• Title/Summary/Keyword: set-up

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A Dynamic Set-up Technique for High Accuracy set-up of Continuous Hot Strip Finishing Mill (열간 마무리압연 설정의 정도향상을 위한 동적 설정법)

  • 문영훈;이준정
    • Transactions of Materials Processing
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    • v.5 no.3
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    • pp.232-238
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    • 1996
  • A dynamic mill set-up technique was developed to achieva a more precise roll gap set-up of the finishing mill stands for steel strip rolling. In the conventional mill set-up model the set-up values such as roll gap and roll speed are determined before the sheet bar reached the entry side of the finishing mill train and maintained constant until the strip top end passes through the last stand. In the way however a dynamic set-up logic that gives a way to adjust the roll gap value of the final mill stand for the strip ingoing from the ahead of the front stand was developed and attached to the existing set-up model. The roll gap modification is based on the analysis of the observation in the third stand of the finishing mill train. The dynamic set-up model was proved very effective for the more precise mill set-up and for operational stability in the hot strip finishing mill train.

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The Effects of Set-up Cost Reduction in the Dynamic Lot Size Model and the EOQ model (동적로트크기결정모형과 EOQ모형에 있어서 가동준비비용의 감소효과)

  • ;Lee, Sang Bum
    • Journal of the Korean Operations Research and Management Science Society
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    • v.17 no.3
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    • pp.13-26
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    • 1992
  • Set-up reduction is an important aspect of the Japanese Just-In-Time (JIT) and Zero Inventory (ZI) concepts. In this paper, we first analyze the effects of set-up cost reduction on tatal inventory, average lot size and forecast horizon in the dynamic lot size model. We also examine the various effects of set-up cost reduction in the EOQ model and explain why many Japanese firms try to cut set-up cost and/or set-up time greatly.

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DYNAMIC SET-UP CONTROL OF TANDEM COLD MILL (연속압연기에서 OFF GAUGE 저감을 위한 DYNAMIC SET-UP 제어기술)

  • 노호섭;최병조;조뇌하;이재훈;김익준;진철제;박기영
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 1999.08a
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    • pp.126-131
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    • 1999
  • In order to reduce the length of off-gauge at FGC(Flying gauge change) point, We adopted dynamic set up in No. 4 cold rolling mill. The conventional set-up of FGC(Flying gauge change) was calculated on the basis of preset values in the process control computer, so the difference between actual strip thickness and preset thickness cause long off-gauge. The dynamic SET-UP control was calculated on the basis of actual strip thickness of FGC(Flying gauge change) point from X-ray gauge of mill entry and No.i stand. We applied dynamic SET-UP control in September last year. Compare to the previous result, the length of off-gauge is reduced by about 36%.

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The Characteristics of the Set-up Effect of Driven Piles (타입 말뚝의 지지력 증가효과 특성)

  • 조천환
    • Journal of the Korean Geotechnical Society
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    • v.19 no.4
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    • pp.235-246
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    • 2003
  • Since the study of Lee et al.(1994) there have been some case studies on the set-up effect of driven piles in Korea country. However, comprehensive examination on the analyses of the set-up effect with various testing data has not been carried out. In particular, the analysis of the influence of soil type and pile shape on the set-up effect has not been reported. It is necessary to analyse the test results of production piles in order to apply the set-up effect of driven piles for the field engineering. In this study some test piling and analyses were performed to give basic information to the piling design as well as the research on the set-up effect in sandy soils. The analyses on the set-up effect were performed with the monitoring data obtained from the high-strain dynamic loading tests. It was shown that the set-up effect of driven piles was not only affected by soil type but also by soil formation history It turned out that the set-up effect in sandy soils was considerable one that should not be ignored in the field, and that the bearing capacity increase of pile is mainly caused by the increase of shaft resistance. It was shown that the set-up effect of closed pile was larger than that of opened pile in clayey soils, while the set-up effect of opened pile was larger than that of closed pile in sandy soils.

Effect of Difference in Warm-Up Intensity During 75%1RM Bench Press Exercise on Number of Repetitions, Total Work, and RPP

  • Jeong, Hwan Jong;Kim, Ki Hong
    • International Journal of Internet, Broadcasting and Communication
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    • v.13 no.3
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    • pp.130-136
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    • 2021
  • The purpose of this study was to investigate the effect of the intensity of warm-up exercise on the physiological response and exercise performance during resistance exercise. For this purpose, 8 male college students with at least 1 year of experience in resistance movement were selected. The warm-up condition was set to NON condition (preparatory exercise not performed), 3 set condition, 6 set condition, and 9 set condition, and the intensity was different for each set. After warm-up, 75% 1RM of main exercise was performed, and blood pressure and heart rate were measured immediately after exercise to measure RPP. The number of repetitions and total work for each condition were measured as the number of repetitions and momentum during the main exercise. The measured data were analyzed by repeated measures two-way ANOVA. As a result, although there was no difference in Rate Pressure Product according to the warm-up conditions, the number of repetitions and total amount of exercise showed the highest in the 3-set condition. Therefore, it is thought that the number and intensity of warm-up exercises should be set appropriately during resistance exercise, and warm-up of 3 sets or more during resistance exercise is thought to decrease exercise performance.

A Study on the roll gap set-up at top-end in plate rolling using finite element analysis (유한요소해석을 이용한 후판 압연공정의 선단부 롤갭 설정연구)

  • Yim, H.S.;Jang, J.H.;Choi, M.K.;Seo, J.H.;Moon, Y.H.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2009.05a
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    • pp.252-255
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    • 2009
  • The roll gap set-up in the finishing mill is one of the most important technologies in the hot plate rolling process. As the target thickness can be obtained by the correct set-up of the roll gap, improving the roll gap set-up technology is very critical for plate thickness accuracy. The main cause of thickness variation in hot plate mills is the non-uniform temperature distribution along the length of the slab. The objective of this study is to adjust the roll gap set-up for the thickness accuracy of plate in hot rolling process considering top-end temperature drop. Therefore this study has concentrated on determining the correct amounts of roll gap to compensate thickness variation due to top-end temperature drop. The off-line simulation of compensated roil gap significantly decreases top-end thickness variation.

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Furnace Set-up Prediction System Using Neural Network (신경망을 이용한 용해로 최적 SET-UP 예측시스템)

  • 한부학
    • Journal of Intelligence and Information Systems
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    • v.2 no.1
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    • pp.109-120
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    • 1996
  • TV 부라운관 유리를 생산하기 위한 용해 공정은 원료의 투입에서부터 유리물이 생성될 때 까지 고온의 화확적 작용을 거친다. 유리몰을 생성하기 위한 여러 가지 조건중에서 용해로 내부에서의 유리몰의 온도 변화 및 이에 따른 제반 공정변수의 조정 설정치(Set-up)는 불량률에 밀접한 영향을 미친다. 그러나 고온의 밀폐된 환경에서 반응이 진행되므로 공정의 운전 요원들은 그들의 경험을 바탕으로 용해로의 운전상태를 파악하고 운전해 나간다. 본 연구에서는 이러한 경험적 판단에 따른 위험성을 가능한 한 줄이고 용해로의 안정적인 운영을 통하여 불량률을 감소시키기 위하여 용해로 최적 Set-up 예측 시스템을 개발하였다. 이 시스템은 일정 기간 동안의 용해로서 운전 상태와 불량률간의 관계를 신경망 기법을 이용하여 학습한 후에, 이를 이용하여 불량률을 유지하기 위한 Set-up 값을 예측하여 준다.

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Consideration of Set-up Effect in Wave Equation Analysis of Pile Driving. (Set-up 효과를 반영한 타입말뚝의 파동이론해석)

  • 천병식;조천환
    • Journal of the Korean Geotechnical Society
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    • v.15 no.2
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    • pp.95-104
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    • 1999
  • The bearing capacity of piles driven in soils showing set-up tendency increases with time. Though WEAP is an excellent tool for evaluating the driveability of driven pile, it has some limitations to predict reliable bearing capacity of pile after driving. It is because the existing WEAP method cannot take into account time-dependent soil properties after driving. The set-up effect should be accounted for to obtain a reliable bearing capacity by the WEAP. Unfortunately, there are no sufficient methods to take the set-up effect into consideration in wave equation analysis. This paper suggests an alternative to consider time effect in wave equation analysis through statistical analysis of dynamic load test data both at the end of driving and in the beginning of restrike. It is shown that the suggested parameters(quake and damping) would be more reliable than the existing one for the wave equation analysis of driven piles.

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A Study on the Roll Gap Set-up to Compensate Thickness Variation at Top-end in Plate Rolling (후판 압연시 선단부 두께편차 보상을 위한 롤갭 설정에 관한 연구)

  • Yim, H.S.;Joo, B.D.;Lee, G.Y.;Seo, J.H.;Moon, Y.H.
    • Transactions of Materials Processing
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    • v.18 no.4
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    • pp.290-295
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    • 2009
  • The roll gap set-up in the finishing mill is one of the most important technologies in the hot plate rolling process. As the target thickness can be obtained by the correct set-up of the roll gap, improving the roll gap set-up technology is very critical for plate thickness accuracy. The main cause of thickness variation in hot plate mills is the non-uniform temperature distribution along the length of the slab. The objective of this study is to adjust the roll gap set-up for the thickness accuracy of plate in hot rolling process considering top-end temperature drop. Therefore this study has concentrated on determining the correct amounts of thickness variation according to top-end temperature drop and roll gap to compensate thickness variation. The control method of roll gap set-up which can improve the thickness accuracy was proposed. The off-line simulation of compensated roll gap significantly decreases top-end thickness variation.

The consideration about exact set-up with stereotactic radiosurgery for lung cancer. (폐암 환자의 전신 정위적 방사선 수술시 정확한 SET UP에 대한 고찰)

  • Seo, Dong-Rin;Hong, Dong-Gi;Kwon, Kyung-Tea;Park, Kwang-Ho;Kim, Jung-Man
    • The Journal of Korean Society for Radiation Therapy
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    • v.16 no.2
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    • pp.1-8
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    • 2004
  • Purpose : What confirm a patient's set-up precisely is an important factor in stereotactic radiosurgery Especially, the tumor is moved by respiration in case of lung cancer. So it is difficult to confirm a exact location by L-gram or EPID. I will verify a exact patient's set-up about this sort of problem by verification system(exactrac 3.0) Materials and Methods : The patient that had lung cancer operated on stereotactic radiosurgery is composed of 6 people. The 5 patients use an ABC tool and 1 patient doesn't use it. I got such a patient's L-gram and EPID image by Body frame(elekta, sweden), compared Ant. image with Lat. one, and then confirmed a set-up. I fused DRR image of CT and X-ray image of Verification system(exactrac 3.0) 3 dimensional, analyzed the coordinate value(vertical, longitudinal, lateral), and then confirmed a difference of existing method. Results : In case of L-gram and EPID, we judge an exact of the patient's set-up subjectively, and on we could treat the patient with radiation. As a result of using Verification system(exactrac 3.0), coordinate value(vertical, longitudinal, lateral) of patient's set-up was comprised within 5mm. We could estimate a difference of the coordinate value visually and objectively. Consequently, Verification system(exactrac 3.0) was useful in judging an exact patient's set-up. Conclusion : In case of Verification system(exactrac 3.0), we can confirm an exact patient's set-up at any time whenever, However, there are several kinds of the demerit. First, it is a complex process of confirmation than the existing process. Second, thickness of CT scan slice is within 3mm. The last, X-ray image has to have shown itself clearly. If we solve this problem. stereotactic radiosurgery will be useful in treating patients why we can confirm an exact patient's positioning easily.

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