• Title/Summary/Keyword: Entering point

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Determination of the Entering Point and the Number of AGVs required in the Flow Shop Type FMS (Flow Shop 형태를 갖는 FMS에서의 AGV투입시점과 필요댓수의 결정)

  • Yang, Dae-Yong;Chung, Byung-Hee;Lee, Jong-Min
    • Journal of Korean Institute of Industrial Engineers
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    • v.17 no.1
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    • pp.109-115
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    • 1991
  • In automated manufacturing systems, Automated Guided Vehicle(AGV) Systems are increasingly important in material handling and manufacturing operations. A considerably flexible AGV system needs to be operated with maximum effectiveness. This paper develops an algorithm for the determination of the entering point and the number of AGVs required in the Flow Shop Type FMS. We consider an AGV used as a carrier and mobile workstation. For the limited number of AGV, the entering point of an AGV on a simple loop is determined in order to maximize the utilization of AGVs. For the unlimited number of AGVs, the number of AGVs required in the FMS is determined on the basis of the entering point of AGVs. The result by the algorithm may be used as a criterion on the control of material flow and the assignment of AGVs in the FMS. A numerical example is given to illustrate the algorithm.

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The Fundamental Study of Strength and Drying Shrinkage on Alkali-activated Slag Cement Mortar with Different Entering Point of Fine Aggregate (잔골재의 투입시점에 따른 알칼리 활성화 슬래그 모르타르의 강도와 건조수축에 대한 기초적 연구)

  • Kim, Tae-Wan;Eom, Jang-Sub;Seo, Ki-Young;Park, Hyun-Jae
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.18 no.2
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    • pp.117-125
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    • 2014
  • This paper examines the fundamental properties of alkali-activated slag cement (AASC) activated by sodium hydroxide (NaOH). The water to binder (W/B) ratio was 0.4 and 0.5. And concentration of activator were 2M and 4M. Five mix design of each W/B ratios was considered. The N0 mixture was KS L 5109 method and N1~N4 were varied in different mixing time, mix step and entering points of fine aggregate. Test results clearly showed that the flow value, strength and drying shrinkage development of AASC were significantly dependent on the entering point of fine aggregate. The flow value tended to decreases with delaying entering point of fine aggregate. The compressive strength and flexural strength increases with delaying entering point. Moreover, the XRD analysis confirmed that there were sustain these results. The drying shrinkage increases with delaying entering point of fine aggregate. Futhermore, a modified mixing method incorporating all hereby experimentally derived parameters, is proposed to improvement the physical properties of AASC.

An Experimental Study on the Cooling Operation Characteristics for Different Entering Water Temperatures In Geothermal Heat Pump System (지열히트펌프 시스템의 EWT의 변화에 따른 냉방운전 특성에 관한 실험적 연구)

  • Ahn, Byung-Chun;Kim, Jae-Wan
    • Journal of the Korean Society for Geothermal and Hydrothermal Energy
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    • v.6 no.1
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    • pp.1-7
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    • 2010
  • In this paper, an experimental study on the cooling operation characteristics for different entering water temperatures in geothermal heat pump system are carried out by using Lab VIEW system program Set-point temperature controls for cooling water and supply air temperatures is applied to analyze the energy consumption and control performances. As a result, the system responses show that different entering water temperatures(EWT) effect greatly on the energy consumption and system COP.

Flow Control Method for Resolving Non-Point Pollutants in Road Surface in Initial Rainfall (초기 강우 시 도로면 비점오염원 해소를 위한 유량제어 방법)

  • Han, Sang-Bae;Kim, Nam-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2021.05a
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    • pp.220-223
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    • 2021
  • This paper concerns a flow control method that can reduce rainwater containing non-point contamination accumulated on road surfaces during initial rainfall. In early rainfall, non-point pollutants are blocked from entering rivers and oceans and flow to sewage treatment plants. Afterwards, rainwater, which has been removed from the non-point pollution source through jet lag, is safely flowing into the river.

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Nanotechnology and Occupational Health Addressing Potential Health Risks

  • Maynard Andrew
    • Proceedings of the Korea Environmental Mutagen Society Conference
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    • 2005.05a
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    • pp.21-26
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    • 2005
  • [ $\cdot$ ] Occupational safety and health is a key component of responsible nanotechnology $\cdot$ Nanotechnology challenges conventional approaches to addressing occupational safety and health risk $\cdot$ Nanomaterials and devices of concern include those capable of entering the body and causing harm as a result of their nanostructure $\cdot$ Proactive risk assessment and management requires extensive strategic research $\cdot$ Current knowledge provides a staring point for addressing risk

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A Study on the Accuracy Improvement of Control Point Surveying of Photograph Using Digital Camera (디지털 카메라를 이용한 사진기준점측량의 정확도 향상에 관한 연구)

  • Kim, Kye-Dong;Park, Joung-Hyun;Lee, Young-Wook
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.27 no.2
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    • pp.203-211
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    • 2009
  • With supply of the domestic digital camera, the relative importance of the digital camera is coming to be high gradually on aerial photogrammetry, the image of digital camera is more applied in image map or digital topographic map production. But, there are cases that do not have position information or attitude information of each photograph in digital camera results. Therefore, we wish to present additional method to get more accurate photograph control point result. In this study, One is called A method, which is the case of entering positioning information of principal point from topographic map as default values that are need to extract tie point automatically using by 56 pieces of photography that are photographed by DMC to the extent to 5 courses and 35 GCP points. The other is called B-method, which is the case of entering exterior orientation parameters that are processed by block adjustment for A-method using by 4 control points in method-1 as default values. We have analyzed about results per control points arrangement for two cases using MATCH-AT that is photograph control point measurement S/W of Germany INPHO company. As a result of analysis, accuracy of B-method was better than that of A-method, and we could get more accurate results if block adjustments are executed including self calibration. Also, it is more effective in expense side that using self calibration for photograph survey in B-method because can reduce GCP numbers.

An Efficient Multicast Scheme for Hierarchical Mobile IPv6 (계층적 Mobile IPv6를 위한 효율적 멀티캐스트 방안)

  • Kim, Byung-Soon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.7A
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    • pp.597-602
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    • 2005
  • This paper proposes an efficient multicast scheme for the hierarchical mobile IPv6(HMIPv6). If a mobility anchor point(MAP) in a new domain does not support multicasting, an entering group member cannot join the multicast group through the new MAP The group member thus keeps receiving multicast packets from its home agent(HA) using Mobile IPv6 (MIPv6). This increases the propagation delay of binding update (BU) messages. However, our scheme enables an entering group member to keep receiving packets from the old multicast MAP. It can also reduce tunneling costs, total delivery costs and handover latency. We simulated the performance of our scheme by comparing it with the seamless multicast handover in a hierarchical mobile Pv6 (M-HMIPv6) using the delivery cost and handover latency factors.

The Prediction of Wave Groups within a Harbor to Assist Ship Operation at the Entrance

  • Cho Ik-Soon
    • Journal of Navigation and Port Research
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    • v.30 no.2
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    • pp.125-130
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    • 2006
  • Waves, which are the main source of ship motions in a seaway, considerably affect the performance of a ship. The study of waves and their impact on ship motions within harbors is an important aspect of the design and operation of harbors. The prediction of incoming groups of waves is particularly important for evaluating ship motion within a harbor. Such a prediction makes it possible to evaluate ship safety more accurately. The wave transformation model reported here is applied to actual ports based on Boussinesq wave equations both non-linear and dispersive wave processes be considered in order to capture physical effects such as wave shoaling, refractions, reflection and diffraction in variable depth environments. The prediction of incoming groups of waves is particularly important for evaluating ship motion within a harbor, Such a prediction makes it possible to evaluate ship safety more accurately and provide safe wave informations for navigation. Furthermore, a wave information support system is proposed for entering ships as one technique for improving the safety of ship operations. This system predicts the run of waves and reduces the danger by identifying the most dangerous point near the harbor entrance at the small wave groups.

Nomura Real Estate Initiatives & Promotion Structure System

  • Yutaka Hayasaka;Kazuya Matsumoto
    • International conference on construction engineering and project management
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    • 2024.07a
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    • pp.1305-1305
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    • 2024
  • Nomura Real Estate is not just an investor but is actively involved in project promotion. Before construction begins, we review all drawings and point out areas that may lead to defects, check process charts and propose more rational processes, inform how to manage cost increases and decreases due to changes during construction, and provide advice from the perspective of quality, process and cost management by entering the project to enhance property value. We also provide advice from the perspectives of quality, process, and cost management by entering projects to improve property value. Depending on the project, we also work with third parties such as general contractors, manufacturers, and academic experts to propose products and new technologies that are not available locally. We have built a promotion system in which teams are formed centered around staff from the head office, with the addition of local staff from each country and third parties for each project. In recent years, we have been working on activities (knowledge exchange, manuals, internal forums, etc.) to horizontally expand our knowledge by providing opportunities for local staff to interact with each other, rather than keeping the knowledge gained through overseas business at the head office or in each country. This cycle of knowledge accumulation, deployment, and application enhances the quality of our projects, which in turn leads to the trust of our partners in each country.

Analysis of Flow Phenomena in a Centrifugal Compressor Impeller Operating near Stall (스톨 근처에서 원심압축기 임펠러의 내부 유동현상에 관한 연구)

  • Eum, Hark-Jin;Kang, Shin-Hyoung
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.28 no.3
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    • pp.330-337
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    • 2004
  • Analysis of flow phenomena in a centrifugal compressor impeller has been carried out with numerical simulation to understand the physics of flow near stall. Near stall point, tip leakage flow spills ahead of the leading edge of adjacent blade and other leakage flow passes over the clearance of the adjacent blade instead of rolling up into vortex within the passage. The tip leakage flow at the mid chord of impeller blade impinges against the pressure surface of the adjacent blade and then rolls up into vortex within the passage, which blocks the flow passage and generates viscous loss. The spillage of leakage flow ahead of the adjacent blade generates the recirculation of flow entering the impeller, which causes the power transferred into the flow by the impeller to decrease and blocks the flow passage. Near diffuser hub wall, flow recirculation occurs. As operating point goes to stall point, the core of recirculation approaches the impeller exit The length rises to peak point and then drops with mass flow reduction, while the height steadily rises.