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31.
An Internet-based negotiation server for e-commerce 总被引:6,自引:0,他引:6
Stanley Y.W. Su Chunbo Huang Joachim Hammer Yihua Huang Haifei Li Liu Wang Youzhong Liu Charnyote Pluempitiwiriyawej Minsoo Lee Herman Lam 《The VLDB Journal The International Journal on Very Large Data Bases》2001,10(1):72-90
This paper describes the design and implementation of a replicable, Internet-based negotiation server for conducting bargaining-type
negotiations between enterprises involved in e-commerce and e-business. Enterprises can be buyers and sellers of products/services
or participants of a complex supply chain engaged in purchasing, planning, and scheduling. Multiple copies of our server can
be installed to complement the services of Web servers. Each enterprise can install or select a trusted negotiation server
to represent his/her interests. Web-based GUI tools are used during the build-time registration process to specify the requirements,
constraints, and rules that represent negotiation policies and strategies, preference scoring of different data conditions,
and aggregation methods for deriving a global cost-benefit score for the item(s) under negotiation. The registration information
is used by the negotiation servers to automatically conduct bargaining type negotiations on behalf of their clients. In this
paper, we present the architecture of our implementation as well as a framework for automated negotiations, and describe a
number of communication primitives which are used in the underlying negotiation protocol. A constraint satisfaction processor
(CSP) is used to evaluate a negotiation proposal or counterproposal against the registered requirements and constraints of
a client company. In case of a constraint violation, an event is posted to trigger the execution of negotiation strategic
rules, which either automatically relax the violated constraint, ask for human intervention, invoke an application, or perform
other remedial operations. An Event-Trigger-Rule (ETR) server is used to manage events, triggers, and rules. Negotiation strategic
rules can be added or modified at run-time. A cost-benefit analysis component is used to perform quantitative analysis of
alternatives. The use of negotiation servers to conduct automated negotiation has been demonstrated in the context of an integrated
supply chain scenario.
Received: 30 October 2000 / Accepted: 12 January 2001 Published online: 2 August 2001 相似文献
32.
Furstenberg R Kendziora CA Stepnowski SV McGill RA 《The Review of scientific instruments》2007,78(6):064903
We report a new experimental apparatus for infrared microthermography applicable to a wide class of samples including semitransparent ones and perforated devices. This setup is particularly well suited for the thermography of microfabricated devices. Traditionally, temperature calibration is performed using calibration hot plates, but this is not applicable to transmissive samples. In this work a custom designed miniature calibration oven in conjunction with spatial filtering is used to obtain accurate static and transient temperature maps of actively heated devices. The procedure does not require prior knowledge of the emissivity. Calibration and image processing algorithms are discussed and analyzed. We show that relatively inexpensive uncooled bolometer arrays can be a suitable detector choice in certain radiometric applications. As an example, we apply this method in the analysis of temperature profiles of an actively heated microfabricated preconcentrator device that incorporates a perforated membrane and is used in trace detection of illicit substances. 相似文献
33.
Business Object Modeling, Validation, and Mediation for Integrating Heterogeneous Application Systems 总被引:1,自引:0,他引:1
When different business organizations come together to conduct a joint business in a virtual enterprise environment, their application systems need to have a convenient way to specify the services needed from other systems and to transfer data needed by these services. The transferred data needs to be validated and, in some cases, mediated to meet the constraints and data representation requirements of both the source and target application systems. Ideally, the validation and mediation tasks should be done outside of the legacy application systems so that these systems do not have to be modified. In this work, the Business Object Documents (BODs) introduced by the Open Applications Group (OAG) are used for specifying business operations and transferring data among application systems. We use an active object model to model BODs. The model captures not only the data attributes and methods associated with these business objects, but also events and rules for specifying and triggering the enforcement of attribute constraints and inter-attribute constraints and the activation of data mediation operations. The conceptual models of these BODs with their added semantics are used to generate entity classes, converters and skeletal programs needed for enforcing constraints and for converting data. These generated object classes and software components in Java constitute the platform-independent adapters through which heterogeneous application systems inter-operate over CORBA and RMI communication infrastructures. A distributed approach to data validation and mediation is used. It allows the generated code for validation and mediation to be distributed and processed at different sites, thus avoiding the potential network bottleneck of a centralized approach to the validation and mediation of business object documents. 相似文献
34.
Kenneth O. Stanley 《Genetic Programming and Evolvable Machines》2007,8(2):131-162
Natural DNA can encode complexity on an enormous scale. Researchers are attempting to achieve the same representational efficiency
in computers by implementing developmental encodings, i.e. encodings that map the genotype to the phenotype through a process of growth from a small starting point to a mature
form. A major challenge in in this effort is to find the right level of abstraction of biological development to capture its
essential properties without introducing unnecessary inefficiencies. In this paper, a novel abstraction of natural development,
called Compositional Pattern Producing Networks (CPPNs), is proposed. Unlike currently accepted abstractions such as iterative
rewrite systems and cellular growth simulations, CPPNs map to the phenotype without local interaction, that is, each individual
component of the phenotype is determined independently of every other component. Results produced with CPPNs through interactive
evolution of two-dimensional images show that such an encoding can nevertheless produce structural motifs often attributed
to more conventional developmental abstractions, suggesting that local interaction may not be essential to the desirable properties
of natural encoding in the way that is usually assumed.
相似文献
Kenneth O. StanleyEmail: |
35.
SV Buldyrev AL Goldberger S Havlin Peng C-K M Simons HE Stanley 《Canadian Metallurgical Quarterly》1993,47(6):4514-4523
We propose a generalized Lévy walk to model fractal landscapes observed in noncoding DNA sequences. We find that this model provides a very close approximation to the empirical data and explains a number of statistical properties of genomic DNA sequences such as the distribution of strand-biased regions (those with an excess of one type of nucleotide) as well as local changes in the slope of the correlation exponent alpha. The generalized Lévy-walk model simultaneously accounts for the long-range correlations in noncoding DNA sequences and for the apparently paradoxical finding of long subregions of biased random walks (length lj) within these correlated sequences. In the generalized Lévy-walk model, the lj are chosen from a power-law distribution P(lj) varies as lj(-mu). The correlation exponent alpha is related to mu through alpha = 2-mu/2 if 2 < mu < 3. The model is consistent with the finding of "repetitive elements" of variable length interspersed within noncoding DNA. 相似文献
36.
Hall Gordon C. Nagayama; Teten Andra L.; DeGarmo David S.; Sue Stanley; Stephens Kari A. 《Canadian Metallurgical Quarterly》2005,73(5):830
Explanatory models of sexual aggression were examined among mainland Asian American (n = 222), Hawaiian Asian American (n = 127), and European American men (n = 399). The Malamuth et al. (N. M. Malamuth, D. Linz, C. L. Heavey, G. Barnes, & M. Acker, 1995; N. M. Malamuth, R. J. Sockloskie, M. P. Koss, & J. S. Tanaka, 1991) confluence model of sexual aggression, which posits impersonal sex and hostile masculinity as paths to sexual aggression, was consistently supported. Culture-specific moderators of sexual aggression were also identified. Whereas loss of face was a protective factor against sexual aggression in the Asian American samples, it generally was not a protective factor among European Americans. These findings are not a function of actual or perceived minority status. An implication is that theoretical models may need to be augmented with cultural constructs for optimal application in certain ethnic group contexts. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
37.
Personalcasting: Tailored Broadcast News 总被引:1,自引:0,他引:1
Maybury Mark Greiff Warren Boykin Stanley Ponte Jay McHenry Chad Ferro Lisa 《User Modeling and User-Adapted Interaction》2004,14(1):119-144
Broadcast news sources and newspapers provide society with the vast majority of real-time information. Unfortunately, cost efficiencies and real-time pressures demand that producers, editors, and writers select and organize content for stereotypical audiences. In this article we illustrate how content understanding, user modeling, and tailored presentation generation promise personalcasts on demand. Specifically, we report on the design and implementation of a personalized version of a broadcast news understanding system, MITRE’s Broadcast News Navigator (BNN), that tracks and infers user content interests and media preferences. We report on the incorporation of Local Context Analysis to both expand the user’s original query to the most related terms in the corpus, as well as to allow the user to provide interactive feedback to enhance the relevance of selected newsstories. We describe an empirical study of the search for stories on ten topics from a video corpus. By personalizing both the selection of stories and the form in which they are delivered, we provide users with tailored broadcast news. This individual news personalization provides more fine-grained content tailoring than current personalized television program level recommenders and does not rely on externally provided program metadata. 相似文献
38.
Contends that the glory of psychotherapists' "tree of psychology" is that its roots are absolutely philosophical and, therefore, limitless in scope and devoid of absolute proofs. The trunk of this tree is a solid and substantial store of scientific and empirical data. The branches bear a multitude of flowers, many of which are not quite substantial; not made to endure the critical climate of a questioning world. Ultimately, however, these flowers contain the germinating factor, that which allows human knowledge the possibility of continued growth and rejuvenation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
39.
The paper reports an investigation of managerial stress in Singapore. From two quasi-government bodies, 142 male managers volunteered as subjects. Their demographics, perception of their job and organization, and their personality (using Cattell's 16PF) were measured. The dependent variables were psychological ill-health (anxiety score from 16PF) and physical ill-health (using Gurin's Psychosomatic Symptom List). Managers were compared across levels and across functional areas. Lower level managers were found to exhibit higher anxiety than middle level managers (p < 0.05) but their functional activity had no significant effect on stress intensity. Managers in the 35–45 years age group experienced significantly higher physical ill-health than all other managers (p < 0.05). All of the anxiety-prone personality traits (eg., shyness, uncontrolled self-concept, and introversion) had a significant relationship with ill-health (at least p < 0.03). A comparison with data from the UK revealed important cross-cultural differences. It is concluded that stress prevention and stress coping strategies need to be specific to Singapore, and that increased participation in the decision-making process will reduce managerial stress. 相似文献
40.