• Title/Summary/Keyword: safety stock

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Performance based assessment for existing residential buildings in Lake Van basin and seismicity of the region

  • Isik, Ercan;Kutanis, Mustafa
    • Earthquakes and Structures
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    • v.9 no.4
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    • pp.893-910
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    • 2015
  • Earthquake safety of existing buildings has gained considerable importance after earthquakes which have occurred in our country especially in the last 30 years. Performance based assessment methods have been widely used for existing reinforced concrete structures. This study aims to investigate the earthquake performances of the building stock located in Van Lake basin in Eastern Anatolia of Turkey. The case study of buildings has been modeled on and the structural performances have been determined by employing the non-linear methods described in the latest Turkish Earthquake Code published in 2007. The Van lake basin is located on the very seismically active in a region. On October 23, 2011, a magnitude of Mw 7.2 earthquake struck the Van province in eastern Turkey. The earthquake ground motion was recorded as about 0.1g in Bitlis province. Performance evaluations have been performed by taking samples from each district consisting urban building stocks of Bitlis. A total of 16 reinforced concrete buildings have been evaluated. Among them, 53% of those buildings were determined in the Fully Operational performance level; 13% of them in the Life Safety performance and 34% of them could not be evaluated because of the ratio of the effective mass of first mode to the total mass of the buildings was smaller than 0.70. Therefore, incremental equivalent seismic load methods, which are a part of Turkish Earthquake Code -2007, cannot be used.

A study on the Method to Determine Optimal Service Level of a Distribution Center in Supply Chain Management Environment (SCM환경에서의 물류센터의 최적 서비스 수준 결정 방법)

  • 조용욱;박명규
    • Journal of the Korea Safety Management & Science
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    • v.3 no.3
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    • pp.55-64
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    • 2001
  • The main objective of this research is to develop a model to select the optimal input service level for a distribution center-multi branch inventory distribution system. With the continuous review policy, the distribution center places an order for specific order quantity to an outside supplier, and the order quantity is replenished after a certain lead time Also, each branch places an order for particular order quantity to the distribution center to satisfy the customer demands, and receives the replenishment after a lead time. When an out of stock condition occurs during an order cycle, a backorder is placed to the upper level to fill the unfilled demands. With these situation, variable demand and variable lead time are used for better industrial practice. Further, actual lead times with a generic lead time distribution are used in developing the control model. Under the actual lead time model, the customer service measures actually attained for the distribution center and each branch are explained as the effective customer service measures. Thus, throughout the optimal control (using computer search procedures), we can select the optimal input service levels for the distribution center and each branch to attain the effective service levels for each branch which is consistent with the goal level of service for each branch. At the same time, the entire distribution system keeps minimum inventories.

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Dynamic Behavior Evaluation for Split PC sleeper using the Field Test (현장측정을 통한 기존 분기기용 목침목과 개량 분기기 부절침목의 동적거동 비교평가)

  • Um, Hwan-Ju;Lee, Chang-Hun;Eum, Ki-Young
    • Journal of the Korean Society for Railway
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    • v.9 no.6 s.37
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    • pp.746-752
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    • 2006
  • The major objective of this study is to investigate the dynamic behavior evaluation of split PC sleepers for railway turnout by the field test. In railway engineering, a turnout is necessary to allow a vehicle to move from one track to another. So, turnout is required very complex railway technologies such as lolling stock, track. In reference to conventional line speed-up and improvement railway, accurate assembly of turnout affects travel ins qualify of turnout area and running safety. Because of heavy weight and a large volume of the long sleeper used to turnout and car limit, transport and the prerequisite for trouble-free transport of the factory pre-assembled major turnout components is achieved through division of long sleepers. The one of the advantages for using a split sleeper is to reduce the dynamic vibration according to the information of developed nations. Therefore, we investigate the characteristic of dynamic behaviors of split sleepers which are adopted for the first time to improve performance of turnout From the field test results of the split sleeper, it is evaluated that the modification of weight, material and stiffness compared with wood sleeper is very effective for the ballast safety. However, the decrease in vibration of split sleeper was not found out.

Noise Prediction Based on Analysis of Noise Measured Near the Turnout System of Existing Railroad

  • Eum, Ki-Young
    • The Journal of the Acoustical Society of Korea
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    • v.28 no.1E
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    • pp.23-28
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    • 2009
  • At the crossings of turnout systems, noise is generated by the impact of train on the connection points. However, rapid movement changes between rail and wheels on connection point are inevitable on existing turnout section which may cause safety concern as well as noise problem caused by repeated impact load by passing train. And given the turnout is a complicated system which combines various functions such as rolling stock, trackbed, signaling, communication and electrical system, it's very difficult to expect to improve the overall performance of the turnout in such a way of optimizing only particular part of such integrated system. Since the turnout is the only movable section among the integrated parts and has complicated structure that inevitably brings about quick and sudden movement, safety has been still put on the top of the list. This study was aimed at comparing and analyzing the noise data obtained around the turnout of existing railway, by categorizing them into tilting train, high speed train and traditional train, and by distance, speed and type of turnout. And based on the data measured, the forecast of noise level when tilting train accelerates around a turnout was conducted in the study.

Study on Medicine Related Policies for Management Strategies and Performances of the Pharmaceutical Industry (제약산업의 경영전략, 경영성과에 의약품관련정책이 미치는 영향에 관한 연구)

  • Jung, Jae-Hoon;Cho, Duk-Young;Choi, Suhe-yong
    • The Korean Journal of Health Service Management
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    • v.9 no.4
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    • pp.157-169
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    • 2015
  • Objectives : The aim of this study was to investigate the effect of various Republic of Korea policies, including the medicine cost rationalization policy implemented By investigating the management strategy/performance changes of the industry caused by such policies. Methods : Pharmaceutical companies listed on the national stock exchange and the KOSDAQ were examined for 10 years from 2004 to 2013. Their financial statements were collected and market changes before and after drug price policy implementations were compared. Results : From the result of this research, among the medicine related policies, the drug price rationalization policy was found to have a significant effect on business management strategies in terms of safety, profitability and growth potential after its implementation. After the drug pricing transparency policy was implemented, management strategies were affected significantly in terms of safety and profitability. Conclusions : As a result, all of the medicine related policies were found to have regulatory effects. Based on these findings, implications, research limitations and future study plans are presented.

Antiviral Efficacy of an Aquatic Disinfectant Tablet Composed to Calcium Hypochlorite Against Red Sea Bream Iridovirus

  • Cha, Chun-Nam;Lee, Yeo-Eun;Kang, In-Jin;Yoo, Chang-Yeul;Park, Eun-Kee;Kim, Suk;Lee, Hu-Jang
    • Journal of Food Hygiene and Safety
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    • v.27 no.3
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    • pp.285-289
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    • 2012
  • In this study, the veridical efficacy of an aquatic disinfectant tablet composed to calcium hypochlorite against red sea bream iridovirus (RBIV). A veridical efficacy was determined with the viability of RBIV contacted with the disinfectant in viral stock cultured in fat head minnow cell line. An aquatic disinfectant tablet and RBIV were reacted on the distilled water (DW), hard water (HW) or organic matter suspension (OM) condition. On DW and HW condition, RBIV was inactivated with 25,000 fold dilutions of an aquatic disinfectant tablet. With the investigation of the antiviral effect of the disinfectant on OM condition, RBIV was inactivated on 22,000 fold dilutions of an aquatic disinfectant tablet. As an aquatic disinfectant tablet possesses veridical efficacy against RBIV, the disinfectant solution can be used to limit the spread of cultured marine fish viral disease.

The Development of the Optimization Cutting Model for the H-Beam Steel (H형(形) 강(鋼) 제품(製品)의 절단(切斷) 모델 최적화(最適化)에 관한 연구(硏究))

  • Nam, Ho-Ki;Park, Sang-Min;Joh, Jong-Nam;Kim, Jhong-Hyun
    • Journal of the Korea Safety Management & Science
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    • v.13 no.4
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    • pp.213-223
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    • 2011
  • Recent cross-country competition and Chinese steel industry because of the emerging steel industry in Korea is a very difficult situation. Therefore, the steel industry in order to overcome this difficult market environment, the quality, cost competitiveness, enhance customer service levels and enhance international competitiveness through is needed. In this study, the purpose of strengthening the competitiveness of steel companies in order and hit the recovery of raw materials have been developed to optimize the model, developed before and after the results were analyzed. In addition, when applied to other products in order to minimize risk and optimize cutting trial stage of development details of the model is presented in detail. Therefore, the developed model was applied to order the recovery of raw materials hits and significantly improved production planning time has been shortened dramatically. In the present study the contents of other products when properly applied and the competitiveness of companies to improve customer service levels are expected to be helpful.

An Experimental Study on Operation Setting Optimization of Circuit Breaker for Improving Safety on DC Railroad Feeder System (직류철도 급전계통의 안전성 향상을 위한 차단기 동작 최적 설정의 실험적 고찰)

  • Lee, Jae-Bong;Jung, No-Geon;Kim, Jae-Moon
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.65 no.3
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    • pp.526-531
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    • 2016
  • This paper presents an experimental study on the optimal settings for the selected DC fault relay (50F) to improve the operating performance for the high-speed circuit breaker on DC feeding system which ensure safety within rolling stock maintenance depot. In this study, current supplied to overhead contact wire was calculated on 1 ms interval to analyze the correction values of DC fault selective relay for the operation of current supply cutout. Particularly, standards for the accurate detection of accidents between an electric railway vehicle and the electric power facilities are shown by investigating the optimal correction values for detection of fault current, and the results indicated that it takes about 213 ms for the DC fault selective relay(50F) to fully open. In the future, the correction values of DC fault selective relay suggested in this paper will be used as the reference values of protective relay for the safe operation of DC electric railroad system such as urban railway.

A Study on the Economics Evaluation using Weighted Average Cost of Capital (가중평균자본비용을 이용한 투자 안의 경제성평가에 관한 연구)

  • 김태성;구일섭
    • Journal of the Korea Safety Management & Science
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    • v.3 no.4
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    • pp.135-144
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    • 2001
  • The capital cost of the company is one that must be paid to the money owner as the price by using the money. The capital cost according to the source of money supply can be estimated by the expected profit rate undertaken by the use of the capital. But in the area of pre-existent economic evaluation, the evaluation of the company investment has been treated by the profit rate of the capital after considering the repayment conditions of the other's money or the interest. Thus in this study, in case the company makes an investment on various kinds of the capital at the same time, not make use of the capital as a one source, the economic evaluation of an investment should be handled by taking the weighted average cost of capital into consideration in proportion to the constitution of the capital cost by the sources of money supply, Especially, as the cost of the private money is very much connected with the profit rate through the stock market, the Capital Asset Pricing Model (CAPM) will be applied. This kind of economic evaluation method can be said to have much to do with the Economic Value Added : EVA) as well as to be highly thought as a standard to estimate the company' value recently To certify the usefulness of this approach, the case study of the output of the capital cost will be made for the purse of the economic evaluation of the alternative investment by using the financial statements of a motor company H.

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Safety Assessment on Long-term Radiological Impact of the Improved KAERI Reference Disposal System (the KRS+)

  • Ju, Heejae;Kim, In-Young;Lee, Youn-Myoung;Kim, Jung-Woo;Hwang, Yongsoo;Choi, Heui-joo;Cho, Dong-Keun
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.18 no.spc
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    • pp.75-87
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    • 2020
  • The Korea Atomic Energy Research Institute (KAERI) has developed geological repository systems for the disposal of high-level wastes and spent nuclear fuels (SNFs) in South Korea. The purpose of the most recently developed system, the improved KAERI Reference Disposal System Plus (KRS+), is to dispose of all SNFs in Korea with improved disposal area efficiency. In this paper, a system-level safety assessment model for the KRS+ is presented with long-term assessment results. A system-level model is used to evaluate the overall performance of the disposal system rather than simulating a single component. Because a repository site in Korea has yet to be selected, a conceptual model is used to describe the proposed disposal system. Some uncertain parameters are incorporated into the model for the future site selection process. These parameters include options for a fractured pathway in a geosphere, parameters for radionuclide migration, and repository design dimensions. Two types of SNF, PULS7 from a pressurized water reactor and Canada Deuterium Uranium from a heavy water reactor, were selected as a reference inventory considering the future cumulative stock of SNFs in Korea. The highest peak radiological dose to a representative public was estimated to be 8.19×10-4 mSv·yr-1, primarily from 129I. The proposed KRS+ design is expected to have a high safety margin that is on the order of two times lower than the dose limit criterion of 0.1 mSv·yr-1.