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51.
This paper describes the basis for a new method of type synthesis of spatial mechanisms with the use of single-loop structural groups having zero degrees of freedom. Applying the binary system, the value 0 is used for R (revolute) and 1 is used for P (prismatic) pairs. The five-link spatial groups are described by codes both in the binary and decimal systems. All other groups are reduced to the basis of five-link spatial groups. In these cases two-degree-of-freedom and three-degree-of-freedom kinematic pairs are transformed to one-degree-of-freedom pairs, and these transformations are also described by codes in the binary and decimal systems. This method of coding can be programmed for digital computation and applied towards the automatic type synthesis in the design of spatial mechanisms. The system is equally clear for alphanumeric or for graphical display. To the designer it defines the diagram of the mechanism, pointing out the frame, the mobile links, the types of the kinematic pairs and their mutual disposition in the mechanism configuration.  相似文献   
52.
This paper introduces a generic decision-making framework for assigning resources of a manufacturing system to production tasks. Resources are broadly defined production units, such as machines, human operators, or material handling vehicles; and tasks are activities performed by resources. In the specific context of FMS, resources correspond to individual machines; tasks correspond to operations to be performed on parts. The framework assumes a hierarchical structure of the system and calls for the execution of four consecutive steps to make a decision for the assignment of a resource to a task. These steps are 1) establishment of decision-making criteria, 2) formation of alternative assignments, 3) estimation of the consequences of the assignments, and 4) selection of the best alternative assignment. This framework has been applied to an existing FMS as an operational policy that decides what task will be executed on which resource of this FMS. Simulation runs provide some initial results of the application of this policy. It is shown that the policy provides flexibility in terms of system performance and computational effort.  相似文献   
53.
This paper presents a mesh generation method of the advancing-front type which is designed in such a way that the well-known difficulties of the classical advancing-front method are not present. The retained solution consists of using the first steps of a Voronoï–Delaunay method to construct a background mesh which is then used to govern the algorithm. The two-dimensional case is considered in detail and possible extensions to adaption problems and three dimensions are indicated.  相似文献   
54.
An economic model is developed, to assist in the selection of minimum cost acceptance sampling plans by variables. The quadratic Taguchi loss function is adopted to model the cost of accepting items, with quality characteristics deviating from the target value. The case of a normally distributed quality characteristic with known variance is examined, and a simple and efficient optimization algorithm is proposed. Comparisons with other methods of deriving sampling plans reveal that the cost penalties for using an inappropriate plan may be very large.  相似文献   
55.
Rates of poor psychological adjustment of children with sickle cell disease remained relatively constant over initial and follow-up assessment points. 50 children (aged 7–12 yrs) and their mothers completed the initial protocol. 30 children completed the follow-up plus 5 additional children and their mothers. These Ss were aged 7–24 yrs at follow-up. With initial levels of adjustment controlled, children's strategies for coping with pain accounted for a significant increment in child-reported symptoms and mother-reported internalizing behavior problems at follow-up beyond the contribution of illness and demographic parameters and follow-up interval. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
56.
Discusses the generalization effects of 7 commercially available student social-skills training (SST) curricula. A table listing strategy, curricula, S characteristics, and results is given. Maintenance of improved behavior was seen as least successful when the "train and hope" strategy was used. The combination of SST and alteration of consequences in the classroom led to the most significant maintenance of results. The most effective programs were those that combined a variety of techniques. Improvement of behavior was obtained more often with withdrawn students than with aggressive students. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
57.
Reviews the book, The chemically dependent: Phases of treatment and recovery edited by Barbara C. Wallace (see record 1992-98403-000). While this book is ambitious, interesting, educational, and useful, it is also disappointing, repetitious, and incomplete. Because it tries to accomplish so much, it may appear to have succeeded too little. This book is organized around, and explicative of, several basic ideas which might have been controversial if not heretical had this book been published ten years ago. Section I, purporting to link specific "phases of recovery" to particular forms and functions of treatment, will certainly be useful for novice clinicians but falls short of its overstated goals and is thereby disappointing. Section II is a collection of moderately redundant chapters describing the etiology and treatment of substance abusers from the viewpoints of psychoanalytic, psychodynamic, ego psychology, and object-relations theorists and therapists. Section III focuses on cognitive-behavioral, self-help, and relapse-prevention treatments. Section IV is quite uneven in quality of writing and applicability of content, and could have benefited from closer editorial scrutiny or selectivity. The final section focuses on special needs of particular subpopulations of substance abusers: African-Americans, prison inmates, HIV/AIDS patients, persons who are homeless, those who have been sexually and physically abused, and others. According to the reviewer this is not the best book on substance abuse treatment, but it does present some clinically useful ideas and it is worth reading. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
58.
This study evaluated the effectiveness of four posttreatment programs designed to enhance the long-term maintenance of weight loss. Mildly and moderately obese adults (N?=?123) were randomly assigned to one of the following five conditions: (a) behavior therapy only; (b) behavior therapy plus a posttreatment therapist-contact maintenance program; (c) behavior therapy plus posttreatment therapist contact plus a social influence maintenance program; (d) behavior therapy plus posttreatment therapist contact plus an aerobic exercise maintenance program; or (e) behavior therapy plus posttreatment therapist contact plus both the aerobic exercise and social influence maintenance programs. All posttreatment programs were conducted in 26 biweekly sessions during the year following behavioral treatment for obesity. At an 18-month follow-up evaluation, all four conditions that combined behavior therapy with a posttreatment maintenance program yielded significantly greater long-term weight losses than behavior therapy alone. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
59.
A single-feed dual frequency compact microstrip antenna with a shorting pin is described. This new antenna configuration gives a large variation in frequency ratio of the two operating frequencies, without increasing the overall size of the antenna  相似文献   
60.
166 peace officers completed the MMPI and the MMPI-2 in one sitting. Results showed an overall concordance of 78% for the 2 tests when normal, high-point, and 2-point code types were grouped together and compared. A subset of well-defined profiles produced a concordance rate of 90%. Comparison of profile characteristics showed that half of the Ss produced the same high-point code type, one-third produced the same 2-point code type, 70% produced normal profiles on both tests, and all MMPI and MMPI-2 scales were highly correlated. These figures are highly similar to those found previously for 2 administrations of the MMPI. When the MMPI was compared to the MMPI-2 scored on original norms, 2 scales were found to differ significantly: Men and women both scored lower on Scale D (Depression) of the revised test; on Scale Mf (Masculinity-Femininity) of the MMPI-2, women scored higher and men scored lower. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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