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51.
Construction accidents are broadly categorized into five basic groups, namely falls (from elevation), shock (electrical), caught in/between, struck-by, and other. “Struck-by” accidents accounted for 22% of all construction-related fatalities recorded by the Occupational Safety and Health Administration between 1985 and 1989. Recent (1997 to 2000) data show that the percentage of struck-by accidents constituted 24.6% of the fatalities and serious construction worker injuries. Struck-by accidents primarily involve workers struck by equipment, private vehicles, falling materials, vertically hoisted materials, horizontally transported materials, and trench cave ins. Determining possible causation factors of these accident types is often difficult, due to the broad categories utilized in the accident coding system. This study resulted in gaining insights about the root causes of the struck-by injuries. By finding the root causes, effective methods for accident prevention can be developed.  相似文献   
52.
This article had 2 aims: (a) to comprehensively review and synthesize the literature on predictors of health service utilization in survivors of traumatic events and posttraumatic stress disorder (PTSD) patients and (b) to discuss methodological issues in examining service utilization in this population. PsycINFO was searched for relevant articles published through April 2004. Included studies had to primarily sample trauma survivors or PTSD patients and statistically explore health service use determinants. Although some findings conflicted across studies, increased mental health service use was generally related to being female, having a previous trauma history, and having a PTSD diagnosis. Increased medical service use was found among those with a PTSD diagnosis. Methodological recommendations are made for future health service use studies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
53.
Questions are often raised regarding the effectiveness and value of treatment programs for children and families. Recently, programs have been increasingly held accountable for services offered. In response, the member agencies of IARCCA have developed a comprehensive outcome measurement program. This article describes the project, focusing on the conditions that led to its inception and how the measurement plan was developed. In addition, the article includes information on the selection of personnel, measurement instruments, and methods and on the process of data collection. Summary results are provided, including how these results are utilized to improve services. Finally, the continued expansion and future directions of the Outcome Project are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
54.
The goal of this research was to operationalize the information technology infrastructure (ITI) concept by identifying its underlying dimensions and establishing a valid and reliable measure for the construct. In order to accomplish this task with the highest degree of certainty, two approaches were sequentially applied: exploratory factor analysis and confirmatory factor analysis. In evaluating the confirmatory factor model, a step-by-step process was employed, assessing unidimensionality, reliability, discriminant validity, and nomological validity. The dimensions of ITI were determined to be: Chief Information Officer, IT Planning, IT Security, Technology Integration, Advisory Committee, Enterprise Model, and Data Administration. Researchers may now make use of this validated ITI measure to conduct investigations of ITI and other organizational measures. Implications of the ITI measure with other organizational initiatives such as electronic commerce and knowledge management are explored.  相似文献   
55.
This research investigates a new theoretical model for examining the relationships between user perceptions during innovation adoption. We have taken several innovation-related variables and constructed a framework for assessing the ability of a technology to improve worker performance. Prior research has not addressed the appropriate relationship between innovation adoption-related variables as applied to information systems development methodologies (SDM). This study attempts to use innovation-related variables created by Moore and Benbasat (Information Systems Research 2(3) (1991) 192–222) and Davis (MIS Quarterly 13(3) (1989) 319–340) to propose a framework useful by project managers in designing innovations that will successfully support the efforts of technology users. A framework is proposed, tested, and modified in the context of using an SDM to govern large systems development operation. Forty-seven users within a military software development organization were surveyed about their perceptions of a recently implemented structured SDM. A proposed model of innovation adoption perceptions was tested using correlation and partial least squares regression. Findings suggest a model for predicting the perceived relative advantage of SDMs in the adoption stage of their implementation which is useful in designing techniques in the IS development organizational function.  相似文献   
56.
The purpose of the current study was to examine in detail the association between witnessing domestic violence (DV) and long-term psychological adjustment. Important limitations of past research were addressed, including controlling for several associated risk factors. Special attention was paid to whether the perpetrator of the violence was the maternal or paternal figure, as well as to whether the witness to the violence was male or female. Participants completed measures examining DV witnessed, direct child abuse experienced, and current psychopathology. Following screening for physical and sexual abuse, a sample of 351 individuals was selected. Four groups of participants were compared. Results indicated that individuals who had witnessed either physical DV or major psychological DV had higher levels of psychopathology than individuals who reported witnessing minor psychological DV or controls. After controlling for direct psychological abuse experienced, witnessing DV remained a significant predictor of psychopathology for males but not for females. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
57.
This study investigated whether exposure to musical mood induction procedures (MMIP) differentially increases the strength of specific alcohol expectancies for coping motivated (CM) versus enhancement motivated (EM) drinkers. Participants were 86 undergraduates who had elevated scores on either the CM or EM subscale of the Drinking Motives Questionnaire (M. L. Cooper, 1994). Participants were randomly assigned to either a positive or negative mood condition. The Alcohol Craving Questionnaire (E. G. Singleton, S. T. Tiffany, & J. E. Henningfield, 1994) was administered at baseline and after MMIP to assess phasic changes in alcohol expectancy strength. Consistent with hypotheses, only CM drinkers in the negative mood condition reported increased relief expectancies, and only EM drinkers in the positive mood condition reported increased reward expectancies. Theoretical and clinical implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
58.
Abstract— We report on theoretical simulations and measurements of the optics of BiNem® displays, taking into account not only the luminance at normal incidence, but contrast ratio and color shift over the viewing hemisphere as well. Transmissive and reflective BiNem® modes were optimized differently, emphasizing contrast in transmission and paperlike, white appearance in reflection.  相似文献   
59.
A scintillator-based energetic ion loss detector has been successfully commissioned on the Alcator C-Mod tokamak. This probe is located just below the outer midplane, where it captures ions of energies up to 2 MeV resulting from ion cyclotron resonance heating. After passing through a collimating aperture, ions impact different regions of the scintillator according to their gyroradius (energy) and pitch angle. The probe geometry and installation location are determined based on modeling of expected lost ions. The resulting probe is compact and resembles a standard plasma facing tile. Four separate fiber optic cables view different regions of the scintillator to provide phase space resolution. Evolving loss levels are measured during ion cyclotron resonance heating, including variation dependent upon individual antennae.  相似文献   
60.
A new approximation technique is presented for solving nonlinear oscillation problems. A solution of form x = x0 sin ωt is assumed and put into the differential equation, which leads to an algebraic equation which can be solved for ω in terms of x0. The new technique is to reduce the algebraic equation to an identity at ωt = π/3. This method is compared with other common approximation techniques and with the exact solution for several nonlinear problems. Overall, the new method works better than any other approximation technique. In addition, it has the very practical advantage of being purely algebraic; no integrals need be evaluated, as in several other methods.  相似文献   
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