Within the computerscience curriculum, the social and ethical aspects of computing can be partially addressed with a specialized course on these issues. This paper discusses one such course, briefly examining its str...
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This paper presents an assistant database design system, ExpertDB, which is based on entity-relationship (ER) approach. The approach is to synthesize a normalized ER schema (which consists of entity set and relationsh...
ISBN:
(纸本)9780897913720
This paper presents an assistant database design system, ExpertDB, which is based on entity-relationship (ER) approach. The approach is to synthesize a normalized ER schema (which consists of entity set and relationship set expressions) from functional dependencies (FD). Using as input the set of attributes and FD's, we derive the minimal cover of FD's, partition and regroup FD's, and finally form the entities and relationship sets. In every aspect of these derivations, ExpertDB provides assistance to the user, which is usually the database administrator (DBA), in the database design. The resulting ER schema is then mapped to relational schema.
Herein, it is shown that by exploiting integral definitions of well known special functions, through generalizations and differentiations, broad classes of definite integrals can be solved in closed form or in terms o...
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It is shown that Symbolic Computation provides excellent tools for solving quantum mechanical problems by perturbation theory. The method presented herein solves for both the eigenfunctions and eigenenergies as power ...
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It is shown that Symbolic Computation provides excellent tools for solving quantum mechanical problems by perturbation theory. The method presented herein solves for both the eigenfunctions and eigenenergies as power series in the order parameter where each coefficient of the perturbation series is obtained in closed form. The algorithms are expressed in the Maple symbolic computation system but can be implemented on other systems. This approach avoids the use of an infinite basis set and some of the complications of degenerate perturbation theory. It is general and can, in principle, be applied to many separable systems.
We present a real-time robot motion planner that is fast and complete to a resolution. The technique is guaranteed to find a path if one exists at the resolution, and all paths returned are safe. The planner can handl...
ISBN:
(纸本)9780897913447
We present a real-time robot motion planner that is fast and complete to a resolution. The technique is guaranteed to find a path if one exists at the resolution, and all paths returned are safe. The planner can handle any polyhedral geometry of robot and obstacles, including disjoint and highly concave unions of *** planner uses standard graphics hardware to rasterize configuration space obstacles into a series of bitmap slices, and then uses dynamic programming to create a navigation function (a discrete vector-valued function) and to calculate paths in this rasterized space. The motion paths which the planner produces are minimal with respect to an L1 (Manhattan) distance metric that includes rotation as well as *** examples are shown illustrating the competence of the planner at generating planar rotational and translational plans for complex two and three dimensional robots. Dynamic motion sequences, including complicated and non-obvious backtracking solutions, can be executed in real time.
We consider the problem of evaluating a boolean function P(x 1 ,…,x n ), by asking queries of the form “x i =?”, and receiving answers which may not always be truthful. Assuming that the total number of lies does n...
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We consider the problem of evaluating a boolean function P(x 1 ,…,x n ), by asking queries of the form “x i =?”, and receiving answers which may not always be truthful. Assuming that the total number of lies does not exceed E, we present an algorithm with cost O(n+s P E+t P E), where s P is the maximal size of a minterm of P(x) and t P ‘is the maximal size of a maxterm. We also prove that if P is monotone, then any algorithm for evaluating P must ask Ω(s P E+t P E) queries for some input.
The existence of modularity in the organization of nervous systems (e.g. cortical columns and olfactory glomeruli) is well known. We show that localized activity patterns in a layer of cells, collective excitations, c...
The existence of modularity in the organization of nervous systems (e.g. cortical columns and olfactory glomeruli) is well known. We show that localized activity patterns in a layer of cells, collective excitations, can induce the formation of modular structures in the anatomical connections via a Hebbian learning mechanism. The networks are spatially homogeneous before learning, but the spontaneous emergence of localized collective excitations and subsequently modularity in the connection patterns breaks translational symmetry. This spontaneous symmetry breaking phenomenon is similar to those which drive pattern formation in reaction-diffusion systems. We have identified requirements on the patterns of lateral connections and on the gains of internal units which are essential for the development of modularity. These essential requirements will most likely remain operative when more complicated (and biologically realistic) models are considered.
When we think of energy issues, we generally conjure up ideas of conflicts between producers and consumers. These translate into visions of grand ideological conflicts between the left and the right. Wildavsky and Ten...
When we think of energy issues, we generally conjure up ideas of conflicts between producers and consumers. These translate into visions of grand ideological conflicts between the left and the right. Wildavsky and Tennenbaum (1981) speak of battles between "preservationists" and "industrialists." Kalt (1981) argues that "[tihe domestic energy 'crisis' is, far more than anything else, a quarrel over income distribution." Ideological straight fights are marked by a single dimension of conflict. In particular, ideological politics, as opposed to religious or ethnic cleavages, suggests a battle between left and right--or, producers and consumers in the case of energy battles. When there are only two contestants, one is sure to win if the group decision is made by majority rule. Even in the United States Congress, where complex rules often frustrate coherent policy formation, strongly-held positions can prevail over obstructionists if they are determined enough. Yet, during the 1970s many attempts to form a "national energy policy" failed. In the 1980s Congress again stumbled in making natural gas policy as it defeated both decontrol and recontrol proposals.
We address the problem of assigning multiple copies of n independently developed versions of a program to a set of m(m > n) possibly heterogeneous processors to maximize system reliability. This problem is viewed a...
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CARLSON, CMFIREMAN, HCraig M. Carlson:is a general engineer in the Computer Aided Engineering Division (SEA-507). He received his B.S. degree in naval architecture from the University of Michigan in 1970. In 1972
he was selected for the NAVSEC Hull Division's Long Term Training Program at the University of Michigan and received his M. S. E. degree in naval architecture in 1973. Additionally he has done graduate work in computer science at The Johns Hopkins University. Mr. Carlson began his career with the Naval Ship Engineering Center in 1970 where he worked in the Ship Arrangements Branch. While in ship arrangements he was task leader for the PGG PCG PHM and MCM ship designs. In addition he was project engineer for shipboard stowage ship space classification system and ship standard nomenclature. He was technical manager of the CASDAC arrangement subsystem and the CASDAC hull design system. In 1982 he joined what is now the Computer Aided Engineering Division. Currently he is the manager for the computer supported design version XX system. Besides ASNE which he joined in 1972 he is a member of SNA ME and the U.S. Naval Institute. Howard Fireman:is a naval architect in the Ship Arrangements Design Division (SEA-55W1). He received his B. S. E. degree in naval architecture from the University of Michigan in 1979. In 1983
he was selected for NavSea's Long Term Training Program at the University of Michigan and received his M. S. E. degree in naval architecture with a specialization in ship production and computer aided ship design in 1985. Mr. Fireman began his career with the Naval Ship Engineering Center in 1977 as an engineering cooperative student. Since graduating from the NavSea EIT program he has worked in the Ship Arrangements Design Division. He was task leader for the AOE-6 AE-36 T-AH ARS-SO and SWATH T-AGOS ship designs. He is technical manager of the CSD General Arrangement Design System and is currently the Hull Group CSD coordinator. Besides ASNE which he joined in 1979 he is a member of SNA ME ASE a
The ever increasing complexity of ships coupled with cost, schedule, and resource constraints require innovative methods by the Naval Sea Systems Command's ship design community to meet this challenge. This paper ...
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The ever increasing complexity of ships coupled with cost, schedule, and resource constraints require innovative methods by the Naval Sea Systems Command's ship design community to meet this challenge. This paper describes the effort by the NavSea Ship Arrangement Design Division to dramatically improve its ship design capability by the use of a system of computer-based design tools called the General Arrangement Design System. The General Arrangement Design System (GADS) is based on the engineering requirements of the ship arrangement design process. GADS is currently being used as a production engineering tool. This paper is organized into two parts. Part I describes the General Arrangement Design System, and Part II describes the general arrangement design methodology.
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