Why some pool shots are more difficult than others     

Justin Jankunas  Richard N. Zare 《Resonance》2014,19(2):116-122

The physics behind the game of billiards is rather well understood as is our grasp of classical mechanics. We present here a mathematical explanation of why slice shots are more difficult than direct shots. Despite a large number of treatises dedicated to the study of physics of billiards, it appears that the simple explanation has escaped our attention until now. We show that high impact-parameter shots impart a larger angular spread to the object ball, compared to head-on shots. The effect can be understood in terms of a non-linear relationship between the impact parameter and the scattering angle, and the fact that a real-world pool player does not have a perfect cue ball control; in other words, the impact parameter distribution is not a delta function, but has a finite spread. To keep the mathematics simple and not to obscure the underlying physical principles our treatment ignores the ball’s spin, friction, and other well-known effects in the game of pool.  相似文献   

A New Twist on Studying the Development of Dynamic Spatial Transformations: Mental Paper Folding in Young Children     

Justin Harris  Nora S. Newcombe  Kathy Hirsh‐Pasek 《Mind, Brain, and Education》2013,7(1):49-55

The relation of spatial skills to academic success in areas such as math and science has sparked discussion in early education around how spatial thinking skills might be included in early schooling. Planning and evaluating new curricula or interventions requires understanding these skills and having the means to assess them. Prior developmental research focused primarily on one aspect of dynamic spatial transformations (DST), namely mental rotation. This study broadens our knowledge by addressing another important DST, namely mental folding. We devised a new test suitable for young children. Performance of 180 children between 4 and 7 years suggests that mental folding appears at around 5.5 years of age, although there were also marked individual differences. These data on the emergence of DST suggest that educational programs targeting this skill could start in preschool or kindergarten and provide a means to assess the effectiveness of such efforts.  相似文献   

Reference Works     

Darlene Myers  Margaret S. Jennings  Jane F. Spivack 《Communication Booknotes Quarterly》2013,44(6):58-59

COMPUTER SCIENCE RESOURCES: A GUIDE TO PROFESSIONAL LITERATURE, compiled and edited by Darlene Myers (White Plains, New York: Knowledge Industry Publications, 1981—$59.50, paper).

LIBRARY AND REFERENCE FACILITIES IN THE AREA OF THE DISTRICT OF COLUMBIA, edited by Margaret S. Jennings (White Plains, New York: Knowledge Industry Publications, 1983—$39.00, paper).

STATISTICAL SERVICES DIRECTORY: A GUIDE TO THE ORGANIZATIONS, CORPORATIONS, PROFESSIONAL AND TRADE ASSOCIATIONS, RESEARCH CENTERS, UNIVERSITIES, PUBLISHERS, FOUNDATIONS, AND GOVERNMENT AGENCIES THAT PROVIDE STATISTICAL SERVICES (Detroit, Michigan: Gale Research Company, 1984—$150).

CAREERS IN INFORMATION, edited by Jane F. Spivack (White Plains, New York: Knowledge Industries Publications, 1982—$34.50/27.50).

VIDEOTEX: A SELECTED BIBLIOGRAPHY, Volume 1, 1979-1982 (Technical and Education Center of the Graphic Arts, Rochester Institute of Technology, P.O. Box 9887, Rochester, New York—price not given, but about $15.00, paper).

TELEMANAGEMENT NEWS SERVICE: THE NEWS SERVICE ON THE TELEPHONE INDUSTRY FOR OFFICE, DP AND COMMUNICATIONS MANAGEMENT (SRG Publications, P.O. Box 335, Palmyra, New Jersey 08065—$260.00 per year/weekly).

SPACE ENTERPRISE TODAY: THE NEWSLETTER ON COMMERCIAL SPACE VENTURES (Phillips Publishing Inc., 7315 Wisconsin Avenue, Suite 1200 N, Bethesda, Maryland 20814—$297.00 per year/monthly).

LINK-UP: COMMUNICATIONS AND THE SMALL COMPUTER (On-Line Communications, Inc., 3938 Meadowbrook Road, Minneapolis, Minnesota 55426-$23.95 per year/monthly).

RESEARCH NOTES (Policy Development and Planning, Corporation for Public Broadcasting, 1111 Sixteenth Street, N. W., Washington, D.C. 20036—apparently free on request/irregular).

SCA: RADIO SUBCARRIER REPORT (Waters & Company, Security Mutual Building, Suite 322, Binghampton, New York 13901—$185.00 per year/monthly).  相似文献   

The Impact of Subjective Camera in Sports on Arousal and Enjoyment     

R. Glenn Cummins  Justin R. Keene  Brandon H. Nutting 《Mass Communication and Society》2013,16(1):74-97

Although scholars have generated much research examining enjoyment of mediated sports, much of it has failed to explore how visual production elements shape viewer response. This study examines the impact of one increasingly common technique, subjective camera, on viewer arousal and enjoyment of game play. Participants viewed multiple plays from a college football game that varied in excitatory potential as well as viewing angle. Game play viewed via subjective camera elicited a greater sense of presence in the mediated environment and elicited more frequent arousal responses compared to traditional sideline perspectives of game play. However, the impact of viewing angle on enjoyment as well as self-reported arousal was dependent upon the exciting or dull nature of game play. Invoking the dynamics of excitation transfer theory, we discuss the potential explanations for this relationship as well as its implications for sports broadcasters.  相似文献   

The relationship between student communication motives and perceived instructor communicator style   总被引：1，自引：0，他引：1  

Scott A. Myers  Timothy P. Mottet  Matthew M. Martin 《Communication Research Reports》2013,30(2):161-170

The purpose of this study was to examine the relationship between student communication motives (i.e., relational, functional, participatory, excuse‐making, sycophantic) and perceived instructor communicator style (i.e., friendly, impression leaving, relaxed, contentious, attentive, precise, animated, dramatic, open, dominant). Participants were 228 undergraduate students enrolled in a variety of communication courses at a small Midwestern university. Results indicate that (a) the perceived instructor communicator style attributes of impression leaving, friendly, and contentious predict student use of the relational motive, (b) the attribute of friendly predicts student use of the functional motive, (c) the attributes of animated, contentious, and friendly predict student use of the participatory motive, (d) the attributes of attentive and contentious predict student use of the excuse‐making motive, and (e) the attributes of contentious and friendly predict student use of the sycophantic motive.  相似文献   

Relational messages in conflict situations among siblings     

Donna R. Pawlowski  Scott A. Myers  Kelly A. Rocca 《Communication Research Reports》2013,30(3):271-277

The purpose of this study was to explore the association of sibling conflict style (i.e., integrative, distributive, avoidant) with perceived relational communication themes (i.e., immediacy, similarity, receptivity, composure, formality, dominance, equality, task orientation). Participants were 186 undergraduate students who reported on a recent conflict episode with a sibling. Results indicate that (a) siblings who used the relational communication themes of immediacy, similarity, receptivity, composure, and equality reported using the integrative conflict strategy, but not the distributive conflict strategy, and (b) siblings who used the relational communication theme of immediacy and to a lesser extent the theme of task orientation, but not the relational communication themes of similarity and equality, reported not using the avoidant conflict strategy.  相似文献   

Sibling communication satisfaction as a function of interpersonal solidarity,individualized trust,and self‐disclosure     

Scott A. Myers 《Communication Research Reports》2013,30(3):309-317

The purpose of this study was to examine sibling communication satisfaction, with a specific focus on interpersonal solidarity, individualized trust, and self‐disclosure. Respondents (N = 360) were asked to report on a relationship with either an older sister, younger sister, older brother, or younger brother. Results indicate that interpersonal solidarity is the largest predictor of sibling communication satisfaction, followed by individualized trust, and self‐disclosure.  相似文献   

The relationship between perceived instructor communicator style,argumentativeness, and verbal aggressiveness     

Scott A. Myers  Kelly A. Rocca 《Communication Research Reports》2013,30(1):1-12

The purpose of this study was to examine the interrelationships among perceived instructor communicator style, perceived instructor trait argumentativeness, and perceived instructor trait verbal aggressiveness in the college classroom. Participants were 236 undergraduate students enrolled in a variety of communication courses at a large Eastern university. Results indicated that (a) perceived instructor trait argumentativeness was positively related to the perceived instructor communicator style attributes of impression leaving, contentious, open, dramatic, dominant, precise, relaxed, attentive, and animated; (b) perceived instructor trait verbal aggressiveness was positively related to the perceived instructor communicator style attributes of contentious and precise, and negatively related to the perceived communicator style attributes of impression leaving, relaxed, friendly, attentive, and animated; and (c) perceived instructor use of verbally aggressive messages was related in some way to the perceived instructor communicator style attributes of contentious, impression leaving, friendly, attentive, animated, relaxed, dramatic, and precise.  相似文献   

Understanding MOOCs as an Emerging Online Learning Tool: Perspectives From the Students     

Min Liu  Jina Kang  Mengwen Cao  Mihyun Lim  Yujung Ko  Ryan Myers 《The American journal of distance education》2013,27(3):147-159

This study examined participants’ learning experiences in the context of a six-week massive open online course (MOOC) in journalism with five thousand students from 137 countries. Three research questions were asked: (1) Who are the students and why are they enrolled in this MOOC?, (2) How much time have the students spent in taking this MOOC and have they completed all the assignments?, and, (3) What have they learned and what aspects of this MOOC do the students find most helpful? Four hundred and nine students responded to a survey and forty-four responded to interview questions. The main findings showed 84% of the participants were working professionals and only 28.9% were from a journalism background. Of those who did not complete the course, lack of time was the top reason. Most participants reported a positive learning experience, but lack of feedback and/or poor quality were reported as negative experiences. The discussion forum was the least liked aspect of the course.  相似文献   

Comparing Results from the Clinical Assessment of Behavior and Child Behavior Checklist with Referred Preschoolers     

Carl L. Myers 《Psychology in the schools》2013,50(1):1-12

Behavior rating scales are popular assessment tools but more research is needed on the preschool versions of the instruments, particularly with referred samples of preschoolers. This study examined the comparability of results from parent ratings on the preschool versions of the Child Behavior Checklist (CBCL/1.5‐5, Achenbach & Rescorla, 2000) and the Clinical Assessment of Behavior‐Parent form (CAB‐P, Bracken & Keith, 2004) with 74 clinically referred preschoolers. While pairs of similarly named scales from the two instruments received significant correlations, mean scores from the CBCL/1.5‐5 were significantly higher than those from the CAB‐P. Classification consistency was a concern as well. School psychologists are urged to be cautious in their interpretation of results from preschool behavior rating scales.  相似文献