• Title/Summary/Keyword: leveling

Search Result 572, Processing Time 0.03 seconds

Resource Leveling using Genetic Algorithm (유전알고리즘을 활용한 자원평준화 방법론)

  • Gwak, Han-Seong;Bea, Sang-Hee;Lee, Dong-Eun
    • Journal of the Architectural Institute of Korea Structure & Construction
    • /
    • v.34 no.2
    • /
    • pp.67-74
    • /
    • 2018
  • Resource leveling minimizes resource fluctuations by deferring the earliest start times (ESTs) of non-critical activities within their corresponding total float. The intentional float-consumption for resource leveling purpose reduces the schedule delay contingency. This paper presents a method called Genetic Algorithm based Resource Leveling (GARL) that minimizes resource fluctuations and float-consumption impact over project duration. It identifies activities that are less sensitive to float-consumption and performs resource leveling using those activities. The study is of value to project scheduler because GARL identifies the set of activities to be deferred and the number of shift day(s) of each and every activities in the set within its total float expeditiously. It contributes to establish a baseline schedule which implements an optimal resource leveling plan. A case study is presented to verify the validity and usability of the method. It was confirmed that GARL satisfies the project duration constraint by considering resource fluctuations and float-consumption over project duration.

A wear-leveling improving method by periodic exchanging of cold block areas and hot block areas (Cold 블록 영역과 hot 블록 영역의 주기적 교환을 통한 wear-leveling 향상 기법)

  • Jang, Si-Woong
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2008.05a
    • /
    • pp.175-178
    • /
    • 2008
  • While read operation on flash memory is fast and doesn't have any constraints, flash memory can not be overwritten on updating data, new data are updated in new area. If data are frequently updated, garbage collection, which is achieved by erasing blocks, should be performed to reclaim new area. Hence, because the number of erase operations is limited due to characteristics of flash memory, every block should be evenly written and erased. However, if data with access locality are processed by cost benefit algorithm with separation of hot block and cold block, though the performance of processing is high, wear-leveling is not even. In this paper, we propose CB-MG (Cost Benefit between Multi Group) algorithm in which hot data are allocated in one group and cold data in another group, and in which role of hot group and cold group is exchanged every period. Experimental results show that performance and wear-leveling of CB-MG provide better results than those of CB-S.

  • PDF

A Study on the Refraction Errors of Light in the Precise Leveling (정밀 수준측량에 있어서 빛의 굴절오차에 관한 연구)

  • 이계학
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.15 no.1
    • /
    • pp.9-20
    • /
    • 1997
  • The precise leveling is one of the important means of investigating fluctuation of earth's crust and foreknowing earthquake. This paper aims to study refraction errors developed in the inclined leveling route. Based on Kukkamaki's theory and data of weather, the author devised an experiment to test how Kukkimaki's corrections improved the discrepancy between fore and back sight leveling in actual slope. Additionally, through the repeated observation between fore and back sight leveling at one fixed station in the slope(2/100-4/100) and the experimental tests of continuous inclined leveling route, the author studied the effects and charcteristics of refraction. Especially, in inclined leveling(2/100-4/100), the distance of line of sight is ideally to be 25-30 m to minimize refraction errors. From the results of experimental tests of continuous inclined leveling route, the values of calculation by Kukkimaki's corrections were found to be nearly in accord with the values of observation.

  • PDF

A Development of Ship Block Leveling System based on the Axiomatic Design (공리적 설계 기반 선체 블록 레벨링 시스템 개발)

  • Noh, Jackyou;Lim, Nam-Won;Oh, Jung-Keun
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.21 no.2
    • /
    • pp.207-214
    • /
    • 2015
  • In this paper the independence axiom, one of two principal axioms of axiomatic design theory, is applied to the leveling system development as an design criteria. After functional requirements and corresponding design parameters constitute an initial design matrix for the leveling system, sequence, which is compatible with the independence axiom, of the design parameters of the design matrix is determined and independent components of block leveling system are revealed. As a result of axiomatic design, system configuration related to the design sequence is developed. In order to verify and validate the developed block leveling system, test with real hull block leveling work in site by using total station which is used to acquire three dimensional coordinate of target point is performed. Comparison with measured data and output data from the block leveling system shows the system accuracy is under 1 mm so that the developed system is verified and validated to be used in site.

Test tool for flow and self-leveling characters of coating materials of siloxane polymer used to semiconductor and electronic parts (반도체와 전자 부품에 사용되는 실록산 고분자 코팅물질의 흐름성 및 자기 퍼짐성 측정 시험장치 연구)

  • Kim, Cheol-Hyun;Cho, Hyeon-Mo;Lee, Myong-Euy
    • Analytical Science and Technology
    • /
    • v.25 no.2
    • /
    • pp.127-132
    • /
    • 2012
  • A test tool for self-leveling and flowing characters of coating materials used to semiconductors and electronic parts, especially for protection of LCD and PDP connectors, was designed, and the test tool was evaluated using polymeric siloxane coating materials which have various viscosities. The test results showed that the designed test tool was effective to measure self-leveling and flowing properties of coating materials. Therefore, considering that the viscosity is not directly correlated with self-leveling and flowing properties, we believe that this test tool will be a very useful tool for measurement instead of classical method using viscosities of coating materials. Particularly, the measurement of self-leveling and flowing properties using the test tool would be expected to be used in the area of selecting suitable protective coating materials for LCD (Liquid Crystal Display), PDP (Plasma Display Panel) and semiconductor connection parts.

A method for improving wear-leveling of flash file systems in workload of access locality (접근 지역성을 가지는 작업부하에서 플래시 파일시스템의 wear-leveling 향상 기법)

  • Jang, Si-Woong
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.12 no.1
    • /
    • pp.108-114
    • /
    • 2008
  • Since flash memory cannot be overwritten, new data are updated in new area. If data are frequently updated, garbage collection which is achieved by erasing blocks, should be performed to reclaim new area. Hence, because the count of erase operations is limited due to characteristics of flash memory, every block should be evenly written and erased. However, if data with access locality are processed by cost benefit algorithm with separation of hot block ad cold block though the performance of processing is hight wear-leveling is not even. In this paper, we propose CB-MB (Cost Benefit between Multi Bank) algorithm in which hot data are allocated in one bank and cold data in another bank, and in which role of hot bank and cold bank is exchanged every period. CB-MB shows that its performance is 30% better than cost benefit algorithm with separation of cold block and hot block its wear-leveling is about a third of that in standard deviation.

A New Method for Leveling Airborne Gamma-ray Spectrometric Data (항공 방사능 탐사 자료 맞추기의 새로운 방법)

  • Park, Yeong-Sue;Rim, Hyoungrea;Lim, Mutaek;Shin, Young Hong
    • Geophysics and Geophysical Exploration
    • /
    • v.19 no.4
    • /
    • pp.179-186
    • /
    • 2016
  • Data leveling utilizing baseline survey makes existing old data be smoothly compiled, and also keep characteristics of data, such as small high frequency anomaly information. The previously proposed leveling method may easily loose or damage the original characteristics of the data. This paper suggests a new leveling method. New method determines the leveling coefficients using regional field of the original data, which is composed by data on the grids point coincided with baseline survey grid, while existing method uses all grid data without any considerations. Results of new leveling method on test area shows that new method make two data sets compiled more smoothly and trends of data distribution expressed more clearly. And then, it also preserves high frequency information well.

Parameter Study of Roller Leveling Process of Steel Cord Using Finite Element Analysis (유한요소해석을 이용한 스틸코드 롤러교정공정의 영향인자 분석)

  • Bae, G.H.;Lee, J.S.;Huh, H.;Lee, J.W.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
    • /
    • 2008.10a
    • /
    • pp.245-248
    • /
    • 2008
  • This paper deals with the parameter study of roller leveling process of steel cord using finite element analysis. A simplified model of roller leveling process is constructed for the efficient numerical simulation considering the computing time. Using the constructed simulation scheme, the parameter study of main process parameters, such as back-tension and intermesh, is carried out in order to evaluate elastic recovery angle and roller force quantitatively. The effect of the initial shape of steel cord is also evaluated during the parameter study. And the mechanism of roller leveling process is verified by investigating the residual stress distribution.

  • PDF

Evaluation on Crack in Self-leveling Material and Investigation about Influence of Specimen Size - Evaluation Method about Surface Layer Quality of Concrete Floor Groundwork Corresponding to Defect in Self-leveling Material (Part I) - (콘크리트 바닥 시험체의 크기가 SL재의 균열에 미치는 영향 - SL재의 하자 발생에 영향을 미치는 콘크리트 표층부의 품질 평가방법(I) -)

  • Kim, Doo-Ho;Choi, Soo-Kyung
    • Journal of the Korea Institute of Building Construction
    • /
    • v.7 no.2 s.24
    • /
    • pp.99-106
    • /
    • 2007
  • The purpose of this study presents in Relations between cracks in self-leveling material and quality of floor groundwork surface are experimentally examined. As the first stage, the experiment to observe cracks in self-leveling material constructed on floor groundwork made from various kinds of concrete was carried. As a result, following basic findings were obtained. First, observation of cracks should be continued until an increase in width of cracks stop, without constructing any finishing material. Second, degree of cracks may be indicated quantitatively by the product of length and width. Finally, Cracks and separation is not be influenced by specimen size. Based on these findings, the method of predicting cracks by evaluating surface layer quality of floor groundwork will be established.

AUTOMATIC LEVELING CONTROL SYSTEM FOR COMBINE

  • Lee, S. S.;K. S. Oh;H. Hwang;Park, D. Y.
    • Proceedings of the Korean Society for Agricultural Machinery Conference
    • /
    • 2000.11c
    • /
    • pp.684-689
    • /
    • 2000
  • In harvesting rice and barley using combine, the inclination of the body caused by the irregular surface condition of the field and the soil sinking from the unbalanced weight during the grain collection used to make harvesting operation difficult and even impossible. To overcome such a problem, automatic leveling control system for a combine has been developed and tested. The system was composed of the sensor for measuring left and right inclination of the combine chassis and the hydraulic control system. The adaptability of the control system was investigated by analyzing system response in time domain. And the limit angle of the leveling control was set up to be +/- 7$^{\circ}$. The proposed control and hydraulic power system was implemented to the prototype combine. The prototype combine was designed and built as a separable structure with chassis and track. This paper shows results of the leveling performance tested in the laboratory and the grain field.

  • PDF