• 제목/요약/키워드: Systematic error

검색결과 494건 처리시간 0.028초

Improving data reliability on oligonucleotide microarray

  • Yoon, Yeo-In;Lee, Young-Hak;Park, Jin-Hyun
    • 한국생물정보학회:학술대회논문집
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    • 한국생물정보시스템생물학회 2004년도 The 3rd Annual Conference for The Korean Society for Bioinformatics Association of Asian Societies for Bioinformatics 2004 Symposium
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    • pp.107-116
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    • 2004
  • The advent of microarray technologies gives an opportunity to moni tor the expression of ten thousands of genes, simultaneously. Such microarray data can be deteriorated by experimental errors and image artifacts, which generate non-negligible outliers that are estimated by 15% of typical microarray data. Thus, it is an important issue to detect and correct the se faulty probes prior to high-level data analysis such as classification or clustering. In this paper, we propose a systematic procedure for the detection of faulty probes and its proper correction in Genechip array based on multivariate statistical approaches. Principal component analysis (PCA), one of the most widely used multivariate statistical approaches, has been applied to construct a statistical correlation model with 20 pairs of probes for each gene. And, the faulty probes are identified by inspecting the squared prediction error (SPE) of each probe from the PCA model. Then, the outlying probes are reconstructed by the iterative optimization approach minimizing SPE. We used the public data presented from the gene chip project of human fibroblast cell. Through the application study, the proposed approach showed good performance for probe correction without removing faulty probes, which may be desirable in the viewpoint of the maximum use of data information.

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원통기어의 다단면 치형 측정평가 (The Evaluation of Cylindrical Gear Measurement on Teeth Roots and Bottom Profiles in Different Sections)

  • 문성민;강재화;키도히로미쯔;구로가와슈헤이;류성기
    • 한국기계가공학회지
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    • 제11권1호
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    • pp.46-49
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    • 2012
  • Gears are reliable and efficient power transmission elements. They have been widely used in all kinds of machinery. Nowadays, resource conservation energy conservation environmental improvements from the request of the compact, light weight, high efficiency, low cost Higher efficiency is required. Tooth root and bottom profiles of cylindrical gears affect bending fatigue life, but they are hard to measure with conventional gear measuring machine(GMM), because GMM is normally customized to measure only gear working flanks. The authors try to develop a new type of GMM by installing an extra 3D scanning probe and control software to measure tooth root and bottom profiles. First, in order to measure in various directions, a 3D scanning probe has been attached to the GMM developed. Next, calibration algorithm has been developed. Deviations of the calibration results are measured and it is found that systematic error must be caused by heat from driving motors. A new alternative GMM with driving motors generating less heat was designed and two GMMs are compared. Finally, 3 Dimension measurement of tooth root and bottom profiles of cylindrical gears is described.

그루브를 이용한 표면형상변형 동특성 변경법 : HDD 커버에 대한 적용 (Structural Dynamics Modification Using Surface Grooving Technique: Application to HDD Cover Model)

  • 박미유;박영진;박윤식
    • 한국소음진동공학회논문집
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    • 제15권3호
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    • pp.341-345
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    • 2005
  • Structural Dynamics Modification (SDM) is a very effective technique to improve structure's dynamic characteristics by adding or removing auxiliary structures, changing material properties and shape of structure. Among those of SDM technique, the method to change shape of structure has been mostly relied on engineer's experience and trial-and-error process which are very time consuming. In order to develop a systematic method to change structure shape, surface grooving technique is studied. In this work, the shape of base structure was modified to improve its dynamic characteristics such as natural frequencies via surface grooving technique. Grooving shape was formed by mergingthe neighboring small embossing elements after analyzing frequency increment sensitivities of all the neighboring emboss elements. For this process, Criterion Factor was introduced and the initial grooving was started from the element having highest strain energy and the grooving is expanded into neighboring element. The range of targeting grooving area to check its frequency variations restricted to their neighboring area to reduce the computation effort. This surface grooving technique was successfully applied to a hard disk drives (HDD) cover model to raise its natural frequency by giving some groove on its surface.

IDENTIFICATION OF HUMAN-INDUCED INITIATING EVENTS IN THE LOW POWER AND SHUTDOWN OPERATION USING THE COMMISSION ERROR SEARCH AND ASSESSMENT METHOD

  • KIM, YONGCHAN;KIM, JONGHYUN
    • Nuclear Engineering and Technology
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    • 제47권2호
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    • pp.187-195
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    • 2015
  • Human-induced initiating events, also called Category B actions in human reliability analysis, are operator actions that may lead directly to initiating events. Most conventional probabilistic safety analyses typically assume that the frequency of initiating events also includes the probability of human-induced initiating events. However, some regulatory documents require Category B actions to be specifically analyzed and quantified in probabilistic safety analysis. An explicit modeling of Category B actions could also potentially lead to important insights into human performance in terms of safety. However, there is no standard procedure to identify Category B actions. This paper describes a systematic procedure to identify Category B actions for low power and shutdown conditions. The procedure includes several steps to determine operator actions that may lead to initiating events in the low power and shutdown stages. These steps are the selection of initiating events, the selection of systems or components, the screening of unlikely operating actions, and the quantification of initiating events. The procedure also provides the detailed instruction for each step, such as operator's action, information required, screening rules, and the outputs. Finally, the applicability of the suggested approach is also investigated by application to a plant example.

화약류발파작업이 근골격계에 영향을 미치는 자세평가분석 (Anlaysis on the Influence of Work-related Musculoskeletal Disorders in Explosive Blasting Performance)

  • 이정훈;안명석
    • 화약ㆍ발파
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    • 제23권1호
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    • pp.1-8
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    • 2005
  • 화학류발파작업 가운데 장약, 전색, 결선작업은 많은 힘과 시간이 소요되어 작업자세에 따른 직업자의 불편도와 근부담이 증가하게 된다. 따라서 작업상 인적오류를 유발할 가능성이 높아진다. 이러한 원인은 작업자로 하여금 중요한 작업을 누락시키거나 근도반응을 일으켜 결국 사고와 재해로 연결되므로 이에 대한 체계적 연구가 요구된다. 화약발파작업에서 자세의 변화에 따라 발생할 수 있는 위험요인분석에는 OWAS, RULA, REBA, OSHA, JSI, NLE, TVAV, BLUE-X가 있으나 본 연구에서는 OWAS, RULA, REBA기법으로 평가하고 분석하였다. 그 결과 근골격계질환과 2차사고의 발생개연성이 큰 것으로 분석되었다.

A Procedure for Robust Evolutionary Operations

  • Kim, Yongyun B.;Byun, Jai-Hyun;Lim, Sang-Gyu
    • International Journal of Quality Innovation
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    • 제1권1호
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    • pp.89-96
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    • 2000
  • Evolutionary operation (EVOP) is a continuous improvement system which explores a region of process operating conditions by deliberately creating some systematic changes to the process variable levels without jeopardizing the product. It is aimed at securing a satisfactory operating condition in full-scale manufacturing processes, which is generally different from that obtained in laboratory or pilot plant experiments. Information on how to improve the process is generated from a simple experimental design. Traditional EVOP procedures are established on the assumption that the variance of the response variable should be small and stable in the region of the process operation. However, it is often the case that process noises have an influence on the stability of the process. This process instability is due to many factors such as raw materials, ambient temperature, and equipment wear. Therefore, process variables should be optimized continuously not only to meet the target value but also to keep the variance of the response variables as low as possible. We propose a scheme to achieve robust process improvement. As a process performance measure, we adopted the mean square error (MSE) of the replicate response values on a specific operating condition, and used the Kruskal-Wallis test to identify significant differences between the process operating conditions.

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자동화 비행시험기법에 의한 소형 무인헬리콥터의 파라메터 추정 (Parameter Estimation of a Small-Scale Unmanned Helicopter by Automated Flight Test Method)

  • 방극희;김낙완;홍창호;석진영
    • 제어로봇시스템학회논문지
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    • 제14권9호
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    • pp.916-924
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    • 2008
  • In this paper dynamic modeling parameters were estimated using a frequency domain estimation method. A systematic flight test method was employed using preprogrammed multistep excitation of the swashplate control input. In addition when one axis is excited, the autopilot is engaged in the other axis, thereby obtaining high-quality flight data. A dynamic model was derived for a small scale unmanned helicopter (CNUHELI-020, developed by Chungnam National University) equipped with a Bell-Hiller stabilizer bar. Six degree of freedom equations of motion were derived using the total forces and moments acting on the small scale helicopter. The dynamics of the main rotor is simplified by the first order tip-path plane, and the aerodynamic effects of fuselage, tail rotor, engine, and horizontal/vertical stabilizer were considered. Trim analysis and linearized model were used as a basic model for the parameter estimation. Doublet and multistep inputs are used to excite dynamic motions of the helicopter. The system and input matrices were estimated in the frequency domain using the equation error method in order to match the data of flight test with those of the dynamic modeling. The dynamic modeling and the flight test show similar time responses, which validates the consequence of analytic modeling and the procedures of parameter estimation.

R=1/2 Self-Doubly 조직 직교 길쌈부호를 찾는 효율적인 최적 스팬 알고리듬 (An Efficient Algorithm for finding Optimal Spans to determine R=1/2 Rate Systematic Convolutional Self-Doubly Orthogonal Codes)

  • 아타뱁도녀;서희종
    • 한국전자통신학회논문지
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    • 제10권11호
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    • pp.1239-1244
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    • 2015
  • 본 논문에서는 길쌈 Doubly 직교 부호의 최적 스팬을 찾기 위한 새로운 방법(Convolutional Self-Doubly Orthogonal, CDO)을 제안한다. 이 새로운 방법은 병렬 Implicitly-Exhaustive 탐색방법을 사용하는데, 이 방법으로 R =1/2 CDO 코드에 대한 최적의 스팬을 찾기 위해서 계산시간을 감소시키는 방법으로 동적 검색 공간 감소 방법을 적용했다. 제안된 알고리듬을 모의실험한 결과 기존의 방법에 비해서 계산시간이 감소되었고, 오류 정정 성능이 향상되었음을 확인하였다.

병원행정직원의 간병비 급여화에 대한 인식 (The Awareness on Medical Insurance on the Caregivers Cost for Hospital Administrative Personnel)

  • 황병덕;최령
    • 한국병원경영학회지
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    • 제19권2호
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    • pp.1-11
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    • 2014
  • The purpose of this study is to investigate awareness on medical insurance on the caregivers cost for hospital administrative staff and to provide the basic data for realization of legislation. The subjects were caregivers living in Busan, the survey was conducted from February 18 to March 9, 2013, 283 except for 17 copies of non-response and error response among a total of 300 questionnaires were analyzed. As a result, To improve the quality of care services, there were 51.8% of refresher training needs in refresher training items, 72.7% in favor of premiums increases in health insurance details, as for health insurance coverage subjects, patients' income were 32.0%, copayment for caregivers cost was 20.0%, which was 42.3%. Refresher training item, premiums increases, health insurance applied subjects, variables for copayment for care fee were related to medical insurance on the caregivers cost. On legislation on the medical insurance, systematic and standardized criteria should be provided to provide standardized curriculum for caregivers, to relieve patients and guardians of economic burden for caregivers cost and offer the stability of the cost.

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PLC 코드 작성을 위한 공정 분석 및 적용 방법 (The Process Analysis and Application Methods for PLC Code Programming)

  • 구락조;여성주;이강구;홍상현;박창목;박상철;왕지남
    • 산업공학
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    • 제21권3호
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    • pp.294-301
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    • 2008
  • Agile and flexible manufacturing systems make it mandatory that a control program should have features such as agility, flexibility, and reusability in order to run manufacturing unit smoothly. PLCs are the most frequently used control program in manufacturing systems. PLC programs are mostly programmed by subcontraction, which makes correction of code very difficult. As a result, it may cause delay during down time and ramp up time which leads to big loss of revenue and goodwill. To prevent delay during the times, this paper proposes systematic process analysis and application method for programmable logic controller like LLD (Ladder Logic Diagram). The proposed method uses modified human-error investing techniques for documentation and transforming technique to program LLD from the documentation. Furthermore, this paper demonstrates an example of piston mechanism to explain the proposed method.