• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.404-409
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• 1999

The studies were carried out to investigate antimicrobial activity of mixture of Caesalpina sappan L. and Lithospermum erythrorhizon extracts against lactic acid bacteria isolated from Kimchi. The effects of the mixture and crab shell extracts on the shelf-life of Kimchi were also investigated. The growth of heterofermentative lactic acid bacteria and homofermentative lactic acid bacteria was inhibited by 98% ethanol extracts of Caesalpina sappan L. and Lithospermum erythrorhizon. The pH of Kimchi containing mixed extracts of Caesalpina sappan L. and Lithospermum erythrorhizon extracts (1 : 1) and crab shell was lower than that of control during fermentation for 25 days of $10^{\circ}C$. The viable cells of Lactic acid bacteria of the mixed extracts and crab shell added Kimchi were lower than that of control during fermentation. The sensory quality of the mixed extracts and Crab shell added Kimchi was a little inferior to control for during fermentation of Kimchi.

• Journal of Korean Society for Geospatial Information Science
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• v.23 no.2
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• pp.59-67
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• 2015

When planning for streams, adequate and definite flood control should be in the primary consideration of the planner; likewise, flood control is the basic prerequisite for the recent river restoration taking place nationwide. Planning 'safe' streams and rivers that are predictable and controllable begins from accurate survey data. In this research, we will create streams in 3D terrain models and apply them through hydraulic analysis and restoration using smart geospatial information. This process allows the extraction of more accurate data regarding streams and rivers, which makes possible precise hydraulic analysis that is superior in details to the conventional methods. The study also proposes optimal vertical section interval for efficient data processing on hydraulic analysis, applicable when LiDAR data is utilized on hydraulic analysis of urban streams. The study proposes 3D design plan and various applications for spatially planning and restoring rivers and streams.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.3
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• pp.713-720
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• 1996

In recent, the demand of mobile communication system is increasing rapidly. However, since wireless resources is limitted, the protocol to utilize wireless resource efficiently is needed. Up to now, Slotted CDMA_ALOHA(S_CDMA_ALOHA) and Mini-Slotted CDMA_ALOHA(MS_CDMA_ALOHA) methods are proposed as a CDMA_ALOHA mechanism, and it is turned out that MS_CDMA_ALOHA offers betterperformance than S_CDMA_ALOHA mechanism. Also, IS-95 multiple access mechanism has been proposed as common air interface(CAI) protocol of CDMA digital cellular system. However, in former study, the performance evaluations were made without considertion of chnnel characteristics of wireless communication environment. In this paper, a new access mechanism for improring the performance in the DS/CDMA digital cellular environment is suggested. This mechanism is adaptive to the channel condition and based on the conventional MS_CDMA_ALOHA mechanism. Also, the performance of new access mechanism is compared with that of conventional mechanisms, through computer simulation. According tot h simulation results, it is shown that the proposed NA_CDMA_ALOHA(Noise-Adaptation CDMA_ALOHA) mechanism offers better performance than conventional three CDMA_ALOHA mechanisms in view of mean delay time and system throughput characteristics. This phenomenon is due to the fast that NA_CDMA_ALOHA mechanism controls the access attempts efficiently based on the channel condition in heavy traffic environments.

• Journal of the Korea Society of Computer and Information
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• v.16 no.8
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• pp.129-135
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• 2011

In this paper, we propose a multi target's elevation angle estimation method using multi beam forming technique. This method make a stacked beam to digital processing a received signal in array element. There can be desired receiving beam to application weight value at antenna element in beam forming. Currently, we are to make multi stacked beam using fast fourier transform in stead of phase shifter to be a computer performance much improvement. Also, we improve multi beam directivity using beam steering error correction technique in order to beam steering to desired direction in receiver. Through simulation, we show that the proposed elevation estimation method based on fast fourier transform and beam steering error correction technique, improves th performance of target estimation compared to previous method.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.553-553
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• 2013

상압 플라즈마 기술은 표면처리, 온존 발생장치, VOC (Volatile Organic compound) 제거등 다양한 산업분야에서 응용되고 있다. 상압플라즈마 기술 또한 DBD (Dielectric barrier discharge), Griding Arc, SDIP (Surface Discharge Induced Plasma) 등 다양한 기술들이 개발되어져 왔다. VOC를 제거하기 위한 다양한 플라즈마 기술중 특히 BDB 방법과 SDIP 기술들은 플라즈마에 의한 VOC 분해 뿐만 아니라 오존 발생을 통하여 VOC성분을 분해하는 것으로 알려져 있으며 효율이 매우 뛰어난 것으로 보고 되고 있다. 그러나 BDB 방전의 경우 방전이 발생하는 간격이 매우 작아 공기를 정화시키기 위해 좁은 유로를 통하여 일정넓이를 이동하여하 하기 때문에 압력감소가 심하며 이를 개선하기위해 다단으로 설계할 경우 구조가 복잡하고 가격이 고가인 단점이 있다. 본 연구에서는 두 개의 면 전극이 마주보는 형태로 된 DBD 구조의 단점을 보완하기 위하여 빗살무늬 모양의 다층구조의 선형전극으로 구조를 변화시켜 전극에 의한 압력감소를 방지하고 효율적으로 플라즈마 및 오존을 발생시킬 수 있는 VOC제거용 상압 플라즈마 발생장치를 개발하였다. 또한 플라즈마 발생 및 오존발생량이 우수한 것으로 알려져 있는 SDIP 장치 또한 제작하여 비교 평가를 하였다. 제작된 플라즈마 발생장치는 60 Hz와 20kHz의 교류 고압파워 서플라이를 이용하여 플라즈마 발생실험을 진행하였다. 선행 연구에서는 60 Hz의 고압 파워 서플라이를 이용하여도 플라즈마 방전이 잘 된다고 보고되었는데 본 실험에서 60 Hz 파워 서플라이를 사용할 경우 15 kV 이상이 인가될 때 아주 약하게 오존이 발생하는 현상이 관찰되었으나 육안으로 구분이 될 만큼의 플라즈마 방전은 발생하지 않았다. 20kHz의 고압파워 서플라이를 사용한 경우에는 비교적 낮은 전압인 7 kV에서 방전이 관찰되었으며 분당 22 mg의 오존이 발생하였다. SDIP를 이용한 경우 플라즈마가 발생하는 조건은 SDIP의 기하학적 형상에 많이 의존하게 된다. 본 실험에 SDIP 장치는 매우 낮은 전압에서 방전을 시작하였다. 기존의 DBD와는 다르게 1.7 kV에서 플라즈마 발생하였으며 1.8 kV에서 정상적인 플라즈마 방전이 발생하였다. 이때 분당 3.1 mg의 오존이 발생하였다. 오존 발생양은 앞에 빗살형 플라즈마 방전장치에 비하여 낮은데 인가되는 전력을 고려하면 입력된 전기 에너지당 오존발생양은 비슷한 수준이였다.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.9
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• pp.857-861
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• 2010

Recently photochemical smog has become a serious urban air pollution. And VOC is the major pollutant for it. With the advance of industrialization and urbanization, MSWI fly ash and sewage sludge and melting slag were generated. It is necessary to de-toxificate ashes, because they contain many toxic constituents and probably lead to contaminate the environment. The objective of this research was to prepare multi-functional brick which is able to remove VOCs in ambient air. The bricks were made of MSWI fly ash, sewage sludge and slag. The benzene adsorption experiment by brick was acted to evaluate its adsorptivity. And also photocatalyst material was coated to enhance its adsorptivity and the endurance on the brick. According to the result, the benzene showed 74~96%. The removal efficiency was increased and the breakpoint time was lengthened by coating a brick.

• Journal of Korean Society for Geospatial Information Science
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• v.14 no.1 s.35
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• pp.29-36
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• 2006

In the process of location selection, it is assumed that transformer substation socially recognized as a dangerous facility require especially more rigorous and resonable process. This paper implements suitability analysis for optimum location selection of transformer substation in southern Gyeonggi province using AHP(Analytic Hierarchy Process) and spatial analysis of GIS in terms of safety, national land use, economical efficiency and environment preservation. To do this, necessary data from 1/5,000 digital map are extracted a s raster format for suitability analysis and a field investigation also was done. In the procedure of site selection, three candidate zones with 1.5km radius were selected for the whole research area and then through field survey low transformer sites were selected from candidate zones. In the last the appropriateness of selected sites was evaluated. The results of the suitability analysis showed that the first candidate site satisfied the location condition best and other candidate sites generally showed good location condition.

• Journal of Korean Society for Geospatial Information Science
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• v.3 no.2 s.6
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• pp.29-42
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• 1995

Route design in topographical plane map brings many problems in efficiency and requires much time and labor by hand Recently, the active studies of efficient route design method using 3-D terrain information are being developed according to increasing concentration on GSIS. In order to analyze terrain information for route design efficiently, this study presents objective and overall datum by applying SQL in construction and analysis of database and the possibility of three-dimensional terrain information analysis, This study generates 3-D base map on topographical map of scale 1:5,000 and acquires terrain information that have various thematic map data; contour, land use, roadway, and drange. This is a study on the application of SQL in route design and construction of the terrain information that linked by graphic datum of completed topographical map and attributed datum of database. As the result of this study, we can produce promptly and efficiently design datum of profile annotation, cross section, and volume computations to the preliminary route for route design and apply this efficient method to route design by understanding visual DTM which is composed of the roadway and the natural scene after design.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.3
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• pp.27-33
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• 2009

Content used in mashups is typically obtained from a third party source through a public interface or API (web services). Other methods of obtaining content for mashups include Web feeds (e.g. RSS or Atom), and screen scraping. A mashup or meshup Web application has two parts: A new service delivered through a Web page, using its own data and data from other sources. The blended data, made available across the Web through an API or other protocols such as HlTP, RSS, REST, etc. There are many types of mashups, such as consumer mashups, data mashups, and Business Mashups. The most common mashup is the consumer mashup, which are aimed at the general public. Examples include Google Maps, iGuide, and RadioClouds. 4D Wall-map display is data mashups combine similar types of media and information from multiple sources into a single representation. This technology focus data into a single presentation and allow for collaborative action among ITS-related information sources.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.3
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• pp.15-24
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• 2015

Jacket matrices which are defined to be $m{\times}m$ matrices $J^{\dagger}=[J_{ik}^{-1}]^T$ over a Galois field F with the property $JJ^{\dagger}=mI_m$, $J^{\dagger}$ is the transpose matrix of element-wise inverse of J, i.e., $J^{\dagger}=[J_{ik}^{-1}]^T$, were introduced by Lee in 1984 and are used for Digital Signal Processing and Coding theory. This paper presents some square matrices $A_2$ which can be eigenvalue decomposed by Jacket matrices. Specially, $A_2$ and its extension $A_3$ can be used for modifying the properties of hyperbola and hyperboloid, respectively. Specially, when the hyperbola has n times transformation, the final matrices $A_2^n$ can be easily calculated by employing the EVD[7] of matrices $A_2$. The ideas that we will develop here have applications in computer graphics and used in many important numerical algorithms.