• 한국산업정보학회:학술대회논문집
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• 한국산업정보학회 2006년도 춘계 국제학술대회 논문집
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• pp.229-234
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• 2006

E-commerce and business information systems are being introduced in most of enterprises with the development of internet recently. Meanwhile the introduction of enterprise portal concepts and the enterprise informatization provide a necessary premise for insuring a competitive power. Therefore, it became necessary to research on the project of reusing the data of e-commerce. In this paper, we make a domestic maker the subject and implement a XML based electronic catalog(e-catalog) system for electronic commerce(e-commerce) based on web. The implemented XML based e-catalog system can reduce time and expenses needed for making, keeping and distribution in paper catalog systems. It also can correct the data reuse problems in the e-catalog systems implemented by HTML. Exchanging and reusing data used in e-commerce is essential to the integration between business information systems and points to the enterprise portal.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2000년도 학술발표회 발표논문집
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• pp.458-465
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• 2000

Although Fly ash possess viable engineering properties, an overwhelming majority of the fly ash from coal combustion is still placed in storage or disposal sites. Similarly, sludges generated from various water treatment operations are predominantly subject to the fate of land disposal. To prepare sludges for land disposal typically requires time consuming dewatering schemes, which can become extremely difficult to execute dependent upon the composition of the sludge and its affinity for water. This test was undertaken to reuse of fly ash and sludge with mix. In this paper includes of geotechnical properties of fly ash and fly ash-sludge mixture and results of compaction test, unconfined test, falling head test and CBR test and it was analyzed the effect on mixing fly ash with sludge.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2004년도 가을 학술발표논문집 Vol.31 No.2 (3)
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• pp.226-228
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• 2004

IEEE 802.15.3 High-Rate WPAN(Wireless Personal Area Network)는 l0m내외의 무선 환경에서 실시간 비디오, 고품질 오디오 및 대용량 파일 전송을 가능케 하는 기술이다 하나의 네트워크를 piconet 단위로 구성하고 하나의 Piconet에는 PNC(piconet coordinator)가 TOMA(Time Division Multiple Access) 방식으로 DEV(device)들에게 채널타임을 할당한다. 본 논문에서는 IEEE 802.15.3 High-Rate WPAN 환경에서 하나의 piconet 에 존재하는 각각 통신을 하려는 DEV 들이 서로의 신호에 간섭을 받지 않을 만큼 떨어져 있다면 한 개의 채널타임을 각각의 DEV 들에게 동시에 할당하여 여러 DEV들이 동시에 통신을 하는 공간 재활용방식을 통해 네트워크의 성능을 향상하는 방법을 제안하고 MAC의 공간재활용방식을 통한 네트워크의 성능향상 방법을 연구한다.

• Journal of Communications and Networks
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• 제11권4호
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• pp.406-415
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• 2009

In this work, we consider performance modeling of a wireless sensor network with a time division multiple access (TDMA) media access protocol with slot reuse. It is assumed that all the nodes are peers of each other and they have two modes of operation, active and sleep modes. We model the sensor network as a Jackson network with unreliable nodes with on and off states. Active and sleep modes of sensor nodes are modeled with on and off states of unreliable nodes. We determine the joint distribution of the sensor node queue lengths in the network. From this result, we derive the probability distribution of the number of active nodes and blocking probability of node activation. Then, we present the mean packet delay, average sleep period of a node and the network throughput. We present numerical results as well as simulation results to verify the analysis. Finally, we discuss how the derived results may be used in the design of sensor networks.

• ETRI Journal
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• 제33권4호
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• pp.633-636
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• 2011

In this letter, we propose an overlaid hybrid division duplex (HDD) concept for cellular systems which divides a cell into inner and outer regions and utilizes the merits of both time division duplex (TDD) and frequency division duplex (FDD). The proposed system can take advantage of both TDD and FDD without handover between two duplex schemes. Moreover, it is shown that the proposed HDD system outperforms the conventional TDD or FDD system with mobile relay stations when the synchronization issue is considered in orthogonal frequency division multiple access systems. Thus, the proposed overlaid HDD can be considered as a new framework for future cellular systems.

• 한국시뮬레이션학회논문지
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• 제14권3호
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• pp.79-90
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• 2005

There are plenty of optimization models for the signal-system of a single intersection and area traffic. Some of those models are adopted for the real traffic signal control system. The simulators for a single crossroad have been developed, so that we could evaluate optimization models and traffic control systems. However, the simulators for the area traffic are still being developed. Therefore, there are many limitations in the analysis and evaluation for area traffic control system. The area traffic is consisted of several intersections which are very complicated and many traffic strategies are adopted for the control system. This paper features an effective area traffic control system based on the High Lever Architecture(HLA). In this paper, we discuss the design of HLA-based area traffic control simulation. We describe technical motivations for the HLA, the key elements of the architecture and how they are minimum and essential to the goal of reuse and interoperability. A distributed simulation with HLA/RTI provides stable and satisfactory experimental results. Moreover, the prototype traffic control system provides reliable accomplishment compared to the NETSIM and TRANSYT-7F models.

• 전자공학회논문지C
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• 제34C권6호
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• pp.22-27
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• 1997

This paper propose a novel VLSI architecture for a multiplierless FIR filter chip providing variable-length taps. To change the number of taps, we propose two special features called a data-reuse structure and a recurrent-coefficient scheme. These features consist of several MUXs and registers and reduce the number of gates over 20% compared with existing chips using an address generation unit and a modulo unit. Since multipliers occupy large VLSI area, a multiplierless filter chip meeting real-time requirement can save large area. We propose a modified bit-serial multiplication algorithm to compute two partial products in parallel, and thus, the proposed filter is twice faster and has smaller hardware than previous multiplierless filters. We developed VHDL models and performed logic synthesis using the 0.8.mu.m SOG (sea-of-gate) cell library. The chip has only 9,507 gates, was fabricated, and is running at 77MHz.

• Journal of Mechanical Science and Technology
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• 제20권10호
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• pp.1527-1533
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• 2006

Workflow systems have benefited the enterprise and customer in many aspects. But with the increasing complexity of the system, workflow design becomes a complicated and time-consuming process. In this paper, we model the system based on the Hierarchical Colored Petri Nets (HCPN) to avoid the complexity of the system, and the super nets of the model are abstracted as independent components to increase the flexibility, acceptability and maintainability of the system. Another important characteristic of this model is its convenience for reuse and workflow mining. The development process of the overhead traveling crane was given to demonstrate the proposed method.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2006년도 춘계종합학술대회
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• pp.549-554
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• 2006

The objective of this paper is to propose a system by means of which the utilization of radio frequency spectrum may be improved from the state of extreme inefficiency at the present time in Kazakhstan to a state of efficiency and equilibrium in the future. The main solutions to efficiently use radio frequency spectrum in Kazakhstan will be described in this paper. There are 'Spectrum Utilization, Spectrum Sharing and Reuse the Spectrum' in which the radio frequency can be propagated in wide range using smalt amount of spectrum, or broadcast several channels via one spectrum sharing. In order to embed these systems in practice it will be better to make modifications consider Government policy and geographical and social requirements.

• Journal of information and communication convergence engineering
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• 제2권2호
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• pp.106-109
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• 2004

This study designs a load balancer via direct routing that share a virtual service on a single IP address in the Linux system and suggests an efficient load balancing method to improve transmission speed in the web server cluster environment. It will increase performance and scalability with fast packet transfer and removing bottleneck problem by using TCP Splicing and Content-Aware Distributor method. This method is expected to be the noticeable technology that provides an important interface, which make application services for e-commerce effectively be applied to high-speed network infrastructure. At this time, it is required to study further on the optimum balancing method in the web server cluster environment so as to apply the hybrid (optimum load balancing method by software and hardware) method and improve the reuse of security cession based on high-speed TCP connections.