• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2003년도 가을 학술논문집
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• pp.388-394
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• 2003

밀폐 및 차폐 공간을 갖는 핫셀에서 사용후핵연료와 같은 고방사선 물질을 취급하고 있으며, 핵주기시설에서 마스터-슬레이브 매니퓰레이터는 원격취급장비로서 널리 사용되고 있다. 본 연구에서는 차세대관리공정의 디지털 목업을 구축하고 원격유지보수를 위한 매니퓰레이터의 작업영역 및 작업분석을 수행하였다. 실제 환경과 동일한 가상 작업환경을 갖는 디지털 목업은 3차원 그래픽으로 모델링 된 공정장치 및 원격 취급장비들로 구성된다. 모델링 된 매니퓰레이터는 기구학 및 동작범위에 대한 속성을 부여되고 외부 입력장치는 space ball을 사용하여 매니퓰레이터의 동작을 구현하였다. 또한, Tele-operation 인터페이스를 사용하여 6축 외부 입력장치와 연계한 시스템을 개발하였으며 외부 입력에 따른 매니퓰레이터의 동작에 대한 동기는 만족할 만한 응답을 보였다. 이는 가상환경에서 작업자 교육을 위한 시스템 개발에 유용할 것이다.

• International Journal of Railway
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• 제6권2호
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• pp.33-44
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• 2013

In recent years, energy consumption in the transportation sector by expanding motorization continues to increase in almost every country in the world. Moreover, the growth rate of the transportation energy consumption is significantly higher than those of the civilian and industrial sectors. Therefore, every country strives to reduce its dependence on private transport, which is the main contributor to the transportation energy consumption. In many countries, concepts such as Transit Oriented Development (TOD) or New Urbanism, which controls road traffic by increasing the proportion of the public transportation significantly, have been implemented to encourage a modal shift to public transport. However, the level of change required for eliminating environmental problems is a challenging task. Minimizing transportation energy consumption by controlling the increase of the traffic demand and maintaining the level of urban mobility simultaneously is a pressing dilemma for each city. Grasping the impact of the diversity of the urban transport and infrastructure is very important to improve transportation energy efficiency. However, the potential for reducing urban transportation energy consumption has often been ineffectively demonstrated by the diversity of cities. Therefore, the accuracy of evaluating the current efficiency rate of the urban energy consumption is necessary. Nevertheless, quantitative analyses related to the efficiency of transportation energy consumption are scarce, and the research on the current condition of consumption efficiency based on international quantitative analysis is almost nonexistent. On the basis of this background problem definitions, this research first built a database of the transportation energy consumption of private modes in 119 cities, with an attempt to reflect individual travel behaviors calculated by Person Trip data. Subsequently, Data Envelopment Analysis (DEA) was used as an assessment method to evaluate the efficiency of transportation energy consumption by considering the diversity of the urban traffic features in the world cities. Finally, we clarified the current condition of consumption efficiency by attempting to propose a target values for improving transportation energy consumption.

• 한국통신학회논문지
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• 제39C권9호
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• pp.820-827
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• 2014

One of the basic problems in Wireless Sensor Networks (WSNs) is the localization of the sensor nodes based on the known location of numerous anchor nodes. WSNs generally consist of a large number of sensor nodes and recording the location of each sensor nodes becomes a difficult task. On the other hand, based on the application environment, the nodes may be subject to mobility and their location changes with time. Therefore, a scheme that will autonomously estimate or calculate the position of the sensor nodes is desirable. This paper presents an intelligent localization scheme, which is an artificial neural network (ANN) based localization scheme used to estimate the position of the unknown nodes. In the proposed method, three anchors nodes are used. The mobile or deployed sensor nodes request a beacon from the anchor nodes and utilizes the received signal strength indicator (RSSI) of the beacons received. The RSSI values vary depending on the distance between the mobile and the anchor nodes. The three RSSI values are used as the input to the ANN in order to estimate the location of the sensor nodes. A feed-forward artificial neural network with back propagation method for training has been employed. An average Euclidian distance error of 0.70 m has been achieved using a ANN having 3 inputs, two hidden layers, and two outputs (x and y coordinates of the position).

• 디지털콘텐츠학회 논문지
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• 제5권1호
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• pp.22-27
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• 2004

밀폐 및 차폐 공간을 갖는 핫셀에서 사용후핵연료와 같은 고방사선 물질을 취급하고 있으며, 핵주기시설에서 마스터-슬레이브 매니퓰레이터는 원격취급장비로서 널리 사용되고 있다. 본 연구에서는 차세대관리공정의 디지털 목업을 구축하고 원격유지보수를 위한 매니퓰레이터의 작업영역 및 작업분석을 수행하였다. 실제 환경과 동일한 가상 작업환경을 갖는 디지털 목업은 3차원 그래픽으로 모델링된 공정장치 및 원격 취급장비들로 구성된다. 모델링된 매니퓰레이터는 기구학 및 동작범위에 대한 속성을 부여되고 외부 입력장치는 space ball을 사용하여 매니퓰레이터의 동작을 구현하였다. 또한 Tele-operation 인터페이스를 사용하여 6축 외부 입력장치와 연계한 시스템을 개발하였으며 외부 입력에 따른 매니퓰레이터의 동작에 대한 동기는 만족할 만한 응답을 보였다. 이는 가상환경에서 작업자 교육을 위한 시스템 개발에 유용할 것이다.

• 대한가정학회지
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• 제20권4호
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• pp.143-153
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• 1982

The objectives of this study were as follows: 1) To describe the group of selected disabled homemakers in terms of demographic and medical variables related to organizational activities in the home and family participation in household activities. 2) To identify those demograhpic and medical variables that were related to organizational activities in the home and family participation in household activities. 3) To identify relationship between organizational activities in the home and family participation in household activities. Questionnaires were given to the selected disabled homemakers living in Seoul. The sample was small(N=35) and it was not random; therefore generalizations could not be made to the population as a whole. Data were analyzed by mean, Kruskal-Wallis one-way analysis of variance by ranks, and Spearman rank correlation coefficients. Homemaker's organizational activities were measured by 16 items about physical and mental activities from Mumaw's Organizational Activities Index. Family participation in household activities was measured by 8 items about how often family members participated in two areas of household activities: house chores and extra-activities. The results were as follows: 1) The homemaker's higher organizational activities scores were associated with younger homemaker, higher the level of education, small households, and higher the economic status. The homemaker without children performed better organizational household activities. The homemaker with shorter the duration of disability performed better organizational activities. The homemaker who needed crutches for mobility performed better organizational household activities. 2) The homemaker who was younger, higher the level of education, with smaller households, and lower the economic level was helped by husband. Husband helped better the homemaker with shorter the duration of disability in household activities. 3) Factors affecting children's participation in disabled homemaker's house chores and extra-activities were the age of homemaker and the marital status. The homemaker was single and older, the children were more helpful. 4) Task standardization score was the highest among the factors of homemaker's organizational activities and families with a disabled homemaker participated more extensively than families with abled homemaker. 5) Significant intercorrelation was found between the dependent variables.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제5권9호
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• pp.1492-1512
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• 2011

Due to multiple hops, mobility and time-varying channel, supporting delay sensitive real-time traffic in wireless local area network-based (WLAN) mesh networks is a challenging task. In particular for real-time traffic subject to medium access control (MAC) layer control overhead, such as preamble, carrier sense waiting time and the random backoff period, the performance of real-time flows will be degraded greatly. In order to support real-time traffic, an efficient adaptive packet scheduling (APS) scheme is proposed, which aims to improve the system performance by guaranteeing inter-class, intra-class service differentiation and adaptively adjusting the packet length. APS classifies incoming packets by the IEEE 802.11e access class and then queued into a suitable buffer queue. APS employs strict priority service discipline for resource allocation among different service classes to achieve inter-class fairness. By estimating the received signal to interference plus noise ratio (SINR) per bit and current link condition, APS is able to calculate the optimized packet length with bi-dimensional markov MAC model to improve system performance. To achieve the fairness of intra-class, APS also takes maximum tolerable packet delay, transmission requests, and average allocation transmission into consideration to allocate transmission opportunity to the corresponding traffic. Detailed simulation results and comparison with IEEE 802.11e enhanced distributed channel access (EDCA) scheme show that the proposed APS scheme is able to effectively provide inter-class and intra-class differentiate services and improve QoS for real-time traffic in terms of throughput, end-to-end delay, packet loss rate and fairness.

• 한국멀티미디어학회논문지
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• 제11권4호
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• pp.504-515
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• 2008

유선 네트워크의 빠른 전송속도 및 다양한 서비스와 무선의 편리성 및 이동성이 결합되어 새로운 서비스 영역을 창출하고 사용자와 서비스 제공자 모두에게 새로운 변화를 가져올 신기술로 유/무선 통합 시대가 전개되고 있다. 유/무선 통합 서비스 중에서 네트워크의 통합은 이기종 네트워크간 연동에 의한 네트워크 융합과 네트워크상에서 전송기술간 융합으로써 매주 중요한 부분을 차지하고 있다. 이러한 상황 속에서 이기종 네트워크의 융합은 서로 다른 네트워크의 융합으로 인해 기존의 보안 기술 및 통신 기술을 그대로 적용하기가 매우 어려우며, 보안 측면에서도 많은 취약점을 내포하고 있다. 기존의 동종 네트워크에서 사용자의 인증 및 키 관리와는 다르게 이기종 네트워크간의 사용자 인증 및 키 관리는 새로운 기술이 필요한 실정이며 또한 동종 네트워크에서 이기종 디바이스간의 보안 기술 확립은 매우 중요한 사항이라 할 수 있다. 본 논문에서는 이기종 네트워크 환경에서의 안전하고 효율적인 키 관리를 제안하여, 이기종 네트워크 디바이스간의 안전한 통신을 제공 할 수 있다.

• 한국의상디자인학회지
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• 제23권3호
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• pp.99-108
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• 2021

The present study examines the overall manufacturing status of local wetsuit makers, problems in the manufacturing process, and future research tasks. The study revealed that most manufacturers use neoprene fabric of varying thickness, depending on the body part. Normally, 3 mm-thick fabric is utilized for high-activity body parts and 5 mm-thick fabric is used for high-activity areas requiring thermal insulation. In terms of the manufacturing method, the tools and manufacturing processes used by companies were found to be similar. However, because of the nature of wetsuits requiring a more complicated manufacturing method than that of general clothing, there were some differences in the manufacturing method processes from company to company, such as bonding and ease treatments. According to wetsuit manufacturers, they make incisions in consideration of the body's curvature and the overall shape and design of the wetsuit when developing patterns. For example, most answered that they preform the wrist and ankle parts, where the body's curvature is obvious. On the question regarding the "difficult manufacturing process", the most frequent response was the "bonding" process. Most manufacturers were found to focus on designs that can improve mobility and clothing fit, and commonly experienced low-order quantity as an operational difficulty. As for the question on the wetsuit-related technology needed in the future, the "development of various designs" was the most frequent answer, followed by the "development of lightweight and diverse materials".

• 한국전자통신학회논문지
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• 제17권3호
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• pp.507-514
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• 2022

가정에서 사람을 보조하기 위해 이동과 작업이 모두 가능한 모바일 매니퓰레이터의 필요성이 커지고 있다. 본 논문에서는 크기가 작고 낮은 가격으로 구성할 수 있는 모바일 매니퓰레이터를 개발하기 위해 모바일 로봇에 탑재할 수 있는 소형 매니퓰레이터 시스템을 개발하였다. 개발한 매니퓰레이터는 4자유도를 가지며, 끝단에 그리퍼와 카메라를 부착하여 물체의 인식과 인식한 물체에 대한 작업 수행이 가능하다. 개발한 매니퓰레이터는 수직 방향의 선형 이동이 가능하여 상대적으로 높이 위치한 사람의 손에 물건을 전달하거나 협업을 수행하는 데 유리하다. 개발한 매니퓰레이터의 4자유도 동작을 위한 4개의 액츄에이터를 매니퓰레이터의 베이스에 가깝게 배치하고 매니퓰레이터의 회전 관성을 줄임으로써 매니퓰레이터의 작업 중 안정성을 높이고 모바일 매니퓰레이터의 전복 위험을 낮추었다. 개발한 매니퓰레이터의 끝단에 위치한 카메라에서 RGB 영상을 획득하고 영상처리를 통해 물체를 인식하여 목표한 위치로 옮기는 픽 앤 플레이스 동작을 시험하였으며 로봇의 작업영역(workspace) 내에서 성공적으로 동작함을 확인하였다.

• 한국컴퓨터정보학회논문지
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• 제28권3호
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• pp.35-43
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• 2023

운전 중 감정 인식은 사고를 예방하기 위해 꼭 필요한 과제이다. 더 나아가 자율 주행 시대에서 자동차는 모빌리티의 주체로 운전자와의 감정적인 소통이 더욱 요구되고 있으며 감정 인식 시장은 점점 확산되고 있다. 이에 따라 본 연구 방안에서는 수집하기 비교적 용이한 데이터인 심리데이터와 행동 데이터를 이용해 운전자의 감정을 분류하는 인공지능 모델을 개발하고자 한다. 오토인코더 모델을 통해 잠재 변수를 추출하고, 이를 본 분류 모델의 변수로 사용하였으며, 이는 성능 향상에 영향을 미침을 확인하였다. 또한 기존 뇌파 데이터를 포함했을 때 보다 본 논문이 제시하는 프레임워크를 사용하였을 때 성능이 향상됨도 확인하였다. 최종적으로 심리 및 개인정보데이터, 행동 데이터만을 통해 운전자의 감정 분류 정확도 81%와 F1-Score 80%를 달성하였다.