• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2000년도 춘계공동학술대회 논문집
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• pp.253-256
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• 2000

In general, Automated Storage/Retrieval Systems (AS/RS ) have racks of equal sized cells to utilize the concept of unit-load. Most of the techniques for the performance estimation of a unit-load AS/RS are a static model or computer simulation. Especially, their models were developed under assumption that the Storage/Retrieval (S/R) machine performs only single command (SC) or dual command (DC). In reality, defending on the operating policy and the status of the system at a particular time, the S/B machine performs a SC or a DC, or becomes .: idle. In order to resolve these weak points, we propose a stochastic model for the performance estimation of unit-load AS/RS by using a single-server queueing model. Expected numbers of waiting storage and retrieval commands are found

• 한국농공학회:학술대회논문집
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• 한국농공학회 2001년도 학술발표회 발표논문집
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• pp.492-496
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• 2001

The purpose of this study is to estimation of pollutants loads using unit load method in Hong-bo watershed. In general, because river water quality management have been conducted with point source pollutant in our country, pollutants caused by precipitation have not been managed well so far. Especially the pollutants tends to concentrate in the reservoir of reclaimed land. Therefore, the reservoir of reclaimed land is need to continuous monitoring and update of an accurate data. also, It is need to improvement of environmental pollution. There are divide into nine sub-catchments and made an estimate of pollutants loads using unit load method in Hong-bo basin. The sample of data was during the 10 years.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.740-743
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• 2001

Sandwich structure is widely used in various fields of industry due to its excellent strength and stiffness compared with weight. We studied the sandwich structure which has honeycomb core type. We are concerned about its buckling and bending stress with respect to its side length, thickness and the height ratio of its unit core. After obtaining the buckling critical load of unit core, we applied it to the sandwich structure to observe the bending behavior. When we compared the buckling with bending stress under buckling critical load, we observed that models of which length ratio of unit honeycomb core, A, is lower than 0.04 and the thickness of core, t, is thicker than 0.09 mm, is subjected to the ultimate stress by bending before buckling.

• 한국해양공학회지
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• 제16권6호
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• pp.55-59
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• 2002

Delamination means that cracking occurs on the interface layer between composite laminates. In this paper, to predict the delamination growth in composite laminates subjected to low-velocity impact, the unit load method was introduced, and an eighteen-node 3-D finite element analysis, based on assumed strain mixed formulation, was conducted. Strain energy release rate, necessary to determine the delamination growth, was calculated by using the virtual crack closure technique. The unit load method saves the computation time more than the re-meshing method. The virtual crack closure technique enables the strain energy release rate to be easily calculated, because information of the singular stress field near the crack tip is not required. Hence, the delamination growth in composite laminates that are subjected to low-velocity impact can be efficiently predicted using the above-mentioned methods.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.211-215
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• 2004

This paper describes the result of structure analysis and load test of torque arm for driving gear unit. The purpose of the analysis and test is to evaluate an safety which torque arm shall be considered fully sufficient rigidity so as to satisfy proper system function under maximum load. Driving gear unit consist of gearbox and torque arm. Both components, torque arm is significant component subjected to the vehicle and motor loads. The evaluation methode is used the FEM analysis, static and fatigue test. The test results have been very safety and stable for design load conditions.

• 한국해양공학회지
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• 제14권1호
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• pp.67-73
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• 2000

The dynamic behavior of a moving elastic body system with three constant velocitics on a simple beam with an axial load is analyzed by numerical method. A moving elastic body system is composed of an elastic body and a suspension unit with two unsprung masses. The governing equations are derived with an aid of Lagrange's equation. These equation are solved by Runge-Kutta method. The damping coefficients a spring constants of the suspension unit the force circular frequency on a moving elastic body the velocity of a moving elastic body system. These effects are more important in the high modes of a simple beam.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 B
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• pp.479-481
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• 1995

A Typical load pattern has been an important role in operation and cogeneration planning of unit building. In this paper, The self-organising feature maps have been applied to indentify the day type of unit building using measured load data. Also correlation coefficient method was used for this. These results are presented.

• Journal of applied mathematics & informatics
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• 제23권1_2호
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• pp.505-516
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• 2007

In this paper, we provide some fundamental properties and basic theoretical results of K-class-based dedicated storage policy in a unit load system assuming the constant-space assumption that the number of storage locations for a class is not the maximum aggregate inventory position for a class but the sum of space requirement for products assigned to the class. The main theorem is that there exists a (K+1) -class-based storage layout whose expexted single command (SC) travel time is not greater than that of a K-class-based storage layout, i.e, $E(SC^*_{K+1}){\leq}E(SC^*_K)\;for\;K=1,{\cdots}$, (n-1).

• 전력전자학회:학술대회논문집
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• 전력전자학회 2017년도 전력전자학술대회
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• pp.198-199
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• 2017

This paper proposed a new control method for supercapacitor (SC) to compensate the pulse load transient and enhance the power quality of dc microgrid. By coordinating the operation frequency, the supercapacitor is controlled to handle the surge current component while the low-frequency current component is dealt with by remaining sources in the system. Based on the state of charge and dc bus voltage level, the SC unit operation mode is automatically decided. Meanwhile, the dc bus voltage level indicates the power demand of the whole system; by regulating the dc bus voltage, the mismatch of power demand is covered by SC unit. The effectiveness of proposed method is verified by experiment prototype formed by two distributed generation and one supercapacitor unit.

• 한국태양에너지학회 논문집
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• 제31권4호
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• pp.34-40
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• 2011

Apartment Housing has been increasing steadily, particularly our current super high-rise apartment houses that represent the culture has become a trend in Korea. These super high-rise apartment houses' curtain wall system increases heating and cooling loads, it is expected to vary by each unit's thermal properties. In this study, measured indoor environment and energy simulation results were compared to actual energy consumption. As a result, the various factors that affect heating and cooling loads, such as direction, plan type and glazing area, influence each unit's load characteristic. In particular, according to the electricity costs savings behavior, the occupant's thermal discomfort is expected to be large in summer. Therefore, to reduce heating and cooling load for each unit requires a reasonable plan.