An integrated protocol stack for efficient resources management in wireless networks

The area of ATM multihop radio networks has recently become an issue of interest especially with the growing interest in portable multimedia units. Multimedia communication requires a deterministic delivery of isochronous traffic with predefined QoS requirements. In this paper we propose an integrated protocol stack which provides deterministic delivery bounds and efficiently utilizes channel backwidth. By integrating the access, routing and congestion control protocols, a solution is provided which improves bandwidth utilization, maintains shortest route packet delivery and leads to congestion avoidance. A tractable approximate analytical model is developed and verified for networks with finite storage capacity. For large multihop networks the analytical solution is complemented by simulation. Evaluation shows that the proposed protocol integration yields a significant reduction in end-to-end delay, which together with bounded access time at the channel access level, provide two essential features for the support of isochronous traffic in multihop wireless environments.     

The implications of the national curriculum for the use and management of IT resources in schools

Abstract  The introduction of a national curriculum in England, Wales and Northern Ireland is having a major effect on all schools. Information Technology is identified as a key area of this curriculum, not as a subject itself but as a theme which must permeate the curriculum. The implications are many and varied. An overview is provided of these issues, and indications given of the decisions that need to be made and the possible outcomes.     

System complexity and integrated diagnostics

An overview of a complete approach to integrated diagnostics is given. The approach is centered around an information-flow model and incorporates techniques from information fusion and artificial intelligence to guide analyses. The concept of integrated diagnosis is explained, and the model is examined. The authors show how to analyze testability, evaluate fault diagnosis, and create maintenance aids     

信息化资源的管理

孤立地考虑信息技术与商业价值，往往带来令人沮丧的结果，企业无法实现预期的利益，虽然我们无法确切地预知对信息技术的投入所带来的带来的利益，但我们能够确立企业战略发展目标、把握企业的管理需要，从而建立针对信息的管理需要，从而建立针对信息系统的相关资源：技术、资金、人员和时间的管理理念。     

An efficient job management of computing service using integrated idle VM resources for high-performance computing based on OpenStack

In recent years, various studies on OpenStack-based high-performance computing have been conducted. OpenStack combines off-the-shelf physical computing devices and creates a resource pool of logical computing. The configuration of the logical computing resource pool provides computing infrastructure according to the user’s request and can be applied to the infrastructure as a service (laaS), which is a cloud computing service model. The OpenStack-based cloud computing can provide various computing services for users using a virtual machine (VM). However, intensive computing service requests from a large number of users during large-scale computing jobs may delay the job execution. Moreover, idle VM resources may occur and computing resources are wasted if users do not employ the cloud computing resources. To resolve the computing job delay and waste of computing resources, a variety of studies are required including computing task allocation, job scheduling, utilization of idle VM resource, and improvements in overall job’s execution speed according to the increase in computing service requests. Thus, this paper proposes an efficient job management of computing service (EJM-CS) by which idle VM resources are utilized in OpenStack and user’s computing services are processed in a distributed manner. EJM-CS logically integrates idle VM resources, which have different performances, for computing services. EJM-CS improves resource wastes by utilizing idle VM resources. EJM-CS takes multiple computing services rather than single computing service into consideration. EJM-CS determines the job execution order considering workloads and waiting time according to job priority of computing service requester and computing service type, thereby providing improved performance of overall job execution when computing service requests increase.

     

Decision support for integrated cash management

Cash management has attracted the increasing attention of both academicians and practitioners in recent time. The expanding role and responsibilities of cash managers and corporate treasurers is likely to increase the focus on cash management as a vital organizational function. Academic research, however, has primarily focused on providing analytical tools to solve well structured problems that are relatively isolated in nature. Conspicuously, no attempt has been made to integrate the various sub-problems of cash management explicitly recognizing interrelationships among the sub-problems as well as between the sub-problems and other financial decisions. More importantly, there is an even greater need to provide a framework that in addition to recognizing the above interrelationships will enable the cash manager to recognize a more inclusive set of dependencies that exist in practice.Decision support systems have the potential to overcome the above deficiencies to a significant extent. This paper is aimed at providing a conceptual framework for designing an effective model-based decision support system (DSS) for integrated cash management. The framework should form a useful basis for any attempts at designing computer-based support systems for cash management.     

Information management for integrated design environments

This paper identifies requirements for an engineering design information management system. Future CAD systems must support a wide range of activities — such as definition, manipulation and analyses of complex product information models. These models represent not only conventional data associated with current CAD applications, but also design information characterizing the correlations between the requirements, functions, behaviors and physical form of the product. Such functionality is important for both the individual designer and the design organization, as the need to manage information as a corporate asset is becoming a critical component of business strategy. This paper explores these needs using two design studies. The first study illustrates some major concepts relative to non-routine design activities, while the second study focuses on the routine design activities relative to organization interactions. These studies were used to elicit high level requirements which serve as the basis for the development of prototype software systems. These prototypes are briefly introduced here.     

An integrated agent-based approach for responsive control of manufacturing resources

Due to the dynamic fluctuation of customer demands in the global market, manufacturing enterprises are facing difficulties in rapidly responding to market changes. The aim of this research is to develop a system to integrate dynamic process planning and dynamic production scheduling for the purpose of increasing the responsiveness of adaptive manufacturing systems in accommodating dynamic market changes (rapidly changing demand patterns or product varieties). The concept of Multi-Agent Systems (MAS) has been adopted in this study. All of the tasks related to process planning, optimization and scheduling in this system are carried out by autonomous agents that are capable of interacting and negotiating with each other to bid for jobs and make decisions. On the one hand, this system optimizes the utilization of manufacturing resources and on the other hand, it also provides a platform where the reconfiguration of manufacturing systems can be assessed. This system has been implemented on a Java platform and a case study is provided to elaborate on this system and evaluate its implementation.     

Development of a web-based decision support system for supporting integrated water resources management in Daegu city,South Korea

Demands on fresh water by human beings have been continuously increasing due to population growth, living standard improvement, and economic development. At the same time, many regions are suffering greatly from floods and droughts. Those are the results of ineffective management of water resources due to the associated complexities. In this study, a decision support system (DSS) was developed for supporting integrated water resources management in Daegu city, Republic of Korea. The developed DSS contained four subsystems including database, modelbase, and knowledgebase, as well as general user interface (GUI). It was then connected with the National Water Management Information System (WAMIS). A flow prediction could be conducted through the incorporated HEC-HMS Version 3.0.1. Also, an urban water demand forecasting model was developed using an artificial neural network (ANN) based model. At the same time, a water resources management model based on genetic algorithm (GA) was developed in the DSS, facilitating efficient allocation of water resources among different regions within a city. The result indicated that the developed DSS is very useful to deal with complex water resources management problems and could be further applied to similar cities in South Korea.     

The management of computing resources in schools*

The paper begins with a review of current uses of microcomputers in secondary, primary and special schools and an examination of present and probable administrative uses of the technology in schools. Without entering into pedagogical arguments (and research is needed to provide ammunition for these), the uses which the author considers feasible are indicated, given the resources available, coming down firmly in favour of group rather than individual work in most circumstances. By way of illustration, details are given of some representative applications of computers in the classroom, and a comprehensive picture may be obtained by following up the references and footnotes. The problems of the management of resources are dealt with under three headings: ‘physical security of the equipment’ — safeguards may lead to restricted use; ‘management of the hardware and software’ — the resources required are considerable and whole-school policies are needed under the aegis of senior management; ‘in-service training’ – a continuing programme is needed at a number of levels.     

Human resources management

Human resource management (HRM) demands effective coordination and control over a wide range of activities by management committed to the pursuit of sound human and industrial relations policies. The paper includes a brief comment on the contribution of behavioural and social systems studies, and the practical application of HRM is discussed in broad outline. Finally, a plea is made to the DP manager that whilst carrying the full burden of technological development, he/she should not neglect those other aspects of the management task that contribute to the overall performance of a DP unit.     

Intelligent agents for the management of complexity in multimodal biometrics

Current approaches to personal identity authentication using a single biometric technology are limited, principally because no single biometric is generally considered both sufficiently accurate and user-acceptable for universal application. Multimodal biometrics can provide a more adaptable solution to the security and convenience requirements of many applications. However, such an approach can also lead to additional complexity in the design and management of authentication systems. Additionally, complex hierarchies of security levels and interacting user/provider requirements demand that authentication systems are adaptive and flexible in configuration. In this paper we consider the integration of multimodal biometrics using intelligent agents to address issues of complexity management. The work reported here is part of a major project designated IAMBIC (Intelligent Agents for Multimodal Biometric Identification and Control), aimed at exploring the application of the intelligent agent metaphor to the field of biometric authentication. The paper provides an introduction to a first-level architecture for such a system, and demonstrates how this architecture can provide a framework for the effective control and management of access to data and systems where issues of privacy, confidentiality and trust are of primary concern. Novel approaches to software agent design and agent implementation strategies required for this architecture are also highlighted. The paper further shows how such a structure can define a fundamental paradigm to support the realisation of universal access in situations where data integrity and confidentiality must be robustly and reliably protected .     

An integrated decision system for inventory management

Decision rules for inventory control parameters are combined in a microcomputer based information and decision system. Decision rules implemented in IDSIM cover a wide variety of models for deterministic and stochastic demand cases. The system consists of four modules: The determination of economic order and production quantities and the evaluation of any arbitrary ordering rule in terms of carrying and ordering costs are accomplished in the first module. The second module deals with aggregate level decisions for deterministic demand systems, generates Total Cycle Stock curves, and addresses the problems of group replenishment and group discounts for deterministic systems. The third module calculates the optimum safety stock levels and optimum values of control parameters for order/point quantity as well as periodic review/order-up-to-level parameters in stochastic systems with normal and Laplace distributions. Other sophisticated algorithms, which utilize iterative procedures and yield near optimal solutions, are incorporated in the fourth module for the allocation of total safety stock to minimize either the expected number of stockouts or the total value of shortages.     

System-level integrated power management for handheld systems

We propose a system-level integrated power management scheme for battery-operated handheld systems such as cell phones and PDAs. Rather than dealing separately with each system component, we consider the interactions between CPU, WNIC (wireless network interface card), LCD, and applications, to reduce energy consumption at the system-level. Depending on the type of applications, the proposed scheme takes the interaction between CPU voltage and frequency and either LCD clock frequency or WNIC power modes, selectively, or both of them. The proposed method selects voltage for CPU in the context of LCD clock speed to reduce the system energy consumption. The application type and the power mode of WNIC are also considered to control the CPU voltage and frequency. Experimental results show that our scheme reduces the system energy consumption by as much as 30% compared to the systems of simply combining DVS (dynamic voltage scaling) and DPM (dynamic power management) or those of using no energy saving policy.     

An integrated fuzzy-GA approach for buffer management

This paper deals with a novel buffer management scheme based on evolutionary computing for shared-memory asynchronous transfer mode (ATM) switches. The philosophy behind it is adaptation of the threshold for each logical output queue to the real traffic conditions by means of a system of fuzzy inferences. The optimal fuzzy system is achieved using a systematic methodology, based on genetic algorithms (GAs), which allows the fuzzy system parameters to be derived for each switch size, offering a high degree of scalability to the fuzzy control system. Its performance is comparable to that of the push-out (PO) mechanism, which can be considered ideal from a performance viewpoint, and at any rate much better than that of threshold schemes based on conventional logic. In addition, the fuzzy threshold (FT) scheme is simple and cost-effective when implemented using VLSI technology.     

Empirical analysis of CK metrics for object-oriented design complexity: implications for software defects

To produce high quality object-oriented (OO) applications, a strong emphasis on design aspects, especially during the early phases of software development, is necessary. Design metrics play an important role in helping developers understand design aspects of software and, hence, improve software quality and developer productivity. In this paper, we provide empirical evidence supporting the role of OO design complexity metrics, specifically a subset of the Chidamber and Kemerer (1991, 1994) suite (CK metrics), in determining software defects. Our results, based on industry data from software developed in two popular programming languages used in OO development, indicate that, even after controlling for the size of the software, these metrics are significantly associated with defects. In addition, we find that the effects of these metrics on defects vary across the samples from two programming languages-C++ and Java. We believe that these results have significant implications for designing high-quality software products using the OO approach.     

Implications of complexity and uncertainty for integrated modelling and impact assessment in river basins

The paper focuses on implications of complexity and uncertainty in climate change impact assessment at the river basin and regional scales. The study was performed using the process-based ecohydrological spatially semi distributed model SWIM (Soil and Water Integrated Model). The model integrates hydrological processes, vegetation/crop growth, erosion and nutrient dynamics in river basins. It was developed from the SWAT and MATSALU models for climate and land use change impact assessment. The study area is the German part of the Elbe River basin (about 100,000 km²). It is representative for semi-humid landscapes in Europe, where water availability during the summer season is the limiting factor for plant growth and crop yield. The validation method followed the multi-scale, multi-site and multi-criteria approach and enabled to reproduce (a) water discharge and nutrient load at the river outlet along with (b) local ecohydrological processes like water table dynamics in subbasins, nutrient fluxes and vegetation growth dynamics at multiple scales and sites. The uncertainty of climate impacts was evaluated using comprehensive Monte Carlo simulation experiments.     

Model-driven estimation approach for system reliability using integrated tasks and resources

The increasing complexity of software systems in embedded systems or industrial business domains has led to the importance of reliability analysis for current systems. Reliability analysis has become a crucial part of the system development life cycle, and a new approach is needed to enable an early analysis for reliability estimation, especially for the system under design. However, the existing approach neglects the correlation between system resource and system task for estimating system reliability. This subsequently restricts accuracy of the estimation as well as causing difficulties in identifying critical resources and tasks during the design phase. This paper proposes a model-driven system reliability estimation using a scenario-based approach to estimate system reliability and identify its critical resources and system tasks during the design phase. This model is based on the PerFAM model, which can specifically view timing failures through a system scenario. The proposed approach is validated by the application of a sensitivity analysis into one case study. The case study demonstrates an essential relationship between system reliability, as well as both resources and tasks, which ultimately becomes the integral part for a system reliability estimation assessment.     

一体化网络中基于位置的组密钥管理方案

一体化网络为了支持安全性和移动性,将成员的身份和位置信息进行分离。对于贡献型组密钥管理算法,如果仅仅考虑成员的身份,而不考虑位置,将会导致在物理位置上相隔很远的成员进行消息的交互,使得组密钥的生成时间较长。本文借助主机距离估计技术来探测成员的位置,提出基于位置的贡献型组密钥管理方案L—TGDH来快速的生成组密钥。