고속 고신뢰의 UWB 신호 동기획득을 위한 향상된 두 단계 탐색 기법

김재운,양석철,신요안,Kim, Jae-Woon,Yang, Suck-Chel,Shin, Yo-An 한국통신학회 2005 韓國通信學會論文誌 Vol.30 No.12C

본 논문에서는 다중경로 채널 환경의 초광대역 (Ultra Wide Band; UWB) 시스템에서 고속 고신뢰의 동기획득을 위한 향상된 두 단계 신호 탐색 기법인 TSS-LS(Two-Step Search scheme with the Linear search based Second step) 를 제안한다. 제안된 TSS-LS는 기존에 본 저자들이 제안하였던 TSS-BS (Two-Step Search scheme with the Bit reversal search based Second step)와 견줄만한 매우 빠른 동기획득 성능을 달성할 수 있도록 Single-Dwell 연속 동기탐색 기법에 기초하고 있으며 두 개의 다른 임계값과 탐색창을 적용한다. 반면, 제안된 TSS-LS는 UWB 시스템에서 통기획득의 고신뢰성을 보장하기 위해 두번째 단계에서 Bit Reversal 탐색 알고리즘을 사용하는 TSS-BS와는 달리 Linear 탐색 알고리즘을 적용하게 된다. IEEE 802.15.3a의 UWB 다중경로 채별 환경에서의 모의실험 결과, 일반적인 탐색 기법보다 본 논문에서 제안된 두 단계 탐색 기법의 정규화된 평균 동기획득 소요 시간이 큰 폭으로 향상됨을 확인할 수 있었다. 특히, 신호 동기획득 과정과 연동된 비트오율 성능 평가에서 제안된 TSS-LS 기법의 경우 높은 신호대 잡음비에 대해 이상적인 성능에 필적하는 매우 우수한 성능을 보임을 확인할 수 있었다. In this paper, we propose an enhanced two-step search scheme for rapid and reliable signal acquisition in UWB systems under multipath channels. The proposed TSS-LS (Two-Step Search scheme with the Linear search based Second step) achieves rapid acquisition performance comparable to the conventional TSS-BS (Two-Step Search scheme with the Bit reversal search based Second step) already proposed by the authors, based on the single-dwell search with two-step thresholds and search windows. However, unlike the TSS-BS which employs the bit reversal search in the second step, the proposed TSS-LS utilizes the linear search in the second step to improve the reliability of signal acquisition. Simulation results with multipath channel models by IEEE 802.15.3a show that the two-step search schemes for the UWB signal acquisition can achieve sig nificant reduction of the required mean acquisition time as compared to general search schemes. In addition, we observe that the proposed TSS-LS achieves quite good bit error rate performance for large signal-to-noise ratios, which is favorably comparable to the case of ideal perfect timing.

RF-PECVD 법으로 제조된 비정질 BON박막의 산화

김재운,부진효,이동복,Kim J. W.,Boo J.-H.,Lee D. B. 한국재료학회 2004 한국재료학회지 Vol.14 No.10

The BON thin films were grown on the Si substrate by the RF-PECVD method. When stored at the room temperature, the phase separation or transition of BON thin films occurred on the surface, due to the hydrophilic property of BON. The oxidation of BON thin films occurred mainly by the evaporation of B, O and N. The oxidized BON thin films consisted of an amorphous phase and a bit of the polycrystalline phase.

Mo, Nb첨가가 TiAl합금의 산화에 미치는 영향

김재운,이동복,Kim Jae-Woon,Lee Dong-Bok 한국재료학회 2004 한국재료학회지 Vol.14 No.9

Alloys of $Ti46\%Al-2\%Mo-2\%Nb$ were oxidized between 800 and $1000^{\circ}C$ in air, and their oxidation characteristics were studied. The alloys displayed good oxidation resistance due mainly to the beneficial effects of Mo and Nb. The oxide scales formed consisted primarily of an outer $TiO_2$ layer, an intermediate $Al_{2}O_3-rich$ layer, and an inner mixed layer of ($TiO_{2}+Al_{2}O_3$). Molybdenum and niobium dissolved in the scale effectively improved oxidation resistance. They were mainly distributed in the inner mixed layer of ($TiO_{2}+Al_{2}O_3$).

열기계적 처리한 Ti-45.4%Al-4.8%Nb 합금의 고온산화

김재운,이동복,Kim Jae-Woon,Lee Dong-Bok 한국재료학회 2004 한국재료학회지 Vol.14 No.7

The thermomechanically treated $Ti-45.4\%Al-4.8\%Nb(at\%)$ alloy was oxidized between 800 and $1000^{\circ}C$ in air, and the oxidation characteristics were studied. The dissolution of Nb in the oxide scale was observed from the TEM study. The Pt marker test revealed that the oxidation process was controlled by the outward diffusion of Ti ions and the inward diffusion of oxygen ions. During oxidation, the evaporation of Nb-oxides was found to occur to a small amount. Niobium tended to pile-up at the lower part of the oxide scale, which consisted primarily of an outer $TiO_2$ layer, and an intermediate $Al_{2}O_{3}-rich$ layer, and an inner mixed layer of ($TiO_{2}+Al_{2}O_{3}$).

비동기식 초광대역 시스템을 위한 고속 신호 동기획득 기법

김재운,양석철,최성수,신요안,Kim Jae-Woon,Yang Suck-Chel,Choi Sung-Soo,Shin Yo-An 한국통신학회 2006 韓國通信學會論文誌 Vol.31 No.4c

이 논문에서는 다중경로 채널 환경에서 비동기식(Noncoherent) 초광대역(Ultra Wide Band) 무선통신 시스템의 고속 고신뢰 신호 동기획득을 위해, 저자들이 동기식(Coherent) 초광대역 시스템을 위해 제안하였던 TSS-LS (Two-Step Search scheme with Linear search based Second step). 기법을 비동기식 초광대역 시스템에 확장 적용하는 방안을 제안한다. 간단한 에너지 윈도우 뱅크를 사용하는 제안된 비동기식 TSS-LS 기법은 고속의 동기획득을 위해 두 단계의 서로 다른 문턱값과 탐색창을 적용하게 된다. 더욱이 다중경로 채널의 실효 지연 확산 범위에서의 시작 지점을 정확히 찾고 비동기식 초광대역 변복조와 연동했을 때 신뢰성 있는 비트오율(Bit Error Rate) 성능을 얻기 위해 두 번째 단계에서 선형 알고리즘을 적용한다. IEEE 802.15.3a의 다중경로 채널 모형을 이용한 모의실험 결과, 일반적인 탐색 기법보다 제안된 기법의 평균 동기획득 소요 시간이 큰 폭으로 단축됨을 확인할 수 있었다. 또한, 신호 동기획득 과정과 연동된 비트오율 성능 평가에서 신호대잡음비가 높을 때 이상적인 동기획득의 경우에 필적하는 매우 우수한 성능을 보임을 확인할 수 있었다. In this Paper, we propose to extend the TSS-LS(Two-Step Search scheme with Linear search based Second step) scheme which was already proposed by the authors for coherent UWB(Ultra Wide Band) systems, to rapid and reliable acquisition of noncoherent UWB systems in multipath channels. The proposed noncoherent TSS-LS employing simple energy window banks utilizes two different thresholds and search windows to achieve fast acquisition. Furthermore, the linear search is adopted for the second step in the proposed scheme to correctly find the starting point in the range of effective delay spread of the multipath channels, and to obtain reliable BER(Bit Error Rate) performance of the noncoherent UWB systems. Simulation results with multipath channel models by IEEE 802.15.3a show that the proposed two-step search scheme can achieve significant reduction of the required mean acquisition time as compared to general search schemes. ]n addition, the proposed scheme achieves quite good BER performance for large signal-to-noise ratios, which is favorably comparable to the case of ideal perfect timing.

주요국의 화재조사 및 방화수사제도 비교 연구 : 미국, 일본, 영국, 독일, 프랑스와의 비교를 중심으로

김재운 ( Jae Woon Kim ),박형민 ( Hyung Min Bark ),이성기 ( Seong Ki Lee ),이주락 ( Ju Lak Lee ),박노섭 ( Ro Seop Park ),김택수 ( Taek Su Kim ) 한국경찰법학회 2013 경찰법연구 Vol.11 No.1

Because the evidence is burned out in the field of fire events unlike other crimes, it is very difficult to specify a criminal and estimate the fact of an offense. Thus, professional knowledge and a high degree of reasoning are required. It urgently needs to strength investigation skills for fire events in reality that evidence trial based on trial judge is emphasized today. Therefore, it is significant to investigate the actual state of fire and arson investigation system in Korea, identify the problems in the light of systems in advanced countries and propose the implications of fire and arson investigation system of each advanced country. This paper classified the investigation on the fire cause investigation and arson event which was identified to be caused by arson into step-by-step investigation procedures, and investigated how investigation of fire events and arson events is conducted on the focus of fire protection agency and police agency in Korea, the US, Japan, the UK, Germany and France. As a result, responding to fire events in advanced major countries is different based on the social and cultural characteristics, foundation of criminal law and administrative system in each country. Thus, Korea needs to establish the institutional framework to cooperate smoothly in a fire investigation with fire protection agency and police agency based on current situation, broaden the public fire investigation to give expertise, and develop private fire investigation agency such as fire insurance company or private investigators.

대학교 여가스포츠 시설의 효율적 활용 방안

김재운(Chae Woon Kim),조송현(Song Hyeon Cho) 한국사회체육학회 2002 한국사회체육학회지 Vol.17 No.-

The objective of this study is to let college student to make efficient and reasonable use for the school leisure facility ; maintain the facility that has reflected the request of the students, and the facility supervisor to have a reference in facility placement and operation. Through this study people should make a chance to think about the efficient and reasonable use of the facility. From that thinking development of operation should take place. Majority of people should enjoy their university life through using leisure sport facility. To meet those objectives here are plans. First, presenting variety of leisure sport facility and programs for guiding student to participate in sport. From that university culture should get out of unhealthy and unproductive image and become healthy and sound culture. Second, simple leisure sport facility and equipment using small space should take place. For students to have an easy accessible environment to facility or equipment so they could use the facility whenever they feel like using it. Third, user centered administration should be operated. Customer satisfaction should rise by abolishing time limit, so student can use the facility whenever they have time, then usage of facility should rise as well. Forth, publicity about the leisure sport product should take place. Publicity of leisure sport facility using school web site should be a good data. And this should attract majority of students. Fifth, utilizing leisure sport facility for majority should take place. Concept of facility for Athletic clubs and P. E. department only should be disposed. Facility should be open to general student including female, and public.

또래의 신체활동 게임에서의 권력 결정요인 분석

김재운(Chae Woon Kim),권민혁(Min Hyuk Kwon) 한국스포츠사회학회 2002 한국스포츠사회학회지 Vol.15 No.2

해양경비법상 해상검문검색에 관한 연구

김재운 ( Jae Woon Kim ) 한국경찰법학회 2014 경찰법연구 Vol.12 No.1

The maritime police play a role to maintain the peace and order of the ocean in Korea by performing various duties such as maritime safety, prevention and investigation of maritime crimes, search and rescue missions of maritime disasters and prevention of marine pollution in wide areas of the ocean 4.5 times as wide as the land. The rights for boarding, questioning and searching by the maritime police in ships should be explicitly defined in the related Acts in order for the maritime police to lawfully perform their tasks. However, the maritime police have performed them without an explicit legal basis. In 2012, the maritime policing act including the provision of boarding, questioning and searching is enacted to ensure the legality for exercise of maritime police power. Officers having the jurisdiction over land have stopped a criminal suspect and asked questions by means of provision of police questioning in the existing performance of police functions act. However, because the provision of police questioning requires the agreement of subjects, there are many problems in the efficacy of law enforcement. But since there are many risks such as escaping by crossing the border or destroying evidence by throwing it away into the sea, the maritime policing act forcibly enforces the law by imposing a fine if subjects resist the boarding, questioning and searching such as stopping vessel boarding, questioning, and searching by the maritime police. In addition, if a threat is simply imposed on maritime safety without relevance to the crime, it enacts the provision for boarding, questioning and searching in the vessels with unstable navigational state or carrying WMD. But the right of maritime police prescribed by the provision of boarding, questioning and searching by the maritime police in the maritime policing act is miniscule compared to ‘at any time go on board of any vessel subject to … any law of the US’ prescribed by the 14 U.S. Code §89 (a) and ‘the ship is stopped to perform safety examinations or ask questions, if necessary’ prescribed by the Japan Coast Guard Act. Moreover, since we do not have regulations similar to ‘the officers of the Coast Guard … is deemed to be acting as agents of the particular executive department’ prescribed by the 14 U.S. Code §89 (b) and Japan Coast Guard Act 15, we have potential problems of not exercising legal enforcement rights for some acts. If this problem is improved, the maritime police can exercise legal enforcement more effectively in the ocean where potential high-risks are present compared to those in land.

대학생의 교양체육 수강과 동아리활동 참여가 여가태도에 미치는 영향

김재운(Chae Woon Kim) 한국체육교육학회 2001 한국체육교육학회지 Vol.5 No.2

The purpose of this study was to clarify the effects of leisure attitude on physical education as a liberal arts and circle activity among university students. In order to clarify this purpose, 505 university students answered questionnaire which was consists of leisure attitude scale introduced by Ragheb and Beard in 1982. Analysis of Variance(ANOVA) and t-test were the adapted methods to analyze the collected data according to the purpose of this study. The findings of this study were as follows: 1) Man has more behavioral component than woman in the leisure attitude. 2) The times of physical education as a liberal arts effect leisure attitude among university students. In other words, the more participation times of physical education as a liberal arts the more powerful influence upon the leisure attitude. 3) The types of circle activity effect leisure attitude. In other words, the participation group in sports circle has more affective component, behavioral component than any other circle activity in the leisure attitude.