• Computers and Concrete
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• v.6 no.3
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• pp.253-268
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• 2009

This study aims to develop a cost-based high-performance concrete (HPC) mix optimization system based on an integrated approach using artificial neural networks (ANNs) and genetic algorithms (GA). ANNs are used to predict the three main properties of HPC, namely workability, strength and durability, which are used to evaluate fitness and constraint violations in the GA process. Multilayer back-propagation neural networks are trained using the results obtained from experiments and previous research. The correlation between concrete components and its properties is established. GA is employed to arrive at an optimal mix proportion of HPC by minimizing its total cost. A system prototype, called High Performance Concrete Mix-Design System using Genetic Algorithm and Neural Networks (HPCGANN), was developed in MATLAB. The architecture of the proposed system consists of three main parts: 1) User interface; 2) ANNs prediction models software; and 3) GA engine software. The validation of the proposed system is carried out by comparing the results obtained from the system with the trial batches. The results indicate that the proposed system can be used to enable the design of HPC mix which corresponds to its required performance. Furthermore, the proposed system takes into account the influence of the fluctuating unit price of materials in order to achieve the lowest cost of concrete, which cannot be easily obtained by traditional methods or trial-and-error techniques.

• The Journal of Fisheries Business Administration
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• v.41 no.2
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• pp.153-174
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• 2010

This study is aimed to analyze the establishing of fisheries management consulting system by case study of similar organizations. For a gradual extension of new technology of fisheries, National Fisheries Research and Development Institute(NFRDI) has launched fisheries consulting project including management in 2010. Fisheries management consulting needs practical and theoretical background regarding its standardization of process, systematization. To achieve this, fisheries management consulting system has to follow farm management consulting system by means of benchmarking. In order to analyze farm management consulting system, I investigated its role organizations(MIFAFF, RDA, KFRI), farm consulting guide. And also, it was conducted to investigated establishing of fisheries management consulting system through development of standard management consulting table and consulting indicators. The research results showed that the realm of fisheries management consulting should be redefined and systematized apposite to the case of fisheries actual conditions. In recent years, to enhance improvement of the fisheries income, there is need to be focused on the efficient utilization of fisheries management consulting system. It is expected that fisheries management consulting system be main issue in fisheries industry.

• Journal of the Society of Disaster Information
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• v.14 no.1
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• pp.28-35
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• 2018

The following research has focused and implemented on designing a system that classifies the severity of mass casualty situations across both normal and disaster levels. The system's algorithm has implemented requirements such as accuracy as well as user convenience. The developed e-Triage System has applied various severity classification algorithms implemented from IoT concepts. In order to overcome flaws of currently used severity classification systems, the e-Triage System used electronic elements including the NFC module. By using the mobile application's severity classification algorithm the system demonstrated quick and accurate assessment of patient. Four different LED lamps visualized the severity classification results and RTS scores were portrayed through FND(Flexible Numeric Display) after a two wave classification.

• IE interfaces
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• v.21 no.1
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• pp.51-64
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• 2008

As apparel manufacturers have increased their outsourcing garment making to cope with the rapid changing market, the information sharing has been the most important factor for the Korean apparel industry. The purpose of this research was to identify the properties and effects of information sharing system between Korean apparel manufactures and contractors. For this study, two apparel manufactures which actually used the information sharing systems were case-studied for the properties and effects of the information sharing system. The results of this study are shown as follows; 1) The companies ("J" and "S"), studied in this paper used sharing information mostly on order, delivery, and accounts within their contractors based on information sharing system. Company "J" turned out to have strong partnership with their contractors and developed more flexible manufacturing system and QR strategy. They shared not only basic transaction information but also quality inspection information and work-in-process information by using information sharing system. 2) The effects of information sharing system were proved as business transaction time reduced more than 60 percent, compared when staffs had to face to face, or use phone or fax to deliver documents. This study was investigated to provide an example which introduces information sharing system objectively and systematically to the apparel industry.

• Journal of Ocean Engineering and Technology
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• v.23 no.2
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• pp.104-109
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• 2009

In the view of the importance of material reduction due to the jump in oil and steel prices, an optimized structural system for lifting lugs was developed. Such a system is needed hundreds of thousands of times a year. A direct design process was added to this developed optimized system to increase the design efficiency and provide a way of directly inserting a designer's decisions into the design system process. In order to verify the system efficiency and convenience, several new prototype lug shapes were suggested using the developed system. From these research results, it was found that the slope of the main plate of the lug structure has a tendency to move from about 45 degrees to about 60 degrees and the design weight was reduced from an initial value of about 32kgf to about $15{\sim}19kg_f$ after the redesign. Based on these initial research results, an efficient reduction in steel weight was expected considering the enormous consumption of lug structures per year. Additionally, a more detail structural analysis through local strength evaluations will be performed to verify the efficiency of the optimum structural design for a lug structure.

• Journal of Environmental Impact Assessment
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• v.17 no.2
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• pp.125-132
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• 2008

It is desirable that implementation assessment (IA) should be carried out efficiently in order to make successful progress of Total Maximum Daily Load (TMDL) in watershed management. There are many difficulties in the process of the implementation assessment because of the early stage in the application of TMDL in Korea. This study reviewed the present status of IA and proposed the methodology of its improvement such as flexible application of TMDL ledger, and standardization of assessment index and criteria. The deficient time for assessment period could be corrected by the consideration of the post-procedure after the submission of IA report.

• Korean System Dynamics Review
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• v.5 no.2
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• pp.149-174
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• 2004

Since the economic crisis in 1997, the Korean government has implemented a number of reforms in order to eliminate inefficiencies in both private and public sectors. One of the reforms made in the public sector was to lower the retirement age of teachers from the original age of 65 to that age 62. The ultimate aim of this compulsory policy was to improve the quality level of education by hiring many young teachers instead of senior teachers. It was made based on the calculation that by lowering the retirement age by three years, the government can hire three young teachers with the saved wages. However, this policy has brought an unexpected result; the imbalance between the supply and demand for teachers has become a much more serious problem in Korea's elementary education system The purpose of this study is largely twofold; First of all, it aims to identify the scope of imbalances occurred in the supply-demand system of elementary school teachers in a region of the nation, and also to find out why such imbalance occurred. Secondly, the purpose of this study is to experiment with feasible policy alternatives and their effects on the system and to suggest some resolutions on the imbalance.

• Journal of Soil and Groundwater Environment
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• v.21 no.4
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• pp.10-19
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• 2016

Land contamination has emerged as a major environmental and land management issue over the last decade. Although the importance of contaminated land management was continuously increased and many developed countries tried to make advanced contaminated land register system, current Korea soil regulations and policies have not been considered yet. This study analyzed existing or developing contaminated land register system from various countries to suggest implications of environmental decision support. Through this study, the introduction of contaminated land management system as creating a new system in Korea needs to considerable review to the following in order to achieve the objective through a effective adoption and operation (1) we need to establish contaminated land register system by providing a proper legal basis before the imposition of data collection, investigation, and management, (2) sufficient examination is required to identify scope of information disclosure and criteria, contents, and subjects of items from contaminated land register system.

• Journal of Mechanical Science and Technology
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• v.19 no.3
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• pp.792-801
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• 2005

This paper discusses a dc motor equipped electric power steering (EPS) system and demonstrates its advantages over a typical hydraulic power steering (HPS) system. The tire-road interaction torque at the steering tires is calculated using the 2 d.o.f. bicycle model, in other words by using a single-track model, which was verified with the J-turn test of a real vehicle. Because the detail parameters of a steering system are not easily acquired, a simple system is modeled here. In previous EPS systems, the assisting torque for the measured driving torque is developed as a boost curve similar to that of the HPS system. To improve steering stiffness and return-ability of the steering system, a third-order polynomial as a torque map is introduced and modified within the preferred driving torques researched by Bertollini. Using the torque map modification sufficiently improves the EPS system.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.4
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• pp.339-350
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• 2000

The three-dimensional new corrdinate system over a single hill double hills and complex terrain with a single hill and a rectangular obstacle was generated using a body-fitted coordinate system. Control of the coordinate line distribution in the field was executed by generalizing the elliptic generating system to Poisson equation. ▽2ξ=P. The new coordinate system was well fitted to the surface boundary of single hill and double hills. But in the case of complex terrain with hill and rectangular obstacle there was smoothing tendency around the rectangular obstacle. In order to show the validity of the body-fitted coordinate system the heat diffusion equation was transformed and the temperature distribution was calculated over the various terrain. The results showed the temperature distribution was very symmetrical and stable around hills and obstacle. As a result the couple of a body-fitted coordinate system and the heat diffusion equation were executed successfully. Wind field over complex terrain with hill and rectangular obstacle which represent urban area was simulated stably in body-fitted coordinate system. The qualitative result show the enhancement of wind speed at the upwind direction of a hill and a rectangular obstacle and the recirculation zone at the downwind direction.