• 한국지능시스템학회논문지
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• 제17권3호
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• pp.390-396
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• 2007

Fuzzy-CBR Collision Avoidance Support System is a system that finds a solution from past knowledge retrieved from the database and adapted to a new situation. Its algorithm has resulted to an adapting a solution for a new situation. However, ontology is needed in identifying concepts, relations and instances that are involved in a situation in order to improve and facilitate the efficient retrieval of similar cases from the CBR database. This paper proposes the way to apply ontology for identifying the concepts involved in a new environment and use them as inputs, for a ship collision avoidance support system., Similarity will be obtained through document articulation and using abstraction levels. A conceptual model of a maneuvering situation will be built using these ontologies.

• 대한교통학회지
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• 제11권3호
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• pp.49-66
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• 1993

The successful management of logistics in an organization requires the careful coordination and manipulation of both movement and storage. In this study, we can show what is the most efficient and the cheapest method to transport the petroleum products under a few constraints with the model of linear programming. And also, the model can give some important informations so as what is the best coverages of each terminals by types, how many products should be exchanged among each companies and which terminals or complexes are economically prior to the others. Even we can understand that the duality is one of the useful measures to evaluate the economical efficiencies of transportation and storage related elements such as complex and terminal location, transport mode, storage tankage capacity and in/outflow facilities of terminals etc.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2016년도 추계학술대회
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• pp.489-492
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• 2016

Transportation in the logistics, many business organizations are engaged in monitoring and tracking the vehicles in order to improve logistics services, reduce expenses and secure security in cargo transportation. It is saving time and money by tracking and monitoring vehicles which transport cargo in supply chain of logistics. Therefore the main issue of delivery flow is to improve services, and ensure the safety in transportation system. This article suggests the tracking and monitoring model to keep safety transports on ICT network. It focuses on precise delivery control by monitoring and tracking vehicles to save time and costs. The status of product movement is analyzed for proper decision making. The vehicle embedded with RFID is automatically tracked in the movement process by tracking and monitoring model. The main role keeps safety tracking to reduce costs and to deliver products at proper time and location.

• 한국ITS학회 논문지
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• 제15권3호
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• pp.23-33
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• 2016

본 연구는 SUR모형을 활용하여 서울 거주자의 수단별 통행시간 비율에 대한 영향요인을 규명하였다. 영향요인은 가구원 및 가구의 특성, 존 특성 변수 등을 선정하였다. 통행수단은 기존의 18개 유형을 압축하여 도보, 개인통행수단, 버스, 지하철, 철도, 자전거 등 6개 수단으로 재 정의하였다. 분석 결과, 개인교통수단과 대중교통간의 뚜렷한 차이를 발견하였다. 우선 차량을 보유하고 운전면허가 있는 경우에는 개인통행수단을 이용하는 경향이 강한 것으로 나타났다. 이와 함께 대표적인 대중교통 수단인 버스와 지하철간의 상관관계를 파악할 수 있었다. 지하철 수단은 개인통행수단이 이용 가능한 통행자가 함께 이용하는 패턴을 보인 반면, 버스 수단은 개인통행수단 이용이 어려운 경우에 이용하는 경향을 보였다. 이러한 선호도는 향후 서울을 포함한 수도권의 대중교통 정책을 수립함에 있어 다양한 시사점을 제시할 수 있을 것으로 기대한다.

• Wind and Structures
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• 제27권4호
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• pp.255-267
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• 2018

This paper investigated the wind-snow flow around the bogie region of a high-speed train under crosswinds using a coupled numerical method of the unsteady Realizable $k-{\varepsilon}$ turbulence model and discrete phase model (DPM). The flow features around the bogie region were discussed and the influence of bogie fairing height on the snow accumulation on the bogie was also analyzed. Here the high-speed train was running at a speed of 200 km/h in a natural environment with the crosswind speed of 15 m/s. The mesh resolution and methodology for CFD analysis were validated against wind tunnel experiments. The results show that large negative pressure occurs locally on the bottom of wheels, electric motors, gear covers, while the positive pressure occurs locally on those windward surfaces. The airflow travels through the complex bogie and flows towards the rear bogie plate, causing a backflow in the upper space of the bogie region. The snow particles mainly accumulate on the wheels, electric motors, windward sides of gear covers, side fairings and back plate of the bogie. Longer side fairings increase the snow accumulation on the bogie, especially on the back plate, side fairings and brake clamps. However, the fairing height shows little impact on snow accumulation on the upper region of the bogie. Compared to short side fairings, a full length side fairing model contributes to more than two times of snow accumulation on the brake clamps, and more than 20% on the whole bogie.

• 대한교통학회지
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• 제32권2호
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• pp.152-161
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• 2014

현재 KHCM이 출판될 당시와 현재의 대중교통 환경이 달라져 승하차시간 산정방법이 달라질 필요가 있다고 판단된다. 이에 본 연구에서는 승하차시간에 영향을 주는 승하차수, 입석자수, 상면지상고를 변수로 총승하차시간값을 도출하는 모형을 다중회귀모형을 통해 분석하였다. 그 결과 총승차시간의 경우는 승하차수, 입석자수, 상면지상고 순으로 영향력의 차이가 있었으며, 총하차시간의 경우는 하차자수, 상면지상고 순으로 분석되었고, 두 개의 모형에서의 독립변수들은 모두 종속변수와 양의 상관관계를 가지는 것으로 나타났다. 모형을 통해 예측된 순수 승하차시간은 기존의 버스정류장은 물론 TOD를 고려한 신도시 등의 신설 버스정류장 용량 산정에 유용할 것으로 판단된다.

• 한국방재학회 논문집
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• 제10권2호
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• pp.55-60
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• 2010

본 연구는 한국의 54개 중소도시를 대상으로 압축도시 이론에서 주장하는 고밀개발, 혼합적인 토지이용과 같은 계획 요소들이 실제 대중교통을 이용한 통근 통행에 영향을 미치는지 실증적으로 분석하였다. 분석 결과 토지이용 변수들 중에서는 인구밀도와 직주균형비가 높을수록 대중교통 통근률이 높아지는 것으로 나타난다. 이와 같은 결과는 압축도시 계획 이론에서 주장하는 바와 같이 밀도 수준이 높아질 경우 대중교통 서비스를 유지하는데 있어 유리하고 또한 토지를 복합적으로 이용함으로써 직장을 포함한 다양한 활동들에 대한 접근성이 높아지기 때문에 자동차 이용이 줄어들고 대중교통 이용이 많아지는 것으로 판단된다. 따라서 대중교통을 이용한 통근 통행을 활성화하기 위해서는 고밀개발과 함께 직주균형과 같은 복합적인 토지이용을 유도하는 도시 정책이 요구된다. 또한 교통서비스 시설들 중에서는 도로 밀도와 지하철 유무가 대중교통 통근률에 영향을 미치는 요인으로 나타나는데, 이는 대중교통 이용률을 높이기 위해서는 먼저 효율적인 대중교통 서비스의 확충이 전제되어야 함을 보여준다. 따라서 대중교통 통근률을 높이기 위해서는 고밀 복합적인 토지이용 정책의 추진과 함께 지하철과 같은 대중교통 서비스시설에 대한 투자가 함께 이루어져야 한다.

• Steel and Composite Structures
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• 제25권1호
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• pp.117-126
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• 2017

The component method is an analytical approach for investigating the moment-rotation relationship of steel connections. In this study, the component method was improved from two aspects: (i) load analysis of mechanical model; and (ii) combination of spring elements. An optimized component method with more reasonable component models, spring arrangement position, and boundary conditions was developed using finite element analysis. An experimental testing program in two major-axis and two minor-axis connections under symmetrically loading was carried out to verify this method. The initial rotational stiffness obtained from the optimized component method was consistent with the experimental results. It can be concluded that (i) The coupling stiffness between column and beam flanges significantly affects the effective height of the tensile-column web. (ii) The mechanical properties of the bending components were obtained using an equivalent t-stub model considering the bending capacity of bolts. (iii) Using the optimized mechanical components, the initial rotational stiffness was accurately calculated using the spring system. (iv) The characteristics of moment-rotation relationship for beam to column connections were effectively expressed by the SPRING element analysis model using ABAQUS. The calculations are simpler, and the results are accurate.

• International Journal of Naval Architecture and Ocean Engineering
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• 제10권3호
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• pp.318-328
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• 2018

Disk type underwater gliders are a new type of underwater gliders and they could glide in various directions by adjusting the internal structures, making a turnaround like conventional gliders unnecessary. This characteristic of disk type underwater gliders makes them have great potential application in virtual mooring. Considering dynamic models of conventional underwater gliders could not adequately satisfy the motion characteristic of disk type underwater gliders, a nonlinear dynamic model for the motion simulation of disk type underwater glider is developed in this paper. In the model, the effect of internal masses movement is taken into consideration and a viscous hydrodynamic calculation method satisfying the motion characteristic of disk type underwater gliders is proposed. Through simulating typical motions of a disk type underwater glider, the feasibility of the dynamic model is validated and the disk type underwater glider shows good maneuverability.

• 한국건축시공학회지
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• 제12권6호
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• pp.648-663
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• 2012

With recent attempts to improve quality and productivity, the prefabrication manufacturing system has been occupying an increasing share of the construction area. To minimize site work, material is more frequently being produced and partially assembled at a plant, and then installed at a site. For this reason, the production process is being divided and the materials are being delivered to the site after passing through multiple plants. With these changes in the production process, the materials delivery plan is becoming an important management point. In particular, as road transportation using trucks has a 71 percent share of the domestic transportation market, selecting the proper transportation path is important when delivering materials and equipment to a site. But the management system at the project design phase to calculate the delivery cost by considering the production process of the pre-fab material and the $CO_2$ emission at the material delivery phase is currently lacking. This study suggests a process design model for assembly production of the pre-fab material and transportation logistics based on carbon emission. The suggested model can be helpful to optimize the location of the intermediate plant. It is expected to be utilized as a basic model at the project plan and design phase when subcontractors make decisions on items such as materials procurement, selecting the production method, and choosing the location of the assembly plant.