• Title/Summary/Keyword: inner system

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An Evaluation of Constituent Factors for Port Logistics (항만물류 구성요소의 평가에 관한 연구)

  • Yeo, Gi-Tae;Jung, Hyun-Jae;Kim, Jae-Young
    • Journal of Korea Port Economic Association
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    • v.27 no.3
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    • pp.273-288
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    • 2011
  • Recently, the rankings of Korean container ports in terms of container handling cargo volume were plunged down due to the emerging Chinese ports. The efficient container ports strategies which increase container port competitiveness were requested. In this respect, it is urgently required to draw out constituent factors for Port Logistics, weigh these factors, and finally focus on improving the suggested factors. The aim of this paper is to evaluate weight and priority values for 'inner consisted factors' and 'outer requested factors' of port logistics by using the AHP(Analytic Hierarchy Process) method. As for the analysis regarding the inner consisted factors, the results were shown as follows: a storage and handling system (0.288) as the first rank; an information system of port logistics (0.210) as the second rank; an inland intermodal system (0.189) as the third rank; a ship's entering and departuring system (0.184) as the fourth rank, and a ship's berthing system (0.129) as the fifth rank. In terms of analysis regarding outer requested factors, the results came out as follows: a logistics cost (0.360) as the first rank; a port service (0.128) as the second rank; a connectivity (0.118) as the third rank; a hinterland condition (0.116) as the fourth rank; an convenience (0.106) as the fifth rank; a regional center (0.095) as the sixth rank, and an availability (0.077) as the seventh rank. For analyzing the priorities changes in constituent factors, the comparison of results between the year 2007 and the year 2011 was done. As the results, among inner consisted factors, 'information system of port logistics' was ranked first in the year 2007 while 'a storage and handling system' became the most important factor in the year 2011. Among the inner consisted factors, however, the logistics cost was the important factor in 2007 and 2011, respectively.

A Pyramidal Mirror System Calibration Method for Robotic Assembly

  • Kim, J.Y.;Kang, D.J.;Kim, M.S.;Ha, J.E.;Lho, T.J.;Yoon, J.S.
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.2435-2439
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    • 2005
  • In case of visual sensing systems with multiple mirrors, systematic errors need to be reduced by the system calibration and the mirror position adjustment in order to enhance system measurement accuracy. In this paper, a self calibration method is presented for a visual sensing system designed to measure the three-dimensional information in deformable peg-in-hole tasks. It is composed of a CCD camera and a series of mirrors including two pyramidal mirrors. By using an image of the inner pyramidal mirror taken by the system, the error parameters of the inner pyramidal mirror could be calibrated or adjusted. Also the influence of the plane mirrors is investigated.

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Displacement-Type Web Position Control of Cold Mills Using QFT (QFT를 이용한 냉간 압연시스템의 변위유도형 웹 위치제어)

  • Jeong, Jae-Hyo;Kim, Jong-Sik;Park, Jeon-Soo
    • Journal of the Korean Society for Precision Engineering
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    • v.18 no.9
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    • pp.147-155
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    • 2001
  • A new displacement type web position control system for cold mills using QFT is presented. The control system features an inner-outer cascaded system in which the inner loop provides the position tracking control of the hydraulic system and the outer loop provides the position regulation control of the web. By the sensitivity analysis and computer simulation, it is verified that the proposed control system has better robust stability and performance than the conventional control system.

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Rotordynamic Characteristics of an APU Gas Turbine Rotor-Bearing System Having a Tie Shaft

  • Lee, An-Sung;Lee, Young-Seob
    • Journal of Mechanical Science and Technology
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    • v.15 no.2
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    • pp.152-159
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    • 2001
  • In this paper it is intended to set-up a sound model of the 60,000rpm 100kW prototype APU gas turbine rotor-bearing system, and particularly to investigate the influences of the tie shaft on the rotordynamic characteristics of the entire APU gas turbine rotor-bearing system, employing the dual shaft model. Firstly, a mock-up APU rotor has been constructed to test and verify the model. Analytical natural frequency results have agreed with the corresponding modal test ones to within 5% difference. Then, the rotordynamic characteristics of the prototype APU rotorbearing system have been investigated. Natural vibration and unbalance response analyses results have shown that the inner tie shaft resonance can cause high enough vibration of the outer main rotor shaft. This could be a concern as the rotor journals operate on very thin air film at high speed. It is concluded as a conservative design practice that the inner tie shaft should be explicitly modeled in the rotordynamic analysis of the APU rotor-bearing system.

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Steering-Type Web Position Control of Cold Mills Using QFT (QFT를 이용한 냉간 압연시스템의 조타유도형 웹 위치제어)

  • Lee, Gyu-Jun;Jeong, Jae-Hyo;Kim, Jong-Sik;Choe, Jin-Tae
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.26 no.1
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    • pp.31-38
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    • 2002
  • A new steering-type web position control system for cold mills using QFT is presented. The control system features an inner-outer cascaded system in which the inner loop provides the position tracking control of hydraulic system and the outer loop provides the position regulation control of the web. By the sensitivity analysis and computer simulation, it is verified that the proposed control system has better robust stability and performance than the conventional PH) control system.

Diet Folate, DNA Methylation and Polymorphisms in Methylenetetrahydrofolate Reductase in Association with the Susceptibility to Gastric Cancer

  • Gao, Shang;Ding, Li-Hong;Wang, Jian-Wei;Li, Cun-Bao;Wang, Zhao-Yang
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.1
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    • pp.299-302
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    • 2013
  • Methylenetetrahydrofolate reductase (MTHFR) has been reported to be associated with DNA methylation, an epigenetic feature frequently found in gastric cancer. We conducted a case-control study to explore the association of MTHFR C677T polymorphisms with gastric cancer risk and its relation with the DNA methylation of COX-2, MGMT, and hMLH1 genes. Genotyping of P16, MGMT and HMLH1 was determined by methylation-specific PCR after sodium bisulfate modification of DNA, and genotyping of MTHFR C677T was conducted by TaqMan assays using the ABI Prism 7911HT Sequence Detection System. Folate intake was calculated with the aid of a questionnaire. Compared with the MTHFR 677CC genotype, the TT genotype was significantly associated with 2.08 fold risk of gastric cancer when adjusting for potential risk factors. Individuals who had an intake of folate above $310{\mu}g$/day showed protective effects against gastric cancer risk. The effect of MTHFR C677T polymorphisms on the risk of gastric cancer was modified by folate intake and methylation status of MGMT (P for interaction <0.05).

A Study on the Residents Characteristic and the Inner Space Use of Small-Sized Rental Multi-family Housing (소형 임대주택 가구특성 및 실내공간 이용실태 조사 연구)

  • Baik, Hye-Sun;Yim, Mi-Sook
    • Journal of the Korean housing association
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    • v.15 no.6
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    • pp.1-13
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    • 2004
  • As the provision of National Rental Housing has led the consciousness on rental housing changed, it becomes more necessary to improve the quality of rental housing. The purpose of this study is to analyze the inner space use of a unit and residents' consciousness on the results of surveying the residents in order to construct rental housing which provides comfort residental environment for the residents. Data was collected through questionnaire surveys(459 residents) from 5 estates including 3 estates of National Rental Housing and 2 estates of Public Rental Housing, which is $36m^{2}\;and\;45m^{2}$ of net area of a unit, for the actual use conditions and their requirements on the inner space of a unit. The results are as follows ; 1) The rental housing differentiated according to the needs from the residents' characteristics should be developed. 2) The main demand household for rental housing is established to that of 4 families including a 40s year-old couple and that of 3 or 4 families including a 30s year-old couple, and a double income family. But the type of household becomes more diverse than before. 3) It is necessary to plan the living room for the Multi-functional inner space emphasizing commom space 4) The various and efficient storage space and system for the residents' demands.

Construction History of the Old House "IMCHEONGGAK" in Andong and Estimation of its Original Structure -Focused on the 'Inner chamber' and the 'Sarang section'- (안동 "임청각(臨淸閣)"의 건축 이력과 원형 가구(架構) 추정 -사랑채와 안채를 중심으로-)

  • Lee, Jong-Seo
    • Journal of architectural history
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    • v.25 no.2
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    • pp.31-44
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    • 2016
  • Imcheong-gak[臨淸閣] was a familial residence constructed in the early half of the Joseon dynasty period. It was partially destroyed by a fire during the 1590s war[壬辰倭亂] with the Japanese, and another fire that was caused between 1631 and 1634. The inner chamber[An-chae] and the Sarang section[Sarang-chae] today is the result of a partial reconstruction that took place back in 1626 and again around 1634. The residence also went through some changes because the new Ondol[溫突] heating system had to be applied to the structure. Based upon sections that remain in their original forms, we can presume that the Imcheong-gak residence originally had an inner chamber which was composed of the following elements: A main structure which was built upon a foundation featuring a Matbae[맞배] roof, two "Ik'rang[翼廊, flank]" sections on the East and West sides of the inner chamber, and a "Haeng'rang[行廊, passage]" structure on the opposite side of the main structure. Unlike the main structure, other portions of the inner chamber were all built directly upon the ground, and showed multiple stories, with Matbae roofs of their own. We can also assume that the Sarang section in the south would have been a pre-Ondol[溫突] bedroom, with a Board platform[板房] and a Gomi-ceiling[Gomi-banza] fashion.

Filler effect of inner-structure bonded sheet metal in shearing process (내부구조재를 가진 중공형 접합판재의 전단가공특성에서 틈새효과에 관한 연구)

  • Kim, Ji-yong;Jung, Wan-jin;Kima, Jong-ho
    • Design & Manufacturing
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    • v.2 no.1
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    • pp.15-19
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    • 2008
  • While recent industrial structure is various, it is small quantity batch production structure, and products requiring of various functions are increasing. In order to improve the quality of the sheared surface in cutting of inner structure bonded sheet metal the cut-off operation is mainly investigated, which is the typical shearing process in sheet metal forming technology. The sandwich sheet metals considered have inner structure which is constructed in the form of crimped expanded metal and woven metal. The inner structure is bonded between solid sheet by resistance welding or adhesive bonding. The shearing process is visualized by the computer vision system installed in front of the cut-off die and the sheared surface is measured and quantitatively compared with the help of the optical microscope after cut-off operation. From test results we found that the influence of sheared position can be observed and explained clearly and this result can be utilized to get the better sheared surface.

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Rotordynamic Influences of a Tie Shaft in a APU Gas Turbine Rotor-Bearng System (보조동력 개스터빈 로터-베어링 시스템에서 체결축의 로터다이나믹 영향)

  • Lee, An-Sung;Lee, Young-Seob
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.06a
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    • pp.1051-1057
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    • 2000
  • A projected 100 kW APU gas turbine rotor-bearing system has a main outer shaft, which is composed of some numbers of segmented sections for manufacturing and assembly conveniences. For a secure assembly of the segmented sections a tie shaft or inner shaft is installed inside of the outer shaft and a tensional axial preload of 50,000 N is provided to it. In this paper it is intended to set-up a sound modeling method of the APU rotor system, and particularly, the influences of the tie shaft on the rotordynamic characteristics of the entire APU gas turbine rotor-bearing system are investigated. Analysis results show that as a conservative design practice the inner tie shaft should be actively modeled in the rotordynamic analysis of the APU rotor-bearing system, and its effects on the dynamic behaviors of the outer shaft should be thoroughly design-reviewed.

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