• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.506-506
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• 2000

To improve control performance of a non-linear system, many other researches have used the sliding mode control algorithm. The sliding mode controller is known to be robust against nonlinear and unmodeled dynamic terms. However. this algorithm raises the inherent chattering caused by excessive switching inputs around the sliding surface. Therefore, in order to solve the chattering problem and improve control performance, this study has developed the sliding mode controller with a perturbation estimator using the observer-based fuzzy adaptive network generates the control input for compensating unmodeled dynamics terms and disturbance. And, the weighting parameters of the fuzzy adaptive network are updated on-line by adaptive law in order to force the estimation errors to converge to zero. Therefore, the combination of sliding mode control and fuzzy adaptive network gives rise to the robust and intelligent routine. For evaluating control performance of the proposed approach. tracking control simulation is carried out for the hydraulic motion simulator which is a 6-degree of freedom parallel manipulator.

• 전기학회논문지
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• 제56권5호
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• pp.944-957
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• 2007

In general mechanical servo systems, friction deteriorates the performance of controllers by its nonlinear characteristics. Especially, friction phenomenon causes steady-state tracking errors and limit cycles in position and velocity control systems, even though gains of controllers are tuned well in linear system model. Even if sensor is used higher accuracy level, it is difficult to improve tracking performance of the position to the same level with a general control method such as PID type. Therefore, many friction models were proposed and compensation methods have been researched actively. In this paper, we consider that the variation of mover's mass is various by loading and unloading. The normal force variation occurs by it and other parameters. Therefore, the proposed control system is composed of main position controller and a friction compensator. A parameter estimator for a nonlinear friction model is designed by adaptive control law and adaptive backstopping control method.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1997년도 춘계학술대회논문집; 경주코오롱호텔; 22-23 May 1997
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• pp.413-417
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• 1997

Distributed piezoelectric sensor and actuator have been designed for efficient vibration control of a cantilevered beam. Both PZT and PVDF are used in this study, the former as an actuator and the latter as a sensor for our integrated structure. For the PZT actuator, the position and size have been optimized. Optimal electrode shape of the PVDF sensor has been determined. For multi-mode vibration control, we have used two PZT actuators and a PVDF sensor. Electrode shading of PVDF is more powerful for modal force adjustment than the sizing and positioning of PZT. Finite element method is used to model the structure that includes the PZT actuator and the PVDF sensor. By deciding on or off of each PZT segment, the length and the location of the PZT actuator are optimize. Considering both of the host structure and the optimized actuators, it is designed that the active electrode width of PVDF sensor along the span of the beam. Actuator design is based on the criterion of minimizing the system energy in the control modes under a given initial condition. Sensor is designed to minimize the observation spill-over. Modal control forces for the residual(uncontrolled) modes have been minimized during the sensor design. Genetic algorithm, which is suitable for this kind of discrete problems, has been utilized for optimization. Discrete LQG control law has been applied to the integrated structure for real time vibration control. Performance of the sensor, the actuator, and the integrated smart structure has been demonstrated by experiments.

• 로봇학회논문지
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• 제5권4호
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• pp.349-358
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• 2010

We presents a dynamic modeling of 4-wheel 2-DOF. WMR. The classic dynamic model utilizes a greatly simplified wheel motion representation and using of a simplified dynamic model confronts with a problem for accurate position control of wheeled mobile robot. In this paper, we treats the dynamic model for describes relationship between the wheel actuator force/torque and WMR motion through the use of Newton's equilibrium laws. To calculate the WMR position in real time, we introduced the Dead-Reckoning algorithms and the simulation result show that the proposed dynamic model is useful. We can be easily extend the proposed WMR model to mobile robot of similar type and this type of methodology is useful to analyze, design and control any kinds of rolling robots.

• 수산해양교육연구
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• 제13권2호
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• pp.146-167
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• 2001

Korea and China are two opposite countries located aside Yellow Sea and co-utilize the East China Sea. The two countries are close together from geological point of view, however, the competitive development of resources was more emphasized than the cooperative development of resources between the two countries because the special policy relationship. Additionally, after the communist government of China was founded in 1949, the political conception between the two countries was quite different. Therefore the establishment of appropriate international fisheries co-operation was impossible, and the international management problems of fisheries resources in Yellow Sea and East China Sea were let alone. UN convention on the Law of the Sea came to force in 1994, Korea and China adopted the exclusive economic zone system in 1996. On the other hand, Fisheries Law in Korea was enacted in 1953 in order to management of fisheries resources, and also China was enacted fisheries law in 1986. The two countries control the fisheries effort through fisheries license system, meanwhile through prohibition fishing area, prohibition fishing period, limitation of net size, and limitation of body length to conserve and manage the fisheries resource. The serious management methods of resource management in the two countries are similar such as the creation of promptly decreased species and those species that have commercial value, discharge of fish seedling stock, settlement of artificial reef and clean of fishing ground. Therefore, the two countries should consider not only the improvement of formal law system, but also how to recover the fisheries resources in circumference water zone and how to improve the efficiency of fisheries resource management. Specially the settlement and management of artificial reef should be chosen in the area that have the highest benefit to two countries, and should establish the common management system of discharge of fish seedling stock. And the two countries should adopt the same criteria through technical management and limitation of net size, limitation of body length, and prohibition area of special fisheries to ensure the highest fisheries benefit of fisherman in the two countries and the highest efficiency of fisheries resource management.

• 환경정책연구
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• 제13권4호
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• pp.161-190
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• 2014

나고야 의정서가 평창에서 열리는 UNCBD COP12 기간 중인 2014년 10월 12일에 발효되었다. 이러한 상황에서 본 논문은 나고야 의정서 발효에 따른 쟁점과 외국의 입법례를 분석하여 우리나라 입법안의 개선점을 비롯한 향후 대응 방안에 대해 고찰하였다. 외국의 입법례는 국제환경법 체제 구축에 선도적인 역할을 하는 EU와 대표적인 유전자원 제공국이라 할 수 있는 중국의 입법례를 분석하였다. 이러한 고찰을 통해 우리나라는 나고야 의정서관련 사인과 국가간의 분쟁해결절차 마련과 한중일의 월경성 자원 및 관련 전통지식에 대한 공동 관리를 국제사회에 주장하는 것이 필요하며, 국내적으로는 유전자원 관리 책임기관을 통합하는 방향으로 입법안을 개선하는 것 등이 필요하다.

• 시큐리티연구
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• 제50호
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• pp.307-337
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• 2017

집회의 자유는 헌법에서 보장하고 있는 기본권적 자유이다. 우리의 현실을 보면 집회의 자유는 경찰의 관리통제 하에 있을 때에만 보장되고, 그렇지 않을 때는 진압해야 할 대상으로 인식되고 있다. 심지어 경찰은 '깨진 유리창 이론(broken window theory)'을 거론하면서 조그만 불법이 심각한 불법․폭력시위로 변질될 수 있다는 이유로 집회의 평화성 보다는 '준법'여부에 집착하고 있는 듯한 태도를 보여주고 있다. 이러한 태도는 집회에 참여하는 시민을 진압해야 할 대상으로 내몰게 되는 결과를 초래하고 있다. 이 글은 최근 문제되고 있는 경찰물리력 사용수단으로서 차벽과 물포를 중심으로 물리력 사용요건과 현황을 분석하고, 그 개선방안을 제시하였다. 우선, 차벽의 설치는 집회장소를 항의의 대상으로부터 분리시킴으로써 집회가 갖는 본질적인 소통의 기능을 차단하고 있다. 따라서 차벽설치는 불법행위에 직면하여 예방을 위한 경고에도 불구하고 차벽설치 이외 다른 방법으로는 '사람의 생명 신체에 위해를 끼치거나 재산에 중대한 손해를 끼칠 우려가 있는 긴급한 경우'에 한하여 허용되어야 할 것이다. 이러한 긴급성이 없다면 차벽은 사전예방적 차원뿐만 아니라 사후예방적 차원에서도 허용되어서는 안된다. 물포는 사람의 생명․신체에 위해를 가할 우려가 있는 경찰장비로서 기본권의 중대한 제한을 가져오는 강제조치이다. 따라서 사람의 신체에 중대한 위험을 초래할 수 있는 조준 직사살수는 원칙적으로 금지되어야 한다. 다만 그 위험성을 고려하여 타인의 법익이나 공공의 안녕질서에 직접적인 위험이 '명백하게 초래'된 경우에 한하여 다른 대안이 없는 경우에 보충적으로 사용하여야 한다. 아울러 그 사용기준 등에 대해서는 물포가 위해성 경찰장비인 점을 고려하여 법률로 명시해야 한다.

• 시큐리티연구
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• 제26호
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• pp.59-87
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• 2011

경비업법의 주요 내용을 살펴보면, 경비업에 대한 규제적 측면에 치우쳐 있으며, 구체적인 권한 부여에 관한 규정이 명확히 제시되어 있지 않다. 이것은 경비업무을 실질적으로 수행하고 있는 경비원의 권한에 대한 근거 규정의 미비와 그러한 권한의 한계를 명확히 설정하지 못하는 문제를 야기하게 된다. 이에 따라 경비업법상 경비업 주체의 업무 수행의 한계를 부여함과 동시에 경비업무의 원활한 수행을 담보할 수 있는 권한 근거 규정을 도출할 수 있는 해석이 이루어져야 하며, 그러한 단서를 제공하는 것이 경비업법 제7조 제1항의 "관리권"이라 할 수 있다. 경비업법에 규정된 관리권의 범위에는 점유권에 기한 자력구제권을 근거로 하여 자력방위 및 자력탈환권이 포함되며, 사실적 지배행위로서 정지 및 질문권, 출입통제 및 퇴거요구권, 물품 검색 반입 보류 및 금지권 등이 인정된다고 할 것이다. 점유보조자의 지위에서 경비원은 관리권으로부터 도출될 수 있는 사전예방 활동을 할 수 있으며, 이러한 예방활동에도 불구하고 법익 침해가 예상되거나 이루어진 경우 관리권에 근거하여, 소극적 저항행위와 저항수단으로서의 유형력 범위 안에서 실력으로 침해를 저지 할 수 있다. 그리고 그러한 물리적 유형력을 행사하기 위해서는 형법상 위법성조각사유인 정당방위 긴급피난 정당행위의 요건을 구비하여야 한다.

• Journal of Preventive Medicine and Public Health
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• 제47권3호
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• pp.129-135
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• 2014

Tobacco use is the most important preventable risk factor for premature death. The World Health Organization (WHO) Framework Convention on Tobacco Control (FCTC), the first international public health treaty, came into force in 2005. This paper reviews the present status of tobacco control policies in Korea according to the WHO FCTC recommendations. In Korea, cigarette use is high among adult males (48.2% in 2010), and cigarette prices are the lowest among the Organization for Economic Cooperation and Development countries with no tax increases since 2004. Smoke-free policies have shown incremental progress since 1995, but smoking is still permitted in many indoor public places. More than 30% of non-smoking adults and adolescents are exposed to second-hand smoke. Public education on the harmful effects of tobacco is currently insufficient and the current policies have not been adequately evaluated. There is no comprehensive ban on tobacco advertising, promotion, or sponsorship in Korea. Cigarette packages have text health warnings on only 30% of the main packaging area, and misleading terms such as "mild" and "light" are permitted. There are nationwide smoking cessation clinics and a Quitline service, but cessation services are not covered by public insurance schemes and there are no national treatment guidelines. The sale of tobacco to minors is prohibited by law, but is poorly enforced. The socioeconomic inequality of smoking prevalence has widened, although the government considers inequality reduction to be a national goal. The tobacco control policies in Korea have faltered recently and priority should be given to the development of comprehensive tobacco control policies.

• Smart Structures and Systems
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• 제20권5호
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• pp.525-537
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• 2017

This paper explores different vibration control strategies for the cancellation of human-induced vibration on a structure with time-varying modal parameters. The main motivation of this study is a lively urban stress-ribbon footbridge (Pedro $G\acute{o}mez$ Bosque, Valladolid, Spain) that, after a whole-year monitoring, several natural frequencies within the band of interest (normal paring frequency range) have been tracked. The most perceptible vibration mode of the structure at approximately 1.8 Hz changes up to 20%. In order to find a solution for this real case, this paper takes the annual modal parameter estimates (approx. 14000 estimations) of this mode and designs three control strategies: a) a tuned mass damper (TMD) tuned to the most-repeated modal properties of the aforementioned mode, b) two semi-active TMD strategies, one with an on-off control law for the TMD damping, and other with frequency and damping tuned by updating the damper force. All strategies have been carefully compared considering two structure models: a) only the aforementioned mode and b) all the other tracked modes. The results have been compared considering human-induced vibrations and have helped the authors on making a decision of the most advisable strategy to be practically implemented.