Dynamic Binding Mechanism Research Articles

A duty based approach in solving the aircrew recovery problem

This paper eliminates the step of rotation generation to allow the crew recovery problem to be dealt with directly in relation to flight legs. A duty based GA model with a dynamic leg binding mechanism is developed to solve the crew recovery problem. This is about hundred times faster than the traditional process, a feature possible by introducing the original crew schedule as the initial solution. This model is applied to an international airline in Taiwan and the results compared to previous studies.

Running Mechanism and Strategy Description Language SADL for Self-Adaptive MAS

PDF HTML阅读 XML下载 导出引用 引用提醒 自适应多Agent 系统的运行机制和策略描述语言SADL DOI: 10.3724/SP.J.1001.2011.03762 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金(60773018, 90818028); 国家高技术研究发展计划(863)(2007AA01Z135); 国家重点基础研究发展计划(973)(2005CB321802) Running Mechanism and Strategy Description Language SADL for Self-Adaptive MAS Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:自适应系统具有环境开放性、变化敏感性、系统动态性等复杂性特点,如何支持这类复杂系统的开发和维护是目前软件工程关注的焦点.将自适应系统中的自主运行单元抽象为软件Agent,借助组织学思想提出了支持自适应系统运行的动态绑定机制,设计了表述Agent 如何适应环境变化的自适应策略描述语言SADL(self-adaptive strategy description language),开发了SADL 的编译器和运行支撑环境.该方法将复杂自适应系统的自适应逻辑和业务逻辑相分离,通过SADL 语言显式地描述系统的自适应特征,从而简化了复杂自适应系统的开发和维护.通过案例分析,阐述了如何基于上述方法来进行复杂自适应系统的开发,验证了方法的有效性. Abstract:Self-Adaptive systems have many complex properties such as openness in a situated environment, sensibility to changes, and dynamic of a system. Finding ways to develop such complex systems is still a problem in the literature of software engineering. In this paper, the autonomous entities in self-adaptive systems are abstracted as software agents, and the dynamic binding mechanism for self-adaptation is proposed based on the organization metaphors. A self-adaptive strategy description language called SADL (self-adaptive strategy description language) is presented to describe adaptive strategies that express how agents adapt to the changes. The complier and operating environment for SADL have been developed. This approach enables developers to separate the adaptation logic from functional logic of self-adaptive systems and explicitly describe self-adaptation in order to simplify the development and maintenance of complex self-adaptive systems. This case is studied in detail to illustrate the effectiveness of this proposed approach. 参考文献 相似文献 引证文献

On the use of metatypes for safe embedded operating system extension

We present in this paper an extensible system for small secure embedded devices. We advocate the use of a typed intermediate language as a transformation of various high level languages. We present an extensible type system that unifies in a unique hierarchy some type systems from various source languages and ensures integrity and confidentility. To increase execution efficiency and use flexibility, we propose a dynamic binding mechanism that allows the programmer to describe the bindings of his code without breaking the type system. We also design the whole type system so that future addition of new kinds of objects has as little impact as possible.

DynaFlow: a dynamic inter-organisational workflow management system

As the global marketplace becomes more and more competitive, business organisations often need to team up and operate as a virtual enterprise to utilise the best of their resources for achieving their common business goals. As the business environment of a virtual enterprise is highly dynamic, it is necessary to develop a workflow management technology that is capable of handling dynamic workflows across enterprise boundaries. This paper describes a Dynamic Workflow Model (DWM) and a dynamic workflow management system (DynaFlow) for modelling and controlling the execution of inter-organisational business processes. DWM enables the specification of dynamic properties associated with a business process model. It extends the underlying model of the WfMC's WPDL by adding connectors, events, triggers and rules as its modelling constructs. It also encapsulates activity definitions and allows web service (or e-service) requests to be included as a part of the activity specification. Using DWM as the underlying model, DynaFlow makes use of an Event-Trigger-Rule (ETR) server to trigger rules during the enactment of a workflow process to enforce business rules and policies and/or to modify the process model at run-time. A constraint-based, dynamic service binding mechanism is used to dynamically bind web service requests to web services that satisfy the requirements of the requests.

Comparative Agonist/Antagonist Responses in Mutant Human C5a Receptors Define the Ligand Binding Site

The C terminus is responsible for all of the agonist activity of C5a at human C5a receptors (C5aRs). In this report we have mapped the ligand binding site on the C5aR using a series of agonist and antagonist peptide mimics of the C terminus of C5a as well as receptors mutated at putative interaction sites (Ile(116), Arg(175,) Arg(206), Glu(199), Asp(282), and Val(286)). Agonist peptide 1 (Phe-Lys-Pro-d-cyclohexylalanine-cyclohexylalanine-d-Arg) can be converted to an antagonist by substituting the bulkier Trp for cyclohexylalanine at position 5 (peptide 2). Conversely, mutation of C5aR transmembrane residue Ile(116) to the smaller Ala (I116A) makes the receptor respond to peptide 2 as an agonist (Gerber, B. O., Meng, E. C., Dotsch, V., Baranski, T. J., and Bourne, H. R. (2001) J. Biol. Chem. 276, 3394-3400). However, a potent cyclic hexapeptide antagonist, Phe-cyclo-[Orn-Pro-d-cyclohexylalanine-Trp-Arg] (peptide 3), derived from peptide 2 and which binds to the same receptor site, remains a full antagonist at I116AC5aR. This suggests that although the residue at position 5 might bind near to Ile(116), the latter is not essential for either activation or antagonism. Arg(206) and Arg(175) both appear to interact with the C-terminal carboxylate of C5a agonist peptides, suggesting a dynamic binding mechanism that may be a part of a receptor activation switch. Asp(282) has been previously shown to interact with the side chain of the C-terminal Arg residue, and Glu(199) may also interact with this side chain in both C5a and peptide mimics. Using these interactions to orient NMR-derived ligand structures in the binding site of C5aR, a new model of the interaction between peptide antagonists and the C5aR is presented.

Dynamic Inter-Enterprise Workflow Management in a Constraint-Based E-Service Infrastructure

This paper presents an infrastructure and a mechanism for achieving dynamic Inter-enterprise workflow management using e-services provided by collaborative e-business enterprises. E-services are distributed services that can be accessed programmatically on the Internet, using SOAP messages and the HTTP protocol. In this work, we categorize e-services according to their business types and manage them in a UDDI-enabled constraint-based Broker Server. E-service requests are specified in the activities of a process model according to some standardized e-service templates and are bound to the proper service providers at run-time by using a constraint-based, dynamic service binding mechanism. The workflow management system is dynamic in the sense that the actual business organizations, which take part in a business process, are not determined until run-time. We have extended the traditional workflow process modeling by including e-service requests in activity specifications and extended the Web Service Description Language (WSDL) by including constraints in both service specifications and service requests so that the selection of e-service providers can be more accurately performed.

Foldamers as dynamic receptors: probing the mechanism of molecular association between helical oligomers and rodlike ligands.

A dynamic binding mechanism allows the association of dumbbell-shaped ligand 2 with helical folded oligo(m-phenyleneethynylene)s 1 (see schematic representation). Association constants are oligomer length specific, with a maximum value for the icosamer and docosamer. These oligomers have helical conformations that are highly shape-complementary to 1; shorter and longer oligomers exhibit association constants roughly an order of magnitude smaller.

Extension of the temporal synchrony approach to dynamic variable bindingin a connectionist inference system

The relationship between symbolism and connectionism has been one of the major issues in recent artificial intelligence research. An increasing number of researchers from each side have tried to adopt the desirable characteristics of the approach. A major open question in this field is the extent to which a connectionist architecture can accommodate basic concepts of symbolic inference, such as a dynamic variable binding mechanism and a rule and fact encoding mechanism involving nary predicates. One of the current leaders in this area is the connectionist rule-based system proposed by Shastri and Ajjanagadde. The paper demonstrates that the mechanism for variable binding which they advocate is fundamentally limited, and it shows how a reinterpretation of the primitive components and corresponding modifications of their system can extend the range of inference which can be supported. Our extension hinges on the basic structural modification of the network components and further modifications of the rule and fact encoding mechanism. These modifications allow the extended model to have more expressive power in dealing with symbolic knowledge as in the unification of terms across many groups of unifying arguments.