• 산업경영시스템학회지
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• 제23권54호
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• pp.137-144
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• 2000

The chloroprene adhesive for ladies' shoe-making applied by the cementing method in KS G 3116 has been evaluated.. For the quality test of adhesive for pump whole cut vamp using chloroprene adhesive, general property and adhesion strength were measured and duration for environmental exposure was tested. Also, a list of experiments for field application was prepared. In case of adhesion-strength measurement,, the KS G 3116 method of peel strength at end of toe was found to be reasonable by measurement through a whole length, toe to heel seat on feather edge.

• 천문학회지
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• 제56권2호
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• pp.187-194
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• 2023

The remote sensing technique of measuring the magnetic field was applied first to sunspots by Hale (1908). Later Babcock (1961) showed that the solar surface magnetic field on a global scale is a dipole in first-order approximation and that this dipole field reverses once every solar cycle. The Wilcox Solar Observatory (WSO) supplies the spherical harmonics coefficients of the solar corona magnetic field of each Carrington Rotation, calculated based on the remotely-sensed photospheric magnetic field of the solar surface. To infer the internal current system producing the global solar coronal magnetic field structure and evolution of the Sun, we calculate the multipole components of the solar magnetic field using the WSO data from 1976 to 2019. The prominent cycle components over the last 4 solar activity cycles are axis-symmetric fields of the dipole and octupole. This implies that the current inversion driving the solar magnetic field reversal originates from the equatorial region and spreads to the whole globe. Thus, a more accurate solar dynamo model must include an explanation of the origin and evolution of such solar internal current dynamics.

• 한국초지학회:학술대회논문집
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• 한국초지조사료학회 2006년도 학술심포지엄 및 제32회 정기총회
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• pp.59-85
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• 2006

• 천문학회지
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• 제19권1호
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• pp.11-14
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• 1986

It is shown in this paper that the astigmatic property of single gravitational lens in static bounded gravitational field can be retained, if n-gravitating body as a whole acts simultaneously as gravitational lens.

• 소성∙가공
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• 제8권4호
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• pp.364-373
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• 1999

For material characterization of semi-solid materials, backward extrusion process, which has been used in forming of hollow-sectioned products, was analyzed by the upper bound analysis in the current study. The existing kinematically admissible velocity field was applied to steady state at which there was no change in the assumed regions of velocity field. For unsteady state, new velocity field, as a function of dead zone angle, was proposed. Through the whole analysis, fiction between die and workpiece was also considered. It has been studied how the process variables, such as friction factor and punch velocity, and material parameters, such as strength coefficient, strain rate sensitivity could affect on analysis results. Finally, by the comparison with the finite element analysis, the reliability and efficiency of the proposed velocity field were discussed.

• International Journal of Korean Welding Society
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• 제5권1호
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• pp.60-65
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• 2005

In the field of welding the mechanical behavior of a welded structure under consideration may be predicted via heat transfer and welding residual stress analysis. Usually such numerical analyses are limited to small regular mesh models or test specimens. Nevertheless, there is very few strength assessment of the whole structure that includes the effect of welded residual stress. The present work is based on the specialized finite element codes for the calculation of nonlinear heat transfer details and residual stress including the external load on the welded RHS (Rectangular Hollow Section) T-joint connections of the whole structure. First the thermal history of the combined fillet and butt-welded T-joint equal width cold-formed RHS are calculated using nonlinear finite element analysis (FEA) considering the quarter model of the joint. Then using this thermal history the residual stress around the joints has been evaluated. To validity the FEA result, the calculated residual stresses were compared with the available experimental results. The residual stress obtained from the quarter model is mapped to the full model and then to the whole structure model using FEM codes. The results from the FEM codes were exported to the commercial package for visualization and further analysis applying loads and boundary conditions on the whole structure. The residual stress redistribution along with the external applied load is examined computationally.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 추계학술대회 논문집
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• pp.274-277
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• 2008

To evaluate high-resolution wind resources for local and coastal area with complex terrain was attemped to combine the prognostic MM5 mesoscale model with CALMET diagnostic modeling this study. Firstly, MM5 was simulated for 1km resolution, nested fine domain, with FDDA using QuikSCAT seawinds data was employed to improve initial meteorological fields. Wind field and other meteorological variables from MM5 with all vertical levels used as initial guess field for CALMET. And 5 surface and 1 radio sonde observation data is performed objective analysis whole domain cells. Initial and boundary condition are given by 3 hourly RDAPS data of KMA in prognostic MM5 simulation. Geophysical data was used high-resolution terrain elevation and land cover(30 seconds) data from USGS with MM5 simulation. On the other hand SRTM 90m resolution and EGIS 30m landuse was adopted for CALMET diagnostic simulation. The simulation was performed on whole year for 2007. Vertical wind field a hour from CALMET and latest results of MM5 simulation was comparison with wind profiler(KEOP-2007 campaign) data at HAENAM site.

• 한국초전도ㆍ저온공학회논문지
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• 제25권4호
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• pp.75-80
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• 2023

Rare earth barium copper oxide (REBCO) materials have shown the possibility of high-temperature superconductor (HTS) magnetic resonance imaging (MRI) magnets due to their elevated transition temperature. While numerous MRI magnet designs have emerged, there is a growing emphasis on estimating the cost before manufacturing. In this paper, we propose two designs of REBCO whole-body MRI magnets: (1) 1.5 T and (2) 3.0 T, the standard center field choices for hospital use, and compare their costs based on conductor usage. The basis topology of the design method is based on discretized solenoids to enhance field homogeneity. Magnetic stress calculation is done to further prove the mechanical feasibility of their construction. Multi-width winding technique and outer notch structure are used to improve critical current characteristic. We apply consistent constraints for current margins, sizes, and field homogeneities to ensure an equal cost comparison. A graph is plotted to show the cost increase with magnetic flux growth. Additionally, we compare our designs to two additional MRI magnet designs from other publications with respect to the cost and magnetic flux, and present the linear relationship between them.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2000년도 춘계학술대회
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• pp.9-26
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• 2000

Eventually so as to realize the construction safety, 1 found out the cause of accident and specificities of the construction industry. This study presented to several situations and problems on construction safety. As a result of this study, the below matters must be improved for more effective the construction safety management system. 1. It need to introduce the total construction safety management system. Because there is not effectiveness in the current safety management to the first on the construction field. a. We must consider the safety in the whole parts of the process of the construction and constructors of each part must devide responsibility of the construction safety as a CDM(The Construction Designed Management) used in UK. b. It is desirable to proceed control of safety in the whole parts of the construction to introduce the total safety coordinator that can consult the matters of safety as a law accepted in EU. c. Like management of the construction safety in USA, direction of the construction safety must be made to work exactly by code or manual. d. To improve the organization of the construction safety on the construction field unefficient, it must be introduced safety supervisor, safety coordinator or institutionalization of safety consultant. 2. The law of the construction safety not only have wasteful element but also decrease efficiency by overlapping of regulation, The Ministry of Labour and The Ministry of Construction & Transportation, So laws related with safety must be instituted. a. To realize total safety management, The Ministry of Labour must legislate the basic law about safety management in whole field. b. To legislate the construction safety under one law, and improve efficiency of the overlapping of regulation and the similar law by The Ministry of Construction & Transportation. c. It must be made the law of construction safety that can proper to change of situation in construction. d. The standard of safety must be instituted belong to international level and improved by year. e. We must improve irrational regulation to realize activity of safety self regulating for progress competition in construction industry

• Wind and Structures
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• 제20권2호
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• pp.249-274
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• 2015

Long-span cable-stayed bridges exhibit some features which are more critical than typical long span bridges such as geometric and aerodynamic nonlinearities, higher probability of the presence of multiple vehicles on the bridge, and more significant influence of wind loads acting on the ultra high pylon and super long cables. A three-dimensional nonlinear fully-coupled analytical model is developed in this study to improve the dynamic performance prediction of long cable-stayed bridges under combined traffic and wind loads. The modified spectral representation method is introduced to simulate the fluctuating wind field of all the components of the whole bridge simultaneously with high accuracy and efficiency. Then, the aerostatic and aerodynamic wind forces acting on the whole bridge including the bridge deck, pylon, cables and even piers are all derived. The cellular automation method is applied to simulate the stochastic traffic flow which can reflect the real traffic properties on the long span bridge such as lane changing, acceleration, or deceleration. The dynamic interaction between vehicles and the bridge depends on both the geometrical and mechanical relationships between the wheels of vehicles and the contact points on the bridge deck. Nonlinear properties such as geometric nonlinearity and aerodynamic nonlinearity are fully considered. The equations of motion of the coupled wind-traffic-bridge system are derived and solved with a nonlinear separate iteration method which can considerably improve the calculation efficiency. A long cable-stayed bridge, Sutong Bridge across the Yangze River in China, is selected as a numerical example to demonstrate the dynamic interaction of the coupled system. The influences of the whole bridge wind field as well as the geometric and aerodynamic nonlinearities on the responses of the wind-traffic-bridge system are discussed.