The weakening of steam boilers by cutting holes in the shell for domes and necks     

W. Barnet Le Van 《Journal of The Franklin Institute》1880,110(5):313-323

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Dust showers     

Washington Jones  W Barnet Le Van  Tinius Olsen  William M Henderson  Wm.D Marks 《Journal of The Franklin Institute》1880,110(2):106-114

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The bourdon pressure gauge     

John D. Van Buren 《Journal of The Franklin Institute》1866,81(4):219-223

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Experiment station of the Bureau of Mines     

Van H. Manning 《Journal of The Franklin Institute》1920,189(2):251-252

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The relationship between peak height velocity and physical performance in youth soccer players   总被引：1，自引：1，他引：0  

Philippaerts RM  Vaeyens R  Janssens M  Van Renterghem B  Matthys D  Craen R  Bourgois J  Vrijens J  Beunen G  Malina RM 《Journal of sports sciences》2006,24(3):221-230

Longitudinal changes in height, weight and physical performance were studied in 33 Flemish male youth soccer players from the Ghent Youth Soccer Project. The players' ages at the start of the study ranged from 10.4 to 13.7 years, with a mean age of 12.2 +/- 0.7 years. Longitudinal changes were studied over a 5 year period. Peak height velocity and peak weight velocity were determined using non-smoothed polynomials. The estimations of peak height velocity, peak weight velocity and age at peak height velocity were 9.7 +/- 1.5 cm x year-1, 8.4 +/- 3.0 kg x year-1 and 13.8 +/- 0.8 years, respectively. Peak weight velocity occurred, on average, at the same age as peak height velocity. Balance, speed of limb movement, trunk strength, upper-body muscular endurance, explosive strength, running speed and agility, cardiorespiratory endurance and anaerobic capacity showed peak development at peak height velocity. A plateau in the velocity curves was observed after peak height velocity for upper-body muscular endurance, explosive strength and running speed. Flexibility exhibited peak development during the tear after peak height velocity. Trainers and coaches should be aware of the individual characteristics of the adolescent growth spurt and the training load should also be individualized at this time.  相似文献   

Three-axis platform simulation: Bond graph and Lagrangian approach     

M.J.L. Tiernego  J.J. Van Dixhoorn 《Journal of The Franklin Institute》1979,308(3):185-204

A bond graph model is derived for the geometric constraints of a three-axis flight table. Gimbal dynamics are easily added even in asymmetrical and unbalanced cases. A method is introduced to make the local dependent inertias computable. The bond graph compares favourably to the Lagrangian approach as to modelling effort and accessibility of intermediate variables as well as having computational advantages.  相似文献   

The Interplay of Psychology and Mathematics Education: From the Attraction of Psychology to the Discovery of the Social     

Karen François  Kathleen Coessens  Jean Paul Van Bendegem 《Journal of Philosophy of Education》2012,46(3):370-385

It is a rather safe statement to claim that the social dimensions of the scientific process are accepted in a fair share of studies in the philosophy of science. It is a somewhat safe statement to claim that the social dimensions are now seen as an essential element in the understanding of what human cognition is and how it functions. But it would be a rather unsafe statement to claim that the social is fully accepted in the philosophy of mathematics. And we are not quite sure what kind of statement it is to claim that the social dimensions in theories of mathematics education are becoming more prominent, compared to the psychological dimensions. In our contribution we will focus, after a brief presentation of the above claims, on this particular domain to understand the successes and failures of the development of theories of mathematics education that focus on the social and not primarily on the psychological.  相似文献   

The challenge to make schools safe: Preparing education personnel to curb student aggression and violence     

Robert A. Gable  Richard Van Acker 《The Teacher Educator》2013,48(3):1-18

Abstract

The incidence of aggression and violence in schools is approaching epidemic proportions. Unfortunately, few teacher education programs offer coursework designed to prepare school personnel to face the mounting challenge of student aggression. Drawing upon the accumulated literature, changes are discussed in the content of teacher education programs that would prepare teachers to effectively address student violence. Assertions are made that colleges of education must assume leadership roles in redefining professional boundaries to prepare all school personnel to combat student aggression. Lastly, arguments are presented for strengthening university and public school collaboration to promote programs designed to curb the rising tide of student aggression and violence.  相似文献   

Application of the Levenshtein Distance Metric for the Construction of Longitudinal Data Files     

Harold C. Doran  Paul B. Van Wamelen 《Educational Measurement》2010,29(2):13-23

The analysis of longitudinal data in education is becoming more prevalent given the nature of testing systems constructed for No Child Left Behind Act (NCLB). However, constructing the longitudinal data files remains a significant challenge. Students move into new schools, but in many cases the unique identifiers (ID) that should remain constant for each student change. As a result, different students frequently share the same ID, and merging records for an ID that is erroneously assigned to different students clearly becomes problematic. In small data sets, quality assurance of the merge can proceed through human reviews of the data to ensure all merged records are properly joined. However, in data sets with hundreds of thousands of cases, quality assurance via human review is impossible. While the record linkage literature has many applications in other disciplines, the educational measurement literature lacks details of formal protocols that can be used for quality assurance procedures for longitudinal data files. This article presents an empirical quality assurance procedure that may be used to verify the integrity of the merges performed for longitudinal analysis. We also discuss possible extensions that would permit merges to occur even when unique identifiers are not available.  相似文献   

The validity and reliability of focus groups as a research method in adult education     

N. E. Chioncel  R.G.W. Van Der Veen  D. Wildemeersch  P. Jarvis 《International Journal of Lifelong Education》2013,32(5):495-517

The article examines the theory and practice of focus groups in adult education research. Three theoretical positions are described: radical hermeneutic, moderate interpretative and pragmatic realistic position trying to bridge the gap with positivist research. This last position has been chosen as the departure point for a further analysis of the focus group elements, which relate to validity and reliability. The research examines four European research projects in the field of adult education. The most important and surprising data are presented with reference to both socio-psychological and technical problems in the use of this method. The results highlight the importance and dynamics of all the elements discussed.  相似文献