• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.8
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• pp.26-33
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• 2017

Vehicle communication can facilitate efficient coordination among vehicles on the road and enable future vehicular applications such as vehicle safety enhancement, infotainment, or even autonomous driving. In the $3^{rd}$ Generation Partnership Project (3GPP), many studies focus on long term evolution (LTE)-based vehicle communication. Because vehicle speed is high enough to cause severe channel distortion in vehicle-to-vehicle (V2V) environments. We can utilize channel estimation methods to approach a reliable vehicle communication systems. Conventional channel estimation schemes can be categorized as least-squares (LS), decision-directed channel estimation (DDCE), spectral temporal averaging (STA), and smoothing methods. In this study, we propose a smart channel estimation scheme in LTE-based V2V environments. The channel estimation scheme, based on an LTE uplink system, uses a demodulation reference signal (DMRS) as the pilot symbol. Unlike conventional channel estimation schemes, we propose an adaptive smoothing channel estimation scheme (ASCE) using quadratic smoothing (QS) of the pilot symbols, which estimates a channel with greater accuracy and adaptively estimates channels in data symbols. In simulation results, the proposed ASCE scheme shows improved overall performance in terms of the normalized mean square error (NMSE) and bit error rate (BER) relative to conventional schemes.

• Korean Journal of Construction Engineering and Management
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• v.14 no.6
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• pp.90-101
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• 2013

A typical construction project involves participation of various parties including clients, contractors, architects, and engineers for its successful completion, and yet has intrinsic differences of interests among the participants during the project execution period. A construction management (CM) services's role is then to resolve these differences of interests among the participants during the project execution, and lead the projects to its successful completion while representing the clients' demands and interests. The use of building information modeling (BIM) is increasing recently among construction projects, and those CM service companies are experiencing difficulties applying BIM. This is because the use of BIM in construction projects suggests a quite new set of operational paradigm. The purpose of this paper is then to review the recent cases of projects which used BIM; to analyze the these projects' processes; to reengineer the design phase process based on the lessons learned from recent BIM application; and to suggest a modified design phase process model that could improve the use of BIM and related coordination operations.

• International Commerce and Information Review
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• v.14 no.1
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• pp.315-344
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• 2012

Each country has set low-carbon green growth to a new growth drive for the future while making various efforts. Accordingly, our country also set green growth to our policy task in top priority throughout our country while initiating various policies. Our country has focused on initiating a few policies in green growth. Our country has focused on the development of green industries to secure our national competitiveness while generating added values in green growth. It is necessary to have studies in initiating policies in balance when we consider that green growth should be initiated through the shift over the whole lifestyle. On the other hand, policies led and driven by the central government have been emphasized. Although the planning and establishment of policies might be said to fall under the central government's main areas, green growth policies can be realized regionally in the end. Considering these circumstances, the coordination in a proper way between the central government and each municipality can also be seen as major characteristics only in our country, which can be hardly seen in other countries. This study aims at developing the initiative strategies in our country's green logistics while analyzing the characteristics of green growth and situations of green logistics initiative, studying the government's policies to support green logistics, reviewing the government's policies for supports, and suggesting alternatives for them.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.7
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• pp.741-753
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• 2008

This paper explores the throughput performance of CSMA/CA-based DCF protocol over both ideal channels and fading channels with payload size at the MAC layer in the 802.11a wireless LAN. In the ideal channel, there are no errors and at the transmission cycle there is one and only one active station which always has a packet to send and other stations can only accept packets and provide acknowledgements. In the fading channel, bit errors appear in the channel randomly and the number of stations is assumed to be fixed. And each station always has packets for transmission. In other words, we operate in saturation conditions. Up to now conventional research work about DCF throughput analysis of IEEE 802.11 a wireless LAN has been done over the ideal channel, but this paper is done over the Rayleigh/Ricean fading channel. So, the ratio of received average energy per bit-to-noise power spectral density $E_b/N_o$ is set to 25 dB and the ratio of direct-to-diffuse signal power in each sub-channel $\xi$ is set to 6 for combined Rayleigh/Ricean fading channel. In conclusion, it is shown that the saturation throughput is always less than the maximum throughput at all the payload size and the higher the transmission rate be, the higher the decreasing rate of saturation throughput compared to the maximum throughput be.

• Journal of Korea Society of Industrial Information Systems
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• v.13 no.4
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• pp.115-131
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• 2008

As the innovation of computer and communication technology, IT has played a role of increasing the business efficiency and offering new business opportunities. Many organizations have tried to launch IT projects, and the investment scale has been getting bigger. However, a lot of IT projects have been failed because of the difficulties of project management. Therefore, the purpose of this study is to know how the roles of project governance affect the project performance and what role of the project governance will be affected to solve the problems which might be taken place while developing the project. As the results of this study, the roles of project governance - linking, coordination, control, strategic direction, support, societal embedding, highly affect the project performance. To solve the problems which might be occurred while implementing the project, the control and the societal embedding roles playa crucial role compared to the other roles of the project governance. In other words, the roles of project governance should be utilized for the success of IT project, and the control and the societal embedding of the project governance should be modified and complemented to solve the problems which might be occurred while developing the project.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6277-6283
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• 2012

Background: Northern Iran counts as one of the highest prevalence regions for esophageal cancer (EC) worldwide. This study was designed to assess the epidemiologic aspects of EC in north central and northwest Iran over a 10 year period. Materials and Methods: The Guilan cancer registry study (GCRS) is a population-based cancer registry study featuring retrospective (1996-2003) and prospective (2004-2005) phases. A detailed questionnaire based on WHO standards for cancer registratration was applied to gather the required information. Two trained physicians coded information using ICD-O-3 in close coordination with an expert pathologist. Results: A total of 19,936 cases of malignancy (mean age $55.4{\pm}18.0$ years, range: 1-98 years) were registered, including 1,147 cases (670 males, 447 female; mean age: $64.0{\pm}11.5$ years) of EC. In 1996 the male/female ratio among patients with EC was 1.25 which increased to 1.53 in 2005. The lower third of the esophagus still remained the most common site of tumors. The average age-standardized rate (ASR) was 6.9 and 4.1 per $10^5$ men and women, respectively. In 1996, the ASRs were 7.2 and 5.2 per $10^5$ men and women which decreased to 6.9 and 4.1 per $10^5$ in 2004-2005. Squamous cell carcinoma (SCC) was the most prevalent histological subtype of EC accounting over 80% of cases. Conclusions: However the prevalence of adenocarcinoma (ADC) showed an increase to 18.4%. Guilan province may be considered a relatively low incidence region for EC.

• Proceedings of the Korean Information Science Society Conference
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• 1998.10c
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• pp.279-281
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• 1998

CSCW는 지리적으로 분산된 작업자 간의 효율적인 의사소통을 위해 화상회의, 채팅(chatting), 화이트 보드(white board), 그리고 텔리포인팅(telepointing)과 같은 기능들을 제공한다. 이 중 텔리포인팅은 지역 시스템(local system)의 공유 윈도우(shard window)에서 텔리포인터(telepointer)를 통해 발생한 이벤트를 원격지 시스템(remote System)의 공유 윈도우에서 나타낼 수 있도록 하는 기능을 제공함으로써 작업자 간의 보다 효율적인 의사소통을 가능하게 한다. 이러한 의사소통 기능으로써의 텔리포인팅은 원격진료, 공동작업 플랫폼에 관한 연구에서 응용된 바 있으나 공동저작을 위한 텔리포인팅 기능에 관한 연구 및 이를 공동저작 관리 시스템 구조에 관한 연구가 미흡하다. 공동제작에서의 텔리포인팅은 저작자 간의 의사소통을 위한 기능 뿐만 아니라 동기적 공동저작과 동기적 프리젠테이션을 위한 기능으로써 응용될 수 있어야 한다. 이를 위해 공동저작 관리 시스템은 저작자 그룹인 세션(session) 단위로 텔리포인터에 대한 권한 관리와 텔리포인팅을 통한 공유객체 엑세스(access) 기능을 제공해야 한다. 또한 텔리포인팅 구조(telepointing architecture)는 텔리포인팅 이벤트의 멀티캐스팅(multicasting) 및 동기화(synchronization)를 위해 중앙에서 이벤트를 조정하는 텔리포인팅 조정 에이전트 (telepointing coordination agent)와 각 저작자의 지역 시스템에 존재하며 공유 윈도우로부터 지역 이벤트(local event)를 인식하고 텔리포인팅 이벤트를 공유 윈도우에 알리는 텔리포인팅 지역 에이전트(telepointing local agent)로 구성되어야 한다. 본 논문은 공동저작을 위한 텔리포인팅의 기능들과 이를 위한 공동저작 관리 시스템 구조를 설명하고 텔리포인팅 구조를 제시한다.cid 함량이 가장 많이 용출된 분획은 sodium hydroxide 부분으로서 hemicellulose구조가 polyuronic acid의 형태인 것으로 사료된다. 추출획분의 구성단당은 여러 곡물연구의 보고와 유사하게 glucose, arabinose, xylose 함량이 대체로 높게 나타났다. 점미가 수가용성분에서 goucose대비 용출함량이 고르게 나타나는 경향을 보였고 흑미는 알칼리가용분에서 glucose가 상당량(0.68%) 포함되고 있음을 보여주었고 arabinose(0.68%), xylose(0.05%)도 다른 종류에 비해서 다량 함유한 것으로 나타났다. 흑미는 총식이섬유 함량이 높고 pectic substances, hemicellulose, uronic acid 함량이 높아서 콜레스테롤 저하 등의 효과가 기대되며 고섬유식품으로서 조리 특성 연구가 필요한 것으로 사료된다.리하였다. 얻어진 소견(所見)은 다음과 같았다. 1. 모년령(母年齡), 임신회수(姙娠回數), 임신기간(姙娠其間), 출산시체중등(出産時體重等)의 제요인(諸要因)은 주산기사망(周産基死亡)에 대(對)하여 통계적(統計的)으로 유의(有意)한 영향을 미치고 있어 $25{\sim}29$세(歲)의 연령군에서, 2번째 임신과 2번째의 출산에서 그리고 만삭의 임신 기간에, 출산시체중(出産時體重) $3.50{\sim}3.99kg$사이의 아이에서 그 주산기사망률(周産基死亡率)이 각각 가장 낮았다. 2. 사산(死産)과 초생아사망(初生兒死亡)을 구분(區分)하여 고려해 볼때 사산(死産)은 모성(母性)의 임신력(姙娠歷)과 매우 밀접한 관련이 있는 것으로 사료(思料)되었고 초생아사망(初生兒死亡)은 미숙아(未熟兒)와 이에 관련된 병발이 거의 결정적(決定的) 원인(原因)이 된다고 사료(思料)되었다. 3. 주산기사망률(周産基死亡率)을 감소시키는 관점(觀點)에서의 모자보건사업(母子保健事業)은 미숙아방지책(未熟兒防止策

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37B no.12
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• pp.1091-1101
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• 2012

Device-to-device (D2D) communication is expected to offer local area services with low transmit power and short link distance, even not via any infrastructures. These advantages will lead to the deployment of D2D systems in a massive scale, where the order of magnitude of D2D user density is higher than that of cellular user density. Network-assisted D2D systems, where D2D resources are managed by cellular networks, are unable to support the large number of D2D devices, due to the signaling overhead for control signals. In this case, no coordination can be an answer. This paper considers uncoordinated D2D systems, which is implemented with a number of D2D devices in a large scale. By analyzing the transmission capacity of D2D systems, we found a feasibility condition under which the uncoordinated D2D communications possibly coexist within cellular networks, sharing the uplink spectrum. In addition, we provide guidelines for the operational points of massive D2D communications, giving some knowledge about proper transmit power level and link distance of uncoordinated D2D.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.4
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• pp.552-557
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• 2020

The Radar Cross Section (RCS) is a virtual region indicating the strength of a wavelength at which a radar signal is reflected and received. As the ship's RCS represents its own stealth performance and survivability, efforts have been made in various areas from design to construction to reduce the RCS. The RCS can be predicted using design drawings and CAD models, but it is necessary to measure the RCS at sea since sea clutter and multipath reflections occur in the sea environment. However, such RCS predictions and measured values provide only a simple relative magnitude to the user, and there has not been much research on this topic. In this paper, a missile countermeasure technique was studied using 3D RCS measurement data in an operating environment. The elevation and azimuth angle of the ship viewed from the missile were estimated using the location information of the missile, and the RCS value was inverted by mapping it to previously measured 3D RCS measurement data. In addition, by using the movement information of the missile, the RCS observed by the missile could be predicted in advance, and this method can be used to propose a response plan based on the maneuvering and chaff system.

• Korean Security Journal
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• no.54
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• pp.101-125
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• 2018

In the police, crime intelligence is the basis of decision making for police's original activities in response to crime. Police decision making is done in various ways such as investigation and prevention of individual cases, allocation of resources, organization prioritization, etc. The purpose of this study was to investigate the activities of the UK policing in analyzing crime intelligence and to reflect them in the policing and to draw implications for the comparison with the Korean police. The UK operates a central police agency based on the local police system, and establishes a National Intelligence Model (NIM) system that operates crime intelligence throughout the country. In order to respond to crimes and risks through coordination and cooperation, rather than by centralized police activities, the intelligence department of the police agencies should not only prevent and suppress crime through the analysis of integrated crime information, but also make police decision-making. In contrast, the Korea police operate crime intelligence, such as statistics, case intelligence, and there is no integrated way to use it. In addition, there are few cases in which the organizational decision - making based on crime intelligence is utilized efficiently and systematically. For development, it is necessary to construct an integrated management system and analysis organization for crime intellgence. Criminal Intelligence Analysis Organizations should seek to reorganize the role of the current intelligence department or to operate a separate analysis system through the information system while maintaining the current role of each department.