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231.
Reservoir management is inherently multicriterial, since any release decision involves implicit trade-offs between various conflicting objectives. The release decision reflects concerns such as flood protection, generation of hydroelectric power, dilution of wastewater and heated effluent, supply of municipal, agricultural and industrial water, maintenance of environmental standards and satisfaction of recreational needs. This paper presents a framework for analysing trade-offs between several decision criteria and includes the dilution of heated effluents from downstream thermoelectric power generation in an optimization model for reservoir management. The model is formulated and analysed in an interactive multicriteria decision-making (MCDM) modelling framework. Rather than providing specific target levels or ad hoc constants in a goal-programming framework as proposed elsewhere, this multicriteria framework suggests a systematic way of evaluating trade-offs by progressive preference assessment. The MCDM model, based on a Chebyshev metric and a contracted cone approach, is learning-oriented and permits a natural exploration of the decision space while maintaining non-dominated decisions. A detailed case study of the Shellmouth Reservoir in Manitoba, Canada serves as an illustration of the model. © 1998 John Wiley & Sons, Ltd.  相似文献   
232.
Family systems therapy originated in the 1960s, 1970s, and 1980s through the work of innovative thinkers and clinicians. However, despite the creative contributions of the mentioned colleagues and of later innovations in family therapy theory and practice, it seems as though the dominant culture of establishment psychiatry in the United States (and in most Western countries) to this day has not seriously incorporated relationships, social context, or community connectedness into the treatment of individuals with psychiatric diagnoses. For the “psychiatric” patients diagnosed according to the DSM-5, the dominant underlying epistemological perspective is the medical “scientific” paradigm. Within this approach there is a dearth of reflections about the truthfulness of so-called “empirical facts” and a lack of skepticism about the techniques of “measurement” of the psychiatric illness. The alternative, relationship-oriented, context-sensitive, and community-connected thinking paradigm is highlighted here in contrast to the “psychiatric” foundation. This paradigm consists of (a) the awareness that all human Subjects (including “psychiatric” clients) are constituted as such by their relational connection to others; (b) the awareness of our sensitivity to and embeddedness in a socio-economic, cultural, and racial context; and (c) the awareness of our involvement in and connectedness with many kinds of communities.  相似文献   
233.
A dynamic systems analysis was conducted to distinguish the parent–child interactions of pure externalizing children from children comorbid for externalizing and internalizing problems. Thirty-three parents and clinically referred children (8–12 years old) discussed a problem for 4 min and then tried to wrap up in response to a signal (a perturbation). The perturbation was intended to increase the pressure on the dyad, triggering a reorganization of their behavioral system. We hypothesized that the comorbid group would be distinguished from the externalizing-only group as a result of this reorganization, but not before. The sequential data were analyzed using a combination of case-sensitive (state space grids and chi-square analyses) and group-based, multivariate techniques (log-linear modeling). Results revealed that externalizing dyads engaged in a permissive pattern throughout the problem-solving session, whereas comorbid dyads shifted from a permissive pattern to a mutually hostile pattern after the perturbation. These findings punctuate the need for a dynamic systems approach to the study of relationship processes associated with the development of childhood psychopathology. Theoretical and clinical implications are discussed.  相似文献   
234.
A symbolic computer model, employing the perceptual strategy, is presented for solving Tower of Hanoi problems. The model is calibrated—in terms of the number of problems solved, time taken, and number of moves made—to the performance of 20 normal subjects. It is then "lesioned" by increasing the decay rate of elements in working memory to model the performance of 20 patients with lesions to the prefrontal cortex. The model captures both the main effects of subject groups (patients and normal controls) performance, and the subject groups (patients and normal controls) by problem difficulty interactions. This leads us to support the working memory hypothesis of frontal lobe functions, but for a narrow range of problems.  相似文献   
235.
This paper describes an integrative approach to marital and family therapy in which psychodynamic (particularly object relations), family systems, and behavioral (particularly cognitive–behavioral) theory are blended in a flexible and tailored therapeutic approach. Human personality in its most significant contexts is a consistent focus. Background factors in the development to the approach and illustrative case materials are included.  相似文献   
236.
On programming KARO agents   总被引:1,自引:0,他引:1  
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239.
There has been an escalation in the number of children identified with autism spectrum disorders in recent years. To increase the likelihood that treatments for these children are effective, interventions should be derived from sound theory and research evidence. Absent this supportive foundation, intervention programs could be inconsequential if not harmful. Although atypical, the development of children with autism should be considered initially from the perspective of the same variables that affect the development of typical children. In addition, the developmental deviations that characterize autism must be considered when developing intervention programs. Behavioral systems models describe both typical and atypical development and emphasize dynamic multidirectional person-environment transactions. The environment is viewed as having multiple levels, from the individuals with autism themselves, to larger societal and cultural levels. Behavioral systems models of human development can be generalized to a transactional systems model of services for children with autism. This model is the foundational theoretical position of the Southern Illinois University Center for Autism Spectrum Disorders. The center's programs are described to illustrate the application of the model to multiple levels of the social ecology.  相似文献   
240.
Complex motion during standing is typical in daily living and requires movement of both the thoracic and lumbar spine; however, the effects of lumbar spine posture on thoracic spine motion patterns remain unclear. Thirteen males moved to six positions involving different lumbar (neutral and flexed) and thoracic (flexed and twisted) posture combinations. The thoracic spine was partitioned into three segments and the range of motion from each posture was calculated. Electromyographical data were collected from eight muscles bilaterally. Results showed that with a flexed lumbar spine, the lower-thoracic region had 14.83° and 15.61° more flexion than the upper- and mid-thoracic regions, respectively. A flexed lumbar spine significantly reduced the mid-thoracic axial twist angle by 5.21° compared to maximum twist in the mid-thoracic region. Functional differences emerged across muscles, as low back musculature was greatest in maintaining flexed lumbar postures, while thoracic erector spinae and abdominals showed bilateral differences with greater activations to the ipsilateral side. Combined postures have been previously identified as potential injury modulators and bilateral muscle patterns can have an effect on loading pathways. Overall, changes in thoracic motion were modified by lumbar spine posture, highlighting the importance of considering a multi-segmented approach when analyzing trunk motion.  相似文献   
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