• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.12
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• pp.1886-1902
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• 1989

In this paper we discuss the generating algorithm of Kumar code sequences which are based on generalized bent sequences for FH-CDMA. The code sequence generator was constructed for the shift register stages n=4 over GF (5). Finally we analyze the characteristics fo Hamming correlation between two code sequences and the time-frequency correlatins of the complete waveform with the sinusoidal chips as the elemental waveforms.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.749-750
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• 2010

• The Pure and Applied Mathematics
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• v.8 no.2
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• pp.163-174
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• 2001

In this paper we modify two indicators related to the global avalanche criterion (GAC) and discuss their properties. Also, we apply the modified indicators to measure the GAC of S-boxes of DES.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.7
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• pp.79-88
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• 2018

In the late Koryo Dynasty~early Joseon Dynasty, nationwide distribution of Ondol prompted the formation of ㄱ-shaped corner space. From this background, the spatial form changed according to the space function. In the case where the ondol is located in the bent portion, it would have formed a similar spatial form nationwide at the beginning of the 16th century. Until the middle of the 16th century the receptionists and the family rituals were carried out in the inner of the house, so ㄱ-shaped corner space gradually expanded. Also a special structure type using fultile rafters was used to cover the upper structure of the extended folded space. From the 17th century, ㄱ-shaped corner space was varied from wide and high to narrow and low. In addition to this, the space function of ㄱ-shaped corner is a small hall, a wooden floored room, and the kitchen. And Their spatial form also changes over time.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.2
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• pp.254-266
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• 2005

The purpose of this study were to develop snow-board upper wear with improved functionality. The study consisted of figure out appropriate ease amount of snow-board upper wear and make products by applying it to pattern design. The results of this study were as follows : First, The results of examined the difference between naked body measurements of and basic wear. According to motion, chest circumference(4.7cm, 5.1%), back width(8.9cm, 20.7%), and waist back length(8.0cm, 18.3%) increased. Around the elbow the length increased by 4.4cm(21.9%) when it was bent 90 degrees, while it increased by 6.0cm(29.8%) when it was bent to the full(145 degree). Second, 3 snow-board upper wear were selected and evaluated their appearance, comforts, and functionality, and that of the biggest margin proved to be the best. Eases necessary for motion proved to be insufficient especially in neck, arm and wrist parts of upper clothing. Third, on the basis of the analysis of snow-board upper wear on market, 2 pieces of experimental snowboard upper wear were designed, produced, and evaluated the patterns of with different ease, and snowboard upper wear B for experiment was proved to be better, Fourth, Snowboard upper wear was produced and evaluated for experiment 2 by giving additional ease to specific parts. Therefore experiment 2 was presented pattern, ease, and size of snowboard upper wear for with snowboard upper wear with improved functionality.

• Journal of the Korean Society for Nondestructive Testing
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• v.24 no.4
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• pp.307-314
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• 2004

A circumferential guided wave method was developed to detect the axial crack on the bent feeder pipe. Dispersion curves of circumferential guided waves were calculated as a function of curvature of the pipe. In the case of thin plate, i.e. infinite curvature, as the frequency increases, the $S_0$ and $A_0$ mode coincide and eventually become Rayleigh wave mode. In the case of pipe, however, as the curvature increases, the lowest modes do not coincide even in the high frequencies. Based on the analysis, a rocking technique using angle beam transducer was applied to detect an axial defect in the bent region of PHWR feeder pipe. Based on the analysis of experimenal data for artificial notches, the vibration modes of each signal were identified. It was found that the notches with the depth of )0% of wall thickness can be detected with the method.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.232-239
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• 2001

Young Jong Grand Bridge is approach traffic road of New Inchon International Airport which covers hub airport function in northeast asia. The total span length of this bridge is $4,420{\cal}m$ and this main bridge type is, the first in the world, Double Deck Self Anchored Suspension Bridge, designed as double deck systems to be arranged by road and railroad. Approach bridges to be connected with main span also are composed double deck steel truss and steel box girder to consider a continuity with this span. Our company erected $1,375{\cal}m$(about 60,000tons) of double deck steel truss bridge type which is composed by 6 traffic lane on upper deck and 4 traffic lane and Double track railroad on lower deck. The original installation method of this bridge was planed to install about 75 meters bridge blocks to use floating crane, after temporary bent was constructed between permanent piers. But this method which had to construct many temporary bents in the sea had the matter that construction periods can become lengthen and construction cost can be risen. To overcome the uncertainty to ensure high qualify of bridge and economic project execution, our company developed new bridge erection method to assure both quality control and economic construction work. The new erection method which was developed by us was one that could transport and install long bridge block, $120{\cal}m$ unit at a time and that temporary bent was not required. We hope that this paper is used as technical data which will erect bridge in the western sea and others marine region.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.731-736
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• 2000

An optimal design method is adopted for a spacer grid in nuclear power plant. It is made of punched sheet metal process, functioning as springs and dimples supporting fuel rods. For stress analysis of the assembled fuel rod support, a typical cell out of the repeated pattern in the assembly is modeled using 4-node shell elements. A commercial code, ABAQUS, is used for detailed analysis of contacting phenomena with friction. For the optimization, design varibles are taken from geometric parameters representing the shape of the bent leaf spring part and mating contact region with fuel rod. Objective function is considered in relation to mechanical functions and durability. Maximum yon Mises stress is considered in relation to constrained contact stress.

• Journal of Nutrition and Health
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• v.49 no.1
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• pp.1-7
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• 2016

Purpose: The aim of this review is to comprehensively summarize the definition of vitamin D as a nutrient as well as a hormone-like molecule and its new function in prevention of various chronic diseases. Methods: The review was written by the method for systematic reivew writing. Literatures from the various sources, including research articles, book chapters, proceedings and electronic materials as appropriate, were screened first and then reviewed and analyzed for the review. Results: Vitamin D was originally considered as the essential nutrient as a vital carbon compound and was first discovered among children with osteomalacia, also known as ricket disease, characterized by poorly calcified bones which were easily bent rather than broken. Since that time, vitamin D has been known as the key nutrient to improve bone health. However, recently emerging study findings have shown that vitamin D acts as the hormone-like nutrient since it is synthesized like a hormone when our body needs and this particular vitamin also acts like a cell signaling ligand which regulates gene expression of various proteins. So far positive effects of vitamin D have been suggested for the action of anticancer, anti-immune function, and anti-cardiovascular disease, as well as antidiabetic function, etc. In this review, the definition for vitamin D as a nutrient vitamin as well as a hormone-like molecule, cell signaling mechanism of vitamin D, and finally the potential role for the prevention of chronic diseases are discussed. Conclusion: Vitamin D is now being considered as a vital nutrient as a vitamin and as a potential substance for prevention of several chronic diseases.

• Journal of electromagnetic engineering and science
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• v.5 no.3
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• pp.140-145
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• 2005

In this paper, an experimental investigation for return loss and a software-based prediction for interference level of single-packaged filtering antenna composed of dielectric waveguide filter and PCB(Printed Circuit Board) slot antenna in transceiver module have been carried out with several different feeding structures in millimeter-wave regime. The implementation and embedding method of the existing air-filled waveguide filters working at millimeter-wave frequency on general PCB substrate have been described. In a view of the implementation of each components, the dielectric waveguide embedded in PCB and LTCC(Low Temparature Co-fired Ceramic) substrates has employed the via fences as a replacement with side walls and common ground plane to prevent energy leakage. The characteristics of several prototypes of filtering antenna embedded in PCB substrate are considered by comparing the wideband and transmission characteristics as a function of bent angle of transmission line connecting two components. In addition, as an essential to the packaging of transceiver module working at millimeter-wave, miniaturization technology maintaining the performances of independent components and the important problems caused by integrating and connecting the different components in different layers are described in this paper.