• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.9
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• pp.912-918
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• 2003

In this paper, we designed and implemented the dual band monopole antenna for cellular CDMA(Code Division Multiple Access) and IMT-2000(International Mobile Telecommunication 2000) repeater. The antenna was designed by using 3D simulations program, HFSS(High Frequency Structure Simulator). Electrical characteristics were measured by using HP 8720C network analyzer and measured maximum S$\_$11/ was -10.9 dB for all frequency bands of interests in Cellular CDMA and IMT-2000. Simulation results for antenna gain at 859 MHz and 2027.5 MHz were 2.38 dBi and 4.02 dBi respectively with omni directional radiation pattern. The size of implemented antenna is compact and the antenna can be produced in low cost enough for commercialization.

• Journal of Communications and Networks
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• v.2 no.1
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• pp.5-17
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• 2000

cdma2000 offers several enhancement as compared to TIA/EIA-95, although it remains fully compatible with TIA/EIA-95 systems and allows for a smooth migration from one to the other-Major new capability include:1)connectivity to GSM-MAP in addition to IP and IS-41 networks; 2) new layering with new LAC and MAC architectures for improved service multiplexing and QoS management and efficient use of radio resource ;3) new bands and band widths of operation in support of various operator need and constraints, as well as desire for a smooth and progressive migration to cdma 2000; and 4) flexible channel structure in support of multiple services with various QoS and variable transmission rates at up to 1 Mbps per channel and 2 Mbps per user. Given the phenomenal success of wireless services and desire for higher rate wireless services. improved spectrum efficiency was a major design goal in the elaboration of cdma2000. Major capacity enhancing features include; 1) turbo coding for data transmission: 2)fast forward link power control :3) forward link transmit diversity; 4) support of directive antenna transmission techniques; 5) coherent reverse link structure; and 6) enhanced access channel operation. As users increasingly rely on their cell phone at work and at home for voice and data exchange, the stand-by time and operation-time are essential parameters that can influence customer's satisfaction and service utilization. Another major goal of cdma2000 was therefore to enable manufacturers to further optimize power utilization in the terminal. Major battery life enhancing features include; 1) improved reverse link performance (i.e., reduced transmit power per information bit; 2) new common channel structure and operation ;3) quick paging channel operation; 4) reverse link gated transmission ; and 5) new MAC stated for efficient and ubiquitous idle time idle time operation. this article provides additional details on those enhancements. The intent is not to duplicate the detailed cdma2000 radio access network specification, but rather to provide some background on the new features of cdma2000 and on the qualitative improvements as compared to the TIA/EIA-95 based systems. The article is focused on the physical layer structure and associated procedures. It therefore does not cover the MAC, LAC, radio resource management [1], or any other signaling protocols in any detail. We assume some familiarity with the basic CDMA concepts used in TIA/EIA-95.

• Journal of KIISE:Information Networking
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• v.29 no.1
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• pp.15-23
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• 2002

We present a new MDA-based Mobile-IPv6 multicast routing algorithm for wirelese service operators to offer Mobile-IP over IMT-2000 service under IMT-2000 network by taking advantage of the existing infrastructure for IMT-2000 multimedia application services. The extended IMT-2000 system architectures use an PDSNs (i.e. IWFs), and the home network (i.e. Internet) backbone and intermediate network are composed of ATM entities. A key feature of the new protocol is the use of MDA(Multicast Delivery Agent) to reduce delivery path length of the multicast datagram. We show that proposed protocol is efficient in terms of various performance measures such as multicast traffic load, multicast related handoff, and average routing length when we implement it using the Mobile-IPv6. Particularly, the number of tunneling and average routing length of datagram are reduced relatively, the multicast traffic load is also decreased.

• Journal of Advanced Marine Engineering and Technology
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• v.34 no.1
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• pp.125-132
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• 2010

IEC61162-3 known as NMEA2000 protocol is approved as a standard network of SOLAS ship by ISO and used for the instrument network which exchanges data in real-time. For easy the development of ship network equipments, this study is focused on the development of SoC which can convert to NMEA2000 protocol from various kind of protocols such as TCP/IP, NMEA0183, RS422 and others using FPGA and u-Blaze. In this paper, we composed NMEA2000 protocol stack on FPGA and verified NMEA2000 network communication of FPGA system by connecting with commercialized devices through PC Hyper-terminal and network monitoring program.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.28 no.2
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• pp.60-68
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• 2005

ISO 9000 quality standards families were established in 1987 and have been started to implement Korean industry since early 1990s. ISO 9000 standards families of 1987 were revised in 1994 and 2000, respectively, by request of world wide certification bodies and industry quality experts. This article reviews the necessity of ISO 9001 :2000 revision, quality management principles behind it, and benefits that ISO 9001: 2000 could bring. We summarize responses of foreign industry that ISO 9001: 2000 has been implemented. Survey questionnaire for 23 requirements of ISO 9001: 2000 from manufacturing companies of Busan and Kyungnam provinces are collected. Research hypotheses that there is any difference in quality management system practical application due to company size and implementation motivation are tested using SPSS. Finally, recommendations are provided for operating successful quality management system.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.6
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• pp.965-971
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• 2001

In this paper, the triangular u-slot patch antenna for the PCS & IMT-2000 dual band are studied. The frequency bandwidth of a triangular u-slot patch antenna can be increased by L-strip fed structure. The impedance bandwidth(VSWR$\leq$2) of the fabricated single element is 590 MHz(30.18 %). Using the frequency bandwidth of PCS & IMT-2000, we confirm VSWR below 1.65, which is a good characteristic. Thus the wideband characteristic of the L-strip fed structure is confirmed experimentally.

• Journal of Korean Society for Quality Management
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• v.32 no.4
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• pp.64-77
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• 2004

This paper first was focused on investigating the relative effect of each ISO 9001: 2000 certification factors on service quality and customer satisfaction in service industry. The empirical tests was conducted in service industry. The results are as follows. First, it shows that ISO 9001:2000 certification factors except requirements for quality management have a positive effect on service quality significantly. Second, it also indicates that service quality precedes customer satisfaction like other researches reported. Finally, different effects of ISO 9001:2000 certification factors on service quality are observed in the various industries.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.04a
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• pp.530-533
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• 2014

ISO6954:2000 (Mechanical vibration - Guidelines for the measurement, reporting and evaluation of vibration with regard to habitability on passenger and merchant ships) has taken effect as the governing body for vibration regarding habitability due to ship vibration. However, ISO6954:2000, when compared ISO6954:1984 (the first draft of ISO6954), needs to clear some deficiencies concerning convenience and reliability during field applications. In this paper, ISO6954: 1984 and 2000 are proposed on their revisions in the future.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2000.04a
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• pp.687-690
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• 2000

본 논문은 IMT-2000 시스템 MAC 계층에서의 채널할당 운용에 관한 것이다. 기존의 2 세대 무선이동통신인 셀룰라나 PCS 에서는 주로 음성이 주요한 트래픽이었기 때문에 채널 할당에 관한 운용전략이 간단했다. 그러나 무선구간 데이터 트래픽의 급속한 증가는 IMT-2000 시스템의 등장을 가져왔고 이 시스템은 음성과 함께 데이터를 전송하기 때문에 2 세대보다 채널할당이 복잡할 수 밖에 없다. 데이터 트래적 중 web 트래픽이 주요한 부분이 될 것은 자명하다. 그래서 본 논문에서는 대상이 되는 트래픽을 web 트래픽으로 한정하고, web 트래픽을 크게 2 개의 class로 구분했다 : streaming & non-streaming 그리고 다시 각각의 class를 2개, 3개의 subclass(type)로 나눴다. 이 구분과 함에 IMT-2000 시스템의 멀티미디어 트래픽 모델링을 사용하여 시뮬레이션을 행했다. 시뮬레이션은 전용채널, 공용채널의 수, type 별 확률을 변화시키면서 여러 가지 상황을 고려해봤다.

• Proceedings of the Korea Technology Innovation Society Conference
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• 1998.05a
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• pp.22-22
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• 1998

This paper reviews the benefits of users participation in IMT-2000 standardization by the creation of users coalitions, focusing in particular on phased standards strategy necessary for the evolutionary approach from second generation to third generation systems. It first presents in detail the current status of IMT-2000 standardization progress occurring at each regional standard body including TIA of US, ETSI of Europe, TTA of Korea and ARIB of Japan. With this clear understanding of standardization situations worldwide, we may be able to come up with our standards strategies related to IPR issues and efficient standard-setting mechanism between manufacturers and service providers. In addition, this paper addresses the necessity for phased licensing of IMT-2000 service in order to avoid the high cost of new infrastructures and ensure an acceptable financial investment returns for existing cellular and PCS service providers. An author hopes that this paper can provide the adequate standardization directions of IMT-2000 to satisfy the varying regional and global market requirements.