• 한국지능시스템학회논문지
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• 제21권2호
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• pp.159-164
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• 2011

본 연구에서는 4절 링크 이론(four-bar linkage mechanism)과 얀센 메커니즘(Jansen mechanism)을 기반으로 다관절 보행 로봇(multi-legged walking robot)인 게(crab) 로봇을 제작하고, 게 로봇의 움직임에 대하여 기구학적인 해석을 제시한다. 제작된 게 로봇은 영상 획득을 위하여 카메라를 장착하였고, 장애물 회피를 위하여 3조의 초음파 센서를 가지고 있다. 또한 RF통신으로 외부에 영상 정보를 전달하며, Blue-tooth 통신 모듈을 장착하여 외부로부터 부여된 임무를 수행할 수 있다. 게 로봇의 설계와 제작을 하기 위해서 필요로 하는, 로봇 다리의 움직임을 알기 위해서는 관절 변수와 다리 끝단의 위치 및 자세와의 관계를 얻어야 한다. 따라서, 제안된 기구학적 해석은 로봇의 설계와 제작에 있어서 많은 도움을 주며 중요한 과정이다.

• 한국항공우주학회지
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• 제48권5호
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• pp.343-354
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• 2020

쌍안정 장치는 서로 다른 두 가지 상태에서 안정성을 갖는 시스템이며, 구동에 있어 에너지 효율 측면에서 이득을 얻을 수 있다. 이러한 쌍안정 장치는 다양한 방법을 통해 구현되며, 전개형 구조물, 스위치 시스템 그리고 파지 로봇 등, 주된 동작이 두 종류로 구분되는 모핑 시스템에 적용될 수 있다. 하지만 기존 장치들의 복잡성과 구조적 제한 때문에, 링크 구조물처럼 회전하는 구조를 포함하는 모핑 시스템을 구현하는 것은 어려움이 존재한다. 본 연구에서는 원통형 영구자석을 이용하여 회전운동에 있어 쌍안정성을 갖는 장치를 구현하는 방법이 제안된다. 원통형 영구자석의 전자석 모델을 도입하여 자기장과 자기력을 도출했으며, 이를 이용하여 원통형 영구자석을 포함하는 두 링크 사이의 힘 관계를 추정했다. 대칭 쌍안정성을 위한 원통형 영구자석의 배열을 선정했으며, 제안하는 쌍안정 장치를 회전 조인트로 연결된 링크 구조물에 적용하여 외부 토크에 대한 안정성을 실험을 통해 확인하였다.

• 한국소음진동공학회논문집
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• 제19권10호
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• pp.1053-1061
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• 2009

The goal of this paper is to investigate the generation characteristics of the main impulsive noise sources generated by the supersonic flow discharging from a muzzle. For this, this paper investigates two fundamental mechanisms to sound generation in shocked flows: shock motion and shock deformation. Shock motion is modeled numerically by examining the interaction of a sound wave with a shock. The numerical approach is validated by comparison with results obtained by linear theory for a small disturbance case. Shock deformations are modeled numerically by examining the interaction of a vortex ring with a blast wave. A numerical approach of a dispersion-relation-preserving(DRP) scheme is used to investigate the sound generation and propagation by their interactions in near-field.

• 한국언어정보학회:학술대회논문집
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• 한국언어정보학회 2002년도 Language, Information, and Computation Proceedings of The 16th Pacific Asia Conference
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• pp.227-236
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• 2002

Japanese coordinate noun phrases by the particle TO are often ambiguous on whether it means two parallel propositions (and), or a mutual case relation (with or against), as deep case structure. It was a hard problem to determine it, though they are widely used. We propose a method of solving the ambiguity by analyzing mutualness of verbs and adjectives. The mutualness is determined by three features of each verb or adjective. The first feature Indicates permission of mutual expression in the subject, and the second In the object. The last shows if a verb is voluntary. Using this method we design a parsing mechanism, where matching of features is represented as neutralization between predicate arguments.

• ETRI Journal
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• 제34권4호
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• pp.591-601
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• 2012

Unstructured peer-to-peer (p2p) networks usually employ flooding search algorithms to locate resources. However, these algorithms often require a large storage overhead or generate massive network traffic. To address this issue, previous researchers explored the possibility of building efficient p2p networks by clustering peers into communities based on their social relationships, creating social-like p2p networks. This study proposes a social relationship p2p network that uses a measure based on Hebbian theory to create a social relation weight. The contribution of the study is twofold. First, using the social relation weight, the query peer stores and searches for the appropriate response peers in social-like p2p networks. Second, this study designs a novel knowledge index mechanism that dynamically adapts social relationship p2p networks. The results show that the proposed social relationship p2p network improves search performance significantly, compared with existing approaches.

• 한국생산제조학회지
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• 제25권2호
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• pp.143-148
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• 2016

A micro end mill is one of the precise tools used in machining ultra-precision products such as microchannel and micropatterned mold. To achieve the required precision of these products, several studies investigated the cutting force, burr formation, and burr generation mechanism of micro end mills; however, there are few studies on the alignment of micro tools, which is the foundation of machining. Hence, in this investigation, relation expressions were derived to determine the relation between the misalignment parameters and the machining accuracy. At the same time, the effect of the machining parameters was analyzed using a multiple linear regression analysis and the analysis of variance. The results indicate that the tilting angle of a micro tool has more influence on the machining accuracy than other parameters.

• 대한한의학회지
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• 제26권2호
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• pp.126-139
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• 2005

Objective: This study was undertaken to examine the reliability of disease mechanism diagnosis, estimate the disease mechanism items of questionnaires and inquire about the relation of disease mechanisms to the oriental OB & GY diagnosis program. Questionnaires and abridged questionnaires were used for the object diagnosis of oriental medicine in the dept of Oriental OB & GY, Oriental Medical Hospital of Dong-Eui University. Methods: We analyzed the results of questionnaires about 1706 outpatients who had OB & GY disease in the Oriental Medical Hospital of Dong-Eui University from April 2000 to March 2004. Results: 1. The reliability of Oriental OB & GY questionnaires between $90\%$ and $95\%$ were 9 cases, between $85\%$ and $90\%$ were 3 cases, and under $85\%$were 3 cases. Abridged questionnaires were lower than original questionnaires, but 12 cases of a total 15 cases of disease mechanism were above $85\%$. Therefore, both abridged questionnaires and original questionnaires had similar results. 2. Abridged questionnaires were usually lower than existing questionnaires in the comparison of disease mechanism output frequency and that of disease mechanism average score. Therefore, the results of abridged questionnaires seemed to be poorer than those of existing questionnaires, but a great difference wasn't seen. 3. Disease mechanism that was over $50\%$ in the rate of pure question per disease mechanism was 10 cases $(66.7\%)$. Disease mechanism that contributed to producing disease mechanism result and in which pure question was over relevance calculation 0.9 was also 10 cases $(66.7\%)$. In abridged questionnaires, the duplication of questions per disease mechanism Was decreased, the rate of pure questions was increased, and the number of related disease mechanisms was decreased by abridgment of the questionnaires' questions. 4. The calculation of disease mechanism went with the increase of the duplication of questions in many cases, but Tam­Umhe, Kihe-Hyule, Kihe-Umhe, and Shin-Tam went with disease mechanism in many cases despite no duplication of questions. Conclusions: About the reliability of Oriental OB & GY questionnaires, 12 of a total 15 cases of disease mechanism were above $85\%$; therefore both abridged questionnaires and original questionnaires had similar results.

• 대한감각통합치료학회지
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• 제1권1호
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• pp.61-72
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• 2003

The suck/swallow/breathe(SSB) synchrony, serving as the earlist primary motor mechanism, is the rhythmical, coordinated pattern of sucking, swallowing and breathing. The development of an intact SSB is an important precursor for further sensorimotor and cognitive development including speech and language development, state regulation, postural control, feeding, eye/hand coordination and social/emotional development. Arousal means a neurological mechanism for preparing one's body to orienting stimulus. Its levels are regulated with an interaction of the reticular formation, the limbic system, the hypothalamus and the autonomic nervous system. General strategies such as blowing, sucking, chewing, munching and licking to effectively modulate arousal state are related to SSB. The SSB synchrony is an important treatment principle for children with sensory integration disorder and problems with the modulation of arousal. The purpose of this article is to review concepts of SSB synchrony and the underlying relation between the modulation of arousal and SSB synchrony.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.1035-1040
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• 2011

In this paper we deal with a kinetic performance test system using hydraulic cylinder. It is possible to measure only current using the conventional electro-mechanical actuator when the bogie is in the process of the tilting. This makes impossible to measure the force acting on the tilting actuator. In order to overcome this problem a kinetic performance test system using hydraulic cylinder is proposed. The proposed system provide easy kinetic evaluation for the tilting mechanism and evaluation for the co-relation between load acting on the tilting actuator and the moving displacement(strock) of the tilting actuator.

• Journal of Welding and Joining
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• 제19권3호
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• pp.298-304
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• 2001

Turbine blade is subject to force of three types ; the torsional force by torsional mount, the centrifugal force by the rotation of rotor and the cyclic bending force by steam pressure. The cyclic bending force was a main factor on fatigue strength. SEM fractography in root of turbine blade showed micro-clack width was not dependent on stress intensity factor range. Especially, fatigue did not exist on SEM photograph in root of turbine blade. To clear out the fracture mechanism of turbine blade, nanofractography was needed on 3-dimensional crack initiation and crack growth with high magnification. Fatigue striation partially existed on AFM photograph in root of turbine blade. Therefore, to find a fracture mechanism of the torsion-mounted blade in nuclear power plant, the relation between stress intensity factor range and surface roughness measured by AFM was estimated, and then the load amplitude ΔP applied to turbine blade was predicted exactly by root mean square roughness.