集成化企业建模方法与工具系统研究

研究了企业建模方法的发展趋势 ,提出了一个集成化的企业建模方法 ,给出了建模框架体系和建模方法 ,并设计了一个基于CORBA软件总线的集成化企业建模与仿真优化系统。所提出的建模方法与设计的软件工具 ,对于促进集成化企业建模方法学的研究 ,开发具有我国自主版权的建模与优化工具系统 ,具有实际应用价值。

制造企业系统的一个集成化参考模型

指出当前用面向对象建模方法对制造企业进行建模活动中存在的问题 ,提出一种新的面向对象建模方法 ,该方法基本能克服现存问题 ,并用该方法为制造企业系统建立了一个参考模型。该模型覆盖了在工厂管理中的经营操作与制订决策的过程

自动生产线和柔性制造系统的建模、分析与控制

自动生产线和柔性制造系统是典型的离散事件动态系统,近几年在控制理论界受到极大重视。本文首先对自动生产线的建模与分析的研究概况做了综述,重点放在排队网络模型。然后介绍了柔性制造系统的管理与控制问题。

基于数字化生产模型的在线故障诊断技术研究

提出了一种基于数字化的生产模型,使用控制图、故障树分析和专家知识,能够进行制造过程实时监控的诊断,该模型提高了故障诊断系统的可靠性,并提供了可实际操作的可视化建模工具。所开发的在线统计过程控制系统能够根据生产事件的监测,动态响应制造过程变化。该系统运用可视化建模工具,根据专家经验进行故障树建模,通过故障树自动生成专家系统诊断规则库,实现诊断知识的自动获取。将该系统应用于汽车变速箱装配过程的检测与故障诊断,验证了方法的有效性。

基于数字化生产模型的事件建模系统设计

文章主要对基于数字化生产模型的事件建模系统进行了介绍。首先引入了支撑事件建模系统的MES基础运行平台,介绍了平台的功能以及系统结构;接着描述了事件的相关概念,并对事件建模系统的设计方法进行了介绍,最后给出了系统的具体应用实例。

水-岩土反应的力学与环境效应研究

The research on mechanical effects of water-rock and soil interaction on deformation and failure of rocks and soils involves three aspects of mechanics, physics and chemistry. It is the cross between geochemistry and rock mechanics and soil mechanics. To sum up, the mechanical effects of water-rock and soil interaction is related to many complex processes. Research in this respect has been being an important forward field and has broad prospects. In connection with the mechanism of the effects of the chemical action of water-rock on deformation and failure of rocks and soils, the research significance, the present state, the developments in this research domain are summarized. Author prospects the future of this research. The research of the subject should be possessed of important position in studying engineering geology and will lead directly to a new understand on geological hazard and control research. In order to investigation the macroscopic mechanics effects of chemical kinetics of water-rock interaction on the deformation and failure, calcic rock, red sandstone and grey granite reacting chemically with different aqueous solution at atmospheric temperature and atmospheric pressure are uniaxially compressed. The quantitative results concerning the changes of uniaxially compressive strength and elastic modulus under different conditions are obtained. It is found that the mechanical effects of water on rock is closely related to the chemical action of water-rock or the chemical damage in rock, and the intensity of chemical damage is direct ratio to the intensity of chemical action in water-rock system. It is also found that the hydrochemical action on rock is time-dependent through the test. The mechanism of permeation and hydrochemical action resulting in failure of loaded rock mass or propagation of fractures in rocks would be a key question in rock fracture mechanics. In this paper, the fracture mechanical effects of chemical action of water-rock and their time- and chemical environment-dependent behavior in grey granite, green granite, grey sandstone and red sandstone are analyzed by testing K_(IC) and COD of rock under different conditions. It is found that: ①the fracture mechanical effect of chemical action of water-rock is outstanding and time-dependent, and high differences exist in the influence of different aqueous solution, different rocks, different immersion ways and different velocity of cycle flow on the fracture mechanical effects in rock. ②the mechanical effects of water-rock interaction on propagation of fractures is consistent with the mechanical effects on the peak strength of rock. ③the intensity of the mechanical fracture effects increases as the intensity of chemical action of water-rock increases. ④iron and calcium ion bearing mineral or cement in rock are some key ion or chemical composition, and especially iron ion-bearing mineral resulting in chemical action of water-rock to be provided with both positive and negative mechanical effects on rock. Through the above two tests, we suggest that primary factors influencing chemical damage in rock consist of the chemical property of rock and aqueous solution, the structure or homogeneity of rocks, the flow velocity of aqueous solution passing through rock, and cause of formation or evolution of rock. The paper explores the mechanism on the mechanical effects of water-rock interaction on rock by using the theory of chemistry and rock fracture mechanics with chemical damage proposed by author, the modeling method and the energy point of view. In this paper, the concept of absorbed suction between soil grains caused by capillary response is given and expounded, and the relation and basic distinction among this absorbed suction, surface tension and capillary pressure of the soil are analyzed and established. The law of absorbed suction change and the primary factors affecting it are approached. We hold that the structure suction are changeable along with the change of the saturation state in unsaturated soils. In view of this, the concept of intrinsic structure suction and variable structure suction are given and expounded, and this paper points out: What we should study is variable structure suction when studying the effective stress. By IIIy κHH's theory of structure strength of soils, the computer method for variable structure suction is analyzed, the measure method for variable structure suction is discussed, and it reach the conclusions: ①Besides saturation state, variable structure suction is affected by grain composition and packing patter of grains. ②The internal relations are present between structure parameter N in computing structure suction and structure parameter D in computing absorbed suction. We think that some problems exit in available principle of effective stress and shear strength theory for unsaturated soil. Based on the variable structure suction and absorbed suction, the classification of saturation in soil and a principle of narrow sense effective stress are proposed for unsaturated soils. Based on generalized suction, the generalized effective stress formula and a principle of generalized effective stress are proposed for unsaturated soils. The experience parameter χ in Bishop's effective stress formula is defined, and the principal factors influencing effective stress or χ. The primary factor affecting the effective stress in unsaturated soils, and the principle classifying unsaturated soils and its mechanics methods analyzing unsaturated soils are discussed, and this paper points out: The theory on studying unsaturated soil mechanics should adopt the micromechanics method, then raise it to macromechanics and to applying. Researching the mechanical effects of chemical action of water-soil on soil is of great importance to geoenvironmental hazard control. The texture of soil and the fabric of soil mass are set forth. The tests on physical and mechanical property are performed to investigate the mechanism of the positive and negative mechanical effects of different chemical property of aqueous solution. The test results make clear that the plastic limit, liquid limit and plasticity index are changed, and there exists both positive and negative effects on specimens in this test. Based on analyzing the mechanism of the mechanical effects of water-soil interaction on soil, author thinks that hydrochemical actions being provided with mechanical effects on soil comprise three kinds of dissolution, sedimentation or crystallization. The significance of these tests lie in which it is recognized for us that we may improve, adjust and control the quality of soils, and may achieve the goal geological hazard control and prevention.The present and the significance of the research on environmental effects of water-rock and soil interaction. Various living example on geoenvironmental hazard in this field are enumerated. Following above thinking, we have approached such ideals that: ①changing the intensity and distribution of source and sink in groundwater flow system can be used to control the water-rock and soil interaction. ②the chemical action of water-rock and soil can be used to ameliorate the physical and mechanical property of rocks and soils. Lastly, the research thinking and the research methods on mechanical effects and environmental effects of water-rock and soil interaction are put forward and detailed.

工作幸福感的结构、测量及作用机制

With the emergence and development of positive psychology, happiness has been the focus of academia and business. However, there is no uniform measure of happiness, because of many different theories of happiness, which are not compatible with others. It bounds the further development of happiness theory. It is also the same with the research of work well-being, which refers to the emotional experience and quality of psychological functioning of employee in the workplace. Subjective well-being (SWB) and psychological well-being (PWB) are two major theories of happiness. Prior research has demonstrated the integration of these two theories theoretically, but still needs more empirical support. Besides, in line with the development of positive psychology, a body of knowledge about positive leadership is advocated. Transformational leadership is treated as one kind of positive leadership, since it emphasizes the leader’s motivational and elevating effect on followers. But the extent to which the transformational leadership can enhance work well-being, and what the mechanism is, these are the questions need to be explored. Based on the integration of SWB and PWB, this research tried to investigate the structure, measurement and mechanism of work well-being, and combining with the theory of transformational leadership, this study also tried to investigate the relationship between transformational leadership and work well-being. The structure and measurement of work well-being, the relationships between work well-being and job characteristics (including job resources and job demands), the relationships among transformational leadership, job resources, work well-being and corresponding outcomes, the relationships among transformational leadership, job demands, work well-being and corresponding outcomes, and the relationships among transformational leadership, group job characteristics, group work well-being and corresponding group outcomes were explored by using content analysis, Subject Matter Experts (SMEs) discussion, and structural questionnaire surveys. More than 7000 subjects were surveyed, and Explore Factor Analysis (EFA), Confirm Factor Analysis (CFA), Structural Equation Modeling (SEM), Hierarchical Linear Modeling (HLM) and other statistics methods were used. The following is the major conclusions. Firstly, work well-being is a two high-order factors structure, which includes affective well-being (AWB) and cognitive well-being (CWB). AWB is similar to SWB, and CWB is similar to PWB. Besides, the construct of AWB includes sub-dimensions of positive emotional experience and negative emotional experience. And the construct of CWB consists of work autonomy, personal growth, work competent, and work significance. Secondly, the relationships between job characteristics and AWB and CWB are different. On one hand job demands are directly related to AWB, and are indirectly related to CWB through the full mediation of AWB, on the other job resources are directly related to CWB, and are indirectly related to AWB through the full mediation of CWB, which means AWB and CWB reciprocally influences each other in the model of job demands-resources. These results were concluded as the process model of work well-being. Thirdly, AWB and CWB are positively related to many workplace outcomes, including job satisfaction, group satisfaction, organizational commitment, turnover intention, job performance, organizational citizenship behavior (OCB), and general psychological health and general physiological health. Fourthly, transformational leadership is indirectly related to CWB through the full mediation of job resources, and is related to AWB through the partial mediation of job demands. Meanwhile, transformational leadership is related to many workplace outcomes through the mediation of job characteristics and work well-being. These results implied that transformational leadership is indeed one kind of positive leadership. Fifthly, in the group level, transformational leadership is indirectly related to group CWB through the full mediation of group job resources, and is related to group AWB through the full mediation of group job demands. Group AWB has positive influence on group CWB, but not vice versa. Group job characteristics and group work well-being fully mediate the relationships between transformational leadership and intragroup cooperation and group performance.

Automatic Design of a Maglev Controller in State Space

We describe the automatic synthesis of a global nonlinear controller for stabilizing a magnetic levitation system. The synthesized control system can stabilize the maglev vehicle with large initial displacements from an equilibrium, and possesses a much larger operating region than the classical linear feedback design for the same system. The controller is automatically synthesized by a suite of computational tools. This work demonstrates that the difficult control synthesis task can be automated, using programs that actively exploit knowledge of nonlinear dynamics and state space and combine powerful numerical and symbolic computations with spatial-reasoning techniques.

BUILD: A Tool for Maintaining Consistency in Modular Systems

Build is a tool for keeping modular systems in a consistent state by managing the construction tasks (e.g. compilation, linking, etc.) associated with such systems. It employs a user supplied system model and a procedural description of a task to be performed in order to perform the task. This differs from existing tools which do not explicitly separate knowledge about systems from knowledge about how systems are manipulated. BUILD provides a static framework for modeling systems and handling construction requests that makes use of programming environment specific definitions. By altering the set of definitions, BUILD can be extended to work with new programming environments to perform new tasks.

On Motion Planning with Uncertainty

Robots must successfully plan and execute tasks in the presence of uncertainty. Uncertainty arises from errors in modeling, sensing, and control. Planning in the presence of uncertainty constitutes one facet of the general motion planning problem in robotics. This problem is concerned with the automatic synthesis of motion strategies from high level task specification and geometric models of environments. In order to develop successful motion strategies, it is necessary to understand the effect of uncertainty on the geometry of object interactions. Object interactions, both static and dynamic, may be represented in geometrical terms. This thesis investigates geometrical tools for modeling and overcoming uncertainty. The thesis describes an algorithm for computing backprojections o desired task configurations. Task goals and motion states are specified in terms of a moving object's configuration space. Backprojections specify regions in configuration space from which particular motions are guaranteed to accomplish a desired task. The backprojection algorithm considers surfaces in configuration space that facilitate sliding towards the goal, while avoiding surfaces on which motions may prematurely halt. In executing a motion for a backprojection region, a plan executor must be able to recognize that a desired task has been accomplished. Since sensors are subject to uncertainty, recognition of task success is not always possible. The thesis considers the structure of backprojection regions and of task goals that ensures goal recognizability. The thesis also develops a representation of friction in configuration space, in terms of a friction cone analogous to the real space friction cone. The friction cone provides the backprojection algorithm with a geometrical tool for determining points at which motions may halt.

KInNeSS: A Modular Framework for Computational Neuroscience

Making use of very detailed neurophysiological, anatomical, and behavioral data to build biological-realistic computational models of animal behavior is often a difficult task. Until recently, many software packages have tried to resolve this mismatched granularity with different approaches. This paper presents KInNeSS, the KDE Integrated NeuroSimulation Software environment, as an alternative solution to bridge the gap between data and model behavior. This open source neural simulation software package provides an expandable framework incorporating features such as ease of use, scalabiltiy, an XML based schema, and multiple levels of granularity within a modern object oriented programming design. KInNeSS is best suited to simulate networks of hundreds to thousands of branched multu-compartmental neurons with biophysical properties such as membrane potential, voltage-gated and ligand-gated channels, the presence of gap junctions of ionic diffusion, neuromodulation channel gating, the mechanism for habituative or depressive synapses, axonal delays, and synaptic plasticity. KInNeSS outputs include compartment membrane voltage, spikes, local-field potentials, and current source densities, as well as visualization of the behavior of a simulated agent. An explanation of the modeling philosophy and plug-in development is also presented. Further developement of KInNeSS is ongoing with the ultimate goal of creating a modular framework that will help researchers across different disciplines to effecitively collaborate using a modern neural simulation platform.

KInNeSS: A Modular Framework for Computational Neuroscience

Making use of very detailed neurophysiological, anatomical, and behavioral data to build biologically-realistic computational models of animal behavior is often a difficult task. Until recently, many software packages have tried to resolve this mismatched granularity with different approaches. This paper presents KInNeSS, the KDE Integrated NeuroSimulation Software environment, as an alternative solution to bridge the gap between data and model behavior. This open source neural simulation software package provides an expandable framework incorporating features such as ease of use, scalability, an XML based schema, and multiple levels of granularity within a modern object oriented programming design. KInNeSS is best suited to simulate networks of hundreds to thousands of branched multi-compartmental neurons with biophysical properties such as membrane potential, voltage-gated and ligand-gated channels, the presence of gap junctions or ionic diffusion, neuromodulation channel gating, the mechanism for habituative or depressive synapses, axonal delays, and synaptic plasticity. KInNeSS outputs include compartment membrane voltage, spikes, local-field potentials, and current source densities, as well as visualization of the behavior of a simulated agent. An explanation of the modeling philosophy and plug-in development is also presented. Further development of KInNeSS is ongoing with the ultimate goal of creating a modular framework that will help researchers across different disciplines to effectively collaborate using a modern neural simulation platform.

A Spectral Network Model of Pitch Perception

A model of pitch perception, called the Spatial Pitch Network or SPINET model, is developed and analyzed. The model neurally instantiates ideas front the spectral pitch modeling literature and joins them to basic neural network signal processing designs to simulate a broader range of perceptual pitch data than previous spectral models. The components of the model arc interpreted as peripheral mechanical and neural processing stages, which arc capable of being incorporated into a larger network architecture for separating multiple sound sources in the environment. The core of the new model transforms a spectral representation of an acoustic source into a spatial distribution of pitch strengths. The SPINET model uses a weighted "harmonic sieve" whereby the strength of activation of a given pitch depends upon a weighted sum of narrow regions around the harmonics of the nominal pitch value, and higher harmonics contribute less to a pitch than lower ones. Suitably chosen harmonic weighting functions enable computer simulations of pitch perception data involving mistuned components, shifted harmonics, and various types of continuous spectra including rippled noise. It is shown how the weighting functions produce the dominance region, how they lead to octave shifts of pitch in response to ambiguous stimuli, and how they lead to a pitch region in response to the octave-spaced Shepard tone complexes and Deutsch tritones without the use of attentional mechanisms to limit pitch choices. An on-center off-surround network in the model helps to produce noise suppression, partial masking and edge pitch. Finally, it is shown how peripheral filtering and short term energy measurements produce a model pitch estimate that is sensitive to certain component phase relationships.

The impact of conifer plantation forestry on the ecology of peatland lakes

Blanket bog lakes are a characteristic feature of blanket bog habitats and harbour many rare and threatened invertebrate species. Despite their potential conservation value, however, very little is known about their physico-chemical or biological characteristics in western Europe, and their reference conditions are still unknown in Ireland. Furthermore, they are under considerable threat in Ireland from a number of sources, particularly afforestation of their catchments by exotic conifers. Plantation forestry can potentially lead to the increased input of substances including hydrogen ions (H+), plants nutrients, dissolved organic carbon (DOC), heavy metals and sediment. The aims of this study were to investigate the effect of conifer plantation forestry on the hydrochemistry and ecology of blanket bog lakes in western Ireland. Lake hydrochemistry, littoral Chydoridae (Cladocera) and littoral macroinvertebrate communities were compared among replicate lakes selected from three distinct catchment land use categories: i) unplanted blanket bog only present in the catchment, ii) mature (closed-canopy) conifer plantation forests only present in the catchment and iii) catchments containing mature conifer plantation forests with recently clearfelled areas. All three catchment land uses were replicated across two geologies: sandstone and granite. Lakes with afforested catchments across both geologies had elevated concentrations of phosphorus (P), nitrogen (N), total dissolved organic carbon (TDOC), aluminium (Al) and iron (Fe), with the highest concentrations of each parameter recorded from lakes with catchment clearfelling. Dissolved oxygen concentrations were also significantly reduced in the afforested lakes, particularly the clearfell lakes. This change in lake hydrochemistry was associated with profound changes in lake invertebrate communities. Within the chydorid communities, the dominance of Alonopsis elongata in the unplanted blanket bog lakes shifted to dominance by the smaller bodied Chydorus sphaericus, along with Alonella nana, Alonella excisa and Alonella exigua, in the plantation forestry-affected lakes, consistent with a shift in lake trophy. Similarly, there was marked changes in the macroinvertebrate communities, especially for the Coleoptera and Heteroptera assemblages which revealed increased taxon richness and abundance in the nutrient-enriched lakes. In terms of conservation status, despite having the greatest species-quality scores (SQS) and species richness, three of the four International Union for the Conservation of Nature (IUCN) red-listed species of Coleoptera and Odonata recorded during the study were absent from lakes subject to catchment clearfelling. The relative strengths of bottom-up (forestry-mediated nutrient enrichment) and top-down (fish) forces in structuring littoral macroinvertebrate communities was investigated in a separate study. Nutrient enrichment was shown to be the dominant force acting on communities, with fish having a lesser influence. These results confirmed that plantation forestry poses the single greatest threat to the conservation status of blanket bog lakes in western Ireland. The findings of this study have major implications for the management of afforested peatlands. Further research is required on blanket bog lakes to prevent any further plantation forestry-mediated habitat deterioration of this rare and protected habitat.

The environmental justice dimensions of climate change

Nations around the world are considering strategies to mitigate the severe impacts of climate change predicted to occur in the twenty-first century. Many countries, however, lack the wealth, technology, and government institutions to effectively cope with climate change. This study investigates the varying degrees to which developing and developed nations will be exposed to changes in three key variables: temperature, precipitation, and runoff. We use Geographic Information Systems (GIS) analysis to compare current and future climate model predictions on a country level. We then compare our calculations of climate change exposure for each nation to several metrics of political and economic well-being. Our results indicate that the impacts of changes in precipitation and runoff are distributed relatively equally between developed and developing nations. In contrast, we confirm research suggesting that developing nations will be affected far more severely by changes in temperature than developed nations. Our results also suggest that this unequal impact will persist throughout the twenty-first century. Our analysis further indicates that the most significant temperature changes will occur in politically unstable countries, creating an additional motivation for developed countries to actively engage with developing nations on climate mitigation strategies. © 2011, Mary Ann Liebert, Inc.