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31.
Action calculi, which generalise process calculi such as Petri nets, π-calculusand ambient calculus, have been presented
in terms of action graphs. We here offer linear action graphs as a primitive basis for action calculi. This paper presents the category of embeddings of undirected linear
action graphs without nesting, using a novel form of graphical reasoning which simplifies some otherwise complex manipulations
in regular algebra. The results are adapted in a few lines to directed graphs. This work is part of a long-term search for
a uniform behavioural theory for process calculi.
Received October 2000 / Accepted in revised form April 2001 相似文献
32.
33.
Airframe riveting is a critical process that requires high levels of process monitoring and quality assurance due to the very
high risk associated with the failure of such joints. This paper describes the development of the enabling technology developed
for a machine vision-based process monitoring system. One of the key factors affecting the performance of a machine vision
system is the quality of the lighting. In the application described in this paper the available lighting was severely limited
by the confined space in which the system had to operate. The problem was also compounded by the reflective nature of the
objects to be examined. The initial images obtained were not suitable for further processing due to the presence of significant
shadows and specular reflections. A novel solution to this problem based on multiple wavelength illumination and signal processing
is presented along with results from experimental trials of the approach. 相似文献
34.
SIMULATION STUDIES OF THE REMOVAL OF WATER FROM ETHANOL BY A CATALYTIC DISTILLATION PROCESS 总被引:1,自引:0,他引:1
Christina B. Dirk-Faitakis Karl T. Chuang 《Chemical Engineering Communications》2005,192(11):1541-1557
A new approach based on catalytic distillation (CD) technology was proposed to remove water from ethanol. Isobutylene was introduced to react with water in the CD column. The commercial software simulation tool Aspen Plus was used to investigate the effects of key design factors such as operating pressure and temperature, reactant ratios, reflux and distillate to feed ratios, number of separation and reaction stages, and feed and reaction zone location. It was found that the CD technology offers potential advantages of reduced energy consumption and reduced capital cost over traditional approaches for the removal of water from ethanol. 相似文献
35.
36.
等径弯角挤压工艺(ECAEP)研究现状 总被引:3,自引:0,他引:3
等径弯角挤压是制备块状细晶材料的一种大塑性变形工艺,目前得到国内外高度重视.本文简要介绍了等径弯角挤压工艺的基本原理和变形特点,从理论上对其变形方式和机理进行了分析,并详细介绍了该工艺的应用领域。 相似文献
37.
黄药合成工艺的生产实践 总被引:1,自引:0,他引:1
本文介绍了永平铜矿强力公司黄药合成的工艺概况 ,并论述了在生产实践中对提高产品质量所采取的主要措施 相似文献
38.
Mining process models with non-free-choice constructs 总被引:6,自引:0,他引:6
Lijie Wen Wil M. P. van der Aalst Jianmin Wang Jiaguang Sun 《Data mining and knowledge discovery》2007,15(2):145-180
Process mining aims at extracting information from event logs to capture the business process as it is being executed. Process
mining is particularly useful in situations where events are recorded but there is no system enforcing people to work in a
particular way. Consider for example a hospital where the diagnosis and treatment activities are recorded in the hospital
information system, but where health-care professionals determine the “careflow.” Many process mining approaches have been
proposed in recent years. However, in spite of many researchers’ persistent efforts, there are still several challenging problems
to be solved. In this paper, we focus on mining non-free-choice constructs, i.e., situations where there is a mixture of choice
and synchronization. Although most real-life processes exhibit non-free-choice behavior, existing algorithms are unable to
adequately deal with such constructs. Using a Petri-net-based representation, we will show that there are two kinds of causal
dependencies between tasks, i.e., explicit and implicit ones. We propose an algorithm that is able to deal with both kinds
of dependencies. The algorithm has been implemented in the ProM framework and experimental results shows that the algorithm
indeed significantly improves existing process mining techniques. 相似文献
39.
40.
工艺系统刚度产生的误差原理与分析 总被引:2,自引:0,他引:2
李海明 《电子工业专用设备》2002,31(1):41-44
根据对工艺系统受力变形的分析 ,阐述了工艺系统刚度对零件加工精度的影响 ,并简要提出了提高工艺系统刚度的办法 相似文献