• Title/Summary/Keyword: Technical Issue

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Disk-averaged Spectra Simulation of Earth-like Exoplanets with Ray-tracing Method

  • Ryu, Dong-Ok;Kim, Sug-Whan
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.1
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    • pp.76.2-76.2
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    • 2012
  • The understanding spectral characterization of possible earth-like extra solar planets has generated wide interested in astronomy and space science. The technical central issue in observation of exoplanet is deconvolution of the temporally and disk-averaged spectra of the exoplanets. The earth model based on atmospheric radiative transfer method has been studied in recent years for solutions of characterization of earthlike exoplanet. In this study, we report on the current progress of the new method of 3D earth model as a habitable exoplanet. The computational model has 3 components 1) the sun model, 2) an integrated earth BRDF (Bi-directional Reflectance Distribution Function) model (Atmosphere, Land and Ocean) and 3) instrument model combined in ray tracing computation. The ray characteristics such as radiative power and direction are altered as they experience reflection, refraction, transmission, absorption and scattering from encountering with each all of optical surfaces. The Land BRDF characteristics are defined by the semi-empirical "parametric-kernel-method" from POLDER missions from CNES. The ocean BRDF is defined for sea-ice cap structure and for the sea water optical model, considering sun-glint scattering. The input cloud-free atmosphere model consists of 1 layers with vertical profiles of absorption and aerosol scattering combined Rayleigh scattering and its input characteristics using the NEWS product in NASA data and spectral SMARTS from NREL and 6SV from Vermote E. The trial simulation runs result in phase dependent disk-averaged spectra and light-curves of a virtual exoplanet using 3D earth model.

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Factors Influencing the Successful Implementation of the ERP System (ERP 시스템의 성공적 구현에 영향을 미치는 요인)

  • Kim, Byung-Gon;Oh, Jay-In
    • Asia pacific journal of information systems
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    • v.12 no.2
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    • pp.137-162
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    • 2002
  • As the ERP system become recognized as a strategic weapon of a firm, the way how to implement the system successfully has been an important issue for both practitioners and the academic community. The objective of this research is to identify the critical success factors influencing the implementation of the ERP system and to suggest the tasks to be considered first for the effective implementation of the system. The results from the analysis of data collected from the 169 firms among those which have implemented either the Oracle package or the SAP package in Korea are as follows. The important factors for the successful implementation of the ERP system include the strength of rivalry among competing firms; the degree to which information systems are matured; the information systems strategy of a firm; the support and concern from the top; and the technical openness between the ERP system and the legacy system such as network, hardware, and software. The tasks to be considered first for the effective implementation of the ERP system cover the same degree of feeling between labor and management on the threat to survive; the formulation of information systems strategy at the strategic level; CEO's strong will and resolution; the process automation and informatization of a firm; and the infrastructure including intranet and databases.

A Study on Access Authorization Inference Modes for Information Security of Specialized Private Networks (특성화 사설 네트워크 정보보호를 위한 접근권한 추론모드에 관한 연구)

  • Seo, Woo Seok
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.10 no.3
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    • pp.99-106
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    • 2014
  • The most significant change and trend in the information security market in the year of 2014 is in relation to the issue and incidents of personal information security, which leads the area of information security to a new phase. With the year of 2011 as the turning point, the security technology advanced based on the policies and conditions that combine personal information and information security in the same category. Such technical changes in information security involve various types of information, rapidly changing security policies in response to emerging illegal techniques, and embracing consistent changes in the network configuration accordingly. This study presents the result of standardization and quantification of external access inference by utilizing the measurements to fathom the access authorization performance in advance for information security in specialized networks designed to carry out certain tasks for a group of clients in the easiest and most simple manner. The findings will provide the realistic data available with the access authorization inference modes to control illegal access to the edge of a client network.

An experimental study on the development and verification of NCC(new concrete cutting) system

  • Park, Jong-Hyup;Han, Jong-Wook
    • Structural Engineering and Mechanics
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    • v.65 no.2
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    • pp.203-211
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    • 2018
  • This paper introduces the development process of NCC(New Concrete Cutting) system and analyzes first verification test. Based on the first verification test results, some problems of NCC system have been newly modified. We carry out the second verification test. We tried to verify cutting performance and dust control efficiency of NCC system through the cutting test of concrete bridge piers. In particular, this verification test strives to solve the problem of concrete dust, which is the biggest problem of dry cutting method. The remaining dust problems in cutting section tried to solve through this verification test. This verification test of the NCC system shows that the dust problem of dry cutting method is closely controlled and solved. In conclusion, the proposed NCC method is superior to the dry cutting method in all aspects, including cutting performance, dust vacuum efficiency and cooling effect. The proposed NCC system is believed to be able to provide eco-friendly cutting technology to various industries, such as the removal of the SOC structures and the dismantling of nuclear plants, which have recently become a hot issue in the field of concrete cutting.

The Basic Component Technologies for the Guarantee of Metadata Interoperability (메타데이터의 상호운용성 보장을 위한 요소기술)

  • 이수상
    • Journal of Korean Library and Information Science Society
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    • v.34 no.1
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    • pp.91-109
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    • 2003
  • One of the main issues in developing a digital library is how to implement an open digital library which can be interoperable, and diverse concepts, technology and protocols have been introduced to deal with this issue. In this study, it is analysed in terms of 'metadata interoperability', and based on the analysis, 5 basic component technologies are defined as follows: application profiles, modeling, implementation, resource discovery, portal service. Therefore it explains concepts of those core features, characteristics, cases in point, standardization and technical trends.

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Extraction and Specification Technique of Java Components for Reuse of Java Programs (자바 프로그램의 재사용을 위한 자바 빈즈 컴포넌트의 추출 및 명세화 기법)

  • Lee, Seong-Eun;Kim, Yeong-Ik;Ryu, Seong-Yeol
    • The Transactions of the Korea Information Processing Society
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    • v.7 no.5
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    • pp.1388-1400
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    • 2000
  • An important technical issue in recent software development is to make needed software by the composition of components that are assemblable, and configurable, and independently extracted. The main advantage of component-based software development is reducing development time and cost. It is more cost-effective in development time to use components that are already developed than developing from scratch. There are two ways of component-based software development: one is to compose self-developed components, and the other is to by the components developed by third-parties and compose them. In the second case, existing non component programs must can be used for reuse in the component development. In this paper, we approach two methods for increase of reusability of Java program. First, we suggest the technique of extracting the elements suitable for the Beans component model from Java program, and then we show a process and a guideline of converting the extract elements into the Beans component model. Second, we suggest a technique of automatically extracting component information from the Java Beans component, expressing them in XML, its is possible to reuse the efficient component environment.

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Conflict Structure of Urban Growth Management Policies and Conflict Mitigation Alternatives : Lessons from the United States' Experience (도시성장관리정책의 갈등 구조 및 조종 미국 도시성장관리정책의 교훈)

  • 전명진;박성희
    • Journal of the Korean Regional Science Association
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    • v.13 no.2
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    • pp.143-155
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    • 1997
  • This study aims at drawing implications for Korea's urban growth management policies from U.S.A's experience on this issue. This study analyzes two types of contradictions in planning and implementing urban growth management policies: 1) value conflicts in goal setting and 2) contradictions among different level of governments (local, province, nation). As mentioned by Campbell (1996), there are three types of conflicts in objective values (efficiency, equity, and environment protection): property contradiction between economic growth and equity, resource conflict between efficiency and environment protection, and development conflict between equity and environment protection in urban growth management policies. In implementing urban growth management three types of conflicts in goal values should been taken into consideration. Contradictions among local governments, province, and central government are also found in implementing growth management policies. The lessons from the United State are as follow: 1) growth management plans are initiated by the local government and during the planning process adjacent local governments review a local government's growth management plans and give inputs for the plan, 2) local government and State work together for growth management planning and specially, the State provides technical and financial assistance to local government, and 3) the State plays leading roles in local government's planning and implementing of growth management policies with carrot and stick policy.

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The Technological Concept of Fibroscan and its Clinical Usefulness in the Traditional Korean Medical Field (비침습적 간섬유화 측정기(Fibroscan)의 기술적 개요와 한의임상적 유용성 고찰)

  • Son, Chang-gue
    • The Journal of Internal Korean Medicine
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    • v.36 no.2
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    • pp.85-92
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    • 2015
  • Objectives: The liver fibroscan has been developed as a noninvasive and convenient method to assess hepatic fibrosis. This study aimed to review this device in terms of its technological concept and clinical application in traditional Korean medicine (TKM). Methods: The technological background, diagnostic evaluation, and clinical usefulness of fibroscan were reviewed using various literature and clinical studies. One clinical example-a patient with hepatofibrosis who had been treated with TKM-is presented. Results: The liver fibroscan was approved as a medical device for noninvasive measurement of the hepatic fibrosis level by the Korean Food and Drug Administration (KFDA). Numerous clinical studies have confirmed that its sensitivity and specificity allow it to serve as a substitute for liver biopsy, the present gold standard diagnostic method. The accuracy and reproducibility and lack of technical risks are strong points of the fibroscan; however, it has some limitations for application, especially in patients with obesity or severe hepatitis. One clinical example showed the applicability of the liver fibroscan in herbal medicine-based treatments. Conclusions: The requirement for diagnostic medical devices is an important issue in TKM; therefore, this study provides valuable information for practitioners of TKM.

A Study on the Cooling Parameter Decision of Linear Motor System by Finite Volume Method (유한체적법을 이용한 리니어모터 시스템의 냉각조건 선정에 관한 연구)

  • Hwang Y.K.;Eun I.E.;Lee C.M.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2006.05a
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    • pp.449-450
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    • 2006
  • Development of a feed drive system with high speed, positioning accuracy and thrust has been an important issue in modern automation systems and machine tools. Linear motors can be used as an efficient system to achieve such technical demands. By eliminating mechanical transmission mechanisms such as ball screw or rack-pinion, much higher speeds and greater acceleration can be achieved without backlash or excessive friction. However, an important disadvantage of linear motor system is its high power loss and heating up of motor and neighboring machine components on operation. For the application of the linear motors to precision machine tools an effective cooling method and thermal optimizing measures are required. In this paper presents an investigation into a thermal behavior of linear motor cooling plate. FVM employed to analyze the thermal behavior of the linear motor cooling plate, using the ANSYS-CFX.

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CFD Analysis on a Tall Building Augmented Wind Turbine (풍력발전기가 설치된 고층빌딜에 대한 전산유체역학적 고찰)

  • Jeon, Wan-Ho;Yoon, Seong-Wook;Kim, Wook;Cho, Jang-Hyung
    • 한국신재생에너지학회:학술대회논문집
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    • 2009.11a
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    • pp.418-421
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    • 2009
  • Renewable energy or green energy is a hot issue in theses days. Since wind resource can be endlessly supplied by nature, researchers and common people are interested in study how to use that resource at home or company. Especially, many architects have tried to integrate wind power generator for a part of building. So in this paper, three buildings installed wind power turbine are targed to CFD analysis and these buildings are Bahrain trade center, Discovery tower, and Pearl river tower. Bahrain trade center is the first builidng installed real wind turbine, Discovery tower is constructing at Texas, and Pearl river tower is designed and proved by china researchers. These buildings have very different type of wind power turbine and each turbine has different conditions for best power generation. Therefor this paper will focus on characteristic shape of buildings, wind power turbine type, and expected purpose of construction. Moreover, CFD analysis will show wind flow pattern and wind speed while wind is passing through wind turbine of three tall buildings. CFD analysis for three buildings make comparison the wind flow patterns with experimental result.

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