• Journal of the Korean Society for Railway
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• v.16 no.6
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• pp.519-527
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• 2013

Mobile radio technologies have evolved in the railway industry offering seamless connectivity and various functionalities to improve railway service. Recently, advanced mobile communication technologies have enabled a new level of railway customer services with more efficient railway operation. Since the LTE mobile communication technology offers many benefits and better performance for new railway services, it is considered to be a strong candidate for the future railway mobile telecommunication. However, communication networks in the railway sector are critical for secure operation and have stringent requirements for reliability and safety. In this paper, we explain the requirements for the future railway mobile telecommunication. The LTE, which would be the future railway mobile technology, is analyzed against these requirements. We also introduce the current state of standardization for the future railway mobile telecommunication and its implementation plan.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.1
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• pp.179-185
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• 2012

Since the eco-era is getting closer, the importance of noise reducing in the passenger cars of high-speed train is very important. The active noise control is best choice to reduce low frequency noise because the passive one is too heavy for high speed trains where weight is so critical. Also ANC is able to reduce the ambient noise when the environmental-factor changes. To reduce a three-dimensional closed-space sound field like a car of a high-speed rail is hard to do using single channel ANC control system. We used multi-channel FXLMS algorithm which calculation speed is fast and the secondary path estimation is possible in order to take into account the physical delay in electro acoustic hardware control loudspeaker and power amplifier. Firstly, we have measured interior noise of KTX and estimated noise path in KTX test-bed. However there was some problem related to algorithm divergence and increasing the filter order. We have made a simulation of interior environment of KTX car by using three frequency bands of 120Hz, 280Hz, 360Hz as the most important for KTX ANC system. During this research the interior noise reduction of KTX car was made by using the multi-channel FXLMS algorithm. Reduction performance was evaluated and compared each other for open space section and tunnel section. in-situ experiment for the KTX noise reduction by proposed ANC was performed based on data obtained in simulation and they were compared for open space section and tunnel section as well.

• Journal of Institute of Control, Robotics and Systems
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• v.6 no.12
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• pp.1106-1112
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• 2000

In this paper, we present a vision system which measures the cross-section of a hot wire-rod in the steel plant. We developed a mobile vision system capable of accurate measurement, which is strong to vibration and jolt when moving. Our system uses green laser light sources and CCD cameras as a sensor, where laser sheet beams form a cross-section contour on the surface of the hot wire-rod and the reflected light from the wire-rode is imaged on the CCD cameras. We use four lasers and four cameras to obtain the image with the complete cross-section contour without an occlusion region. We also perform camera calibrations to obtain each cameras physical parameters by using a single calibration pattern sheet. In our measuring algorithm, distorted four-camera images are corrected by using the camera calibration information and added to generate an image with the complete cross-section contour of the wire-rod. Then, from this image, the cross-section contour of the wire-rod is extracted by preprocessing and segmentation, and its height, width and area are measured.

• Journal of Acupuncture Research
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• v.15 no.2
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• pp.43-60
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• 1998

This study examined the histomorphomeric and histological changes of the left and right kidney in uninephrectomized rat. The results were as follows: 1. In the control, the right kidney was more prominent than the left in the basement membrane of glomerular capillaries. The podocyte had well developed Golgi apparatus in the left kidney and rough endoplasmic reticulum in the right kidney. 2. At the 30 days after unilateral nephrectomy, the basal lamina of glomerular capillaries was prominently thickened in the right kidney. The cytoplasm of the podocyte of the left kidney was markedly increased and had free ribosomes, developed Golgi apparatus and rough endoplasmic reticulum. 3. At the 30 days, the section of the glomeruli were more enlarged in the left kidney than in the right. 4. At the 20 day, the nuclear section of the podocytes were markedly enlarged in the right kidney, but those of the left kidney were diminished. The mitochondrial section of the podocytes were prominently increased in the right kidney. 5. The nuclear section of the parietal layer lining cells was no significant change in the right kidney. That of the left kidney was increased at the 20 days and decreased at the 40 days. The nuclear section of glomerular endothelium of the left kidney increased earlier than the right. 6. In the morphometry of the control kidney, the section areas, long and short diameters, the nuclear section, the mitochondrial section of the proximal tubule cells, and the changes of those were more large in the right kidney than in the left. 7. The luminal secretory vesicles and peroxisomes of the left kidney were more than the right at the 20 days. The increase of mitochodrial section in the proximal tubule cells of the left kidney was more prominent than the right. The large cytoplasmic vacuoles were more prominent in the left kidney than in the right. 8. The thickness of cytoplasm and brush border was more thick in the control left kidney than in the control right. The change of cytoplasmic thickness of the left kidney was increased earlier than in the right and both kineys were increased in the thickness of brush border at the 30 days.

• Electronics and Telecommunications Trends
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• v.8 no.3
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• pp.39-52
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• 1993

This study involves a Common Cause Failure (CCF) problem on the ultra-high reliability required system development such as war game operations, nuclear power control, air traffic control, space shuttle missions, and large scale network communication system. The system situation problems are defined according to CCF, reliability and system fault identifications for the development cast verifications in the multi-version redundant software system. Then, CCF analysis of redundant system, system principles and statistical dependence are also described. This validation oh the CCF in the human software interaction system will notify software engineers to conceive what really is CCF contribution factor, not only the internal but the external ones.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.643-644
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• 2009

• Journal of Korean Institute of Industrial Engineers
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• v.20 no.2
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• pp.77-90
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• 1994

Curve-net interpolation surface is one of the most popular method in engineering design. Therefore it is supported with many commercial CAD/CAM system. However, construction algorithm of curve-net interpolation surfaces is rarely opened to the public because of its copy-right. In this paper we establish a construction algorithm of curve-net interpolation surface so called sweeping surface which especially concentrates on trajectory of cross-section curve. We also show the method which can construct sweeping surfaces as NURB or Bezier mathematical models. Surfaces having the form of standard mathematical models are very useful for the application of joining, trimming, blending etc. The proposed surface interpolation scheme consists of four steps; (1) preparation of guide curves and section curves, (2) remeshing guide curves and section curves, (3) blending section curves after deformation, and (4) determination of control points for sweeping surface using gordon method. The proposed method guarantee $G^1$-continuety, and construct the surface salifying given section curves and trajectory of section curves.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.12
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• pp.2505-2510
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• 2009

Semiconductor processes need measurement to confirm where there are problems in quality after progresses manufacturing process. This paper suggests equipment and automatic measure sampling method that control monitoring ratio according to change point occurrence availability of process that is not measure method by the existent simple ratio rate. This paper defines measure section as ailment section, metastable section and stability section by change point standard and create statistical model of each section and developed suitable measure rate model by section. As a result, we have accomplished maximum throughput and minimum sampling number that needs to maintain constant level of quality. Proposed method minimizes load of measure process by brings production quality sophistication and decrease of process badness and lowers measure rate in stable section making perception about problem occurrence quick heightening measure rate at change point occurrence.

• Journal of Korean Academy of Nursing Administration
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• v.6 no.2
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• pp.211-225
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• 2000

With the drastically changing healthcare market, the adoption of DRG system and the use of Critical Pathway will be increased gradually in order to care hospitalized patients qualitatively and manage cost-effectively in Korea. The purpose of this quasi-experimental research is to apply and analyze the developed critical pathway to the patients with Cesarean section. 35 eligible subjects for the control group were chosen from postpartum patients who has delivered at H-hospital in Kwang-ju, and were questioned after appling previous care plan from May to December, 1998. For the experimental group, 37 subjects were chosen and questioned after applying Critical Pathway service from January to June, 1999. The instruments are a critical pathway for the patients with Cesarean section developed by chung(1998) and a questionnaire that evaluate patients and family members' satisfaction level. Also, educational materials were used to inform them in the process of Critical Pathway application. As a result of chi-square test on general characteristics, there is significant difference between control group and experimental group only in terms of room size(p= .010). There are no significant differences in the average length of stay in the hospital between control group and experimental group(t=.078). Also, the average medical consult fee has no difference significantly between two groups(t= .105). The findings showed that the experimental group with critical pathway service scored significantly higher than control group on the satisfaction level toward care services(p=.000). The items are post-operative care, postpartum exercise technique, breast feeding and breast manage through educational materials. In conclusion, the research indicates that the application of planned Critical Pathway can have a positive impact on satisfaction level of inpatients with Cesarian section.

• Korean Journal of Community Nutrition
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• v.6 no.4
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• pp.657-667
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• 2001

This study was designed to develop a website for providing nutrition information and education for college women and young women. The website focuses on two topics ; general nutrition and desirable weight control. This program is located at http : // www.ezydiet.co.kr. This program is composed of 5 major sections. The first two sections were designed to provide information ; one for general nutrition, and the other for providing information regarding weight control. The first section includes information regarding young adult women's diet, nutrition standards, such as the RDA or Korean Food Pyramid, drinking and smoking. The second section coveres information regarding desirable control, foods with high or low calories, eating disorders and popularly used dieting methods. The third section is for simple nutrition assessment, consisting of assessment of ideal body weight and obesity, energy requirements, and eating habits. The fourth section was designed to introduce and help users to apply behavioral modification techniques, such as monitoring, goal setting, stimulus control and reinforcement. The final section was designed for meal planning, by introducing a food exchange list and menu examples for one week. The characteristics of this web-based program are as follows ; 1) provide nutrition information systematically, 2) involve sections for the participation of the user, 3) include food pictures to help understanding of nutrition information, 4) include management modules for some sections to revise or update the information. One-hundred and ten female university students participated in the evaluation of this website. The evaluation results were favorable. About 90% of subjects rated that this program covers major topics 'well ' or 'very well', and that it was 'easy'to 'very easy'to understand the contents on website. Two-thirds of subjects rated quite positively on questions regarding attractiveness, overall quality and technical quality of website. In addition, about three-fourths of subjects answered that this website was helpful in increasing nutrition knowledge and in applying nutrition information into daily life. These results suggested the possibility of using a website as a means of providing nutrition information and education for young adult women.