• Title/Summary/Keyword: core group

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Analysis of Fuel Options in TRIGA Reactor

  • Lee, Un-Chul;Lee, Chang-Kun;Lee, Ji-Bok;Kim, Jin-Soo;Lee, Sang-Kun;Jun, Byung-Jin;Chung, Bub-Dong
    • Nuclear Engineering and Technology
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    • v.11 no.1
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    • pp.29-45
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    • 1979
  • In this paper. nuclear characteristics of TRIGA Mark-III has been analyzed in detail for six different fuel options. Presently, 70 w/o enriched FLIP fuels are adopted for TRIGA core to improve fuel lifetime. However, such highly enriched fuels are not easily obtained due to nonproliferation treaty. This research examines the possible substitution for FLIP fuels with high density fuels without reducing the nuclear performance. This work will provide long-time plan for TRIGA operation.

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The Effect of Servitization of Business Groups on Management Performance (기업집단의 서비스화가 경영성과에 미치는 영향)

  • Lee, Jaehoon;Kim, Daecheol
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.45 no.3
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    • pp.204-213
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    • 2022
  • Most of the prior studies on the servitization of manufacturing companies have been actively studied, focusing on the performance and cases of servitization at the single company level. According to the results, most of the servitization at the single company level has been expanded based on the relevance of the company's core products. However, the form of companies that form a large axis of the Korean economy is a large-scale business group, and these business groups incorporate service affiliates for various purposes, so they show different characteristics from that of a single corporate. In addition, since the purpose of forming a business group is different for each business group, the service relevance between affiliates within the business group is different. Therefore, this study aims to examine the effect of service relevance between affiliates within a business group on the management performance of each business group. To this end, an empirical analysis will be conducted using panel data for 10 years from 2011 to 2020 for a total of 98 affiliates listed on KOSPI and KOSDAQ of 9 domestic business groups. Based on these results, the direction for improving management performance and establishing future servitization strategies for large business groups in Korea will be expected to be made.

Calculation of Nuclear Characteristics of the TRIGA Mark-III Reactor (TRIGA Mark-III 원자로의 노심특성계산)

  • Chong Chul Yook;Gee Yang Han;Byung Jin Jun;Ji Bok Lee;Chang Kun Lee
    • Nuclear Engineering and Technology
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    • v.13 no.4
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    • pp.264-276
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    • 1981
  • A simulation procedure which can represent time-dependent nuclear characteristics of TRIGA Mark-III reactor is developed. CITATION, a multi-group diffusion-depletion program, has been utilized as calculational tool. The group structure employed in this study consists of 7 groups: -3-fast and 4-thermal-which is conventionally utilized in TRIGA type reactor analysis. Three-dimensional nuclear characteristics are synthesized by combining results from two-dimensional plane calculation and two-dimensional cylinder calculation, since direct three-dimensional approach is not yet possible. An effort ia made to develope a method which can extract effective zone and group dependent bucklings by neutron diffusion theory rather than conventional zone and/or group independent Ducklings by neutron transport theory, since neutron leakage is quite high for small core such as research reactors. It is turned out that the method developed in this study gives satisfactory results. The calculation is performed under assumptions that all control rods are fully withdrawn, that no samples are inserted in the irradiation holes and that the core is located in the center of the reactor pool. Burnup-dependent variation of core excess reactivity, time dependent change of Xe-135 poisoning and reactivity worth of rotary specimen rack are calculated and compared with operation records. Neutron flux and power distribution as well as neutron spectrum in each irradiation .facility are presented.

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A Study on the Core Competency of Dance Festival Using VRIO Model (VRIO모델 분석을 활용한 춤 축제 핵심역량 도출)

  • Kwak, Ji-Hye
    • Journal of Korea Entertainment Industry Association
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    • v.13 no.8
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    • pp.77-91
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    • 2019
  • As of 2019, a report by the Ministry of Culture, Sports and Tourism showed that 884 diverse regional festivals are being held in the country. While there are successful festivals with large audience numbers and local economic effects, there are many festivals that only waste local budgets. Against this backdrop, the question of this study is "What are the key competences of a successful dance festival utilizing the VRIO model?" The development process and success factors of the success dance festival at home and abroad were analyzed in order to explore the key competences and specialization measures of the festival that our dance festival can take off as a successful dance festival. The purpose of the study is to examine what is the source of competitiveness of the regional festival through VRIO model, which can identify the key competencies of the festival to grow into a successful dance festival, and to derive the key competencies of the festival through the interview of the expert group(Focus Group Interview) to apply the development measures of our country's dance festival. According to the analysis, festival experts view the success factors of local festivals from various perspectives based on their empirical knowledge. The key competencies priority was 1. Theme, 2. the festival organization and professional personnel management, 3. The results came in the order of residents' participation. And the successful domestic and foreign dance festivals had their own core competencies. Growing up as a successful festival through festival management, which is worth no other festival, difficult to emulate, rare and difficult to replace, is seen as the biggest key to leading the regional festival to the world festival.

A study on an efficient prediction of welding deformation for T-joint laser welding of sandwich panel Part II : Proposal of a method to use shell element model

  • Kim, Jae Woong;Jang, Beom Seon;Kang, Sung Wook
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.6 no.2
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    • pp.245-256
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    • 2014
  • I-core sandwich panel that has been used more widely is assembled using high power $CO_2$ laser welding. Kim et al. (2013) proposed a circular cone type heat source model for the T-joint laser welding between face plate and core. It can cover the negative defocus which is commonly adopted in T-joint laser welding to provide deeper penetration. In part I, a volumetric heat source model is proposed and it is verified thorough a comparison of melting zone on the cross section with experiment results. The proposed model can be used for heat transfer analysis and thermal elasto-plastic analysis to predict welding deformation that occurs during laser welding. In terms of computational time, since the thermal elasto-plastic analysis using 3D solid elements is quite time consuming, shell element model with multi-layers have been employed instead. However, the conventional layered approach is not appropriate for the application of heat load at T-Joint. This paper, Part II, suggests a new method to arrange different number of layers for face plate and core in order to impose heat load only to the face plate.

Ballistic Match Analysis for 5.56 MM Bullet with New Copper Core Material (5.56밀리 소화기탄 탄자 코어 재질 변경에 따른 동심탄의 탄도호환성 분석)

  • Ko, Yongsin;Park, Yongdeok
    • Journal of the Korea Institute of Military Science and Technology
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    • v.19 no.6
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    • pp.712-720
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    • 2016
  • The purpose of this study was to inspect ballistic match of copper bullet at 4 points by analyzing vertical deviation about shot group of the 5.56 mm common bullets and copper bullets. The 5.56 mm bullet with new copper core material was developed for mitigation of environmental pollution and harmfulness to human body. The results of this study are as follows; using the regression analysis, estimated reference value of ballistic match were 51.6 mm, 64.9 mm, 87.3 mm and 99.6 mm at 25 m, 100 m, 200 m and 250 m range respectively. When analyzing the shooting test data, alternative hypothesis(The vertical deviations are less than the reference value) was adopted as the result of analyzing data using t-test. And the values of data through tool(PRODAS) and standard trajectory equation meet requirements of estimated ballistic match respectively. In conclusion, the level of ballistic match of 5.56 mm copper bullets meets the estimated reference level through regression analysis at 4 points.

Survey for Technology Forecasting for Crop Production using Delphi Method (경종작물분야의 델파이 기술예측조사)

  • Young-Am Chae
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.49 no.3
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    • pp.261-270
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    • 2004
  • The study was designed to forecast and derive future core technologies using Delphi method in Korea agriculture. Based on the technologies, agriculture in Korea will be expected to improve as a core and strategic industry producing high value added in 21 century. Questions were given to specialists by each technology in order to survey importance, realization time, level of R&D in Korea and the leading country, leading group of R&D, effective policy, etc. for each technology. The survey for Delphi was confined to the specialists in the area of crop production. The 44 core technologies were derived and 39 specialists answered the survey.

Dynamic Stability Effect of Applicable Core and Neuromuscular Training for 12 Weeks (12주간 적용 가능한 코어, 신경근 훈련의 동적 안정성 효과)

  • Kim, Kyoung-Hun;Lee, Sung-Cheol
    • Korean Journal of Applied Biomechanics
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    • v.20 no.1
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    • pp.101-108
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    • 2010
  • Recently, core and neuromuscular training(CNT) is emerging as a clinically relevant tool to improve neuromuscular control and to prevent sports injuries. The purpose of this study was to examine the effect of a 12 weeks CNT program on the dynamic stability after drop landing. The subjects attempted drop landing onto the force platform on single foot from a 40 cm height distance. The collected data was used to calculate the dynamic stability index. The Dynamic stability index was derived by measuring the medial-lateral stability index(MLSI), anterior-posterior stability index(APSI), and the vertical stability index(VSI). In comparison to the control group, the MLSI and APSI showed no difference, yet, it resulted in higher VSI. The results of this study suggest that CNT is worthwhile to be considered as a way to improve neuromuscular control and to prevent traumatic injuries. However, the results are taking into consideration to discuss the limitations of CNT and suggested future approaches.

A Study on Synthesis of Functional Composite Latex and Characteristics of Thermal Decomposition (기능성 복합 라텍스의 합성과 열분해 특성에 관한 연구)

  • Kwon, Jae-Beom;Kim, Nam-Suk;Lee, Nae-Woo;Seul, Soo-Duck
    • Journal of the Korean Society of Safety
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    • v.19 no.2
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    • pp.47-53
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    • 2004
  • Emulsion polymerization ws carried out using Alkyl methacrylate(RMA) like MMA, EMA, BMA and Styrene Monomer(SM) for core-shell latex preparation. It was synthesized at $80^{\circ}C$ in the presence of anionic surfactant SLS(Sodium Lauryl Sulfate). FT-IR and DSC analysis are used to confirm the synthesized core-shell emulsion latexes. Moreover DSC and TGA were used to investigate the thermal characterisitcs of them. The differences of the decomposition rate and the activation energy from TGA and DSC analysis are not so big. It considers that the pendent group is not affect of the thermal characteristics and stability on core-shell latexes, which is synthesized with RMA and Styrene. For investigating combustion products, LC50 values were calculated by FED(Fractional Effective Dose)from the Pyrolyzer-Mass sepctrometer.

A Study on Braking Performance of Break Disc (브레이크 디스크의 제동 성능에 관한 연구)

  • Ryu, Mi-Ra;Bae, Hui-Eun;Kim, Hyun-Su;Lee, Dae-Hee;Lee, Seong-Beom;Park, Jeong-Ho
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.12 no.3
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    • pp.13-20
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    • 2013
  • The present research aims to develop the aluminum disc brake replacing the existing cast iron disc brake. Material such as aluminum using FEM numerical analysis in order to improve the characteristics of each element, we analyze the performance characteristics and braking time you try to change. We try to lay the foundation for the development of an aluminum disc by investigating performance characteristics of the existing cast iron disc brake and comparing them with those of the aluminum disc. This involves FEM dynamics analysis for disc materials and experimental tests using the brake dynamometer. From this study, the results of 7075 aluminum braking performance can be seen that the best.