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Simulated Radiances of the OSMI over the Oceans

  • Lim, Hyo-Suk;Kim, Yong-Seung;Lee, Dong-Han
    • Proceedings of the KSRS Conference
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    • 1998.09a
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    • pp.43-48
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    • 1998
  • Prior to launch, simulated radiances of the Ocean Scanning Multispectral Imager (OSMI) will be very useful to guess the real imagery of OSMI and to check the data processing system for OSMI. The data processing system for OSMI which is one sensor of Korea Mult i - Purpose Satellite (KOMPSAT) scheduled for launch in 1999 is being developed based on the SeaWiFS Data Analysis System (SeaDAS). Such a simulation should include the spectral bands, orbital and scanning characteristics of the OSMI and KOMPSAT spacecraft. The simulation is also very helpful for finding and preparing for problem areas before launch. This paper describes a method to create simulated radiances of the OSMI over the oceans. Our method for constructing a simulated OSMI imagery is to propagate a KOMPSAT orbit over a field of Coastal Zone Color Scanner (CZCS) pigment values and to use the values and atmospheric components to calculate total radiances. A modified Brouwer - Lyddane model with drag was used for the realistic orbit prediction, the CZCS pigment data were used to compute water - leaving radiances, and a variety of radiative transfer models were used to calculate atmospheric contributions to total radiances detected by OSMI. Imagery of the simulated OSMI total radiances for 6 nominal bands was obtained. As expected, water - leaving radiances were only a small fraction of total radiances and sun glint contaminations were observed near the solar declination. Therefore, atmospheric correction is very important in the calculation of pigment concentration from total radiances. Because the imagery near the sun's glitter pattern is virtually useless and must be discarded, more advanced mission planning will be required.

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Bayesian inference on multivariate asymmetric jump-diffusion models (다변량 비대칭 라플라스 점프확산 모형의 베이지안 추론)

  • Lee, Youngeun;Park, Taeyoung
    • The Korean Journal of Applied Statistics
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    • v.29 no.1
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    • pp.99-112
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    • 2016
  • Asymmetric jump-diffusion models are effectively used to model the dynamic behavior of asset prices with abrupt asymmetric upward and downward changes. However, the estimation of their extension to the multivariate asymmetric jump-diffusion model has been hampered by the analytically intractable likelihood function. This article confronts the problem using a data augmentation method and proposes a new Bayesian method for a multivariate asymmetric Laplace jump-diffusion model. Unlike the previous models, the proposed model is rich enough to incorporate all possible correlated jumps as well as mention individual and common jumps. The proposed model and methodology are illustrated with a simulation study and applied to daily returns for the KOSPI, S&P500, and Nikkei225 indices data from January 2005 to September 2015.

A Study on Introduction of Private Investigation (민간조사(탐정)제도의 도입방향 - 경비업법 개정을 중심으로 -)

  • Lee, Sang-Won
    • Korean Security Journal
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    • no.17
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    • pp.235-253
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    • 2008
  • In the developed countries, the private investigation system which is part of private security has developed together with police, and OECD countries except South Korea has developed the private investigation system establishing by the Private Investigation ACT. In Korea, there was several attempt to establish the Private Investigation ACT but it was not accomplished because of private security circumstances. In this study, the chapter Iis introduction, theoretical background is in chapter II, chapter III is the operation of private investigation of the developed countries, analysis and direction of the Private Investigation ACT in chapter IV, and conclusion in chapter V. To introduce the private investigation system, it is required to discover the problem of the Private Investigation ACT mentioned in this article and to develop the private investigation system by collecting the opnion of citizen, academic world, and the related agency. It is necessary to associated interest and effort of citizen, academic world, and the related agency for introdection of the private investigation system.

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Improved Static Element Stiffness Matrix of Thin-Walled Beam-Column Elements (박벽보-기둥 요소의 개선된 정적 요소강성행렬)

  • Yun, Hee Taek;Kim, Nam Il;Kim, Moon Young;Gil, Heung Bae
    • Journal of Korean Society of Steel Construction
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    • v.14 no.4
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    • pp.509-518
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    • 2002
  • In order to perform the spatial buckling and static analysis of the nonsymmetric thin-walled beam-column element, improved exact static stiffness matrices were evaluated using equilibrium equation and force-deformation relationships. This numerical technique was obtained using a generalized linear eigenvalue problem, by introducing 14 displacement parameters and system of linear algebraic equations with complex matrices. Unlike the evaluation of dynamic stiffness matrices, some zero eigenvalues were included. Thus, displacement parameters related to these zero eigenvalues were assumed as polynomials, with their exact distributions determined using the identity condition. The exact displacement functions corresponding to three loadingcases for initial stress-resultants were then derived, by consistently combining zero and nonzero eigenvalues and corresponding eigenvectors. Finally, exact static stiffness matrices were determined by applying member force-displacement relationships to these displacement functions. The buckling loads and displacement of thin-walled beam were evaluated and compared with analytic solutions and results using ABAQUS' shell element or straight beam element.

A theory and study on the LCM(Life cycle management) and evergreening according to the cases of patent litigation in the Korean pharmaceutical industry (제약분야의 특허분쟁사례를 통한 LCM과 에버그리닝의 이론과 논고)

  • Jung, Yun-Taek
    • Journal of Technology Innovation
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    • v.20 no.2
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    • pp.135-159
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    • 2012
  • To the analysis and discussion whether to conceptualization between the basis and LCM(Life cycle management) of patentability decisions and evergreening through research on patent application strategies and litigation cases. The Stakeholders have said that the LCM and evergreening strategies are an innovative effort to develop new pharmaceuticals, while others say that it is an effort to block generic pharmaceuticals from entering the market and permanently dominate the market by generic pharmaceuticals manufacturers or health economic perspectives. To achieve the goal of research, to discuss for conceptualization LCM and Evergreening strategies through patent application strategies for 14 pharmaceuticals for APIs and case studies for litigations. As a results, the LCM is getting patent rights for the results of research at the initial R&D stage and as such this shall be regarded as part of an effort for technology innovation. However, Evergreening is granting patent rights for the results by making high permission barrier to prevent the market entry of generic pharmaceuticals in the late development period during the pharmaceuticals development process or after their launch. This may lead to the problem of getting weak in health economic aspects and consumer welfare aspects by lowering the market accessibility of cheap generic pharmaceuticals.

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Study on the Disbonding of Stainless Steel Overlay Welded Metal(Report 2) - A Metallurgical Study on PWHT of Overlaid Austenitic Stainless Steel Weld Metals - (스테인레스강 Overlay 용접부의 Disbonding 에 관한 연구(2) - 오스테나이트계 스테인레스강 오버레이 용접금속의 PWHT에 관한 야금학적 고찰 -)

  • 이영호;윤의박
    • Journal of Welding and Joining
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    • v.2 no.1
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    • pp.4-17
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    • 1984
  • Overlaid weld metals of austenitic stainless steel in a pressure vessel of power reactor are usually post-weld heated for a long period of time after welding. The PWHT is considered as a kind of sensitizing and it is important to check the soundness of the weld metal after PWHT, especially about the precipitation of carbides. The purpose of this report is to obtain information on the relation between the change of microstructure and Post-Weld Heat Treatment in the overlaid weld metals. Metallurgical aspects of the problem on austenitic stainless steel heated at $625^{\circ}C$, $670^{\circ}C$, $720^{\circ}C$ and $760^{\circ}C$ for 3, 10, 30, 100 and 300 hours have been investigated by means of optical-micrography, micro-hardness measurement, scanning electron microscope and electron-probe micro analysis. From the results obtained, the following conclusions are drawn; 1) The PWHT above $625^{\circ}C$ for a long time causes a diffusion of carbon atoms from low alloy steel into stainless steel, and consequently carbon is highly concentrated at the boundary layer of stainless steel. 2) C in ferritic steel migrated to austenitic steel and carbides precipitated in austenitic steel along fusion line. At higher temperatures, the ferrite grains coarsened in the decarburized zone. 3) In the change of microstructure of stainless steel overlaid weld metal, the width of carbides precipitated zone and decarburized zone increased with increase of PWHT temperature and time. 4) At about $625^{\circ}C$ to $760^{\circ}C$, chromium carbides, mainly $M_{23} C_6$, precipitate very closely in the carburized layer with remarkable hardening. 5) Precipitation of delta ferrite from molten weld metal depends on solidification phenomenon. There was a small of ferrite near the bond in which the local solidification time was short, comparing with after parts of weld metal. Shape and amount of ferrite were not changed by Post-Weld Heat Treatment after solidification.

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Tenoscopy for Acute Septic Digital Flexor Tenosynovitis Treatment in 13 Thoroughbred Horses (관절경을 이용한 더러브렛 말의 급성 감염성 건초염 치료 13증례)

  • Seo, Jong-pil;Kato, Fumiki;Suzuki, Tsukasa;Yamaga, Takashi;Tagami, Masaaki
    • Journal of Veterinary Clinics
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    • v.33 no.1
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    • pp.1-5
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    • 2016
  • Septic tenosynovitis of the digital flexor tendon sheath (DFTS) is a potentially career-ending and life-threatening problem in horses. This study aimed to describe the outcomes of tenoscopy for the treatment of acute septic digital flexor tenosynovitis in horses. Tenoscopy was performed on 13 Thoroughbred horses with acute septic tenosynovitis of the DFTS. Surgical time was 56-148 min (mean 85.6 min, median 84.0 min). In the synovial fluid analysis, mean white blood cell count, mean neutrophil proportion, and mean total protein were $42.9{\times}10^3cells/{\mu}l$ (range, $7.2-109.5cells/{\mu}l$), 89.5% (range, 68-97%), and 4.0 g/dl (range, 2.5-5.2 g/dl), respectively. Microbial growth in the synovial fluid culture was detected in 2 of 11 horses. All horses survived and returned to their intended use without complications. The present study demonstrated that the tenoscopy is useful for treating acute septic tenosynovitis of the DFTS in horses.

Free and Forced Vibration Analysis of a Hard Disk Drive Considering the Flexibility of Spinning Disk-Spindle, Actuator and Supporting Structure (회전 디스크-스핀들, 액츄에이터와 지지구조의 유연성을 고려한 하드 디스크 드라이브의 고유 및 강제 진동 해석)

  • Seo, Chan-Hee;Jang, Gun-Hee;Lee, Ho-Seong
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2006.05a
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    • pp.660-665
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    • 2006
  • This paper presents a finite element method to analyze the free and forced vibration of a hard disk drive (HDD) considering the flexibility of a spinning disk-spindle with fluid dynamic bearings (FDBs), an actuator with pivot bearings, an air bearing between head-disk interface and the base with complicated geometry. Finite element equation of each component is consistently derived with the satisfaction of the geometric compatibility of the internal boundary between each component. The spinning disk, hub and FDBs are modeled by annular sector elements, beam elements and stiffness and damping elements, respectively. The actuator am, E-block, suspension and base plate are modeled by tetrahedral elements. The pivot bearing in the actuator and the air bearing between head-disk interfaces are modeled by the stiffness element with five degrees of freedom and the axial stiffness, respectively. A global matrix equation obtained by assembling the finite element equations of each substructure is transformed to a state-space matrix-vector equation, and both damped natural frequencies and modal damping ratios are calculated by solving the associated eigenvalue problem with the restarted Arnoldi iteration method. Modal and shock testing are performed to show that the proposed method well predicts the vibration characteristics of a HDD.

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Optimal Design of Hydraulic Device at the Seobyun Pumping Station using Genetic Algorithm (유전자 알고리즘을 이용한 서변 가압장 수리구조물의 최적설계)

  • Jeong, Bong-Seok;Kim, Ju-In;Kim, Sang-Hyeon;Park, Nam-Sik
    • Journal of Korea Water Resources Association
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    • v.33 no.3
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    • pp.289-298
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    • 2000
  • In order to minimize the impact of water hammer In a pipeline, a determination of optimum position of hydraulic structures with best operation of pressure relief valve was explored at the Seobyun pumping station. Method of characteristics is used to simulate a surge impact originating from abrupt stop of pumping operation in a pipeline. Genetic algorithm shows a powerful capability in searching a global solution, especially for a nonlinear problem The application results suggests that the maximum positive pressure can be relaxed by decreasing the opening time of pressure relief valve, meanwhile the maximum negative pressure can be relaxed by increasing the opening time of pressure relief valve. This study shows that the integration of a genetic algorithm with a transient analysis technique such as method of characteristic can improve the design of hydraulic structure in a pipe network.

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Health Status and Health Behavior of Adolescents by Socioeconomic Characteristics (사회경제적 특성에 따른 청소년의 건강상태 및 건강행태 비교)

  • Lee, Yong-Chul;Im, Bock-Hee
    • The Journal of Korean Society for School & Community Health Education
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    • v.11 no.2
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    • pp.13-28
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    • 2010
  • Objectives: The purpose of this study was to examine health status and health behavior of adolescents by socioeconomic characteristics. Methods: Secondary analysis of the 2008 Korea National Health and Nutrition Examination Survey was conducted for 836 adolescence respondents. Results: First, the score of health status was 3.75 and high in 12-15 ages, living together with parents and private medical insured person. The score of oral health status was 2.85 and high in 12-15 ages, employed health insured, living together with parents. Second, dental treatment need was high in female, low income and dental checkup high in 12-15 ages and high income. Influenza vaccination was high in 12-15 ages. Diet contents was good in high income, living together parents and private medical insured and having breakfast was high in male, 12-15 ages, high income, living together with parents and private medical insured person. Third, smoking experience was high in male, low income, living together with single father or mother and drinking age was high in high income family. Forth, sinusitis was high in high income and small pox was high in low income. Conclusion: There might be many differences in the health status and health behavior of adolescents by sex, age, house income, type of family, private medical insurance. Our findings suggest that the need to develop appropriate health education program for high health problem behavior and intervention strategies for socioeconomic specified groups at greater risk.

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