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181.
Formal models for service composition have been proposed with the variation of the requirements of service developers. Some
famous models have provided checking and verification techniques and tools for the behavior of service composition. These
models generally focus much on the message flow of web services and neglecting the data contained in the exchanged messages
among services, which restrict the application range of these models and also the web service techniques. As new kind of services
with different protocols and communication methods have appeared, it is needed to model service composition from a new view
which is adapted to the new development in service area. In this paper we offer a function oriented model of service composition
which treats the composite service as a software system and specify the function of services which can be directly used to
the realization by service providers. 相似文献
182.
The author articulates key stressors in the lives of families who are homeless. These stresses often combine with barriers such as lack of job opportunities and/or insensitive professionals. Strategies for helping homeless families overcome these barriers and related issues are presented. 相似文献
183.
OBJECTIVE: This study examined specific aspects of child sexual abuse in relation to symptom severity among hospitalized patients diagnosed with bulimia nervosa. METHOD: Participants were 45 hospitalized bulimic women who reported a history of child sexual abuse. Structured interviews were conducted in order to obtain detailed information regarding specific features of the abusive event(s). Participants also completed instruments that measured depression and eating pathology. RESULTS: There were no significant differences in severity of depression or eating disturbance among women reporting differing abusive experiences including intrafamilial versus extrafamilial abuse, abuse with or without the use of physical force, one versus multiple incidents, early abuse versus abuse occurring after age 14, contact versus noncontact abuse, disclosed versus undisclosed, and combined physical/sexual abuse versus sexual abuse alone. CONCLUSION: The specific characteristics of child sexual abuse are not related to the level of symptomatology for hospitalized bulimic patients. This study suggests that differences in the nature of the abuse may not be as important as the fact that the abuse occurred in the first place. 相似文献
184.
JIŘI LAŽANSKÝ VLADIMÍR MAŘÍK OLGA ŠTĚPÁNKOVÁ 《European Journal of Engineering Education》1992,17(2):143-149
Both the origin and development of artificial intelligence (AI) are connected with the origin and development of computers. Computers play a very important role in engineering education. AI influences such disciplines like CAD, CASE, CAE, and others. The specific experience concerning AI education at a technical university has been gathered in this paper. There is stressed need of good balance between theoretical background and individual training with computers as well as importance of personal experience in solving practical AI. 相似文献
185.
Meta-analysis was used to review the results of 25 studies that compared the classroom behavior of children and adolescents with learning disabilities (LD) to children without learning disabilities. The data were analyzed from several different methodological perspectives. Results showed that both methodologically strong and weak studies demonstrated significant behavioral deficits of children with learning disabilities compared to their nondisabled peers in each of five overall areas: on-task behavior, off-task behavior, conduct disorders, distractibility, and shy/withdrawn behavior. Both observational and teacher rating data demonstrated these differences. Effect sizes for both groups of studies seemed to cluster around 1 standard deviation, suggesting noticeable and educationally significant impairment in the behavior of children with disabilities. Analysis of grade-level effect sizes suggests some explanation for the large number of referrals often witnessed during the elementary school years. Educational implications of these behavioral differences in terms of implications for mainstreaming are discussed. 相似文献
186.
The science achievement of 226 5th graders from districts that have a kit-based inquiry science curriculum supported by intensive
professional development (PD) is compared with data from a group of 173 5th graders from other districts that use nonkit science
materials and do not have systematic science PD for teachers. Within the kit-based project, the sample of project teachers
is stratified to select teachers with a high number of science PD hours versus those with few hours. While there were no significant
differences in the mean total scores for kit-based students with low PD versus high PD teachers, the kit-based classrooms
scored significantly higher than students in nonkit classrooms on both the pretest and posttest, though there were significantly
more minutes of science instruction in the nonkit classrooms. Finally, nonkit teachers taught more units of shorter length
and reported lower levels of preparedness to use reform pedagogical approaches. 相似文献
187.
In 1981, the career structure in Dutch higher education was modified in such a way that performance criteria, particularly possession of a doctorate and research and publication activity, were required for promotion. In particular, the hierarchy of university posts below that of full professor was modified in such a way that persons holding so‐called WHM(senior scientific staff level) positions were required to reapply for the new UHD(associate professor) positions on a competitive basis which stressed the publication record of candidates. Using a sampling of academic women drawn from the natural sciences, the authors offer an explanation as to why women academics did less well than men in the competitions for these new posts. Although the process did not discriminate against women as such, it did not favour academics on the periphery of the profession, where many women at the time found themselves. The situation identified was the result of social factors more than of institutional discrimination. Presently, younger women ‐graduate students ‐ are rapidly moving from the periphery of the profession to the centre. Active involvement in professional networks will aid academic women in their careers; however, over‐involvement in family matters (the care network) may be harmful to the career progress of academic women. 相似文献
188.
Pigeons' keypecking was reinforced by food on baseline schedules of multiple variable interval (VI) x VI x and on contrast schedules of multiple VI x VI y. Deprivation of food was varied by maintaining subjects at 75%, 85%, and 95% (+/- 2%) of their free-feeding weights. Positive and negative behavioral contrast were observed. The size of the contrast was not systematically altered by changes in deprivation. Positive and negative contrast were both larger later in the session than they were earlier. Within-session decreases in responding were steeper for the baseline than for the contrast schedules for positive contrast. Within-session decreases were steeper for the contrast than for the baseline schedules for negative contrast. These results were predicted by the idea that different amounts of habituation to the reinforcer during the baseline and contrast schedules contribute to behavioral contrast. The results show that contrast occurs under conditions that reduce the effect of the following component. The results support the assumption that positive and negative contrast are produced by symmetrical theoretical variables. 相似文献
189.
In five conditioned taste aversion experiments with rats, summation, retardation, and preference tests were used to assess the effects of extinguishing a conditioned saccharin aversion for three or nine trials. In Experiment 1, a summation test showed that saccharin aversion extinguished over nine trials reduced the aversion to a merely conditioned flavor (vinegar), whereas three saccharin extinction trials did not subsequently influence the vinegar aversion. Experiment 2 clarified that result, with unpaired controls equated on flavor exposure prior to testing; the results with those controls suggested that the flavor extinguished for nine trials produced generalization decrement during testing. In Experiment 3, the saccharin aversion reconditioned slowly after nine extinction trials, but not after three. Those results suggested the development of latent inhibition after more than three extinction trials. Preference tests comparing saccharin consumption with a concurrently available fluid (water in Experiment 4, saline in Experiment 5) showed that the preference for saccharin was greater after nine extinction trials than after three. However, saccharin preference after nine extinction trials was not greater, as compared with that for either latent inhibition controls (Experiments 4 and 5) or a control given equated exposures to saccharin and trained to drink saline at a high rate prior to testing (Experiment 5). Concerns about whether conditioned inhibition has been demonstrated in any flavor aversion procedure are discussed. Our findings help explain both successes and failures in demonstrating postextinction conditioned response recovery effects reported in the conditioned taste aversion literature, and they can be explained using a memory interference account. 相似文献
190.