• Korean Journal of Materials Research
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• v.32 no.6
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• pp.301-306
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• 2022

This study explored the possibility of forming a coating layer containing alginic acid on the surface of a magnesium alloy to be used as a biomaterial. We formed a coating layer on the surface of a magnesium alloy using a plasma electrolytic oxidation process in an electrolytic solution with different amounts of alginic acid (0 g/L ~ 8 g/L). The surface morphology of all samples was observed, and craters and nodules typical of the PEO process were formed. The cross-sectional shape of the samples confirmed that the thickness of the coating layer became thicker as the alginic acid concentration increased. It was confirmed that the thickness and hardness of the sample significantly increase with increasing alginic acid concentration. The porosity of the surface and cross section tended to decrease as the alginic acid concentration increased. The XRD patterns of all samples revealed the formation of MgO, Mg₂SiO₄, and MgF₂ complex phases. Polarization tests were conducted in a Stimulate Body Fluid solution similar to the body's plasma. We found that a high amount of alginic acid concentration in the electrolyte improved the degree of corrosion resistance of the coating layer.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.124-127
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• 1997

In this paper, we propose a method of cooperative control based on immune system in distributed autonomous robotic system(DARS). Immune system is living body's self-protection and self-maintenance system. Thus these features can be applied to decision making of optimal swarm behavior in dynamically changing environment. For the purpose of applying immune system to DARS, a robot is regarded as a B lymphocyte(B cell), each environmental condition as an antigen, and a behavior strategy as an antibody respectively. The executing process of proposed method is as follows. When the environmental condition changes, a robot selects an appropriate behavior strategy. And its behavior strategy is simulated and suppressed by other robot using communication. Finally much simulated strategy is adopted as a swarm behavior strategy. This control scheme is based on clonal selection and idiotopic network hypothesis. And it is used for decision making of optimal swarm strategy.

• Proceedings of the Korean Information Science Society Conference
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• 2012.06d
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• pp.246-248
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• 2012

In this paper, we recommend some game theoretical schemes try to get reliability transmission and resource allocation of the contention free period in overlapped WBAN(Wireless Body Area Net works) environment. Cooperative bargaining game is considered to guarantee a reliability conflict-free transmission. We study it by considering the priorty of device and the demand number of allocated timeslots in the CFP (Contention Free Period), and guarantee the least requested timeslots through bargaining between each user.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.161.2-161
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• 2001

To achieve a cooperative work between human and robot, it is thought helpful to estimate the states of human mind, which originates his behavior. In this paper, human mind was considered to modify instinctive desires according to the conditions of external world surrounding the instinct. A simple human mind model was designed so that it finds a balance between instinctive desire and restriction from the external world. The external world is divided into three sub-worlds like subject´s whole body, its partner and concerned periphery. Proposed mind model has three-layers construction. Each of the layer tries to find a balance between desire and restriction from external world. In each layer, the role of finding the balance was expressed by an identical optimal control minimizing a performance index function of quadratic form with a weight factor, which is rearranged and named ...

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.2
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• pp.215-219
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• 1999

This study aims to make detail examination of smallholder dairy farming systems in the Nongpho Dairy Cooperative. Forty-three dairy farms were selected from three geographical areas i.e. irrigated area, municipality area, and factory area. Within each area some number of sample farms were selected from each of the three levels of farm and animal crowdedness (very crowded, crowded, and not crowded farms). Detail data were collected during 1996 to 1997, they were socio-economic conditions of the sample farms and farmers, dairy production systems and management of resources (animals, bam, feeds, stocking rates, herd structure, animal body conditions, milk yield and milk quality, manure and farm wastes management, and other related items). Detail information useful for the improvement of farm production efficiency were discussed. It was very clear that much improvement of smallholder dairy production can be achieved if the recommendations given by this study were implemented.

• Proceedings of the Korean Information Science Society Conference
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• 2011.06d
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• pp.221-224
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• 2011

본 논문에서는 중첩 된 WBAN(Wireless Body Area Network) 환경에서 비경쟁 전송구간의 신뢰성 있는 전송을 위해 한정된 자원(비경쟁 전송구간)을 각각의 WBAN에게 할당하는 방안을 제안한다. 이를 위해 협동적 게임 이론(cooperative game theory)을 바탕으로 한정된 자원(비경쟁 전송구간)을 효율적이고 공평하게 할당 할 수 있도록 내쉬중재(Nash arbitration) 기법을 통한 자원 할당 방안을 살펴본다. 내쉬중재 협상해법을 통해 WBAN 간 비경쟁 전송구간의 충돌 없이 신뢰성 있는 전송을 보장한다. 또한, 각 WBAN의 비경쟁 전송 구간 내의 디바이스 우선순위와 할당받은 timeslot의 개수를 고려하여 전략 선택에 따른 형평성과 각 WBAN이 비경쟁전송 구간 내에 요구하는 최소한의 timeslot을 보장한다.

• Information and Communications Magazine
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• v.28 no.12
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• pp.50-60
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• 2011

Visible light communication(VLC) is one type of short-range, optical, and wireless communication system utilizing light emitting diode(LED) and laser diode(LD) as optical source. In a VLC system, visible light is used as a transmission medium and used to illuminate. Using VLC has a lot of advantages: it is harmless to human body; it transmits with high power, and it has excellent security, a high data rate, and a license free frequency band. With such a unique blend of communication and illumination in one system, the most common application would be an indoor environment. We aim at reviewing key issues in VLC network such as : FOV(field of view), priority MAC, cooperative MAC, link switching, LED-ID technique, cell site diversity, and link recovery.

• Development and Reproduction
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• v.25 no.4
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• pp.321-326
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• 2021

The purpose of this paper is to critique the links between science and scientific researchers, politics and capital surrounding vaccines and vaccination in a pandemic era. It also introduces standards for adapting ethical guidelines for research under public health emergencies to specific circumstances and contexts. It also introduces ethical standards to be applied to scientific research. that is, scientific relevance, social value, cooperative partnerships, reasonable risk-benefit costs, fair and voluntary participation, independent review, and equal moral respect for participants and affected communities. It also outlines the COVID-19 (coronavirus disease 2019) pandemic-consent and other research procedure modifications proposed by Oregon Health and Science University (OHSU). We are on the lookout for powerful capital and hegemonic groups inseparable from politics and important decision makers in the pandemic era - that is, scientists, supporters, and scientific civic groups. It underscores the need for an independent and formal scientific advisory body with the right balance between science and politics.

• Journal of the Korean Institute of Intelligent Systems
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• v.9 no.6
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• pp.627-633
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• 1999

In this paper, we propose a method of cooperative control (T-cell modeling) and selection of group behavior strategy (B-cell modeling) based on immune system in distributed autonomous robotic system (DARS). Immune system is living body's self-protection and self-maintenance system. These features can be applied to decision making of optimal swarm behavior in dynamically changing environment. For applying immune system to DARS, a robot is regarded as a ？3-cell, each environmental condition as an antigen, a behavior strategy as an antibody and control parameter as a T-cell respectively. When the environmental condition (antigen) changes, a robot selects an appropriate behavior strategy (antibody). And its behavior strategy is stimulated and suppressed by other robot using communication (immune network). Finally much stimulated strateby is adopted as a swarm behavior strategy. This control scheme is based on clonal selection and immune network hypothesis, and it is used for decision making of optimal swarm strategy. Adaptation ability of robot is enhanced by adding T-cell model as a control parameter in dynamic environments.

• Journal of Oriental Neuropsychiatry
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• v.12 no.1
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• pp.219-229
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• 2001

The brainstem include midbrain, pons & medulla. In acute stage of brainstem infarction, neurologic symptoms may be progressive. So we must pay special attention to Wallenberg's syndrome. In other words, Wallenberg's syndrome is dorsolateral medullary syndrome. A-54-years-old woman was admitted because of vertigo, ataxia & somatic sensory loss of left face and right half-body. Brain MRI showed high SI in T2W, low SI in T1W lesion left medullary infarction. We diagnosed the case as Shin-heo type Oriental medically and prescribed Gihwangemjakamibang. Diabetes mellitus was found out. So We have controlled diabetes mellitus by Occidental medical therapy. In the end, The symptoms of the patient became better. We know that cooperative(oriental & occidental) medical therapy is better than one medical therapy.Here we present one case of Wallenberg's syndrome who was admitted at Kunpo Wonkwang University Hospital Oriental Neuropsychiatry from 14th March to 6th April. 2001.