• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.25 no.5
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• pp.354-361
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• 2016

Parallel robots are usually used for performing pick-and-place motion to increase productivity in high-speed environments. The present study proposes a high-speed parallel robot and a control approach to improve the tracking performance for the purpose of handling a solar cell. However, the target processes are not limited to the solar cell-handling field. Therefore, a delta-type parallel manipulator is designed, and a ball joint structure is specifically proposed to increase the allowed angle that would meet the required workspace. A control algorithm considering the synchronization between multiple joints in a closed-chain mechanism is also suggested to improve the tracking performance, where the tracking and synchronization errors are simultaneously considered. In addition, a prototype machine with the proposed ball joint is implemented. A satisfactory tracking performance is achieved by applying the proposed control algorithm, with a cycle time of 0.3 s for a 0.1 kg payload.

• Journal of Soil and Groundwater Environment
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• v.20 no.4
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• pp.8-14
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• 2015

Plants grown in metal-contaminated sites have to be managed and disposed of safely even in phytoremediation because heavy metals can be transferred to other organisms through the food chain, which could result in bioaccumulation in organisms of a higher trophic level. However, if the harvested plants could be used for bioenergy, the ecological risk is reduced and phytoremediation improves economic feasibility. This study researched the effects of EDDS (Ethylenediamine disuccinate) on the heavy metal uptake performance of Brassica campetris and Sorghum biocolor, both of which have potential as bioenergy plants. The results showed that EDDS could increase Pb, Cu, Ni, Cd, and Zn concentrations in the roots and shoots of both of these plants. Furthermore, EDDS reduced the metal inhibition of the S. bicolor length growth. The translocation factors (TF) of S. bicolor and B. campestris are smaller than one for all five heavy metals tested and decreased by the following order: heavy metal + EDDS > heavy metals only > uncontaminated soil. The results suggest that with regard to plant growth and metal accumulation, S. bicolor treated with EDDS is more suitable than is B. campestris for the phytoremediation of soils contaminated with multiple metal species.

• Reproductive and Developmental Biology
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• v.29 no.4
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• pp.269-271
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• 2005

The freemartinism is the most frequent form of intersexuality found in cattle, and females of heterosexual twins become sterile. With increase of twinning rates due to transfer of multiple embryos derived from in vitro fertilization, it is of great economic value to establish early diagnosis of freemartins to remove infertile individuals from breeding stock. In the present study polymerase chain reaction (PCR) of two different Y-chromosome specific segments (BRY.l and AMX/Y) was performed to identify freemartins from twins and less common single born freemartins in Korean Native Cattle (KNC). Two male-specific sequences were amplified in all heterosexual twins tested (n=5). In addition, Y-specific PCR products were detectable in one of the single born females (n=4) with visible genital abnormalities. These results suggest that the sensitivity of PCR-based assay may be sufficient to detect freemartinism in single born females as well as female partners of heterosexual twins in KNC.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.5
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• pp.1856-1869
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• 2015

This paper addresses the issues of 3D human activity detection, tracking and recognition from RGB-D video sequences using a feature structured framework. During human tracking and activity recognition, initially, dense depth images are captured using depth camera. In order to track human silhouettes, we considered spatial/temporal continuity, constraints of human motion information and compute centroids of each activity based on chain coding mechanism and centroids point extraction. In body skin joints features, we estimate human body skin color to identify human body parts (i.e., head, hands, and feet) likely to extract joint points information. These joints points are further processed as feature extraction process including distance position features and centroid distance features. Lastly, self-organized maps are used to recognize different activities. Experimental results demonstrate that the proposed method is reliable and efficient in recognizing human poses at different realistic scenes. The proposed system should be applicable to different consumer application systems such as healthcare system, video surveillance system and indoor monitoring systems which track and recognize different activities of multiple users.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.81-87
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• 2001

In a dynamically changing environment, the manager of a maintenance and remodeling (M/R) program is confronted with an increasing complexity of coordinating and cooperating multi-resource constrained multiple projects. The root causes of the complexity, uncertainty and interdependence, cause an internal disruption of an activity and chain reactions of disturbance propagation that deteriorate the stability and manageability of the program. This paper evaluates previous endeavors to apply production control and management techniques to the construction industry, and investigates the possibility of applying other management concepts and theories to organizational program management. In particular, this paper proposes a buffer allocation model by which periodic buffers are allocated in the flows of program constraint resources to stabilize a program master schedule instead of protecting individual activities. Comparative experiments by Monte Carlo simulations illustrate improved performance of the proposed model in terms of program's goals: productivity, flexibility, and long-term stability.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.05a
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• pp.52-54
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• 2006

In the Langmuir-Blodgett (LB) technique, a monolayer on the water surface is transferred onto a substrate, which is raised and dipped through the surface. From this, multi layers can be obtained in which constituent molecules are periodically arranged. The LB technique has attracted considerable interest in the fabrication of electrical and electronic devices. Many researchers have investigated the electrical properties of monolayer and multiplayer films. Dendrimers represent a new class of synthetic macromolecules characterized by a regularly branched treelike structure. Multiple branching yields a large number of chain ends that distinguish dendrimers from conventional star-like polymers and microgels. The azobenzene dendrimer is one of the dendritic macromolecules that include the azo-group exhibiting a photochromic character. Due to the presence of the charge transfer element of the azo-group and its rod-shaped structure, these compounds are expected to have potential interest in electronics and ptoelectronics, especially in nonlinear optics. In the present paper, we give pressure stimulation to organic thin films and detect the induced displacement current.

• The Research Journal of the Costume Culture
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• v.8 no.1
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• pp.40-52
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• 2000

The purposes o this study were to investigate buying behaviors of patrons of six retail store types for clothing and the satisfaction levels of the six store types (department stores, specialty stores, chain store, discount stores, bonded goods stores and traditional market), and to test the differences in purchase behaviors and store satisfaction levels among the groups determined by demographic characteristics. A questionnaire survey was administered to male and female university students living in the Seoul metropolitan area from April 27 to May 11, 1999 ; 443 were collected and 391 were used for the data analysis. Data were analyzed by SPSS statistical package. Descriptive statistics, t-test, ANOVA, Chi-square analysis and Duncan's multiple range test were employed for the data analysis. In terms of the store usage, most of the subjects tended to choose the store types they patronized for buying coats, suits, blouses, T-shirts, slacks/skirts and jeans items ; but, they used department store and specialty store for coat, suit, blouse, T-shirt, slacks/skirt and jeans for purchasing selected clothing items. Regarding criteria used for store selection, the most important criterion was the diversity of products offered and other store types. In terms of the store satisfaction levels of the six store types, the patrons of all store types were most satisfied with the stores they patronaged.

• Clinical and Experimental Pediatrics
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• v.60 no.10
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• pp.333-336
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• 2017

Coxsackievirus A16 (CA16), which primarily causes hand, foot, and mouth disease (HFMD), is associated with complications, such as encephalitis, acute flaccid paralysis, myocarditis, pericarditis, and shock. However, no case of pancreatitis associated with CA16 has been reported in children. We report a case of CA16-associated acute pancreatitis in a 3-year-old girl with HFMD. She was admitted because of poor oral intake and high fever for 1 day. Maculopapular rashes on both hands and feet and multiple vesicles on the soft palate were observed on physical examination. She was treated conservatively with intravenous fluids. On the fourth hospital day, she had severe abdominal pain and vomiting. The serum levels of amylase and lipase were remarkably elevated (amylase, 1,902 IU/L; reference range, 28-100 IU/L; lipase, >1,500 IU/L; reference range, 13-60 IU/L), and ultrasonography showed diffuse swelling of the pancreas with a small amount of ascites. The real-time reverse transcription polymerase chain reaction result from a stool sample was positive for CA16. CA16 can cause acute pancreatitis, and should be considered in the differential diagnosis of abdominal pain in children with HFMD.

• Journal of the Korea Safety Management & Science
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• v.13 no.4
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• pp.117-124
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• 2011

Supplier selection is one of the most important activities of a company. This importance is increased even more by new strategies in a supply chain, because of the key role suppliers perform in terms of quality, costs and services which affect the outcome in the buyer's company. In addition, green production has become an important issue for almost every manufacturer and will determine the sustainability of a manufacturer. Therefore a performance evaluation system for supplier and green suppliers is necessary to determine the suitability of suppliers to cooperate with the company. Supplier and green supplier selection is a multiple criteria decision making problem in which the objectives are not equally important. In practice, vagueness and imprecision of the goals, constraints and parameters in these problems make the decision making complicated. The objective of this study is to construct a decision-making process using fuzzy analytic hierarchy process (FAHP) and balanced scorecard (BSC) for evaluating supplier and green suppliers in the manufacturing industry. The BSC concept is applied to define the hierarchy with four major perspectives and performance indicators are selected for each perspective. FAHP is then proposed in order to tolerate vagueness and ambiguity of information. Finally, FAHP is applied to facilitate the solving process. With the proposed approach, manufacturers can have a better understanding of the capabilities that supplier and green supplier must possess and can evaluate and select the most suitable supplier for cooperation.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.3
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• pp.458-466
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• 2011

In war time, minimizing the logistics response time for supporting military operations is strongly needed. In this paper, i propose the mathematical formulation for minimizing the maximal acquisition completion time in wartime or during a state of emergency. The main structure of this formulation is based on the traveling purchaser problem (TPP), which is a generalized form of the well-known traveling salesman problem (TSP). In the case of the general TPP, an objective function is to minimize the sum of the traveling cost and the purchase cost. However, in this study, the objective function is to minimize the traveling cost only. That's why it's more important to minimize the traveling cost (time or distance) than the purchase cost in wartime or in a state of emergency. I generate a specific instance and find out the optimal solution of this instance by using ILOG OPL STUDIO (CPLEX version 11.1).