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1.
Requirement emergence computation of networked software   总被引:3,自引:0,他引:3  
Emergence Computation has become a hot topic in the research of complex systems in recent years. With the substantial increase in scale and complexity of network-based information systems, the uncertain user requirements from the Internet and personalized application requirement result in the frequent change for the software requirement. Meanwhile, the software system with non self-possessed resource become more and more complex. Furthermore, the interaction and cooperation requirement between software units and running environment in service computing increase the complexity of software systems. The software systems with complex system characteristics are developing into the “Networked Software” with characteristics of change-on-demand and change-with-cooperation. The concepts “programming”, “compiling” and “running” of software in common sense are extended from “desktop” to “network”. The core issue of software engineering is moving to the requirement engineering, which becomes the research focus of complex system software engineering. In this paper, we present the software network view based on complex system theory, and the concept of networked software and networked requirement. We propose the challenge problem in the research of emergence computation of networked software requirement. A hierarchical & cooperative unified requirement modeling framework URF (Unified Requirement Framework) and related RGPS (Role, Goal, Process and Service) meta-models are proposed. Five scales and the evolutionary growth mechanism in requirement emergence computation of networked software are given with focus on user-dominant and domain-oriented requirement, and the rules and predictability in requirement emergence computation are analyzed. A case study in the application of networked e-Business with evolutionary growth based on State design pattern is presented in the end.  相似文献   

2.
A new droplet-driving scheme for digital microfluidics termed the “pre-charging of a droplet” is demonstrated. In this method, a droplet is initially charged by applying “pre-charging” voltage between the droplet and an electrode buried under dielectric layers. The droplet is then driven to the next electrode by applying “driving” voltage between two adjacent buried electrodes. The concept of pre-charging was proved by the polarity of the charge stored in the droplet. When the droplet is pre-charged with positive voltage, it is driven with negative voltage and vice versa. Therefore, the magnitudes of the pre-charging and driving voltages are identical, but only with the opposite polarity. A 2.5-μL deionized water droplet is pre-charged and driven at a minimal voltage of 12 V. The charge stored in the droplet by this pre-charging method remained for more than 2 min, and the driving actuation could be repeated more than 150 times while the droplet remained its charged state. This method suggests a new means of driving a droplet for digital microfluidics at a relatively low voltage by utilizing both the electrostatic and dielectrophoretic force in the droplet transport process with a simpler structure compared to other single-plate structured devices.  相似文献   

3.
This paper describes an attempt to implement a complex information technology system with the New York City Transit Authority’s (NYCTA) Bus Maintainers intended to help better track and coordinate bus maintenance schedules. IT implementation is notorious for high failure rates among so-called “low level” workers. We believe that many IT implementation efforts make erroneous assumptions about front line worker’s expertise, which creates tension between the IT implementation effort and the “cultures of practice” among the front line workers. We designed an aggressive “learning intervention” to address this issue and called “Operational Simulation”. Rather than requiring the expected 12 months for implementation, the hourly staff reached independence with the new system in 2 weeks and line supervisors (who do more) managed in 6 weeks. Additionally, the NYCTA shifted from a reactive to a proactive maintenance approach, reduced cycle times, and increased the “mean distance between failure”, resulting in a estimated $40 million cost savings. Implications for cognition, expertise, and training are discussed.  相似文献   

4.
Using few very general axioms which should be satisfied by any reasonable theory consistent with the Second Law of Thermodynamics we argue that: a) “no-cloning theorem” is meaningful for a very general theoretical scheme including both quantum and classical models, b) in order to describe self-replication, Wigner’s “cloning” process should be replaced by a more general “broadcasting”, c) “separation of species” is possible only in a non-homogeneous environment, d) “parent” and “offspring” must be strongly correlated. Motivated by the existing results on broadcasting which show that only classical information can self-replicate perfectly we discuss briefly a classical toy model with “quantum features” — overlapping pure states and “entangled states” for composite systems.  相似文献   

5.
Conclusion In the models of passive-state formation considered above we have assumed for simplicity constant control parameters. In reality, the control parameters are functions of time, environmental factors, and the values of the “active” variables [7, 8]. These functions are “reasonably” constructed: under “bad” conditions the variables shift to a passive state, and when “good” conditions are restored, the variables switch back to active state. It is relevant to develop and analyze the corresponding model circuits. Here we can expect to observe even stronger stabilization effects in the behavior of complex systems. In conclusion, I would like to thank an anonymous referee for useful comments. The study is financed by the Russian Foundation of Basic Research. Translated from Kibernetika i Sistemnyi Analiz, No. 6, pp. 103–112, November–December, 1995.  相似文献   

6.
Erik Hollnagel’s body of work in the past three decades has molded much of the current research approach to system safety, particularly notions of “error”. Hollnagel regards “error” as a dead-end and avoids using the term. This position is consistent with Rasmussen’s claim that there is no scientifically stable category of human performance that can be described as “error”. While this systems view is undoubtedly correct, “error” persists. Organizations, especially formal business, political, and regulatory structures, use “error” as if it were a stable category of human performance. They apply the term to performances associated with undesired outcomes, tabulate occurrences of “error”, and justify control and sanctions through “error”. Although a compelling argument can be made for Hollnagel’s view, it is clear that notions of “error” are socially and organizationally productive. The persistence of “error” in management and regulatory circles reflects its value as a means for social control.  相似文献   

7.
As it was shown in Jenei and Montagna (Studia Logica 70(2): 183–192, 2002), Monoidal t-norm based logic (MTL) is a logic of left-continuous t-norms. In other words, this means that MTL enjoys the standard completeness theorem. In this paper we present a different proof of this theorem. In fact, we prove even more since we show that MTL is complete w.r.t. the class of standard MTL-algebras with finite congruence lattice or equivalently with finitely many Archimedean classes. We also show the connection between the congruence lattice of an MTL-chain and its Archimedean classes.The author was supported by the Program “Information Society” under project 1ET100300517.  相似文献   

8.
This paper proposes a novel approach to the analysis and validation of mathematical models using two-dimensional geometrical patterns representing parameter-parameter dependencies (PPD) in dynamic systems. A geometrical pattern is obtained by calculating moment values, such as the area under the curve (AUC), area under the moment curve (AUMC), and mean residence time (MRT), for a series of simulations with a wide range of parameter values. In a mathematical model of the metabolic pathways of the cancer drug irinotecan (CPT11), geometrical patterns can be classified into three major categories: “independent,” “hyperbolic,” and “complex.” These categories characterize substructures arising in differential equations, and are helpful for understanding the behavior of large-scale mathematical models. The Open Bioinformatics Grid (OBIGrid) provides a cyber-infrastructure for users to share these data as well as computational resources.  相似文献   

9.
We compare two physical systems: polarization degrees of freedom of a macroscopic light beam and the Josephson junction (JJ) in the “charge qubit regime”. The first system obviously cannot carry genuine quantum information and we show that the maximal entanglement which could be encoded into polarization of two light beams scales like 1/(photon number). Two theories of JJ, one leading to the picture of “JJ-qubit” and the other based on the mean-field approach are discussed. The later, which seems to be more appropriate, implies that the JJ system is, essentially, mathematically equivalent to the polarization of a light beam with the number of photons replaced by the number of Cooper pairs. The existing experiments consistent with the “JJ-qubit” picture and the theoretical arguments supporting, on the contrary, the classical model are briefly discussed. The Franck-Hertz-type experiment is suggested as an ultimate test of the JJ nature.  相似文献   

10.
We explore in this paper how performance of e-commerce websites in terms of various criteria influences customers’ intention to shop again in the same website. Our approach is based on an interesting use of statistical regression in the hotel literature that attempted to classify different cues in hotels as critical, satisfier, dissatisfier, etc. We use online ratings for 484 e-commerce websites for this study. Our study shows that “satisfaction with claims” is the single most important criterion valued as critical by online customers. “Comparative prices” and “Refunds/returns” are desirable criteria. “Management accessibility”, “Payment process” and “Privacy experience” are satisfiers while “on-time delivery” is a dissatisfier.  相似文献   

11.
The existing anti-HIV-1 drugs have troublesome problems with side-effects and the development of drug resistance, etc. To avoid these problems by using our knowledge of complex network analyses, this study examines the topological conditions needed for a satisfactory anti-HIV-1 drug target, and suggests that a promising anti-HIV-1 drug target should be endowed with the features of a “hub” and a “bottleneck” in the HIV-1 proteins-intracellular agent interaction network.  相似文献   

12.
We present a new approach to the tracking of very non-rigid patterns of motion, such as water flowing down a stream. The algorithm is based on a “disturbance map”, which is obtained by linearly subtracting the temporal average of the previous frames from the new frame. Every local motion creates a disturbance having the form of a wave, with a “head” at the present position of the motion and a historical “tail” that indicates the previous locations of that motion. These disturbances serve as loci of attraction for “tracking particles” that are scattered throughout the image. The algorithm is very fast and can be performed in real time. We provide excellent tracking results on various complex sequences, using both stabilized and moving cameras, showing a busy ant column, waterfalls, rapids and flowing streams, shoppers in a mall, and cars in a traffic intersection. Received: 24 June 1997 / Accepted: 30 July 1998  相似文献   

13.
Inter-organizational networks for knowledge sharing and trading   总被引:1,自引:1,他引:0  
Although companies are increasingly developing complex networks of connections with their partners and customers and shifting their focus towards expanding the knowledge management concept externally, research addressing the management of knowledge across organizational borders is rather sparse. Our aim in the present paper is to develop a typology of cross-organizational networks of information and knowledge flows. In order to arrive at such a typology we examine two issues. The first concerns the locus of control on the processes that enable knowledge flow. The second refers to the tradability of the streams of knowledge that flow among organizational entities. We examine four types of knowledge networks: “knowledge communities”, “knowledge chains”, “knowledge supplies” and “knowledge markets”. For each type of knowledge network, we examine its distinct characteristics, study related examples, consider the associated research challenges and analyze an indicative case.  相似文献   

14.
ExploreNet is an experimental environment for creating and delivering networked “virtual worlds.” This system's style of user interaction was inspired by the concept of a “habitat” as first articulated in the LucasFilm's Habitat system. Players enter and interact in a habitat via their animated alter egos, called “avatars.” Habitats may be created for many purposes, including social interaction, entertainment and education. Our focus has been to facilitate the creation of habitats in which virtual communities of learners and mentors interact. This paper presents details of the current ExploreNet system, including its user interface, the means it provides for creating complex behaviors, details of its implementation, the outcomes of several experiments using this system, and our plans for its natural migration to a World Wide Web-based system.  相似文献   

15.
BOSS QUATTRO: an open system for parametric design   总被引:1,自引:0,他引:1  
During the two past decades, engineers have shown growing interest in automatic structural optimization techniques. These were first used to solve analytical problems and were then rapidly adapted to structural sizing problems coupled to finite element analysis software. Moreover, shape optimization problems featuring complex CAD systems were addressed in the early 90’s. This article describes the capabilities of the optimization product developed by SAMTECH S.A. in Liège, Belgium. One will read here what led the company and a group of research engineers at LTAS (Laboratoire des Techniques Aéronautiques et Spatiales, Université de Liège) to the achievement of a so-called open system for parametric design. The BOSS/Quattro package is a general-purpose design program. It includes several “engines”: optimization, parametric studies, “Monte-Carlo” studies, “design of experiments” and updating. It is interesting to note that the “engines” can be easily mixed through the graphical user interface (GUI), and, this, with several analysis models. Received December 30, 2000  相似文献   

16.
In recent years, on-demand transport systems (such as a demand-bus system) are focused as a new transport service in Japan. An on-demand vehicle visits pick-up and delivery points by door-to-door according to the occurrences of requests. This service can be regarded as a cooperative (or competitive) profit problem among transport vehicles. Thus, a decision-making for the problem is an important factor for the profits of vehicles (i.e., drivers). However, it is difficult to find an optimal solution of the problem, because there are some uncertain risks, e.g., the occurrence probability of requests and the selfishness of other rival vehicles. Therefore, this paper proposes a transport policy for on-demand vehicles to control the uncertain risks. First, we classify the profit of vehicles as “assured profit” and “potential profit”. Second, we propose a “profit policy” and “selection policy” based on the classification of the profits. Moreover, the selection policy can be classified into “greed”, “mixed”, “competitive”, and “cooperative”. These selection policies are represented by selection probabilities of the next visit points to cooperate or compete with other vehicles. Finally, we report simulation results and analyze the effectiveness of our proposal policies.  相似文献   

17.
18.
This paper describes new “lemma” and “cut” strategies that are efficient to apply in the setting of propositional Model Elimination. Previous strategies for managing lemmas and C-literals in Model Elimination were oriented toward first-order theorem proving. The original “cumulative” strategy remembers lemmas forever, and was found to be too inefficient. The previously reported C-literal and unit-lemma strategies, such as “strong regularity”, forget them unnecessarily soon in the propositional domain. An intermediate strategy, called “quasi-persistent” lemmas, is introduced. Supplementing this strategy, methods for “eager” lemmas and two forms of controlled “cut” provide further efficiencies. The techniques have been incorporated into “Modoc”, which is an implementation of Model Elimination, extended with a new pruning method that is designed to eliminate certain refutation attempts that cannot succeed. Experimental data show that on random 3CNF formulas at the “hard” ratio of 4.27 clauses per variable, Modoc is not as effective as recently reported model-searching methods. However, on more structured formulas from applications, such as circuit-fault detection, it is superior. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

19.
With the recent trend to model driven engineering a common understanding of basic notions such as “model” and “metamodel” becomes a pivotal issue. Even though these notions have been in widespread use for quite a while, there is still little consensus about when exactly it is appropriate to use them. The aim of this article is to start establishing a consensus about generally acceptable terminology. Its main contributions are the distinction between two fundamentally different kinds of model roles, i.e. “token model” versus “type model” (The terms “type” and “token” have been introduced by C.S. Peirce, 1839–1914.), a formal notion of “metaness”, and the consideration of “generalization” as yet another basic relationship between models. In particular, the recognition of the fundamental difference between the above mentioned two kinds of model roles is crucial in order to enable communication among the model driven engineering community that is free of both unnoticed misunderstandings and unnecessary disagreement.  相似文献   

20.
The universal technique of finding optimum training parameters for multi-layer perceptron—such as percentage of samples in a cross-validation set and quantities of training iterations with various initial values—is offered. This technique is aimed at the searching of optimum values of two complex factors depending on accuracy and convergence of a network, and also on the time of its training. Their conventional names are “cross-validation coefficient” and “training iteration coefficient”. Near infrared spectroscopy data for gasoline samples are used to evaluate the efficiency of the method.  相似文献   

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