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891.
This study attempts to understand how achievement gap Discourse might be present in preservice teachers' (PSTs) Discourse about students they found challenging to teach. Using a Discourse analytic approach, the project considers: How do PSTs describe challenging students in their written reflections? Do PSTs draw on students' multiple identities? Findings reveal PSTs are taking up a Discourse prevalent in today's educational environment in which students, particularly ethnically and linguistically diverse students, are discussed in terms of inadequacy. PSTs typically describe students in terms of a single label, rather than as having multiple identities. Implications include that PSTs might enter teaching with a limited view and incomplete understanding of students and that even a teacher-education program aimed at pushing PSTs to question their assumptions about students might be reifying a systemwide Discourse that identifies students based on labels—sometimes deficit-oriented labels—rather than fuller understandings of students.  相似文献   
892.
This article addresses the problem of how opportunities to learn in teacher education programs influence future elementary mathematics teachers’ knowledge. This study used data collected for the Teacher Education and Development Study in Mathematics (TEDS-M). TEDS-M measured the mathematics content knowledge (MCK) and the mathematics pedagogical content knowledge (MPCK) of future teachers in their final year in teacher preparation programs. The purpose of this study is to explore whether elementary teaching candidates’ MCK and MPCK are associated with their opportunities to learn in mathematics courses and mathematics methods courses in five countries. The results showed that opportunities to learn in some teacher preparation components are more important than in other components.  相似文献   
893.
The compression index is a key parameter in the field of soft clay engineering. In this paper, we propose an improved method for correlating the compression index with the physical properties of intact Chinese marine clays that are involved in many construction projects in coastal regions in China. First, the compression index and some common physical properties of clays from 21 regions along the Chinese coast are extracted from the literature. Then, a basic regression analysis for the compression index using the natural water content and Atterberg limits is conducted. To improve the correlation performance, an evolutionary polynomial regression (EPR) and real coded genetic algorithm (RCGA) combined technique is adopted to formulate different equations involving different numbers of variables. An optimal correlation using only natural water content and liquid limit as input parameters is finally selected according to the root mean square error (RMSE), Akaike’s information criterion (AIC), and Bayesian information criterion (BIC). The proposed correlation is evaluated and shown to perform better than existing empirical correlations in predicting the compression index for all selected Chinese marine clays. This correlation is validated to be reliable and applicable to engineering applications through the prediction of the properties of an embankment on the southeast coast of China using finite element method. All comparisons show that the EPR and RCGA combined technique is powerful for correlating the compression index with the physical properties of the clay, and that model selection by RMSE, AIC, and BIC is effective. The proposed correlation could be used to update current formulations, and is applicable to engineering design in coastal regions of China.  相似文献   
894.
Considering the growth in research, examining the development of mainstream sport athletes over the past two decades, studies examining development of athletes with disabilities have been surprisingly limited. While similarities in developmental trajectories between the two cohorts may exist regarding factors such as the value of practice, which tend to be universal regardless of context, disability-related issues (e.g. whether the disability was congenital or acquired) may influence the course of development, affecting variables such as starting age, training and developmental milestones. Fifty-two male and female athletes training with the Wheelchair Basketball Canada National Academy provided detailed training histories. Athletes illustrated similar developmental patterns (e.g. milestones, training adjustments) as they progressed through their sporting career. However, athletes with congenital disabilities started participation in wheelchair basketball and unorganised practice at significantly younger ages (t49?=??4.35, p?<?.001, d =?1.32; t49?=??3.49, p?<?.001, d =?1.03, respectively). While athletes with congenital disabilities continued to reach a majority of the sporting milestones at younger ages, athletes with acquired disabilities were able to reach late career milestones (e.g. national debuts) at similar ages. Athletes’ disability severity did not influence their progress through the developmental milestones and time devoted to training throughout their sporting career. Future work may consider examining developmental trajectories and training histories of athletes in various parasports to extend our understanding of their development and skill acquisition.  相似文献   
895.
The article traces the origin and development of the concept of social skills in first and foremost American academic discourse. As soon as the concept of social skills was coined, the concern for people lacking such skills started and has been on the increase ever since (now sharing public attention with related concepts such as self-control, emotional intelligence and empathy). After the analysis of the academic history of the concept follows an examination of the implementation of a range of assessment instruments and training programmes related to social skills (and lack hereof) in contemporary Danish welfare institutions (more specifically, day nurseries and schools, employment and penal services). The analysis forwarded in the article thus demonstrates how an intellectual idea may develop and travel - and on its journey connect to pre-existing cultural logics and societal concerns. The idea of social skills has through its development been made uncontroversial – everybody wants to be skilful. The concept does, however, convey an individualistic view on social life and imposes a reflexivity over own performance on the participants. Further, its normative character contributes to a problematization of those who are perceived to lack these skills.  相似文献   
896.
Are the categories used to study the social world and acting on it “real” or “conventional”? An empirical answer to that question is given by an analysis of the debates about the “quality” of statistics produced by the European National Institues of statistics in the 1990s. Six criteria of quality were then specified: relevance, accuracy, timeliness, accessibility, comparability and coherence. How do statisticians and users of statistics deal with the tension produced by their objects being both “real” (they exist before their measurement) and “conventionally constructed” (they are in a way, created by these conventions)? In particular, the technical and sociological distinction between the criteria of relevance and accuracy implies a realistic interpretation, desired by users, but that is nonetheless problematic.  相似文献   
897.
Varda Langholz Leymore's Hidden Myth: Structure and Symbolism in Advertising (New York: Basic Books, 1975—$10.00).

John S. Wright and John E. Mertes's Advertising's Role ie Society. (St. Paul, Minn.: West Publishing Co., 1974—price not given, paper).

Allan M. Cartter's Ph.D's and the Academic Labor Market (New York: McGraw-Hill, 1976—$12.50).  相似文献   
898.
In this paper, decomposition methods for multidimensional data hypercubes of OLAP systems are investigated. Criteria for reducing the computational complexity of the decomposition methods are presented and comparisons are made with the traditional solutions of multidimensional data analysis problems. Examples illustrating the application of these criteria to investigating the dynamics of computational complexity changes for specific types of reduction problems are considered.  相似文献   
899.
900.
求解有约束最优化问题的不连续罚函数积分总极值法   总被引:1,自引:0,他引:1  
1IntroductionLetXbe a topological space ,Sa nonempty subsetofXandf:X→Ra real-valued function.Consider thefollowing constrained opti mization problem:c*=infx∈Sf(x) , (1)and the set of global mini mizers :H*={x∈S|f(x) =c*} (2)under the assumptions (see Refs .[1] and [2]) :(A) :fis lower semi-continuous ,Sis closed andthere is a real numberbsuch that the setHb={x∈S|f(x)≤b} is a nonempty compact set ;(R) :fis upper robust onS,i.e.,{x∈S|f(x) 相似文献   
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