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Analysis on the Efficiency and Productivity Change of Non-Life Insurance Industry between Pre-Execution and Post-Execution of Capital Market Law (자본시장통합법 시행 전후의 손해보험산업의 효율성 및 생산성 변화 분석)

  • Kang, Ho-Jung
    • The Journal of the Korea Contents Association
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    • v.11 no.12
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    • pp.403-412
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    • 2011
  • The execution of capital market law causes severe competition by promoting restructuring of financial industry. This study analyze efficiency and productivity change of the Korean Non-Life Insurance industry between pre-execution and pre-execution of capital market law using DEA model and Malmquist Index. Additionally, this study finds determinants of efficiency using tobit regression. The main results of this study can by summarized as follows. First, the efficiency with post-execution was increased comparing with pre-execution of capital market law significantly. Second, the productivity with post-execution was increased comparing with pre-execution of capital market law significantly. Third, significant determinants of technical efficiency and pure technical efficiency are weight of life planner. operation rate of assets respectively. And significant determinant of scale efficiency are firm size, operation rate of assets, weight of life planner.

A correlation method for high-frequency response of a cargo during dry transport in high seas

  • Vinayan, Vimal;Zou, Jun
    • Ocean Systems Engineering
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    • v.6 no.2
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    • pp.143-159
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    • 2016
  • Cargo, such as a Tension Leg Platform (TLP), Semi-submersible platform (Semi), Spar or a circular Floating Production Storage and Offloading (FPSO), are frequently dry-transported on a Heavy Lift Vessel (HLV) from the point of construction to the point of installation. The voyage can span months and the overhanging portions of the hull can be subject to frequent wave slamming events in rough weather. Tie-downs or sea-fastening are usually provided to ensure the safety of the cargo during the voyage and to keep the extreme responses of the cargo, primarily for the installed equipment and facilities, within the design limits. The proper design of the tie-down is dependent on the accurate prediction of the wave slamming loads the cargo will experience during the voyage. This is a difficult task and model testing is a widely accepted and adopted method to obtain reliable sea-fastening loads and extreme accelerations. However, it is crucial to realize the difference in the inherent stiffness of the instrument that is used to measure the tri-axial sea fastening loads and the prototype design of the tie-downs. It is practically not possible to scale the tri-axial load measuring instrument stiffness to reflect the real tie-down stiffness during tests. A correlation method is required to systematically and consistently account for the stiffness differences and correct the measured results. Direct application of the measured load tends to be conservative and lead to over-design that can reflect on the overall cost and schedule of the project. The objective here is to employ the established correlation method to provide proper high-frequency responses to topsides and hull design teams. In addition, guidance for optimizing tie-down design to avoid damage to the installed equipment, facilities and structural members can be provided.

Experimental evaluation of the effects of cutting ring shape on cutter acting forces in a hard rock (커터 링의 형상에 따른 디스크커터 작용력의 실험적 평가)

  • Chang, Soo-Ho;Choi, Soon-Wook;Park, Young-Taek;Lee, Gyu-Phil;Bae, Gyu-Jin
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.15 no.3
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    • pp.225-235
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    • 2013
  • Cutter forces acting on a disc cutter in TBM are the key parameters for TBM design and its performance prediction. This study aimed to experimentally evaluate cutter forces with different ring shapes in a hard rock. The stiffness of a cutter ring was indirectly estimated from a series of full-scale linear cutting tests. From the experiments, it was verified that the rolling stress acting on a V-shape disc cutter was much higher than on a CCS disc cutter even though the penetration depth by a V-shape disc cutter could be increased in the same cutting condition. Finally, it is suggested that a prediction model considering the shape parameters of a disc cutter should be used for its better prediction.

Polypropylene Bundle Attached Multilayered Stigeoclonium Biofilms Cultivated in Untreated Sewage Generate High Biomass and Lipid Productivity

  • Kim, Byung-Hyuk;Kim, Dong-Ho;Choi, Jung-Woon;Kang, Zion;Cho, Dae-Hyun;Kim, Ji-Young;Oh, Hee-Mock;Kim, Hee-Sik
    • Journal of Microbiology and Biotechnology
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    • v.25 no.9
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    • pp.1547-1554
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    • 2015
  • The potential of microalgae biofuel has not been realized because of the low productivity and high costs associated with the current cultivation systems. In this study, a new low-cost and transparent attachment material was tested for cultivation of a filamentous algal strain, Stigeoclonium sp., isolated from wastewater. Initially, the different materials tested for Stigeoclonium cultivation in untreated wastewater were nylon mesh, polyethylene mesh, polypropylene bundle (PB), polycarbonate plate, and viscose rayon. Among the materials tested, PB led to a firm attachment, high biomass (53.22 g/m2, dry cell weight), and total lipid yield (5.8 g/m2) with no perceivable change in FAME profile. The Stigeoclonium-dominated biofilm consisted of bacteria and extracellular polysaccharide, which helped in biofilm formation and for effective wastewater treatment (viz., removal efficiency of total nitrogen and total phosphorus corresponded to ~38% and ~90%, respectively). PB also demonstrated high yields under multilayered cultivation in a single reactor treating wastewater. Hence, this system has several advantages over traditional suspended and attached systems, with possibility of increasing areal productivity three times using Stigeoclonium sp. Therefore, multilayered attached growth algal cultivation systems seem to be the future cultivation model for large-scale biodiesel production and wastewater treatment.

Causality between climatic and soil factors on Italian ryegrass yield in paddy field via climate and soil big data

  • Kim, Moonju;Peng, Jing-Lun;Sung, Kyungil
    • Journal of Animal Science and Technology
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    • v.61 no.6
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    • pp.324-332
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    • 2019
  • This study aimed to identify the causality between climatic and soil variables affecting the yield of Italian ryegrass (Lolium multiflorum Lam., IRG) in the paddy field by constructing the pathways via structure equation model. The IRG data (n = 133) was collected from the National Agricultural Cooperative Federation (1992-2013). The climatic variables were accumulated temperature, growing days and precipitation amount from the weather information system of Korea Meteorological Administration, and soil variables were effective soil depth, slope, gravel content and drainage class as soil physical properties from the soil information system of Rural Development Administration. In general, IRG cultivation by the rice-rotation system in paddy field is important and unique in East Asia because it contributes to the increase of income by cultivating IRG during agricultural off-season. As a result, the seasonal effects of accumulated temperature and growing days of autumn and next spring were evident, furthermore, autumnal temperature and spring precipitation indirectly influenced yield through spring temperature. The effect of autumnal temperature, spring temperature, spring precipitation and soil physics factors were 0.62, 0.36, 0.23, and 0.16 in order (p < 0.05). Even though the relationship between soil physical and precipitation was not significant, it does not mean there was no association. Because the soil physical variables were categorical, their effects were weakly reflected even with scale adjustment by jitter transformation. We expected that this study could contribute to increasing IRG yield by presenting the causality of climatic and soil factors and could be extended to various factors.

An Experimental Study for Construction of Static Aerodynamics Database of KF-16 based on Design of Experiments (KF-16의 DOE기반 정적 공력 데이터베이스 구축을 위한 실험적 연구)

  • Jin, Hyeon;Shim, Ho-Joon;Lee, Don-Goo;Ahn, Jae-Myung;Choi, Han-Lim;Oh, Se-Yoon
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.43 no.5
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    • pp.422-431
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    • 2015
  • Wind tunnel testing to construct static aerodynamic database of KF-16 was conducted for preceding research of design of experiments in wind tunnel testing. The test model is KF-16 scaled 1/33 and it has horizontal tail, flaperon, and rudder. The experiments consist of one experiment for analyzing aerodynamic coefficients under whether or not horizontal tail is present and four experiments for analyzing aerodynamic coefficients of changes of deflection angle in control surface which are flap, flaperon, rudder, and horizontal tail. After conducting wind tunnel testing, the experimental results show that the control surface changes have a great effect on Aerodynamic characteristics.

An Establishment of Canard-Leading Edge Flap Scheduling Law Based on Experimental and Numerical Studies For the Aerodynamic Design of Canard Type Fighter Class Aircraft (카나드 형상 전투기급 항공기 공력설계를 위한 실험 및 수치해석적 카나드-앞전플랩 스케줄링 법칙 수립)

  • Chung, In-Jae;Kim, Sang-Jin
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.35 no.7
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    • pp.655-660
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    • 2007
  • A canard-leading edge flap deflection scheduling laws have been established to enhance the maneuverability of the canard type fighter class aircraft. These scheduling laws are the relation of canard-leading edge flap deflections and flight conditions to maximize the lift-drag ratio. For these purposes, the corrected supersonic panel method has been used to predict the lift-drag characteristics due to canard-leading edge flap deflections. In addition, the high speed wind tunnel test has been conducted with 1/20 scale model to validate the predicted scheduling laws. Good agreements have been obtained compared with the results of high speed wind tunnel test. Based on the results obtained from the experimental and numerical studies, the corrected supersonic panel method has shown to be useful to establish the canard-leading edge flap deflection scheduling law for the aerodynamic design of canard type fighter class aircraft.

Relative Efficiency and Productivity Change of the Korean Non-Life Insurance Firms (국내 손해보험회사의 상대적 효율성 및 생산성 변화)

  • Kang, Ho-Jung
    • The Journal of the Korea Contents Association
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    • v.9 no.5
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    • pp.224-229
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    • 2009
  • This study measures the relative efficiency and productivity change of the Korean Non-Life Insurance Firms using DEA model and Malmquist Index for 2004-2007. The main results of this study can by summarized as follows. First, in case of efficiency of CCR for 2004-2007, the number of efficient firms(CCR value is one) are one firm, one firm, one firm, one firm respectively. Second, in case of efficiency of BCC for 2004-2007, the number of efficient firms(BCC value is one) are five firms, five firms, six firms, six firms respectively. Third, In case of return to scale for 2004-2007, DRS are five firms, DRS are five firms, DRS are six firms, DRS are six firms respectively, Fourth, Malmquist Index representing productivity change for 2004-2007 are 0.99 in 2004-2005, 1.04 in 2005-2006, 1.06 in 2006-2007.

The relationship between hostility and obsessive-compulsive symptoms: Focused on the moderating effect of impulsivity (적대성과 강박증상과의 관계: 충동성의 조절역할을 중심으로)

  • Choi, Hyera
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.1
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    • pp.368-378
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    • 2018
  • This study examined the relationship between hostility and obsessive-compulsive symptoms to clarify the differential role of overt hostility and covert hostility on obsessive-compulsive symptoms. In addition, this study examined whether impulsivity has a moderating effect on the relationship between hostility measures and obsessive-compulsive symptoms. The Buss Durkee Hostility Inventory (BDHI), Revised Obsessive Compulsive Inventory (OCI-R), and Barratt Impulsivity Scale (BIS) were used to measure hostility, obsessive-compulsive symptoms, and impulsivity, respectively. Data were collected from 150 online university students and analyzed using the correlation and moderated multiple regression model. The result showed that overt hostility was positively correlated with obsessive thoughts; covert hostility was positively correlated with obsessive thoughts and compulsive behavior. In addition, the regression results, which set the hostility variables as the predicting variable, revealed covert hostility to increase obsessive thinking and compulsive behavior, whereas overt hostility had no significant effect on both variables. Impulsivity was found to function as a moderator in the prediction of covert hostility on obsessive thought. With the result, the implications and limitations of this study are discussed.

An Analysis of the Impacts of School Library on Student's Learning (학교도서관의 교육적 효과에 관한 이론적 고찰)

  • Kwon, Eun-Kyung
    • Journal of Korean Library and Information Science Society
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    • v.40 no.1
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    • pp.451-469
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    • 2009
  • This paper analyzed four large scale studies on the impact of school libraries on students' learning. It identifies how students benefit from their school libraries and how the libraries contribute to the educational goals of the schools. The four studies were the 'National Power' project study, the Scotland study, the Ohio study, and the Delaware study. These studies developed frameworks for evaluating the impact of school libraries on learning, which give insights on how educational objectives and experiences are related with each other and what indicators are available to measure their impact on learning. Basing on Bloom's Taxonomy of educational objectives and Kuhlthau's model of information search process, the educational objectives of the frameworks included cognitive, affective, and psychomotor/physical domain, plus interpersonal domain. The four studies used such research methods as case studies, observations, interviews, focus group discussions, log data analyses in order to identify various learning experiences and impacts.

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