• Title/Summary/Keyword: Break efficiency

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Urban Economic Regeneration Strategies of Local Initiative through the Analysis of Regional Strategic Industry Policy Cases (지역전략산업 육성 사례 분석을 통한 지역주도의 도시경제기반형 도시재생 추진 방안)

  • Ryu, Dong-Ju;Kim, Joo-Jin
    • Land and Housing Review
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    • v.7 no.4
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    • pp.239-249
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    • 2016
  • This study aims to find implications for urban economic regeneration strategies of local initiative by analyzing of promoting regional strategic industries, both Seongnam and Goyang in terms of regional industrial policy, institution and specialized service agency. The main results based on the case studies are as follows. First, It is a top priority to formulate the policy direction, such as selecting strategic industries and prepare means for improving it. It should keep reliability and continuity for inducing economic units. Second, It is necessary to consider the effectiveness and diversity of institutions. The institutions to be formalized by municipal ordinance and rules for making the successful implementing system of policies. It is necessary to implement strategic industry policy linked with the central government or public organizations for expanding of a diversity of policies. It is necessary to change in viewpoint on the deregulation and tax break for the private sectors as inducements to achieve the regional economy activation. Third, It is necessary to introduce the specialized service agency to improve an effectiveness and efficiency of institutions and accelerate a network within economic units.

The Effects of Alkaloid Fraction of Korean Ginseng on the Radiation-Induced DNA Strand Breaks (방사선 조사에 의한 DNA Double Strand Breaks의 생성 및 회복에 미치는 인삼 알칼로이드 분획의 효과)

  • Cho Chul Koo;Kim Tae Hwan;Yoo Seong Yul;Koh Kyoung Hwan;Kim Mi Sook;Kim Jeong Hee;Kim Seong Ho;Yoon Hyung Keun;Ji Young Hoon
    • Radiation Oncology Journal
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    • v.13 no.2
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    • pp.113-120
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    • 1995
  • Purpose : To investigate the effect of alkaloid fraction from Korean ginseng on radiation-induced DNA double strand breaks (dsb) formation and repair in murine lymphocytes Materials and Methods : We used the neutral filter elution technique to assay $^{60}Co\;{\gamma}$ ray-induced DNA double strand breaks formation and repair in C57BL/6 mouse spleen lymphocytes for evaluating the dose-response relationship in the presence of alkaloid fraction as a radioprotective agent. The lymphocytes were stimulated with Phytohemagglutinin (PHA, 2 u g/ml) to label $^3[H]-thymidine.$ Isotope-labelled lymphocytes in suspension were exposed to 100 Gy at $0^{\cdot}C$ in the alkaloid fraction-treated group and elution procedure was performed at PH 9.6. The extents of formation of radiation-induced DNA double strand breaks and repair were compared respectively via strand scission factor (SSF) and relative strand scission factor (RSSF). Results: Alkaloid fraction reduced the formation of double strand breaks with dose modification factor of 2 15, compared to control group Rejoining of DNA dsb appeared to take place via two components. The first fast component was completed within 20.4 minutes, but the second slow component was not completed until 220.2 minutes after irradiation. About $30\%$ of dsb formed by irradiation was ultimately unrejoined despite the administration of alkaloid fraction. The administration of alkaloid fraction had a great effect on the second slow component of repair; the half-time of fast component repair was not changed, but that of slow component was 621.8 minutes. Conclusion: Neutral filter elution assay Proved to be a very effective method to quantitate the extents of DNA dsb formation and its repair. By using this technique, we were able to evaluate the efficiency of alkaloid fraction from Korean ginseng as a valuable radioprotector. Alkaloid fraction can be used prophylactically to prevent or ameliorate the severe radiation damages in workers and neighbors around the atomic power plants. For more refined study, however, more advanced purification of alkaloid fraction wil be needed in the near future.

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Looking for an Adequate Methodology for the Korean Reservoir Using Canonical Correspondence Analysis (CCA를 통한 한국 호소 연구 방법론 탐색)

  • Chung, Sang-Ok;Jeon, Hyoung-Joo;Hong, Kwan-Eui;Kim, Jong-Hwa;Park, Young-Seuk
    • Korean Journal of Environment and Ecology
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    • v.20 no.4
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    • pp.365-373
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    • 2006
  • With a few exceptions, Korean lakes are artificially constructed for multi-purposes throughout the country. In the majority of cases, a lake is in a multiple series of reservoirs along a river or is an estuary Moreover, nutrient supplying activities (including sand extraction) and biomanipulation(esp., overfishing and fish introduction) are omnipresent in most cases. Furthermore, there is an Asian monsoon every year. In brief, europhication and algal blooms break out as a result of complicated causes. However limnological monitoring and scientific working programs are in the course of beginning. The question is what kind of strategy is desirable to establish a solid limnological database for the efficiency of the restoration process in each Korean reservoir We present light monitoring cases on the basis of algal and some physicochemical data in 2005. Do they give some useful informations despite their simplicity. Based on physicochemical factors and phytoplankton data using Utermohl method and Canonical Correspondence Analysis(CCA) were performed for Lake Cheongpyeong, Lake ASan, Lake Namyang, and Lake SapGyo. The results of CCA showed that Lake Cheongpyeong was different from the other three Lakes at estuary. Also each Lake at estuary was slightly different from one other. This result would encourage to initiate building an adequate Korean reservoir-ecosystem understanding and models for better ecological management despite the limited data. However, the results also indicate to sustain collecting ecological data and building database to interpret the Korean ecological reservoir model.

Melt Grafting of Citraconic Acid onto an Ethylene-Propylene-Diene Terpolymer (EPDM) -Effect of Reaction Conditions and Initiator Type on the Melt Grafting of Citraconic Acid onto EPDM- (EPDM고무와 씨트라코닉산의 melt grafting - 반응조건과 개시제에 따른 영향 연구 -)

  • Kim, Jung-Soo;Bae, Jong-Woo;Lee, Jin-Hyok;Oh, Sang-Taek;Kim, Gu-Ni;Lee, Young-Hee;Kim, Han-Do
    • Elastomers and Composites
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    • v.48 no.1
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    • pp.39-45
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    • 2013
  • Melt grafting of citraconic acid (CCA) onto an ethylene-propylene-diene terpolymer (EPDM) with various peroxide initiators was performed using a Haake Rheocorder. Finding the optimum running condition and concentration is critical for effective grafting and performance of grafted material. Therefore, this study focused on the effects of mixing (reaction) condition and monomer/initiator dosages on the grafting degree, grafting efficiency and crosslinking degree (gel content), melt flow index and mechanical properties of CCA-g-EPDM. As the grafting degree/crosslinking degrees increased, the tensile strength increased significantly, but elongation at break and melt flow index decreased. The initiator 2,5-dimethyl-2,5-di(tert-butyl peroxy)-hexane (T-101) appeared to meet for the best grafting(2.31%). The grafting degree increased markedly with increasing monomer CCA/initiator T-101 contents. The grafting degree also increased with increasing mixing temperature/time, and then leveled off or decreased/increased a little. The optimum monomer/initiator dosages and reaction temperature/time were found to be about 5/0.05 wt% and $180^{\circ}C$/15min, respectively.

A study on vulnerability analysis and incident response methodology based on the penetration test of the power plant's main control systems (발전소 주제어시스템 모의해킹을 통한 취약점 분석 및 침해사고 대응기법 연구)

  • Ko, Ho-Jun;Kim, Huy-Kang
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.24 no.2
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    • pp.295-310
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    • 2014
  • DCS (Distributed Control System), the main control system of power plants, is an automated system for enhancing operational efficiency by monitoring, tuning and real-time operation. DCS is becoming more intelligent and open systems as Information technology are evolving. In addition, there are a large amount of investment to enable proactive facility management, maintenance and risk management through the predictive diagnostics. However, new upcoming weaponized malware, such as Stuxnet designed for disrupting industrial control system(ICS), become new threat to the main control system of the power plant. Even though these systems are not connected with any other outside network. The main control systems used in the power plant usually have been used for more than 10 years. Also, this system requires the extremely high availability (rapid recovery and low failure frequency). Therefore, installing updates including security patches is not easy. Even more, in some cases, installing security updates can break the warranty by the vendor's policy. If DCS is exposed a potential vulnerability, serious concerns are to be expected. In this paper, we conduct the penetration test by using NESSUS, a general-purpose vulnerability scanner under the simulated environment configured with the Ovation version 1.5. From this result, we suggest a log analysis method to detect the security infringement and react the incident effectively.

Finite Element Analysis on the Strength Safety of a Fuel Tank for Highly Compressed Gas Vehicle (수술실 내의 아산화질소($N_2O$) 노출평가)

  • Baek, Jong-Bae;Uhm, Min-Yong
    • Journal of the Korean Institute of Gas
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    • v.13 no.6
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    • pp.34-38
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    • 2009
  • Nitrous oxide, which is used as an anesthetic gas, has been shown to be a chronic health hazard. It is necessary to monitor and control the nitrous oxide exposure of the operating theaters staff. In this study, N2O exposure level of the operating nurses is assessed with a GC-ECD. The nitrous oxide gas is collected on a molecular sieve 5A contained in a glass tube and desorbed for 12 hours at $100^{\circ}C$ in heating block. As a result of the test using GC-ECD, calibration curve's $R^2$ of $N_2O$ is 0.9992, LOD is $0.96{\mu}g$/injection, LOQ is $3.21{\mu}g$/injection, desorption efficiency is 94.78 4.50% in average and break through is within 10% compared with the concentration. The average concentration before operation is 5.12ppm and it is 42.3ppm during operation. There are a significant difference showing that the P value is lower than 0.05. Assessing exposure level to nitrous oxide based on nurses' working positions, the exposure levels do not show significant difference( P>0.005). And $N_2O$ in active sampling method is higher than passive sampling method(P<0.05).

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Causes of accidents and preventive measures due to defects in pump car booms (펌프카의 붐대 결함에 의한 사고원인과 방지대책)

  • Cho Choonhwan
    • Journal of the Korea Institute of Construction Safety
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    • v.6 no.1
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    • pp.7-11
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    • 2024
  • Pump car is an equipment that transports concrete products as needed to the place where they are poured. In order to pour a large amount of concrete in a short period of time, using a pump car is the most efficient in terms of economic efficiency and quality control. However, recently, many casualties have occurred due to boom damage during concrete pouring, so this study suggests that improvements are needed in the equipment manufacturing stage, inspection standards for old equipment, and equipment rental system. The reason is that, as a result of the finite element analysis of the pump car, the significant stress acting at the second stage of the boom and the maximum stress at the top of the boom were found to be 895.39 MPa, and M.S. Since it was evaluated the lowest at 0.04, the need for reinforcement was recognized. And it was confirmed that the 2nd stage boom was the most stressful and vulnerable part of the 1st to 5th stage booms. Therefore, it is necessary to increase the thickness and rigidity of members at the design and manufacturing stage, and to reinforce the steel plates of currently used equipment. In addition, it is urgent to establish a system that makes non-destructive testing mandatory for all general construction machinery and holds inspection agencies responsible for missing boom defects during non-destructive testing and regular inspections.

Study on Effect of Convection Current Aeration System on Mixing Characteristics and Water Quality of Reservoir (대류식 순환장치의 저수지수체 유동특성 및 수질영향)

  • Lee, Yo-Sang;Lee, Kwang-Man;Koh, Deok-Koo;Yum, Kyung-Taek
    • Korean Journal of Ecology and Environment
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    • v.42 no.1
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    • pp.85-94
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    • 2009
  • This study examines the operational effectiveness of a Convection Current Aeration System (CCAS) in reservoir. CCAS was run from June, 2008 when the thermocline begun forming in the reservoir. This paper reviews the influence of stratification, dissolved oxygen dynamics and temperature in the lake's natural state from June to October 2008. The survey was done on a week basis. Upwelling flow effects a radius of $7{\sim}10m$ at a surface directly and was irrelevant to the strength of thermocline. On the other hand, it was affected the number of working days, and strength of thermocline at vertical profiles of the reservoir. Longer CCAS run, the deeper was the vertical direct flow area. However it didn't break the thermocline during summer season of 2008. The operating efficiency of the CCAS in the reservoir depends on hydraulics and meteological conditions. Computational Fluid Dynamics (CFD) is a very useful tool for evaluating the operating efficiency of fluid dynamics. The geometry for CFD simulation consists of a cylindrical vessel 25 m radius and 40 m height. The CCAS is located in center of domain. The non-uniform tetrahedral meshes had a bulk of the geometry. The meshes ranged from the coarse to the very fine. This is attributed to the cold water flowing into the downcomer and rising, creating a horizontal flow to the top of the CCAS. The result of CFD demonstrate a closer agreement with surveyed data for temperature and flow velocity. Theoretical dispersion volume were calculated at 8m depth, 120 m diameter working for 30 days and 10 m depth, 130 m diameter working for 50 days.

Effects of Feed Protein Quality on the Protein Metabolism of Growing Pigs - Using a Simulation Model - (성장기 돼지의 단백질대사에 사료단백질의 질이 미치는 영향 -수치모델을 사용하여-)

  • 이옥희
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.26 no.4
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    • pp.704-713
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    • 1997
  • This study was conducted to describe qualitatively the protein metabolism of pigs during growth depending on the feed protein quality and to describe quantitatively amino acids requirements, using a simulation model. The used model has a non-linear structure. In the used model, the protein utilization system of a pig, which is in the non-steady-state, is described with 15 flux equations and 11 differential equations and is composed with two compartments. Protein deposition(g/day) of pigs on the 30th, 60th, 90th, and 120th day of feeding duration with three-quality protein, beginning with body weight 20kg, were calculated according to the empirical model, PAF(the product of amino acid functions) of Menke, and was used as object function for the simulation. The mean of relative difference between the simulated protein deposition and PAF calculated values, lied in a range of 8.8%. The simulated protein deposition showed different behavior according to feed protein quality. In the high-quality protein, it showed paraboloidal form with extending growth simulation up to 150eh day. So the maximum of protein deposition was acquired on the 105th day of simulate growth time and then it decreased fast. In the low-quality protein, this form of protein deposition in the course of simulated growth did not appear until 150th day. The simulated protein mass also showed a difference in accordance with feed protein quality. The difference was small on the 30th day of simulated growth, but with duration of the simulated growth it was larger. On the 150th day the simulated protein deposition of high quality protein was 1.5 times higher as compared to the low-quality protein. The simulated protein synthesis and break-down rates(g/day) in the whole body showed a parallel behavior in the course of growth, according to feed protein quality. It was found that the improvement of feed protein quality increased protein deposition in the whole body through a increase of both protein synthesis and breakdown during growth. Also protein deposition efficiency, which was calculated from simulated protein deposition and protein synthesis, showed a difference in dependence on the protein qualify of feed protein. The protein deposition efficiency was higher in pigs fed with high quality protein, especially at the simulation time 30th day. But this phenomena disappeared with growth, so on the 150th day of growth, the protein deposition of the high feed protein quality was lowest among the three different quality of feed protein. The simulated total requirement of the 10 essential amino acids for the growth of pigs was 28.1(g/100g protein), similar to NRC. The requirement of lysine was 4.2(g/100g protein).

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Development of a Business Model for Korean Insurance Companies with the Analysis of Fiduciary Relationship Persistency Rate (신뢰관계 유지율 분석을 통한 보험회사의 비즈니스 모델 개발)

  • 최인수;홍복안
    • Journal of the Korea Society of Computer and Information
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    • v.6 no.4
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    • pp.188-205
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    • 2001
  • Insurer's duty of declaration is based on reciprocity of principle of the highest good, and recently it is widely recognized in the British and American insurance circles. The conception of fiduciary relationship is no longer equity or the legal theory which is only confined to the nations with Anglo-American laws. Therefore, recognizing the fiduciary relationship as the essence of insurance contract, which is more closely related to public interest than any other fields. will serve an efficient measure to seek fair and reasonable relationship with contractor, and provide legal foundation which permits contractor to bring an action for damage against violation of insurer's duty of declaration. In the future, only when the fiduciary relationship is approved as the essence of insurance contract, the business performance and quality of insurance industry is expected to increase. Therefore, to keep well this fiduciary relationship, or increase the fiduciary relationship persistency rates seems to be the bottom line in the insurance industry. In this paper, we developed a fiduciary relationship maintenance ratio based on comparison by case, which is represented with usually maintained contract months to paid months, based on each contract of the basis point. In this paper we have developed a new business model seeking the maximum profit with low cost and high efficiency, management policy of putting its priority on its substantiality, as an improvement measure to break away from the vicious circle of high cost and low efficiency, and management policy of putting its priority on its external growth(expansion of market share).

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