• Title/Summary/Keyword: safety stock

Search Result 330, Processing Time 0.024 seconds

Biocontrol of root diseases of fruit trees with fungal viruses

  • Matsumoto, Naoyuki;Nakamura, Hitoshi;Ikeda, Kenichi;Arakawa, Masao;Uetake, Yukari
    • Proceedings of the Korean Society of Plant Pathology Conference
    • /
    • 2003.10a
    • /
    • pp.19-20
    • /
    • 2003
  • Helicobasidium mompa Tanaka and Resellinia necatrix Prillieux cause violet root rot and white root rot of various crops, respectively. Intensive cultural practices, such as the use of dwarf stock, glasshouse cultivation, etc., predispose plants to the diseases. The diseases can be controlled only by biennial drench of 50100L of chemicals for each tree. Biocontrol with soil microorganisms proved ineffective under field conditions. Long-term control may be hampered by the perennial growth of hosts and by the difficulty in the establishment of antagonists in soil. Crop rotation or soil amendment is not applicable, either. Fungal viruses with dsRNA genome (Buck 1986) are promising against root diseases of fruit trees since they exist within the cytoplasm of fungal hyphae and need no effort to help them persist in the field. The viruses are considered to spread though the network of fungal mycelia in the soil once they enter the fungal cytoplasm. Here, we present preliminary results from a project to control the root diseases of fruit trees with dsRNA.(중략)

  • PDF

A Study on Complication factors between foreign and domestic chefs (국내외 조리시간의 갈등요인에 관한 연구)

  • 최수근;조우제
    • Culinary science and hospitality research
    • /
    • v.6 no.3
    • /
    • pp.99-118
    • /
    • 2000
  • This study attempts to identify the level of conflicts occurring between foreign and domestic chefs, and to suggest the way of controlling those conflicts in order to well manage human resources, foreign chefs. Based on the empirical research, the research findings shows that in terms of targeting and achieving objectives different level of conflicts are experienced when age, hotel type, position varies. For example. purchasing excessive foreign foods may cause undesirable stock which will lead to considerable loss. In order to overcome this problem the advantages of the chain-operated and the independent hotel's food purchasing system must be incorporated. Secondly, another conflicts arise when the architecture and system of a kitchen is different from what foreign chefs are familiar with. Kitchen architecture and system should be well-designed in terms of delivery channel, sanitation, safety, food control, banquet etc.. In developing menu, chefs often have different criteria in the scale of sweet and salt of a particular dish. Foreign chefs often blame his subordinates for not meeting his requirements without proper training or education. Finally, because of the different culture, communication as well as the lack of mutual understanding problem occur. Even though today is called global town. some chefs do not seem to open their minds to learn other developing countries' culture. In diversity management aspect, chefs need to put much effort to be aware of other countries' culture, history, political and economic situation. In prior to employing foreign chefs, the job enrollment and description must be prepared so as to minimize the conflicts, which otherwise will create poor job performance.

  • PDF

A study on crash energy absorption design of passenger-car extreme structure of tilting train prototype (한국형 고속틸팅열차의 중간부 충돌에너지 흡수구조에 대한 연구)

  • Kwon T.S.;Jung H.S.;Koo J.S.
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2005.06a
    • /
    • pp.326-330
    • /
    • 2005
  • Crahworthy design of trains is now indispensable procedure in modern railway vehicle design for ensuring the safety of passengers and crew. It is now widely recognized that a more strategic approach is needed in order to absorb higher level energy in a controlled manner and minimize passenger injuries effectively. The first design step in this strategic approach is the design of the front end structure(so called HE extremities) to absorb a large part of total impact energy and then the structure of passengers non-accommodation zones(so called HE extremities) is designed to absorb the rest of impact energy. In this paper, the passengers entrance door area is selected as the LE(low energy) extremities and the design of the LEE was carried out. The main part of LEE design procedures is the design of energy absorbing tubes. For this purpose, the several tube candidates are introduced and compared to each others with numerical crash simulation.

  • PDF

Safety Security Method and Onboard Design for Inter-operation between CBTC, ATC Train Control System (CBTC, ATC 열차제어 시스템 간 상호운행을 위한 차상장치 설계 및 안전 확보 방안)

  • Lee, Jae-Ho;Oh, Sea-Hwa;Park, Jong-Moon;Lee, Key-Seo
    • The Journal of the Korea institute of electronic communication sciences
    • /
    • v.10 no.8
    • /
    • pp.875-882
    • /
    • 2015
  • Recently, An introduction of communication based train control system both into greenfield and brownfield of urban transit network has been actively reviewed. However, since a number of line sections and rolling stock depots tends to be constructed based on track circuit for various reasons, necessity of inter-operation between two distinct train control system (CBTC, ATC) increases. Therefore, we propose a design of on-board signalling device that allows inter-operation of CBTC and ATC lines and a method to secure safe connection between these two lines without derailing point machine.

A Study on Hybrid Track Circuit Tag Recognition Enhancement (하이브리드 궤도회로 태그 인식율 향상에 관한 연구)

  • Yang, Dong-In;Li, Chang-Long;Jin, Zhe-Huan;Lee, Key-Seo;Ko, Yun-Seok
    • The Journal of the Korea institute of electronic communication sciences
    • /
    • v.9 no.4
    • /
    • pp.537-542
    • /
    • 2014
  • Track circuit is a simple electrical device which lies in the connection of the two rails by the wheels and axle of locomotives and rolling stock to short out an electrical circuit, used to detect the absence of a train on rail tracks. In railway signaling system, there are similar systems such as RFID and wheel sensor, GPS etc, are research and developing. Hybrid track circuit is using RFID antenna and reader on the cab and RFID tag on the sleeper. because of the safety in railway operation, tag detection of train position detection function in the hybrid track circuit needs high reliability. This paper studied tag recognition enhancement used tag angles.

The Interface Scheme and Application Between Rolling Stock System and PSD (철도차량시스템과 PSD간 인터페이스 방안 및 적용 현황)

  • Lee Jong-Seong;Min Young-Ki;Kim Kyoung-Shik;Choi Jong-Mook
    • Proceedings of the KSR Conference
    • /
    • 2004.06a
    • /
    • pp.1510-1512
    • /
    • 2004
  • Platform Screen Door System is a facility on platform to separate platform from track, having automatic sliding door structures interlocked to opening and closing of train door with integrated control unit. When a train comes to a stop at a designed position at a station, onboard ATC/ATO system transmits train berth signal to wayside signaling system. In case of automatic/driverless operation, opening and closing of the Platform Screen Door will be controlled by wayside signaling system. Unfortunately, we often see the case in news that passengers fall into track and their contact with train lead to critical accidents. However, passengers will be free from such accidents on the platform with the Platform Screen Door System. Especially during the rush hours, to ensure passenger's safety and smooth getting on & off, it is necessary to arrange. some station staffs on the platform without the Platform Screen Door System. On the other hand, the Platform Screen Door System will realize such operation by fewer staffs. Due to the above reasons, the Platform Screen Door System is becoming more popular in subway system recently.

  • PDF

A Design for Integrated Logistics System with Inventory Control and Transportation Planning Problem (재고와 수송계획문제를 고려한 통합물류시스템 설계)

  • 우태희;조남호
    • Journal of Korean Society of Industrial and Systems Engineering
    • /
    • v.21 no.48
    • /
    • pp.37-52
    • /
    • 1998
  • In many distribution systems important cost reductions and/or service improvements may be achieved by adopting an efficient inventory policy and proper selection of facilities. These efficiency improvements and service enhancements clearly require an integrated approach towards various logistical planning functions. The areas of inventory control and transportation planning need to be closely coordinated. The purpose of this paper is to construct an integrated model that can minimize the total cost of the transportation and inventory systems between multiple origin and destination points, where in origin point i has the supply of commodities and in destination point j requires the commodities. In this case, demands of the destination points are assumed random variables which have a known probability distribution. Using the lot-size reorder-point policy and the safety stock level that minimize total cost we find optimal distribution centers which transport the commodities to the destination points and suggest an optimal inventory policy to the selected distribution center. We also show if a demand greater than one unit will occur at a particular time, we describe the approximate optional replenishment policy from computational results of this lot-size reorder-point policy. This model is formulated as a 0-1 nonlinear integer programming problem. To solve the problem, this paper proposes heuristic computational procedures and a computer program with UNIX C language. In the usefulness review, we show the meaning and validity of the proposed model and exhibit the results of a comparison between our approach and the traditional approach, respectively.

  • PDF

A Study on Determination of the Minimum Vertical Spring Stiffness of Track Pads in Korea High Speed Railway. (고속철도 궤도패드의 최소 수직 스프링계수 결정에 관한 연구)

  • Kim Jeong-il;Yang Sin-Chu;Kim Yun-Tae;Suh Sa-Bum
    • Proceedings of the KSR Conference
    • /
    • 2005.05a
    • /
    • pp.504-509
    • /
    • 2005
  • Railway noise and vibration has been recognized as major problems with the speed-up of rolling stock. As a kind of solution to these problems, the decrease of stiffness of track pad have been tried. However, in this case, overturning of rail due to lateral force should be considered because it can have effect on the safety of running train. Therefore, above two things - decrease of stiffness of track pad and overturning of rail due to lateral force - should be considered simultaneously for the appropriate determination of spring coefficient of track pad. With this viewpoint, minimum spring coefficient of track pad is estimated through the comparison between the theoretical relationship about the overturning of rail and 3-dimensional FE analysis result. Two kinds of Lateral force and wheel load are used as input loads. Extracted values from the conventional estimation formula and the Shinkansen design loads are used. It is found that the overturning of rail changes corresponding to the change of the stiffness of track pad and the ratio of lateral force to wheel load. Moreover, it is found that the analysis model can have influence on the results. Through these procedure, minimum spring coefficient of track pad is estimated.

  • PDF

A Study on Mobility Gradients and Phase Transitions in N-propyl-N,N-dimethylethanolamine Reaction (N-propyl-N,N-dimethylethanolamine 반응에서 유동성 변화와 상전이에 관한 연구)

  • Kim, Ki-Jun;Sung, Wan-Mo;Lee, Joo-Youb
    • Journal of the Korean Applied Science and Technology
    • /
    • v.32 no.1
    • /
    • pp.165-169
    • /
    • 2015
  • N-propyl-N,N-dimethylethanolamine was directly ultrasonicated in acidic water for 6 minute to give clear stock solutions. The catalytic hydrolysis of N-propyl-N,N-dimethylethanolamine was studied at $30{\sim}55^{\circ}C$ in the presence of uni-lamellar vesicle and mixture of uni- and multi-lamellar aggregates. The difference of rate between uni- and mixture was observed, where uni-lamellar reaction was more catalytic effect. The phase transition temperature of vesicle was $37{\sim}44^{\circ}C$. The particle size of multi-lamellar than that of uni-lamellar of biological membrane was measured more largely.

An optimal inventory management system for high-rise building -Focused on Re-bar Works- (초고층 건축공사의 특수성을 고려한 최적 자재 재고 관리 방안에 관한 연구 -철근공사를 중심으로-)

  • Kim, Geun-Hwan;Lee, Su-Hwan;Yun, Jung-Suk;Park, Kyung-Mo;Kim, Chang-Duk
    • KIEAE Journal
    • /
    • v.13 no.1
    • /
    • pp.151-157
    • /
    • 2013
  • Since high-rise building construction sites are usually located in crowded city areas, sufficient spaces for the inventories of key materials are rarely available. This spatial constraints have been one of the critical challenge that may cause productivity loss and increasing costs of the high-rise building construction projects. The proper material inventory management is certaing a key to the success of high-rise building construction projects as it handles difficulty of securing material stock yards, changes in demands, uncertain delivery time through integrating the construction schedules and actively responding to the key materials attributes. In this light, this research analyzes the latest inventory model, (Q,r) model, in accordance with the high rise building characteristics. This research suggests an optimal inventory management of re-bar considering various demands and lead times. The case study is also presented with regard to the re-bar inventory management.