• Journal of Hydrogen and New Energy
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• v.18 no.1
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• pp.40-45
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• 2007

Methylene blue(MB) was photocatalytically degraded with one-body photoanode and solar simulator to investigate the possible application to both environmental purification and photoelectrochemical cell for hydrogen production. Photoactive titanium dioxide was formed on both sides of Ti plate following steps such as rinsing-annealing-calcination or anodizing(20 V, 30 V)-annealing($350^{\circ}C$, $450^{\circ}C)$ after etching. The prepared titania plate($2cm{\times}2\;cm$, ca 1.6 mg $TiO_2$ on the basis of $1\;{\mu}m$ thickness) was used to degrade MB(10 ppm in 200 mL solution). The reaction tended to follow the Langmuir-Hinshelwood kinetics with zero order. Comparative experiments with Degussa P25 showed the same zero order kinetics when 2 mg of P25 had been used, while the first order kinetics when 200 mg used. This concludes the feasibility of the prepared titania plate as a material for the purification of low-level harmful organics and an electrode or a membrane for photoelectrochemical system for hydrogen production.

• Journal of Ship and Ocean Technology
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• v.3 no.4
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• pp.1-14
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• 1999

The improved Green integral equation using the Kelvin-type Green function in known free of irregular frequencies where the integral over the inner free surface integral is removed from the integral equation, resulting in an overdetermined integral equation. The solution of the overdetermined Green integral equation is shown identical with the solution of the improved Green integral equation Using the B-spline higher order panel method, the overdetermined equation is discretized in two different ways; one of the resulting linear system is square and the other is redundant. Numerical experiments show that the solutions of both are identical. Using the present methods, the exact values and higher derivatives of the potential at any place over the wetted surface of the body can be found with much fewer panels than low order panel method.

• Management Science and Financial Engineering
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• v.13 no.2
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• pp.117-139
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• 2007

This paper contributes by incorporating works addressing supply chain coordination and investing in setup reduction program. Consider a two-echelon, EOQ-like inventory system consisting of a supplier and a buyer. We assume that both the supplier and the buyer can invest in setup cost reduction programs in order to benefit from small order sizes. However, the costs of investing in setup cost reduction programs are different for the two parties, leading to mismatches in individually optimal setup costs and order cycle times. We propose a supply chain coordination contract that makes use of quantity discount as an incentive transfer scheme for supply chain coordination.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.32B no.1
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• pp.110-119
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• 1995

The lateral resolution in an ultrasound imaging system is one of the most important factors for quality of the image and is determined by the beam focusing. For the better lateral resolution SDF(Sampled Delay Focusing) capable of digital focusing was proposed. The second-order sampling, one of band-width sampling methods, is suggested as being the best suitable for SDF because it allows total digital processing and is simple and economical. By proving that it introduces too much error, this article shows the second-order sampling is not appropriate for sampling of the wide-band signal generally used in ultrasound imaging systems. Also, this article suggests new sampling methods that maintain the advantages and reduce the unavoidable errors of the second-order sampling method. From computer simulation it is expected that the proposed methods reduce the errors of the second-order sampling method and can be used in real applications.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.33B no.2
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• pp.20-27
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• 1996

In this paper, we propose a coprime factor model reduction method to get a reduced order controller in $H^{\infty}$ mixed sensitivity problem with frequency weighting functions. for this purpose, the given $H^{\infty}$ mixed sensitivity problem is transformed into robust stabilization problem with coprime factor uncertainty of given plant. This method is to define frequency weighted coprime factors of plant in CSD (chain scattering description) form and reduce the coprime factors using weighted balanced truncation. then a controller is designed to the reduced order coprime factors using J-lossless coprime factorization method. Using this approach, the robust stability condition is derived and good performance is preserved in closed loop system with the given plant and the reduced order controller. Also the order of reduced controller for guaranteeing the robust stability can be determined before designing the reduced controller. The proposed method behaves well in both stable and unstable plant.

• Journal of the Korean Society of Costume
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• v.24
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• pp.47-58
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• 1995

The Study is to find out the thought of costume of the people who advocated the Wejung-chunksa. Conclusions are described as follows 1. The action to boycott western goods was the early response in the Wejung -chuksa Thought. The reason were in fear of ruin in chosun industry and worry about the westernizing the Korean. 2. The people of the Wejung-chuksa had the conservative character in order to maintain the traditional public order and the costume. They thought that costume have a role to distinguish between man and woman , the rich and the poor and so on. Therefore acceptance the wastern constume style meant that the Korean became a savage. So that they rejected the King's order about the dress-system reformation in 1884, 1895. That pointed that their ultimate purpose was to keep the traditional rule. 3. In appearance the purpose of the short-hair law was good for health. But it meant to destory the traditional order and to symbolize the civilization . Especially the short -hair in the people of Wejung-chuksa meant the destruction of the traditional rule and casting away the courtesy. Therefore they wanted to keep the value of the traditional costume.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.33 no.2
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• pp.1-8
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• 2010

A vendor selection problem consists of two different kinds of decision making. First one is to choose the best suppliers among all possible suppliers and the next is to allocate the optimal quantities of orders among the selected vendors. In this study, an integration of the technique for order preference by similarity to ideal solution (TOPSIS) and a multi-objective mixed integer programming (MOMIP) is developed to account for all qualitative and quantitative factors which are used to evaluate and choose the best group of vendors and to decide the optimal order quantity for each vendor. A solution methodology for the vendor selection model of multiple-vendor, multiple-item with multiple decision criteria and in respect to finite vendor capacity is presented.

• IE interfaces
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• v.11 no.2
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• pp.199-209
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• 1998

In manufacturing industries, one of the critical issues is to synchronize the sequence of production operations with materials needed at each operation to improve productivity. In order to solve this synchronization problem. We develop a code system entitled 'Work-Order-Number' for automated storage/retrieval systems(AS/RS) in this paper. The Work-Order-Number is designed for the purpose of integrating the engineering information. material handling, production and operations scheduling, point of production, and AS/RS systems. This paper implemented the Work-Order-Number in the electric motor manufacturing. The results of the implementation showed the reduction of the number of workers in material handling and cost-loss due lo a late delivery.

• Journal of Electrical Engineering and Technology
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• v.7 no.4
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• pp.576-581
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• 2012

A 23 W continuous wavelength $CO_2$ laser system exited by a high-frequency LCC resonant converter is adapted to cut a biodegradable rope fabricated with polybutylene succinate. As the biodegradable rope consists of three twisted strands, the thickness changes relative to the position of the laser beam and we thus propose a method to determine exact cutting depth. In order to obtain the parameters related to the rope cutting, the experimental and theoretical cutting depths are compared and analyzed for a range of laser heat sources. The melted thickness and groove width of the cut biodegradable rope are also examined. The proposed theoretical cutting depth depends on the incident power and target velocity ratio. From these experimental results, the biodegradable rope with a diameter of 22 mm can be cut with a heat source of 50 J/cm resulting in a melted thickness of 1.96 mm and a groove width of 0.65 mm. The laser system is shown to be perfect tool for the processing of biodegradable rope without the occurrence of raveling.

• Journal of Korea Society of Digital Industry and Information Management
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• v.9 no.4
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• pp.69-79
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• 2013

A system of tracking a vehicle collects the vehicle location and then transmits the data into a GIS server in order to provide several service areas. An ODU built in the vehicle savesa GPS information data and communicates with the RSU installed in the road over the wave technology. The collected data in RSU is transmitted into the GIS serverand is stored. The system based on the collected GPS data in each vehicle is providing useful and various services between RSU and OBU. In this paper indicates that the system is designed in 2 phasesbased on the collected GPS data. The result comparing to process of GPS data created in 1 phase and 2 phase over the Web GIS service indicates that the capability of process of the GPS data in 2 phase is enhanced in "50.88% ~ 51.81%". Therefore, when the accident is happened the system of tracking the vehicle over GPS tech not only receives the information properly but also provides the emergence rescue services.