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101.
The aim of the study was to examine the pattern of the change in discomfort for combined wrist deviation and forearm rotation as joint angles increased away from neutral in a repetitive task. There were five levels of wrist deviation (neutral, 35% and 55% of the range of motion (ROM) in radial and ulnar deviation) and five levels of forearm rotation (neutral, 30% and 60% of the ROM in pronation and supination). Twenty-five participants performed a repetitive flexion task with a force of 10 N +/- 1 N at a frequency of 15 exertions per min, with replication after 1 week for six of the participants. A visual analogue scale was used for recording the discomfort scores. Repeated measures analysis of covariance with the Greenhouse-Geisser correction, where necessary, was used on transformed values of the discomfort scores. Grip test endurance time at 50% of maximum voluntary contraction was included as a covariate. Wrist deviation (p = 0.007) and forearm rotation (p = 0.001) were found to have significant effects. Interactions of the main factors were not significant and nor was the covariate. Quadratic regression equations were derived and were used to generate iso-discomfort contours, which show a useful area of low discomfort around the central neutral zone of wrist postures, but with steep increases in discomfort at the extreme combinations of wrist ulnar/radial deviation with forearm pronation/supination. Discomfort equations and contours, showing wrist and forearm postures, which are either acceptable or potentially injurious, are useful for the design of industrial tools, machine controls and workspaces. Reference to these can help to reduce the risk of musculoskeletal injury associated with the tasks or tools by avoiding poor postures with unacceptable deviations from neutral posture. 相似文献
102.
During the period 1970-80, there were reported 146 cases of in-flight sudden incapacitation in the USAF. Of these, 62 involved pilots, 14 were navigators, and 70 were student pilots. The etiologies of sudden incapacitation included illness without loss of consciousness, loss of consciousness, spatial disorientation, and improper M-1 maneuver. Each of these categories is analyzed with emphasis upon prevention, for example, not flying with symptomatic preexisting disease, continued emphasis upon spatial disorientation training, and correct performance of the M-1 maneuver. Based upon the data, conclusions and recommendations are suggested to minimize the risk of episodes of in-flight sudden incapacitation. 相似文献
103.
Ossip-Klein Deborah J.; Epstein Leonard H.; Winter M. Kathleen; Stiller Richard; Russell Peggy; Dickson Barb 《Canadian Metallurgical Quarterly》1983,51(2):234
Assessed the effects of changing to low tar/nicotine/carbon-monoxide-(CO)-yield cigarettes on alveolar carbon monoxide over a 5–6 wk period for 40 adult chronic smokers of high tar/nicotine/CO cigarettes. Ss were assigned to either a 5-wk step-wise brand-reduction treatment or to a delayed-treatment control group. Ss were assessed for (a) resting CO body burden and CO uptake per cigarette and (b) smoking topography and rate. Although CO uptake was significantly lower after Ss smoked low tar/nicotine/CO cigarettes than after smoking their original brand, resting CO body burden did not change. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
Eron Leonard D.; Huesmann L. Rowell; Brice Patrick; Fischer Paulette; Mermelstein Rebecca 《Canadian Metallurgical Quarterly》1983,19(1):71
Conducted a 3-yr longitudinal study with 2 large samples of elementary school youngsters overlapping in 1 grade (N?=?672, 607, and 505 for each successive year). It was thus possible to trace developmental trends from Grades 1 to 5 on the following variables: aggression, frequency of TV viewing, extent of violence viewed on TV, judged realism of TV programs, and preference for masculine, feminine, or neutral activities. Data support the theory that there is a sensitive period during which the effect of TV can be especially influential on children's behavior. Further, since the correlation between violence viewing and aggression tends to increase until age 10–21 yrs, a cumulative effect beyond the sensitive period is suggested. (11 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
105.
Studied phonological coding in printed-word recognition in English by examining the use made of syllable information by skilled and less skilled readers in 2 experiments using 32 2nd graders and 81 undergraduates. Stimuli were bisyllabic frequent nouns. Syllable coding was used by the less-skilled 2nd graders but not by either the better 2nd graders or adults in lexical decision tasks. However, adults did make use of syllable information when the direct use of letter information was slowed by presenting items in alternating upper- and lowercase letters. Differences between children and adults in their use of the syllable information in pseudowords are interpreted as indicating that for skilled adult readers, the major focus of activity in word recognition is at the letter level. For immature readers, the process of word recognition is less analytic and involves a more extensive lexical search based on a reduced amount of letter information. The results are discussed in terms of an interactive model of reading. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
106.
This bibliography compiles references from 1970 to 1982 on ethical and legal issues in various areas of therapeutic practice. The 162 references are intended to provide resources to the practitioner that are easily accessible in the published literature. Works deal with child therapy, marital and family therapy, group therapy, behavior therapy, community work, forensic work, and testing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
107.
Derek A. Paley Naomi Ehrich Leonard Rodolphe Sepulchre 《Systems & Control Letters》2008,57(3):209-215
We provide a cooperative control algorithm to stabilize symmetric formations to motion around closed curves suitable for mobile sensor networks. This work extends previous results for stabilization of symmetric circular formations. We study a planar particle model with decentralized steering control subject to limited communication. Because of their unique spectral properties, the Laplacian matrices of circulant graphs play a key role. We illustrate the result for a skewed superellipse, which is a type of curve that includes circles, ellipses, and rounded parallelograms. 相似文献
108.
Processes of ethical decision-making are thought to depend on the issue faced when making the decision. We examined the processes by examining student's reactions to five scenarios involving IT use. Data were collected using a questionnaire following a group discussion. The results showed that ethical decision-making processes did indeed vary by scenario, suggesting that a single-issue approach is inadequate for studying ethical decision-making. Perceived importance of the ethical issue was a factor in the scenarios, but it did not have an all-inclusive influence on the decision-making of the participants. The results were considered in the context of theories and Mason's ethical issues of the information age. We offer advice to managers on how to limit unethical behavior. 相似文献
109.
Leonard Gallagher Jeff Offutt Anthony Cincotta 《Software Testing, Verification and Reliability》2006,16(4):215-266
In object‐oriented terms, one of the goals of integration testing is to ensure that messages from objects in one class or component are sent and received in the proper order and have the intended effect on the state of the objects that receive the messages. This research extends an existing single‐class testing technique to integration testing of multiple classes. The single‐class technique models the behaviour of a single class as a finite state machine, transforms the representation into a data flow graph that explicitly identifies the definitions and uses of each state variable of the class, and then applies conventional data flow testing to produce test case specifications that can be used to test the class. This paper extends those ideas to inter‐class testing by developing flow graphs, finding paths between pairs of definitions and uses, detecting some infeasible paths and automatically generating tests for an arbitrary number of classes and components. It introduces flexible representations for message sending and receiving among objects and allows concurrency among any or all classes and components. Data flow graphs are stored in a relational database and database queries are used to gather def‐use information. This approach is conceptually simple, mathematically precise, quite powerful and general enough to be used for traditional data flow analysis. This testing approach relies on finite state machines, database modelling and processing techniques and algorithms for analysis and traversal of directed graphs. The paper presents empirical results of the approach applied to an automotive system. This work was prepared by U.S. Government employees as part of their official duties and is, therefore, a work of the U.S. Government and not subject to copyright. Published in 2006 by John Wiley & Sons, Ltd. 相似文献
110.
Leonard E. Schwer 《Engineering with Computers》2007,23(4):295-309
The quantified comparison of transient response results are useful to analysts as they seek to improve and evaluate numerical
models. Traditionally, comparisons of time histories on a graph have been used to make subjective engineering judgments as
to how well the histories agree or disagree. Recently, there has been an interest in quantifying such comparisons with the
intent of minimizing the subjectivity, while still maintaining a correlation with expert opinion. This increased interest
has arisen from the evolving formalism of validation assessment where experimental and computational results are compared
to assess computational model accuracy. The computable measures that quantify these comparisons are usually referred to as
validation metrics. In the present work, two recently developed metrics are presented, and their wave form comparative quantification
is demonstrated through application to analytical wave forms, measured and computed free-field velocity histories, and comparison
with Subject Matter Expert opinion.
相似文献
Leonard E. SchwerEmail: |