• Title/Summary/Keyword: stockpile

Search Result 61, Processing Time 0.027 seconds

Procedure for Rolling Plan of Stockpile via Value Assessment (가치평가방법(価値平価方法)을 통(通)한 비축(備蓄)의 연동계획 모형(模型))

  • Gang, Maeng-Gyu
    • Journal of Korean Institute of Industrial Engineers
    • /
    • v.10 no.2
    • /
    • pp.29-36
    • /
    • 1984
  • This paper proposes a procedure for solving a multi-stage stockpile problem with budget constant. To establish the stockpile importance index, value assessment procedure is employed with two attributes; item's essentiality and Unsatisfactoriness rate of requirements, Then we propose the balancing of stockpile importance index among stockpile items as a reasonable objective for stockpile problem.

  • PDF

A Case Study on the Reliability Assessment of Stockpile Ammunition (저장탄약의 품목별 신뢰도평가 사례 연구)

  • Yoon, Keun-Sig;Lee, Jong-Chan
    • Journal of Korean Society for Quality Management
    • /
    • v.40 no.3
    • /
    • pp.259-269
    • /
    • 2012
  • Purpose: The purpose of this study was to find out that the statistical method of stockpile reliability of ammunition by items can be applied to the reliability assessment of stockpile ammunition. Methods: We reviewed the statistical method of stockpile reliability of ammunition by items and verified the possibility of its application by case study. Results: We found that the statistical method of stockpile reliability of ammunition by items is very useful and effective to present the reliability of ammunition based on each item and to predict the change of the reliability in the future. The reliability of proximity fuse was about 94.5% and was influenced by manufacture's year and the difference between lot and lot more than storage period. Conclusion: The statistical method of stockpile reliability of ammunition by items can be applied to the reliability assessment of various stockpile ammunitions such as ammunition for mortar and canon.

Numerical Study on the Effects of Surface-Inhibitors for the Prevention of Spontaneous Combustion of the Coal Stockpile

  • Kim, Jae-Kwan;Park, Seok-Un;Jang, Ji-Hoon;Joo, Yong-Jin
    • KEPCO Journal on Electric Power and Energy
    • /
    • v.6 no.3
    • /
    • pp.289-296
    • /
    • 2020
  • In this paper, the effects of the spontaneous combustion inhibitor on the surface of the coal stockpile in the coal yard was investigated by numerical analysis. First, the numerical analysis method of the present study was compared with the results of the previous study by analyzing the case in which the spontaneous combustion inhibitor was not applied, while the effects of spraying the spontaneous combustion inhibitor for the prevention of spontaneous combustion onto various areas and positions was also analyzed. As a result, the larger the application area of the spontaneous combustion inhibitor, then the more effective it is for preventing spontaneous combustion as it blocks the oxygen inflow into the coal stockpile, while, when spraying the spontaneous combustion inhibitor from the bottom of the coal stockpile, then the greater the effect it has on the prevention of spontaneous combustion. In conclusion, it was most effective to spray the spontaneous combustion inhibitor from the bottom of the coal stockpile up to about 30% of the height of the coal stockpile, when considering the economic aspect.

Numerical Study on Spontaneous Combustion in Coal Stockpile (저탄장에서의 석탄 자연발화에 관한 수치 해석적 연구)

  • HONG, JINPYO;KIM, JAEKWAN;CHI, JUNHWA;PARK, SUKWOON;SEO, DONGGYUN;LEE, JINHYANG
    • Transactions of the Korean hydrogen and new energy society
    • /
    • v.28 no.6
    • /
    • pp.721-728
    • /
    • 2017
  • In this work, an one-dimensional analysis on spontaneous combustion in a coal stockpile was conducted using a commercial software $gPROMS^{(R)}$ based on assumption suggested by Arioy and Akgun. According to them, it is assumed that there is temperature difference between the surface of coal particle and the gas surrounded around the particle, and it is also assumed that the velocity of the gas is constant and thus oxygen is fed to the stockpile with same velocity. The higher temperature zone is formed to the surface of the coal stockpile at the initial phase and it became deepen as time is taken. Finally it was found that the temperature difference between coal particle and the gas was calculated as $57^{\circ}C$ and spontaneous combustion have not been occurred during 6 months since coal was piled in the stock.

A Study on the Development of ASRP for Improvement of the Stockpile Ammunition Reliability (저장탄약 신뢰성 향상을 위한 ASRP 발전방안 연구)

  • Choi, Seok-Cheol;Bae, Yun-Ho;Kim, Dong-Eok
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.8 no.4 s.23
    • /
    • pp.32-40
    • /
    • 2005
  • The ASRP(Ammunition Stockpile Reliability Program) is a overall evaluation system of ammunitions to improve the combat strength, having a short history. The storage lifetime of ammunitions, more than 20 years since being produced, differs according to storage circumstance and period. And it shows the different reliability for munitions. Because most ammunitions in military have been stored for a long time, these ammunitions need to be evaluated to maintain Serviceability, Reliability, Safety and Performance for the use of military. In this paper, it suggested the need to develop the techniques for ourselves, to make more laboratories for surveillance and testing and to extend research funds & concerns.

Study on Improving Learning Speed of Artificial Neural Network Model for Ammunition Stockpile Reliability Classification (저장탄약 신뢰성분류 인공신경망모델의 학습속도 향상에 관한 연구)

  • Lee, Dong-Nyok;Yoon, Keun-Sig;Noh, Yoo-Chan
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.21 no.6
    • /
    • pp.374-382
    • /
    • 2020
  • The purpose of this study is to improve the learning speed of an ammunition stockpile reliability classification artificial neural network model by proposing a normalization method that reduces the number of input variables based on the characteristic of Ammunition Stockpile Reliability Program (ASRP) data without loss of classification performance. Ammunition's performance requirements are specified in the Korea Defense Specification (KDS) and Ammunition Stockpile reliability Test Procedure (ASTP). Based on the characteristic of the ASRP data, input variables can be normalized to estimate the lot percent nonconforming or failure rate. To maintain the unitary hypercube condition of the input variables, min-max normalization method is also used. Area Under the ROC Curve (AUC) of general min-max normalization and proposed 2-step normalization is over 0.95 and speed-up for marching learning based on ASRP field data is improved 1.74 ~ 1.99 times depending on the numbers of training data and of hidden layer's node.

(Study of Hybrid Defense Simulation Model for Wartime Stockpile Requirement of K-9 Artillery Munition Against Armored Vehicle) (K-9 포탄 전시 소요량 산정을 위한 하이브리드 국방 시뮬레이션 모형에 관한 연구)

  • Cho, Hong-Yong;Chung, Byeong-Hee
    • Journal of the military operations research society of Korea
    • /
    • v.35 no.1
    • /
    • pp.1-19
    • /
    • 2009
  • This study aims to improve methodology for a Defense Simulation which is to calculate wartime stockpile requirement of artillery munitions for K-9 against armored vehicles. Due to incorrect data input and distortion in simulation logic, the expected occupancy ratio for each weapon system obtained from applying a traditional method using an analytical Defense Simulation shows considerable discrepancies from what we expect from a war in the future. This study analyzes causes for incorrect data input and phenomena of distortion in simulation logic. By taking measures to control these phenomena, the study aims to present trustworthy methodology for a Hybrid Defense Simulation which is to calculate wartime stockpile requirement of munitions for ground forces by interaction between a controlled training Defense Simulation model and a analytical Defense Simulation model

A Study of the stockpile and mobilization framework for the disaster management resources (재난관리자원 비축 및 동원 체계 연구)

  • Lee, Changyeol;Kim, Taehwan;Park, Giljoo
    • Journal of the Society of Disaster Information
    • /
    • v.11 no.3
    • /
    • pp.376-384
    • /
    • 2015
  • It needs a framework to minimizing the damage using the just-time just-resources strategy. But it is not easy to put 'what kinds of resources', 'how many resources', 'from where institutions', and 'how much money for the reimbursement'. So most of the local government depends on the field manager. In this study, we analysed the conventional system and provides the efficient methodology to the stockpiling and mobilizing against to the disaster. The study does not provide the stockpile amount for the local governments, because the stockpile amounts must consider the local diverse situations.

Numerical Study on the Effects of Surface-inhibitors on the Spontaneous Ignition of Coal Stockpile (저탄장 자연발화에 미치는 표면차단제 영향에 관한 수치 해석적 연구)

  • Kim, Jae-Kwan;Park, Seok-Un;Shin, Dong-ik
    • Fire Science and Engineering
    • /
    • v.33 no.2
    • /
    • pp.20-29
    • /
    • 2019
  • In this paper, the effect of spontaneous combustion inhibitor on the surface of coal stockpile in coal yard was investigated by numerical analysis. First, the numerical analysis method of the present study was compared with the results of the previous study by analyzing the case where the spontaneous combustion inhibitor was not applied, and the effect of preventing spontaneous combustion by various areas and positions for spraying spontaneous combustion inhibitor was analyzed. As a result, the larger the application area of the spontaneous combustion inhibitor, the more the effect of preventing spontaneous combustion by blocking the oxygen inflow into the coal stockpile, and the greater the effect of the spontaneous combustion prevention when spraying spontaneous combustion inhibitor from the bottom of the coal stockpile. Spontaneous combustion inhibitor should be sprayed effectively, considering the economic aspects, such as manufacturing cost etc.

A Case Study of Six Sigma for Improving Non-Function Test Process in the Ammunition Stockpile Reliability Program (저장탄약신뢰성평가의 비기능시험 업무프로세스 개선을 이한 6시그마 적용 사례 연구)

  • Yoon, Keun-Sig;Kim, Yong-Hwa;Bong, Ha-Gyu;Lee, Jong-Chan
    • Journal of Korean Society for Quality Management
    • /
    • v.34 no.4
    • /
    • pp.13-21
    • /
    • 2006
  • This paper includes an example of applying Six Sigma to Non-function test process to improve the efficiency and reliability of the Ammunition Stockpile Reliability Program (ASRP). By applying the DMAIC which is one of the Six sigma methods. we found out the vital few and as an improved version : effective redesign of check-sheets, pre-examination of technology, on-the-scene support system. As a result, we could enhance the reliability and reduce manpower and additional expenses.