对称三对角矩阵的QL方法论

QL(QR) method is an efficient method to find eigenvalues of a matrix. Especially we use QL(QR) method to find eigenvalues of a symmetric tridiagonal matrix. In this case it only costs O( n^2) flops, to find all eigenvalues. So it is one of the most efficient method for symmetric tridiagonal matrices. Many experts have researched it. Even the method is mature, it still has many problems need to be researched. We put forward five problems here. They are: (1) Convergence and convergence rate; (2) The convergence of diagonal elements; (3) Shift designed to produce the eigenvalues in monotone order; (4) QL algorithm with multi-shift; (5) Error bound. We intoduce our works on these problems, some of them were published and some are new.     

The World Bank,support for universities,and asymmetrical power relations in international development

This article examines the role of the World Bank in advancing higher education sectors in the developing world, considering in particular the increasing power and strength of a global knowledge-based economy. Given the powerful role that intergovernmental organizations such as the World Bank play in shaping global economic policies, the authors are concerned about how the Bank’s policies and actions may limit knowledge generation and capacity building of universities in the developing world. Relatedly, the authors use case studies of the Bank’s involvement in Thailand and Uganda to better understand the role it plays in producing and reproducing forms of global hegemony. The authors discuss hegemony in terms of neocolonialism and neoliberalism. Neocolonialism is described as forms of domination advanced by powerful nations and their institutions, while neoliberalism is understood as an economic ideology by which weaker nations may be brought into greater alignment with global trade initiatives.     

Three-dimensional kinematic analysis of the golf swing using instantaneous screw axis theory,Part 2: golf swing kinematic sequence

A number of recent studies have measured the extent and timing of segment rotation during the golf swing. A promising technique, instantaneous screw axis (ISA) theory, could provide a better expression of segment rotation. In Part 1 of this two-part study, the objectives are to identify the ISA of the pelvis, shoulders and left arm during the downswing, compute segment angular velocity relative to that segment’s ISA and verify that ISA theory is a valid tool to analyse segment rotation during the golf swing. Results indicate that for all subjects, at least 71% of marker velocity is a result of rotation about their respective ISA, when averaging results over the duration of the downswing, confirming that motion is primarily rotational. Furthermore, ISA position and orientation of each segment approaches, on average, the expected gross axis of rotation, confirming that motion about the ISA is representative of joint motion.     

Higher education and the achievement (and/or prevention) of equity and social justice

The article examines the theoretical and empirical literature on higher education’s role in relation to social equity and related notions of citizenship, social justice, social cohesion and meritocracy. It considers both the education and the research functions of higher education and how these impact upon different sections of society, on who benefits and who loses from them. Questions for future research on the wider impact of higher education are posed as well as some research questions on the narrower issue of widening participation.     

Einstellungen von Sportlehramtsstudierenden zur Sprachbildung im Sportunterricht

An assessment of attitudes toward language awareness in physical education classes offers the possibility to evaluate learning and teaching opportunities related to this topic offered at universities. However, valid research instruments for this undertaking are currently lacking. The present article reports on the development and validation of a questionnaire for assessing attitudes toward language awareness in sports classes (“Erfassung von Einstellungen zur Sprachbildung im Sportunterricht,” ESBiS). A validation study of the ESBiS included N?=?254 student physical education teachers, 37.8% female, mean age 22.16 years, standard deviation 2.74 years. Explorative factor analysis identified a five-factor structure with the ESBiS factors linguistic goal and performance transparency, promotion of writing, language-corrective feedback, use of scaffolding, and advancement of technical vocabulary. The analyses indicate good factorial validity and reliability of the individual scales. The ESBiS factors can be satisfactorily modelled using confirmatory factor analyses. The ESBiS instrument thus demonstrates good psychometric quality. Furthermore, in some instances, very low positive correlations of the ESBiS factors with the validation criterion of multicultural attitudes could be shown. Additionally, correlation analyses with individual characteristics of the student physical education teachers showed that the developed instrument has sensitivity and discriminatory ability.     

Student trajectories in physics: the need for analysis through a socio-cultural lens

An analysis of student connections through time and space relative to the core discipline of physics is attempted, as viewed through the lens of actor-network-theory, by Antonia Candela. Using lenses of cultural realities, networks, and perceived power in the discourse of one specific university in the capital city of Mexico and one undergraduate physics classroom, the trajectories and itineraries of students are analyzed, relative to a physics professor’s pedagogical practices. This ethnographic study then yields comparisons between Mexican undergraduate students and students from the United States. Actor network theory recognizes that the symbiotic relationship existing between an actor and a continuum of space and time is defined by the symbiotic yet interdependent relationships and networks of practice (Lemke in Downward causation: Minds, bodies, and matter 2000). As part of this study and in line with actor-network-theory, human actors and non-human participants were viewed in relation to how subjects acted and were acted upon within networks of practice. Through this forum I reflect on this work with particular focus on the issues of situatedness of actors from a sociocultural perspective and how established networks viewed within this perspective frame and subsequently impact student trajectories and itineraries. In essence I argue for a need to look at a myriad of further complexities driving the symbiotic relationships being analyzed.     

“Sense of place” and college placement

It is generally assumed that young people with lower socioeconomic status (SES) face restricted access to higher education institutions, and particularly to those which are considered to be more prestigious. Differences in student placement in higher education institutions by place of residence are usually explained by their SES. We argue that place of residence is not only a geographical attribute, but also a social factor that influences self-identity and plays a significant role in student placement regardless of their SES. The study was conducted in Israel among first year undergraduate students, and analyzed the effect of living in four residential locality types (cities, small towns, Jewish and Arab villages) on institutional placement. The study focused on the patterns of student placement in institutions, controlling for individual SES and previous academic ability. Findings indicate that place of residence has a net effect on student placement, and it interacts with SES and with previous academic achievements. Less “successful” students, regardless of their SES, are less influenced by their residential locality. These differences in college placement are explained in part by the place of residence, which represents a way of life that creates a shared “sense of place” or “habitus” based on locality.     

A simple model for the hysteretic elastic shear modulus of unsaturated soils

Considering the great importance of the elastic shear modulus G₀ of unsaturated soils to the serviceability of many geo-structures in geo-energy and geo-environmental engineering, some semi-empirical models have been reported for the G₀ of unsaturated soils. Existing models require at least three parameters and the calibration of the model parameters requires extensive time-consuming unsaturated soil tests. In this study, a simple semi-empirical model is proposed for the hysteretic G₀ of unsaturated soils, requiring only two parameters. The constitutive variables of the mean Bishop’s stress and a bonding variable are adopted for considering the average stress between soil particles and the additional normal forces between soil particles provided by water menisci. The derived equation is applied to simulate the G₀ of unsaturated silts and sands. Comparisons between the measured and calculated results demonstrate that the proposed equation is able to describe the influences of various factors on G₀, including mean net stress, suction, wetting-drying, and void ratio.