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131.
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Explored, in 2 experiments, the effects of lateral vs medial laminar lesions of the hyperstriatum in pigeons; medial lesions were largely confined to the hyperstriatum accessorium, and lateral lesions to the hyperstriatum dorsale and hyperstriatum ventrale. In Exp 1, lateral, but not medial, lesions disrupted acquisition of a simultaneous conditional discrimination; both medial and lateral lesions disrupted reversal of the discrimination. The reversal deficits of the medial and lateral groups were quantitatively similar, and both groups showed exaggerated positional responding. In Exp 2, neither medial nor lateral lesions disrupted acquisition of a successive conditional discrimination. Lateral hyperstriatal damage does not obtain a general disruption of conditional learning; it is speculated that the lateral hyperstriatum may play a critical role in configural learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
133.
Mark Grigorian 《The Structural Design of Tall and Special Buildings》1993,2(3):233-252
This paper introduces a simple approach for the study of the structural phenomena associated with the lateral response of regular highrise frames. The concept is based upon the assumption that the structure is composed of imaginary modules that fit within the actual bays of the framework, and that all imaginary modules deform through similar shapes by formation of points of inflexion at similar locations. The imaginary modules of a story are combined to form an equivalent ‘basic module’ that possesses the same structural characteristics as the corresponding story level subframe. The concept is used to establish an analogy between the lateral response of highrise structures and discretized Timoshenko beam-columns with similar boundary conditions. The properties of the basic module have been employed in conjunction with the techniques of finite difference calculus to derive the governing equation of motion of a regular discretized Timoshenko beam under uniform compression. The use of the concept is further utilized to obtain a number of closed form formulae for the initial design of multistory structures. These include expressions for the determination of the natural frequencies, the P-delta effects, as well as the critical buckling loads of regular multistory frames. Numerical examples have been provided to demonstrate the applications and the simplicity of the proposed solutions. 相似文献
134.
Mark D. Pardue 《工程教育杂志》1993,82(1):48-50
Computer-Integrated Manufacturing (CIM) has over the past decade become a key component in revitalizing U.S. manufacturing industry. To support much of this CIM activity, colleges and universities have started CIM-related courses and programs. A major problem that these schools have had is in determining the structure of their “CIM” program. This paper will discuss the major factors to be considered in developing the overall architecture for a CIM Program in a 4-year institution, detailing goals and objectives, participants and leadership roles, and the major components for a successful CIM Program. Curriculum issues are not discussed, as any specific curriculum will vary depending upon the degree program. 相似文献
135.
Qidong Cao Mark A. Mcknew 《International Journal of Flexible Manufacturing Systems》1994,6(2):155-172
A new optimization model is discussed for the design of cellular manufacturing systems. It is based on an integer programming formulation that updates some other models by eliminating redundant machine assignment and cost coefficients dependent on cell configuration. To reduce computational burdens, a simplified integer programming model and a decomposition algorithm are proposed. Several computer solutions were performed to evaluate the performance of the new model. The computational results are discussed. 相似文献
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Britain's new offshore oil industry might have generated much additional employment especially in the building, manning and supply of rigs. But there was a failure at first to take proper advantage; little was done to train people in new skills. Consequently the oil companies brought in equipment and skilled personnel from abroad. Eventually efforts were made to improve matters and the paper examines the steps taken to bring more of the employment benefits to Britain, but finds only partial success. 相似文献
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