• Venture DIGEST
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• s.92
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• pp.36-37
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• 2006

멕시코는 잠재적 시장성과 아메리카 대륙의 교두보로서의 중요성에 비해 우리에게는 그리 잘 알려지지 않은 시장이다. 몇몇 대기업과 섬유·화학 중소기업이 직접투자 형태로 진출해 있을 뿐 중소기업들 대부분은 초기단계에 머물고 있다. 멕시코 시장의 잠재력과 가능성을 소개함으로써 기술력 있는 중소·벤처기업들의 멕시코 진출이 늘어나는 계기가 되었으면 한다.

• Electronics and Telecommunications Trends
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• v.8 no.2
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• pp.102-107
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• 1993

본고는 일본의 전기통신설비중 디지틀계 통신망에 접속되는 가입자용 커넥터 규격(8핀, 15핀, 25핀, 34핀, 37핀 등)에 대한 규제동향을 파악한 것이며, 세부적으로는 각 핀들의 물리적 형태, 전기적 조건의 적용 등이 조사 분석되었다.

• 정보화사회
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• s.123
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• pp.31-37
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• 1998

98년도에 들어서면서 CATV망을 이용한 초고속 인터넷 접속서비스(케이블넷)시장이 국내에서도 본격적으로 열리고 있다. 현재 국내에는 크게 3가지 형태의 CATV망이 구축되고 있다. 중계유선사업자의 자가망과 한국통신의 한통망, 한국전력의 한전망이 그것이다. 따라서 각자 자신의 CATV망을 이용하여 부가서비스 시장을 선전하기 위한 시도가 활발하게 이루어지고 있다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.5A
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• pp.305-315
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• 2003

MC-CDMA(Multicarrier code division multiple access), which is based on a combination of OFDM(orthogonal frequency division multiplexing) and CDMA(code division multiple access), has gained a lot of interests in wireless multimedia communications, as high speed data transmission is required for mobile services. MC-CDMA has many advantages for broadband high speed data transmission in multipath environment because it can offer both advantages of the CDMA and the OFDM. However, A high PAPR(peak to average power ratio) problem, which is a major drawback of OFDM, is also shown in the MC-CDMA. In this paper, we propose a new phase factor optimization scheme to reduce complexity in PTS(partial transmit sequence) to reduce PAPR. We also analyze the performance of the MC-CDMA with various PTS schemes to investigate the relations between PAPR characteristics and effect of nonlinear distortion of a high power amplifier. Our simulation results reveal that the proposed PTS scheme reduces PAPR about 0.2∼0.5 dB even with 25% reduced- complexity compared to the conventional scheme.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.17 no.2
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• pp.99-113
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• 1992

In general, TDMA and FDMA have been used for multiple access communication methods. Recently. However, ALOHA and CSMA protocols came to exist as new schemes for VSAT data networks and LANs, respectively. These schemes are proven to be effective for packet switched communication systems that has bursty traffic but packet collisions. In this paper we analyze capture statistics arising from fading channels in packet radio communication systems in the context of ALOHA protocol. We derive general results of the exact form of capture probabilities and present numerical data for wide range of fading parameters. Since the capture probabilities are found to approach zero when the number of transmitted signals become larger, we are able to determine the achievable channel throughput by a least squares fitting of an exponential-type function to the probabilities.

• Journal of Korean Society of Transportation
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• v.24 no.3 s.89
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• pp.51-61
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• 2006

Interchanges are passages for vehicle and pedestrians and a gateway to nearby facilities, and a place to stay of vehicle and Pedestrians. Interchange traffic must be able to navigate well for safety and convenience. Traffic safety and efficiency are influenced by the interchange. In this study, relative delays of vehicles are compared by changing traffic interchanges. the volume of traffic, the number of lanes, the rate of left turns vehicle on the interchanges of urban arterial roads. The object of this study is to compare Grade crossing interchange, Diamond interchange. Roundabout interchange. SPUI(Single Point Urban Interchange), Echelon interchange). Echelon interchange. By VISSIM Simulation, this study drew the relative delay value of every scenario and compared the delay value of each vehicle considering construction expenses. Through this comparison study, ideal interchange is dependent on the volume of traffic, the number of lanes, and the rate of left turns.

• Journal of the Microelectronics and Packaging Society
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• v.21 no.1
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• pp.25-29
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• 2014

In this study, an optical PCB was proposed which can overcome the limitations of the conventional PCB, and a new structure with pluggable lens was considered for a high-efficient passive alignment. The structure was a lens-added optical waveguide for the improvement of misalignment between the lens and the waveguide in the alignment. Also, as it had a barrier-type structure to prevent the surface damage of the lens by desorption, the high-efficient passive alignment can be realized. The structure was designed by optimizing the simulation and the fabrication process of the pluggable lens structure was conducted using the repetitive photolithography and the thermal reflow. The optical waveguide with the lens-integrated pluggable interconnection was fabricated by the imprint process using the polydimethylsiloxane(PDMS) replica mold. Therefore, we confirmed the possibility of pluggable lens-added optical waveguide structure fabrication for high-efficient passive alignment.

• The Transactions of the Korea Information Processing Society
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• v.4 no.10
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• pp.2521-2532
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• 1997

The next generation internet protocol, IPv6, have been developed by the IETF according to the requirements of enhancement of classic IP protocols to satisfy the lack of Internet address space as well as the support of multimedia applications. This paper presents an implementation of IPv6 protocols on the Windows NT kernel environment. In this work, we developed and also tested the basic functions, required for operating as an IPv6 host, such as IPv6 header processing, IPv6 address handling, control message processing, group membership processing and neighbor discovery functions. The implemented IPv6 protocol driver module is connected to the lower network interface card through NDIS, a standard network interface. And this driver module that operates within kernel, is implemented as it is connected to upper user applications and lower NDIS using dispatch and lower-edge functions. The developed IPv6 protocol driver can provide not only enhanced performance because it is implemented in kernel mode, but also convenience of usage to the application developers because it gives user interface as a dynamic link library.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.8 no.5
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• pp.885-892
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• 2018

A series of revolutionary industrial changes took place from the 18th century of the First Industrial Revolution. The fourth industrial revolution is a new industrial revolution in which intelligence and information unite. Social, cultural, economic and educational systems are expected to emerge within the category of access and experience. In the course of intelligent mechanization, manpower and machinery need to be commandeered. Tools should be left to the machine and humans should look at essential issues. In the 4th Industrial Revolution, the paradigm of education should fundamentally change. Instead of routine technologies based on memorization, one should learn how to access and utilize. It needs to focus on areas of debate, cooperation, communication, sensibility, and artistry that robots and artificial intelligence can not afford. The fourth industrial revolution is the fusion of human beings and technology, the humanities and the technology.

• Journal of Internet Computing and Services
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• v.5 no.3
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• pp.87-98
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• 2004

There are several types of distributed subscribers network using Asymmetric Digital Subscriber Line (ADSL), Very high-bit rate Digital Subscriber Line (VDSL), and Data Over Cable Service Interface Specifications (DOCSIS), The efficient and concentrated network management of those several distributed subscribers networks and resources require the general information model of network, which has abstract and conceptional managed objects independent of type of network and its equipment to manage the integrated subscriber network, This paper presents the general Internet subscribers network modeling framework using RM-ODP (Reference Model Open Distributed Processing) to manage that network In the form of integrated hierarchy, This paper adopts the object-oriented development methodology with UML (Unified Modeling Language) and designs and implements the HFC network of DOCSIS as an example of the subscriber network.