• Magazine of the Korea Concrete Institute
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• v.8 no.2
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• pp.151-161
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• 1996

This paper presents a series of tests to produce the h~gh quality concrete to be filled Inside the steel tube columns. Thls concrete filled steel tube system requires not only the high strength, but a150 the flowable concrete. Laboratory test has been performed to clarlfy the material characteristics and to produce the optlmal mix design proportion. Full scale site mock up test has been then carried out to slnlulate the actual construct~on conditions including the product~on of concrete at the rermcon batch plant, transportation to the construction site, proper workabil~ ty and man power required , 4ddit1onal mock up test has finally been performec to irivesti gate any unfavorable construction s~tuatioils since the actual concrete placement has been sched uled in cold weather period, so that the high quality concrete construction is convinced to be successfully carried out.

• Transactions of the Korean Society of Automotive Engineers
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• v.25 no.1
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• pp.35-41
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• 2017

The use of engineering plastics in automotive components is increasing with the trend towards improving the car strength and reducing weight. Among the different choices of materials, engineering plastic emerged as the necessary material for achieving lower costs, reduced weight and improved production efficiency. To produce the automotive parts, it is important to predict defect and validation of injection molding prior to design. Injection molding analysis and structural analysis are widely applied as a part of the design process when developing automotive parts. Injection molding analysis, in particular, involves a highly complicated mechanism that requires deep knowledge of polymer properties as well as an analytic approach different from that used for a general isotropic material when the molded material is used as a structural material. This is because the parts made of polymer have pre-stress factors such as intrinsic deformation and residual stress. The most important factors for injection molded plastic products are injection molding condition and cavity design, taking into account ease of molding, mass production and application. Despite optimal injection molding conditions and cavity design, however, glass fiber orientation is critically linked to strength reduction. The application of injection molding and structural coupled analysis provides a low-cost solution for product molding and structural validation, all prior to the actual molding. The purpose of this study involves the validation, pre-study, and solution of defect in injection-molded polymer automotive parts using the simulation software for injection molding and structural coupled analysis. Finally, this thesis provides validation of an injection molding and structural coupled analytic mechanism that can demonstrate the effect of glass fiber orientation on mechanical strength. Design improvement ideas for the injection molded product of PPS (Poly Phenylene Sulfide)+40% glass fiber are also suggested.

• Journal of the Society of Naval Architects of Korea
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• v.46 no.1
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• pp.78-86
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• 2009

A capacity calculation and process analysis is a very important part for the entire ship production planning. Ship's production plan is set up with a concept that the product is produced based on the capacity achievable by the processes while general manufacturing sets up the production plan based on product lead-time. Therefore, in case the calculation of capacity for each process of shipbuilding yard is different from actual conditions, a series of production plan - ship table composition, dual schedule plan and execution schedule plan, etc - may accumulate errors, lose reliability of planning information and cause heavy cost deficit in this course. In particular, in case of new shipbuilding yard, stocks between processes are built up and half blocks are not supplied in timely manner, and that is sometimes due to the clumsiness of the operator but it is more often because of the capacity to execute each process is not logically calculated. Therefore, this paper presents the process to calculate the assembly leadtime and assembly process capacity for shipbuilding yard assembly factory. This paper calculated the block type for calculation of assembly lead time based on block DAP(detailed assembly procedure), and introduced cases that calculate production capacities by assembly surface plate by considering the surface plate occupied area of the blocks that change depending on assembly field area and assembly processes through assembly simulation.

• Korean Journal of Oriental Medicine
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• v.12 no.1
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• pp.13-22
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• 2006

Background and Aims: Herbal drugs and traditional medicines have lately attracted considerable attention by global pharmaceutical corporations because the conventional chemical drugs didn't work well for many chronic diseases or intractable diseases. The government of Korea is also supporting to develop the new drug which is high value added product, and the natural medicine including herbal medicine(or Traditional Korean Medicine) have a significant presence in this field. non-clinical pharmacology/toxicology study and clinical trial are the two major criteria which estimate efficacy and safety for registration of new drugs. All of the pharmaceutical companies producing herbal medicine and the academic and the academic world of Tradition Korean Medicine have the will to develop new herbal drugs, but there are obstacles that they have neither experience nor guideline about clinical trial. Therefore for developing new herbal drugs, it is necessary to research the present conditions and comprehensive systems about clinical trial in Northeast Asian countries China, Taiwan and Japan because they have the common background with Korea in traditional medicine fields. Methods : The present state of clinical trial for herbal medicine in Korea was investigated. And then, those in China, Taiwan, Japan was also investigated. Results and conclusions : There are significant differences among 4 Southeast Asian countries Korea, China, Taiwan and Japan each in present condition, purpose, involved comprehensive system including legislation, and actual operation of clinical trial for traditional medicine.

• Journal of the Korea Convergence Society
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• v.12 no.12
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• pp.83-91
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• 2021

For agricultural products, supply is irregular due to changes in meteorological conditions, and it has high price elasticity. For example, if the supply decreases by 10%, the price increases by 50%. Due to these fluctuations in the prices of agricultural products, the Korean government guarantees the safety of prices to producers through small merchants' auctions. However, when prices plummet due to overproduction, protection measures for producers are insufficient. Therefore, in this paper, we designed a business model that can be used in the electronic transaction system by predicting the price of agricultural products with an artificial intelligence algorithm. To this end, the trained model with the training pattern pairs and a predictive model was designed by applying ARIMA, SARIMA, RNN, and CNN. Finally, the agricultural product forecast price data was classified into short-term forecast and medium-term forecast and verified. As a result of verification, based on 2018 data, the actual price and predicted price showed an accuracy of 91.08%.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.7
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• pp.819-825
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• 2014

The diurnal range of temperature in korea is increasing. We know that the environment has deteriorated through report about railway damage and economic loss caused by climate. In these conditions, Monitoring device for railway must operate to support the operations and maintenance. Therefore, In this paper, COM-based monitoring device implemented using Industrial-Extended electronic components and made, We tested compliance about temperature environment of actual railway. We verified through testing about cold and dry heat of monitoring device. Used components in this product will be able to utilize the development of the railway industry of electronics.

• Journal of the Korean Society of Clothing and Textiles
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• v.35 no.8
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• pp.906-917
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• 2011

This study identified the present state of store and selection criteria of supplier from the regional fashion buyer point of view and examined the effects of the factors of relative impact between buyer and supplier on the relational bond. The interviews and questionnaires were administered to the owners or the sellers of 85 fashion retail stores in Gwangju. For analysis of data, frequency, means, factor analysis, Cronbach's ${\alpha}$ and regression analysis were applied. The results were as follows. First, in the results of examining the actual conditions of store managers for fashion buyers, fashion buyers complained about lengthy travelling and time consumption inconvenience. They also reported decrease in margin and monthly mean sales over last year. Second, the most important selection the criteria for the supplier were product power, followed by a convenient store layout. Finally, higher quality communication, more compromises, and higher dependence were affected with higher satisfaction, trust, and commitment in suppliers; conversely, the trust and commitment of the buyers decreased relative to the increased power of the suppliers.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.9
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• pp.2901-2907
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• 1996

Flatness of cold rolled strip is vital to the quality of the product and productivity of the mill. Therefore, in recent year requirement for flatness control in strip rolling have become increasingly severe. The necessity for more accurate automatic gauge control and automatic flatness control(AFC) has increased by customer's requirement for cold rolled steel sheets with thinner gauge and better flatness quality. In this paper, the performance and functions of AFC system installed on the 4 hi-reversing mill has been investigated under actual conditions. The test results are as follows : The more strip thickness is thick, the smaller the I-value. The I-value is a strain measured by stressometer. Complex distributions of strip tension are controlled to remove not only a quarter buckle but also a simple center wave and edge wave. The defects caused by poor flatness have been drastically decreased. And a proper coolant temperature for work roll cooling system on the AFC system is about $50~55^{\circ}C$.

• Journal of the Korea Safety Management & Science
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• v.10 no.4
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• pp.229-240
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• 2008

With the effectuation of Kyoto Protocol, one of the important movement throughout the world is reducing the emission of greenhouse gas which is the main reason of making global warming. The actual factor of greenhouse gas is CO2, and in year of 2002 20% of total CO2 emission was produced only through transportation throughout the South Korea. In the contrary, the recycling of municipal wastes in South Korea was 44.0% in 2002, but it will be targeted upto 53.5% in 2011. All of these show environment-conscious logistics should be implemented together throughout the each stage of distribution with the development of product and service. This study applied survey research for the activities affecting to the emission of CO2 and packaging wastes produced from transportation and packaging stages in logistics area. For this, survey questionary was constructed with five specific areas - strategy, transportation & distribution, custody, packaging, and information. Based on the 148 returned survey questionaries, this study analyzed 52 categories and finally suggests necessary modal shift, collaboration & co-operation in logistics, LCA(life-cycle assessment), and other promoting policies for the environment-conscious logistics in effective way.

• Journal of the Korean Society of Propulsion Engineers
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• v.22 no.5
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• pp.81-87
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• 2018

In hypersonic aircraft, increase of aerodynamic and engine heat lead thermal load in airframe. It could lead structural change of aircraft's component and malfunctioning. Endothermic fuels are liquid hydrocarbon fuels which absorb the heat load by undergoing endothermic reactions. In this study, we investigated the relationship between product, coke formation and catalytic properites of endothermic catalysts by using exo-tetrahydrodicyclopentadiene as a fuel in a fixed bed flow reactor similar to the actual reaction conditions.