eligible for trade credit granting, a novel method of solving simultaneous equations is proposed. This method is based on the bilevel programming modeling of trade credit decisions as an interaction between supplier and retailer. First, the bilevel programming is set up where the supplier decides on credit terms at the top level considering a retailer's default risk, and the retailer determines the order quantity at the lowe...

  17. Smart Test Case Quantifier Using MC/DC Coverage Criterion

    Directory of Open Access Journals (Sweden)

    S. Shanmuga Priya

    2014-03-01

    Full Text Available Software testing, an important phase in Software Development Life Cycle (SDLC is a time consuming process. Information shows that nearly 40 to 50% of software development time is spent in testing. Manual testing is labour-intensive and error-prone so there is a need for automatic testing technique. Automation brings down the time and cost involved in testing. When testing software, there are often a massive amount of possible test-cases even for quite simple systems. Running each and every feasible test-case is certainly not a choice, so designing test-cases becomes a significant part of the testing process. NASA proposed Modified Condition/Decision Coverage (MC/DC testing criterion in 1994, which is a white box testing criterion. The objective of this paper is to automate the generation of minimum number of test cases required to test a system with maximum coverage by removing the redundant test cases using MC/DC criterion. The work also gives a tool Smart Test Case Generator Tool (STCGT that automates the minimum number of test cases required to test the source code. This will give an idea about the test cases execution for the beginners of the testing team, thereby, aids in a quality on-time product.

  18. Kinetic theory of the presheath and the Bohm criterion

    Science.gov (United States)

    Baalrud, S. D.; Hegna, C. C.

    2011-04-01

    A kinetic theory of the Bohm criterion is developed that is based on positive-exponent velocity moments of the plasma kinetic equation. This result is contrasted with the conventional kinetic Bohm criterion that is based on a v-1 moment of the Vlasov equation. The salient difference between the two results is that low-velocity particles dominate in the conventional theory, but are essentially unimportant in the new theory. It is shown that the derivation of the conventional kinetic Bohm criterion is flawed. Low-velocity particles can cause unphysical divergences in the conventional theory. These divergent contributions are avoided with this new approach. The two theories are compared using example distribution functions from previous presheath models. The importance of ion-ion and electron-electron collisions to determining the particle distribution functions throughout the presheath is also discussed. A kinetic equation that accounts for wave-particle scattering by convective instabilities is used to show that ion-acoustic instabilities in the presheath of low temperature plasmas (where Te Gt Ti) can cause both ions and electrons to obtain Maxwellian distribution functions near the sheath.

  19. Slitting criterion for various rolling speeds in MSR rolling process

    Directory of Open Access Journals (Sweden)

    A. Stefanik

    2008-03-01

    Full Text Available Purpose: The main idea of MSR technology is the capability of producing two, three, four and even five rods simultaneously from a single strip in a hot rolling process. Correctly separation of the joined strips is the one of the mainly problem in MSR process. Changing the rolling speed may causes easier of the strand division. In this paper results of the computer simulation of the double slitting rolling process were presented.Design/methodology/approach: For numerical modelling of the multi rolling process a computer program Forge 2005, based by the finished element method was used. As a slitting criterion normalised Cockroft – Latham criterion was used.Findings: For the analysis performed in this study, it was found that increasing of the rolling speed causes of increasing the normalized Cockroft – Latham criterion. For the small values of rolling velocity the strip separation was easier.Research limitations/implications: Multi Slit Rolling process is applied in ribbed rods rolling. Adjusting of the rolling speed in multi slit rolling process could improve of the slitting band to the separated strips.Originality/value: Incorrect construction or bad gap matching could cause lack of separation propelled slitting rolls. The separation of the band is effected by means of separating rollers, which shape must be properly designed to suit to the slitting pass. Changing of the rolling speed could improve of the separation to the single strips.

  20. Derivation of Plastic Work Rate Done per Unit Volume for Mean Yield Criterion and Its Application

    Institute of Scientific and Technical Information of China (English)

    Dewen ZHAO; Yingjie XIE; Xiaowen WANG; Xianghua LIU

    2005-01-01

    In Haigh Westergaard stress space linear combination of twin shear stress and Tresca yield functions is called the mean yield (MY) criterion. The mathematical relationship of the criterion and its plastic work rate done per unit volume were derived. A generalized worked example of slab forging was analyzed by the criterion and its corresponding plastic work rate done per unit volume. Then, the precision of the solution was compared with those by Mises and Twin shear stress yield criterions, respectively. It turned out that the calculated results by MY criterion were in good agreement with those by Mises criterion.

  1. Briggs, Henry (1561-1630)

    Science.gov (United States)

    Murdin, P.

    2000-11-01

    Mathematician, born in Worley Wood, Yorkshire, England. Professor at Cambridge, London (Gresham College) and Oxford. By pointing out how much more useful logarithms would be if (unlike JOHN NAPIER's original invention) they were to base 10, he was responsible for improving astronomers' ability to calculate. Published mathematical tables (logarithms, sines, tangents, secants) as an aid to such ca...

  2. On the sampling criterion for structural radiation in fluid.

    Science.gov (United States)

    Veronesi, Giorgio; Nijman, Eugène J M

    2016-05-01

    When experimentally investigating the sound radiating from vibrating structures the surface is discretised into elemental areas also referred to as patches in which the surface vibrations are considered uniform. In many cases the structural Nyquist criterion imposes very small patch sizes which turn the experimental analysis into an overwhelmingly elaborate and error-prone task. The possibility to use a coarse sampling scheme for the surface velocity can greatly enhance the practical feasibility of such experimental investigations. Here the special case of a simply supported baffled plate excited by a broadband point force is considered. It is shown that accurate approximations of the radiated power may be obtained well beyond the frequency limit imposed by the structural Nyquist sampling criterion, provided the complex-valued vibration field is averaged over each patch. This is due to the fact that the structural wave components with wavenumbers greater than the acoustic wavenumber tend to be averaged out, owing to the mutual canceling of areas which vibrate out-of-phase within each patch, leaving only those components that contribute significantly to the radiated sound. It turns out, however, that this canceling process is not complete and that an error is introduced by the spatial aliasing. An analytical expression is derived allowing one to quantify this error and to optimise the patch size given a desired accuracy level and frequency range for the assessment of the radiated power. The proposed sampling criterion not only allows one to significantly reduce the measurement efforts when the radiation of vibro-acoustic systems are experimentally investigated but can also be applied to reduce the size of numerical models for weakly coupled structural-acoustic systems. PMID:27250189

  3. Carbon emissions and an equitable emission reduction criterion

    International Nuclear Information System (INIS)

    In 1995 the world-wide carbon emissions reached 5.8 billion metric tonnes per year (GTC/y). The Kyoto protocol calls for a reduction of carbon emissions from the developed countries (Annex I countries) of 6-8% below 1990 levels on the average, and unspecified commitments for the less developed (non-Annex I) countries. It is doubtful that the Kyoto agreement will be ratified by some parliaments, especially the USA Congress. Furthermore, it is shown that if the non-Annex I countries will not curtail their carbon emissions drastically, the global emissions will soar to huge levels by the middle of the next century. An equitable emission criterion is proposed which may lead to a sustainable rate of growth of carbon emissions, and be acceptable to all countries of the world. The criterion links the rate of growth of carbon emissions to the rate of growth of the Gross Domestic Product (GDP). A target criterion is proposed R = 0.15 KgC/SGDP, which is the current average for western European countries and Japan. This allows for both the growth of the GDP and carbon emissions. However, to reach the target in a reasonable time, the countries for which R≤ 0.3 would be allowed a carbon emission growth rate of 1%./y, and countries for which R≥ 0.3, 0.75%/y. It is shown that by 2050 the world-wide carbon emissions would reach about 10 GTC/y, which is about 3 times less than the Kyoto agreement would allow. (Author)

  4. Application of the Kelly Criterion to Ornstein-Uhlenbeck Processes

    Science.gov (United States)

    Lv, Yingdong; Meister, Bernhard K.

    In this paper, we study the Kelly criterion in the continuous time framework building on the work of E.O. Thorp and others. The existence of an optimal strategy is proven in a general setting and the corresponding optimal wealth process is found. A simple formula is provided for calculating the optimal portfolio for a set of price processes satisfying some simple conditions. Properties of the optimal investment strategy for assets governed by multiple Ornstein-Uhlenbeck processes are studied. The paper ends with a short discus-sion of the implications of these ideas for financial markets.

  5. Landau theory and Ginzburg criterion for interacting bosons

    International Nuclear Information System (INIS)

    Starting with a microscopic Hamiltonian for a system of interacting bosons, and using perturbation theory, a Landau type theory is developed to describe the system in the vicinity of the Bose-Einstein transition curve. The theory is, however, seen to be valid only if the dimensionality d of the system is larger than 4; for d < 4, higher order graphs make divergent contributions. An attempt to remove the divergences in a self-consistent manner yields Ginzburg's criterion for the validity of the Landau theory. (author)

  6. An instability criterion for nonlinear standing waves on nonzero backgrounds

    CERN Document Server

    Jackson, R K; Susanto, H

    2012-01-01

    In this work, we study the standing wave solutions of an inhomogeneous nonlinear Schr\\"odinger equation. The inhomogeneity considered here is a varying coefficient of the nonlinear term. In particular, the nonlinearity is chosen to be repelling (defocusing) except on a finite interval. Localized solutions on a non-zero background, e.g. dark solitons trapped by the inhomogeneity, are identified and studied. A novel instability criterion for such states is established through a topological argument. This allows instability to be determined quickly in many cases by considering simple geometric properties of the standing waves as viewed in the composite phase plane. Numerical calculations accompany the analytical results.

  7. Adjustment Criterion and Algorithm in Adjustment Model with Uncertain

    Directory of Open Access Journals (Sweden)

    SONG Yingchun

    2015-02-01

    Full Text Available Uncertainty often exists in the process of obtaining measurement data, which affects the reliability of parameter estimation. This paper establishes a new adjustment model in which uncertainty is incorporated into the function model as a parameter. A new adjustment criterion and its iterative algorithm are given based on uncertainty propagation law in the residual error, in which the maximum possible uncertainty is minimized. This paper also analyzes, with examples, the different adjustment criteria and features of optimal solutions about the least-squares adjustment, the uncertainty adjustment and total least-squares adjustment. Existing error theory is extended with new observational data processing method about uncertainty.

  8. The alternative DSM-5 personality disorder traits criterion

    DEFF Research Database (Denmark)

    Bach, Bo; Maples-Keller, Jessica L; Bo, Sune;

    2016-01-01

    The fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5; American Psychiatric Association, 2013a) offers an alternative model for Personality Disorders (PDs) in Section III, which consists in part of a pathological personality traits criterion measured...... with the Personality Inventory for DSM-5 (PID-5). The PID-5 selfreport instrument currently exists in the original 220-item form, a short 100-item form, and a brief 25-item form. For clinicians and researchers, the choice of a particular PID- 5 form depends on feasibility, but also reliability and validity. The goal...

  9. Forecastability as a Design Criterion in Wind Resource Assessment: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, J.; Hodge, B. M.

    2014-04-01

    This paper proposes a methodology to include the wind power forecasting ability, or 'forecastability,' of a site as a design criterion in wind resource assessment and wind power plant design stages. The Unrestricted Wind Farm Layout Optimization (UWFLO) methodology is adopted to maximize the capacity factor of a wind power plant. The 1-hour-ahead persistence wind power forecasting method is used to characterize the forecastability of a potential wind power plant, thereby partially quantifying the integration cost. A trade-off between the maximum capacity factor and the forecastability is investigated.

  10. Shear velocity criterion for incipient motion of sediment

    Directory of Open Access Journals (Sweden)

    Francisco J. M. SIMÕES

    2014-04-01

    Full Text Available The prediction of incipient motion has had great importance to the theory of sediment transport. The most commonly used methods are based on the concept of critical shear stress and employ an approach similar, or identical, to the Shields diagram. An alternative method that uses the movability number, defined as the ratio of the shear velocity to the particle’s settling velocity, was employed in this study. A large amount of experimental data were used to develop an empirical incipient motion criterion based on the movability number. It is shown that this approach can provide a simple and accurate method of computing the threshold condition for sediment motion.

  11. Regularity criterion for the 3D Hall-magneto-hydrodynamics

    Science.gov (United States)

    Dai, Mimi

    2016-07-01

    This paper studies the regularity problem for the 3D incompressible resistive viscous Hall-magneto-hydrodynamic (Hall-MHD) system. The Kolmogorov 41 phenomenological theory of turbulence [14] predicts that there exists a critical wavenumber above which the high frequency part is dominated by the dissipation term in the fluid equation. Inspired by this idea, we apply an approach of splitting the wavenumber combined with an estimate of the energy flux to obtain a new regularity criterion. The regularity condition presented here is weaker than conditions in the existing criteria (Prodi-Serrin type criteria) for the 3D Hall-MHD system.

  12. SOCIO-PSYCHOLOGICAL CRITERIONS OF FAMILY LIFESTYLE TYPOLOGY

    OpenAIRE

    Yekaterina Anatolievna Yumkina

    2015-01-01

    The purpose of this article is to present socio-psychological criterions of family lifestyle typology, which were found during theoretical modelling and empirical research work. It is important in fundamental and practical aspects. St-Petersburg students (n = 116, from 19 to 21 years old) were examined by special questionnaire «Family relationship and home» (Kunitsi-na V.N., Yumkina Ye.A., 2012) which measures different aspects of family lifestyle. We also used complex of methods that gave us...

  13. Sensor Calibration Design Based on D-Optimality Criterion

    Directory of Open Access Journals (Sweden)

    Hajiyev Chingiz

    2016-09-01

    Full Text Available In this study, a procedure for optimal selection of measurement points using the D-optimality criterion to find the best calibration curves of measurement sensors is proposed. The coefficients of calibration curve are evaluated by applying the classical Least Squares Method (LSM. As an example, the problem of optimal selection for standard pressure setters when calibrating a differential pressure sensor is solved. The values obtained from the D-optimum measurement points for calibration of the differential pressure sensor are compared with those from actual experiments. Comparison of the calibration errors corresponding to the D-optimal, A-optimal and Equidistant calibration curves is done.

  14. Criterion for SLOCC equivalence of multipartite quantum states

    Science.gov (United States)

    Zhang, Tinggui; Zhao, Ming-Jing; Huang, Xiaofen

    2016-10-01

    We study the stochastic local operation and classical communication (SLOCC) equivalence for arbitrary dimensional multipartite quantum states. For multipartite pure states, we present a necessary and sufficient criterion in terms of their coefficient matrices. This condition can be used to classify some SLOCC equivalent quantum states with coefficient matrices having the same rank. For multipartite mixed state, we provide a necessary and sufficient condition by means of the realignment of matrix. Some detailed examples are given to identify the SLOCC equivalence of multipartite quantum states.

  15. Recent Innovations in the Changing Criterion Design: Implications for Research and Practice in Special Education

    Science.gov (United States)

    McDougall, Dennis; Hawkins, Jacqueline; Brady, Michael; Jenkins, Amelia

    2006-01-01

    This article illustrates (a) 2 recent innovations in the changing criterion research design, (b) how these innovations apply to research and practice in special education, and (c) how clinical needs influence design features of the changing criterion design. The first innovation, the range-bound changing criterion, is a very simple variation of…

  16. An objective criterion for determining the South Atlantic Convergence Zone

    Directory of Open Access Journals (Sweden)

    Tercio eAmbrizzi

    2015-04-01

    Full Text Available The South Atlantic Convergence Zone (SACZ is the dominant summertime cloudiness feature of subtropical South America and the western South Atlantic Ocean, having a significant influence on the precipitation regime of southeastern Brazil. This paper proposes an objective criterion based mainly on precipitation, as this variable is easily obtained on general circulation models simulating past, present and future climate. Usually most SACZ studies use emerging long wave radiation as a precipitation proxy. This is enough to describe event position at first, but using precipitation would allow for better quantification, especially for climate studies, where precipitation is indispensable. An assessment was carried out to find out if classical DJF period is ideal for determining the SACZ for the present climate and future scenarios. In general the SACZ event detection criterion showed quite satisfactory results when event dates were previously known. When it was applied to future climate scenario it identified a number of events compatible with the present climate. The SACZ was well defined for both the simulated and observed precipitation data.

  17. Asymmetry in olfactory generalization and the inclusion criterion in ants.

    Science.gov (United States)

    Bos, Nick

    2014-01-01

    Animals constantly face the challenge of extracting important information out of their environment, and for many animals much of this information is chemical in nature. The ability to discriminate and generalize between chemical stimuli is extremely important and is commonly thought to depend mostly on the structural similarity between the different stimuli. However, we previously provided evidence that in the carpenter ant Camponotus aethiops, generalization not only depends on structural similarity, but also on the animal's previous training experience. When individual ants were conditioned to substance A, they generalized toward a mixture of A and B. However, when trained to substance B, they did not generalize toward this mixture, resulting in asymmetrical generalization. This asymmetry followed an inclusion criterion, where the ants consistently generalized from a molecule with a long carbon chain to molecules with a shorter chain, but not the other way around. Here I will review the evidence for the inclusion criterion, describe possible proximate mechanisms underlying this phenomenon as well as discuss its potential adaptive significance. PMID:25346797

  18. Karst Collapse Mechanism and Criterion for Its Stability

    Institute of Scientific and Technical Information of China (English)

    贺可强; 刘长礼; 王思敬

    2001-01-01

    Karst collapse, caused by natural or artificial abstraction of groundwater, has been a focus of environmental geological problems for its ever-increasing hazardousness. The potential erosion theory and vacuum suction erosion theory,which reveal the origin of karst collapse macroscopically, are popularly accepted. However, a mathematic prediction criterion for karst collapse cannot be established only by these two theories. From a new perspective, this paper attempts to explain the microcosmic mechanism of karst collapse on the basis of these two theories. When the shear stress surpasses the shear strength of soil, a certain point or a certain plane in the unconsolidated soil covering karst caves will fail under the mechanical effects of water and air as well as its load-pressure, and with the increase of damaged points, a breaking plane appears and the soil on karst caves is completely damaged; as a result, the karst ground collapses. On the basis of the MohrCoulomb failure theory and previous studies, the paper presents a prediction criterion of karst collapse. Finally, by taking,for example, nine typical cases of collapse caused by pumping tests in Guizhou, the paper gives the calculation process of the model and proves its reliability.``

  19. Job shop scheduling problem with late work criterion

    Science.gov (United States)

    Piroozfard, Hamed; Wong, Kuan Yew

    2015-05-01

    Scheduling is considered as a key task in many industries, such as project based scheduling, crew scheduling, flight scheduling, machine scheduling, etc. In the machine scheduling area, the job shop scheduling problems are considered to be important and highly complex, in which they are characterized as NP-hard. The job shop scheduling problems with late work criterion and non-preemptive jobs are addressed in this paper. Late work criterion is a fairly new objective function. It is a qualitative measure and concerns with late parts of the jobs, unlike classical objective functions that are quantitative measures. In this work, simulated annealing was presented to solve the scheduling problem. In addition, operation based representation was used to encode the solution, and a neighbourhood search structure was employed to search for the new solutions. The case studies are Lawrence instances that were taken from the Operations Research Library. Computational results of this probabilistic meta-heuristic algorithm were compared with a conventional genetic algorithm, and a conclusion was made based on the algorithm and problem.

  20. ACTION AS A CRITERION OF THE CAR OPERATING EFFECTIVENES

    Directory of Open Access Journals (Sweden)

    Stefan POSTRZEDNIK

    2016-06-01

    Full Text Available Currently used criteria for determining car operating efficiency in road traffic are, among others, emission of harmful substances, consumption of engine driving fuels, technical service and reliability of operation, safety of use. The operational characteristics of the car in terms of engine driving fuel consumption data is usually recognised as so-called road specific fuel consumption. An important deficiency of this approach is the failure to take into account the influence of the time on the journey’s effectiveness and the final result of the entire project. To obtain a new solution in this range in the analysis, a quantity called "action", which at last will be treated as the criterion of the car operating effectiveness, was used. The quantity of action is the product of the performed work and its realisation time. Many phenomena and processes in nature take place according to the principle of "minimum of action"  this criterion can be applied in the analysis of the car’s operating efficiency taking place in road traffic. An approach of this issue is presented in this article, wherein the basic data for analysis were obtained in the framework of the car tests performed at the real traffic conditions.

  1. Asymmetry in olfactory generalization and the inclusion criterion in ants.

    Science.gov (United States)

    Bos, Nick

    2014-01-01

    Animals constantly face the challenge of extracting important information out of their environment, and for many animals much of this information is chemical in nature. The ability to discriminate and generalize between chemical stimuli is extremely important and is commonly thought to depend mostly on the structural similarity between the different stimuli. However, we previously provided evidence that in the carpenter ant Camponotus aethiops, generalization not only depends on structural similarity, but also on the animal's previous training experience. When individual ants were conditioned to substance A, they generalized toward a mixture of A and B. However, when trained to substance B, they did not generalize toward this mixture, resulting in asymmetrical generalization. This asymmetry followed an inclusion criterion, where the ants consistently generalized from a molecule with a long carbon chain to molecules with a shorter chain, but not the other way around. Here I will review the evidence for the inclusion criterion, describe possible proximate mechanisms underlying this phenomenon as well as discuss its potential adaptive significance.

  2. PET image reconstruction: mean, variance, and optimal minimax criterion

    Science.gov (United States)

    Liu, Huafeng; Gao, Fei; Guo, Min; Xue, Liying; Nie, Jing; Shi, Pengcheng

    2015-04-01

    Given the noise nature of positron emission tomography (PET) measurements, it is critical to know the image quality and reliability as well as expected radioactivity map (mean image) for both qualitative interpretation and quantitative analysis. While existing efforts have often been devoted to providing only the reconstructed mean image, we present a unified framework for joint estimation of the mean and corresponding variance of the radioactivity map based on an efficient optimal min-max criterion. The proposed framework formulates the PET image reconstruction problem to be a transformation from system uncertainties to estimation errors, where the minimax criterion is adopted to minimize the estimation errors with possibly maximized system uncertainties. The estimation errors, in the form of a covariance matrix, express the measurement uncertainties in a complete way. The framework is then optimized by ∞-norm optimization and solved with the corresponding H∞ filter. Unlike conventional statistical reconstruction algorithms, that rely on the statistical modeling methods of the measurement data or noise, the proposed joint estimation stands from the point of view of signal energies and can handle from imperfect statistical assumptions to even no a priori statistical assumptions. The performance and accuracy of reconstructed mean and variance images are validated using Monte Carlo simulations. Experiments on phantom scans with a small animal PET scanner and real patient scans are also conducted for assessment of clinical potential.

  3. A risk-based cleanup criterion for PCE in soil

    International Nuclear Information System (INIS)

    The most important attribute of a chemical contaminant at a hazardous-wastes site for decision makers to consider with regard to its cleanup is the potential risk associated with human exposure. For this reason we have developed a strategy for establishing a risk-based cleanup criterion for chemicals in soil. We describe this strategy by presenting a cleanup criterion for tetrachloroethylene (PCE) in soil associated with a representative California landscape. We being by discussing the environmental fate and transport model, developed at the Lawrence Livermore National Laboratory (LLNL), that we used to predict the equilibrium concentration of PCE in five environmental media from a steady-state source in soil. Next, we explain the concept and application of pathway-exposure factors (PEFs), the hazard index, and cancer-potency factors (CPFs) for translating the predicted concentrations of PCE into estimated potential hazard or risk for hypothetically exposed individuals. Finally, the relationship between concentration and an allowable level of risk is defined and the societal and financial implications are discussed. 22 refs., 6 tabs

  4. Criterion Related Validity of Karate Specific Aerobic Test (KSAT

    Directory of Open Access Journals (Sweden)

    Chaabene

    2015-09-01

    Full Text Available Background Karate is one the most popular combat sports in the world. Physical fitness assessment on a regular manner is important for monitoring the effectiveness of the training program and the readiness of karatekas to compete. Objectives The aim of this research was to examine the criterion related to validity of the karate specific aerobic test (KSAT as an indicator of aerobic level of karate practitioners. Patients and Methods Cardiorespiratory responses, aerobic performance level through both treadmill laboratory test and YoYo intermittent recovery test level 1 (YoYoIRTL1 as well as time to exhaustion in the KSAT test (TE’KSAT were determined in a total of fifteen healthy international karatekas (i.e. karate practitioners (means ± SD: age: 22.2 ± 4.3 years; height: 176.4 ± 7.5 cm; body mass: 70.3 ± 9.7 kg and body fat: 13.2 ± 6%. Results Peak heart rate obtained from KSAT represented ~99% of maximal heart rate registered during the treadmill test showing that KSAT imposes high physiological demands. There was no significant correlation between KSAT’s TE and relative (mL/min kg treadmill maximal oxygen uptake (r = 0.14; P = 0.69; [small]. On the other hand, there was a significant relationship between KSAT’s TE and the velocity associated with VO2max (vVO2max (r = 0.67; P = 0.03; [large] as well as the velocity at VO2 corresponding to the second ventilatory threshold (vVO2 VAT (r = 0.64; P = 0.04; [large]. Moreover, significant relationship was found between TE’s KSAT and both the total distance covered and parameters of intermittent endurance measured through YoYoIRTL1. Conclusions The KSAT has not proved to have indirect criterion related validity as no significant correlations have been found between TE’s KSAT and treadmill VO2max. Nevertheless, as correlated to other aerobic fitness variables, KSAT can be considered as an indicator of karate specific endurance. The establishment of the criterion related validity of the

  5. Energy Criterion of Oil Film Failure during Friction

    Directory of Open Access Journals (Sweden)

    S.V. Fedorov

    2014-12-01

    Full Text Available The concepts developed by the thermodynamic theory of solid body strength and fracture are used to examine the conditions of lubricant film failure. We obtain a quantitative criterion that defines the lubricant film "defectness" - the critical value (constant for a given mineral oil of the internal (thermal energy density in the volume of the lubricant film. We propose analytic relations for evaluating scuffing in friction with lubrication and verify them experimentally on a full-scale stand for testing actual sliding bearings. We show the constancy of the critical value of the internal (thermal energy density in the volume of the oil film at the moment of scuffing for an inactive mineral oil.

  6. Criterion and Incremental Validity of the Emotion Regulation Questionnaire

    Directory of Open Access Journals (Sweden)

    Christos A. Ioannidis

    2015-03-01

    Full Text Available Although research on emotion regulation (ER is developing, little attention has been paid to the predictive power of ER strategies beyond established constructs. The present study examined the incremental validity of the Emotion Regulation Questionnaire (ERQ; Gross & John, 2003, which measures cognitive reappraisal and expressive suppression, over and above the Big Five personality traits. It also extended the evidence for the measure’s criterion validity to yet unexamined criteria. A university student sample (N = 203 completed the ERQ, a measure of the Big Five, and relevant cognitive and emotion-laden criteria. Cognitive reappraisal predicted positive affect beyond personality, as well as experiential flexibility and constructive self-assertion beyond personality and affect. Expressive suppression explained incremental variance in negative affect beyond personality and in experiential flexibility beyond personality and general affect. No incremental effects were found for worry, social anxiety, rumination, reflection, and preventing negative emotions. Implications for the construct validity and utility of the ERQ are discussed.

  7. Optimal-sampling Active Interference Cancellation under the Minimax Criterion

    Directory of Open Access Journals (Sweden)

    Jinping Liu

    2014-05-01

    Full Text Available In industry and academia, researchers have given more and more attention to Cognitive Radio (CR. The key idea of CR is to make it possible for a wireless system to find the vacant spectrum and transfer data without interfering with licensed users (LUs. Then, OFDM is proposed as a candidate signaling technology for such applications. However, the sidelobe interference of subcarriers has become a problem. In this letter, a method for sidelobe suppressing in OFDM systems is proposed and investigated. The proposed method is based on sampling in optimal locations with optimal weights in Active Interference Cancellation (AIC. By means of this technique, the maximum interference of the target spectrum is minimized. The proposed method can be used to minimize the maximum interference to licensed users in OFDM-based cognitive radio systems. Additionally, this method can be combined with other algorithms, such as Cancellation Carriers (CCs and Subcarrier Weighting (SW, to enhance their performance under the minimax criterion.

  8. QV modal distance displacement - a criterion for contingency ranking

    Energy Technology Data Exchange (ETDEWEB)

    Rios, M.A.; Sanchez, J.L.; Zapata, C.J. [Universidad de Los Andes (Colombia). Dept. of Electrical Engineering], Emails: mrios@uniandes.edu.co, josesan@uniandes.edu.co, cjzapata@utp.edu.co

    2009-07-01

    This paper proposes a new methodology using concepts of fast decoupled load flow, modal analysis and ranking of contingencies, where the impact of each contingency is measured hourly taking into account the influence of each contingency over the mathematical model of the system, i.e. the Jacobian Matrix. This method computes the displacement of the reduced Jacobian Matrix eigenvalues used in voltage stability analysis, as a criterion of contingency ranking, considering the fact that the lowest eigenvalue in the normal operation condition is not the same lowest eigenvalue in N-1 contingency condition. It is made using all branches in the system and specific branches according to the IBPF index. The test system used is the IEEE 118 nodes. (author)

  9. Some remarks on Relativistic Diffusion and the Spectral Dimension Criterion

    CERN Document Server

    Muniz, C R; Filho, R N Costa; Bezerra, V B

    2014-01-01

    The spectral dimension $d_s$ for high energies is calculated using the Relativistic Schr\\"{o}dinger Equation Analytically Continued (RSEAC) instead of the so-called Telegraph's Equation (TE), in both ultraviolet (UV) and infrared (IR) regimens. Regarding the TE, the recent literature presents difficulties related to its stochastic derivation and interpretation, advocating the use of the RSEAC to properly describe the relativistic diffusion phenomena. Taking into account that the Lorentz symmetry is broken in UV regime at Lifshitz point, we show that there exists a degeneracy in very high energies, meaning that both the RSEAC and the TE correctly describe the diffusion processes at these energy scales, at least under the spectral dimension criterion. In fact, both the equations yield the same result, namely, $d_s = 2$, a dimensional reduction that is compatible with several theories of quantum gravity. This result is reached even when one takes into account a cosmological model - the De Sitter one - for a flat...

  10. SME Support Programs in Europe: Granting and Evaluation criterion

    Directory of Open Access Journals (Sweden)

    Antonia Madrid Guijarro

    2005-02-01

    Full Text Available The aim of this paper is to analyze the situation of the support programs to SME in Europe. We identify the main support programs to this kind of firms and analyze the general criterion used to grant and evaluate these programs by the different agencies using a phone survey. Our sample is formed by 44 agencies included in EURADA which represent a coverage of 33,3%. The result show that the support program that will be increased in a higher number of agencies is the one related to "innovation and technological development", and the one that will be decreased in a higher number of agencies is the one related to "reestructuration of declining firms".

  11. An Improved Ductile Fracture Criterion for Fine-blanking Process

    Institute of Scientific and Technical Information of China (English)

    ZHAO Zhen; ZHUANG Xin-cun; XIE Xiao-long

    2008-01-01

    In order to accurately simnulate the fine-blanking process,a suitable ductile fracture is significant.So an evaluation strategy based on experimental and corresponding simulation results of tensile,compression,torsion and fine-blanking test is designed to evaluate five typical ductile fracture criteria,which are widely-used in metal forming process.The stress triaxiality and ductile damage of each test specimen are analyzed.The results show that none of these five criteria is sufficient for all tests.Furthermore,an improved fracture criterion based on Rice and Tracey model,taking the influence of both volume change and shape change of voids into account,is proposed.The characterization of this model for fine-blanking process is easily done by the tensile test and the prediction result shows good.

  12. New criterion of material resistance for brittle fracture

    Directory of Open Access Journals (Sweden)

    M. Maj

    2010-01-01

    Full Text Available Wide variety of cast material applications and efforts to find optimum fields for casting operation are the reasons why it is so important to collect as many data on the properties of materials as possible. The problem of primary importance is to know how these materials will behave under the normally and rapidly changing loads, in other words – to know their fatigue strength. This study gives a short characteristic of fatigue tests and compares various data collected during measurements of the low-cycle fatigue strength coefficient K with the values of constant KIc, representing fracture toughness. The results of the investigations described here have revealed some important correlations that exist between the total elongation A5 and the proposed brittleness criterion B, conventional stress K, and fracture toughness KIc. The development of measurements seems to be of great importance and opens the field for further studies on practical implementation of this method.

  13. Preliminary Studies for Three Experiments at Treiman-Yang Criterion

    Science.gov (United States)

    Kres, I. V.; Kondratyev, V. N.; Cherubini, S.; Spitaleri, C.

    2016-05-01

    Nuclear reactions with three bodies in their final state may proceed through different reaction mechanisms. The Feynman graph technique has been widely used to describe such reactions. However, it is very difficult in general to select the graphs that dominate in given process. The Treiman-Yang criterion is one of the most powerful experimental tests for verifying the pole approximation prediction when describing a quasi-free reaction mechanism. We propose the theoretical study of the H2(B10, α Be7)ns, H1(B11, α1α2)αs, He3(Be9, α1α2)αs reactions at different energies. The preliminary study helps to check the existence of a QF channel by using the TY creterion.

  14. PRINCIPLE OF PROPORTIONALITY, CRITERION OF LEGITIMACY IN THE PUBLIC LAW

    Directory of Open Access Journals (Sweden)

    MARIUS ANDREESCU

    2011-04-01

    Full Text Available A problem of essence of the state is the one to delimit the discretionary power, respectively the power abuse in the activity of the state’s institutions. The legal behavior of the state’s institutions consists in their right to appreciate them and the power excess generates the violation of a subjective right or of the right that is of legitimate interest to the citizen. The application and nonobservance of the principle of lawfulness in the activities of the state is a complex problem because the exercise of the state’s functions assumes the discretionary powers with which the states authorities are invested, or otherwise said the ‘right of appreciation” of the authorities regarding the moment of adopting the contents of the measures proposed. The discretionary power cannot be opposed to the principle of lawfulness, as a dimension of the state de jure. In this study we propose to analyze the concept of discretionary power, respectively the power excess, having as a guidance the legislation, jurisprudence and doctrine in the matter. At the same time we would like to identify the most important criterions that will allow the user, regardless that he is or not an administrator, a public clerk or a judge, to delimit the legal behavior of the state’s institutions from the power excess. Within this context, we appreciate that the principle of proportionality represents such a criterion. The proportionality is a legal principle of the law, but at the same time it is a principle of the constitutional law and of other law branches. It expresses clearly the idea of balance, reasonability but also of adjusting the measures ordered by the state’s authorities to the situation in fact, respectively to the purpose for which they have been conceived. In our study we choose theoretical and jurisprudence arguments according to which the principle of proportionality can procedurally be determined and used to delimit the discretionary power and

  15. PRINCIPLE OF PROPORTIONALITY, CRITERION OF LEGITIMACY IN THE PUBLIC LAW

    Directory of Open Access Journals (Sweden)

    Marius ANDREESCU

    2011-08-01

    Full Text Available A problem of essence of the state is the one to delimit the discretionary power, respectively the power abuse in the activity of the state’s institutions. The legal behavior of the state’s institutions consists in their right to appreciate them and the power excess generates the violation of a subjective right or of the right that is of legitimate interest to the citizen. The application and nonobservance of the principle of lawfulness in the activities of the state is a complex problem because the exercise of the state’s functions assumes the discretionary powers with which the states authorities are invested, or otherwise said the ‘right of appreciation” of the authorities regarding the moment of adopting the contents of the measures proposed. The discretionary power cannot be opposed to the principle of lawfulness, as a dimension of the state de jure. In this study we propose to analyze the concept of discretionary power, respectively the power excess, having as a guidance the legislation, jurisprudence and doctrine in the matter. At the same time we would like to identify the most important criterions that will allow the user, regardless that he is or not an administrator, a public clerk or a judge, to delimit the legal behavior of the state’s institutions from the power excess. Within this context, we appreciate that the principle of proportionality represents such a criterion. The proportionality is a legal principle of the law, but at the same time it is a principle of the constitutional law and of other law branches. It expresses clearly the idea of balance, reasonability but also of adjusting the measures ordered by the state’s authorities to the situation in fact, respectively to the purpose for which they have been conceived. In our study we choose theoretical and jurisprudence arguments according to which the principle of proportionality can procedurally be determined and used to delimit the discretionary power and

  16. Limiting drainage criterion for groundwater of mountain tunnel

    Institute of Scientific and Technical Information of China (English)

    程盼; 赵炼恒; 李亮; 邹金锋; 罗伟

    2014-01-01

    Large amount of groundwater discharging from tunnel is likely to cause destruction of the ecological environment in the vicinity of the tunnel, thus an appropriate drainage criterion should be established to balance the tunnel construction and groundwater. To assess the related problems, an limiting drainage standard ranging from 0.5 to 2.0 m3/(m·d) was suggested for mountain tunnels based on survey and comparative analysis. After that, for the purpose of verifying the rationality of the standard, a calculated formula for dewatering funnel volume caused by drainage was deduced on the basis of the groundwater dynamics and experience method. Furthermore, the equation about the relationship between water discharge and drawdown of groundwater table was presented. The permeability coefficient, specific yield and groundwater table value were introduced, and then combined with the above equation, the drawdown of groundwater table under the proposed limiting drainage criterion was calculated. It is shown that the proposed drainage standard can reach the purpose of protecting ecological environment under the following two conditions. One is the permeability coefficient ranges from 10−4 to 10−5 m/s and the specific yield ranges from 0.1 to 0.001. The other is the permeability coefficient varies from 10−6 to 10−8 m/s and the specific yield varies from 0.1 to 0.01. In addition, a majority of common geotechnical layers are involved in the above ranges. Thus, the proposed limiting drainage standard which ranges from 0.5 to 2.0 m3/(m·d) for mountain tunnel is reasonable.

  17. Criterions of UT thickness measurement on thinned pipe management program

    International Nuclear Information System (INIS)

    Wall thinning of carbon steel pipe components due to flow-accelerated corrosion (FAC) is one of the most serious threats to the integrity of steam cycle piping systems in Nuclear Power Plants (NPP). If the thickness of a pipe component is reduced below the critical level, it cannot sustain stress and consequently results in leakage or rupture. Since the mid-1990s, secondary side piping systems in Korean NPPs have experienced wall thinning, leakages and ruptures caused by FAC. Korea Electric Power Research Institute (KEPRI) and Korea Hydro and Nuclear Power Co., LTD. (KHNP) have conducted a study to develop the methodology for systematic pipe management and as a result, established the Korean thinned pipe management program (TPMP) which is being implemented to all Korean NPPs. TPMP consists of several technical elements such as prediction of the FAC rate for each component based on model analysis, prioritization of pipe components for inspection, thickness measurement, calculation of wear and wear rate for each component. Additionally, decision making associated with replacement or continuous service for thinned pipe components and establishment of long-term strategic management plan based on diagnosis of plant condition regarding overall wall thinning also are essential part of the TPMP. To effectively monitor and manage the thinning pipe components, NDE person as well as FAC engineer should understand the criterions of ultrasonic thickness measurement and there background. This paper describes the technical items of TPMP and the basis of thickness measurement criterions. This paper also shows the initial thickness variations which influence wear and wear rate calculations to obtain the reasonable integrity assessment results. (orig.)

  18. A new cladding embrittlement criterion derived from ring compression tests

    Energy Technology Data Exchange (ETDEWEB)

    Herb, Joachim, E-mail: Joachim.Herb@grs.de; Sievers, Jürgen, E-mail: Juergen.Sievers@grs.de; Sonnenburg, Heinz-Günther, E-mail: Heinz-Guenther.Sonnenburg@grs.de

    2014-07-01

    Highlights: • Using FEM it was possible to simulate measured ring compression test data. • The FEM provides burst stresses from Zry-4, M5 and ZIRLO cladding. • The ratio of burst stresses to yield stresses was correlated. • The ratio depends linearly on the state of oxidation and hydriding. • The ratio of stresses at unity can be applied as embrittlement criterion. - Abstract: It is of regulatory interest to prevent the breaking of fuel rods in LOCA transients. In current regulations this is accomplished by limiting the oxidation during LOCA to such an extent that still some residual ductility is preserved in the fuel rod cladding. The current oxidation limit in German as well as in US regulations is set to 17% ECR (Equivalent Cladding Reacted) which aims at maintaining a residual ductility for oxidized claddings. Recent ANL tests have shown that the combination of both oxidation and additionally hydrogen up-take affects the transition to zero-ductility. Furthermore, the oxidation during LOCA transient is accompanied by a significant up-take of hydrogen (secondary hydriding) if the fuel rod bursts during this transient. This secondary hydriding affects the cladding in the vicinity of the burst opening. These findings necessitate a new criterion for preserving cladding's strength. This paper describes a method how to derive a criterion which assures the required residual mechanical strength of the cladding for LOCA transients. This method utilizes the experimental results of 102 ring compression tests (RCT) conducted at ANL and KIT. RCTs of various cladding materials, oxidation levels and hydrogen content were considered. The basic approach was to compare the RCT test data with finite element analyses using the code ADINA. Starting with the cladding oxidation model of Leistikov, both the layer structure of the cladding and the distribution of the oxygen among these layers were determined. The mechanical properties of these layers were taken from

  19. Validation of Hoek-Brown failure criterion charts for rock slopes

    Institute of Scientific and Technical Information of China (English)

    A.M. Nekouei; K. Ahangari

    2013-01-01

    Although stability charts suggested by Hoek and Bray on the basis of Mohr-Coulomb criterion are used for rock slopes, but complete and precise recognition is required for distinguishing cohesive strength and Mohr-Coulomb equivalent internal friction angle for rock mass. The paper by Lia et al. [6] is the only one that introduced rock slope charts according to Hoek-Brown failure criterion. In this paper, at first, this type of charts is introduced. Then, Mohr-Coulomb failure criterion charts [2] are compared and validated with Hoek-Brown failure criterion ones [6]. Next, Bishop method utilizing Slide software is compared with Hoek-Brown failure criterion stability charts. Average standard deviation (ASD), root mean square error (RMSE) and variance account for (VAF) were used for the comparison. According to the results, because of high distribution and very low correlation among the comparisons, Hoek-Brown failure crite-rion charts are not efficient.

  20. An optimality criterion for sizing members of heated structures with temperature constraints. [considering aerospace structures

    Science.gov (United States)

    Rao, G. V.; Shore, C. P.; Narayanaswami, R.

    1977-01-01

    A thermal optimality criterion is presented for sizing members of heated structures with multiple temperature constraints. The optimality criterion is similar to an existing optimality criterion for design of mechanically loaded structures with displacement constraints. Effectiveness of the thermal optimality criterion is assessed by applying it to one- and two-dimensional thermal problems where temperatures can be controlled by varying the material distribution in the structure. Results obtained from the optimality criterion agree within 2 percent with results from a closed-form solution and with results from a mathematical programming technique. The thermal optimality criterion augments existing optimality criteria for strength and stiffness related constraints and offers the possibility of extension of optimality techniques to sizing structures with combined thermal and mechanical loading.

  1. ICF Ignition, the Lawson Criterion, and Comparison with MFE Ignition

    Science.gov (United States)

    Betti, R.

    2009-11-01

    The Lawson criterion, which determines the onset of thermonuclear ignition, is usually expressed through the product pτ > 10 atm . s, where p is the plasma pressure in atm and τ is the energy confinement time in seconds. In magnetic fusion devices, both the pressure and confinement time are routinely measured and the performance of each discharge can be assessed by comparing the value of pτ with respect to the ignition value (10 atm . s). In inertial confinement fusion, both p and τ cannot be directly measured and the performance of surrogate and/or subignited ICF implosions cannot be assessed with respect to the ignition condition. This makes it difficult to compare the performance of ICF implosions with that of magnetic fusion energy (MFE) discharges. Here, we define the meaning of ignition in ICF implosions and compare it to MFE ignition. We then show that a multidimensional ignition condition for inertial confinement fusion can be cast in a form that depends on three measurable parameters of the compressed-fuel assembly: the hot-spot ion temperature T, the neutron yield normalized to the 1-D prediction (yield over clean or YOC) and the total areal density ρR, which includes the cold shell's contribution. A family of marginal-ignition curves are derived in the ρR--T plane.footnotetext C. D. Zhou and R. Betti, Phys. Plasmas 15, 102707 (2008). On this plane, hydrodynamic-equivalent curves show how a given implosion would perform with respect to the ignition condition when the laser-driver energy is varied. Such a criterion can be used to measure the ignition marginfootnotetext D. S. Clark, S. W. Haan, and J. D. Salmonson, Phys. Plasmas 15, 056305 (2008). of NIF targets and to predict the performance of OMEGA targets when scaled up to NIF energies. This work has been supported by the US Department of Energy under Cooperative Agreement Nos. DE-FC02-ER54789 and DE-FC52-08NA28302.

  2. Probability Criterion for a Dynamic Financial Model with Short-Selling Allowed

    Institute of Scientific and Technical Information of China (English)

    韩其恒; 唐万生; 李光泉

    2003-01-01

    Probability criterion has its practical significance, and its investment decision-making is determined by the expected discounted wealth. In a complete, standard financial market with short-selling allowed, this paper probes into the investment decision-making with probability criterion. The upper limit of criterion function is obtained. The corresponding discounted wealth process and hedging portfolio process are provided. Finally, an illustrative example of one-dimensional constant-coefficient financial market is given.

  3. A Heuristic Criterion for Instability to Fragmentation in Rotating, Interstellar Clouds

    Science.gov (United States)

    Boss, Alan Paul

    1982-01-01

    A heuristic criterion, based on linear perturbation analysis, is applied to the initial growth of density perturbations in isothermal or adiabatic gas clouds, with initially uniform density and uniform rotation. The heuristic criterion is shown to be consistent with the available results from numerical calculations of cloud collapse. The criterion predicts that perturbations varying as cos (m(phi)) will be most likely to grow when )pi is small, unless the cloud is nearly pressureless.

  4. Algebraic-geometric separability criterion and low rank mixed state entanglement

    CERN Document Server

    Chen, H

    2002-01-01

    We first propose a new separability criterion based on algebraic-geometric invariants of bipartite mixed states introduced in [1], then prove that for all low ranks r criterion. This also means that the algebraic-geometric separability criterion proposed here can be used to dectect all low rank entangled mixed states outside a measure zero set.

  5. A simplified approach to directly consider intact rock anisotropy in Hoek–Brown failure criterion

    OpenAIRE

    Mohamed A. Ismael; Hassan F. Imam; Yasser El-Shayeb

    2014-01-01

    Many rock types have naturally occurring inherent anisotropic planes, such as bedding planes, foliation, or flow structures. Such characteristic induces directional features and anisotropy in rocks' strength and deformational properties. The Hoek–Brown (H–B) failure criterion is an empirical strength criterion widely applied to rock mechanics and engineering. A direct modification to H–B failure criterion to account for rock anisotropy is considered as the base of the research. Such modificat...

  6. Couplings in Multi-criterion Aerodynamic Optimization Problems Using Adjoint Methods and Game Strategies

    Institute of Scientific and Technical Information of China (English)

    Tang Zhili; Dong Jun

    2009-01-01

    complete and complete decisions of the leader and followers respectively. Several design examples illustrate the efficiency of the coupling algorithms for multi-criterion aerodynamic design optimization problems.

  7. Slope Safety Factor Calculations With Non-Linear Yield Criterion Using Finite Elements

    DEFF Research Database (Denmark)

    Clausen, Johan; Damkilde, Lars

    2006-01-01

    The factor of safety for a slope is calculated with the finite element method using a non-linear yield criterion of the Hoek-Brown type. The parameters of the Hoek-Brown criterion are found from triaxial test data. Parameters of the linear Mohr-Coulomb criterion are calibrated to the same triaxial...... are carried out at much higher stress levels than present in a slope failure, this leads to the conclusion that the use of the non-linear criterion leads to a safer slope design...

  8. Slope Safety Factor Calculations With Non-Linear Yield Criterion Using Finite Elements

    DEFF Research Database (Denmark)

    Clausen, Johan Christian; Damkilde, Lars

    2006-01-01

    The factor of safety for a slope is calculated with the finite element method using a non-linear yield criterion of the Hoek-Brown type. The parameters of the Hoek-Brown criterion are found from triaxial test data. Parameters of the linear Mohr-Coulomb criterion are calibrated to the same triaxial...... are carried out at much higher stress levels than present in a slope failure, this leads to the conclusion that the use of the non-linear criterion leads to a safer slope design....

  9. Personality types of female transport plane pilots according to Myers-Briggs types indicator%女运输机飞行员迈尔斯布里格斯人格类型分析

    Institute of Scientific and Technical Information of China (English)

    刘红巾; 王扬; 陈静; 苗丹民; 徐先荣; 王建昌

    2013-01-01

    Objective To study the characteristics of personality types of female transport plane pilots according to Myers-Briggs types indicator (MBTI). Methods The personality characteristics of 21 female transport plane pilots were tested following the revised Chinese version of MBTI and compared with those of female officers. Results The scores of extroversion, true feelings, thinking and judgment were higher than those of introversion, intuition, feelings and perception in female transport plane pilots. The personality type of extroversion, true feelings, thinking, judgment was the highest, followed by extroversion, true feelings fellings, judgment;introversion, true feelings, thinking, judgment;extroversion, true feelings, thinking, perception in female transport plane pilots. The scores of extroversion and judgment were higher whereas those of introversion, intuition and perception were lower in female transport plane pilots than in female officers. Conclusion The personality type is characterized by extroversion, true feelings, thinking, judgment in female transport plane pilots according to the MBTI. The personality of female transport plane pilots meeting the MBTI is more suitable to their duty than that of female officers.%目的:探讨女运输机飞行员迈尔斯布里格斯人格类型量表(myers briggs type indicator,MBTI)测量人格类型特征。方法应用修订后的中文版MBTI人格类型量表,对21名女运输机飞行员进行测试并与飞行部队女干部比较。结果女运输机飞行员在外向、实感、思维、判断偏好上的得分均高于内向、直觉、情感、知觉偏好;外向实感思维判断人格类型最多,其次为外向实感情感判断、内向实感思维判断、外向实感思维知觉人格类型。与飞行部队女干部组比较,女飞行员外向、判断得分高而内向、直觉、知觉得分低。结论本组女运输机飞行员MBTI人格类型以外向实感思维判断型为主,与

  10. SALT DAMAGE CRITERION PROOF-OF-CONCEPT RESEARCH

    Energy Technology Data Exchange (ETDEWEB)

    Kerry L. DeVries; Kirby D. Mellegard; Gary D. Callahan

    2001-12-01

    This document is the annual technical progress report for Department of Energy Contract No. DE-FC26-00NT41026 entitled Proof-of-Concept Research for an Advanced Design Criterion to Improve Working Gas Capacity for Natural Gas Storage Caverns in Salt Formations. This report covers the reporting period from October 1, 2000, through September 30, 2001. During this reporting period, the project was initiated and work was performed to develop structural models that will be used to evaluate two compressed natural gas storage caverns in the McIntosh Dome northwest of Mobile, Alabama. Information necessary to define the structural models include site-specific stress, temperature, geometry, stratigraphy, and operating scenarios in the dome and for the caverns. Additionally, material model development for the salt at the McIntosh Dome was initiated. Material model development activities include acquisition of salt core for testing, laboratory testing, and regression analyses to determine site-specific model parameter values that describe the behavior of salt around a storage cavern. Although not performed during this reporting period, the information and models developed will be used to perform advanced design storage cavern analyses for the Bay Gas caverns to determine the operating pressure ranges to maintain stable conditions.

  11. Centration-distortion error: a criterion of perceptual dysfunction.

    Science.gov (United States)

    Mecke, V

    This was a study to determine whether centration, as a perceptual process, could be a criterion for differentiating between neurologically impaired and emotionally disturbed children. Centration was defined by Piaget as a prolonged involuntary attachment of a sensory modality to one part of a field, causing perceptual errors of exaggerations and distortions. It is hypothesized that centration would affect motor behavior, producing effects on drawing tasks characterized by separation of designs or their parts, coincident with distortions of the figures drawn. The neurologically impaired children were identified as having primary difficulties with perception whereas the emotionally disturbed children would have primary difficulties with intellection. The centration-distortion error would characterize the drawing of the neurologically impaired but not those of the emotionally disturbed children. A sample of 44 children was selected, each with EEG records, psychological tests and psychiatric interviews used as differential criteria for the groups. Eleven children were diagnosed as having minimal brain damage, 33 as emotionally disturbed. Three psychologists scored the Bender Gestalt tests, blind, for indicators of brain injury and emotional disturbance as defined by Koppitz' criteria, and for the centration-distortion error. The hypothesis was upheld at the .001 level of confidence, validating an earlier pilot study. PMID:4468761

  12. Fluency: an aim in teaching and a criterion in assessment

    Directory of Open Access Journals (Sweden)

    Aud Marit Simensen

    2010-05-01

    Full Text Available This article investigates the concept ‘fluency’ from different perspectives. When fluency is an aim in teaching, a thorough comprehension of the concept among teachers is a prerequisite for appropriate planning of instruction, including the choice of appropriate classroom activities. When fluency is an assessment criterion, it is even more important that examiners have a shared perception of the concept. The present article starts by presenting common perceptions of the concept and goes on to explore some of the current research. Next, it provides a historical overview of the place of fluency in teaching theory and explains some of the preconditions for the inclusion of this concept among teaching objectives and assessment criteria. It will also, as an illustration, give an outline of the position of the concept over time in the Norwegian school system on the basis of an analysis of the relevant syllabuses. Finally, the article explicates the notion of language use as a complex cognitive skill and explores current method¬ological ideas about teaching towards fluency.

  13. A novel SURE-based criterion for parametric PSF estimation.

    Science.gov (United States)

    Xue, Feng; Blu, Thierry

    2015-02-01

    We propose an unbiased estimate of a filtered version of the mean squared error--the blur-SURE (Stein's unbiased risk estimate)--as a novel criterion for estimating an unknown point spread function (PSF) from the degraded image only. The PSF is obtained by minimizing this new objective functional over a family of Wiener processings. Based on this estimated blur kernel, we then perform nonblind deconvolution using our recently developed algorithm. The SURE-based framework is exemplified with a number of parametric PSF, involving a scaling factor that controls the blur size. A typical example of such parametrization is the Gaussian kernel. The experimental results demonstrate that minimizing the blur-SURE yields highly accurate estimates of the PSF parameters, which also result in a restoration quality that is very similar to the one obtained with the exact PSF, when plugged into our recent multi-Wiener SURE-LET deconvolution algorithm. The highly competitive results obtained outline the great potential of developing more powerful blind deconvolution algorithms based on SURE-like estimates. PMID:25531950

  14. Robust Deep Network with Maximum Correntropy Criterion for Seizure Detection

    Directory of Open Access Journals (Sweden)

    Yu Qi

    2014-01-01

    Full Text Available Effective seizure detection from long-term EEG is highly important for seizure diagnosis. Existing methods usually design the feature and classifier individually, while little work has been done for the simultaneous optimization of the two parts. This work proposes a deep network to jointly learn a feature and a classifier so that they could help each other to make the whole system optimal. To deal with the challenge of the impulsive noises and outliers caused by EMG artifacts in EEG signals, we formulate a robust stacked autoencoder (R-SAE as a part of the network to learn an effective feature. In R-SAE, the maximum correntropy criterion (MCC is proposed to reduce the effect of noise/outliers. Unlike the mean square error (MSE, the output of the new kernel MCC increases more slowly than that of MSE when the input goes away from the center. Thus, the effect of those noises/outliers positioned far away from the center can be suppressed. The proposed method is evaluated on six patients of 33.6 hours of scalp EEG data. Our method achieves a sensitivity of 100% and a specificity of 99%, which is promising for clinical applications.

  15. Robust deep network with maximum correntropy criterion for seizure detection.

    Science.gov (United States)

    Qi, Yu; Wang, Yueming; Zhang, Jianmin; Zhu, Junming; Zheng, Xiaoxiang

    2014-01-01

    Effective seizure detection from long-term EEG is highly important for seizure diagnosis. Existing methods usually design the feature and classifier individually, while little work has been done for the simultaneous optimization of the two parts. This work proposes a deep network to jointly learn a feature and a classifier so that they could help each other to make the whole system optimal. To deal with the challenge of the impulsive noises and outliers caused by EMG artifacts in EEG signals, we formulate a robust stacked autoencoder (R-SAE) as a part of the network to learn an effective feature. In R-SAE, the maximum correntropy criterion (MCC) is proposed to reduce the effect of noise/outliers. Unlike the mean square error (MSE), the output of the new kernel MCC increases more slowly than that of MSE when the input goes away from the center. Thus, the effect of those noises/outliers positioned far away from the center can be suppressed. The proposed method is evaluated on six patients of 33.6 hours of scalp EEG data. Our method achieves a sensitivity of 100% and a specificity of 99%, which is promising for clinical applications. PMID:25105136

  16. A novel SURE-based criterion for parametric PSF estimation.

    Science.gov (United States)

    Xue, Feng; Blu, Thierry

    2015-02-01

    We propose an unbiased estimate of a filtered version of the mean squared error--the blur-SURE (Stein's unbiased risk estimate)--as a novel criterion for estimating an unknown point spread function (PSF) from the degraded image only. The PSF is obtained by minimizing this new objective functional over a family of Wiener processings. Based on this estimated blur kernel, we then perform nonblind deconvolution using our recently developed algorithm. The SURE-based framework is exemplified with a number of parametric PSF, involving a scaling factor that controls the blur size. A typical example of such parametrization is the Gaussian kernel. The experimental results demonstrate that minimizing the blur-SURE yields highly accurate estimates of the PSF parameters, which also result in a restoration quality that is very similar to the one obtained with the exact PSF, when plugged into our recent multi-Wiener SURE-LET deconvolution algorithm. The highly competitive results obtained outline the great potential of developing more powerful blind deconvolution algorithms based on SURE-like estimates.

  17. Peru; First Review Under the Stand-By Arrangement and Requests for Modification of Performance Criterion and Waiver for Nonobservance of Performance Criterion

    OpenAIRE

    International Monetary Fund

    2007-01-01

    The staff report for the First Review Under the Stand-By Arrangement and Requests for Waiver of Performance Criterion and Waiver for Nonobservance of Performance Criterion highlights Peru’s policy discussions and staff appraisal. A draft law was prepared with a view to establishing sanctions for noncompliance with the law’s fiscal deficit target. Monetary policy continues to be managed prudently within the inflation-targeting framework. The central bank expects dollarization to gradually ...

  18. BOUNDEDNESS CRITERION FOR SOME COMMUTATORS OF LINEAR OPERATORS

    Institute of Scientific and Technical Information of China (English)

    Chen Wengu; Hu Guoen

    2001-01-01

    The paper is to establish a boundedness criterion for somecommutators of linear operators when these linear operators don't satisfy the general Ap weight estimates but satisfy some radial weight estimates. CLC Number:O17 Document ID:AFoundation Item:The paper was partly supported by National Natural Science Foundation of China (No. 19901021) and Beijing Education Commission Foundation, Natural Science Foundation of Beijing (1013006). References:[1]Coifman,R. and Meyer,Y. ,Au déla Des Opérateurs Pseudo-Différentiles,Astérisque 57(1978),1-185.[2]Alvarez,J. ,Bagby,R. ,Kurtz,D. and Pérez,C. ,Weighted Estimates for Commutators of Linear Operators,Studia Math. 104 (1993),195-[2]09.[3]Hu G. and Lu S. Z. ,The Commutator of the Bochner-Riesz Operator,Tohoku Math. J. 48(1996) ,259-266.[4]Duoandikoetxea,J. ,Weighted Norm Inequalities for Homogeneous Singular Integrals,Trans.Amer,Math. Soc.[3]36(1993),869-880.[5]Stein,E. M. and Weiss,G. ,Interpolation of Operators with Change of Measures,Trans.Amer. Math. Soc. 87(1958),159-172.[6]Zaanea,A. C. ,Interpolation,North-Holland,1967.[7]Ding Y. and Lu S. Z. ,Weighted Lp-Bounedness for Higher Order Commutators of Oscillatory Singular Integrals,Tohoku Math. J. 48(1996),437-449.Manuscript Received:1999年12月22日Published:2001年9月1日

  19. Criterion-based (proficiency) training to improve surgical performance.

    Science.gov (United States)

    Fried, Marvin P; Kaye, Rachel J; Gibber, Marc J; Jackman, Alexis H; Paskhover, Boris P; Sadoughi, Babak; Schiff, Bradley; Fraioli, Rebecca E; Jacobs, Joseph B

    2012-11-01

    OBJECTIVE To investigate whether training otorhinolaryngology residents to criterion performance levels (proficiency) on the Endoscopic Sinus Surgery Simulator produces individuals whose performance in the operating room is at least equal to those who are trained by performing a fixed number of surgical procedures. DESIGN Prospective cohort. SETTING Two academic medical centers in New York City. PARTICIPANTS Otorhinolaryngology junior residents composed of 8 experimental subjects and 6 control subjects and 6 attending surgeons. INTERVENTION Experimental subjects achieved benchmark proficiency criteria on the Endoscopic Sinus Surgery Simulator; control subjects repeated the surgical procedure twice. MAIN OUTCOME MEASURES Residents completed validated objective tests to assess baseline abilities. All subjects were videotaped performing an initial standardized surgical procedure. Residents were videotaped performing a final surgery. Videotapes were assessed for metrics by an expert panel. RESULTS Attendings outperformed the residents in most parameters on the initial procedure. Experimental and attending groups outperformed controls in some parameters on the final procedure. There was no difference between resident groups in initial performance, but the experimental subjects outperformed the control subjects in navigation in the final procedure. Most important, there was no difference in final performance between subgroups of the experimental group on the basis of the number of trials needed to attain proficiency. CONCLUSIONS Simulator training can improve resident technical skills so that each individual attains a proficiency level, despite the existence of an intrinsic range of abilities. This proficiency level translates to at least equal, if not superior, operative performance compared with that of current conventional training with finite repetition of live surgical procedures.

  20. Interpretation to Restraint Standards of Joanna Briggs Institute%澳大利亚循证卫生保健中心身体约束标准介绍

    Institute of Scientific and Technical Information of China (English)

    成守珍; 高明榕; 王若婧

    2014-01-01

    The authors summarized the Restraint Standards of Joanna Briggs Institute, and introduced the deifnition of physical restraint, the responsibilities of nurses, the principles and management of implementing physical restraint, the reason of physical restraint, measures to reduce physical restraint, and patient management of aged patients, to provide references for physical restraint in our country.%本文对2013年7月澳大利亚循证卫生保健中心(JBI)在其网站公布的身体约束标准中对身体约束的定义、护士的责任、实施身体约束的原则及管理、身体约束的原因、减少身体约束的措施及对老年人的约束7个方面进行了介绍,以期为我国身体约束的使用提供参考。

  1. Criterion-Referenced and Norm-Referenced Assessments: Compatibility and Complementarity

    Science.gov (United States)

    Lok, Beatrice; McNaught, Carmel; Young, Kenneth

    2016-01-01

    The tension between criterion-referenced and norm-referenced assessment is examined in the context of curriculum planning and assessment in outcomes-based approaches to higher education. This paper argues the importance of a criterion-referenced assessment approach once an outcomes-based approach has been adopted. It further discusses the…

  2. 76 FR 33740 - Final Priorities and Selection Criterion; National Institute on Disability and Rehabilitation...

    Science.gov (United States)

    2011-06-09

    ... Final Priorities and Selection Criterion; National Institute on Disability and Rehabilitation Research... criterion for Disability and Rehabilitation Research Projects (DRRPs) that will serve as the SCIMS Multi... telecommunications device for the deaf (TDD), call the Federal Relay Service, toll free, at...

  3. Energy-efficient induction motors designing with application of a modified criterion of reduced costs

    Directory of Open Access Journals (Sweden)

    V.S. Petrushin

    2014-03-01

    Full Text Available The paper introduces a modified criterion of reduced costs that employs coefficients of operation significance and priority of ohmic loss accounting to allow matching maximum efficiency with minimum reduced costs. Impact of the inflation factor on the criterion of reduced costs is analyzed.

  4. A blow-up criterion for classical solutions to the compressible Navier-Stokes equations

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In this paper, we obtain a blow-up criterion for classical solutions to the 3-D compressible Navier-Stokes equations just in terms of the gradient of the velocity, analogous to the Beal-Kato-Majda criterion for the ideal incompressible flow. In addition, the initial vacuum is allowed in our case.

  5. On a criterion of similarity of the plasma accelerators of the stationary plasma jet engine type

    International Nuclear Information System (INIS)

    One examined operation of ATON stationary plasma jet engine with various working gases. Applying criterion of similarity one selected the optimal operation of engine using krypton. Paper presents comparison integral parameters of engine operated by krypton and xenon. It is shown that when using various working media engine operates under similar modes at similar values of similarity criterion

  6. A new risk-based screening criterion for treatment-demanding retinopathy of prematurity in Denmark

    DEFF Research Database (Denmark)

    Slidsborg, Carina; Forman, Julie Lyng; Rasmussen, Steen Christian;

    2011-01-01

    The aim of this study was to uncover the most effective and safe criterion to implement for retinopathy of prematurity screening in Denmark.......The aim of this study was to uncover the most effective and safe criterion to implement for retinopathy of prematurity screening in Denmark....

  7. Evaluation of Regression Models of Balance Calibration Data Using an Empirical Criterion

    Science.gov (United States)

    Ulbrich, Norbert; Volden, Thomas R.

    2012-01-01

    An empirical criterion for assessing the significance of individual terms of regression models of wind tunnel strain gage balance outputs is evaluated. The criterion is based on the percent contribution of a regression model term. It considers a term to be significant if its percent contribution exceeds the empirical threshold of 0.05%. The criterion has the advantage that it can easily be computed using the regression coefficients of the gage outputs and the load capacities of the balance. First, a definition of the empirical criterion is provided. Then, it is compared with an alternate statistical criterion that is widely used in regression analysis. Finally, calibration data sets from a variety of balances are used to illustrate the connection between the empirical and the statistical criterion. A review of these results indicated that the empirical criterion seems to be suitable for a crude assessment of the significance of a regression model term as the boundary between a significant and an insignificant term cannot be defined very well. Therefore, regression model term reduction should only be performed by using the more universally applicable statistical criterion.

  8. A Controlled Evaluation of the Distress Criterion for Binge Eating Disorder

    Science.gov (United States)

    Grilo, Carlos M.; White, Marney A.

    2011-01-01

    Objective: Research has examined various aspects of the validity of the research criteria for binge eating disorder (BED) but has yet to evaluate the utility of Criterion C, "marked distress about binge eating." This study examined the significance of the marked distress criterion for BED using 2 complementary comparison groups. Method: A total of…

  9. A criterion-related validity study of the nursing-care dependency (NCD) scale

    NARCIS (Netherlands)

    Dijkstra, A.; Buist, G.; Dassen, Th.W.N.

    1998-01-01

    The purpose of this study was to examine some aspects of the criterion-related validity of the Nursing-Care Dependency (NCD) scale. This 15-item counting scale has recently been developed for assessing the care dependency of demented or mentally handicapped in-patients. Its criterion-related validit

  10. Working Memory in Children with Learning Disabilities: Rethinking the Criterion of Discrepancy

    Science.gov (United States)

    Maehler, Claudia; Schuchardt, Kirsten

    2011-01-01

    The criterion of discrepancy is used to distinguish children with learning disorders from children with intellectual disabilities. The justification of the criterion of discrepancy for the diagnosis of learning disorders relies on the conviction of fundamental differences between children with learning difficulties with versus without discrepancy…

  11. A Controlled Evaluation of the Distress Criterion for Binge Eating Disordspan>er

    Science.gov (United States)

    Grilo, Carlos M.; White, Marney A.

    2011-01-01

    Objective: Research has examined various aspects of the validity of the research criteria for binge eating disorder (BED) but has yet to evaluate the utility of Criterion C, "marked distress about binge eating." This study examined the significance of the marked distress criterion for BED using 2 complementary comparison groups. Method: A total of…

  12. Energy-efficient induction motors designing with application of a modified criterion of reduced costs

    OpenAIRE

    V.S. Petrushin

    2014-01-01

    The paper introduces a modified criterion of reduced costs that employs coefficients of operation significance and priority of ohmic loss accounting to allow matching maximum efficiency with minimum reduced costs. Impact of the inflation factor on the criterion of reduced costs is analyzed.

  13. Maximum twin shear stress factor criterion for sliding mode fracture initiation

    Institute of Scientific and Technical Information of China (English)

    黎振兹; 李慧剑; 黎晓峰; 周洪彬; 郝圣旺

    2002-01-01

    Previous researches on the mixed mode fracture initiation criteria were mostly focused on opening mode fracture. In this study, the authors proposed a new criterion for mixed mode sliding fracture initiation, which is the maximum twin shear stress factor criterion. The authors studied a finite width plate with central slant crack, subject to a far-field uniform uniaxial tensile or compressive stress.

  14. Chirikov criterion of resonance overlapping for the model of molecular dynamics

    CERN Document Server

    Guzev, M A

    2012-01-01

    The chaotic dynamics in a cell of particles' chain interacting by means of Lennard-Jones potential is considered. Chirikov criterion of resonance over- lapping is used as the condition of chaos. The asymptotic representation for this function at low and high energies is obtained for the function corresponding to the criterion.

  15. Does the Lowest Bid Price Evaluation Criterion Make for a More Efficient Public Procurement Selection Criterion? (Case of the Czech Republic

    Directory of Open Access Journals (Sweden)

    Ochrana František

    2015-06-01

    Full Text Available Through the institute of public procurement a considerable volume of financial resources is allocated. It is therefore in the interest of contracting entities to seek ways of how to achieve an efficient allocation of resources. Some public contract-awarding entities, along with some public-administration authorities in the Czech Republic, believe that the use of a single evaluation criterion (the lowest bid price results in a more efficient tender for a public contract. It was found that contracting entities in the Czech Republic strongly prefer to use the lowest bid price criterion. Within the examined sample, 86.5 % of public procurements were evaluated this way. The analysis of the examined sample of public contracts proved that the choice of an evaluation criterion, even the preference of the lowest bid price criterion, does not have any obvious impact on the final cost of a public contract. The study concludes that it is inappropriate to prefer the criterion of the lowest bid price within the evaluation of public contracts that are characterised by their complexity (including public contracts for construction works and public service contracts. The findings of the Supreme Audit Office related to the inspection of public contracts indicate that when using the lowest bid price as an evaluation criterion, a public contract may indeed be tendered with the lowest bid price, but not necessarily the best offer in terms of supplied quality. It is therefore not appropriate to use the lowest bid price evaluation criterion to such an extent for the purpose of evaluating work and services. Any improvement to this situation requires a corresponding amendment to the Law on Public Contracts and mainly a radical change in the attitude of the Office for the Protection of Competition towards proposed changes, as indicated within the conclusions and recommendations proposed by this study.

  16. A computed tomography reconstruction algorithm based on multipurpose optimal criterion and simulated annealing theory

    Institute of Scientific and Technical Information of China (English)

    Hui Li; Xiong Wan; Taoli Liu; Zhongshou Liu; Yanhua Zhu

    2007-01-01

    Although emission spectral tomography (EST) combines emission spectral measurement with optical computed tomography (OCT), it is difficult to gain transient emission data from a large number of views,therefore, high precision OCT algorithms with few views ought to be studied for EST application. To improve the reconstruction precision in the case of few views, a new computed tomography reconstruction algorithm based on multipurpose optimal criterion and simulated annealing theory (multi-criterion simulated annealing reconstruction technique, MCSART) is proposed. This algorithm can suffice criterion of least squares, criterion of most uniformity, and criterion of most smoothness synchronously. We can get global optimal solution by MCSART algorithm with simulated annealing theory. The simulating experiment result shows that this algorithm is superior to the traditional algorithms under various noises.

  17. An Integrated Pruning Criterion for Ensemble Learning Based on Classification Accuracy and Diversity

    DEFF Research Database (Denmark)

    Fu, Bin; Wang, Zhihai; Pan, Rong;

    2013-01-01

    Ensemble pruning is an important issue in the field of ensemble learning. Diversity is a key criterion to determine how the pruning process has been done and measure what result has been derived. However, there is few formal definitions of diversity yet. Hence, three important factors that should...... be further considered while designing a pruning criterion is presented, and then an effective definition of diversity is proposed. The experimental results have validated that the given pruning criterion could single out the subset of classifiers that show better performance in the process of hill......-climbing search, compared with other definitions of diversity and other criteria....

  18. 仿人机器人跑步稳定性准则%Stability Criterion for Humanoid Running

    Institute of Scientific and Technical Information of China (English)

    李朝晖; 黄强; 李科杰

    2005-01-01

    A humanoid robot has high mobility but possibly risks of tipping over. Until now, one main topic on humanoid robots is to study the walking stability; the issue of the running stability has rarely been investigated. The running is different from the walking, and is more difficult to maintain its dynamic stability. The objective of this paper is to study the stability criterion for humanoid running based on the whole dynamics. First, the cycle and the dynamics of running are analyzed. Then, the stability criterion of humanoid running is presented. Finally, the effectiveness of the proposed stability criterion is illustrated by a dynamic simulation example using a dynamic analysis and design system (DADS).

  19. A new variant selection criterion for twin variants in titanium alloys. Pt. 2

    Energy Technology Data Exchange (ETDEWEB)

    Schuman, Christophe [Laboratoire d' Etude des Microstructures et de Mecanique des Materiaux, LEM3, CNRS 7239, Universite Paul Verlaine - Metz, Ile du Saulcy, Metz (France); Bao, Lei; Lecomte, Jean Sebastien; Zhang, Yudong; Raulot, Jean Marc; Philippe, Marie Jeanne; Esling, Claude [LEM3, CNRS 7239, Universite Paul Verlaine - Metz, Ile du Saulcy, Metz (France)

    2012-05-15

    A new selection criterion to explain the activation of the twinning variant is proposed. This criterion is based on the calculation of the deformation energy to create a primary twin. The calculation takes into account the effect of the grain size using a Hall-Petch type relation. This criterion allows to obtain a very good prediction for the twin family selection and twin variant selection. The calculations are compared with the experimental results obtained on T40 (ASTM grade 2) deformed by Channel Die compression. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  20. Novel frequency-domain criterion for elimination of limit cycles in a class of digital filters with single saturation nonlinearity

    International Nuclear Information System (INIS)

    A frequency-domain criterion for the elimination of limit cycles in a class of digital filters utilizing single saturation nonlinearity is presented. The criterion is derived by exploiting the structural properties of the system under consideration in a greater detail. A novel feature of the criterion is that it takes the form of a matrix inequality, despite the fact that there is single nonlinearity in the system. An example showing the effectiveness of the criterion is given

  1. A Criterion for Determining the Number of Clusters%确定聚类数目的一个准则

    Institute of Scientific and Technical Information of China (English)

    郝立丽; 郝立柱

    2008-01-01

    Aiming to provide an appropriate number K of clusters, in this paper, we propose a new criterion function -- H criterion function, whose three properties have also been proved. We validate the performance of the H criterion function on one artificial dataset and three real-world datasets, and the results are almostly consistent with a previous method. The nonparametric criterion we proposed is intuitive, simple and the computational cost is acceptable.

  2. BLOW-UP CRITERION OF SMOOTH SOLUTIONS TO THE MHD EQUATIONS IN BESOV SPACES

    Institute of Scientific and Technical Information of China (English)

    YUAN Baoquan

    2005-01-01

    In this paper we discuss the logarithmic Sobolev inequalities in Besov spaces,and show their applications to the blow-up criterion of smooth solutions to the incompressible magneto-hydrodynamics equations.

  3. Analysis of a delayed fracture criterion for lifetime prediction of viscoelastic polymer materials

    Science.gov (United States)

    Guedes, Rui Miranda

    2012-08-01

    In this work a multi-axial yield/failure model for viscoelastic/plastic materials is applied, which was developed by Naghdi and Murch (in J. Appl. Mech. 30:321-328, 1963) and later extended and refined by Crochet (in J. Appl. Mech. 33:327-334, 1966), to predict long-term creep rupture of polymers. The criterion defines a function, which depends on time, the viscoelastic properties and applied stress, to establish an empirical law with creep yield (fracture). In this work a linear relationship is proposed, defined as a time-dependent failure criterion, which can be applied for extrapolation purposes. A comparative analysis using energy-based failure criteria is performed. It is proved, for the polymers considered in this study, that the proposed time-dependent failure criterion holds for long times. Experimental data are used to illustrate the applicability of this time-dependent failure criterion.

  4. TEMPERATURE-DEFORMATION CRITERION OF OPTIMIZATION OF FINE DRAWING HIGH CARBON WIRE ROUTE

    Directory of Open Access Journals (Sweden)

    Y. L. Bobarikin

    2012-01-01

    Full Text Available The temperature-deformation criterion of assessment and optimization of routes of the thin high-carbon wire drawing enabling to increase plastic properties of wire at retaining of its durability is offered.

  5. A regularity criterion for the angular velocity component in axisymmetric Navier-Stokes equations

    OpenAIRE

    Ondrej Kreml; Milan Pokorny

    2007-01-01

    We study the non-stationary Navier-Stokes equations in the entire three-dimensional space under the assumption that the data are axisymmetric. We extend the regularity criterion for axisymmetric weak solutions given in [10].

  6. A regularity criterion for the angular velocity component in axisymmetric Navier-Stokes equations

    Directory of Open Access Journals (Sweden)

    Ondrej Kreml

    2007-01-01

    Full Text Available We study the non-stationary Navier-Stokes equations in the entire three-dimensional space under the assumption that the data are axisymmetric. We extend the regularity criterion for axisymmetric weak solutions given in [10].

  7. On the regularity criterion of weak solution for the 3D viscous Magneto-hydrodynamics equations

    OpenAIRE

    Chen, Qionglei; Miao, Changxing; Zhang, Zhifei

    2007-01-01

    We improve and extend some known regularity criterion of weak solution for the 3D viscous Magneto-hydrodynamics equations by means of the Fourier localization technique and Bony's para-product decomposition.

  8. Improved similarity criterion for seepage erosion using mesoscopic coupled PFC-CFD model

    Institute of Scientific and Technical Information of China (English)

    倪小东; 王媛; 陈珂; 赵帅龙

    2015-01-01

    Conventional model tests and centrifuge tests are frequently used to investigate seepage erosion. However, the centrifugal test method may not be efficient according to the results of hydraulic conductivity tests and piping erosion tests. The reason why seepage deformation in model tests may deviate from similarity was first discussed in this work. Then, the similarity criterion for seepage deformation in porous media was improved based on the extended Darcy-Brinkman-Forchheimer equation. Finally, the coupled particle flow code–computational fluid dynamics (PFC−CFD) model at the mesoscopic level was proposed to verify the derived similarity criterion. The proposed model maximizes its potential to simulate seepage erosion via the discrete element method and satisfy the similarity criterion by adjusting particle size. The numerical simulations achieved identical results with the prototype, thus indicating that the PFC−CFD model that satisfies the improved similarity criterion can accurately reproduce the processes of seepage erosion at the mesoscopic level.

  9. A criterion for high-cycle fatigue life and fatigue limit prediction in biaxial loading conditions

    Science.gov (United States)

    Pejkowski, Łukasz; Skibicki, Dariusz

    2016-08-01

    This paper presents a criterion for high-cycle fatigue life and fatigue strength estimation under periodic proportional and non-proportional cyclic loading. The criterion is based on the mean and maximum values of the second invariant of the stress deviator. Important elements of the criterion are: function of the non-proportionality of fatigue loading and the materials parameter that expresses the materials sensitivity to non-proportional loading. The methods for the materials parameters determination uses three S-N curves: tension-compression, torsion, and any non-proportional loading proposed. The criterion has been verified using experimental data, and the results are included in the paper. These results should be considered as promising. The paper also includes a proposal for multiaxial fatigue models classification due to the approach for the non-proportionality of loading.

  10. STRENGTH CRITERION FOR PLAIN CONCRETE UNDER MULTIAXIAL STRESS BASED ON DAMAGE POISSON'S RATIO

    Institute of Scientific and Technical Information of China (English)

    Ding Faxing; Yu Zhiwu

    2006-01-01

    A new unified strength criterion in the principal stress space has been proposed for use with normal strength concrete (NC) and high strength concrete (HSC) in compressioncompression-tension, compression-tension-tension, triaxial tension, and biaxial stress states. The study covers concrete with strengths ranging from 20 to 130 Mpa. The conception of damage Poisson's ratio is defined and the expression for damage Poisson's ratio is determined basically.The failure mechanism of concrete is illustrated, which points out that damage Poisson's ratio is the key to determining the failure of concrete. Furthermore, for the concrete under biaxial stress conditions, the unified strength criterion is simplified and a simplified strength criterion in the form of curves is also proposed. The strength criterion is physically meaningful and easy to calculate, which can be applied to analytic solution and numerical solution of concrete structures.

  11. Criterion for the onset of quench for low-flow reflood

    International Nuclear Information System (INIS)

    This study provides a criterion for the onset of quench for low flow reflood. The criterion is a combination of two conditions: T/sub clad/ < T/sub limiting quench/ where T = Temperature, and α < 0.95 where α = void fraction. This criterion was obtained by examining temperature data from tests simulating PWR reflood, such as FLECHT, THTF, PBF, CCTF, and FEBA tests, with void fraction data from CCTF, FEBA, and FLECHT low flood tests. The data show that quenching initiated at α = 0.95 and that the majority of quench occurred at void fractions near 0.85. The results show that rods can be completely quenched by entrained droplets even if the collapsed liquid level does not advance. A thorough discussion of the analysis which supports this quench criterion is given in the text of this report

  12. A coupled elastoplastic-damage constitutive model with Lode angle dependent failure criterion

    OpenAIRE

    Erice Echávarri, Borja; Galvez Diaz-Rubio, Francisco

    2014-01-01

    A coupled elastoplastic-damage constitutive model with Lode angle dependent failure criterion for high strain and ballistic applications is presented. A Lode angle dependent function is added to the equivalent plastic strain to failure definition of the Johnson–Cook failure criterion. The weakening in the elastic law and in the Johnson–Cook-like constitutive relation implicitly introduces the Lode angle dependency in the elastoplastic behaviour. The material model is calibrated for precipitat...

  13. Seismic bearing capacity of strip footings on rock masses using the Hoek–Brown failure criterion

    OpenAIRE

    Amin Keshavarz; Abdoreza Fazeli; Siavosh Sadeghi

    2016-01-01

    In this paper, the bearing capacity of strip footings on rock masses has been studied in the seismic case. The stress characteristics or slip line method was used for analysis. The problem was analyzed in the plane strain condition using the Hoek–Brown failure criterion. First, the equilibrium equations along the stress characteristics were obtained and the rock failure criterion was applied. Then, the equations were solved using the finite difference method. A computer code has been provided...

  14. Monitoring of Education Environment according to the Social-Psychological Safety Criterion

    OpenAIRE

    Pavel Aleksandrovich Kislyakov; Elena Aleksandrovna Shmeleva; Tat'yana Vyacheslavovna Karaseva; Ol'ga Aleksandrovna Silaeva

    2014-01-01

    The aim of this work is to reveal psychological indices for the monitoring of education environment according to the students' social-psychological safety criterion and to specify their interrelation. The article presents theoretical and methodological bases of the monitoring of students' social-psychological safety criterion in a higher educational establishment. The article presents the review of approaches to the definition of key features of education environment including psychosocial we...

  15. Implicit optimality criterion for convex SIP problem with box constrained index set

    OpenAIRE

    Kostyukova, O. I.; Tchemisova, T. V.

    2012-01-01

    We consider a convex problem of Semi-Infinite Programming (SIP) with multidimensional index set. In study of this problem we apply the approach suggested in [20] for convex SIP problems with one-dimensional index sets and based on the notions of immobile indices and their immobility orders. For the problem under consideration we formulate optimality conditions that are explicit and have the form of criterion. We compare this criterion with other known optimality conditions for ...

  16. A Criterion for Stability of Synchronization and Application to Coupled Chua's Systems

    Institute of Scientific and Technical Information of China (English)

    WANG Hai-Xia; LU Qi-Shao; WANG Qing-Yun

    2009-01-01

    We investigate synchronization in an array network of nearest-neighbor coupled chaotic oscillators. By using of the Lyapunov stability theory and matrix theory, a criterion for stability of complete synchronization is deduced. Meanwhile, an estimate of the critical coupling strength is obtained to ensure achieving chaos synchronization. As an example application, a model of coupled Chua's circuits with linearly bidirectional coupling is studied to verify the validity of the criterion.

  17. A novel stability criterion for interval time-delay chaotic systems via the evolutionary programming approach

    Energy Technology Data Exchange (ETDEWEB)

    Yan, J.-J. [Department of Computer and Communication, Shu-Te University, Kaohsiung 824, Taiwan (China)]. E-mail: jjyan@mail.stu.edu.tw; Hung, M.-L. [Department of Electrical Engineering, Far-East College, No. 49, Jung-Haw Road, Hsin-Shih Town, Tainan 744, Taiwan (China)

    2006-09-15

    This paper investigates a novel stability criterion for interval time-delay chaotic systems via the evolutionary programming (EP) approach. First a delay-dependent criterion is derived for ensuring the stability of degenerate time-delay systems, and then by solving eigenvalue location optimization problems, which will be defined later, the robust stability of interval time-delay systems can be guaranteed. An example is given to verify our method that yields less conservative results than those appeared in the literature.

  18. Exo-planet detection with the COROT space mission. I. A multi-transit detection criterion

    CERN Document Server

    Bordé, P J; Léger, A; Borde', Pascal; Rouan, Daniel; Leger, Alain

    2001-01-01

    We present a detection criterion for exo-planets to be used with the space mission COROT. This criterion is based on the transit method, which suggests the observation of star dimming caused by partial occulations by planetary companions. When at least three transits are observed, we show that a cross-correlation technique can yield a detection threshold, thus enabling the evaluation of the number of possible detections, assuming a model for the stellar population in the Galaxy.

  19. Covariance-Based Measurement Selection Criterion for Gaussian-Based Algorithms

    OpenAIRE

    Auat Cheein, Fernando A.

    2013-01-01

    Process modeling by means of Gaussian-based algorithms often suffers from redundant information which usually increases the estimation computational complexity without significantly improving the estimation performance. In this article, a non-arbitrary measurement selection criterion for Gaussian-based algorithms is proposed. The measurement selection criterion is based on the determination of the most significant measurement from both an estimation convergence perspective and the covariance ...

  20. The Effect of Vitamin C Vaginal Tablets on Amsel Criterion in Patients with Bacterial Vaginosis

    OpenAIRE

    F Godarzi; Z Abaspour; MR Abaspour; E Moomeni; KA Zandi

    2011-01-01

    Background & aim: Bacterial vaginosis is the common cause of vaginitis among women of reproductive ages. Amsel criterion is the most accurate and applicable diagnosis method for bacterial vaginosis. The aim of the present study was to evaluate the effect of vitamin C vaginal tablets on the Amsel criterion. Methods: After confirmed diagnosis of bacterial vaginosis to Amsel criteria (having at least 3 out of the 4 characteristic symptoms including discharge, fishy odor, vaginal pH≥4.5, and...

  1. A novel delay-dependent criterion for delayed neural networks of neutral type

    Science.gov (United States)

    Lee, S. M.; Kwon, O. M.; Park, Ju H.

    2010-04-01

    This Letter considers a robust stability analysis method for delayed neural networks of neutral type. By constructing a new Lyapunov functional, a novel delay-dependent criterion for the stability is derived in terms of LMIs (linear matrix inequalities). A less conservative stability criterion is derived by using nonlinear properties of the activation function of the neural networks. Two numerical examples are illustrated to show the effectiveness of the proposed method.

  2. A novel delay-dependent criterion for delayed neural networks of neutral type

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S.M., E-mail: moony@daegu.ac.k [Department of Electronic Engineering, Daegu University, Gyungsan 712-714 (Korea, Republic of); Kwon, O.M., E-mail: madwind@chungbuk.ac.k [School of Electrical Engineering, Chungbuk National University, 410 SungBong-Ro, Heungduk-gu, Cheongju 361-763 (Korea, Republic of); Park, Ju H., E-mail: jessie@ynu.ac.k [Department of Electrical Engineering, Yeungnam University, 214-1 Dae-Dong, Kyongsan 712-749 (Korea, Republic of)

    2010-04-12

    This Letter considers a robust stability analysis method for delayed neural networks of neutral type. By constructing a new Lyapunov functional, a novel delay-dependent criterion for the stability is derived in terms of LMIs (linear matrix inequalities). A less conservative stability criterion is derived by using nonlinear properties of the activation function of the neural networks. Two numerical examples are illustrated to show the effectiveness of the proposed method.

  3. Stochastic estimation of the Frobenius norm in the ACA convergence criterion

    OpenAIRE

    Heldring, Alexander; Úbeda Farré, Eduard; Rius Casals, Juan Manuel

    2015-01-01

    The adaptive cross approximation (ACA) algorithm has been used in many fast Integral Equation solvers for electromagnetic Radiation and Scattering problems. It efficiently computes a low rank approximation to the interaction matrix between mutually distant parts of a scattering object. The ACA is an iterative algorithm that needs an accurate and efficient convergence criterion. The evaluation of this criterion may consume a considerable part of the computational resources. This communication ...

  4. LSSVM-Based Rock Failure Criterion and Its Application in Numerical Simulation

    OpenAIRE

    Changxing Zhu; Hongbo Zhao; Zhongliang Ru

    2015-01-01

    A rock failure criterion is very important for the prediction of the failure of rocks or rock masses in rock mechanics and engineering. Least squares support vector machines (LSSVM) are a powerful tool for addressing complex nonlinear problems. This paper describes a LSSVM-based rock failure criterion for analyzing the deformation of a circular tunnel under different in situ stresses without assuming a function form. First, LSSVM was used to represent the nonlinear relationship between the me...

  5. An existential criterion for normal and abnormal personality in the works of Erich Fromm

    OpenAIRE

    KAPUSTIN SERGEY A.

    2015-01-01

    This is the first of four articles scheduled for publication in this journal on the position people with normal and abnormal personalities take in regard to so-called existential dichotomies. The main objective of this article is to propose a new, existential criterion for normal and abnormal personality implicitly present in the works of Erich Fromm. According to this criterion, normal and abnormal personalities are determined, first, by special features of the content of their position rega...

  6. A new criterion to determine the start of combustion in diesel engines

    OpenAIRE

    Rodman Oprešnik, Samuel; Trenc, Ferdinand; Katrašnik, Tomaž

    2015-01-01

    A new criterion for the determination of the start of combustion (SOC) from the diesel engine in-cylinder pressure diagram was developed. It is defined asthe maximum of the third-order derivative of the cylinder pressure with respect to the crank angle. This criterion declares SOC more precisely than other previously published criteria based on pressure diagnostics. This fact was proven analytically and was discernable from the analysis of the experimental data. Besides its accuracy it is als...

  7. Multiaxial fatigue criterion based on parameters from torsion and axial S-N curve

    Directory of Open Access Journals (Sweden)

    M. Margetin

    2016-07-01

    Full Text Available Multiaxial high cycle fatigue is a topic that concerns nearly all industrial domains. In recent years, a great deal of recommendations how to address problems with multiaxial fatigue life time estimation have been made and a huge progress in the field has been achieved. Until now, however, no universal criterion for multiaxial fatigue has been proposed. Addressing this situation, this paper offers a design of a new multiaxial criterion for high cycle fatigue. This criterion is based on critical plane search. Damage parameter consists of a combination of normal and shear stresses on a critical plane (which is a plane with maximal shear stress amplitude. Material parameters used in proposed criterion are obtained from torsion and axial S-N curves. Proposed criterion correctly calculates life time for boundary loading condition (pure torsion and pure axial loading. Application of proposed model is demonstrated on biaxial loading and the results are verified with testing program using specimens made from S355 steel. Fatigue material parameters for proposed criterion and multiple sets of data for different combination of axial and torsional loading have been obtained during the experiment.

  8. Failure Study of Composite Materials by the Yeh-Stratton Criterion

    Science.gov (United States)

    Yeh, Hsien-Yang; Richards, W. Lance

    1997-01-01

    The newly developed Yeh-Stratton (Y-S) Strength Criterion was used to study the failure of composite materials with central holes and normal cracks. To evaluate the interaction parameters for the Y-S failure theory, it is necessary to perform several biaxial loading tests. However, it is indisputable that the inhomogeneous and anisotropic nature of composite materials have made their own contribution to the complication of the biaxial testing problem. To avoid the difficulties of performing many biaxial tests and still consider the effects of the interaction term in the Y-S Criterion, a simple modification of the Y-S Criterion was developed. The preliminary predictions by the modified Y-S Criterion were relatively conservative compared to the testing data. Thus, the modified Y-S Criterion could be used as a design tool. To further understand the composite failure problem, an investigation of the damage zone in front of the crack tip coupled with the Y-S Criterion is imperative.

  9. A Criterion for Brittle Failure of Rocks Using the Theory of Critical Distances

    Science.gov (United States)

    Castro, Jorge; Cicero, Sergio; Sagaseta, César

    2016-01-01

    This paper presents a new analytical criterion for brittle failure of rocks and heavily over-consolidated soils. Griffith's model of a randomly oriented defect under a biaxial stress state is used to keep the criterion simple. The Griffith's criterion is improved because the maximum tensile strength is not evaluated at the boundary of the defect but at a certain distance from the boundary, known as half of the critical distance. This fracture criterion is known as the point method, and is part of the theory of critical distances, which is utilised in fracture mechanics. The proposed failure criterion has two parameters: the inherent tensile strength, σ 0, and the ratio of the half-length of the initial crack/flaw to the critical distance, a/ L. These parameters are difficult to measure but they may be correlated with the uniaxial compressive and tensile strengths, σ c and σ t. The proposed criterion is able to reproduce the common range of strength ratios for rocks and heavily overconsolidated soils ( σ c/ σ t = 3-50) and the influence of several microstructural rock properties, such as texture and porosity. Good agreement with laboratory tests reported in the literature is found for tensile and low-confining stresses.

  10. A new criterion for the allocation of residues cost in exergoeconomic analysis of energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Seyyedi, Seyyed Masoud; Ajam, Hossein; Farahat, Said [Department of Mechanical Engineering, University of Sistan and Baluchestan, Zahedan 98164 (Iran)

    2010-08-15

    In any energy system that produces work, heat and so on, disposal remaining flows of matter or energy, which are called residues, will appear. In the exergoeconomic analysis of these systems, one of the complex problems is residues cost allocation in a rational way. Two more important criteria of the residues cost allocation are distribution of the cost of the residues proportional to the exergy as well as proportional to the entropy generation or negentropy. In this paper, a new criterion for the residues cost allocation is proposed that it is based on the entropy distributed in the components, and not on the entropy generated along the process. This new criterion uses the fuel-product (FP) table, a mathematical representation of the thermoeconomic model, as input data. The important characteristic of this new criterion is the use of a new FP table (FP {sup left} {sup angle} {sup S} {sup right} {sup angle} table) which is constructed using energy and exergy of flows. The proposed criterion is applied to a combined cycle and results are compared with the two other criteria. Results show that this criterion is more suitable and rational than the two other criteria. (author)

  11. Covariance-Based Measurement Selection Criterion for Gaussian-Based Algorithms

    Directory of Open Access Journals (Sweden)

    Fernando A. Auat Cheein

    2013-01-01

    Full Text Available Process modeling by means of Gaussian-based algorithms often suffers from redundant information which usually increases the estimation computational complexity without significantly improving the estimation performance. In this article, a non-arbitrary measurement selection criterion for Gaussian-based algorithms is proposed. The measurement selection criterion is based on the determination of the most significant measurement from both an estimation convergence perspective and the covariance matrix associated with the measurement. The selection criterion is independent from the nature of the measured variable. This criterion is used in conjunction with three Gaussian-based algorithms: the EIF (Extended Information Filter, the EKF (Extended Kalman Filter and the UKF (Unscented Kalman Filter. Nevertheless, the measurement selection criterion shown herein can also be applied to other Gaussian-based algorithms. Although this work is focused on environment modeling, the results shown herein can be applied to other Gaussian-based algorithm implementations. Mathematical descriptions and implementation results that validate the proposal are also included in this work.

  12. A model to examine the validity of the 6-month abstinence criterion for liver transplantation.

    Science.gov (United States)

    Yates, W R; Martin, M; LaBrecque, D; Hillebrand, D; Voigt, M; Pfab, D

    1998-04-01

    Six months of abstinence from alcohol is a commonly used criterion for liver transplantation eligibility for patients with alcoholic cirrhosis. There is limited evidence to document the validity of this criterion with regard to risk of alcoholism relapse. Ninety-one patients with alcoholic cirrhosis were interviewed for relapse risk using the High Risk Alcoholism Relapse (HRAR) Scale. The HRAR model can be used to predict relapse risk independent of duration of sobriety and therefore can be used to examine the validity of the 6 months of abstinence criteria in this clinical population. The two methods demonstrated poor to fair agreement. Agreement was highest with a cutoff allowing a 5% 6-month relapse risk when 79% agreement (c = 0.56) was demonstrated between the two methods. Using the 6-month abstinence criterion alone disallows a significant number of candidates who have a low relapse risk based on their HRAR score. The validity of the 6-month abstinence criterion is supported somewhat by comparison with the HRAR model. However, use of the 6-month abstinence criterion alone forces a significant number of patients with a low relapse risk by HRAR to wait for transplant listing. A relapse risk model based on an estimate of alcoholism severity in addition to duration of sobriety may more accurately select patients who are most likely to benefit from liver transplantation. PMID:9581661

  13. A Criterion Based on Closed-loop Pilot-aircraft Systems for Predicting Flying Qualities

    Institute of Scientific and Technical Information of China (English)

    Tan Wenqian; A.V.Efremov; Qu Xiangju

    2010-01-01

    During the process of aircraft design,the mathematical model of pilot control behavior characteristics is always used to predict aircraft flying qualities (FQ).This is one of the important methods to avoid pilot-aircraft adverse coupling.In order to study the FQ criterion based on closedloop pilotaircraft systems,first,an experimental database is built,which includes 40 aircraft dynamics configurations and the corresponding flight simulation results.Second,the mathematical pilot models with a set of different aircraft configurations are obtained by this experimental database.Then,two FQ criteria,NealSmith criterion and Moscow Aviation Institute (MAI) criterion,are analyzed.And the relationship between the FQ level evaluated by actual pilot and the parameters of closedloop pilotaircraft systems is studied.Finally,an improved criterion of aircraft FQ is built based on the above two criteria.This new criterion is further used to predict FQ for four new aircraft dynamics configurations,and the prediction results verify its accuracy and practicability.

  14. Quality criterion to optimize separations in capillary electrophoresis: Application to the analysis of harmala alkaloids.

    Science.gov (United States)

    Tascon, Marcos; Benavente, Fernando; Castells, Cecilia B; Gagliardi, Leonardo G

    2016-08-19

    In capillary electrophoresis (CE), resolution (Rs) and selectivity (α) are criteria often used in practice to optimize separations. Nevertheless, when these and other proposed parameters are considered as an elementary criterion for optimization by mathematical maximization, certain issues and inconsistencies appear. In the present work we analyzed the pros and cons of using these parameters as elementary criteria for mathematical optimization of capillary electrophoretic separations. We characterized the requirements of an ideal criterion to qualify separations within the framework of mathematical optimizations and, accordingly, propose: -1- a new elementary criterion (t') and -2- a method to extend this elementary criterion to compose a global function that simultaneously qualifies many different aspects, also called multicriteria optimization function (MCOF). In order to demonstrate this new concept, we employed a group of six alkaloids with closely related structures (harmine, harmaline, harmol, harmalol, harmane and norharmane). On the basis of this system, we present a critical comparison between the new optimization criterion t' and the former elementary criteria. Finally, aimed at validating the proposed methods, we composed an MCOF in which the capillary-electrophoretic separation of the six model compounds is mathematically optimized as a function of pH as the unique variable. Experimental results subsequently confirmed the accuracy of the model. PMID:27443250

  15. An analytic expression for the sheath criterion in magnetized plasmas with multi-charged ion species

    International Nuclear Information System (INIS)

    The generalized Bohm criterion in magnetized multi-component plasmas consisting of multi-charged positive and negative ion species and electrons is analytically investigated by using the hydrodynamic model. It is assumed that the electrons and negative ion density distributions are the Boltzmann distribution with different temperatures and the positive ions enter into the sheath region obliquely. Our results show that the positive and negative ion temperatures, the orientation of the applied magnetic field and the charge number of positive and negative ions strongly affect the Bohm criterion in these multi-component plasmas. To determine the validity of our derived generalized Bohm criterion, it reduced to some familiar physical condition and it is shown that monotonically reduction of the positive ion density distribution leading to the sheath formation occurs only when entrance velocity of ion into the sheath satisfies the obtained Bohm criterion. Also, as a practical application of the obtained Bohm criterion, effects of the ionic temperature and concentration as well as magnetic field on the behavior of the charged particle density distributions and so the sheath thickness of a magnetized plasma consisting of electrons and singly charged positive and negative ion species are studied numerically

  16. Analytical investigation of an isomerization system using the resonance overlap criterion

    Science.gov (United States)

    Fukuda, Hiroya; Petrosky, Tomio; Konishi, Tetsuro

    2016-09-01

    An analytical procedure to obtain the volume of reactive initial condition in the reactant well is described. The applicability of the well-known Chirikov resonance overlap criterion is tested to determine the boundary between the reactive and unreactive regions of phase space in the reactant well for a classical Hamiltonian system with symmetric double-well potential coupled with a harmonic oscillator. As usual, the system is reduced to the two-dimensional whisker mapping in order to apply the overlap criterion. For the calculation process, the applicability of the overlap criterion is examined in cases where up to period-n (n=1,2,3) resonances are included in the criterion. Theoretical results are compared to numerical simulation through the Davis-Gray unimolecular reaction rate constant. It is found that Chirikov's criterion led to a bad estimation for lower periods up to n=2, but produced a reliable estimation after taking into account higher periods with n=3. However, there are some situations where the agreement including n=3 is still not good. The reasons for this disagreement and the possibilities for improvement of the calculation accuracy are discussed.

  17. A Code Level Based Programmer Assessment and Selection Criterion Using Metric Tools

    Directory of Open Access Journals (Sweden)

    Ezekiel U. Okike

    2014-11-01

    Full Text Available this study presents a code level measurement of computer programs developed by computer programmers using a Chidamber and Kemerer Java metric (CKJM tool and the Myers Briggs Type Indicator (MBTI tool. The identification of potential computer programmers using personality trait factors does not seem to be the best approach without a code level measurement of the quality of programs. Hence the need to evolve a metric tool which measures both personality traits of programmers and code level quality of programs developed by programmers. This is the focus of this study. In this experiment, a set of Java based programming tasks were given to 33 student programmers who could confidently use the Java programming language. The codes developed by these students were analyzed for quality using a CKJM tool. Cohesion, coupling and number of public methods (NPM metrics were used in the study. The choice of these three metrics from the CKJM suite was because they are useful in measuring well designed codes. By examining the cohesion values of classes, high cohesion ranges [0,1] and low coupling imply well designed code. Also number of methods (NPM in a well-designed class is always less than 5 when cohesion range is [0,1]. Results from this study show that 19 of the 33 programmers developed good and cohesive programs while 14 did not. Further analysis revealed the personality traits of programmers and the number of good programs written by them. Programmers with Introverted Sensing Thinking Judging (ISTJ traits produced the highest number of good programs, followed by Introverted iNtuitive Thinking Perceiving (INTP, Introverted iNtuitive Feelingng Perceiving (INTP, and Extroverted Sensing Thinking Judging (ESTJ

  18. Separability Criterion for Arbitrary Multipartite Pure State Based on the Rank of Reduced Density Matrix

    Science.gov (United States)

    Zhao, Chao; Yang, Guo-wu; Li, Xiao-yu

    2016-09-01

    Nowadays, there are plenty of separability criteria which are used to detect entanglement. Many of them are limited to apply for some cases. In this paper, we propose a separability criterion for arbitrary multipartite pure state which is based on the rank of reduced density matrix. It is proved that the rank of reduced density matrices of a multipartite state is closely related to entanglement. In fact it can be used to characterize entanglement. Our separability criterion is a necessary and sufficient condition for detecting entanglement. Furthermore, it is able to help us find the completely separable form of a multipartite pure state according to some explicit examples. Finally it demonstrates that our method are more suitable for some specific case. Our separability criterion are simple to understand and it is operational.

  19. Deduction of plastic work rate per unit volume for unified yield criterion and its application

    Institute of Scientific and Technical Information of China (English)

    ZHAO De-wen; LI Jing; LIU Xiang-hua; WANG Guo-dong

    2009-01-01

    A unified linear expression of plastic work rate per unit volume is deduced from the unified linear yield criterion and the associated flow rule. The expression is suitable for various linear yield loci in the error triangle between Tresca's and twin shear stress yield loci on the π-plane. It exhibits generalization in which the different value of criterion parameter b corresponds to a specific linear formula of plastic work rate per unit volume. Finally, with the unified linear expression of plastic work rate and upper-bound parallel velocity field the strip forging without bulge is successfully analyzed and an analytical result is also obtained. The comparison with traditional solutions shows that when b=1/(1+(√3)) the result is the same as the upper bound result by Mises' yield criterion, and it also is identical to that by slab method with m=1, σ0=0.

  20. Rayleigh Number Criterion for Formation of A-Segregates in Steel Castings and Ingots

    DEFF Research Database (Denmark)

    Rad, M. Torabi; Kotas, Petr; Beckermann, C.

    2013-01-01

    A Rayleigh number-based criterion is developed for predicting the formation of A-segregates in steel castings and ingots. The criterion is calibrated using available experimental data for ingots involving 27 different steel compositions. The critical Rayleigh number above which A-segregates can...... be expected to form is found to be 17 ± 8. The primary source of uncertainty in this critical value is the dendrite arm spacing. The Rayleigh number criterion of the current study is implemented in a casting simulation code and used to predict A-segregates in three case studies involving steel sand castings......, the primary reason for this over-prediction is persumed to be the presence of a central zone of equiaxed grains in the casting sections. A-segregates do not form when the grain structure is equiaxed. © The Minerals, Metals & Materials Society and ASM International 2013...

  1. A MIXED MODE FRACTURE CRITERION BASED ON THE MAXIMUM TANGENTIAL STRESS IN BRITTLE INCLUSION

    Institute of Scientific and Technical Information of China (English)

    Ji Changjiang; Li Zhonghua; Sun Jun

    2005-01-01

    A closed-form solution for predicting the tangential stress of an inclusion located in mixed mode Ⅰ and Ⅱ crack tip field was developed based on the Eshelby equivalent inclusion theory. Then a mixed mode fracture criterion, including the fracture direction and the critical load, was established based on the maximum tangential stress in the inclusion for brittle inclusioninduced fracture materials. The proposed fracture criterion is a function of the inclusion fracture stress, its size and volume fraction, as well as the elastic constants of the inclusion and the matrix material. The present criterion will reduce to the conventional one as the inclusion having the same elastic behavior as the matrix material. The proposed solutions are in good agreement with detailed finite element analysis and measurement.

  2. A Simple Isolation Criterion based on 3D Redshift Space Mapping

    CERN Document Server

    Spector, Oded

    2009-01-01

    We selected a sample of galaxies, extremely isolated in 3D redshift space, based on data from NED and the ongoing ALFALFA HI (21cm) survey. A simple selection criterion was employed: having no neighbors closer than 300 km/s in 3D redshift space. The environments of galaxies, selected using this criterion and NED data alone, were analyzed theoretically using a constrained simulation of the local Universe, and were found to be an order of magnitude less dense than environments around randomly selected galaxies. One third of the galaxies selected using NED data alone did not pass the criterion when tested with ALFALFA data, implying that the use of unbiased HI data significantly improves the quality of the sample.

  3. A risk-based microbiological criterion that uses the relative risk as the critical limit

    DEFF Research Database (Denmark)

    Andersen, Jens Kirk; Nørrung, Birgit; da Costa Alves Machado, Simone;

    2015-01-01

    criteria. The approach requires the availability of a quantitative microbiological risk assessment model to get risk estimates for food products from sampled food lots. By relating these food lot risk estimates to the mean risk estimate associated to a representative baseline data set, a relative risk...... estimate can be obtained. This relative risk estimate then can be compared with a critical value, defined by the criterion. This microbiological criterion based on a relative risk limit is particularly useful when quantitative enumeration data are available and when the prevalence of the microorganism...... of concern is relatively high. The use of the approach is therefore illustrated with an example of Campylobacter in broiler meat. It shows that this microbiological criterion can be applied in practice. An advantage of the method is that the acceptable limit is directly defined in terms of risk, without...

  4. Criterion for DNA melting in the mean-field modified self-consistent phonon theory

    Science.gov (United States)

    Feng, Y.; Prohofsky, E. W.

    1991-04-01

    We have examined the validity of the first-order-perturbation method in calculating eigenfunctions and the criterion for helix melting of mean-field polymers in the modified self-consistent phonon approach (MSPA) theory. It is found that the instability in the self-consistent solution is due to the breakdown of the first-order perturbation. The instability as a criterion for helix melting is therefore techniquely inappropriate. However, the breakdown of the perturbation is due to facts that are directly related to the onset of softening. Previously predicted melting temperatures for various sequence DNA polymers may still represent good estimates to the actual melting temperatures. An alternative criterion is required to define the melting temperature of the polymer DNA double helix in the MSPA theory.

  5. A simplified approach to directly consider intact rock anisotropy in HoekeBrown failure criterion

    Institute of Scientific and Technical Information of China (English)

    Mohamed AIsmael; Hassan FImam; Yasser El-Shayeb

    2014-01-01

    Many rock types have naturally occurring inherent anisotropic planes, such as bedding planes, foliation, or flow structures. Such characteristic induces directional features and anisotropy in rocks’ strength and deformational properties. The HoekeBrown (HeB) failure criterion is an empirical strength criterion widely applied to rock mechanics and engineering. A direct modification to HeB failure criterion to account for rock anisotropy is considered as the base of the research. Such modification introduced a new definition of the anisotropy as direct parameter named the anisotropic parameter (Kb). However, the computation of this parameter takes much experimental work and cannot be calculated in a simple way. The aim of this paper is to study the trend of the relation between the degree of anisotropy (Rc) and the minimum value of anisotropic parameter (Kmin), and to predict the Kmin directly from the uniaxial compression tests instead of triaxial tests, and also to decrease the amount of experimental work.

  6. Application of geometric midline yield criterion to analysis of three-dimensional forging

    Institute of Scientific and Technical Information of China (English)

    ZHAO De-wen; WANG Gen-ji; LIU Xiang-hua; WANG Guo-dong

    2008-01-01

    A kinematically admissible continuous velocity field was proposed for the analysis of three-dimensional forging. The linear yield criterion expressed by geometric midline of error triangle between Tresca and Twin shear stress yield loci on the π-plane, called GM yield criterion for short, was firstly applied to analysis of the velocity field for the forging. The analytical solution of the forging force with the effects of external zone and bulging parameter is obtained by strain rate inner product. Compression tests of pure lead are performed to compare the calculated results with the measured ones. The results show that the calculated total pressures are higher than the measured ones whilst the relative error is no more than 9.5%. It is implied that the velocity field is reasonable and the geometric midline yield criterion is available. The solution is still an upper-bound one.

  7. A study on site release criterion assessment of nuclear power facilites for TRIGA research reactor decommissioning

    International Nuclear Information System (INIS)

    The process of establishing the site release criterion in MARSSIM is a guide which makes a decision if the contamination level of the building in the site meets guide level, so it is able to classify the contamination site with the expected contamination level in facility site as the process to raise the working efficiency with applying to the site facility building of TRIGA research reactor on the progress of the internal decommissioning plan. It is unreasonable to establish the criterion for site recycling so far due to the lack of survey because the decommissioning plan of TRIGA research reactor is still on the progress. But it is able to design process to establish the site recycling criterion according to survey result with using the method to decide survey quantity and location in MARSSIM process guide

  8. Development of a brittle fracture acceptance criterion for the International Atomic Energy Agency (IAEA)

    Energy Technology Data Exchange (ETDEWEB)

    Sorenson, K.B.; Salzbrenner, R. (Sandia National Labs., Albuquerque NM (United States)); Nickell, R.E.

    1993-01-01

    An effort has been undertaken to develop a brittle fracture acceptance criterion for structural components of nuclear material transportation casks. The need for such a criterion was twofold. First, new generation cask designs have proposed the use of ferritic steels and other materials to replace the austenitic stainless steel commonly used for structural components in transport casks. Unlike austenitic stainless steel which fails in a high-energy absorbing, ductile tearing mode, it is possible for these candidate materials to fail via brittle fracture when subjected to certain combinations of elevated loading rates and low temperatures. Second, there is no established brittle fracture criterion accepted by the regulatory community that covers a broad range of structural materials. Although the existing IAEA Safety Series no.37 addressed brittle fracture, its the guidance was dated and pertained only to ferritic steels. Consultant's Services Meetings held under the auspices of the IAEA have resulted in a recommended brittle fracture criterion. The brittle fracture criterion is based on linear elastic fracture mechanics, and is the result of a consensus of experts from six participating IAEA-member countries. The brittle fracture criterion allows three approaches to determine the fracture toughness of the structural material. The three approaches present the opportunity to balance material testing requirements and the conservatism of the material's fracture toughness which must be used to demonstrate resistance to brittle fracture. This work has resulted in a revised Appendix IX to Safety Series no.37 which will be released as an IAEA Technical Document within the coming year. (author).

  9. Development of a brittle fracture acceptance criterion for the International Atomic Energy Agency (IAEA)

    Energy Technology Data Exchange (ETDEWEB)

    Sorenson, Ken B.; Salzbrenner, Richard [Sandia National Labs., Albuquerque, NM (United States); Nickell, Robert E. [Applied Science and Technology, Inc., Poway, CA (United States)

    1992-01-01

    An effort has been undertaken to develop a brittle fracture acceptance criterion for structural components of nuclear material transportation casks. The need for such a criterion was twofold. First, new generation cask designs have proposed the use of ferritic steels and other materials to replace the austenitic stainless steel commonly used for structural components in transport casks. Unlike austenitic stainless steel which fails in a high-energy absorbing, ductile tearing mode, it is possible for these candidate materials to fail via brittle fracture when subjected to certain combinations of elevated loading rates and low temperatures. Second, there is no established brittle fracture criterion accepted by the regulatory community that covers a broad range of structural materials. Although the existing IAEA Safety Series {number sign}37 addressed brittle fracture, its the guidance was dated and pertained only to ferritic steels. Consultant's Services Meetings held under the auspices of the IAEA have resulted in a recommended brittle fracture criterion. The brittle fracture criterion is based on linear elastic fracture mechanics, and is the result of a consensus of experts from six participating IAEA-member countries. The brittle fracture criterion allows three approaches to determine the fracture toughness of the structural material. The three approaches present the opportunity to balance material testing requirements and the conservatism of the material's fracture toughness which must be used to demonstrate resistance to brittle fracture. This work has resulted in a revised Appendix IX to Safety Series {number sign}37 which will be released as an IAEA Technical Document within the coming year.

  10. Effects of successive relearning on recall: Does relearning override the effects of initial learning criterion?

    Science.gov (United States)

    Vaughn, Kalif E; Dunlosky, John; Rawson, Katherine A

    2016-08-01

    Retrieval practice improves memory for many kinds of materials, and numerous factors moderate the benefits of retrieval practice, including the amount of successful retrieval practice (referred to as the learning criterion). In general, the benefits of retrieval practice are greater with more than with less successful retrieval practice; however, learning items to a higher (vs. lower) criterion requires more time and effort. If students plan on relearning material in a subsequent study session, does the benefit of learning to a higher criterion during an initial session persist? In Session 1, participants studied and successfully recalled Swahili-English word pairs one, two, three, four, five, six, or seven times. In subsequent sessions, all of the pairs were relearned to a criterion of one correct recall at one-week intervals across four or five successive relearning sessions. Experiments 1 and 2 revealed that the substantial benefits of learning to a higher initial criterion during the first session do not persist across relearning sessions. This relearning-override effect was also demonstrated in Experiment 2 after a one-month retention interval. The implications of relearning-override effects are important for theory and for education. For theories of test-enhanced learning, they support the predictions of one theory and appear inconsistent with the predictions of another. For education, if relearning is to occur, using extra time to learn to a higher initial learning criterion is not efficient. Instead, students should devote their time to subsequent spaced relearning sessions, which produce substantial gains in recall performance. PMID:27027887

  11. Childhood trauma and personality disorder criterion counts: a co-twin control analysis.

    Science.gov (United States)

    Berenz, Erin C; Amstadter, Ananda B; Aggen, Steven H; Knudsen, Gun Peggy; Reichborn-Kjennerud, Ted; Gardner, Charles O; Kendler, Kenneth S

    2013-11-01

    Correlational studies consistently report relationships between childhood trauma (CT) and most personality disorder (PD) criteria and diagnoses. However, it is not clear whether CT is directly related to PDs or whether common familial factors (i.e., shared environment and/or genetic factors) better account for that relationship. The current study used a cotwin control design to examine support for a direct effect of CT on PD criterion counts. Participants were from the Norwegian Twin Registry (N = 2,780), including a subset (n = 898) of twin pairs (449 pairs, 45% monozygotic [MZ]) discordant for CT meeting DSM-IV Posttraumatic Stress Disorder Criterion A. All participants completed the Norwegian version of the Structured Interview for DSM-IV Personality. Significant associations between CT and all PD criterion counts were detected in the general sample; however, the magnitude of observed effects was small, with CT accounting for no more than approximately 1% of variance in PD criterion counts. A significant, yet modest, interactive effect was detected for sex and CT on Schizoid and Schizotypal PD criterion counts, with CT being related to these disorders among women but not men. After common familial factors were accounted for in the discordant twin sample, CT was significantly related to Borderline and Antisocial PD criterion counts, but no other disorders; however, the magnitude of observed effects was quite modest (r2 = .006 for both outcomes), indicating that the small effect observed in the full sample is likely better accounted for by common genetic and/or environmental factors. CT does not appear to be a key factor in PD etiology.

  12. Instability Criterion of One-Dimensional Detonation Wave with Three-Step Chain Branching Reaction Model

    Institute of Scientific and Technical Information of China (English)

    TENG Hong-Hui; JIANG Zong-Lin

    2011-01-01

    @@ One-dimensional detonation waves are simulated with the three-step chain branching reaction model, and the instability criterion is studied.The ratio of the induction zone length and the reaction zone length may be used to decide the instability, and the detonation becomes unstable with the high ratio.However, the ratio is not invariable with different heat release values.The critical ratio, corresponding to the transition from the stable detonation to the unstable detonation, has a negative correlation with the heat release.An empirical relation of the Chapman-Jouguet Mach number and the length ratio is proposed as the instability criterion.

  13. Valence electron structure of cast iron and graphltization behaviour criterion of elements

    Institute of Scientific and Technical Information of China (English)

    刘志林; 李志林; 孙振国; 杨晓平; 陈敏

    1995-01-01

    The valence electron structure of common alloy elements in phases of cast iron is calculated- The relationship between the electron structure of alloy elements and equilibrium, non-equilibrium solidification and graphitization is revealed by defining the bond energy of the strongest bond in a phase as structure formation factor S. A criterion of graphitization behaviour of elements is advanced with the critical value of the structure formation factor of graphite and the n of the strongest covalent bond in cementite. It is found that this theory conforms to practice very well when the criterion is applied to the common alloy elements.

  14. Application of Fisher method to discriminating earthquakes and explosions using criterion mb/Ms

    Institute of Scientific and Technical Information of China (English)

    BIAN Yin-ju

    2005-01-01

    We try to give a quantitative and global discrimination function by studying mb/Ms data using Fisher method that is a kind of pattern recognition methods. The reliability of the function is also analyzed. The results show that this criterion works well and has a global feature, which can be used as first-level filtering criterions in event identification. The quantitative and linear discrimination function makes it possible to identify events automatically and achieve the goal to react the events quickly and effectively.

  15. Application of the cubic polynomial strength criterion to the failure analysis of composite materials

    Science.gov (United States)

    Tennyson, R. C.; Nanyaro, A. P.; Wharram, G. E.

    1980-01-01

    A comparative failure analysis is presented based on the application of quadratic and cubic forms of the tensor polynomial lamina strength criterion to various composite structural configurations in a plane stress state. Failure loads have been predicted for off-angle laminates under simple loading conditions and for symmetric-balanced laminates subject to varying degrees of biaxial tension, including configurations subject to multimode failures. Some experimental data are also provided to support these calculations. From these results, the necessity of employing a cubic strength criterion to accurately predict the failure of composite laminae is demonstrated.

  16. Validity criterion of the radiative Fourier law for an absorbing and scattering medium.

    Science.gov (United States)

    Gomart, Hector; Taine, Jean

    2011-02-01

    For radiative heat transfer applications, in particular in homogenized phases of porous media, an exhaustive and accurate validity criterion of the radiative Fourier law, depending only on the logarithmic derivative of the temperature field and an effective absorption coefficient, accounting for possible multiple scattering phenomena, has been established for a semitransparent medium. This effective absorption coefficient is expressed as a function of the absorption coefficient, the albedo, and the scattering asymmetry parameter. The criterion can be applied to semitransparent media that do not follow Beer's laws related to extinction, absorption, and scattering. PMID:21405835

  17. Formation law and criterion of nebulous macroscopic segregation in ZL205A alloy castings

    Institute of Scientific and Technical Information of China (English)

    Li Yusheng; Zhai Hu; Feng Zhijun; Qu Xuahui

    2008-01-01

    The appearance of macroscopic segregation in ZL205A alloy castings bears a super resemblance to the appearance of shrinkage porosity, and the chemical composition of the segregation is Al2Cu whose microstructure is in the form of dentrite or skeleton crystal. According to the characteristic of nebulous segregation, the formation process could be divided into two steps by the eutectic temperature of Al2Cu. Then a criterion for each of the two steps is brought forward on the basis of the shrinkage porosity criterion of low pressure casting.

  18. On Verification of the New Criterion of Adiabaticity by Numerical Simulation of Acoustic Propagation through the Polar Front

    Institute of Scientific and Technical Information of China (English)

    WANG Y.Y.; SHANG E. C.

    2002-01-01

    To assess the adiabaticity of acoustic propagation in the ocean is very important for acoustic field calculation(forward problem) and tomographic retrieving (inverse problem). A new criterion of adiabaticity is proposed recently (Shang et al., 2001). In this paper, numerical simulation has been conducted for acoustic propagation through the Polar Front to verify the new criterion. Numerical results on the f (frequency) -m (mode number) plan demonstrate that the new criterion works very well for this extremely non-gradual ocean structure.

  19. Relationships between Classroom Schedule Types and Performance on the Algebra I Criterion-Referenced Test

    Science.gov (United States)

    Murray, Gregory V.; Moyer-Packenham, Patricia S.

    2014-01-01

    One option for length of individual mathematics class periods is the schedule type selected for Algebra I classes. This study examined the relationship between student achievement, as indicated by Algebra I Criterion-Referenced Test scores, and the schedule type for Algebra I classes. Data obtained from the Utah State Office of Education included…

  20. A New Inexactness Criterion for Approximate Logarithmic-Quadratic Proximal Methods

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Recently, a class of logarithmic-quadratic proximal (LQP) methods was introduced by Auslender, Teboulle and Ben-Tiba. The inexact versions of these methods solve the sub-problems in each iteration approximately. In this paper, we present a practical inexactness criterion for the inexact version of these methods.

  1. Reviewing Employee Turnover: Focusing on Proximal Withdrawal States and an Expanded Criterion

    Science.gov (United States)

    Hom, Peter W.; Mitchell, Terence R.; Lee, Thomas W.; Griffeth, Rodger W.

    2012-01-01

    We reconceptualize employee turnover to promote researchers' understanding and prediction of why employees quit or stay in employing institutions. A literature review identifies shortcomings with prevailing turnover dimensions. In response, we expand the conceptual domain of the turnover criterion to include multiple types of turnover (notably,…

  2. A new criterion for assessing discriminant validity in variance-based structural equation modeling

    NARCIS (Netherlands)

    Henseler, J.; Ringle, Christian M.; Sarstedt, Marko

    2015-01-01

    Discriminant validity assessment has become a generally accepted prerequisite for analyzing relationships between latent variables. For variance-based structural equation modeling, such as partial least squares, the Fornell-Larcker criterion and the examination of cross-loadings are the dominant app

  3. Improvement of the termination criterion for subdivision of the rational Bézier curves

    Institute of Scientific and Technical Information of China (English)

    章仁江; 王国瑾

    2003-01-01

    By using some elementary inequalities, authors in this paper makes further improvement for estimating the heights of Bézier curve and rational Bézier curve. And the termination criterion for subdivision of the rational Bézier curve is also improved. The conclusion of the extreme value problem is thus further confirmed.

  4. A refined empirical stability criterion for nonlinear Schroedinger solitons under spatiotemporal forcing

    CERN Document Server

    Mertens, Franz G; Barashenkov, I V; Bishop, A R

    2011-01-01

    We investigate the dynamics of travelling oscillating solitons of the cubic NLS equation under an external spatiotemporal forcing of the form $f(x,t) = a \\exp[iK(t)x]$. For the case of time-independent forcing a stability criterion for these solitons, which is based on a collective coordinate theory, was recently conjectured. We show that the proposed criterion has a limited applicability and present a refined criterion which is generally applicable, as confirmed by direct simulations. This includes more general situations where $K(t)$ is harmonic or biharmonic, with or without a damping term in the NLS equation. The refined criterion states that the soliton will be unstable if the "stability curve" $p(\\v)$, where $p(t)$ and $\\v(t)$ are the normalized momentum and the velocity of the soliton, has a section with a negative slope. Moreover, for the case of constant $K$ and zero damping we use the collective coordinate solutions to compute a "phase portrait" of the soliton where its dynamics is represented by tw...

  5. Nonsuicidal self-injury disorder: Does Criterion B add diagnostic utility?

    Science.gov (United States)

    Brausch, Amy M; Muehlenkamp, Jennifer J; Washburn, Jason J

    2016-10-30

    The current paper evaluates Criterion B for Non-Suicidal Self-Injury Disorder, which states that non-suicidal self-injury (NSSI) must occur for at least one function. The majority of individuals who engage in NSSI report at least one function, so it is unclear if Criterion B provides diagnostic utility in individuals who already meet Criterion A (i.e., NSSI occurring on 5 or more days in the past 12 months). This paper compared individuals meeting Criterion A (threshold group) to those with 1-4 acts of NSSI in the past year (subthreshold group) in two different samples. The first sample included 217 undergraduate students, and the second sample included 1082 individuals from a behavioral health hospital, all with past-year NSSI. The majority of both samples reported at least one function of NSSI (99%). For the undergraduate sample, the number of and level of endorsement of functions were similar across threshold and subthreshold groups. For the behavioral health sample, the threshold group endorsed significantly more functions for NSSI and greater endorsement of affect regulation, self-punishment, and toughness compared to the subthreshold group. While some differences were found between NSSI groups, overall endorsement of functions for NSSI appears to be a universal characteristic regardless of NSSI frequency. PMID:27479110

  6. Recognizing cat-eye targets with dual criterions of shape and modulation frequency

    Institute of Scientific and Technical Information of China (English)

    Ximing Ren; Li Li

    2011-01-01

    We present an image recognition method to distinguish targets with cat-eye effect from the dynamic background based on target shape and modulation frequency. Original image sequences to be processed are acquired through an imaging mechanism that utilizes a pulsed laser as active illuminator and an industrial camera as detection device. There are two criterions to recognize a target: one exploits shape priors and the other is the active illuminator's modulation frequency. The feasibility of the proposed method and its superiority over the single criterion method have been demonstrated by practical experiments.%@@ We present an image recognition method to distinguish targets with cat-eye effect from the dynamic background based on target 8hape and modulation frequency.Original image sequences to be processed are acquired through an imaging mechanism that utilizes a pulsed laser as active illuminator and an industrialcamera as detection device.There are two criterions to recognize a target: one exploits shape prior8 and the other is the active illuminator's modulation frequency.The feasibility of the proposed method and its superiority over the single criterion method have been demonstrated by practical experiments.

  7. Predicting ethnic and racial discrimination: a meta-analysis of IAT criterion studies.

    Science.gov (United States)

    Oswald, Frederick L; Mitchell, Gregory; Blanton, Hart; Jaccard, James; Tetlock, Philip E

    2013-08-01

    This article reports a meta-analysis of studies examining the predictive validity of the Implicit Association Test (IAT) and explicit measures of bias for a wide range of criterion measures of discrimination. The meta-analysis estimates the heterogeneity of effects within and across 2 domains of intergroup bias (interracial and interethnic), 6 criterion categories (interpersonal behavior, person perception, policy preference, microbehavior, response time, and brain activity), 2 versions of the IAT (stereotype and attitude IATs), 3 strategies for measuring explicit bias (feeling thermometers, multi-item explicit measures such as the Modern Racism Scale, and ad hoc measures of intergroup attitudes and stereotypes), and 4 criterion-scoring methods (computed majority-minority difference scores, relative majority-minority ratings, minority-only ratings, and majority-only ratings). IATs were poor predictors of every criterion category other than brain activity, and the IATs performed no better than simple explicit measures. These results have important implications for the construct validity of IATs, for competing theories of prejudice and attitude-behavior relations, and for measuring and modeling prejudice and discrimination. PMID:23773046

  8. A proposal for an international brittle fracture acceptance criterion for nuclear material transport cask applications

    Energy Technology Data Exchange (ETDEWEB)

    Sorenson, K.B.; Salzbrenner, R.J.; Nickell, R.E.

    1989-01-01

    This paper presents a fundamental basis for a brittle fracture acceptance criterion, examine several existing criteria and propose examples for consideration as international brittle fracture acceptance criteria. The proposed criteria are intended to stimulate discussion in order to advance the development of a consensus approach. 8 refs., 1 fig., 1 tab.

  9. Procedures and Issues in the Validation of Criterion-Referenced Tests.

    Science.gov (United States)

    Klein, Stephen P.; Kosecoff, Jacqueline P.

    Four common uses for criterion-referenced tests (CRT) are outlined: describing student achievement, improving curriculum development, being sensitive indicators of the effects of instruction, and facilitating classroom management decisions. These uses parallel various forms of empirically establishing the content, concurrent, and predictive…

  10. Design criterion for inclined planar radomes on radar corner reflectors used for spaceborne SAR calibration

    Science.gov (United States)

    Keen, K. M.

    1985-06-01

    Larger corner reflector ground targets currently planned for spaceborne SAR calibration will require planar A-sandwich radome covers for weather protection and mechanical stability. The radomes must be inclined with respect to reflector apertures, however, to avoid scattering cross-section uncertainties in the target beam peak direction. A criterion for inclination angle is derived here.

  11. New Invariants and Separability criterion of the Mixed States Bipartite Case

    CERN Document Server

    Chen, H

    2001-01-01

    We introduce algebraic sets in the complex linear spaces for the mixed states in bipartite quantum systems as their invariants under local operations. The algebraic set of the mixed state is the union of the linear subspaces if the mixed state is separable. Some examples are given and studied based on our criterion

  12. New Invariants and Separability Criterion of the Mixed States Multipartite Case

    CERN Document Server

    Chen, H

    2001-01-01

    We introduce algebraic set in the complex linear spaces for the mixed states in multipartite quantum systems as their invariants under local operations. The algebraic set has to be the union of the linear subspaces if the state is separable. Some examples are studied based on our criterion

  13. CO2 absorption in carbonate/bicarbonate solutions : The Danckwerts-criterion revisited

    NARCIS (Netherlands)

    Cents, A. H. G.; Brilman, D. W. F.; Versteeg, G. F.

    2005-01-01

    In industrial applications CO2 is frequently removed from gas streams at elevated pressures by absorption and subsequent chemical reaction in carbonate/bicarbonate solutions (e.g. Benfield process). The criterion that determines whether or not this reaction can be regarded as pseudo-first order is g

  14. Evaluation of Self-Perceptions of Creativity: Is It a Useful Criterion?

    Science.gov (United States)

    Reiter-Palmon, Roni; Robinson-Morral, Erika J.; Kaufman, James C.; Santo, Jonathan B.

    2012-01-01

    Self-evaluations or self-perceptions of creativity have been used in the past both as predictors of creative performance and as criteria. Four measures utilizing self-perceptions of creativity were assessed for their usefulness as criterion measures of creativity. Analyses provided evidence of domain specificity of self-perceptions. The scales…

  15. SHARP CRITERIONS OF GLOBAL EXISTENCE AND COLLAPSE FOR COUPLED NONLINEAR SCHR(O)DINGER EQUATIONS

    Institute of Scientific and Technical Information of China (English)

    Gan Zaihui; Zhang Jian

    2004-01-01

    In this paper, a series of sharp criterions of global existence and collapse for coupled nonlinear Schrodinger equations are derived out in terms of the characteristics of the ground state and the local theories. And the conclusion that how small the initial data are, the global solutions exist is proved.

  16. Modelling and simulation of A-segregates in steel castings using a thermal criterion function

    DEFF Research Database (Denmark)

    Kotas, Petr; Hattel, Jesper Henri

    2012-01-01

    simulation software package. It is then used for predicting A segregates inside a large steel casting, i.e. a forging ram. In part I, experimental data obtained from a foundry serve to validate the given criterion and to evaluate the critical value for A segregate initiation for one alloy composition...

  17. Tightening the Dutch coffee shop policy: Evaluation of the private club and the residence criterion

    NARCIS (Netherlands)

    M.M.J. van Ooyen-Houben; B. Bieleman; D.J. Korf

    2016-01-01

    Background The Dutch coffee shop policy was tightened in 2012. Two additional criteria that coffee shops must adhere to in order for them to be tolerated came into force: the private club and the residence criterion. Coffee shops were only permitted to give access to members and only residents of th

  18. PROFESSIONAL IMPROVEMENT OF THE HIGH SCHOOL TEACHERS OF THE HUMANITARIAN SPECIALTIES: REFLEXIVE-TRANSCENDENT CRITERION

    OpenAIRE

    Tsvetkova, Ganna

    2014-01-01

    The problems of professional self-development of teachers of the Humanities are considered, formedness of the reflective-transcendental criterion as one of the essential features of teacher’s abilities of the higher school is revealed in the article.

  19. The cut-off criterion for a positive hydrogen breath test in children: a reappraisal.

    Science.gov (United States)

    Solomons, N W; Barillas, C

    1986-01-01

    Seventy-three preschool children with adequate nutritional status underwent interval-sampling, 3-hour breath-hydrogen carbohydrate absorption tests after consuming either 240 ml of intact milk (containing 12 g of lactose) or the same volume of milk with 90-95% of its lactose prehydrolyzed in vitro (containing less than 1 g lactose, with the remaining sugar as glucose and galactose). Results were examined in a reappraisal of the cut-off criterion for the rise of breath H2 concentration signifying biologically incomplete absorption. If the greater than or equal to 10-ppm criterion advocated by some investigators is used, 83% of our subjects would have been classified as incomplete lactose digesters and 30% would have their tests with the monosaccharide-rich milk classified as positive. With the greater than or equal to 20 ppm criterion used in our laboratory and others, the prevalence of lactose maldigestion in the sample becomes 60% and only 4% of subjects have apparent monosaccharide absorption, 96% having a rise below the cut-off level with prehydrolyzed milk. At least in Guatemalan preschoolers, the 20-ppm criterion for a positive breath H2 test provides a superior specificity-sensitivity balance and more reasonable diagnostic conclusions. PMID:3794911

  20. COMPARATIVE CRITERION OF ALTERNATIVE VARIANTS OF THE FREIGHT CAR PARK MANAGEMENT

    Directory of Open Access Journals (Sweden)

    L. V. Marcenjuk

    2010-06-01

    Full Text Available The article describes the optimal criterion for different variants of management of freight car stocks. The authors came to the conclusion that in order to achieve the biggest profit the variant of reformation with getting the greatest net discount income is most effective.

  1. From weak to strong L1-convergence by an oscillation restriction criterion of BMO type

    NARCIS (Netherlands)

    Balder, E.J.

    2001-01-01

    Recently, Girardi gave acharacterization of relative strong L 1 R-compactness in terms of relative weak L 1 R-compactness and the Bocce criterion [18]. Here this result is generalized and extended by presenting a less stringent oscillation restriction condition (ORC) which enforces the transcendence

  2. Responder Status Criterion for Stepped Care Trauma-Focused Cognitive Behavioral Therapy for Young Children

    Science.gov (United States)

    Salloum, Alison; Scheeringa, Michael S.; Cohen, Judith A.; Storch, Eric A.

    2015-01-01

    Background: In order to develop Stepped Care trauma-focused cognitive behavioral therapy (TF-CBT), a definition of early response/non-response is needed to guide decisions about the need for subsequent treatment. Objective: The purpose of this article is to (1) establish criterion for defining an early indicator of response/non-response to the…

  3. Criterion-Referenced Test (CRT) Items for Air Conditioning, Heating and Refrigeration.

    Science.gov (United States)

    Davis, Diane, Ed.

    These criterion-referenced test (CRT) items for air conditioning, heating, and refrigeration are keyed to the Missouri Air Conditioning, Heating, and Refrigeration Competency Profile. The items are designed to work with both the Vocational Instructional Management System and Vocational Administrative Management System. For word processing and…

  4. HEAT PUMP GAS COOLER CONTROL USING CRITERION OF MINIMUM OF EXERGY LOSSSES

    Directory of Open Access Journals (Sweden)

    Sit M.L.

    2014-08-01

    Full Text Available This paper focuses on the development of the criterion of optimality of transients of the control system, based on the minimum of exergy losses in the gas cooler of carbon dioxide heat pump. It is noted that the exergy quality criterion has a clear physical meaning, as compared with the integral quadratic criterion in which the choice of the coefficients in the integrand is not justified. Mathematic model of heat exchanger is obtained using the method of solving differential equations, without going to the irrational transfer functions. The model is reduced to transfer functions of the first and second order with the delay. The continuous temperature control system of heat pump gas cooler is considered. It is shown, that one of the versions of the control system for the minimization of the proposed criterion can be a combined control system using both the principle of the negative feedback and the principle of the invariance related to a number of disturbances affecting the processes of heat transfer in the heat exchanger.

  5. A Joint Criterion for Reachability and Observability of Nonuniformly Sampled Discrete Systems

    OpenAIRE

    Fúster-Sabater, Amparo

    2010-01-01

    A joint characterization of reachability (controllability) and observability (constructibility) for linear SISO nonuniformly sampled discrete systems is presented. The work generalizes to the nonuniform sampling the criterion known for the uniform sampling. Emphasis is on the nonuniform sampling sequence, which is believed to be an additional element for analysis and handling of discrete systems.

  6. Simpler criterion on W state for perfect quantumstate splitting and quantum teleportation

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    A simpler criterion is presented to judge whether a W state can be taken as quantum channel forperfectly splitting or teleporting an arbitrary single-qubit state. If the W state is usable,the detailed manipulations in the two quantum information processes are amply shown. Moreover,some relevant discussions are made.

  7. The calculation of the instability criterion for a uniform viscous flow past an oil boom

    International Nuclear Information System (INIS)

    An important problem in oil spill containment by booms is the instability of the oil-water interface at the boom. This instability, which represents the conditions under which oil can escape under the boom, is investigated. A viscous flow model for thin slicks in two dimensions is developed. To understand the effect of viscosity on the instability criterion, the full Navier-Stokes equations are solved by the fractional-step method in time-domain to determine the pressure gradients along the boom. The numerically obtained viscous instability criterion is then compared with the potential flow and experimentally determined instability criteria. Analytical instability formulas for potential flows are based on the velocity potentials for attached and detached flows due to uniform current past a flat plate in finite and infinite water depths. The results show that the viscous flow model predicts a larger region of stability. It is numerically determined from the instability criterion that the oil droplets at the boom between the free surface and down to about 40 percent of the boom height can never escape, regardless of the current strength. It is also shown that the instability criterion depends weakly on the high Reynolds number. Reanalysis of the available experimental data confirms these findings

  8. easyCBM® Reading Criterion Related Validity Evidence: Grades K-1. Technical Report #1309

    Science.gov (United States)

    Lai, Cheng-Fei; Alonzo, Julie; Tindal, Gerald

    2013-01-01

    In this technical report, we present the results of a study to gather criterion-related evidence for Grade K-1 easyCBM® reading measures. We used correlations to examine the relation between the easyCBM® measures and other published measures with known reliability and validity evidence, including the Dynamic Indicators of Basic Early Literacy…

  9. easyCBM® Reading Criterion Related Validity Evidence: Grades 2-5. Technical Report #1310

    Science.gov (United States)

    Lai, Cheng-Fei; Alonzo, Julie; Tindal, Gerald

    2013-01-01

    In this technical report, we present the results of a study to gather criterion-related evidence for Grade 2-5 easyCBM® reading measures. We used correlations to examine the relation between the easyCBM® measures and other published measures with known reliability and validity evidence, including the Gates-MacGinitie Reading Tests and the Dynamic…

  10. A DELAY-DEPENDENT STABILITY CRITERION FOR NONLINEAR STOCHASTIC DELAY-INTEGRO-DIFFERENTIAL EQUATIONS

    Institute of Scientific and Technical Information of China (English)

    Niu Yuanling; Zhang Chengjian; Duan Jinqiao

    2011-01-01

    A type of complex systems under both random influence and memory effects is considered.The systems are modeled by a class of nonlinear stochastic delay-integrodifferential equations.A delay-dependent stability criterion for such equations is derived under the condition that the time lags are small enough.Numerical simulations are presented to illustrate the theoretical result.

  11. 46 CFR 70.05-20 - Gross tonnage as a criterion for requirements.

    Science.gov (United States)

    2010-10-01

    ... Section 70.05-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS GENERAL PROVISIONS Application § 70.05-20 Gross tonnage as a criterion for requirements. (a) The... devices in the basic gross tonnage formulation, will circumvent or be incompatible with the application...

  12. Using the EMD method to determine fault criterion for medium-low pressure gas regulators

    Science.gov (United States)

    Hao, Xuejun; Liu, Qiang; Yang, Guobin; Du, Yi

    2015-11-01

    By extracting the outlet pressure data of gas regulators, this paper uses the EMD toolbox of the MATLAB software, which can perform data decomposition and the Hilbert-Huang Transform to find the rules with fault data. Eventually, the medium-low pressure gas regulator fault criterion can be established.

  13. Criterion-Referenced Measurement (CRM) in the Initial Acquisition of a Psychomotor Skill with Exceptional Children

    Science.gov (United States)

    Muhich, Dolores

    1976-01-01

    Criterion Referenced Measurement (CRM) in the initial acquisition of the psychomotor skill of typewriting demonstrated speed gains from 8 hours of instruction distributed over a 6-week interval for 4 male adolescent underachievers of above- and below-average intelligence. (Author)

  14. Delay-Dependent Exponential Stability Criterion for BAM Neural Networks with Time-Varying Delays

    Institute of Scientific and Technical Information of China (English)

    Wei-Wei Su; Yi-Ming Chen

    2008-01-01

    By employing the Lyapunov stability theory and linear matrix inequality (LMI) technique, delay dependent stability criterion is derived to ensure the exponential stability of bi-directional associative memory (BAM) neural networks with time-varying delays. The proposed condition can be checked easily by LMI control toolbox in Matlab. A numerical example is given to demonstrate the effectiveness of our results.

  15. On heuristic bi-criterion methods for semi-obnoxious facility location

    NARCIS (Netherlands)

    Ortigosa, P.M.; Hendrix, E.M.T.; Rendondo, J.L.

    2015-01-01

    Locating a semi-obnoxious facility, like an airport or correctional center is typically a bi-criterion problem combining a convex objective function representing minimum transportation cost with a multi-extremal objective function representing the non-desirable part of the facility. Generic one or b

  16. Corrections for criterion reliability in validity generalization: The consistency of Hermes, the utility of Midas

    Directory of Open Access Journals (Sweden)

    Jesús F. Salgado

    2016-04-01

    Full Text Available There is criticism in the literature about the use of interrater coefficients to correct for criterion reliability in validity generalization (VG studies and disputing whether .52 is an accurate and non-dubious estimate of interrater reliability of overall job performance (OJP ratings. We present a second-order meta-analysis of three independent meta-analytic studies of the interrater reliability of job performance ratings and make a number of comments and reflections on LeBreton et al.s paper. The results of our meta-analysis indicate that the interrater reliability for a single rater is .52 (k = 66, N = 18,582, SD = .105. Our main conclusions are: (a the value of .52 is an accurate estimate of the interrater reliability of overall job performance for a single rater; (b it is not reasonable to conclude that past VG studies that used .52 as the criterion reliability value have a less than secure statistical foundation; (c based on interrater reliability, test-retest reliability, and coefficient alpha, supervisor ratings are a useful and appropriate measure of job performance and can be confidently used as a criterion; (d validity correction for criterion unreliability has been unanimously recommended by "classical" psychometricians and I/O psychologists as the proper way to estimate predictor validity, and is still recommended at present; (e the substantive contribution of VG procedures to inform HRM practices in organizations should not be lost in these technical points of debate.

  17. Frequency-Domain Criterion for the Speech Distortion Weighted Multichannel Wiener Filter for Robust Noise Reduction

    OpenAIRE

    Doclo, Simon; Spriet, Ann; Wouters, Jan; Moonen, Marc

    2007-01-01

    Frequency-Domain Criterion for the Speech Distortion Weighted Multichannel Wiener Filter for Robust Noise Reduction correspondence: Corresponding author. Tel.: +32 16 32 1899; fax: +32 16 32 1970. (Doclo, Simon) (Doclo, Simon) Katholieke Universiteit Leuven, Dept. of Electrical Engineering (ESAT - SCD) - Kasteelpark Arenberg 10 bus 2446--> , 3001 Heverlee (Leuven)--> - BELGIUM (Doclo, Simon) B...

  18. Role of Covariance Correlation Tensor in Establishment of Criterion of Quantum Entanglement

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    This article discusses the role of covariance correlation tensor in the establishment of the criterion of quantum entanglement. It gives a simple example to show the powerfulness in the treatment of quantum dense coding,and illustrates the fact that this method also provides theoretical basis for establishing corresponding knotted pictures.

  19. The Spirit Is Willing, but the Flesh Is Weak: Criterion-Referenced Testing in Wyoming.

    Science.gov (United States)

    Moore, Alan D.; Cross, Tracy L.

    The perceived needs of public school personnel in Wyoming with respect to the development and use of criterion-referenced tests (CRTs) as part of a district-wide testing program were assessed using a survey designed for the study. Questionnaires were sent to all superintendents, assistant superintendents, and curriculum directors in the state. Of…

  20. The Effects of Misleading and Inconsistent Postevent Information on Children's Recollections of Criterion-Learned Information.

    Science.gov (United States)

    Lee, Kerry; Bussey, Kay

    1999-01-01

    Examined effects of misleading or inconsistent post-event information on 7-year olds' recollections. Misinformation was administered on one or three occasions two days after learning a target game. Found that three weeks later, even criterion-learned information could be affected detrimentally by misinformation exposure. Children given…

  1. A relaxed criterion for contraction theory: application to an underwater vehicle observer

    DEFF Research Database (Denmark)

    Jouffroy, Jerome

    the Jacobian is not uniformly negative definite but fulfils some weaker conditions. Intended as an illustrative example, a nonlinear underwater vehicle observer, which Jacobian is not uniformly negative definite, is presented and proven to be exponentially convergent using the new criterion....

  2. Effects on Scale Linking of Different Definitions of Criterion Functions for the IRT Characteristic Curve Methods

    Science.gov (United States)

    Kim, Seonghoon; Kolen, Michael J.

    2007-01-01

    Under item response theory, the characteristic curve methods (Haebara and Stocking-Lord methods) are used to link two ability scales from separate calibrations. The linking methods use their respective criterion functions that can be defined differently according to the symmetry- and distribution-related schemes. The symmetry-related scheme…

  3. Direct numerical simulations of non-premixed ethylene-air flames: Local flame extinction criterion

    KAUST Repository

    Lecoustre, Vivien R.

    2014-11-01

    Direct Numerical Simulations (DNS) of ethylene/air diffusion flame extinctions in decaying two-dimensional turbulence were performed. A Damköhler-number-based flame extinction criterion as provided by classical large activation energy asymptotic (AEA) theory is assessed for its validity in predicting flame extinction and compared to one based on Chemical Explosive Mode Analysis (CEMA) of the detailed chemistry. The DNS code solves compressible flow conservation equations using high order finite difference and explicit time integration schemes. The ethylene/air chemistry is simulated with a reduced mechanism that is generated based on the directed relation graph (DRG) based methods along with stiffness removal. The numerical configuration is an ethylene fuel strip embedded in ambient air and exposed to a prescribed decaying turbulent flow field. The emphasis of this study is on the several flame extinction events observed in contrived parametric simulations. A modified viscosity and changing pressure (MVCP) scheme was adopted in order to artificially manipulate the probability of flame extinction. Using MVCP, pressure was changed from the baseline case of 1 atm to 0.1 and 10 atm. In the high pressure MVCP case, the simulated flame is extinction-free, whereas in the low pressure MVCP case, the simulated flame features frequent extinction events and is close to global extinction. Results show that, despite its relative simplicity and provided that the global flame activation temperature is correctly calibrated, the AEA-based flame extinction criterion can accurately predict the simulated flame extinction events. It is also found that the AEA-based criterion provides predictions of flame extinction that are consistent with those provided by a CEMA-based criterion. This study supports the validity of a simple Damköhler-number-based criterion to predict flame extinction in engineering-level CFD models. © 2014 The Combustion Institute.

  4. Energy analysis of stability of twin shallow tunnels based on nonlinear failure criterion

    Institute of Scientific and Technical Information of China (English)

    张佳华; 许敬叔; 张标

    2014-01-01

    Based on nonlinear Mohr−Coulomb failure criterion, the analytical solutions of stability number and supporting force on twin shallow tunnels were derived using upper bound theorem of limit analysis. The optimized solutions were obtained by the technique of sequential quadratic programming. When nonlinear coefficient equals 1 and internal friction angle equals 0, the nonlinear Mohr−Coulomb failure criterion degenerates into linear failure criterion. The calculated results of stability number in this work were compared with previous results, and the agreement verifies the effectiveness of the present method. Under the condition of nonlinear Mohr−Coulomb failure criterion, the results show that the supporting force on twin shallow tunnels obviously increases when the nonlinear coefficient, burial depth, ground load or pore water pressure coefficients increase. When the clear distance is 0.5 to 1.0 times the diameter of tunnel, the supporting force of twin shallow tunnels reaches its maximum value, which means that the tunnels are the easiest to collapse. While the clear distance increases to 3.5 times the diameter of tunnel, the calculation for twin shallow tunnels can be carried out by the method for independent single shallow tunnel. Therefore, 3.5 times the diameter of tunnel serves as a critical value to determine whether twin shallow tunnels influence each other. In designing twin shallow tunnels, appropriate clear distance value must be selected according to its change rules and actual topographic conditions, meanwhile, the influences of nonlinear failure criterion of soil materials and pore water must be completely considered. During the excavation process, supporting system should be intensified at the positions of larger burial depth or ground load to avoid collapses.

  5. Laboratory Investigation on Shear Behavior of Rock Joints and a New Peak Shear Strength Criterion

    Science.gov (United States)

    Zhang, Xiaobo; Jiang, Qinghui; Chen, Na; Wei, Wei; Feng, Xixia

    2016-09-01

    In this study, shear tests on artificial rock joints with different roughness were conducted under five normal stress levels. Test results showed that the shear strength of rock joints had a positive correlation with roughness and the applied normal stress. Observation of joint specimens after shear tests indicated that asperity damage was mainly located in the steep areas facing the shear direction. The damaged joint surfaces tend to be rough, which implies that tensile failure plays an important role in shear behavior. As a result of the anisotropic characteristic of joint roughness, two quantitative 2D roughness parameters, i.e., the revised root-mean-square of asperity angle tan-1( Z 2r) and the maximum contact coefficient C m, were proposed considering the shear direction. The proposed roughness parameters can capture the difference of roughness in forward and reverse directions along a single joint profile. The normalized tensile strength and the proposed roughness parameters were used to perform a rational derivation of peak dilatancy angle. A negative exponential-type function was found to be appropriate to model the peak dilatancy angle. Using the new model of peak dilatancy angle, we obtained a new criterion for peak shear strength of rock joints. The good agreement between test results and predicted results by the new criterion indicated that the proposed criterion is capable of estimating the peak shear strength of rock joints. Comparisons between the new criterion and published models from available literature revealed that the proposed criterion has a good accuracy for predicting the peak shear strength of joints investigated in this study.

  6. Criterion distances and environmental correlates of active commuting to school in children

    Directory of Open Access Journals (Sweden)

    D'Haese Sara

    2011-08-01

    Full Text Available Abstract Background Active commuting to school can contribute to daily physical activity levels in children. Insight into the determinants of active commuting is needed, to promote such behavior in children living within a feasible commuting distance from school. This study determined feasible distances for walking and cycling to school (criterion distances in 11- to 12-year-old Belgian children. For children living within these criterion distances from school, the correlation between parental perceptions of the environment, the number of motorized vehicles per family and the commuting mode (active/passive to school was investigated. Methods Parents (n = 696 were contacted through 44 randomly selected classes of the final year (sixth grade in elementary schools in East- and West-Flanders. Parental environmental perceptions were obtained using the parent version of Neighborhood Environment Walkability Scale for Youth (NEWS-Y. Information about active commuting to school was obtained using a self-reported questionnaire for parents. Distances from the children's home to school were objectively measured with Routenet online route planner. Criterion distances were set at the distance in which at least 85% of the active commuters lived. After the determination of these criterion distances, multilevel analyses were conducted to determine correlates of active commuting to school within these distances. Results Almost sixty percent (59.3% of the total sample commuted actively to school. Criterion distances were set at 1.5 kilometers for walking and 3.0 kilometers for cycling. In the range of 2.01 - 2.50 kilometers household distance from school, the number of passive commuters exceeded the number of active commuters. For children who were living less than 3.0 kilometers away from school, only perceived accessibility by the parents was positively associated with active commuting to school. Within the group of active commuters, a longer distance to school

  7. A BLOW-UP CRITERION FOR 3-D NON-RESISTIVE COMPRESSIBLE HEAT-CONDUCTIVE MAGNETOHYDRODYNAMIC EQUATIONS WITH INITIAL VACUUM

    Institute of Scientific and Technical Information of China (English)

    Xu Xinying

    2012-01-01

    In this paper; we prove a blow-up criterion of strong solutions to the 3-D viscous and non-resistive magnetohydrodynamic equations for compressible heat-conducting flows with initial vacuum.This blow-up criterion depends only on the gradient of velocity and the temperature,which is similar to the one for compressible Navier-Stokes equations.

  8. The D-Optimality Item Selection Criterion in the Early Stage of CAT: A Study with the Graded Response Model

    Science.gov (United States)

    Passos, Valeria Lima; Berger, Martijn P. F.; Tan, Frans E. S.

    2008-01-01

    During the early stage of computerized adaptive testing (CAT), item selection criteria based on Fisher"s information often produce less stable latent trait estimates than the Kullback-Leibler global information criterion. Robustness against early stage instability has been reported for the D-optimality criterion in a polytomous CAT with the…

  9. Multi-focus Image Fusion Using De-noising and Sharpness Criterion

    Directory of Open Access Journals (Sweden)

    sukhdip kaur

    2013-01-01

    Full Text Available the concept of multi-focus image fusion is used to combine multiple images with different objects in focus to obtain all the objects in focus and for better information in a scene. But the challenge is to how evaluate the information of the input images with better quality of image. In order to provide solution of this problem, a new criterion is proposed to give better quality of image using PCA, by de-noising and bilateral gradient based sharpness criterion that is evaluated using the gradient information of the images. Then the proposed method is further exploited to perform weighted aggregation of multi-focus images. The experimental results show that the proposed method is better than the other method in terms of quality matrices like Mutual information, spatial frequency and Average difference.

  10. An Analytical Approach to Document Clustering Based on Internal Criterion Function

    CERN Document Server

    Ranjan, Alok; Kandpal, Eatesh; Dhar, Joydip

    2010-01-01

    Fast and high quality document clustering is an important task in organizing information, search engine results obtaining from user query, enhancing web crawling and information retrieval. With the large amount of data available and with a goal of creating good quality clusters, a variety of algorithms have been developed having quality-complexity trade-offs. Among these, some algorithms seek to minimize the computational complexity using certain criterion functions which are defined for the whole set of clustering solution. In this paper, we are proposing a novel document clustering algorithm based on an internal criterion function. Most commonly used partitioning clustering algorithms (e.g. k-means) have some drawbacks as they suffer from local optimum solutions and creation of empty clusters as a clustering solution. The proposed algorithm usually does not suffer from these problems and converge to a global optimum, its performance enhances with the increase in number of clusters. We have checked our algor...

  11. Modified maximum tangential stress criterion for fracture behavior of zirconia/veneer interfaces.

    Science.gov (United States)

    Mirsayar, M M; Park, P

    2016-06-01

    The veneering porcelain sintered on zirconia is widely used in dental prostheses, but repeated mechanical loadings may cause a fracture such as edge chipping or delamination. In order to predict the crack initiation angle and fracture toughness of zirconia/veneer bi-layered components subjected to mixed mode loadings, the accuracy of a new and traditional fracture criteria are investigated. A modified maximum tangential stress criterion considering the effect of T-stress and critical distance theory is introduced, and compared to three traditional fracture criteria. Comparisons to the recently published fracture test data show that the traditional fracture criteria are not able to properly predict the fracture initiation conditions in zirconia/veneer bi-material joints. The modified maximum tangential stress criterion provides more accurate predictions of the experimental results than the traditional fracture criteria. PMID:26807673

  12. Studying the kinematic asymmetries of disks and post-coalescence mergers using a new `kinemetry' criterion

    CERN Document Server

    Bellocchi, E; Colina, L

    2012-01-01

    We have obtained VIMOS/VLT optical integral field spectroscopy (IFS) data for a sample of 4 LIRGs which have been selected at a similar distance ($\\sim$ 70 Mpc) to avoid relative resolution effects. They have been classified in two groups (isolated disk and post-coalescence mergers) according to their morphology. The $kinemetry$ method (developed by Krajnovic and coworkers) is used to characterize the kinematic properties of these galaxies and to discuss new criteria for distinguishing their status. We present and discuss new kinematic maps (i.e., velocity field and velocity dispersion) for these four galaxies. The morphological and kinematic classifications of these systems are consistent, with disks having lower kinematic asymmetries than post-coalescence mergers. We then propose and discuss a new kinematic criterion to differentiate these two groups. This criterion distinguishes better these two categories and has the advantage of being less sensitive to angular resolution effects. According to the previou...

  13. Stress-Strain Relationship and Failure Criterion for Concrete after Freezing and Thawing Cycles

    Institute of Scientific and Technical Information of China (English)

    Luo Xin; Wei Jun

    2006-01-01

    The research of the failure criterion and one-dimensional stress-strain relationship of deteriorated concrete were carried out.Based on the damage mechanics theory, the damage which reflects the alternation of internal state of material were introduced into the formula presented by Desayi and Krishman and the weighted twin-shear strength theory. As a nondestructive examination method in common use, the ultrasonic technique was adopted in the study, and the ultrasonic velocity was used to establish the damage variable. After that, the failure criterion and one-dimensional stress-strain relationship for deteriorated concrete were obtained.Eventually, tests were carried out to study the evolution laws on the damage. The results show that the more freezing and thawing cycles are, the more apparently the failure surface shrinks. Meanwhile, the comparison between theoretical data and experimental data verifies the rationality of the damage-based one-dimensional stress-strain relationship proposed.

  14. An Information-Theoretic Privacy Criterion for Query Forgery in Information Retrieval

    CERN Document Server

    Rebollo-Monedero, David; Forné, Jordi

    2011-01-01

    In previous work, we presented a novel information-theoretic privacy criterion for query forgery in the domain of information retrieval. Our criterion measured privacy risk as a divergence between the user's and the population's query distribution, and contemplated the entropy of the user's distribution as a particular case. In this work, we make a twofold contribution. First, we thoroughly interpret and justify the privacy metric proposed in our previous work, elaborating on the intimate connection between the celebrated method of entropy maximization and the use of entropies and divergences as measures of privacy. Secondly, we attempt to bridge the gap between the privacy and the information-theoretic communities by substantially adapting some technicalities of our original work to reach a wider audience, not intimately familiar with information theory and the method of types.

  15. Improved Robust Stability Criterion of Networked Control Systems with Transmission Delays and Packet Loss

    Directory of Open Access Journals (Sweden)

    Shenping Xiao

    2014-01-01

    Full Text Available The problem of stability analysis for a class of networked control systems (NCSs with network-induced delay and packet dropout is investigated in this paper. Based on the working mechanism of zero-order holder, the closed-loop NCS is modeled as a continuous-time linear system with input delay. By introducing a novel Lyapunov-Krasovskii functional which splits both the lower and upper bounds of the delay into two subintervals, respectively, and utilizes reciprocally convex combination technique, a new stability criterion is derived in terms of linear matrix inequalities. Compared with previous results in the literature, the obtained stability criterion is less conservative. Numerical examples demonstrate the validity and feasibility of the proposed method.

  16. Seismic bearing capacity of strip footings on rock masses using the Hoek–Brown failure criterion

    Directory of Open Access Journals (Sweden)

    Amin Keshavarz

    2016-04-01

    Full Text Available In this paper, the bearing capacity of strip footings on rock masses has been studied in the seismic case. The stress characteristics or slip line method was used for analysis. The problem was analyzed in the plane strain condition using the Hoek–Brown failure criterion. First, the equilibrium equations along the stress characteristics were obtained and the rock failure criterion was applied. Then, the equations were solved using the finite difference method. A computer code has been provided for analysis. Given the footing and rock parameters, the code can calculate the stress characteristics network and obtain the stress distribution under the footing. The seismic effects have been applied as the horizontal and vertical pseudo-static coefficients. The results of this paper are very close to those of the other studies. The seismic bearing capacity of weightless rock masses can be obtained using the proposed equations and graphs without calculating the whole stress characteristics network.

  17. A Rayleigh number based dendrite fragmentation criterion for detachment of solid crystals during solidification

    International Nuclear Information System (INIS)

    Movement of solid crystals in the form of dendrite fragments causes severe macro-segregation in solidified products. Dendrite fragmentation in the developing mushy zone occurs as a result of remelting (causing dissolution) and subsequent breakage of dendritic side arms from the dendritic stalks. An understanding of the mechanisms of dendrite fragmentation is essential for predicting the transport of fragmented solid crystals for possible control of macro-segregation. In this work, a Rayleigh number based fragmentation criterion is developed for detachment of dendrites from the developing mushy zone, which determines the conditions favourable for fragmentation of dendrites. The Rayleigh number, defined in this paper, measures the ratio of the driving buoyancy force for the flow in the mushy zone to the retarding frictional force associated with the permeability of the mush. The criterion developed is a function of the concentration difference, liquid fraction, permeability, growth rate of mushy layer and thermophysical properties of the material

  18. A theoretical derivation of the HoekeBrown failure criterion for rock materials

    Institute of Scientific and Technical Information of China (English)

    Jianping Zuo; Huihai Liu; Hongtao Li

    2015-01-01

    This study uses a three-dimensional crack model to theoretically derive the HoekeBrown rock failure criterion based on the linear elastic fracture theory. Specifically, we argue that a failure characteristic factor needs to exceed a critical value when macro-failure occurs. This factor is a product of the micro-failure orientation angle (characterizing the density and orientation of damaged micro-cracks) and the changing rate of the angle with respect to the major principal stress (characterizing the microscopic stability of damaged cracks). We further demonstrate that the factor mathematically leads to the empirical HoekeBrown rock failure criterion. Thus, the proposed factor is able to successfully relate the evolution of microscopic damaged crack characteristics to macro-failure. Based on this theoretical development, we also propose a quantitative relationship between the brittleeductile transition point and confining pressure, which is consistent with experimental observations.

  19. Learning image based surrogate relevance criterion for atlas selection in segmentation

    Science.gov (United States)

    Zhao, Tingting; Ruan, Dan

    2016-06-01

    Picking geometrically relevant atlases from the whole training set is crucial to multi-atlas based image segmentation, especially with extensive data of heterogeneous quality in the Big Data era. Unfortunately, there is very limited understanding of how currently used image similarity criteria reveal geometric relevance, let alone the optimization of them. This paper aims to develop a good image based surrogate relevance criterion to best reflect the underlying inaccessible geometric relevance in a learning context. We cast this surrogate learning problem into an optimization framework, by encouraging the image based surrogate to behave consistently with geometric relevance during training. In particular, we desire a criterion to be small for image pairs with similar geometry and large for those with significantly different segmentation geometry. Validation experiments on corpus callosum segmentation demonstrate the improved quality of the learned surrogate compared to benchmark surrogate candidates.

  20. Upper bound analysis of slope stability with nonlinear failure criterion based on strength reduction technique

    Institute of Scientific and Technical Information of China (English)

    ZHAO Lian-heng; LI Liang; YANG Feng; LUO Qiang; LIU Xiang

    2010-01-01

    Based on the upper bound limit analysis theorem and the shear strength reduction technique,the equation for expressing critical limit-equilibrium state was employed to define the safety factor of a given slope and its corresponding critical failure mechanism by means of the kinematical approach of limit analysis theory.The nonlinear shear strength parameters were treated as variable parameters and a kinematically admissible failure mechanism was considered for calculation schemes.The iterative optimization method was adopted to obtain the safety factors.Case study and comparative analysis show that solutions presented here agree with available predictions when nonlinear criterion reduces to linear criterion,and the validity of present method could be illuminated.From the numerical results,it can also be seen that nonlinear parameter m,slope foot gradient β,height of slope H,slope top gradient a and soil bulk density Y have significant effects on the safety factor of the slope.

  1. Criterion of cleavage crack propagation and arrest in a nuclear PWR vessel steel

    International Nuclear Information System (INIS)

    The purpose of this PhD thesis is to understand physical mechanisms of cleavage crack propagation and arrest in the 16MND5 PWR vessel steel and to propose a robust predicting model based on a brittle fracture experimental campaign of finely instrumented laboratory specimens associated with numerical computations. First, experiments were carried out on thin CT25 specimens at five temperatures (-150 C, -125 C, -100 C, -7 C, -50 C). Two kinds of crack path, straight or branching path, have been observed. To characterize crack propagation and to measure crack speed, a high-speed framing camera system was used, combined with the development of an experimental protocol which allowed to observe CT surface without icing inside the thermal chamber and on the specimen. The framing camera (520 000 fps) has allowed to have a very accurate estimation of crack speed on the complete ligament of CT (∼ 25 mm). Besides, to analyse experiments and to study the impact of viscosity on the mechanical response around the crack tip, the elastic-viscoplastic behavior of the ferritic steel has been studied up to a strain rate of 104 s-1 for the tested temperatures.The extended Finite Element Method (X-FEM) was used in CAST3M FE software to model crack propagation. Numerical computations combine a local non linear dynamic approach with a RKR type fracture stress criterion to a characteristic distance. The work carried out has confirmed the form of the criterion proposed by Prabel at -125 C, and has identified the dependencies of the criterion on temperature and strain rate. From numerical analyzes in 2D and 3D, a multi-temperature fracture stress criterion, increasing function of the strain rate, was proposed. Predictive modeling were used to confirm the identified criterion on two specimen geometries (CT and compressive ring) in mode I at different temperatures. SEM observations and 3D analyzes made with optical microscope showed that the fracture mechanism was the cleavage associated

  2. A General Criterion for Liquefaction in Granular Layers with Heterogeneous Pore Pressure

    CERN Document Server

    Goren, Liran; Aharonov, Einat; Sparks, David; Flekkøy, Eirik Grude

    2013-01-01

    Fluid-saturated granular and porous layers can undergo liquefaction and lose their shear resistance when subjected to shear forcing. In geosystems, such a process can lead to severe natural hazards of soil liquefaction, accelerating slope failure, and large earthquakes. Terzaghi's principle of effective stress predicts that liquefaction occurs when the pore pressure within the layer becomes equal to the applied normal stress on the layer. However, under dynamic loading and when the internal permeability is relatively small the pore pressure is spatially heterogeneous and it is not clear what measurement of pore pressure should be used in Terzaghi's principle. Here, we show theoretically and demonstrate using numerical simulations a general criterion for liquefaction that applies also for the cases in which the pore pressure is spatially heterogeneous. The general criterion demands that the average pore pressure along a continuous surface within the fluid-saturated granular or porous layer is equal to the appl...

  3. Suboptimal reliable guaranteed cost control for continuous-time systems with multi-criterion constraints

    Institute of Scientific and Technical Information of China (English)

    Deng-feng ZHANG; Hong-ye SU; Jian CHU; Zhi-quan WANG

    2008-01-01

    The suboptimal reliable guaranteed cost control (RGCC) with multi-criterion constraints is investigated for a class of uncertain continuous-time systems with sensor faults.A fault model in sensors,which considers outage or partial degradation of sensors,is adopted.The influence of the disturbance on the quadratic stability of the closed-loop systems is analyzed.The reliable state-feedback controller is developed by a linear matrix inequalities (LMIs) approach,to minimize the upper bound of a quadratic cost function under the conditions that all the closed-loop poles be placed in a specified disk,and that the prescribed level of H∞ disturbance attenuation and the upper bound constraints of control inputs' magnitudes be guaranteed.Thus,with the above multi-criterion constraints,the resulting closed-loop system can provide satisfactory stability,transient property,a disturbance rejection level and mininaized quadratic cost performance despite possible sensor faults.

  4. Preliminary Study to Identify Criterion for Quench Crack Prevention by Computer Simulation

    Institute of Scientific and Technical Information of China (English)

    Kyozo Arimoto; Fumiaki Ikuta; Takashi Horino; Shigeyuki Tamura; Michiharu Narazaki; Yoshio Mikita

    2004-01-01

    A criterion for preventing quench cracks has not been established although much research has been conducted in this field. A few predictions of cracking have been recently reported using simulated results of heat treatment processes.However, these results were insufficient to predict crack generation clearly because the mechanism relates not only to stress distributions in the parts but also to material characteristics. Systematic studies by the combination of experiment and simulation are therefore required to reliably identify a criterion for crack prevention by computer simulation. As a preliminary work before starting the full-scale research, a review of quench cracking research was conducted and existing test methods were classified. Several test results for cylindrical specimens were simulated for considering a cause of the crack generation. Lastly a tentative plan was made for the future research.

  5. Wavelength selection in injection-driven Hele-Shaw flows: A maximum amplitude criterion

    Science.gov (United States)

    Dias, Eduardo; Miranda, Jose

    2013-11-01

    As in most interfacial flow problems, the standard theoretical procedure to establish wavelength selection in the viscous fingering instability is to maximize the linear growth rate. However, there are important discrepancies between previous theoretical predictions and existing experimental data. In this work we perform a linear stability analysis of the radial Hele-Shaw flow system that takes into account the combined action of viscous normal stresses and wetting effects. Most importantly, we introduce an alternative selection criterion for which the selected wavelength is determined by the maximum of the interfacial perturbation amplitude. The effectiveness of such a criterion is substantiated by the significantly improved agreement between theory and experiments. We thank CNPq (Brazilian Sponsor) for financial support.

  6. Corrections to the Eckhaus' stability criterion for one-dimensional stationary structures

    Science.gov (United States)

    Malomed, B. A.; Staroselsky, I. E.; Konstantinov, A. B.

    1989-01-01

    Two amendments to the well-known Eckhaus' stability criterion for small-amplitude non-linear structures generated by weak instability of a spatially uniform state of a non-equilibrium one-dimensional system against small perturbations with finite wavelengths are obtained. Firstly, we evaluate small corrections to the main Eckhaus' term which, on the contrary so that term, do not have a universal form. Comparison of those non-universal corrections with experimental or numerical results gives a possibility to select a more relevant form of an effective nonlinear evolution equation. In particular, the comparison with such results for convective rolls and Taylor vortices gives arguments in favor of the Swift-Hohenberg equation. Secondly, we derive an analog of the Eckhaus criterion for systems degenerate in the sense that in an expansion of their non-linear parts in powers of dynamical variables, the second and third degree terms are absent.

  7. Minimum description length criterion based decision tree dynamic pruning method in speech recognition

    Institute of Scientific and Technical Information of China (English)

    XU Xianghua; HE lin

    2006-01-01

    In phonetic decision tree based state tying, decision trees with varying leaf nodes denote models with different complexity. By studying the influence of model complexity on system performance and speaker adaptation, a decision tree dynamic pruning method based on Minimum Description Length (MDL) criterion is presented. In the method, a well-trained,large-sized phonetic decision tree is selected as an initial model set, and model complexity is computed by adding a penalty parameter which alters according to the amount of adaptation data. Largely attributed to the reasonable selection of initial models and the integration of stochastic and aptotic of MDL criterion, the proposed method gains high performance by combining with speaker adaptation.

  8. Ethical leadership: meta-analytic evidence of criterion-related and incremental validity.

    Science.gov (United States)

    Ng, Thomas W H; Feldman, Daniel C

    2015-05-01

    This study examines the criterion-related and incremental validity of ethical leadership (EL) with meta-analytic data. Across 101 samples published over the last 15 years (N = 29,620), we observed that EL demonstrated acceptable criterion-related validity with variables that tap followers' job attitudes, job performance, and evaluations of their leaders. Further, followers' trust in the leader mediated the relationships of EL with job attitudes and performance. In terms of incremental validity, we found that EL significantly, albeit weakly in some cases, predicted task performance, citizenship behavior, and counterproductive work behavior-even after controlling for the effects of such variables as transformational leadership, use of contingent rewards, management by exception, interactional fairness, and destructive leadership. The article concludes with a discussion of ways to strengthen the incremental validity of EL. (PsycINFO Database Record PMID:25420055

  9. A New Ductile Fracture Criterion for Various Deformation Conditions Based on Microvoid Model

    Institute of Scientific and Technical Information of China (English)

    HUANG Jian-ke; DONG Xiang-huai

    2009-01-01

    To accurately predict the occurrence of ductile fracture in metal forming processes, the Gurson-Tvergaard (GT) porous material model with optimized adjustment parameters is adopted to analyze the macroscopic stress-strain response, and a practical void nucleation law is proposed with a few material constants for engineering applications. Mechanical and metallographie analyses of uniaxial tension, torsion and upsetting experiments are performed. According to the character of the metal forming processes, the basic mechanisms of ductile fracture are divided into two modes: tension-type mode and shear-type mode. A unified fracture criterion is proposed for wide applicable range, and the comparison of experimental results with numerical analysis results confirms the validity of the newly proposed ductile fracture criterion based on the GT porous material model.

  10. Strength criterion for rocks under compressive-tensile stresses and its application

    Directory of Open Access Journals (Sweden)

    Mingqing You

    2015-08-01

    Full Text Available Estimating in-situ stress with hydraulic borehole fracturing involves tensile strength of rock. Several strength criteria with three parameters result in tensile strengths with great differences, although they may describe the relation between strength of rock and confining pressure with low misfits. The exponential criterion provides acceptable magnitudes of tensile strengths for granites and over-estimates that for other rocks, but the criterion with tension cut-off is applicable to all rocks. The breakdown pressure will be lower than the shut-in pressure during hydraulic borehole fracturing, when the maximum horizontal principal stress is 2 times larger than the minor one; and it is not the peak value in the first cycle, but the point where the slope of pressure-time curve begins to decline.

  11. Fracture criterion for predicting surface cracking of Ti40 alloy in hot forming processes

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xue-min; ZENG Wei-dong; SHU Ying; ZHOU Yi-gang; ZHAO Yong-qing; WU Huan; YU Han-qing

    2009-01-01

    Hot compression tests were conducted on Ti40 burn resistant titanium alloy in the temperature range of 900-1 100 ℃ and strain rate range of 0.01-10 s-1 to investigate its fracture behavior and critical fracture conditions in hot forming. It was observed that the failure of Ti40 alloy is attributed to longitudinal surface cracking due to severe oxidation of element V and the secondary tensile stresses. The critical fracture strain increases with increasing temperature and decreasing strain rate. From these observations and parallel FEM simulations, it was concluded that the critical fracture strain is a function of a single argument Zener-Hollomon parameter, and there is a linear relationship between them. An Oyane criterion successfully predicted the location of crack initiation. The critical fracture values also exhibit a liner relationship with lnZ. Based on these results, a new fracture criterion of Ti40 alloy based on Zener-Hollomon parameter was established.

  12. MARSHALLIAN DEVIATION:NEW OBSERVABLE CRITERION TO MEASURE TRANSACTION PATHS IN DOUBLE AUCTION MARKETS

    Institute of Scientific and Technical Information of China (English)

    ZHANWenjie; WANGShouyang; 等

    2002-01-01

    In measuring the trade process in a double anction(DA) market,there is not any observable criterion that is able to describe the matching pairs and their transaction order dynamically,In this paper,we propse a new observable criterion called Marshallian deviation.It can be used to measure the distance of a transaction path deviating from the Marshallian path mathematically,and to answer the question why buyers with high values will trade with sellers with low costs in advance in some types of DA but not in others.Furthermore,three factors influencing the Marshallian deviations both in the CDA and in the PDA are also studied.They are repectively the strategic algorithm,the transaction duration and the number of traders.A few intersting findings are presented.

  13. The Instability Transition for the Restricted 3-Body Problem. III. The Lyapunov Exponent Criterion

    CERN Document Server

    Quarles, B; Musielak, Z E; Cuntz, M

    2011-01-01

    We establish a criterion for the stability of planetary orbits in stellar binary systems by using Lyapunov exponents and power spectra for the special case of the circular restricted 3-body problem (CR3BP). The centerpiece of our method is the concept of Lyapunov exponents, which are incorporated into the analysis of orbital stability by integrating the Jacobian of the CR3BP and orthogonalizing the tangent vectors via a well-established algorithm originally developed by Wolf et al. The criterion for orbital stability based on the Lyapunov exponents is independently verified by using power spectra. The obtained results are compared to results presented in the two previous papers of this series. It is shown that the maximum Lyapunov exponent can be used as an indicator for chaotic behaviour of planetary orbits, which is consistent with previous applications of this method, particularly studies for the Solar System. The chaotic behaviour corresponds to either orbital stability or instability, and it depends sole...

  14. A theoretical derivation of the Hoek–Brown failure criterion for rock materials

    Directory of Open Access Journals (Sweden)

    Jianping Zuo

    2015-08-01

    Full Text Available This study uses a three-dimensional crack model to theoretically derive the Hoek–Brown rock failure criterion based on the linear elastic fracture theory. Specifically, we argue that a failure characteristic factor needs to exceed a critical value when macro-failure occurs. This factor is a product of the micro-failure orientation angle (characterizing the density and orientation of damaged micro-cracks and the changing rate of the angle with respect to the major principal stress (characterizing the microscopic stability of damaged cracks. We further demonstrate that the factor mathematically leads to the empirical Hoek–Brown rock failure criterion. Thus, the proposed factor is able to successfully relate the evolution of microscopic damaged crack characteristics to macro-failure. Based on this theoretical development, we also propose a quantitative relationship between the brittle–ductile transition point and confining pressure, which is consistent with experimental observations.

  15. Metropolis Criterion Based Fuzzy Q-Learning Energy Management for Smart Grids

    Directory of Open Access Journals (Sweden)

    Haibin Yu

    2012-12-01

    Full Text Available For the energy management problems for demand response in electricity grid, a Metropolis Criterion based fuzzy Q-learning consumer energy management controller (CEMC is proposed. Because of the uncertainties and highly time-varying, it is not easy to accurately obtain the complete information for the consumer behavior in electricity grid. In this case, the Q-learning, which is independent of mathematic model, and prior-knowledge, has good performance. The fuzzy inference and Metropolis Criterion are introduced in order to facilitate generalization in large state space and balance exploration and exploitation in action selection in Q-learning individually. Simulation results show that the proposed controller can learn to take the best action to regulate consumer behavior with the features of low average end-user financial costs and high consumer satisfaction.

  16. A criterion for the onset of slugging in horizontal stratified air-water countercurrent flow

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Moon-Hyun; Lee, Byung-Ryung; Kim, Yang-Seok [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)] [and others

    1995-09-01

    This paper presents an experimental and theoretical investigation of wave height and transition criterion from wavy to slug flow in horizontal air-water countercurrent stratified flow conditions. A theoretical formula for the wave height in a stratified wavy flow regime has been developed using the concept of total energy balance over a wave crest to consider the shear stress acting on the interface of two fluids. From the limiting condition of the formula for the wave height, a necessary criterion for transition from a stratified wavy flow to a slug flow has been derived. A series of experiments have been conducted changing the non-dimensional water depth and the flow rates of air in a horizontal pipe and a duct. Comparisons between the measured data and the predictions of the present theory show that the agreement is within {plus_minus}8%.

  17. 3D homogenised strength criterion for masonry: Application to drystone retaining walls

    Science.gov (United States)

    Le, Hong Hanh; Garnier, Denis; Colas, Anne-Sophie; Terrade, Benjamin; Morel, Jean-Claude

    2016-10-01

    A 3D strength criterion for masonry is constructed based on yield design theory. Yield design homogenisation provides a rigorous theoretical framework to determine the yield strength properties of a periodic medium, based on the properties of its constituent materials. First, theoretical basis of 2D homogenisation of periodic media, and more particularly its application in the framework of yield design, will be retrieved. Then, 2D principles are extended to exhibit a 3D domain of running-bond masonry. This criterion is finally used to assess the stability of a drystone retaining wall loaded by an axle load, and theoretical results are compared to experimental data. Perspectives on this work are given as a conclusion.

  18. Runaway Criterion in Fixed Bed Catalytic Reactors with Radial Temperature Profile

    Institute of Scientific and Technical Information of China (English)

    吴鹏; 樊勇; 李绍芬

    1999-01-01

    The discrepancy between pseudo-homogeneous one-dimensional model and peeudo-homogeneous two-dimensional model is studied. It is found that there are great differences between two models. This paper compares the maximum and minimum values of the radial temperature in the hot spot in came that a single exothermic reaction is carried out, a correlation is obtlioed with peeudo-homogeneous one-dimensional model to describe the entire reactor behavier. A new runaway criterion, based on the occurrence of inflection in the hot spot locus, is developed for the case of pseudo-homogeneous two-dimensional model. This criterion predicts the maximum allowable temperature for safe operation and the regions of runaway, respectively. The calculated results show that, compared with the results based on pseudo-homogeneous one-dimensional model, runaway will easily occur when the radial temperature gradient has to be considered.

  19. Three-Dimensional Analysis of Rolling by Twin Shear Stress Yield Criterion

    Institute of Scientific and Technical Information of China (English)

    ZHAO De-wen; XIE Ying-jie; LIU Xiang-hua; WANG Guo-dong

    2006-01-01

    Using the twin shear stress yield criterion, the surface integral of the co-line vectors, and the integration depending on upper limit, Kobayashi's three-dimensional velocity field of rolling was analyzed and an analytical expression of rolling torque and single force was obtained. Through redoing the same experiment of rolling pure lead as Sims, the calculated results by the above expression were compared with those of Kobayashi and Sims formulae. The results show that the twin shear stress yield criterion is available for rolling analysis and the calculated results by the new formula are a little higher than those by Kobayashi and Sims ones if the reduction ratio is less than 30%.

  20. Focused information criterion and model averaging based on weighted composite quantile regression

    KAUST Repository

    Xu, Ganggang

    2013-08-13

    We study the focused information criterion and frequentist model averaging and their application to post-model-selection inference for weighted composite quantile regression (WCQR) in the context of the additive partial linear models. With the non-parametric functions approximated by polynomial splines, we show that, under certain conditions, the asymptotic distribution of the frequentist model averaging WCQR-estimator of a focused parameter is a non-linear mixture of normal distributions. This asymptotic distribution is used to construct confidence intervals that achieve the nominal coverage probability. With properly chosen weights, the focused information criterion based WCQR estimators are not only robust to outliers and non-normal residuals but also can achieve efficiency close to the maximum likelihood estimator, without assuming the true error distribution. Simulation studies and a real data analysis are used to illustrate the effectiveness of the proposed procedure. © 2013 Board of the Foundation of the Scandinavian Journal of Statistics..

  1. LOGARITHMICALLY IMPROVED REGULARITY CRITERION FOR THE 3D GENERALIZED MAGNETO-HYDRODYNAMIC EQUATIONS

    Institute of Scientific and Technical Information of China (English)

    赵继红; 刘桥

    2014-01-01

    This article proves the logarithmically improved Serrin’s criterion for solutions of the 3D generalized magneto-hydrodynamic equations in terms of the gradient of the velocity field, which can be regarded as improvement of results in [10] (Luo Y W. On the regularity of generalized MHD equations. J Math Anal Appl, 2010, 365: 806-808) and [18] (Zhang Z J. Remarks on the regularity criteria for generalized MHD equations. J Math Anal Appl, 2011, 375: 799-802).

  2. Application of a criterion for cold cracking to casting high strength aluminum alloys

    OpenAIRE

    Lalpoor, M; Eskin, D G; Fjaer, H.G.; Ten Cate, A.; Ontijt, N.; Katgerman, L.

    2010-01-01

    Direct chill (DC) casting of high strength 7xxx series aluminium alloys is difficult mainly due to solidification cracking (hot cracks) and solid state cracking (cold cracks). Poor thermal properties along with extreme brittleness in the as-cast condition make DC-casting of such alloys a challenging process. Therefore, a criterion that can predict the catastrophic failure and cold cracking of the ingots would be highly beneficial to the aluminium industry. The already established criteria are...

  3. An integral criterion for appraising the overall quality of a computer-based hydroturbine governing system

    Energy Technology Data Exchange (ETDEWEB)

    Ye Luqing; Li Weidong; Li Zhaohui [Huazhong Univ. of Science and Technology, Wuhan, Hubei (China). Dept. of Electrical Engineering; Malik, O.P.; Hope, G.S. [Univ. of Calgary, Alberta (Canada). Dept. of Electrical Engineering

    1995-06-01

    In this paper, an integral criterion is developed for overall analysis and appraisal of the performance, reliability and economy of a computer-based control system. A concept of performability is discussed, and the economic optimality is based on the overall benefits from the manufacturer to the user. A case study for a hydroturbine governing system is given. A comparison between different system configurations shows that it is helpful and beneficial to select a system possessing high indices and excellent quality.

  4. Examination of a micromechanics based failure criterion for non-crimp fiber reinforced composite laminates

    OpenAIRE

    Fırlar, Emre; Firlar, Emre

    2008-01-01

    Warp-knit non-crimp fabric (NCF) reinforced polymer matrix composites manufactured by vacuum infusion (VI) have become appealing for structural applications, particularly in automotive parts, wind turbine blade production and marine industry. Their efficient and optimal use in structural design relies on the accuracy of the selected failure criterion typically specific to fiber reinforced composites. Experimental studies are conducted in order to measure the accuracy of the methodology of the...

  5. A termination criterion for parameter estimation in stochastic models in systems biology.

    Science.gov (United States)

    Zimmer, Christoph; Sahle, Sven

    2015-11-01

    Parameter estimation procedures are a central aspect of modeling approaches in systems biology. They are often computationally expensive, especially when the models take stochasticity into account. Typically parameter estimation involves the iterative optimization of an objective function that describes how well the model fits some measured data with a certain set of parameter values. In order to limit the computational expenses it is therefore important to apply an adequate stopping criterion for the optimization process, so that the optimization continues at least until a reasonable fit is obtained, but not much longer. In the case of stochastic modeling, at least some parameter estimation schemes involve an objective function that is itself a random variable. This means that plain convergence tests are not a priori suitable as stopping criteria. This article suggests a termination criterion suited to optimization problems in parameter estimation arising from stochastic models in systems biology. The termination criterion is developed for optimization algorithms that involve populations of parameter sets, such as particle swarm or evolutionary algorithms. It is based on comparing the variance of the objective function over the whole population of parameter sets with the variance of repeated evaluations of the objective function at the best parameter set. The performance is demonstrated for several different algorithms. To test the termination criterion we choose polynomial test functions as well as systems biology models such as an Immigration-Death model and a bistable genetic toggle switch. The genetic toggle switch is an especially challenging test case as it shows a stochastic switching between two steady states which is qualitatively different from the model behavior in a deterministic model.

  6. An optimization method for approximating the macroscopic strength criterion of stone column reinforced soils

    OpenAIRE

    Gueguin, Maxime; Hassen, Ghazi; Bleyer, Jérémy; De Buhan, Patrick

    2013-01-01

    International audience In this contribution, the yield design homogenization method is applied to the evaluation of the ultimate bearing capacity of a purely cohesive soil reinforced by a periodic array of columnar inclusions, made of a purely frictional material (stone column technique). The method is implemented following a three-step procedure. a) First, the numerical determination of the macroscopic strength criterion is performed using the kinematic approach of yield design. b) Second...

  7. Viability decision of linear discrete-time stochastic systems with probability criterion

    Institute of Scientific and Technical Information of China (English)

    Wansheng TANG; Jun ZHENG; Jianxiong ZHANG

    2009-01-01

    In this paper,the optimal viability decision problem of linear discrete-time stochastic systems with probability criterion is investigated.Under the condition of sequence-reachable discrete-time dynamic systems,the existence theorem of optimal viability strategy is given and the solving procedure of the optimal strategy is provided based on dynamic programming.A numerical example shows the effectiveness of the proposed methods.

  8. Algorithm and criterion of quality for assessing the packing of polymer microspheres

    Science.gov (United States)

    Kozlov, A. A.; Abdullaev, S. D.; Flid, V. R.; Gusev, S. A.

    2016-09-01

    An algorithm for assessing the quality of the packing of two-dimensional ordered structures, prepared using polymer microspheres 20 μm in diameter on a water surface, is proposed. An analysis is performed on the basis of optical microscopy images. The area of the largest ordered microsphere domain in an image is used as the quality criterion. The algorithm simplifies analysis of the ordered structures.

  9. An Anisotropic Partial Regularity Criterion for the Navier-Stokes Equations

    Science.gov (United States)

    Kukavica, Igor; Rusin, Walter; Ziane, Mohammed

    2016-07-01

    In this paper, we address the partial regularity of suitable weak solutions of the incompressible Navier-Stokes equations. We prove an interior regularity criterion involving only one component of the velocity. Namely, if (u, p) is a suitable weak solution and a certain scale-invariant quantity involving only u 3 is small on a space-time cylinder {{Qr^{*}}(x_0,t_0)} , then u is regular at (x 0, t 0).

  10. h-Adaptive Mesh Generation using Electric Field Intensity Value as a Criterion (in Japanese)

    OpenAIRE

    Toyonaga, Kiyomi; Cingoski, Vlatko; Kaneda, Kazufumi; Yamashita, Hideo

    1994-01-01

    Finite mesh divisions are essential to obtain accurate solution of two dimensional electric field analysis. It requires the technical knowledge to generate a suitable fine mesh divisions. In electric field problem, analysts are usually interested in the electric field intensity and its distribution. In order to obtain electric field intensity with high-accuracy, we have developed and adaptive mesh generator using electric field intensity value as a criterion.

  11. Non-Standard Rates of Convergence of Criterion-Function-Based Set Estimators

    OpenAIRE

    Jason R. Blevins

    2013-01-01

    This paper establishes conditions for consistency and potentially non-standard rates of convergence for set estimators based on contour sets of criterion functions. These conditions cover the standard parametric rate $n^{-1/2}$, non-standard polynomial rates such as $n^{-1/3}$, and an extreme case of arbitrarily fast convergence. We also establish the validity of a subsampling procedure for constructing confidence sets for the identified set. We then provide more convenient sufficient conditi...

  12. Partial dynamical symmetry as a selection criterion for many-body interactions

    CERN Document Server

    Leviatan, A; Van Isacker, P

    2013-01-01

    We propose the use of partial dynamical symmetry (PDS) as a selection criterion for higher-order terms in situations when a prescribed symmetry is obeyed by some states and is strongly broken in others. The procedure is demonstrated in a first systematic classification of many-body interactions with SU(3) PDS that can improve the description of deformed nuclei. As an example, the triaxial features of the nucleus 156Gd are analyzed.

  13. Optimal Base Wavelet Selection for ECG Noise Reduction Using a Comprehensive Entropy Criterion

    OpenAIRE

    Hong He; Yonghong Tan; Yuexia Wang

    2015-01-01

    The selection of an appropriate wavelet is an essential issue that should be addressed in the wavelet-based filtering of electrocardiogram (ECG) signals. Since entropy can measure the features of uncertainty associated with the ECG signal, a novel comprehensive entropy criterion Ecom based on multiple criteria related to entropy and energy is proposed in this paper to search for an optimal base wavelet for a specific ECG signal. Taking account of the decomposition capability of wavelets and t...

  14. Estimation of the enterprise marketing activity by criterion on future abilities creation to form demand

    OpenAIRE

    L.V. Potrashkova

    2015-01-01

    The aim of the article. The aim of the article is to develop theoretic grounds to calculate enterprise marketing activity factors, which characterize its long term consequences with production demand formation in future. The results of the analysis. One suggests to estimate enterprise marketing activity by criterion on future enterprise abilities creation to form production demand. That’s why enterprise marketing activity factors have to include enterprise marketing potential factors. Thes...

  15. Distortion as a validation criterion in the identification of suspicious reviews

    OpenAIRE

    Wu, Guangyu; Greene, Derek; Smyth, Barry; Cunningham, Pádraig

    2010-01-01

    Assessing the trustworthiness of reviews is a key issue for the maintainers of opinion sites such as TripAdvisor. In this paper we propose a distortion criterion for assessing the impact of methods for uncovering suspicious hotel reviews in TripAdvisor. The principle is that dishonest reviews will distort the overall popularity ranking for a collection of hotels. Thus a mechanism that deletes dishonest reviews will distort the popularity ranking significantly, when compar...

  16. Criterion of Quantum Entanglement and the Covariance Correlation Tensor in the Theory of Quantum Network

    Institute of Scientific and Technical Information of China (English)

    QIAN Shang-Wu; GU Zhi-Yu

    2003-01-01

    This article discusses the covariance correlation tensor (CCT) in quantum network theory for four Bell bases in detail. Furthermore, it gives the expression of the density operator in terms of CCT for a quantum network of three nodes, thus gives the criterion of entanglement for this case, i.e. the conditions of complete separability and partial separability for a given quantum state of three bodies. Finally it discusses the general case for the quantum network of m≥3 nodes.

  17. Regular Reflection in Self-Similar Potential Flow and the Sonic Criterion

    OpenAIRE

    Elling, Volker

    2010-01-01

    Reflection of a shock from a solid wedge is a classical problem in gas dynamics. Depending on the parameters either a regular or a irregular (Mach-type) reflection results. We construct regular reflection as an exact self-similar solution for potential flow. For some upstream Mach numbers $M_I$ and isentropic coefficients $\\gamma$, a solution exists for all wedge angles $\\theta$ allowed by the sonic criterion. This demonstrates that, at least for potential flow, weaker crite...

  18. The Development, Validation and Application of an External Criterion Measure of Achievement Test Item Bias.

    Science.gov (United States)

    Harms, Robert A.

    Based on John Rawls' theory of justice as fairness, a nine-item rating scale was developed to serve as a criterion in studies of test item bias. Two principles underlie the scale: (1) Within a defined usage, test items should not affect students so that they are unable to do as well as their abilities would indicate; and (2) within the domain of a…

  19. On a Criterion for Simultaneous Block-Diagonalization of Normal Matrices

    Science.gov (United States)

    Pastuszak, G.; Kamizawa, T.; Jamiołkowski, A.

    2016-03-01

    Assume that A1, … , As are complex normal n × n matrices, p is a natural number and S2p is the standard polynomial in 2p non-commutative variables. It follows from classical results of S. Amitsur, J. Levitzki and H. Shapiro that A1, … , As can be simultaneously block-diagonalized by a unitary matrix with blocks of sizes not greater than p if and only if the algebra generated by A1, … , As satisfies the polynomial identity S2p = 0. We call this theorem the ALS-criterion for simultaneous block-diagonalization of normal matrices. In this paper, we present some application of the ALS-criterion in quantum theory. Namely, we give another proof of the renowned Morris-Shore transformation. Moreover, we discuss computable versions of the ALS-criterion. These versions allow one to verify the condition S2p = 0 in a finite number of steps. Such an approach is more useful in practical applications than the original one.

  20. Elastic-plastic strain acceptance criterion for structures subject to rapidly applied transient dynamic loading

    Energy Technology Data Exchange (ETDEWEB)

    Solonick, W. [Electric Boat Corp., Groton, CT (United States)

    1996-11-01

    Rapidly applied transient dynamic loads produce stresses and deflections in structures that typically exceed those from static loading conditions. Previous acceptance criteria for structures designed for rapidly applied transient dynamic loading limited stresses to those determined from elastic analysis. Different stress limits were established for different grades of structure depending upon the amount of permanent set considered acceptable. Structure allowed to sustain very limited permanent set is designed to stress limits not significantly greater than yield stress. Greater permanent set in structure under rapidly applied transient dynamic loading conditions is permitted by establishing stress limits that are significantly greater than yield stress but still provide adequate safety margin (with respect to failure). This paper presents a strain-based elastic-plastic (i.e., inelastic) analysis criterion developed as an alternative to the more conservative stress-based elastic analysis stress criterion for structures subjected to rapidly applied transient dynamic loading. The strain limits established are based on a fraction of the strain at ultimate stress obtained from an engineering stress/strain curve of the material. Strains limits are categorized by type as membrane or surface and by region as general, local, or concentrated. The application of the elastic-plastic criterion provides a more accurate, less conservative design/analysis basis for structures than that used in elastic stress-based analysis criteria, while still providing adequate safety margins.

  1. The universal criterion for switching a magnetic vortex core in soft magnetic nanodots

    Energy Technology Data Exchange (ETDEWEB)

    Lee, K.-S.; Kim, S.-K.; Yu, Y.-S.; Choi, Y.-S.; Guslienko, K. Y.; Jung, H.; Fischer, P.

    2008-10-01

    The universal criterion for ultrafast vortex core switching between core-up and -down vortex bi-states in soft magnetic nanodots was empirically investigated by micromagnetic simulations and combined with an analytical approach. Vortex-core switching occurs whenever the velocity of vortex core motion reaches a critical value, which is {nu}{sub c} = 330 {+-} 37 m/s for Permalloy, as estimated from numerical simulations. This critical velocity was found to be {nu}{sub c} = {eta}{sub c}{gamma} {radical}A{sub ex} with A{sub ex} the exchange stiffness, {gamma} the gyromagnetic ratio, and an estimated proportional constant {eta}{sub c} = 1.66 {+-} 0.18. This criterion does neither depend on driving force parameters nor on the dimension or geometry of the magnetic specimen. The phase diagrams for the vortex core switching criterion and its switching time with respect to both the strength and angular frequency of circular rotating magnetic fields were derived, which offer practical guidance for implementing vortex core switching into future solid state information storage devices.

  2. The criterion for time symmetry of probabilistic theories and the reversibility of quantum mechanics

    International Nuclear Information System (INIS)

    Physicists routinely claim that the fundamental laws of physics are 'time symmetric' or 'time reversal invariant' or 'reversible'. In particular, it is claimed that the theory of quantum mechanics is time symmetric. But it is shown in this paper that the orthodox analysis suffers from a fatal conceptual error, because the logical criterion for judging the time symmetry of probabilistic theories has been incorrectly formulated. The correct criterion requires symmetry between future-directed laws and past-directed laws. This criterion is formulated and proved in detail. The orthodox claim that quantum mechanics is reversible is re-evaluated. The property demonstrated in the orthodox analysis is shown to be quite distinct from time reversal invariance. The view of Satosi Watanabe that quantum mechanics is time asymmetric is verified, as well as his view that this feature does not merely show a de facto or 'contingent' asymmetry, as commonly supposed, but implies a genuine failure of time reversal invariance of the laws of quantum mechanics. The laws of quantum mechanics would be incompatible with a time-reversed version of our universe

  3. New Quality Assessment Criterion of AlSi5Cu1 Alloy

    Directory of Open Access Journals (Sweden)

    M. Wierzbińska

    2007-07-01

    Full Text Available The paper presents the discussion of the results of mechanical testing for aluminium foundry alloy AlSi5Cu1Mg for high-loaded machine elements. Values of yield strength (Rp0.2, tensile strength (Rm, elongation(A5 and hardness (HB are usually considered as the primary quality assessment criterion for a manufacturing process. It was concluded, that this criterion, A5 index particularly, is unsatisfactory to estimate the plasticity of the alloy and its crack resistance in the presence of sharp-pointed stress concentrators or microcracks. More adequate parameter is plane strain fracture toughness KIc. However, size of the samples appeared to be twice as large as would be needed to fulfill requirements of test conditions, and the test itself is laborious and time-consuming that it becomes impractical as a acceptance test. Therefore, substitute test for quality assessment – determination of tensile strength in the presence of a sharp notch kmR was applied. The comparative analysis of kmR/Rp0.2 ratio, as a more enhanced fatigue resistance criterion than kmR and plane strain fracture toughness KIc of the alloy was performed. It was assumed that kmR/Rp0.2 parameter has good correlation with the critical stress intensity factor KIc Thus, under manufacturing process conditions, being unable to carry out KIc test, it may be successfully replaced by kmR test.

  4. Activity criterion of pre-existing fabrics in non-homogeneous deformation domain

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The Anderson’s model can be applied only to elastic homogeneous deformation and cannot explain complicated phenomena of natural faults, which to a large degree limits the model to practical application. By combing the Coulomb-Mohr Criterion with the sandbox modeling and considering non-homogeneous deformation, mechanisms of how basement pre-existing fabrics control fault formation and evolution are analyzed and a mechanical factor, activation-coefficient (faS) of pre-existing fabrics, is proposed. It is determined by the attitude and mechanical properties of pre-existing fabric, and the stress state (the magnitudes and directions of the three principal stresses). The coefficient has taken the heterogeneity of rocks into account and may serve as a criterion for evaluating the activity of a pre-existing fabric. The Mohr-Coulomb Criterion is expanded to non-homogeneous deformation domain in terms of activation-coefficient (faS) of pre-existing fabrics, the general law of the activity of a pre-existing fabric is predicted, the fault complexity real of rift basin is revealed in theory, and the controlling law of basement pre-existing faults to fault formation and evolution is determined, and checked with sandbox modeling. A new way is provided for in-depth study of faulting.

  5. Scale-up criterion of power consumption for a surface aerator used in wastewater treatment tank

    Directory of Open Access Journals (Sweden)

    Hayder M. Issa

    2016-01-01

    Full Text Available The major part of operation costs in surface aeration basins or tanks is because of power requirements. Therefore, it is always necessary to find a dependable criterion for the predictive scale-up of power consumption measurements obtained at laboratory-scale surface aeration tanks to industrial-scale wastewater treatment surface aeration systems. A scale-up approach was proposed in this work for volumetric power consumption between geometrically similar laboratory-scale and industrial full-scale surface aeration tanks at an invariant Froude number Fr. Scale-up order between the laboratory and industrial sizes was 7.4. A mathematical correlation has been developed to estimate the volumetric power consumption and then compared with a model that already was investigated experimentally. Scale-up criterion involved the evaluation of three similarities; the geometrical, kinematic and dynamics. The scale-up basis that developed in this work led us to achieve a suitable scale-up criterion for volumetric power consumption in aeration tanks at matched surface flow condition. At matched Froude number Fr for the laboratory and industrial scales and at low and moderate turbine rotation speeds for surface aeration than 0.8 rps, complete predictions of volumetric power consumption have been achieved. The prediction by the existing previous model showed higher results than the actual values.

  6. Improvement of Image Matching by using the Proximity Criterion: Application to Omnidirectional and Perspective Images

    Directory of Open Access Journals (Sweden)

    Ibrahim Guelzim

    2011-01-01

    Full Text Available Problem statement: In computer vision, matching is an important phase for several applications (object reconstruction, robot navigation .... The similarity measures used provided results which could be improved. Approach: This research proposed to improve image matching by using the proximity criterion. The similarity measures used mutual information and correlation coefficient. The matching was done between neighborhoods of points of interest extracted from the images. The second chance algorithm was also applied. We have worked in case which the sensor had a slight displacement between two images. The tests were performed on omnidirectional and perspective grayscale images. Results: The improvement by introducing the proximity criterion reached 15.9% for non-noised perspective images, 32.1% for noised perspective images, 47.69% for non-noised omnidirectional images and 58.5% for noised omnidirectional images. Conclusion/Recommendations: The introduction of the proximity criterion has significantly improved the performance of the matching. The method is recommended in mobile robotics, knowing that a good matching leads to a better location and better movement of the robot.

  7. Criterion for the integrality of the Taylor coefficients of mirror maps in several variables

    CERN Document Server

    Delaygue, Eric

    2011-01-01

    We give a necessary and sufficient condition for the integrality of the Taylor coefficients at the origin of formal power series $q_i({\\mathbf z})=z_i\\exp(G_i({\\mathbf z})/F({\\mathbf z}))$, with ${\\mathbf z}=(z_1,...,z_d)$ and where $F({\\mathbf z})$ and $G_i({\\mathbf z})+\\log(z_i)F({\\mathbf z})$, $i=1,...,d$ are particular solutions of certain A-systems of differential equations. This criterion is based on the analytical properties of Landau's function (which is classically associated with the sequences of factorial ratios) and it generalizes the criterion in the case of one variable presented in "Crit\\`ere pour l'int\\'egralit\\'e des coefficients de Taylor des applications miroir" [J. Reine Angew. Math.]. One of the techniques used to prove this criterion is a generalization of a version of a theorem of Dwork on the formal congruences between formal series, proved by Krattenthaler and Rivoal in "Multivariate $p$-adic formal congruences and integrality of Taylor coefficients of mirror maps" [arXiv:0804.3049v3,...

  8. The criterion for time symmetry of probabilistic theories and the reversibility of quantum mechanics

    Science.gov (United States)

    Holster, A. T.

    2003-10-01

    Physicists routinely claim that the fundamental laws of physics are 'time symmetric' or 'time reversal invariant' or 'reversible'. In particular, it is claimed that the theory of quantum mechanics is time symmetric. But it is shown in this paper that the orthodox analysis suffers from a fatal conceptual error, because the logical criterion for judging the time symmetry of probabilistic theories has been incorrectly formulated. The correct criterion requires symmetry between future-directed laws and past-directed laws. This criterion is formulated and proved in detail. The orthodox claim that quantum mechanics is reversible is re-evaluated. The property demonstrated in the orthodox analysis is shown to be quite distinct from time reversal invariance. The view of Satosi Watanabe that quantum mechanics is time asymmetric is verified, as well as his view that this feature does not merely show a de facto or 'contingent' asymmetry, as commonly supposed, but implies a genuine failure of time reversal invariance of the laws of quantum mechanics. The laws of quantum mechanics would be incompatible with a time-reversed version of our universe.

  9. Formulating robust linear regression estimation as a one-class LDA criterion: discriminative hat matrix.

    Science.gov (United States)

    Dufrenois, F; Noyer, J C

    2013-02-01

    Linear discriminant analysis, such as Fisher's criterion, is a statistical learning tool traditionally devoted to separating a training dataset into two or even several classes by the way of linear decision boundaries. In this paper, we show that this tool can formalize the robust linear regression problem as a robust estimator will do. More precisely, we develop a one-class Fischer's criterion in which the maximization provides both the regression parameters and the separation of the data in two classes: typical data and atypical data or outliers. This new criterion is built on the statistical properties of the subspace decomposition of the hat matrix. From this angle, we improve the discriminative properties of the hat matrix which is traditionally used as outlier diagnostic measure in linear regression. Naturally, we call this new approach discriminative hat matrix. The proposed algorithm is fully nonsupervised and needs only the initialization of one parameter. Synthetic and real datasets are used to study the performance both in terms of regression and classification of the proposed approach. We also illustrate its potential application to image recognition and fundamental matrix estimation in computer vision.

  10. ON THE COMPARISON OF BAYESIAN INFORMATION CRITERION AND DRAPER'S INFORMATION CRITERION IN SELECTION OF AN ASYMMETRIC PRICE RELATIONSHIP: BOOTSTRAP SIMULATION RESULTS

    Directory of Open Access Journals (Sweden)

    Henry de-Graft Acquah

    2013-03-01

    Full Text Available Alternative formulations of the Bayesian Information Criteria provide a basis for choosing between competing methods for detecting price asymmetry. However, very little is understood about their performance in the asymmetric price transmission modelling framework. In addressing this issue, this paper introduces and applies parametric bootstrap techniques to evaluate the ability of Bayesian Information Criteria (BIC and Draper's Information Criteria (DIC in discriminating between alternative asymmetric price transmission models under various error and sample size conditions. The results of the bootstrap simulations indicate that model selection performance depends on bootstrap sample size and the amount of noise in the data generating process. The Bayesian criterion clearly identifies the true asymmetric model out of different competing models in the presence of bootstrap samples. Draper's Information Criteria (DIC; Draper, 1995 outperforms BIC at either larger bootstrap sample size or lower noise level.

  11. Experiments and modeling of ballistic penetration using an energy failure criterion

    Science.gov (United States)

    Dolinski, M.; Rittel, D.

    2015-10-01

    One of the most intricate problems in terminal ballistics is the physics underlying penetration and perforation. Several penetration modes are well identified, such as petalling, plugging, spall failure and fragmentation (Sedgwick, 1968). In most cases, the final target failure will combine those modes. Some of the failure modes can be due to brittle material behavior, but penetration of ductile targets by blunt projectiles, involving plugging in particular, is caused by excessive localized plasticity, with emphasis on adiabatic shear banding (ASB). Among the theories regarding the onset of ASB, new evidence was recently brought by Rittel et al. (2006), according to whom shear bands initiate as a result of dynamic recrystallization (DRX), a local softening mechanism driven by the stored energy of cold work. As such, ASB formation results from microstructural transformations, rather than from thermal softening. In our previous work (Dolinski et al., 2010), a failure criterion based on plastic strain energy density was presented and applied to model four different classical examples of dynamic failure involving ASB formation. According to this criterion, a material point starts to fail when the total plastic strain energy density reaches a critical value. Thereafter, the strength of the element decreases gradually to zero to mimic the actual material mechanical behavior. The goal of this paper is to present a new combined experimental-numerical study of ballistic penetration and perforation, using the above-mentioned failure criterion. Careful experiments are carried out using a single combination of AISI 4340 FSP projectiles and 25[mm] thick RHA steel plates, while the impact velocity, and hence the imparted damage, are systematically varied. We show that our failure model, which includes only one adjustable parameter in this present work, can faithfully reproduce each of the experiments without any further adjustment. Moreover, it is shown that the most common

  12. Experiments and modeling of ballistic penetration using an energy failure criterion

    Directory of Open Access Journals (Sweden)

    Dolinski M.

    2015-01-01

    Full Text Available One of the most intricate problems in terminal ballistics is the physics underlying penetration and perforation. Several penetration modes are well identified, such as petalling, plugging, spall failure and fragmentation (Sedgwick, 1968. In most cases, the final target failure will combine those modes. Some of the failure modes can be due to brittle material behavior, but penetration of ductile targets by blunt projectiles, involving plugging in particular, is caused by excessive localized plasticity, with emphasis on adiabatic shear banding (ASB. Among the theories regarding the onset of ASB, new evidence was recently brought by Rittel et al. (2006, according to whom shear bands initiate as a result of dynamic recrystallization (DRX, a local softening mechanism driven by the stored energy of cold work. As such, ASB formation results from microstructural transformations, rather than from thermal softening. In our previous work (Dolinski et al., 2010, a failure criterion based on plastic strain energy density was presented and applied to model four different classical examples of dynamic failure involving ASB formation. According to this criterion, a material point starts to fail when the total plastic strain energy density reaches a critical value. Thereafter, the strength of the element decreases gradually to zero to mimic the actual material mechanical behavior. The goal of this paper is to present a new combined experimental-numerical study of ballistic penetration and perforation, using the above-mentioned failure criterion. Careful experiments are carried out using a single combination of AISI 4340 FSP projectiles and 25[mm] thick RHA steel plates, while the impact velocity, and hence the imparted damage, are systematically varied. We show that our failure model, which includes only one adjustable parameter in this present work, can faithfully reproduce each of the experiments without any further adjustment. Moreover, it is shown that the

  13. Differentiation between Superficial and Deep Lobe Parotid Tumors by Magnetic Resonance Imaging: Usefulness of the Parotid Duct Criterion

    Energy Technology Data Exchange (ETDEWEB)

    Imaizumi, A.; Kuribayashi, A.; Okochi, K.; Yoshino, N.; Kurabayashi, T. (Oral and Maxillofacial Radiology, Graduate School, Tokyo Medical and Dental Univ., Tokyo (Japan)); Ishii, J. (Maxillofacial Surgery, Graduate School, Tokyo Medical and Dental Univ., Tokyo (Japan)); Sumi, Y. (Division of Oral and Dental Surgery, Dept. of Advanced Medicine, National Center for Geriatrics and Gerontology, Aichi (Japan))

    2009-08-15

    Background: The location of a parotid tumor affects the choice of surgery, and there is a risk of damaging the facial nerve during surgery. Thus, differentiation between superficial and deep lobe parotid tumors is important for appropriate surgical planning. Purpose: To evaluate the usefulness of using the parotid duct, in addition to the retromandibular vein, for differentiating between superficial and deep lobe parotid tumors on MR images. Material and Methods: Magnetic resonance images of 42 parotid tumors in 40 patients were reviewed to determine whether the tumor was located in the superficial or deep lobe. In each case, the retromandibular vein and the parotid duct were used to locate the tumor. The parotid duct was only used in cases where the tumor and the duct were visualized on the same image. Results: Using the retromandibular vein criterion, 71% of deep lobe and 86% of superficial lobe tumors were correctly diagnosed, providing an accuracy of 81%. However, the accuracy achieved when using the parotid duct criterion was 100%, although it could be applied to only 28 of the 42 cases. Based on these results, we defined the following diagnostic method: the parotid duct criterion is first applied, and for cases in which it cannot be applied, the retromandibular vein criterion is used. The accuracy of this method was 88%, which was better than that achieved using the retromandibular vein criterion alone. Conclusion: The parotid duct criterion is useful for determining the location of parotid tumors. Combining the parotid duct criterion with the retromandibular vein criterion might improve the diagnostic accuracy of parotid tumor location compared to using the latter criterion alone

  14. DETERMINATION OF THE Mn2+-F- BOND LENGTH USING A COMPLETE SPECTRUM CRITERION AND A NEXT NEAREST NEIGHBOR MODEL

    Institute of Scientific and Technical Information of China (English)

    Sun Wei-li; Li Zhao-min

    2000-01-01

    20ptA complete spectrum criterion and a next nearest neighbor model areproposed. Research indicates: 1) Using this criterion can remove thelong existing puzzle that different parameters produce different bondlengths. The criterion greatly improve the reliability of optical methodfor determining the Mn{2+-F- distance R. 2) The exponent nand coefficient K in the inverse power law 10Dq=KR-n areobviously affected by next nearest neighbor. 3) Considering the effectcan lead to a better result, the next nearest neighbor model is thusmore strict and reliable.

  15. Image subband coding using an information-theoretic subband splitting criterion

    Science.gov (United States)

    Bayazit, Ulug; Pearlman, William A.

    1995-03-01

    It has been proved recently that for Gaussian sources with memory an ideal subband split will produce a coding gain for scalar or vector quantization of the subbands. Following the methodology of the proofs, we outline a method for successively splitting the subbands of a source, one at a time to obtain the largest coding gain. The subband with the largest theoretical rate reduction (TRR) is determined and split at each step of the decomposition process. The TRR is the difference between the rate in optimal encoding of N-tuples from a Gaussian source (or subband) and the rate for the same encoding of its subband decomposition. The TRR is a monotone increasing function of a so-called spectral flatness ratio, which involves the products of the eigenvalues of the source (subband) and subband decomposition covariance matrices of order N. These eigenvalues are estimated by the variances of the Discrete Cosine Transform, which approximates those of the optimal Karhunen Loeve Transform. After the subband decomposition hierarchy or tree is determined through the criterion of maximal TRR, each subband is encoded with a variable rate entropy constrained vector quantizer. Optimal rate allocation to subbands is done with the BFOS algorithm which does not require any source modelling. We demonstrate the benefit of using the criterion by comparing coding results on a two-level low-pass pyramidal decomposition with coding results on a two-level decomposition obtained using the criterion. For 60 MCFD (Motion Compensated Frame Difference) frames of the Salesman sequence an average rate- distortion advantage of 0.73 dB and 0.02 bpp and for 30 FD (Frame Difference) frames of Caltrain image sequence an average rate-distortion advantage of 0.41 dB and 0.013 bpp are obtained with the optimal decomposition over low-pass pyramidal decomposition.

  16. Construct and criterion-related validation of nutrient profiling models: A systematic review of the literature.

    Science.gov (United States)

    Cooper, Sheri L; Pelly, Fiona E; Lowe, John B

    2016-05-01

    Nutrient profiling (NP) is defined as the science of ranking foods according to their nutritional composition for the purpose of preventing disease or promoting health. The application of NP is ultimately to assist consumers to make healthier food choices, and thus provide a cost effective public health strategy to reduce the incidence of diet-related chronic disease. To our knowledge, no review has assessed the evidence to confirm the validity of NP models. We conducted a systematic review to investigate the construct and criterion-related validity of NP models in ranking food according to their nutritional composition for the purpose of preventing disease and promoting health. We searched peer-reviewed research published to 30 June 2015 and used PUBMED, Global Health (CABI), and SCOPUS databases. Within study bias was assessed using an adapted version of the QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies -2) tool for all diagnostic studies and the Cochrane Collaboration's Risk of Bias tool for all non-diagnostic studies. The GRADE (Grades of Recommendation, Assessment, Development, and Evaluation) approach was used to guide our judgement of the quality of the body of evidence for each outcome measure. From a total of 83 studies, 69 confirmed the construct validity of NP models; however most of these studies contained methodological weaknesses. Six studies used objective external measures to confirm the criterion-related validity of NP models; which inherently improved quality. The overall quality of evidence on the accuracy of NP models was judged to be very low to moderate using the GRADE approach. Many carefully designed studies to establish both construct and criterion-related validity are necessary to authenticate the application of NP models and provide the evidence to support the current definition of NP. PMID:26850312

  17. The surface-forming energy release rate based fracture criterion for elastic-plastic crack propagation

    Science.gov (United States)

    Xiao, Si; Wang, He-Ling; Liu, Bin; Hwang, Keh-Chih

    2015-11-01

    The J-integral based criterion is widely used in elastic-plastic fracture mechanics. However, it is not rigorously applicable when plastic unloading appears during crack propagation. One difficulty is that the energy density with plastic unloading in the J-integral cannot be defined unambiguously. In this paper, we alternatively start from the analysis on the power balance, and propose a surface-forming energy release rate (ERR), which represents the energy available for separating the crack surfaces during the crack propagation and excludes the loading-mode-dependent plastic dissipation. Therefore the surface-forming ERR based fracture criterion has wider applicability, including elastic-plastic crack propagation problems. Several formulae are derived for calculating the surface-forming ERR. From the most concise formula, it is interesting to note that the surface-forming ERR can be computed using only the stress and deformation of the current moment, and the definition of the energy density or work density is avoided. When an infinitesimal contour is chosen, the expression can be further simplified. For any fracture behaviors, the surface-forming ERR is proven to be path-independent, and the path-independence of its constituent term, so-called Js-integral, is also investigated. The physical meanings and applicability of the proposed surface-forming ERR, traditional ERR, Js-integral and J-integral are compared and discussed. Besides, we give an interpretation of Rice paradox by comparing the cohesive fracture model and the surface-forming ERR based fracture criterion.

  18. An existential criterion for normal and abnormal personality in the works of Erich Fromm.

    Directory of Open Access Journals (Sweden)

    Kapustin S.A.

    2015-06-01

    Full Text Available This is the first of four articles scheduled for publication in this journal on the position people with normal and abnormal personalities take in regard to so-called existential dichotomies. The main objective of this article is to propose a new, existential criterion for normal and abnormal personality implicitly present in the works of Erich Fromm. According to this criterion, normal and abnormal personalities are determined, first, by special features of the content of their position regarding existential dichotomies, and, second, by particular aspects of the formation of this position. Such dichotomies, entitatively existent in all human life, are inherent, two-alternative contradictions. The position of a normal personality in its content orients one toward a contradictious predetermination of life in the form of existential dichotomies and the necessity of searching for compromise in resolving these dichotomies. This position is created on a rational basis with the person’s active participation. The position of an abnormal personality in its content subjectively denies a contradictious predetermination of life in the form of existential dichotomies and orients one toward a consistent, noncompetitive, and, as a consequence, one-sided way of life that doesn’t include self-determination. This position is imposed by other people on an irrational basis. Abnormal personality interpreted like this is one of the most important factors influencing the development of various kinds of psychological problems and mental disorders — primarily, neurosis. In the following three articles it will be shown that this criterion is also implicitly present in the theories of personality devised by Sigmund Freud, Alfred Adler, Carl Jung, Carl Rogers, and Viktor Frankl.

  19. Relation between Managers’ Traits with their Assessment of the Successful Criterion in Iran

    Directory of Open Access Journals (Sweden)

    Malikeh Beheshtifar

    2012-09-01

    Full Text Available One of the problems being investigated about human behavior is the recognition of the influential traits on the behavior formation. We can recognize individual behavior through splitting up the behavioral patterns into some smaller units namely the traits. One of the results of the survey of traits in behavior form is individual success. Recognizing the successful managers` characteristics enables us to describe the effective patterns in society and specify the definite traits leading to desirable behaviors in organization. This study has applied the correlation method. The statistical population include of 68 top managers in Kerman public organizations. To collect the data 3 questionnaires pertaining to personality characteristics, motivation characteristics and managers’ successful and to analyze data used SPSS software. The questionnaires’ validity and reliability were assessed to be 0.93 and 0. 90. The findings of this study indicate the positive and significant relation between managers’ personality traits such as ingenuity, supervisory ability, self-confidence, decisiveness and maturity with their assessment of the successful criterion. Furthermore, the positive and significant relation between the managers’ motivational characteristics such as need for job achievement, need for self – actualization with their assessment. However, no significant relation has been noticed between managers’ personality traits such as intelligence, affiliation to personal and humane with their assessment of the successful criterion. No significant relation between motivational characteristics of managers such as need for power, need for Bonus and need for job – security with their assessment of the successful criterion has been discerned either. The managers who have a positive assessment about their successful share specific personality and motivational traits. It leads them to follow the definite desirable behaviors bringing about

  20. The Reliability of a Criterion-Referenced Composite with the Parts of the Composite Having Different Cutting Scores.

    Science.gov (United States)

    Raju, Nambury S.

    1982-01-01

    Rajaratnam, Cronbach and Gleser's generalizability formula for stratified-parallel tests and Raju's coefficient beta are generalized to estimate the reliability of a composite of criterion-referenced tests, where the parts have different cutting scores. (Author/GK)

  1. A Note on the Blow-up Criterion of Smooth Solutions to the 3D Incompressible MHD Equations

    Institute of Scientific and Technical Information of China (English)

    Sadek GALA

    2012-01-01

    In this note,we will give a new proof of the blow-up criterion of smooth solutions to the 3D incompressible magneto-hydrodynamic equations by a simple application of Gagliardo-Nirenberg' s inequality.

  2. A New Ductile Fracture Criterion and Its Application to the Prediction of Forming Limit in Deep Drawing

    Institute of Scientific and Technical Information of China (English)

    Yuying YANG; Zhongqi YU; Xuechun LI; Zhenzhong SUN

    2003-01-01

    With considering the influence of equivalent plastic strain on void-damage and taking Lemaitre damage equivalent stress as plastic potential, based on continuous damage mechanics theory, a new criterion for ductile fracture is derived. The two key materia

  3. A comparative calculation of the wind turbines capacities on the basis of the L-{sigma} criterion

    Energy Technology Data Exchange (ETDEWEB)

    Menet, Jean-Luc; Valdes, Laurent-Charles; Menart, Bruno [Universite de Valenciennes et du Hainaut-Cambresis, Groupe de Recherche Energies et Environnement, Valenciennes, 59 (France)

    2001-04-01

    Usually, wind sites are equipped with fast-running Horizontal Axis Wind Turbines of the airscrew type, which has a high efficiency. In this article, the argument is put forward that the choice of a wind turbine must not be based only on high efficiency. We propose a comparative criterion adapted to the comparison of a horizontal axis wind turbine with a vertical axis wind turbine: the L-{sigma} criterion. This criterion consists in comparing wind turbines which intercept the same front width of wind, by allocating them a same reference value of the maximal mechanical stress on the blades or the paddles. On the basis of this criterion, a quantitative comparison points to a clear advantage of the Savonius rotors, because of their lower angular velocity, and provides some elements for the improvement of their rotor. (Author)

  4. Mutual information criterion for feature selection with application to classification of breast microcalcifications

    Science.gov (United States)

    Diamant, Idit; Shalhon, Moran; Goldberger, Jacob; Greenspan, Hayit

    2016-03-01

    Classification of clustered breast microcalcifications into benign and malignant categories is an extremely challenging task for computerized algorithms and expert radiologists alike. In this paper we present a novel method for feature selection based on mutual information (MI) criterion for automatic classification of microcalcifications. We explored the MI based feature selection for various texture features. The proposed method was evaluated on a standardized digital database for screening mammography (DDSM). Experimental results demonstrate the effectiveness and the advantage of using the MI-based feature selection to obtain the most relevant features for the task and thus to provide for improved performance as compared to using all features.

  5. On the Performance of Principal Component Liu-Type Estimator under the Mean Square Error Criterion

    Directory of Open Access Journals (Sweden)

    Jibo Wu

    2013-01-01

    Full Text Available Wu (2013 proposed an estimator, principal component Liu-type estimator, to overcome multicollinearity. This estimator is a general estimator which includes ordinary least squares estimator, principal component regression estimator, ridge estimator, Liu estimator, Liu-type estimator, r-k class estimator, and r-d class estimator. In this paper, firstly we use a new method to propose the principal component Liu-type estimator; then we study the superior of the new estimator by using the scalar mean squares error criterion. Finally, we give a numerical example to show the theoretical results.

  6. A NEW CRITERION FOR OCCURRENCE OF STICK-SLIP MOTION IN DRIVE MECHANISM

    Institute of Scientific and Technical Information of China (English)

    Ding Wenjing; Fan Shichao; Lu Mingwan

    2000-01-01

    This paper, using Karnopp's model of friction force and phase plane method, studies the stick-slip motion of the flexible drive mechanism. It is explained that a sudden drop of friction force is the essential source of stick-slip motion when the sliding is impending. A new criterion for occurrence of stick-slip motion is established.The stick-slip region and the stable region in a parameter plane are separated by a critical parameter curve. Moreover, for the stick-slip motion of the flexible drive mechanism without viscous damping, a parameter expression is obtained. The results may be used in design of the flexible drive mechanism.

  7. Model based matching using simulated annealing and a minimum representation size criterion

    Science.gov (United States)

    Ravichandran, B.; Sanderson, A. C.

    1992-01-01

    We define the model based matching problem in terms of the correspondence and transformation that relate the model and scene, and the search and evaluation measures needed to find the best correspondence and transformation. Simulated annealing is proposed as a method for search and optimization, and the minimum representation size criterion is used as the evaluation measure in an algorithm that finds the best correspondence. An algorithm based on simulated annealing is presented and evaluated. This algorithm is viewed as a part of an adaptive, hierarchical approach which provides robust results for a variety of model based matching problems.

  8. A comparison of three additive tree algorithms that rely on a least-squares loss criterion.

    Science.gov (United States)

    Smith, T J

    1998-11-01

    The performances of three additive tree algorithms which seek to minimize a least-squares loss criterion were compared. The algorithms included the penalty-function approach of De Soete (1983), the iterative projection strategy of Hubert & Arabie (1995) and the two-stage ADDTREE algorithm, (Corter, 1982; Sattath & Tversky, 1977). Model fit, comparability of structure, processing time and metric recovery were assessed. Results indicated that the iterative projection strategy consistently located the best-fitting tree, but also displayed a wider range and larger number of local optima. PMID:9854946

  9. Development and validation of an MRI reference criterion for defining a positive SIJ MRI in spondyloarthritis

    DEFF Research Database (Denmark)

    Weber, Ulrich; Zubler, Veronika; Pedersen, Susanne J;

    2012-01-01

    this MRI reference criterion, the cut-off for number of affected SIJ quadrants needed to reach a pre-defined specificity `0.90 was `2/`2 for BME and `1/`1 for erosion in cohorts A/B, and both lesions BME and/or erosion increased sensitivity without reducing specificity. CONCLUSION: This data-driven study...... using two inception cohorts and comparing clinical and MRI-based classification supports the case for including both erosion and BME to define a positive SIJ MRI for the classification of axial SpA. © 2012 by the American College of Rheumatology....

  10. Novel Mapping Design Criterion for BICM-ID with SquareQAM Constellations

    Institute of Scientific and Technical Information of China (English)

    刘林南; 费泽松; 赵胜辉; 匡镜明

    2003-01-01

    Mapping design criteria of bit-interleaved coded modulation with iterative decoding (BICM-ID) with square 16QAM are analyzed. Three of the existing criteria are analyzed and compared with each other. Through the comparison, two main characters of the mapping design criteria are found. They are the harmonic mean of the minimum squared Euclidean distance and the average of Hamming distances with the nearest Euclidean distance. Based on these two characters, a novel mapping design criterion is proposed and a label mapping named mixed mapping is searched according to it. Simulation results show that mixed mapping performs better than the other mappings in BICM-ID system.

  11. Strategy missile control system design using adaptive fuzzy control based on Popov stability criterion

    Science.gov (United States)

    Zhang, Jianling; An, Jinwen; Wang, Mina

    2005-11-01

    This paper describes the application and simulation of an adaptive fuzzy controller for a missile model. The fuzzy control system is tested using different values of fuzzy controller correctional factor on a nonlinear missile model. It is shown that the self-tuning fuzzy controller is well suited for controlling the pitch loop of the missile control system with air turbulence and parameter variety. The research shows that the Popov stability criterion could successfully guarantee the stability of the fuzzy system. It provides a good method for the design of missile control system. Simulation results suggest significant benefits from fuzzy logic in control task for missile pitch loop control.

  12. SETUP OF RESOLUTIVE CRITERION FOR SEDIMENT-RELATED DISASTER WARNING INFORMATION USING LOGISTIC REGRESSION ANALYSIS

    Science.gov (United States)

    Sugihara, Shigemitsu; Shinozaki, Tsuguhiro; Ohishi, Hiroyuki; Araki, Yoshinori; Furukawa, Kohei

    It is difficult to deregulate sediment-related disaster warning information, for the reason that it is difficult to quantify the risk of disaster after the heavy rain. If we can quantify the risk according to the rain situation, it will be an indication of deregulation. In this study, using logistic regression analysis, we quantified the risk according to the rain situation as the probability of disaster occurrence. And we analyzed the setup of resolutive criterion for sediment-related disaster warning information. As a result, we can improve convenience of the evaluation method of probability of disaster occurrence, which is useful to provide information of imminently situation.

  13. Relations between cubic equation, stress tensor decomposition, and von Mises yield criterion

    Institute of Scientific and Technical Information of China (English)

    Haoyuan GUO; Liyuan ZHANG; Yajun YIN; Yongxin GAO

    2015-01-01

    Inspired by Cardano’s method for solving cubic scalar equations, the addi-tive decomposition of spherical/deviatoric tensor (DSDT) is revisited from a new view-point. This decomposition simplifies the cubic tensor equation, decouples the spher-ical/deviatoric strain energy density, and lays the foundation for the von Mises yield criterion. Besides, it is verified that under the precondition of energy decoupling and the simplest form, the DSDT is the only possible form of the additive decomposition with physical meanings.

  14. A modified criterion for wave-induced momentary liquefaction of sandy seabed

    Directory of Open Access Journals (Sweden)

    Wen-Gang Qi

    2015-01-01

    Full Text Available The assessment of the wave-induced soil liquefaction plays a key role in the geotechnical design for offshore foundations. The underlying shortcomings of the existing momentary liquefaction criteria are identified and clarified by mechanism analyses and the recent field observations. A modified criterion for the wave-induced momentary liquefaction of a sandy seabed is given to describe the vertical pore-pressure distributions. An improved approximation of the momentary liquefaction depth is further presented. Parametric study of the effects of the saturation degree of soils indicates that this modification is significant for the evaluation of wave-induced momentary liquefaction.

  15. Ginzburg criterion for the mean-field to three-dimensional Ising crossover in polymer blends

    DEFF Research Database (Denmark)

    Schwahn, D.; Schmackers, T.; Mortensen, K.

    1995-01-01

    Composition fluctuations within the mean-field and three-dimensional Ising range were measured in a homogeneous binary polymer blend by small angle neutron scattering as a function of temperature and pressure. The experimental data were analyzed in terms of the crossover function of Belyakov and...... Kiselev [Physica A 190, 75 (1992)]. It is shown that the reduced-crossover-temperature, the Ginzburg number Gi, decreases with pressure sensitively, in accordance with the prediction of Belyakov and Kiselev. On the other hand, de Gennes' crossover criterion for polymer blends predicts an increase of Gi...

  16. On the Blow-up Criterion of Smooth Solutions to the MHD System in BMO Space

    Institute of Scientific and Technical Information of China (English)

    Bao-quan Yuan

    2006-01-01

    In this paper we study the blow-up criterion of smooth solutions to the incompressible magnetohydrodynamics system in BMO space. Let (u(x,t),b(x,t)) be smooth solutions in (0, T). It is shown that the solution (u(x, t), b(x, t)) can be extended beyond t = T if (u(x, t), b(x, t)) ∈ L1(0, T; BMO) or the vorticity(rot u(x, t), rot b(x, t)) ∈ L1 (0, T; BMO) or the deformation (Def u(x, t), Def b(x, t)) ∈ L1 (0, T; BMO).

  17. Is This Reliable Enough? Examining Classification Consistency and Accuracy in a Criterion-Referenced Test

    OpenAIRE

    Susanne Alger

    2016-01-01

    One important step for assessing the quality of a test is to examine the reliability of test score interpretation. Which aspect of reliability is the most relevant depends on what type of test it is and how the scores are to be used. For criterion-referenced tests, and in particular certification tests, where students are classified into performance categories, primary focus need not be on the size of error but on the impact of this error on classification. This impact can be described in ter...

  18. The instability transition for the restricted 3-body problem. III. The Lyapunov exponent criterion

    Science.gov (United States)

    Quarles, B.; Eberle, J.; Musielak, Z. E.; Cuntz, M.

    2011-09-01

    Aims: We establish a criterion for the stability of planetary orbits in stellar binary systems by using Lyapunov exponents and power spectra for the special case of the circular restricted 3-body problem (CR3BP). The criterion augments our earlier results given in the two previous papers of this series where stability criteria have been developed based on the Jacobi constant and the hodograph method. Methods: The centerpiece of our method is the concept of Lyapunov exponents, which are incorporated into the analysis of orbital stability by integrating the Jacobian of the CR3BP and orthogonalizing the tangent vectors via a well-established algorithm originally developed by Wolf et al. The criterion for orbital stability based on the Lyapunov exponents is independently verified by using power spectra. The obtained results are compared to results presented in the two previous papers of this series. Results: It is shown that the maximum Lyapunov exponent can be used as an indicator for chaotic behaviour of planetary orbits, which is consistent with previous applications of this method, particularly studies for the Solar System. The chaotic behaviour corresponds to either orbital stability or instability, and it depends solely on the mass ratio μ of the binary components and the initial distance ratio ρ0 of the planet relative to the stellar separation distance. Detailed case studies are presented for μ = 0.3 and 0.5. The stability limits are characterized based on the value of the maximum Lyapunov exponent. However, chaos theory as well as the concept of Lyapunov time prevents us from predicting exactly when the planet is ejected. Our method is also able to indicate evidence of quasi-periodicity. Conclusions: For different mass ratios of the stellar components, we are able to characterize stability limits for the CR3BP based on the value of the maximum Lyapunov exponent. This theoretical result allows us to link the study of planetary orbital stability to chaos

  19. A criterion for crack initiation and propagation in intact rocks under creep condition

    Institute of Scientific and Technical Information of China (English)

    CHEN You-liang(陈有亮); SUN Jun(孙钧)

    2003-01-01

    This paper presents a study on the criterion of crack initiation and propagation under creep conditions, which were investigated using specimens collected from outcropped sandstone rock formations. Beam specimens under three points bending were used in this investigation. The experimental result shows that due to creep deformation, rock crack will inevitably initiate and propagate after a time interval of sustained loading under a load of KI, which is less than fracture toughness KIC but not less than a constant marked as KIC2. KIC2 indicates the ability of rock to resist crack initiation and propagation under creep conditions and it is defined as creep fracture toughness.

  20. Resonance overlap criterion for H atom ionization by circularly polarized microwave fields

    Energy Technology Data Exchange (ETDEWEB)

    Sacha, K.; Zakrzewski, J. [Instytut Fizyki imienia Mariana Smoluchowskiego, Uniwersytet Jagiellonski, ul. Reymonta 4, 30-059 Krakow (Poland)

    1997-01-01

    The threshold for H atom ionization by circularly polarized microwave fields is discussed within the classical mechanics framework for high microwave frequencies. The Chirikov resonance overlap criterion predictions are compared with estimates obtained adopting the renormalization method. It is shown that the ionization threshold is highly sensitive to the helicity of microwaves. Among all possible initial electronic orbits, those of medium eccentricity are the first to ionize. The results obtained indicate that collisions with the nucleus play a negligible role for the onset of ionization. {copyright} {ital 1997} {ital The American Physical Society}

  1. H-atom ionization by elliptically polarized microwave fields: The overlap criterion

    Energy Technology Data Exchange (ETDEWEB)

    Sacha, K.; Zakrzewski, J. [Instytut Fizyki imienia Mariana Smoluchowskiego, Uniwersytet Jagiellonski, ulica Reymonta 4, 30-059 Krakow (Poland)

    1997-07-01

    The threshold for H-atom ionization by elliptically polarized microwave fields is discussed within the classical-mechanics framework using the Chirikov overlap criterion. It is shown that the trends observed in the recent experiment [M. R. W. Bellermann {ital et al.} Phys. Rev. Lett. {bold 76}, 892 (1996)] are qualitatively reproduced by the theory; the origin of the remaining discrepancy is discussed. Increased stability of some orbits with respect to the perturbation due to the elliptically polarized microwaves has been related to vanishing widths of the corresponding resonance islands. Analytic Chirikov overlap prediction is compared with results of numerical simulations. {copyright} {ital 1997} {ital The American Physical Society}

  2. Frequency-domain criterion for the chaos synchronization of time-delay power systems under linear feedback control

    Indian Academy of Sciences (India)

    Qian Lin; Xiaofeng Wu; Yun Chen

    2015-12-01

    This paper studies the global synchronization of non-autonomous, time-delay, chaotic power systems via linear state-error feedback control. The frequency domain criterion and the LMI criterion are proposed and applied to design the coupling matrix. Some algebraic criteria via a single-variable linear coupling are derived and formulated in simple algebraic inequalities. The effectiveness of the new criteria is illustrated with numerical examples.

  3. The Bimodality Index: A Criterion for Discovering and Ranking Bimodal Signatures from Cancer Gene Expression Profiling Data

    OpenAIRE

    Jing Wang; Sijin Wen; Fraser Symmans, W; Lajos Pusztai; Coombes, Kevin R.

    2009-01-01

    Motivation: Identifying genes with bimodal expression patterns from large-scale expression profiling data is an important analytical task. Model-based clustering is popular for this purpose. That technique commonly uses the Bayesian information criterion (BIC) for model selection. In practice, however, BIC appears to be overly sensitive and may lead to the identification of bimodally expressed genes that are unreliable or not clinically useful. We propose using a novel criterion, the bimodali...

  4. Modified Johnston Failure Criterion from Rock Mechanics to Predict the Ultimate Strength of Fiber Reinforced Polymer (FRP) Confined Columns

    OpenAIRE

    Zehra Canan Girgin

    2013-01-01

    The failure criteria from rock mechanics, Hoek-Brown and Johnston failure criteria, may be extended and modified to assess the ultimate compressive strength of axially loaded circular fiber reinforced polymer (FRP)-confined concrete columns. In addition to the previously modified Hoek-Brown criterion, in this study, the Johnston failure criterion is extended to scope of FRP-confined concrete, verified with the experimental data and compared with the significant relationships from the current ...

  5. An existential criterion for normal and abnormal personality in the works of Sigmund Freud and Alfred Adler

    OpenAIRE

    KAPUSTIN SERGEY A.

    2015-01-01

    This is the second in a series of four articles scheduled for publication in this journal. In the previous article I proposed a description of a new so-called existential criterion of normal and abnormal personality that is implicitly present in the works of Erich Fromm. According to this criterion, normal and abnormal personalities are determined, first, by special features of the content of their position regarding existential dichotomies that are natural to human beings and, second, by par...

  6. Energy analysis of stability on shallow tunnels based on non-associated flow rule and non-linear failure criterion

    Institute of Scientific and Technical Information of China (English)

    张佳华; 王成洋

    2015-01-01

    On the basis of upper bound theorem, non-associated flow rule and non-linear failure criterion were considered together. The modified shear strength parameters of materials were obtained with the help of the tangent method. Employing the virtual power principle and strength reduction technique, the effects of dilatancy of materials, non-linear failure criterion, pore water pressure, surface loads and buried depth, on the stability of shallow tunnel were studied. In order to validate the effectiveness of the proposed approach, the solutions in the present work agree well with the existing results when the non-associated flow rule is reduced to the associated flow rule and the non-linear failure criterion is degenerated to the linear failure criterion. Compared with dilatancy of materials, the non-linear failure criterion exerts greater impact on the stability of shallow tunnels. The safety factor of shallow tunnels decreases and the failure surface expands outward when the dilatancy coefficient decreases. While the increase of nonlinear coefficient, the pore water pressure coefficient, the surface load and the buried depth results in the small safety factor. Therefore, the dilatancy as well as non-linear failure criterion should be taken into account in the design of shallow tunnel supporting structure. The supporting structure must be reinforced promptly to prevent potential mud from gushing or collapse accident in the areas with abundant pore water, large surface load or buried depth.

  7. Evaluation of a strain based failure criterion for the multi-constituent composite model under shock loading

    Science.gov (United States)

    Key, Christopher T.; Schumacher, Shane C.; Alexander, C. Scott

    2015-09-01

    This study details and demonstrates a strain-based criterion for the prediction of polymer matrix composite material damage and failure under shock loading conditions. Shock loading conditions are characterized by high-speed impacts or explosive events that result in very high pressures in the materials involved. These material pressures can reach hundreds of kbar and often exceed the material strengths by several orders of magnitude. Researchers have shown that under these high pressures, composites exhibit significant increases in stiffness and strength. In this work we summarize modifications to a previous stress based interactive failure criterion based on the model initially proposed by Hashin, to include strain dependence. The failure criterion is combined with the multi-constituent composite constitutive model (MCM) within a shock physics hydrocode. The constitutive model allows for decomposition of the composite stress and strain fields into the individual phase averaged constituent level stress and strain fields, which are then applied to the failure criterion. Numerical simulations of a metallic sphere impacting carbon/epoxy composite plates at velocities up to 1000 m/s are performed using both the stress and strain based criterion. These simulation results are compared to experimental tests to illustrate the advantages of a strain-based criterion in the shock environment.

  8. Optimization of equivalent uniform dose using the L-curve criterion

    Energy Technology Data Exchange (ETDEWEB)

    Chvetsov, Alexei V; Dempsey, James F; Palta, Jatinder R [Department of Radiation Oncology, University of Florida, Gainesville, FL 32610-0385 (United States)

    2007-09-21

    Optimization of equivalent uniform dose (EUD) in inverse planning for intensity-modulated radiation therapy (IMRT) prevents variation in radiobiological effect between different radiotherapy treatment plans, which is due to variation in the pattern of dose nonuniformity. For instance, the survival fraction of clonogens would be consistent with the prescription when the optimized EUD is equal to the prescribed EUD. One of the problems in the practical implementation of this approach is that the spatial dose distribution in EUD-based inverse planning would be underdetermined because an unlimited number of nonuniform dose distributions can be computed for a prescribed value of EUD. Together with ill-posedness of the underlying integral equation, this may significantly increase the dose nonuniformity. To optimize EUD and keep dose nonuniformity within reasonable limits, we implemented into an EUD-based objective function an additional criterion which ensures the smoothness of beam intensity functions. This approach is similar to the variational regularization technique which was previously studied for the dose-based least-squares optimization. We show that the variational regularization together with the L-curve criterion for the regularization parameter can significantly reduce dose nonuniformity in EUD-based inverse planning.

  9. Automated criterion-based analysis for Cole parameters assessment from cerebral neonatal electrical bioimpedance spectroscopy measurements

    International Nuclear Information System (INIS)

    Hypothermia has been proven as an effective rescue therapy for infants with moderate or severe neonatal hypoxic ischemic encephalopathy. Hypoxia-ischemia alters the electrical impedance characteristics of the brain in neonates; therefore, spectroscopic analysis of the cerebral bioimpedance of the neonate may be useful for the detection of candidate neonates eligible for hypothermia treatment. Currently, in addition to the lack of reference bioimpedance data obtained from healthy neonates, there is no standardized approach established for bioimpedance spectroscopy data analysis. In this work, cerebral bioimpedance measurements (12 h postpartum) in a cross-section of 84 term and near-term healthy neonates were performed at the bedside in the post-natal ward. To characterize the impedance spectra, Cole parameters (R0, R∞, fC and α) were extracted from the obtained measurements using an analysis process based on a best measurement and highest likelihood selection process. The results obtained in this study complement previously reported work and provide a standardized criterion-based method for data analysis. The availability of electrical bioimpedance spectroscopy reference data and the automatic criterion-based analysis method might support the development of a non-invasive method for prompt selection of neonates eligible for cerebral hypothermic rescue therapy. (paper)

  10. Unidentified bright objects on brain MRI in children as a diagnostic criterion for neurofibromatosis type 1

    Energy Technology Data Exchange (ETDEWEB)

    Lopes Ferraz Filho, Jose R.; Pontes Munis, Marcos; Soares Souza, Antonio; Sanches, Rafael A. [Medical School in Sao Jose do Rio Preto, Imaging Department, Sao Jose do Rio Preto, Sao Paulo (Brazil); Goloni-Bertollo, Eni M.; Pavarino-Bertelli, Erika C. [Center of Research and Attendance in Neurofibromatosis, Sao Paulo (Brazil)

    2008-03-15

    Lesions of the brain denominated as unidentified bright objects (UBOs), which are not included in the diagnostic criteria for neurofibromatosis type 1 (NF1) established by the National Institutes of Health (NIH), have been detected by MRI. The purpose of this study was to investigate the possibility of including the presence of UBOs as a diagnostic criterion for NF1 in children. The study included 88 children between the ages of 2 and 18 years. The case group consisted of 40 children diagnosed with sporadic or familial NF1 according to the criteria established by the NIH. A control group consisted of 48 individuals referred for routine MRI of the brain for other complaints not related to NF1. UBOs were identified in 70% of the NF1 patients and in none of the control group. The sensitivity of the presence of UBOs for the diagnosis of NF1 was 70% (CI 53-83%), with a false-negative rate of 30% (CI 27-47%), a specificity of 100% (CI 86-100%) and a false-positive rate of 0% (CI 0-14%). Faced with the difficulties in diagnosing NF1 in children and the high frequency and specificity of the presence UBOs identified by MRI in our series, we recommend the inclusion of the presence UBOs as a diagnostic criterion for NF1 in children. (orig.)

  11. Dynamic analysis of fault rockburst based on gradient-dependent plasticity and energy criterion

    Institute of Scientific and Technical Information of China (English)

    Xuebin Wang; Xiaobin Yang; Zhihui Zhang; Yishan Pan

    2004-01-01

    Fault rockburst is treated as a strain localization problem under dynamic loading condition considering strain gradient and strain rate. As a kind of dynamic fracture phenomena, rockburst has characteristics of strain localization, which is considered as a one-dimensional shear problem subjected to normal compressive stress and tangential shear stress. The constitutive relation of rock material is bilinear (elastic and strain softening) and sensitive to shear strain rate. The solutions proposed based on gradientdependent plasticity show that intense plastic strain is concentrated in fault band and the thickness of the band depends on the characteristic length of rock material. The post-peak stiffness of the fault band was determined according to the constitutive parameters of rock material and shear strain rate. Fault band undergoing strain softening and elastic rock mass outside the band constitute a system and the instability criterion of the system was proposed based on energy theory. The criterion depends on the constitutive relation of rock material, the structural size and the strain rate. The static result regardless of the strain rate is the special case of the present analytical solution. High strain rate can lead to instability of the system.

  12. Shielding effect and emission criterion of a screw dislocation near an interfacial blunt crack

    Institute of Scientific and Technical Information of China (English)

    Song Hao-Peng; Fang Qi-Hong; Liu You-Wen

    2009-01-01

    Shielding effect and emission criterion of a screw dislocation near an interfacial blunt crack are dealt with in this paper.Utilizing the conformal mapping technique,the closed-form solutions are derived for complex potentials and stress fields due to a screw dislocation located near the interfacial blunt crack.The stress intensity factor on the crack tips and the critical stress intensity factor for dislocation emission axe also calculated.The influence of the orientation of the dislocation and the morphology of the blunt crack as well as the material elastic dissimilarity on the shielding effect and the emission criterion is discussed in detail.The results show that positive screw dislocations can reduce the stress intensity factor of the interfacial blunt crack tip(shielding effect).The shielding effect increases with the increase of the shear modulus of the lower half-plane,but it decreases with the increase of the dislocation azimuth angle.The critical loads at infinity for dislocation emission increases with the increase of emission angle and curvature radius of blunt crack tip,and the most probable angle for screw dislocation emission is zero.The present solutions contain previous results as special cases.

  13. IMPROVING SUPERVISED CLASSIFICATION OF DAILY ACTIVITIES LIVING USING NEW COST SENSITIVE CRITERION FOR C-SVM

    Directory of Open Access Journals (Sweden)

    M’hamed Bilal Abidine

    2013-11-01

    Full Text Available The growing population of elders in the society calls for a new approach in care giving. By inferring what activities elderly are performing in their houses it is possible to determine their physical and cognitive capabilities. In this paper we show the potential of important discriminative classifiers namely the Soft-Support Vector Machines (C-SVM, Conditional Random Fields (CRF and k-Nearest Neighbors (k-NN for recognizing activities from sensor patterns in a smart home environment. We address also the class imbalance problem in activity recognition field which has been known to hinder the learning performance of classifiers. Cost sensitive learning is attractive under most imbalanced circumstances, but it is difficult to determine the precise misclassification costs in practice. We introduce a new criterion for selecting the suitable cost parameter C of the C-SVM method. Through our evaluation on four real world imbalanced activity datasets, we demonstrate that C-SVM based on our proposed criterion outperforms the state-of-the-art discriminative methods in activity recognition.

  14. Boson peak and Ioffe-Regel criterion in amorphous siliconlike materials: The effect of bond directionality

    Science.gov (United States)

    Beltukov, Y. M.; Fusco, C.; Parshin, D. A.; Tanguy, A.

    2016-02-01

    The vibrational properties of model amorphous materials are studied by combining complete analysis of the vibration modes, dynamical structure factor, and energy diffusivity with exact diagonalization of the dynamical matrix and the kernel polynomial method, which allows a study of very large system sizes. Different materials are studied that differ only by the bending rigidity of the interactions in a Stillinger-Weber modelization used to describe amorphous silicon. The local bending rigidity can thus be used as a control parameter, to tune the sound velocity together with local bonds directionality. It is shown that for all the systems studied, the upper limit of the Boson peak corresponds to the Ioffe-Regel criterion for transverse waves, as well as to a minimum of the diffusivity. The Boson peak is followed by a diffusivity's increase supported by longitudinal phonons. The Ioffe-Regel criterion for transverse waves corresponds to a common characteristic mean-free path of 5-7 Å (which is slightly bigger for longitudinal phonons), while the fine structure of the vibrational density of states is shown to be sensitive to the local bending rigidity.

  15. The exact form of the Bohm criterion for a collisional plasma

    CERN Document Server

    Tsankov, Tsanko Vaskov

    2016-01-01

    A long-standing debate in the literature about the kinetic form of the Bohm criterion is resolved for plasmas with single positive ion species when transport is dominated by charge exchange collisions. The solution of the Boltzmann equation for the ions gives the exact form free of any divergence and contains an additional term that is not included in the classical result. This term includes collisional and geometric effects and leads to a noticeable correction. Further, the question is addressed whether the space charge argument at the bottom of the Bohm criterion can actually lead to a meaningful definition of the transition point between bulk and sheath. The analysis is supported by a numerical model and experiments, showing excellent agreement throughout. As a novelty in diagnostics, the theoretical results allow from the ion velocity distribution function (IVDF), measured at the wall, a reconstruction of the IVDF and the electric field at any point in the plasma. This property is used to reconstruct non-...

  16. Boson peak and Ioffe-Regel criterion in amorphous siliconlike materials: The effect of bond directionality.

    Science.gov (United States)

    Beltukov, Y M; Fusco, C; Parshin, D A; Tanguy, A

    2016-02-01

    The vibrational properties of model amorphous materials are studied by combining complete analysis of the vibration modes, dynamical structure factor, and energy diffusivity with exact diagonalization of the dynamical matrix and the kernel polynomial method, which allows a study of very large system sizes. Different materials are studied that differ only by the bending rigidity of the interactions in a Stillinger-Weber modelization used to describe amorphous silicon. The local bending rigidity can thus be used as a control parameter, to tune the sound velocity together with local bonds directionality. It is shown that for all the systems studied, the upper limit of the Boson peak corresponds to the Ioffe-Regel criterion for transverse waves, as well as to a minimum of the diffusivity. The Boson peak is followed by a diffusivity's increase supported by longitudinal phonons. The Ioffe-Regel criterion for transverse waves corresponds to a common characteristic mean-free path of 5-7 Å (which is slightly bigger for longitudinal phonons), while the fine structure of the vibrational density of states is shown to be sensitive to the local bending rigidity. PMID:26986404

  17. A new criterion to assess distributional homogeneity in hyperspectral images of solid pharmaceutical dosage forms

    Energy Technology Data Exchange (ETDEWEB)

    Sacré, Pierre-Yves, E-mail: pysacre@ulg.ac.be [University of Liege (ULg), Department of Pharmacy, CIRM, Laboratory of Analytical Chemistry, CHU, B36, 4000 Liege (Belgium); Lebrun, Pierre [Arlenda S.A., Avenue de l’Hopital, 1, B-4000 Liege (Belgium); Chavez, Pierre-François; Bleye, Charlotte De; Netchacovitch, Lauranne; Rozet, Eric [University of Liege (ULg), Department of Pharmacy, CIRM, Laboratory of Analytical Chemistry, CHU, B36, 4000 Liege (Belgium); Klinkenberg, Régis; Streel, Bruno [Galéphar Research Center M/F, rue du Parc Industriel 39, 6900 Marche-en-Famenne (Belgium); Hubert, Philippe; Ziemons, Eric [University of Liege (ULg), Department of Pharmacy, CIRM, Laboratory of Analytical Chemistry, CHU, B36, 4000 Liege (Belgium)

    2014-03-01

    Highlights: • DHI has been developed to assess distributional homogeneity in hyperspectral maps. • This criterion has been tested with simulated maps of different homogeneity. • A linear relationship is observed between homogeneity and DHI value. • DHI methodology has been applied on real samples. • A linear relationship is observed between DHI and content uniformity values. - Abstract: During galenic formulation development, homogeneity of distribution is a critical parameter to check since it may influence activity and safety of the drug. Raman hyperspectral imaging is a technique of choice for assessing the distributional homogeneity of compounds of interest. Indeed, the combination of both spectroscopic and spatial information provides a detailed knowledge of chemical composition and component distribution. Actually, most authors assess homogeneity using parameters of the histogram of intensities (e.g. mean, skewness and kurtosis). However, this approach does not take into account spatial information and loses the main advantage of imaging. To overcome this limitation, we propose a new criterion: Distributional Homogeneity Index (DHI). DHI has been tested on simulated maps and formulation development samples. The distribution maps of the samples were obtained without validated calibration model since different formulations were under investigation. The results obtained showed a linear relationship between content uniformity values and DHI values of distribution maps. Therefore, DHI methodology appears to be a suitable tool for the analysis of homogeneity of distribution maps even without calibration during formulation development.

  18. The Maximum Effective Moment Criterion (MEMC) and Its Implications in Structural Geology

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The Mohr-Coulomb criterion has been widely used to explain formation of fractures.However, it fails to explain large strain deformation that widely occurs in nature. There is presently a σ1-σ3 represents the yield strength of the related rock, L is a unit length and α is the angle between σ1and deformation bands. This criterion demonstrates that the maximum value appears at angles of ±54.7° to σ1 and there is a slight difference in the moment in the range of 55°±10°. The range covers the whole observations available from nature and experiments. Its major implications include: (1) it can be used to determine the stress state when the related deformation features formed; (2) it provides a new approach to determine the Wk of the related ductile shear zone if only the ratio of the vorticity and strain rate remains fixed; (3) It can be used to explain (a) the obtuse angle in the contraction direction of conjugate kink-bands and extensional crenulation cleavages, (b) formation of low-angle normal faults and high-angle reverse faults, (c) lozenge ductile shear zones in basement terranes, (d) some crocodile structures in seismic profiles and (e) detachment folds in foreland basins.

  19. Energy analysis of face stability of deep rock tunnels using nonlinear Hoek-Brown failure criterion

    Institute of Scientific and Technical Information of China (English)

    张佳华; 李永鑫; 许敬叔

    2015-01-01

    The nonlinear Hoek-Brown failure criterion was introduced to limit analysis by applying the tangent method. Based on the failure mechanism of double-logarithmic spiral curves on the face of deep rock tunnels, the analytical solutions of collapse pressure were derived through utilizing the virtual power principle in the case of pore water, and the optimal solutions of collapse pressure were obtained by using the optimization programs of mathematical model with regard of a maximum problem. In comparison with existing research with the same parameters, the consistency of change rule shows the validity of the proposed method. Moreover, parametric study indicates that nonlinear Hoek-Brown failure criterion and pore water pressure have great influence on collapse pressure and failure shape of tunnel faces in deep rock masses, particularly when the surrounding rock is too weak or under the condition of great disturbance and abundant ground water, and in this case, supporting measures should be intensified so as to prevent the occurrence of collapse.

  20. The Frequentist Information Criterion (FIC): The unification of information-based and frequentist inference

    CERN Document Server

    LaMont, Colin H

    2015-01-01

    The failure of the information-based Akaike Information Criterion (AIC) in the context of singular models can be rectified by the definition of a Frequentist Information Criterion (FIC). FIC applies a frequentist approximation to the computation of the model complexity, which can be estimated analytically in many contexts. Like AIC, FIC can be understood as an unbiased estimator of the model predictive performance and is therefore identical to AIC for regular models in the large-observation-number limit ($N\\rightarrow \\infty$) . In the presence of unidentifiable parameters, the complexity exhibits a more general, non-AIC-like scaling ($\\gg N^0$). For instance, both BIC-like ($\\propto\\log N$) and Hannan-Quinn-like ($\\propto \\log \\log N$) scaling with observation number $N$ are observed. Unlike the Bayesian model selection approach, FIC is free from {\\it ad hoc} prior probability distributions and appears to be widely applicable to model selection problems. Finally we demonstrate that FIC (information-based inf...

  1. A Research on the Adaptability of Collision Criterion1,2

    Science.gov (United States)

    Li, Jia-Long; Xiong, Jian-Ning; Xu, Xiao-Li; Zhao, Chang-Yin

    2015-07-01

    With the rising number of space debris, people pay more and more attention to the space debris collision avoidance system (SDCAS). In the early 1990s, the BOX method is commonly used as a collision criterion to decide whether the avoiding maneuver is necessary for a spacecraft. But this method has low practicability, so the method of collision probability is developed. This method takes the relative distance and other geometrical parameters at the en time of two space objects into consideration. However, the mathematical model of this collision criterion depends highly on the orbit errors, so it may lead to some inaccurate results. In this paper, the rendezvous of two orbits are sim, and the errors are considered, then the relative distance at the moment of their closest approach and the collision probability are calculated. The re indicate that the covariance of position errors plays an indispensable role in measuring the risk of collision. When the precision of orbit prediction is not very good, it is better to combine the BOX method and the collision probability method in the SDCAS.

  2. Determine the optimal carrier selection for a logistics network based on multi-commodity reliability criterion

    Science.gov (United States)

    Lin, Yi-Kuei; Yeh, Cheng-Ta

    2013-05-01

    From the perspective of supply chain management, the selected carrier plays an important role in freight delivery. This article proposes a new criterion of multi-commodity reliability and optimises the carrier selection based on such a criterion for logistics networks with routes and nodes, over which multiple commodities are delivered. Carrier selection concerns the selection of exactly one carrier to deliver freight on each route. The capacity of each carrier has several available values associated with a probability distribution, since some of a carrier's capacity may be reserved for various orders. Therefore, the logistics network, given any carrier selection, is a multi-commodity multi-state logistics network. Multi-commodity reliability is defined as a probability that the logistics network can satisfy a customer's demand for various commodities, and is a performance indicator for freight delivery. To solve this problem, this study proposes an optimisation algorithm that integrates genetic algorithm, minimal paths and Recursive Sum of Disjoint Products. A practical example in which multi-sized LCD monitors are delivered from China to Germany is considered to illustrate the solution procedure.

  3. Suboptimal criterion setting in a perceptual choice task with asymmetric reinforcement.

    Science.gov (United States)

    Stüttgen, Maik C; Kasties, Nils; Lengersdorf, Daniel; Starosta, Sarah; Güntürkün, Onur; Jäkel, Frank

    2013-06-01

    Performance on psychophysical tasks is influenced by a variety of non-sensory factors, most notably the magnitude or probability of reinforcement following correct responses. When reinforcement probability is unequal for hits and correct rejections, signal detection theory specifies an optimal decision criterion which maximizes the number of reinforcers. We subjected pigeons to a task in which six different stimuli (shades of gray) had to be assigned to one of two categories. Animals were confronted with asymmetric reinforcement schedules in which correct responses to five of the stimuli were reinforced with a probability of 0.5, while correct responses to the remaining stimulus were extinguished. The subjects' resultant choice probabilities clearly deviated from those predicted by a maximization account. More specifically, the magnitude of the choice bias increased with the distance of the to-be-extinguished stimulus to the category boundary, a pattern opposite to that posited by maximization. The present and a previous set of results in which animals performed optimally can be explained by a simple choice mechanism in which a variable decision criterion is constantly updated according to a leaky integration of incomes attained from both response options.

  4. The research on algorithm of criterion limit of monitoring point under the effect of multi-electromagnetic radiation pollution sources in the spatial field

    Institute of Scientific and Technical Information of China (English)

    Liu,Bo; Wang,Huimin; Yuan,Haixia; Zhou,Jie

    2003-01-01

    In terms of algorithmic problem of criterion limit of monitoring point under the effect of multi-electromagnetic radiation pollution sources in the spatial field, we put up a formula of criterion limit of monitoring point based on distance factor algorithm. The algorithm not only can solve the computations of criterion limits of monitoring point at certain time under the effect of multi-electromagnetic radiation pollution sources, but can compute the criterion limits of all monitoring points at any time,which has important instructions for working out electromagnetic environment criterion.

  5. Geoscience Education and Public Outreach AND CRITERION 2: MAKING A BROADER IMPACT

    Science.gov (United States)

    Marlino, M.; Scotchmoor, J. G.

    2005-12-01

    The geosciences influence our daily lives and yet often go unnoticed by the general public. From the moment we listen to the weather report and fill-up our cars for the daily commute, until we return to our homes constructed from natural resources, we rely on years of scientific research. The challenge facing the geosciences is to make explicit to the public not only the criticality of the research whose benefits they enjoy, but also to actively engage them as partners in the research effort, by providing them with sufficient understanding of the scientific enterprise so that they become thoughtful and proactive when making decisions in the polling booth. Today, there is broad recognition within the science and policy community that communication needs to be more effective, more visible, and that the public communication of the scientific enterprise is critical not only to its taxpayer support, but also to maintenance of a skilled workforce and the standard of living expected by many Americans. In 1997, the National Science Board took the first critical step in creating a cultural change in the scientific community by requiring explicit consideration of the broader impacts of research in every research proposal. The so-called Criterion 2 has catalyzed a dramatic shift in expectations within the geoscience community and an incentive for finding ways to encourage the science research community to select education and public outreach as a venue for responding to Criterion 2. In response, a workshop organized by the University of California Museum of Paleontology and the Digital Library for Earth System Education (DLESE) was held on the Berkeley campus May 11-13, 2005. The Geoscience EPO Workshop purposefully narrowed its focus to that of education and public outreach. This workshop was based on the premise that there are proven models and best practices for effective outreach strategies that need to be identified and shared with research scientists. Workshop

  6. A Mean-Variance Criterion for Economic Model Predictive Control of Stochastic Linear Systems

    DEFF Research Database (Denmark)

    Sokoler, Leo Emil; Dammann, Bernd; Madsen, Henrik;

    2014-01-01

    -variance strategies, but it does not account for the variance of the uncertain parameters. Openloop simulations suggest that a single-stage mean-variance approach yields a significantly lower operating cost than the certainty equivalence strategy. In closed-loop, the single-stage formulation is overly conservative......, which results in a high operating cost. For this case, a two-stage extension of the mean-variance approach provides the best trade-off between the expected cost and its variance. It is demonstrated that by using a constraint back-off technique in the specific case study, certainty equivalence EMPC can......Stochastic linear systems arise in a large number of control applications. This paper presents a mean-variance criterion for economic model predictive control (EMPC) of such systems. The system operating cost and its variance is approximated based on a Monte-Carlo approach. Using convex relaxation...

  7. A Novel Criterion for Optimum MultilevelCoding Systems in Mobile Fading Channels

    Institute of Scientific and Technical Information of China (English)

    YUAN Dongfeng; WANG Chengxiang; YAO Qi; CAO Zhigang

    2001-01-01

    A novel criterion that is "capac-ity rule" and "mapping rule" for the design of op-timum MLC scheme over mobile fading channels isproposed.According to this theory,the performanceof multilevel coding with multistage decoding schemes(MLC/MSD) in mobile fading channels is investi-gated,in which BCH codes are chosen as componentcodes,and three mapping strategies with 8ASK mod-ulation are used.Numerical results indicate that whencode rates of component codes in MLC scheme are de-signed based on "capacity rule",the performance ofthe system with block partitioning (BP) is optimumfor Rayleigh fading channels,while the performance ofthe system with Ungerboeck partioning (UP) is bestfor AWGN channels.

  8. Relay Selection Scheme for AF Relay Network based on Cost Function Criterion

    Directory of Open Access Journals (Sweden)

    Kanghee Lee

    2013-10-01

    Full Text Available An amplify-and-forward (AF wireless relay network consisting of a one-source-one-destination node pair and cooperative multiple N relay nodes is proposed in three adverse wireless communication environments, i.e., jamming, node geometry, and channel uncertainty. Based on the minimum mean square error (MMSE criterion, the optimal amplifying relay matrix in three adverse wireless environments with the relay power constraint is derived. In addition, the MMSE cost function behavior in three adverse environments is analytically investigated using the proposed optimal relay amplifying matrix. Finally, using the cost function value, the relay selection scheme in adverse wireless communication environments is presented, which is the main contribution of this paper

  9. The early stop heuristic: A new convergence criterion for K-means

    Science.gov (United States)

    Mexicano, A.; Rodríguez, R.; Cervantes, S.; Montes, P.; Jiménez, M.; Almanza, N.; Abrego, A.

    2016-06-01

    In this paper, an enhanced version of the K-Means algorithm that incorporates a new convergence criterion is presented. The largest centroid displacement at each iteration was used as mean to define whether the algorithm stops or not its execution. Computational experiments showed that in general, the Early Stop Heuristic is able to reduce the execution time of the standard version without a significant quality reduction. According to the experimentation, the Early Stop Heuristic reached a time reduction up to 87.06% only a quality reduction of 2.46% for the Transactions dataset, the worst case occurred when the Skin instance was grouped into 200 clusters obtaining a 79.04% in reduction time, and a 4.27% in quality reduction.

  10. Resonant Excitation of Disk Oscillations in Deformed Disks VII: Stability Criterion in MHD Systems

    CERN Document Server

    Kato, Shoji

    2013-01-01

    In a disk with an oscillatory deformation from an axisymmetric state with frequency $\\omega_{\\rm D}$ and azimuthal wavenumber $m_{\\rm D}$, a set of two normal mode oscillations with frequency and azimuthal wavenumber being ($\\omega_1$, $m_1$) and ($\\omega_2$, $m_2$) resonantly couple through the disk deformation, when the resonant conditions ($\\omega_1+\\omega_2+\\omega_{\\rm D}=0$ and $m_1+m_2+m_{\\rm D}=0$) are satisfied. In the case of hydrodynamical disks, the resonance amplifies the set of the oscillations if $(E_1/\\omega_1)(E_2/\\omega_2)>0$ (Kato 2013b), where $E_1$ and $E_2$ are wave energies of the two oscillations with $\\omega_1$ and $\\omega_2$, respectively. In this paper we show that this instability criterion is still valid even when the oscillations are ideal MHD ones in magnetized disks, if the displacements associated with the oscillations vanish on the boundary of the system.

  11. Distributed optimization using virtual and real game strategies for multi-criterion aerodynamic design

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    This paper introduces the virtual and real game concepts to investigate multi-criterion optimization for optimum shape design in aerodynamics. The constrained adjoint meth- odology is used as the basic optimizer. Furthermore, the above is combined with the vir- tual and real game strategies to treat single-point/multi-point airfoil optimization. In a symmetric Nash Game, each optimizer attempts to optimize one’s own target with ex- change of symmetric information with others. A Nash equilibrium is just the compromised solution among the multiple criteria. Several kinds of airfoil splitting and design cases are shown for the utility of virtual and real game strategies in aerodynamic design. Successful design results confirm the validity and efficiency of the present design method.

  12. Uplift Capacity of Shallow Anchors Based on the Generalized Nonlinear Failure Criterion

    Directory of Open Access Journals (Sweden)

    Zou Jin-feng

    2016-01-01

    Full Text Available The shape of rapture surface for shallow anchors was presented and the effects of parameters on the shape of rapture surface were analyzed. Based on the generalized nonlinear failure criterion and the limit equilibrium principle, an approach, which takes into account the shape of rapture surface, dip angle of shallow anchors, and varieties of rock and soil mass, is proposed. The effects of different parameters on ultimate uplift force of shallow anchors are discussed. In order to validate the practicability of the proposed formula, a comparison between the theoretical solutions and local test results is conducted. The agreement shows that the proposed formula is effective. The results of the proposed approach show that the ultimate uplift capacity of shallow anchor increases nonlinearly with the shape coefficient linearly increasing. The values of ultimate uplift force local test are in the range of the results of the proposed method with shape coefficient from 0 to 1.

  13. Logarithmical regularity criterion of the three-dimensional Boussinesq equations in terms of the pressure

    Science.gov (United States)

    Mechdene, Mohamed; Gala, Sadek; Guo, Zhengguang; Ragusa, Alessandra Maria

    2016-10-01

    This work establishes a sufficient condition for the regularity criterion of the Boussinesq equation in terms of the derivative of the pressure in one direction. It is shown that if the partial derivative of the pressure {partial 3π } satisfies the logarithmical Serrin-type condition int0TVert partial 3π (s)Vert_{L^{λ }}q/1+ln (1+Vert θ Vert_{L4)} {d}s < ∞ quad {with}quad2/q+3/λ =7/4quad {and}quad12/7 < λ ≤ ∞, then the solution {(u,θ )} remains smooth on {[0,T]}. Compared to the Navier-Stokes result, there is a logarithmic correction involving {θ} in the denominator.

  14. A viscoelastic-plastic constitutive model with Mohr-Coulomb yielding criterion for sea ice dynamics

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    A new viscoelastic-plastic (VEP) constitutive model for sea ice dynamics was developed based on continuum mechanics. This model consists of four components: Kelvin-Vogit viscoelastic model, Mohr-Coulomb yielding criterion, associated normality flow rule for plastic rehololgy, and hydrostatic pressure. The numerical simulations for ice motion in an idealized rectangular basin were made using smoothed particle hydrodynamics (SPH) method, and compared with the analytical solution as well as those based on the modified viscous plastic(VP) model and static ice jam theory. These simulations show that the new VEP modelcan simulate ice dynamics accurately. The new constitutive model was further applied to simulate ice dynamics of the Bohai Sea and compared with the traditional VP, and modified VP models. The results of the VEP model are compared better with the satellite remote images, and the simulated ice conditions in the JZ20-2 oil platform area were more reasonable.

  15. Startup of Plasma Current in J-TEXT Tokamak Prompted by the Hα Line Emission Criterion

    Institute of Scientific and Technical Information of China (English)

    GAO Li; ZHUANG Ge; HU Xiwei; ZHANG Ming

    2009-01-01

    An Hα line-emission detection system was developed on the joint texas experimental tokamak (J-TEXT), which is used to determine the Hα emission level during the gas breakdown and hereafter to control the startup of the plasma current. The detector consists of an Hα in-terference filter, a focusing lens, a photodiode and a preamplifier. In the J-TEXT operation, the Hα emission is taken as a monitor signal which is highly sensitive to the generation of a plasma.Furthermore, the power supply control system using the above signal as an input is capable of de-termining whether and when to fire the Ohmic heating capacitor banks, which are applied to drive the plasma current ramp-up. The experimental results confirm that the Hα emission criterion is acceptable for controlling the plasma current promotion in the J-TEXT tokamak.

  16. A Criterion for the Complete Deposition of Magnetic Beads on the Walls of Microchannels.

    Science.gov (United States)

    Pallares, Jordi

    2016-01-01

    This paper analyzes numerical simulations of the trajectories of magnetic beads in a microchannel, with a nearby permanent cubical magnet, under different flow and magnetic conditions. Analytically derived local fluid velocities and local magnetic forces have been used to track the particles. A centered position and a lateral position of the magnet above the microchannel are considered. The computed fractions of deposited particles on the walls are compared successfully with a new theoretically derived criterion that imposes a relation between the sizes of the magnet and the microchannel and the particle Stokes and Alfvén numbers to obtain the complete deposition of the flowing particles on the wall. In the cases in which all the particles, initially distributed uniformly across the section of the microchannel, are deposited on the walls, the simulations predict the accumulation of the major part of particles on the wall closest to the magnet and near the first half of the streamwise length of the magnet.

  17. Performance Indices Based Optimal Tunning Criterion for Speed Control of DC Drives Using GA

    Directory of Open Access Journals (Sweden)

    Deepti Singh

    2014-12-01

    Full Text Available This paper presents a framework to carry out a simulation to tune the speed controller gains for known input of DC drive system. The objective is to find the optimal controller gains (proportional and integral in a closed loop system. Various performance indices have been considered as optimal criterion in this work. The optimal gain values have been obtained by conventional and Genetic Algorithm (GA based optimization methods. The study has been conducted on a simulink model of three phase converter controlled direct current (DC drive with current and speed control strategy. The results show that the GA based tunning provided better solutions as compared to conventional optimization methods based tunning.

  18. Using the Correlation Criterion to Position and Shape RBF Units for Incremental Modelling

    Institute of Scientific and Technical Information of China (English)

    Xun-Xian Wang; Sheng Chen; Chris J. Harris

    2006-01-01

    A novel technique is proposed for the incremental construction of sparse radial basis function (RBF) networks.The correlation between an RBF regressor and the training data is used as the criterion to position and shape the RBF node, and it is shown that this is equivalent to incrementally minimise the modelling mean square error. A guided random search optimisation method, called the repeated weighted boosting search, is adopted to append RBF nodes one by one in an incremental regression modelling procedure. The experimental results obtained using the proposed method demonstrate that it provides a viable alternative to the existing state-of-the-art modelling techniques for constructing parsimonious RBF models that generalise well.

  19. A fracture criterion for widespread cracking in thin-sheet aluminum alloys

    Science.gov (United States)

    Newman, J. C., Jr.; Dawicke, D. S.; Sutton, M. A.; Bigelow, C. A.

    1993-01-01

    An elastic-plastic finite-element analysis was used with a critical crack-tip-opening angle (CTOA) fracture criterion to model stable crack growth in thin-sheet 2024-T3 aluminum alloy panels with single and multiple-site damage (MSD) cracks. Comparisons were made between critical angles determined from the analyses and those measured with photographic methods. Calculated load against crack extension and load against crack-tip displacement on single crack specimens agreed well with test data even for large-scale plastic deformations. The analyses were also able to predict the stable tearing behavior of large lead cracks in the presence of stably tearing MSD cracks. Small MSD cracks significantly reduced the residual strength for large lead cracks.

  20. Direct method for second-order sensitivity analysis of modal assurance criterion

    Science.gov (United States)

    Lei, Sheng; Mao, Kuanmin; Li, Li; Xiao, Weiwei; Li, Bin

    2016-08-01

    A Lagrange direct method is proposed to calculate the second-order sensitivity of modal assurance criterion (MAC) values of undamped systems. The eigenvalue problem and normalizations of eigenvectors, which augmented by using some Lagrange multipliers, are used as the constraints of the Lagrange functional. Once the Lagrange multipliers are determined, the sensitivities of MAC values can be evaluated directly. The Lagrange direct method is accurate, efficient and easy to implement. A simply supported beam is utilized to check the accuracy of the proposed method. A frame is adopted to validate the predicting capacity of the first- and second-order sensitivities of MAC values. It is shown that the computational costs of the proposed method can be remarkably reduced in comparison with those of the indirect method without loss of accuracy.

  1. A blowup criterion for viscous, compressible, and heat-conductive magnetohydrodynamic flows

    Science.gov (United States)

    Du, Lili; Wang, Yongfu

    2015-09-01

    In this paper, we proved a blowup criterion for the two-dimensional (2D) viscous, compressible, and heat-conducting magnetohydrodynamic (MHD) flows for Cauchy problem, which depends only on the divergence of the velocity vector field, as well as for the case of bounded domain with Dirichlet boundary conditions. This result indicates that the nature of the blowup for compressible models of viscous media in 2D space is similar to the barotropic compressible Navier-Stokes equations and does not depend on further sophistication of the MHD model. More precisely, taking into account the magnetic effects and heat conductivity does not introduce any new features in the blowup mechanism of full MHD flows, especially, which is independent of the temperature and the magnetic field. The results also imply the global regularity of the strong solution to compressible MHD flows, provided that velocity divergence remains bounded.

  2. Variable selection based on entropic criterion and its application to the debris-flow triggering

    CERN Document Server

    Chen, C; Tseng, C Y; Chen, Chien-chih; Dong, Jia-Jyun; Tseng, Chih-Yuan

    2006-01-01

    We propose a new data analyzing scheme, the method of minimum entropy analysis (MEA), in this paper. New MEA provides a quantitative criterion to select relevant variables for modeling the physical system interested. Such method can be easily extended to various geophysical/geological data analysis, where many relevant or irrelevant available measurements may obscure the understanding of the highly complicated physical system like the triggering of debris-flows. After demonstrating and testing the MEA method, we apply this method to a dataset of debris-flow occurrences in Taiwan and successfully find out three relevant variables, i.e. the hydrological form factor, numbers and areas of landslides, to the triggering of observed debris-flow events due to the 1996 Typhoon Herb.

  3. The leg-to-body ratio as a human aesthetic criterion.

    Science.gov (United States)

    Swami, Viren; Einon, Dorothy; Furnham, Adrian

    2006-12-01

    There are surprisingly few empirical studies on the aesthetic appeal of human legs, examining such variables as length or shape. The human legs are conspicuous in erotic contexts, but few studies have experimentally tested preferences for longer legs. This study examined the utility of the human leg-to-body ratio (LBR) as a specific aesthetic criterion among 71 British undergraduates. Participants rated for physical attractiveness line drawings that varied in five levels of LBR. The results showed that a longer LBR was preferred as maximally attractive in women, whereas a shorter LBR was preferred in men. Evolutionary psychological and socio-cultural explanations for this aesthetic preference are discussed, and the study's limitations are considered. PMID:18089235

  4. A Criterion for Elliptic Curves with Second Lowest 2-Power in L(1)(Ⅱ)

    Institute of Scientific and Technical Information of China (English)

    Chun Lai ZHAO

    2005-01-01

    Let D = p1p2… pm, where pi, p2,...,pm are distinct rational primes with p1 ≡ p2 ≡3(mod 8), pi ≡1(mod 8)(3 ≤ i ≤ m), and m is any positive integer. In this paper, we give a simple combinatorial criterion for the value of the complex L-function of the congruent elliptic curve ED2 : y2 = x3-D2x at s = 1, divided by the period ω defined below, to be exactly divisible by 22m-2, the second lowest 2-power with respect to the number of the Gaussian prime factors of D. As a corollary, we obtain a new series of non-congruent numbers whose prime factors can be arbitrarily many. Our result is in accord with the predictions of the conjecture of Birch and Swinnerton-Dyer.

  5. Study on fatigue life evaluation of structural component based on crack growth criterion

    International Nuclear Information System (INIS)

    As one of the practical application of fracture mechanics, fatigue life evaluation method based on crack growth criterion has been diffusing in various field of technology in order to determine the rational and reliable life of structural components. The fatigue life by this method is evaluated based on the fatigue crack growth analysis from defects, while many problems, such as the influence of residual stress on the crack growth behavior, the effect of overloading, and evaluation method for multiple surface cracks, are not sufficiently solved yet. In this paper, the above problems are treated, and based on some exprimental data some simple mehtods for fatigue life evaluation are proposed regarding the above problems. Verification of the proposed methods are shown in the paper by comparing with some experimental results, and the applicability of the proposed method is also examined by the fatigue test of pipes with cracks in the inner surface. (author)

  6. Singularity and Bohm criterion in hot positive ion species in the electronegative ion sources

    Science.gov (United States)

    Aslaninejad, Morteza; Yasserian, Kiomars

    2016-05-01

    The structure of the discharge for a magnetized electronegative ion source with two species of positive ions is investigated. The thermal motion of hot positive ions and the singularities involved with it are taken into account. By analytical solution of the neutral region, the location of the singular point and also the values of the plasma parameter such as electric potential and ion density at the singular point are obtained. A generalized Bohm criterion is recovered and discussed. In addition, for the non-neutral solution, the numerical method is used. In contrast with cold ion plasma, qualitative changes are observed. The parameter space region within which oscillations in the density and potential can be observed has been scanned and discussed. The space charge behavior in the vicinity of edge of the ion sources has also been discussed in detail.

  7. New technologies and possibilities of breast cancer staging by the criterion N ex vivo

    Directory of Open Access Journals (Sweden)

    Sh. Kh. Gantsev

    2010-01-01

    Full Text Available The study was undertaken to improve breast cancer (BC staging by the criterion N ex vivo, by applying the up-to-date ultrasound and microsurgical technologies. A LySonix 3000® with PulseSelectTM system was used to expose lymph nodes and vessels. Axillary adipose tissue classically exposed was examined in 70 patients with Stages II-III BC. Lymph vessels and nodes were separated by the sonolipodestruction technique. The findings permit sonolipodestruction to be used for ex vivo total lymph dissection for BC as a method that improves its N-staging. Sonolymphodissection opens up fresh opportunities for studying the anatomic structure of the lymphatic apparatus.

  8. Distributed optimization using virtual and real game strategies for multi-criterion aerodynamic design

    Institute of Scientific and Technical Information of China (English)

    TANG ZhiLi; BAI Wen; DONG Jun

    2008-01-01

    This paper introduces the virtual and real game concepts to investigate multi-criterion optimization for optimum shape design in aerodynamics. The constrained acljoint meth-odology is used as the basic optimizer. Furthermore, the above is combined with the vir-tual and real game strategies to treat single-point/multi-point airfoil optimization. In a symmetric Nash Game, each optimizer attempts to optimize one's own target with ex-change of symmetric information with others. A Nash equilibrium is just the compromised solution among the multiple criteria. Several kinds of airfoil splitting and design cases are shown for the utility of virtual and real game strategies in aerodynamic design. Successful design results confirm the validity and efficiency of the present design method.

  9. A strict response criterion yields a mirror effect in the novelty paradigm.

    Science.gov (United States)

    Aberg, Carola S; Nilsson, Lars-Göran

    2003-12-01

    According to the novelty/encoding hypothesis (NEH; Tulving & Kroll, 1995), efficacy of encoding information into long-term memory depends on the movelty of the information. Recognition accuracy is higher for novel than for previously familiarized material. This novelty effect is not a mirror effect: the superiority of novel over familiar items is not found in the hit rates but only in the false-alarm rates. The main result in the present replication study was that novel hit rates were higher than familiar ones when the most confident responses were examined separately, and thus a mirror effect could be demonstrated for these data, for both the low- and the high-frequency words. Similarly, the word-frequency effect on hits was stronger when a stricter response criterion was applied. It was concluded that the novelty effect and the word-frequency effect are more similar to one another than has hitherto been thought. PMID:15030108

  10. Augmented Lagrange Based on Modified Covariance Matching Criterion Method for DOA Estimation in Compressed Sensing

    Science.gov (United States)

    Si, Weijian; Qu, Xinggen; Liu, Lutao

    2014-01-01

    A novel direction of arrival (DOA) estimation method in compressed sensing (CS) is presented, in which DOA estimation is considered as the joint sparse recovery from multiple measurement vectors (MMV). The proposed method is obtained by minimizing the modified-based covariance matching criterion, which is acquired by adding penalties according to the regularization method. This minimization problem is shown to be a semidefinite program (SDP) and transformed into a constrained quadratic programming problem for reducing computational complexity which can be solved by the augmented Lagrange method. The proposed method can significantly improve the performance especially in the scenarios with low signal to noise ratio (SNR), small number of snapshots, and closely spaced correlated sources. In addition, the Cramér-Rao bound (CRB) of the proposed method is developed and the performance guarantee is given according to a version of the restricted isometry property (RIP). The effectiveness and satisfactory performance of the proposed method are illustrated by simulation results. PMID:24678272

  11. An extended-source spatial acquisition process based on maximum likelihood criterion for planetary optical communications

    Science.gov (United States)

    Yan, Tsun-Yee

    1992-01-01

    This paper describes an extended-source spatial acquisition process based on the maximum likelihood criterion for interplanetary optical communications. The objective is to use the sun-lit Earth image as a receiver beacon and point the transmitter laser to the Earth-based receiver to establish a communication path. The process assumes the existence of a reference image. The uncertainties between the reference image and the received image are modeled as additive white Gaussian disturbances. It has been shown that the optimal spatial acquisition requires solving two nonlinear equations to estimate the coordinates of the transceiver from the received camera image in the transformed domain. The optimal solution can be obtained iteratively by solving two linear equations. Numerical results using a sample sun-lit Earth as a reference image demonstrate that sub-pixel resolutions can be achieved in a high disturbance environment. Spatial resolution is quantified by Cramer-Rao lower bounds.

  12. Towards fully automatic modelling of the fracture process in quasi-brittle and ductile materials: a unified crack growth criterion

    Institute of Scientific and Technical Information of China (English)

    Zhen-jun YANG; Guo-hua LIU

    2008-01-01

    Fully automatic finite element (FE) modelling of the fracture process in quasi-brittle materials such as concrete and rocks and ductile materials such as metals and alloys, is of great significance in assessing structural integrity and presents tremendous challenges to the engineering community. One challenge lies in the adoption of an objective and effective crack propagation criterion. This paper proposes a crack propagation criterion based on the principle of energy conservation and the cohesive zone model (CZM). The virtual crack extension technique is used to calculate the differential terms in the criterion. A fully-automatic discrete crack modelling methodology, integrating the developed criterion, the CZM to model the crack, a simple remeshing procedure to accommodate crack propagation, the J2 flow theory implemented within the incremental plasticity framework to model the ductile materials, and a local arc-length solver to the nonlinear equation system, is developed and implemented in an in-house program. Three examples, i.e., a plain concrete beam with a single shear crack, a reinforced concrete (RC) beam with multiple cracks and a compact-tension steel specimen, are simulated. Good agreement between numerical predictions and experimental data is found, which demonstrates the applicability of the criterion to both quasi-brittle and ductile materials.

  13. Development of a criterion method to determine peak mechanical power output in a countermovement jump.

    Science.gov (United States)

    Owen, Nick J; Watkins, James; Kilduff, Liam P; Bevan, Huw R; Bennett, Mark A

    2014-06-01

    There is a general agreement that the most valid method of measuring peak lower-body mechanical power output (LBPP) in a countermovement jump (CMJ) is by analysis of the corresponding vertical component of the ground reaction force (VGRF)-time history of the jump. However, there is no published standard protocol. The purpose of this study was to establish a standard protocol. The variables necessary to define a valid and reliable CMJ method were: (a) vertical force range, (b) force sampling and integration frequency, (c) method of integration, (d) determination of body weight (BW), and (e) determination of the initiation of the CMJ. Countermovement jumps off a force platform (FP) were performed by 15 male professional rugby players. The 5 variables were then optimized to maximize the reliability and validity of the measure of LBPP. Errors of times BW (using a 16-bit analog to digital converter), (b) 1,000 Hz, (c) Simpson's rule or the trapezoidal rule, (d) mean VGRF for 1 second of quiet standing immediately before jump signal, and (e) 30 ms before the instant BW ± 5 SD is exceeded after the jump signal. Peak lower-body power output was most sensitive to variables 4 and 5. It was concluded that this study has established a standard protocol for the criterion method of measuring peak power in a CMJ using an FP. As all other estimates and less reliable methods of determining LBPP in a CMJ rely on the FP method for calibration, it is proposed that this protocol be used as the basis of future criterion measures using a FP. PMID:24276298

  14. Construct and criterion validity of the Euro Qol-5D in patients with systemic lupus erythematosus.

    Directory of Open Access Journals (Sweden)

    Su-li Wang

    Full Text Available OBJECTIVE: To investigate the construct and criterion validity of the Euro Qol-5D (EQ-5D, which allows quality-adjusted life-years to be calculated, in patients with systemic lupus erythematosus (SLE. METHODS: Consecutive SLE patients who had been followed at the Renji Hospital, School of Medicine, Shanghai Jiao Tong University were recruited. Cross-sectional correlations of the EQ-5D with equivalent domains in disease-specific health-related quality of life (HRQoL, LupusQol, Systemic Lupus Erythematosus Disease Activity Index (SLEDAI measures, the Systemic Lupus International Collaborating Clinics Damage Index (SDI, and patient characteristics were tested. Discriminant validity to assess the ability to distinguish between patients of different disease severity was assessed. There also were evaluations of ceiling and floor effects. RESULTS: 240 patients were recruited in total. The EQ-5D correlated moderately to strongly with all domains of the LupusQoL (r: 0.44-0.7 apart from intimate relationships (r = 0.25 and body image (r = 0.18. There was moderate negative correlation between EQ-5D and clinical assessment of disease, SLEDAI (r = -0.589 and SDI (r = -0.509. When compared with equivalent domains on LupusQoL, there was good construct validity in EQ-5D (r: 0.631-0.812. EQ-5D could also discriminate patients with varied disease severity (according SLEDAI and SDI. There was no floor effect in EQ-5D but the ceiling effect remains strong (34%. CONCLUSION: Our results provide sufficient evidence that the EQ-5D displays construct and criterion validity for use in SLE patients. Disease-specific measures of HRQoL used alongside may be a better choice.

  15. Whole-Body Reaching Movements Formulated by Minimum Muscle-Tension Change Criterion.

    Science.gov (United States)

    Kudo, Naoki; Choi, Kyuheong; Kagawa, Takahiro; Uno, Yoji

    2016-05-01

    It is well known that planar reaching movements of the human shoulder and elbow joints have invariant features: roughly straight hand paths and bell-shaped velocity profiles. The optimal control models with the criteria of smoothness or precision, which determine a unique movement pattern, predict such features of hand trajectories. In this letter on expanding the research on simple arm reaching movements, we examine whether the smoothness criteria can be applied to whole-body reaching movements with many degrees of freedom. Determining a suitable joint trajectory in the whole-body reaching movement corresponds to the optimization problem with constraints, since body balance must be maintained during a motion task. First, we measured human joint trajectories and ground reaction forces during whole-body reaching movements, and confirmed that subjects formed similar movements with common characteristics in the trajectories of the hand position and body center of mass. Second, we calculated the optimal trajectories according to the criteria of torque and muscle-tension smoothness. While the minimum torque change trajectories were not consistent with the experimental data, the minimum muscle-tension change model was able to predict the stereotyped features of the measured trajectories. To explore the dominant effects of the extension from the torque change to the muscle-tension change, we introduced a weighted torque change cost function. Considering the maximum voluntary contraction (MVC) force of the muscle as the weighting factor of each joint torque, we formulated the weighted torque change cost as a simplified version of the minimum muscle-tension change cost. The trajectories owing to the minimum weighted torque change criterion also showed qualitative agreement with the common features of the measured data. Proper estimation of the MVC forces in the body joints is essential to reproduce human whole-body movements according to the minimum muscle-tension change

  16. An improved procedure for gene selection from microarray experiments using false discovery rate criterion

    Directory of Open Access Journals (Sweden)

    Yang Mark CK

    2006-01-01

    Full Text Available Abstract Background A large number of genes usually show differential expressions in a microarray experiment with two types of tissues, and the p-values of a proper statistical test are often used to quantify the significance of these differences. The genes with small p-values are then picked as the genes responsible for the differences in the tissue RNA expressions. One key question is what should be the threshold to consider the p-values small. There is always a trade off between this threshold and the rate of false claims. Recent statistical literature shows that the false discovery rate (FDR criterion is a powerful and reasonable criterion to pick those genes with differential expression. Moreover, the power of detection can be increased by knowing the number of non-differential expression genes. While this number is unknown in practice, there are methods to estimate it from data. The purpose of this paper is to present a new method of estimating this number and use it for the FDR procedure construction. Results A combination of test functions is used to estimate the number of differentially expressed genes. Simulation study shows that the proposed method has a higher power to detect these genes than other existing methods, while still keeping the FDR under control. The improvement can be substantial if the proportion of true differentially expressed genes is large. This procedure has also been tested with good results using a real dataset. Conclusion For a given expected FDR, the method proposed in this paper has better power to pick genes that show differentiation in their expression than two other well known methods.

  17. Criterion distances and correlates of active transportation to school in Belgian older adolescents

    Directory of Open Access Journals (Sweden)

    De Bourdeaudhuij Ilse

    2010-12-01

    Full Text Available Abstract Background Since physical activity levels in older adolescents have the potential to be increased by stimulating active transportation to school (ATS, the most important correlates of ATS should be determined before developing interventions, especially in those adolescents for whom the distance to school is feasible for active commuting. The main aims of this study were to determine criterion distances for ATS in Belgian older adolescents, to examine multidimensional correlates of ATS in adolescents living within a feasible distance from school and to investigate the associations of ATS with total physical activity and with other physical activities besides ATS. Methods In total, 1281 older adolescents (17-18 years from 20 general secondary schools in East- and West-Flanders completed a questionnaire on physical activity behaviors, demographic factors and psychosocial and physical environmental correlates of physical activity. Distance to school was objectively measured using Routenet online route planner. Results In total, 58.4% of the participants commuted actively to school. The criterion distance for ATS could be set at eight kilometers for cycling and two kilometers for walking. For those adolescents living within a feasible distance for ATS, gender, smoking status, walkability of the neighborhood and social modeling were associated with transportation mode choice. ATS was positively associated with total physical activity, but not significantly related to min/week of other physical activities. Conclusions For older adolescents living within eight kilometers of their school, interventions taking into account the correlates found to be related to ATS could possibly be effective to enhance ATS and to increase total physical activity levels. In the context of the overall physical activity decline in adolescence, also interventions targeting physical activity behaviors of adolescents living further away from school might be needed, but

  18. The Effect of Vitamin C Vaginal Tablets on Amsel Criterion in Patients with Bacterial Vaginosis

    Directory of Open Access Journals (Sweden)

    F Godarzi

    2011-10-01

    Full Text Available Background & aim: Bacterial vaginosis is the common cause of vaginitis among women of reproductive ages. Amsel criterion is the most accurate and applicable diagnosis method for bacterial vaginosis. The aim of the present study was to evaluate the effect of vitamin C vaginal tablets on the Amsel criterion. Methods: After confirmed diagnosis of bacterial vaginosis to Amsel criteria (having at least 3 out of the 4 characteristic symptoms including discharge, fishy odor, vaginal pH≥4.5, and presence of >20% of clue cell, 60 non pregnant women of 15-45 years of reproductive ages were enrolled in the present randomized clinical trail. The women were randomly assigned into two group (30 person in each group to receive either 250 mg vaginal tablet of vitamin C, once a day, for 6 days or 75% metronidazole vaginal gel (5 gr once a day for 5 days. Results obtained from both groups were compared for demographics features, history and baseline clinical pictures. Participants were evaluated in follow-up visits (after treatment. Results: After one week of applying of vitamin C vaginal tablets, 66.7% of cases had normal form of vaginal discharge,7 0% had negative whiff test, 40% had vaginal pH<4.5 and in 86.7% clue cell was less than 20% (p=0.0001. Conclusion: This study showed that vitamin C vaginal tablet has a significant effect on four of Amsel criteria especially on clue cell which is important for diagnosis of bacterial vaginosis.

  19. Optimal Base Wavelet Selection for ECG Noise Reduction Using a Comprehensive Entropy Criterion

    Directory of Open Access Journals (Sweden)

    Hong He

    2015-09-01

    Full Text Available The selection of an appropriate wavelet is an essential issue that should be addressed in the wavelet-based filtering of electrocardiogram (ECG signals. Since entropy can measure the features of uncertainty associated with the ECG signal, a novel comprehensive entropy criterion Ecom based on multiple criteria related to entropy and energy is proposed in this paper to search for an optimal base wavelet for a specific ECG signal. Taking account of the decomposition capability of wavelets and the similarity in information between the decomposed coefficients and the analyzed signal, the proposed Ecom criterion integrates eight criteria, i.e., energy, entropy, energy-to-entropy ratio, joint entropy, conditional entropy, mutual information, relative entropy, as well as comparison information entropy for optimal wavelet selection. The experimental validation is conducted on the basis of ECG signals of sixteen subjects selected from the MIT-BIH Arrhythmia Database. The Ecom is compared with each of these eight criteria through four filtering performance indexes, i.e., output signal to noise ratio (SNRo, root mean square error (RMSE, percent root mean-square difference (PRD and correlation coefficients. The filtering results of ninety-six ECG signals contaminated by noise have verified that Ecom has outperformed the other eight criteria in the selection of best base wavelets for ECG signal filtering. The wavelet identified by the Ecom has achieved the best filtering performance than the other comparative criteria. A hypothesis test also validates that SNRo, RMSE, PRD and correlation coefficients of Ecom are significantly different from those of the shape-matched approach (α = 0.05 , two-sided t- test.

  20. A Fortran 90 Program for the Generalized Order-Restricted Information Criterion

    Directory of Open Access Journals (Sweden)

    Rebecca M. Kuiper

    2013-09-01

    Full Text Available The generalized order-restricted information criterion (GORIC is a generalization of the Akaike information criterion such that it can evaluate hypotheses that take on specific, but widely applicable, forms (namely, closed convex cones for multivariate normal linear models. It can examine the traditional hypotheses H0: ?1,1 = = ?t,k and Hu: ?1,1, , ?t,k and hypotheses containing simple order restrictions Hm: ?1,1 ? ? ?t,k, where any "?" may be replaced by "=" and m is the model/hypothesis index; with ?h,j the parameter for the h-th dependent variable and the j-th predictor in a t-variate regression model with k predictors (which might include the intercept. But, the GORIC can also be applied to restrictions of the form Hm: R1? = r1; R2? ? r2, with ? a vector of length tk, R1 a cm1 tk matrix, r1 a vector of length cm1, R2 a cm2 tk matrix, and r2 a vector of length cm2. It should be noted that [R1T, R2T]T should be of full rank when [R1T, R2T]T ? 0. In practice, this implies that one cannot examine range restrictions (e.g., 0 < ?1,1 < 2 or ?1,2 < ?1,1 < 2?1,2 with the GORIC. A Fortran 90 program is presented, which enables researchers to compute the GORIC for hypotheses in the context of multivariate regression models. Additionally, an R package called goric is made by Daniel Gerhard and the first author.

  1. A systematic review of reliability and objective criterion-related validity of physical activity questionnaires

    Directory of Open Access Journals (Sweden)

    Helmerhorst Hendrik JF

    2012-08-01

    Full Text Available Abstract Physical inactivity is one of the four leading risk factors for global mortality. Accurate measurement of physical activity (PA and in particular by physical activity questionnaires (PAQs remains a challenge. The aim of this paper is to provide an updated systematic review of the reliability and validity characteristics of existing and more recently developed PAQs and to quantitatively compare the performance between existing and newly developed PAQs. A literature search of electronic databases was performed for studies assessing reliability and validity data of PAQs using an objective criterion measurement of PA between January 1997 and December 2011. Articles meeting the inclusion criteria were screened and data were extracted to provide a systematic overview of measurement properties. Due to differences in reported outcomes and criterion methods a quantitative meta-analysis was not possible. In total, 31 studies testing 34 newly developed PAQs, and 65 studies examining 96 existing PAQs were included. Very few PAQs showed good results on both reliability and validity. Median reliability correlation coefficients were 0.62–0.71 for existing, and 0.74–0.76 for new PAQs. Median validity coefficients ranged from 0.30–0.39 for existing, and from 0.25–0.41 for new PAQs. Although the majority of PAQs appear to have acceptable reliability, the validity is moderate at best. Newly developed PAQs do not appear to perform substantially better than existing PAQs in terms of reliability and validity. Future PAQ studies should include measures of absolute validity and the error structure of the instrument.

  2. Criterion of magnetic saturation and simulation of nonlinear magnetization for a linear multi-core pulse transformer

    International Nuclear Information System (INIS)

    The linear multi-core pulse transformer is an important primary driving source used in pulsed power apparatus for the production of dense plasm owing to its compact, relatively low-cost and easy-to-handle characteristics. The evaluation of the magnetic saturation of the transformer cores is essential to the transformer design, because the energy transfer efficiency of the transformer will degrade significantly after magnetic saturation. This work proposes analytical formulas of the criterion of magnetic saturation for the cores when the transformer drives practical loads. Furthermore, an electric circuit model based on a dependent source treatment for simulating the electric behavior of the cores related to their nonlinear magnetization is developed using the initial magnetization curve of the cores. The numerical simulation with the model is used to evaluate the validity of the criterion. Both the criterion and the model are found to be in agreement with the experimental data

  3. Criterion of Magnetic Saturation and Simulation of Nonlinear Magnetization for a Linear Multi-core Pulse Transformer

    Institute of Scientific and Technical Information of China (English)

    曾正中; 蒯斌; 孙凤举; 丛培天; 邱爱慈

    2002-01-01

    The linear multi-core pulse transformer is an important primary driving source usedin pulsed power apparatus for the production of dense plasma owing to its compact, relatively low-cost and easy-to-handle characteristics. The evaluation of the magnetic saturation of the transformer cores is essential to the transformer design, because the energy transfer efficiency of the transformer will degrade significantly after magnetic saturation. This work proposes analytical formulas of the criterion of magnetic saturation for the cores when the transformer drives practical loads. Furthermore, an electric circuit model based on a dependent source treatment for simulating the electric behavior of the cores related to their nonlinear magnetization is developed using the initial magnetization curve of the cores. The numerical simulation with the model is used to evaluate the validity of the criterion. Both the criterion and the model are found to be in agreement with the experimental data.

  4. A study on the instability criterion for the stratified flow in horizontal pipe at cocurrent flow conditions

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Chang Kyung [Korea Electric Power Research Institute, Taejon (Korea, Republic of)

    1997-12-31

    This paper presents a theoretical approach of the instability criterion from stratified to nonstratified flow in horizontal pipe at cocurrent flow conditions. The new theoretical instability criterion for the stratified and nonstratified flow transition in horizontal pipe has been developed by hyperbolic equations in two-phase flow. Critical flow condition criterion and onset of slugging at cocurrent flow condition correspond to zero and imaginary characteristics which occur when the hyperbolicity of a stratified two-phase flow is broken, respectively. Through comparison between results predicted by the present flow is broken, respectively. Through comparison between results predicted by the present theory and the Kukita et al. [1] experimental data of pipes, it is shown that they are in good agreement with data. 4 refs., 2 figs. (Author)

  5. Criterion-Related Validity of Sit-and-Reach Tests for Estimating Hamstring and Lumbar Extensibility: a Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Daniel Mayorga-Vega

    2014-03-01

    Full Text Available The main purpose of the present meta-analysis was to examine the scientific literature on the criterion-related validity of sit-and-reach tests for estimating hamstring and lumbar extensibility. For this purpose relevant studies were searched from seven electronic databases dated up through December 2012. Primary outcomes of criterion-related validity were Pearson´s zero-order correlation coefficients (r between sit-and-reach tests and hamstrings and/or lumbar extensibility criterion measures. Then, from the included studies, the Hunter- Schmidt´s psychometric meta-analysis approach was conducted to estimate population criterion- related validity of sit-and-reach tests. Firstly, the corrected correlation mean (rp, unaffected by statistical artefacts (i.e., sampling error and measurement error, was calculated separately for each sit-and-reach test. Subsequently, the three potential moderator variables (sex of participants, age of participants, and level of hamstring extensibility were examined by a partially hierarchical analysis. Of the 34 studies included in the present meta-analysis, 99 correlations values across eight sit-and-reach tests and 51 across seven sit-and-reach tests were retrieved for hamstring and lumbar extensibility, respectively. The overall results showed that all sit-and-reach tests had a moderate mean criterion-related validity for estimating hamstring extensibility (rp = 0.46-0.67, but they had a low mean for estimating lumbar extensibility (rp = 0. 16-0.35. Generally, females, adults and participants with high levels of hamstring extensibility tended to have greater mean values of criterion-related validity for estimating hamstring extensibility. When the use of angular tests is limited such as in a school setting or in large scale studies, scientists and practitioners could use the sit-and-reach tests as a useful alternative for hamstring extensibility estimation, but not for estimating lumbar extensibility.

  6. A criterion for quantum teleportation of an arbitrary N-particle state via a 2N-particle quantum channel

    International Nuclear Information System (INIS)

    A criterion for he tquantum teleportation of an arbitrary N-particle state via a 2N-particle quantum channel is presented by introducing a term of the “judgment operator. Using the criterion, not only the qualitative judgment of the possibility of successful teleportation can be made but also the quantitative calculation of the probability of successful teleportation can be explicitly given. In addition, a new genuine four-qubit entangled state is proposed, which could not belong to the category of previously known states under stochastic local operations and classical communication. (general)

  7. The mechanism and criterion of tectonic zone around karstic collapse column reactivation-induced water-conducting

    Institute of Scientific and Technical Information of China (English)

    XU Jin-peng; FU Zhi-liang; SONG Yang; CHENG Jiu-long

    2005-01-01

    In order to study the mechanism of tectonic zone around karstic collapse column reacts to leak water and prevent water invasion in mine. According to the character of the surrounding cracks- penetrated water KCC, The fracture mechanics theory can be used to study the propagation and perforation process of cracks and hitches around the KCC. The criterion of crack start rupture and the length of secondary crack and criterion of crack propagation have been attained. The influencing factors of KCC reacts to water conduction were analyzed.

  8. Analytical criterion for porous solids containing cylindrical voids in an incompressible matrix exhibiting tension-compression asymmetry

    Science.gov (United States)

    Cazacu, Oana; Stewart, Joel B.

    2013-05-01

    A new analytic plastic potential is developed using a rigorous limit analysis approach. Conditions of homogeneous boundary strain rate are imposed on every cylinder concentric with the cavity. It is shown that, due to the tension-compression asymmetry of the incompressible matrix, the third invariant of the stress deviator has a strong influence on the yielding of the porous solid. New and intriguing results are obtained; namely, for axisymmetric loadings and plane strain conditions, the stress state at yielding is not hydrostatic. In the case when the matrix has the same yield in tension as in compression, the new criterion reduces to Gurson's criterion for cylindrical voids.

  9. Magnetic field at the center of a vortex: A new criterion for the classification of the superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jun-Ping, E-mail: wangjunping@gmail.com

    2015-07-17

    Magnetic response of a superconductor depends on the thermodynamic stability of a vortex in the material. Here we show that the vortex stability has a close relation with the ratio of the magnetic field at the vortex core center to the thermodynamic critical field. This finding provides a new criterion for the classification of the superconductors according to their magnetic responses. - Highlights: • The intrinsic relation between vortex stability and the magnitude of the magnetic field at the vortex core center is revealed. • A new criterion for the classification of the superconductors is proposed. • Numerical solutions for the magnetic field at the vortex core center are presented.

  10. Distribution of the LR criterion Up,m,n as a marginal distribution of a generalized Dirichlet model

    Directory of Open Access Journals (Sweden)

    Seemon Thomas

    2013-05-01

    Full Text Available The density of the likelihood ratio criterion Up,m,n is expressed in terms of a marginal density of a generalized Dirichlet model having a specific set of parameters. The exact distribution of the likelihood ratio criterion so obtained has a very simple and general format for every p . It provides an easy and direct method of computation of the exact p -value of Up,m,n . Various types of properties and relations involving hypergeometric series are also established.

  11. The criterion of subscale sufficiency and its application to the relationship between static capillary pressure, saturation and interfacial areas

    Science.gov (United States)

    Kurzeja, Patrick

    2016-05-01

    Modern imaging techniques, increased simulation capabilities and extended theoretical frameworks, naturally drive the development of multiscale modelling by the question: which new information should be considered? Given the need for concise constitutive relationships and efficient data evaluation; however, one important question is often neglected: which information is sufficient? For this reason, this work introduces the formalized criterion of subscale sufficiency. This criterion states whether a chosen constitutive relationship transfers all necessary information from micro to macroscale within a multiscale framework. It further provides a scheme to improve constitutive relationships. Direct application to static capillary pressure demonstrates usefulness and conditions for subscale sufficiency of saturation and interfacial areas.

  12. Estimation of the enterprise marketing activity by criterion on future abilities creation to form demand

    Directory of Open Access Journals (Sweden)

    L.V. Potrashkova

    2015-09-01

    Full Text Available The aim of the article. The aim of the article is to develop theoretic grounds to calculate enterprise marketing activity factors, which characterize its long term consequences with production demand formation in future. The results of the analysis. One suggests to estimate enterprise marketing activity by criterion on future enterprise abilities creation to form production demand. That’s why enterprise marketing activity factors have to include enterprise marketing potential factors. These factors allow to evaluate perspective consequences of the marketing activity and its impact on future enterprise abilities. The resulting estimation of the enterprise marketing potential is maximal profit value, which enterprise will receive in the prognosticated period with existing marketing resources at the period beginning (such as consumers’ awareness about enterprise; consumers’ expectations concerning production quality level; consumers’ loyalty level; service level at the enterprise; developed conceptions of products and service without considering limitations, put with producing and financial abilities of the given enterprise. Mathematic instrument to calculate enterprise marketing activity potential is investigated optimal dynamic model, which allows to calculate potential profit of the enterprise with existing marketing resources. This model allows to estimate future consequences of the existing marketing resources, which are results of the previous marketing activity at the enterprise, and, thus, it evaluates enterprise marketing activity in reporting period. In order to consider different duration and importance of marketing consequences, to estimate enterprise marketing activity, the evaluating system of three levels in marketing potential is suggested. They are strategic, tactic and operative levels. Conclusions and directions for further research. Business activity is based on the renewing processes, and enterprise builds its own

  13. A Criterion for Crack Initiation and Propagation of Intact Rocks under Creep Condition

    Institute of Scientific and Technical Information of China (English)

    陈有亮; 岳中琦; 等

    2002-01-01

    The mechanism and criterion of crack initiation and propagation of rocks were investigated by many researchers,And the creep behaviour of rocks was also theoretically and experimentally studied by some scientists and engineers.The characteristics of crack initation and propagation of rocks under creep condition.however,are very improtant for rock engineering and still not paid enough attention by researchers,In this paper,the criterion and mechanism of crack initiation and propagation under creep condition were investigated using specimens collected from sandstone rock formations outcropping in the Emei Mountain,the Sichuan Province of China.Cuboid specimens under three point bending were used in this investigation.All specimens were classified into four sorts and used for Mode-I fracutre of creep frcture tests.The experimental result shows that due to creep deformation.rock crack will inevitably initialt and propagate under a load of KI,which is less than fracture toughness KIC but not less than a constant(marked as KIC2),KIC2 indicates the ability of rock to resist crack initiation and propagation under creep conditions and is less than fracture tough ness KIC.defined as creep fracture toughness in this paper,KIC2 should be considered as an importnat parameter on design and computation of rock engineering.The microstructureal mechanism for crack initiation and propagation of rock materials under creep condition was introduced based on competitive model between softening effect and hardening effect,and the validity of test result was explained.The test result was also verified in rheological theory.When KI is more than KIC2 but less than KIC,rock crack will initiate and propagate after a time interval of sustained loading under creep condition.In order to find the relation between duration of sustained lading.which can lead to crack initiation and propagation,and the initial stress intensity factor KI,an unequal0interval time sequence forecasting and predicting

  14. Further Clarifying Proximal Withdrawal States and the Turnover Criterion Space: Comment on Hom, Mitchell, Lee, and Griffeth (2012)

    Science.gov (United States)

    Maertz, Carl P., Jr.

    2012-01-01

    In "Reviewing Employee Turnover: Focusing on Proximal Withdrawal States and an Expanded Criterion," Hom, Mitchell, Lee, and Griffeth (2012) brought together many of the most important content and process factors in the employee turnover literature. In this paper, I attempt to clarify the true contributions of this framework for the turnover area…

  15. The Measurement of Executive Function at Age 3 Years: Psychometric Properties and Criterion Validity of a New Battery of Tasks

    Science.gov (United States)

    Willoughby, Michael T.; Blair, Clancy B.; Wirth, R. J.; Greenberg, Mark

    2010-01-01

    In this study, the authors examined the psychometric properties and criterion validity of a newly developed battery of tasks that were designed to assess executive function (EF) abilities in early childhood. The battery was included in the 36-month assessment of the Family Life Project (FLP), a prospective longitudinal study of 1,292 children…

  16. Interpretation of ongoing thermal response tests of vertical (BHE) borehole heat exchangers with predictive uncertainty based stopping criterion

    DEFF Research Database (Denmark)

    Poulsen, Søren Erbs; Alberdi Pagola, Maria

    2015-01-01

    A method for real-time interpretation of ongoing thermal response tests of vertical borehole heat exchangers is presented. The method utilizes a statistically based stopping criterion for ongoing tests. The study finds minimum testing times for synthetic and actual TRTs to be in the interval 12–2...

  17. Electronic Devices, Methods, and Computer Program Products for Selecting an Antenna Element Based on a Wireless Communication Performance Criterion

    DEFF Research Database (Denmark)

    2014-01-01

    A method of operating an electronic device includes providing a plurality of antenna elements, evaluating a wireless communication performance criterion to obtain a performance evaluation, and assigning a first one of the plurality of antenna elements to a main wireless signal reception and trans...

  18. da Vinci Skills Simulator for Assessing Learning Curve and Criterion-based Training of Robotic Basic Skills

    NARCIS (Netherlands)

    Brinkman, W.M.; Luursema, J.M.; Kengen, B.; Schout, B.M.; Witjes, J.A.; Bekkers, R.L.M.

    2013-01-01

    OBJECTIVE: To answer 2 research questions: what are the learning curve patterns of novices on the da Vinci skills simulator parameters and what parameters are appropriate for criterion-based robotic training. MATERIALS AND METHODS: A total of 17 novices completed 2 simulator sessions within 3 days.

  19. Membrane-bending constitutive law and perforation criterion for the analysis of reinforced concrete plate structures under soft impact

    International Nuclear Information System (INIS)

    In order to study the protection offered by reinforced concrete shell structures against soft projectiles impacts, we need first to characterize that kind of impact. In this document, we propose a new unified classification of shocks, allowing to distinguish soft and hard impacts. We show that aircraft crash, like every soft impact, produces bending and shear waves, which generate global and local damage: concrete cracking and reinforcement yielding in the whole structure, and possible perforation with a yield cone in the impact area. To model these phenomena we propose two computational tools. The first one is a membrane-bending non linear constitutive law for reinforced concrete slabs. This global model, using resultant variables, can simulate concrete cracking through damage theory and inelastic strains through plasticity theory. The Johansen bending yield criterion is improved to account for membrane effects. This material law has been implemented in Europlexus, an industrial finite element software for fast dynamics, and validated by comparison with experimental tests and other computational models. The second simulation tool is a perforation criterion for reinforced concrete slabs. It is a static criterion depending on bending moment, normal force, and shear force, and derived using limit analysis. We prove that it is possible to predict perforation in case of soft impact, applying this criterion on stress resultant variables coming from a dynamic computation. (author)

  20. Interpretation of ongoing thermal response tests of vertical (BHE) borehole heat exchangers with predictive uncertainty based stopping criterion

    DEFF Research Database (Denmark)

    Poulsen, Søren Erbs; Alberdi Pagola, Maria

    2015-01-01

    A method for real-time interpretation of ongoing thermal response tests of vertical borehole heat exchangers is presented. The method utilizes a statistically based stopping criterion for ongoing tests. The study finds minimum testing times for synthetic and actual TRTs to be in the interval 12...