• 한국공간구조학회논문집
• /
• 제16권4호
• /
• pp.133-140
• /
• 2016

SLIM AU(A plus U-shaped) composite beam had been developed for not only reducing the story height in residential and commercial building, but also saving the cost of floor construction. The structural performance and economic feasibility was sufficiently approved by means of structural experiments and analytical studies. Even though fire resistance of the SLIM AU composite beam was evaluated throughout furnace fire test, the fire performance of the composite beam using finite element analysis is not analysed yet. Therefore the predictions of fire resistance simulations with loading as well as temperature distribution of the composite beam are summarized in this paper.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2000년도 추계학술대회 논문집
• /
• pp.514-520
• /
• 2000

Numerical simulation is conducted to clarify the heat transfer and fluid flow characteristics of HVAC(Heating, Ventilating and Air-Conditioning) for Mugunghwa passenger car. The HVAC system is installed under the floor of carbody. This new HVAC system has a lot of merits in respect of the center of gravity of carbody, flow induced noise and reduction of condensation water etc. The standard k-epsilon turbulent model and SIMPLEC algorithm based on finite volume method are used to solve the physical HVAC model. To assure convergence, QUICK scheme for momentum equation and the first order upwind scheme for turbulent equations are used. From the results of simulation, the temperature and velocity magnitude are also distributed uniformly in the interior of car.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2000년도 봄 학술발표회 논문집
• /
• pp.587-592
• /
• 2000

As the residential spaces become high-rised and high-density, Multi-story buildings were constructed with transfer girders, Deep beams, wall foundations, floor diaphragms an shear walls which may have column offsets. Especially, In the analysis and design of Multi-story buildings, the lateral loads must be taken into account. But, there have been no appropriate theory and national design code for predicting ultimate shear strength of reinforced concrete Deep beams with web opening. Only empirical and semi-empirical formulas for predicting their ultimate load bearing capacities due to the complexities of the structural non-linearity and material heterogeneity. So this study analyze tow-dimensional finite element model that represents exactly the behavior of real structures with SBETA which are general nonlinear finite element analysis program, and compare the results with that from the real reinforced Concrete Deep beams with web opening tests. From the comparison, and parametric study, The Study presents the elementary data of the earthquake resistance for the reinforced concrete Deep beams with web opening.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
• /
• pp.299-299
• /
• 2000

In this paper, a determination method of number of AGVs fer introducing to the multi-path material handling systems is presented by using genetic algorithm. For serving the raw material to each work stations automatically, there needs to introduce a AGVs for transfer the raw martial. To reduce the overall production cost in the material handling systems, however, a trade off exists between the amount of inventory hold on the shop floor and the number of AGVs needed to provide adequate service. In this paper, firstly a objective function which included the net present fixed costs of each stations and each purchased AGVs, delivering cost. stock inventory cost, and safety stock inventory cost is presented. Secondly by using genetic algorithm, the optimal reorder quantity at each stations is decided, where the number of AGVs is increased step by step. From a simulation with different GA parameters, we can determine a optimal number of AGVs to reduce the overall production cost. Thus, the effectiveness of GA for determining the number of AGVs is verified in automated material handling systems.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2003년도 추계학술대회논문집
• /
• pp.1026-1031
• /
• 2003

A vibration isolation system fur a large reverberation chamber (1,228㎥, 1,000ton) has been installed. The reverberation chamber generates loud noise and induces high level of vibration to perform spacecraft acoustic environmental tests. The isolation system prevents vibration transfer from the chamber to enclosure buildings. This paper describes logical design process and commissioning experiments of the system. Design criteria have been induced from rigid body model of the chamber. Finite element model has been employed to select the characteristics of rubber pads. A total of 21 rubber pads have been installed between the chamber and supporting pedestals. A sand bag of 800kg was dropped on the chamber floor to measure the natural frequency of the isolation system. Absolute transmissibility has been measured while generating 145㏈ in the chamber. The natural frequency of the chamber is 10.5㎐, which is 80% of estimated value. Overall transmissibility at working frequency range (25㎐-10,000㎐) is less than -6㏈.

• 한국전산구조공학회:학술대회논문집
• /
• 한국전산구조공학회 2001년도 가을 학술발표회 논문집
• /
• pp.443-450
• /
• 2001

The Mixed building structures can be divided into three partition, namely, upper wall, lower frame, and transfer system which link two partitions. The purpose of this study is to investigate the nonlinear response characteristics of structures, as the stories of lower frame of mixed building structures changes. The recorded earthquake ground motions of EI Centro 1940 NS is adopted, and the maximum ground accelerations are adjusted to 55ga1, 110ga1, 220ga1, 330ga1. The conclusions of this study are the following. 1) The responses of model that the story of lower frame is one were different from those of other models. 2) The process of ductility hinge occurrence of member was ends of coupling beam of upper wall and ends of beam of lower frame in 55ga1, bases of shear wall on pit floor in 110ga1, and bases of column of 1F in 220ga1.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2003년도 추계학술대회 논문집(III)
• /
• pp.358-362
• /
• 2003

Numerical simulation is conducted to clarify the heat transfer and fluid flow characteristics of HVAC(Heating, Ventilating and Air-Conditioning} for double-deck train. The HVAC system is installed under the roof of carbody. In the lay-out of HVAC system, air duct must be installed to supply air to 1st and 2nd floor respectively. The standard k-epsilon turbulent models and SIMPLEC algorithm based on finite volume method are used to solve the physical HVAC model. To assure convergence, QUICK scheme for momentum equation and the first order upwind scheme for turbulent equations are used. From the results of simulation, the temperature and velocity magnitude are also distributed uniformly in the interior of passenger car.

• 한국가금학회지
• /
• 제7권1호
• /
• pp.13-22
• /
• 1980

On the Chicago Meracntile Exchange, individuals and firms buy and sell contracts for specified amounts of products that are to be delivered at a time period in the future at a price arrived at through openly competitive bidding. The transfer of ownership of these delivery promises takes place in a particular trading pit, for each commodity, on the floor of the Exchange. Trades are officially made by qualified members of the Exchange who act as brokers for their customers. For his services, the broker is paid a nominal round- turn commission fee by the customer. Although each commodity contract carefully describes the particular standards that product must meet in order to be a acceptable for delivery, actually fewer than three percent of the contracts traded are consummated by delivery. For the most part, contract obligations ions art offset, and thereby liquids. before the termination of the delivery month. The trader liquidates his position in the market after analyzing price trends, his timing, and his calculated price objectives. (omitted)

• 한국공간구조학회논문집
• /
• 제19권3호
• /
• pp.77-83
• /
• 2019

AU(A plus U-shaped) composite beam was developed for reducing the story height in the residential buildings, and saving the cosrtuction cost of floor structures. Structural performance and economic feasibility of the composite beam have been sufficiently approved through the structural experiments and the analytical studies. Fire safety for the practical application of the composite beam has also been verified through the fire resistance tests and the heat transfer analyses. In this study 2-points bending tests were performed on the four specimens already tested for fire resistance to evaluate the residual bending strength of AU composite beam after fire accident. The same bending test was performed on the one fresh specimen having the same section and span of the specimens for practically comparative study.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2022년도 봄 학술논문 발표대회
• /
• pp.180-181
• /
• 2022

The higher the addition rate, the less difference in kneading was found. This is because most of the cases are mixed with vinyl gloves by hand when immediately mixed in the field, so there is no problem of mixing dough according to the amount of addition. The mean increase temperature for 20 minutes was 31.6℃ for Plain, 38.1℃ for Al, 33.7℃ for Cu, and 5~7℃ for Al 20% added sample, 38.1℃ for Al 20% added sample, but 36.6℃ for Al 5% added sample. This suggests that it is possible to improve its own heat transferability by adding metal powder to epoxy adhesives.