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101.
In 1953, Karnaugh maps were developed at the Harvard Computation Laboratory for the minimization of Boolean algebraic expressions (as an approach to logic circuit synthesis) [5]. 相似文献
102.
Business Process Execution Language for Web Services (BPEL4WS) allows defining both, business processes that make use of Web services, and business processes that externalize their functionality as Web services. This short paper introduces the basic language elements of BPEL4WS using a simple example. The concepts underlying the language are briefly explained: establishing bilateral partnerships, correlating messages and processes, defining the order of the activities of a business process, event handling, handling exceptions via long-running transactions, and the usage of BPEL4WS in pure B2B scenarios. The paper finishes off by presenting the resulting application structure and the resulting economical implications. 相似文献
103.
104.
Approximating minimum cocolorings 总被引:1,自引:0,他引:1
A cocoloring of a graph G is a partition of the vertex set of G such that each set of the partition is either a clique or an independent set in G. Some special cases of the minimum cocoloring problem are of particular interest.We provide polynomial-time algorithms to approximate a minimum cocoloring on graphs, partially ordered sets and sequences. In particular, we obtain an efficient algorithm to approximate within a factor of 1.71 a minimum partition of a partially ordered set into chains and antichains, and a minimum partition of a sequence into increasing and decreasing subsequences. 相似文献
105.
Coloring terms (rippling) is a technique developed for inductive theorem proving that uses syntactic differences of terms to guide the proof search. Annotations (colors) to symbol occurrences in terms are used to maintain this information. This technique has several advantages; for example, it is highly goal oriented and involves little search. In this paper we give a general formalization of coloring terms in a higher-order setting. We introduce a simply typed calculus with color annotations and present appropriate algorithms for the general, pre-, and pattern unification problems. Our work is a formal basis to the implementation of rippling in a higher-order setting, which is required, for example, in the case of middle-out reasoning. Another application is in the construction of natural the language semantics, where the color annotations rule out linguistically invalid readings that are possible using standard higher-order unification. 相似文献
106.
Analytische Möglichkeiten einer neuen Gerätegeneration. Weiterentwicklung des Verfahrens mit synthetischer Eichung bis zur Bestimmungsgrenze 2 μg/g. 相似文献
107.
108.
Pipe fabrication for the repair sector. The paper discusses the changes in pipe fabrication that have taken place in recent years. These enable repair work to be carried out more efficiently, without thereby impairing the flexibility and speed of operation that are essential to maintenance work. A prerequisite for this is that work on the pipes be transferred to workshops. Only here is it possible for manual operations, such as manual welding, to be reduced to a minimum and be replaced by mechanized or semi-mechanized welding methods. The use of modern machines for bending the pipes is more economic than the welding in of pipe bends. Necking out of the pipes by mechanical means or the use of mechanically pre-fabricated connections permit optimum preparation of the weld seam for branch fittings. Any additional work on the pipes, where this is necessary, is carried out at workplaces specially designed for the purpose. 相似文献
109.
Albert Kochendoerfer Kunihiko Kobayashi Horst Dieter Schulze Karl Edgar Hagedorn Ulrich Ruediger 《Engineering Fracture Mechanics》1976,8(4):737-741
The flow and fracture stresses, σyg and σfg (δ = crack tip displacement), of sharply notched bending specimens of a structural steel U St 37-1 are measured in the temperature range from full scale to small scale yielding. The best adaption of the experimental results for σfg is obtained by a curve which exhibits an intermediate transition, i.e. which follows in a temperature range between an upper, TtM1 and a lower, Ttl1, transition temperature to the curve σyg(T) for the flow stress with a constant δ = δ1. This transition corresponds to that of the slip to the twin nucleated fracture. Two analyses [3,5] according to the local fracture stress, σf*, concept show that the amount and the temperature dependence of σf* are somewhat different for both methods, but that both exhibit an increase of σf* in the transition range. It is concluded that each transition in the nucleation mode of the fracture is connected with such a transition in the fracture stress. It may, however, become indistinct or even be covered by the scatter of the experimental points. 相似文献
110.