• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.II
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• pp.480-488
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• 2000

Cabbage is the most important vegetables in korea. The cabbage production was based on arduous human labor. A comprehensive research for substituting the human work by machines has been performed at present. In general, cabbage is cultivated on hillside in korea. The harvested cabbage in a field and carrying it to a vehicle for transportation are very laborious work. Hand labor in cabbage transportation to the market damages the quality of cabbage and is also a cause to increase the cost of cabbage production. This study was to design and evaluate a prototype cabbage loader for deserving efficient and safe transportation of cabbage. The developed cabbage loader was a semi-tracked vehicle operated by a hydraulic system, allowing the safe transporting and the loading of cabbage in a steep field. The maximum loading capacity of the loader was 1.0 ton. By using safety devices attached to the loader, the static slopes were 34.0% and 37.4% for the left and the rear roll-over, respectively. The maximum field speed was about 6km/hr with two cabbage pallets of 750kg at a 25% inclined field. The field capacity was about 35 pallets/hr in case of picking up, carrying and unloading two cabbage pallets. The field efficiency of the loader was analyzed to be more than 8 times in comparison of the conventional human labor. The developed loader would be applied for loading and carrying the other vegetables due to the similarity of operations. The study suggested a standard approach to the design of field machines operated in a steep field.

• Steel and Composite Structures
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• 제4권6호
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• pp.471-487
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• 2004

Modular steel scaffolds are commonly used as supporting scaffolds in building construction, and traditionally, the load carrying capacities of these scaffolds are obtained from limited full-scale tests with little rational design. Structural failure of these scaffolds occurs from time to time due to inadequate design, poor installation and over-loads on sites. In general, multi-storey modular steel scaffolds are very slender structures which exhibit significant non-linear behaviour. Hence, secondary moments due to both $P-{\delta}$ and $P-{\Delta}$ effects should be properly accounted for in the non-linear analyses. Moreover, while the structural behaviour of these scaffolds is known to be very sensitive to the types and the magnitudes of restraints provided from attached members and supports, yet it is always difficult to quantify these restraints in either test or practical conditions. The problem is further complicated due to the presence of initial geometrical imperfections in the scaffolds, including both member out-of-straightness and storey out-of-plumbness, and hence, initial geometrical imperfections should be carefully incorporated. This paper presents an extensive numerical study on three different approaches in analyzing and designing multi-storey modular steel scaffolds, namely, a) Eigenmode Imperfection Approach, b) Notional Load Approach, and c) Critical Load Approach. It should be noted that the three approaches adopt different ways to allow for the non-linear behaviour of the scaffolds in the presence of initial geometrical imperfections. Moreover, their suitability and accuracy in predicting the structural behaviour of modular steel scaffolds are discussed and compared thoroughly. The study aims to develop a simplified and yet reliable design approach for safe prediction on the load carrying capacities of multi-storey modular steel scaffolds, so that engineers can ensure safe and effective use of these scaffolds in building construction.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2005년도 춘계학술발표회
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• pp.155-159
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• 2005

지금까지 국내에서 제작된 요트는 선체의 재질이 FRP로 제작되어 왔으나 FRP는 환경오염 및 해양안전에 관한 법규 규제가 강화되고 있는 현 시점에서는 장래성이 불투명하고 변형 및 파손위험이 높을 뿐만 아니라 선체 제작시 외국의 고가(高價) 목형을 수입해야하는 단점을 안고 있다. 그러나 요트의 선체를 STEEL로 제작함으로써 이러한 문제들을 해결할 수 있다. 강선요트의 구조상 강선재료를 주로 사용함으로서 여러 가지 강도적인 측면에 대한 검토가 필요하며, 소형선박이므로 종강도, 횡강도 부분은 Rule의 허용 응력치에 안전율(Safe Factor)만을 주어서 설계를 하여도 충분히 안정된 구조를 이룰 수가 있다. 그러나, 소형선박에서 가장 문제시 되는 것은 국부강도(Local Strength)의 평가이다. 본 구조해석에서는 선수미에 슬래밍 동적하중과 선수충격에 의한 선수부의 손상 여부와 선수부의 국부강도를 만족 여부를 확인하고, Engine Bed 부분에서의 중량하중과 횡파하중에 대한 검토를 수행하였다.

• 한국산학기술학회논문지
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• 제16권6호
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• pp.4147-4157
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• 2015

전장 환경이 변화함에 따라 무기체계에 다양한 기능이 탑재되고 있다. 이와 함께 무기체계의 이상 유무를 진단하는 무기체계점검장비 또한 이전보다 더 복잡하고 수많은 정보를 다루게 되었다. 하지만, 대부분의 무기체계점검장비는 개발자 중심으로 설계되어있다. 이 때문에, 운용자가 점검장비 디스플레이에 전시되는 정보들을 파악하여 무기체계의 이상 유무를 판단하기 쉽지 않다. 따라서, 점검장비 운용자의 인지부하를 줄이고, 무기체계의 안전한 점검을 수행할 수 있도록 무기체계점검장비 디스플레이를 개발하였다. 이를 위해 생태학적 인터페이스 디자인 기법을 적용하였다. 작업영역분석을 통해 작업영역 모델을 개발하고, 요구정보를 추출하여 무기체계점검장비 디스플레이를 개발하였다. 새로운 디스플레이의 가장 큰 장점은 사용자가 수행하는 점검과 점검장비의 상태를 직관적으로 확인할 수 있다는 것이다. 본 연구 결과로 제시된 디스플레이를 활용하여 운용자가 보다 효율적이고 안전하게 임무를 수행할 수 있을 것으로 기대한다.

• 정보처리학회논문지D
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• 제17D권6호
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• pp.431-442
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• 2010

임베디드 시스템은 하드웨어와 소프트웨어 요소들이 서로 결합된 시스템이기 때문에 설계 시 실시간성(Real-time), 반응성(Reactive), 소규모(Small Size), 경량화(Low Weight), 안전성(Safe), 신뢰성(Reliable), 견고성(Harsh Environment), 저비용(Low Cost) 등의 요소들을 고려하여 설계해야 한다. 그러나 현재 임베디드 시스템 개발에 이러한 요소들을 반영한 설계 기법들이 미비하게 제시되어 있다. 특히 임베디드 시스템 개발에 있어서 프레임워크를 기반으로 임베디드 시스템을 개발하는 형태가 거의 이뤄지고 있지 않다. 이로 인해 현재 개발되어 있는 임베디드 시스템들의 내부 코드들을 살펴보면 시스템 작동과 전혀 상관이 없는 코드들이 무수하게 잔재하고 있으며, 임베디드 시스템 개발에 있어서 재사용성이나 가변성에 대한 고려가 미흡한 실정이다. 따라서 본 연구에서는 임베디드 시스템의 재사용성을 향상시키기 위해 제안했던 재사용 프레임워크 설계에 대한 완전성이나 일관성을 보장하기 위해 Z를 이용하여 프레임워크 설계에 대한 정형 명세 기법을 제시하고자 한다. 또한 Z 언어를 통해 명세한 결과를 Z-Eves Tool을 통해 Z 모델 체킹을 수행하여 프레임워크 설계의 명확성을 보이고자 한다.

• 한국ITS학회 논문지
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• 제21권6호
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• pp.299-310
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• 2022

자율주행시스템은 자율주행 센서, 판단 및 제어 알고리즘 등을 기반으로 스스로 자율주행할 수 있는 기능을 갖추고 있다. 자율주행의 안전성은 도로 네트워크의 운영 상태와 관련성이 높고 도로 인프라와의 협력이 필요하다. 자율주행의 안전한 운행을 위해서는 지속적으로 도로와 교통 조건이 적합한지를 모니터링 할 필요가 있다. 본 연구는 자율주행시스템의 ODD (Operational Design Domain) 특성에 따라 선정된 모니터링 항목을 관리할 수 있는 체계를 구축하기 위한 노드와 링크 체계를 제시하였다. 확장성을 고려하여 기존의 ITS 표준 노드링크 체계를 기반으로 하였으며, 모니터링 대상을 노드와 링크로 표출하는 방안을 제시하였다. 위험도를 5단계로 구분하고 관리하는 방안과 최적경로 탐색 및 통제 시 노드와 링크의 정보를 활용하는 방안을 제시하였다. 세종시를 대상으로 제시된 노드와 링크체계를 기반으로 한 시스템구축 사례를 소개하였다.

• 한국주거학회논문집
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• 제16권3호
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• pp.79-87
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• 2005

The digitalization of our society has brought on the digitalization of housing design and human life. Thus, the concerns for developing digital home have increased. However, most of them has focused on digital technology, not human. This study was intended to examine the residents' housing needs for digital home and to suggest the design guidelines of digital home. The subjects were 400 housewives who lived and used internet in $85m^2$-sized housing unit in the new apartment complex, Busan. The important aspects in digital home design, the residents' needs for digital home design, and the needs for digital system in digital home were examined. The subjects were relatively young in their ages. Also, they had relatively high educational level and middle income. On the base of their housing needs for digital home, the design of digital home like as followings would be desirable: 1) the safe and secure design and digital system, 2) the design to improve residents' health and encourge family interaction, 3) human, warm, and soft interior mood, 4) space composition different from the existing one.

• 한국실내디자인학회논문집
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• 제25권5호
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• pp.63-70
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• 2016

Modern society is suffering from the phenomena of low-fertile, ultra-aging, and low-growth. On this social flow, most social classes undergo vulnerable situation and their overall housing and living condition have difficulties. So far many housing guidelines for diverse population were developed, recently, inclusive 'Customized Housing Design Guideline for Childcare Families' in terms of maintaining family and society has been completed. The purpose of this study is to analyze User Benefit Characteristics of 'Customized Housing Design Guideline for Childcare Families'. The research subjects are essential 140 guidelines appropriate to children's development and parents' care. The research method is contents analysis and the analysis criterion are 4 concepts of the User Benefit Criteria- 'Behavioral Facilitation (BF)', 'Physiological Maintenance (PhM)', 'Perceptual Maintenance (PM)', 'Social Facilitation (SF)'. 3 people inter-raters reliability was established. Altogether, the guidelines were rated in the order of PhM>PM>BF>SF, and these characteristics are similar as common universal design guidelines. This showed the supportability of spatial characteristics in the guidelines related to user's special behaviors. Also, the results show the importance of outdoor space planning for safe social interactions. The supportable characteristics of 'Customized Housing Design Guideline for Childcare Families' could be expected to efficiently apply for new housing development in the future.

• 대한조선학회논문집
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• 제52권6호
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• pp.444-451
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• 2015

Lifting lugs are frequently used in shipyard to transport and turn over blocks of ship and offshore structures. As the shipbuilding technology develops, blocks has become bigger and bigger, and block management technology takes a more important role in shipbuilding to enhance the productivity. For the sake of economic as well as safe design of lug structure, more rational design procedure based on the rigorous structural analysis is needed. This study is concerned with the optimum design of T type lug which is frequently used in shipyard. The optimum thickness of lug's main body is to be determined based on the results of non-linear strength analysis. As far as the present results for the present T type lugs having different capacity are concerned, it seems to be necessary to review the current design procedure of lug structure. The present design procedure can be extensively used in design of various types of lug structures used in shipyard.

• Structural Engineering and Mechanics
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• 제60권5호
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• pp.761-779
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• 2016

Design of safe structures with resistance to progressive collapse is of paramount importance in structural engineering. In this paper, an efficient optimization technique is used for optimal design of steel moment frames subjected to progressive collapse. Seismic design specifications of AISC-LRFD code together with progressive collapse provisions of UFC are considered as the optimization constraints. Linear static, nonlinear static and nonlinear dynamic analysis procedures of alternate path method of UFC are considered in design process. Three design examples are solved and the results are discussed. Results show that frames, which are designed solely considering the AISC-LRFD limitations, cannot resist progressive collapse, in terms of UFC requirements. Moreover, although the linear static analysis procedure needs the least computational cost with compared to the other two procedures, is the most conservative one and results in heaviest frame designs against progressive collapse. By comparing the results of this work with those reported in literature, it is also shown that the optimization technique used in this paper significantly reduces the required computational effort for design. In addition, the effect of the use of connections with high plastic rotational capacity is investigated, whose results show that lighter designs with resistance to progressive collapse can be obtained by using Side Plate connections in steel frames.