화재조사를 위한 방화탐지견 도입 필요성 연구

최영진(Youngjin Choi),최승복(Seungbok Choi),윤광상(Gwangsang Yoon),장세용(Seyong Jang),조재만(Jeman Cho),전용기(Yonggi Jeon),최돈묵(Donmok Choi) 반려동물연구학회 2019 Animalia Vol.1 No.1

화재현장은 살인, 방화, 절도, 보험범죄 등 모든 강력 범죄가 묻혀있을 수 있다. 그러기 때문에 무엇보다 세심한 현장조사가 요구된다. 인명피해가 발생한 현장, 사회 이 목이 집중된 대형화재 그리고 다액 화재보험이 가입된 화재 현장일 경우 경찰은 화재 원인 조사에 많은 인력과 시간을 할애하여 정확한 발화 원인과 인명피해가 발생하게 된 원인을 조사하여야 한다. 화재 원인이 확인되지 않으면 수사의 방향 설정이 어렵고 또한 살인사건과 같은 강력 범죄가 잿더미 속에 묻혀 단순 화재사고로 처리될 수 있다. 하지만 한국 화재조사는 삽, 호미와 같은 기본적인 발굴 장비와 조사자의 시각·후각·촉각 등 오감에 의존하고 있는 실정으로 보다 과학적이고 새로운 화재조사 기법 도입이 요구되는 시점이다. 방화범은 일반적으로 인화성물질과 같은 촉진제를 사용하여 짧은 시간에 건물이나 목적물을 소훼시키려고 한다. 화재현장에 뿌려진 인화성물질은 연소 이후 대부분 연소되거나 증발하여 잔해 속에 묻혀 있는 미량의 촉진제를 조사관의 후각이나 가스검지기와 같은 장비로 이를 찾아낸다는 것은 기대하기 어렵다. 본 연구는 인간보다 2억 배의 후각이 뛰어난 방화탐지견을 화재현장에 투입하여 신속한 방화범죄 판단과 수사 방향 결정 등에 활용함으로써 경찰 수사의 신뢰와 질을 향상시키길 제안한다. All kinds of violent crimes, such as murder, arson, theft, and even insurance crime, can be buried in a scene of fire. Thus, minute examination and careful investigation is required in every fire scene. Especially, some fire scenes, which, for example, cause numerous casualties, attract a social attention because of its massive conflagration, or are related to heavy insurance, need to put much more effort into precise investigation. If the cause of the fire is not clearly defined, it may not only result in difficulty for establishing investigation strategy, but also produce misleading result as a simple accident. Still, a fire scene investigation practice in Korea is relying on either basic excavation devices such as a hoe, or simply investigator"s senses. Accordingly, it is definitely prime time for Korea to develop a new, high-tech forensic practice for a fire scene investigation. Since most arsonists have a purpose to burn down the target as fast as possible by using accelerators or inflammables, and those substances easily evaporate, it is hard to search out accelerators of inflammables in a fire scene, mererly depending on investigator"s olfactory sense or gas meter. This study suggests a direction to improve the standard of police investigation in terms of handling arson crime scene with practical use of arson K-9 dogs, whose sense of smell is outstandingly superior to humans"s.

Okamoto - Uchiyama 확률 공개키 암호 방식의 효율성 개선

최덕환(Dug-Hwan Choi),김현주(Hyun-jue Kim),최승복(Seungbok Choi),원동호(Dong-ho Won) 한국정보과학회 2002 정보과학회논문지 : 정보통신 Vol.29 No.4

본 논문은 Okamoto와 Uchiyama가 이산대수 함수만으로 일방향함수를 정의하여 제안한 새로운 확률 공개키 암호 방식을 개선하였다. 평문은 이들 두 이산대수 함수의 모듈라 곱으로부터 구할 수 있는데 두 함수 값 중에서 하나는 주어진 공개키에 종속된 고정된 값을 가진다. 고정된 함수 값이 단위원 1을 갖는 정선된 공개키에 의해 개선이 이루어진다. 왜냐하면 복호화 할 때 계산량을 줄일 수 있기 때문이다. 또한 이러한 성질을 충족하는 공개키를 얻을 수 있는 구체적 방법도 제시한다. We improve a new probabilistic public key cryptosystem, in which the one way function was defined only on the discrete logarithmic functions, proposed by Okamoto and Uchiyama. The plaintexts are calculated from the modular product of two these functions, one of which has a fixed value depending on a given public key. The improvement is achieved by a well-chosen public key assuming an unit element 1 as the fixed function value. Because it is possible to reduce the number of operations at the decryption. Also the concrete method for a public key of our improved scheme is suggested.

퍼지-이동슬라이딩모드 제어기를 이용한 ER 현가장치의 제어

조재완(Jaewan Cho),최승복(Seungbok Choi),정시영(Siyoung Jung) 한국자동차공학회 2005 한국자동차공학회 춘 추계 학술대회 논문집 Vol.2005 No.11_2

This paper presents a robust and superior control performance of a quarter-vehicle electrorheological (ER) suspension system. In order to achieve this goal, a moving sliding mode control algorithm is adopted, and its moving strategy is tuned by fuzzy logic. As a first step, ER shock absorber is designed and manufactured for a commercial suspension system, and its field-dependent damping force is experimentally evaluated. After formulating the governing equation of motion for the quarter-vehicle ER suspension system, a stable sliding surface and moving algorithm based on fuzzy logic are formulated. The sliding mode controller is then synthesized and control performance such as vertical displacement is evaluated in time domain.

MR 충격 댐퍼를 이용한 차량 충돌 저감에 관한 연구

우다윗(David Woo),최승복(Seungbok Choi) 한국자동차공학회 2005 한국자동차공학회 춘 추계 학술대회 논문집 Vol.2005 No.11_3

This paper presents performance characteristics of a MR impact damper for controllable bumper in vehicle systems. Recently, several mechanisms are proposed in order to minimize the injury of vehicle occupants during frontal collision. One of promising candidates is to adopt MR fluid which undergoes significant instantaneous reversible changes in material characteristics when subjected to magnetic field. Using this salient property, a new type of MR impact damper is devised in this work. The proposed MR impact damper is integrated with bellows to induce the flow motion and the motion is operated under flow mode. In order to demonstrate the effectiveness of the proposed impact damper, a lumped parameter mathematical model of frontal vehicle crash system including MR impact damper is developed and realized in order to evaluate acceleration peak reductions in the frontal collision.

ER 댐퍼를 이용한 차량 현가장치 시스템의 이산시간 퍼지 슬라이딩 모드 제어

임계현(Kyehyun Lim),최승복(Seungbok Choi) 한국자동차공학회 2005 한국자동차공학회 춘 추계 학술대회 논문집 Vol.2005 No.11_2

This paper presents control characteristics of a quarter-vehicle electrorheological(ER) suspension system by adopting a discrete-time fuzzy sliding mode control algorithm. A cylindrical ER damper is designed and manufactured by incorporating Bingham model of the ER fluid. After evaluating the field-dependent damping characteristics of the ER damper, a quarter-vehicle ER suspension system is constructed which is composed of sprung mass, ER damper, spring and tire. After deriving the governing equation of motion for the quarter-vehicle ER suspension system, a discrete-time control model with system uncertainties is formulated in a state space. A stable sliding surface is then designed followed by the formulations of a discrete-time sliding mode controller which consists of a discontinuous part and an equivalent part. In the controller formulation, the fuzzy control algorithm is also adopted to increase system robustness to the uncertainties and achieve faster reaching to the sliding surface. The controller is then realized and control performance is compared with the performance of continuous-time sliding mode controller.

시상수와 시스템 불확실성을 고려한 ER 댐퍼의 댐핑력 제어

배광식(Kwangsik Bae),최승복(Seungbok Choi) 한국자동차공학회 2003 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

This paper presents an electro-rheological(ER) suspension system for a passenger vehicle considering time response and system uncertainties. An appropriate size of ER damper is designed and manufactured on the basis of Bingham model, and its field-dependent damping force characteristics are experimentally evaluated. The time response of ER damper is identified and integrated with the 1/4 car suspension model. In addition, the variation of the sprung mass is considered as well as the variation of the yield stress of ER fluid. A semi-active skyhook controller is designed and implemented associated with the hardware-in-the-loop simulation. Control responses of the proposed ER suspension system are evaluated under various road conditions.

ER 밸브를 이용한 자동차 ABS 의 슬라이딩 모드 제어

김용일(Yongil Kim),조명수(Myungsoo Cho),최승복(Seungbok Choi) 한국자동차공학회 2003 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

The anti-lack brake system(ABS) is designed to optimize braking effectiveness and maintain steerability. In this study a new anti-lack brake(ABS) using Electro-Rheological(ER) valve is proposed for passenger vehicle. In the proposed ER ABS, ER valve substitutes far solenaid valve af conventianal ABS. The design parameters of the ER valve are appropriately determined by considering the braking pressure required for a passenger vehicle. The sliding made controller(SMC) which has inherent robustness to system uncertainties are formulated for wheel slip control. The ER ABS is evaluated under various road conditions with 1/4 car model.<br/>

인체진동모델을 이용한 ER 시트 현가장치의 슬라이딩모드 제어

정진영(Jinyoung Jung),한영민(Youngmin Han),최승복(Seungbok Choi) 한국자동차공학회 2003 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

This paper presents robust control performance of a semi-active ER(electro-rheological) seat suspension. A cylindrical type of ER seat damper is designed and manufactured for a commercial vehicle. The governing equation is derived from 6-DOF seat-driver model and the obtained seat-driver model is reduced through balanced model reduction. A sliding mode controller is then designed with full-order state observer and experimentally realized where a driver is sitting on controlled seat. Control performances are evaluated in both time and frequency domains. In addition, comparative work between ER seat suspension and conventional passive suspension is undertaken with ride quality criteria.