• Title/Summary/Keyword: accidental error

Search Result 20, Processing Time 0.028 seconds

Improved performance of a linear pulse motor with repetitive positioning control

  • Sawaki, Jun;Matsuse, Kouki;Yamamoto, Shu
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1996.10a
    • /
    • pp.389-392
    • /
    • 1996
  • We propose a method to improve repeatability positioning precision of a linear pulse motor. By using this method the systematic error which may make the precision worse can be suppressed easily. And also we show that Power OP-Amp drive system enables the accidental error to be suppressed in comparison with PWM control drive system using IGBT inverter. As a result of the suppression of systematic and accidental error, improved performance of a linear pulse motor with repetitive positioning control is shown by experimental results.

  • PDF

Landmarks in The Skull for Stereotactic Radiotherapy

  • Hiroki, Ohtani;Toraji, Irifune;Etsuo, Kunieda;Hidetoshi, Saitoh;Masahiro, Fukushi;Tsuguhisa, Katoh
    • Proceedings of the Korean Society of Medical Physics Conference
    • /
    • 2002.09a
    • /
    • pp.144-145
    • /
    • 2002
  • Stereotactic radiotherapy is required to irradiate a small tumor accurately. The radiotherapy showing improves when making an accidental error little boundlessly. It is performed according to treatment planning that is established by the outside landmark of head. At present, when stereotactic radiotherapy for a head is done, the Leksell Flame is fixed on the head, and positioning based on the point and so on which it is in that fixed implement is performed. However, there are problems on the method done at present in the point such as reappearance when the fractionated irradiation method in which the Leksell Flame is removed and installed at every treatment is done because there are landmarks outside the head. Landmarks in the skull were decided, and that precision was examined for the purpose of the improvement of the radiation therapeutic gain. Linac-graphy with longitudinal and lateral view were taken with 6 MV photon beams. A distance to base point inside the skull, each film measured the angle from a center of the small irradiation field, and comparison was done. From the results, a large accidental error wasn't seen as a result of the measurement by every film. Stereotactic radiotherapy for a head treatment had an accidental error of about several millimeters when treatment positioning was done. Therefore, it was thought that there was no problem about an accidental error to arise by putting a landmark in the skull. And, because an accidental error was easy to discover, we thought that modification could be done easily. It was suggested that a landmark in the skull on thus study were useful for improvement of stereotactic radiotherapy.

  • PDF

가우스의 오차론에 근거한 정규분포 배경의 역사적 고찰

  • 구자흥
    • Journal for History of Mathematics
    • /
    • v.12 no.1
    • /
    • pp.1-12
    • /
    • 1999
  • The first part of this thesis discusses the types and the properties of errors, one of which makes up systematic errors of measurements, removable by detecting their causes, the other errors of accidental causes which can not be removed. The final part of this thesis deals with the historical background of the Gaussian distribution by Hershel, Hagen, Laplace and Gauss from the late 18th century to the early 19th century. It can be concluded that the accidental idea and the treatment of accidental error distribution by Gauss Is the best one based on the assumption that the most probable value of true value is the arithmetic mean of data, obtained by repeated measurements of a given quantity.

  • PDF

A Case of Sprinkler Non-Working by Programming Error (프로그래밍 오류에 의한 스프링클러 미작동 사례)

  • Seo, Young-Il;Cho, Young-Jin;Moon, Byung-Seon;Park, Jong-Jin;Park, Jong-Chan;Park, Nam-Kyu
    • Fire Science and Engineering
    • /
    • v.22 no.2
    • /
    • pp.116-120
    • /
    • 2008
  • According to the Fire Services Act revised in 2005, it has been required to set up sprinkler systems to all floors to the newly builded apartments having above 11 floors. But, according to the Fire Services Act before 2005, it had been required to set up sprinkler systems from 16 floors to the top floors to the apartments having above 16 floors. This case is the accident that a victim was dead by the fire which is inferred as an accidental fire by a cigarette butt in a 17th floor apartment unit in an apartment having 17th floors and that the bereaved family called in question why the sprinklers non worked at the fire. Through the field investigation, we checked that the sprinklers worked well when the fire detectors at the 16th floor of the apartment were operated and that the sprinklers non worked when the fire detectors at the 17th floor of the apartment were operated. We made clear that the cause of the sprinkler non-working at the 17th floor is the programming error of the sprinkler controller.

An Analysis of Human Factor and Error for Human Error of the Semiconductor Industry (반도체 산업에서의 인적오류에 대한 인적요인과 과오에 대한 분석)

  • Yun, Yong-Gu;Park, Beom
    • Proceedings of the Safety Management and Science Conference
    • /
    • 2007.04a
    • /
    • pp.113-123
    • /
    • 2007
  • Through so that accident of semiconductor industry deduces unsafe factor of the person center on unsafe behaviour that incident history and questionnaire and I made starting point that extract very important factor. It served as a momentum that make up base that analyzes factors that happen based on factor that extract factor cause classification for the first factor, the second factor and the third factor and presents model of human error. Factor for whole defines factor component for human factor and to cause analysis 1 stage in human factor and step that wish to do access of problem and it do analysis cause of data of 1 step. Also, see significant difference that analyzes interrelation between leading persons about human mistake in semiconductor industry and connect interrelation of mistake by this. Continuously, dictionary road map to human error theoretical background to basis traditional accidental cause model and modern accident cause model and leading persons. I wish to present model and new model in semiconductor industry by backbone that leading persons of existing scholars who present model of existent human error deduce relation. Finally, I wish to deduce backbone of model of pre-suppression about accident leading person of the person center.

  • PDF

Body Shape Measurement Using Stereo Photo (입체사진을 위용한 인체형상계측)

  • Choe, Hyeok-Ju;Seong, Gyeong-Hwa;Lee, Hyeon-Jik
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.22 no.5
    • /
    • pp.664-675
    • /
    • 1998
  • The purpose of this study was to isolate the observational error included in plane photogrammetric data and suggest more accurate and suitable method for body shape measurement. Three experiments were carried out in this study. First of all, the variables which can be obtained from photogrammetric method were selected among the data which can be measured improperly by direct measurement or showing large deviations between the samples. Secondly, the height, the width and the depth of 50 subjects were measured by plane photogrammetry. The result showed that plane photogrammetric data contain significant observational error even for the same variables, as the angle of which photos had been taken changes. Therefore, in order to reduce the observational error and to measure the human body accurately, three-dimensional measurement, stereo photogrammetry was employed in the last experiment. As it is important to isolateonly the observational error by plane photogrammetry and to exclude the accidental error caused by movement of human body subject, body shape model(manikin) was used as subject. The result showed that the average observational error by plane photogrammetry was more than 4 cm in the height, 0.85-1.29cm in the width and 0.49cm in the depth. In conclusion, it is not adequate to use the height obtained from plane photogrammetric data as human body measurement data. And the width and the depth should be used cautiously, even though they are relatively less significant, the error still can make some difference on clothing construction.

  • PDF

Application of ANFIS for Prediction of Daily Water Supply (상수도 1일 급수량 예측을 위한 ANFIS적용)

  • Rhee, Kyoung-Hoon;Kang, Il-Hwan;Moon, Byoung-Seok
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.14 no.3
    • /
    • pp.281-290
    • /
    • 2000
  • This study investigates the prediction of daily water supply, which is a necessary for the efficient management of water distribution system. ANFIS, namely artificial intelligence, is a neural network into which fuzzy information is inputted and then processed. In this study, daily water supply was predicted through an application of network-based fuzzy inference system(ANFIS) for daily water supply prediction. This study was investigated methods for predicting water supply based on data about the amount of water which supplied in Kwangju city. For variables choice, four analyses of input data were conducted: correlation analysis, autocorrelation analysis, partial autocorrelation analysis, and cross-correlation analysis. Input variables were (a) the amount of water supply, (b) the mean temperature, and (c) the population of the area supplied with water. Variables were combined in an integrated model. Data of the amount of daily water supply only was modelled and its validity was verified in the case that the meteorological office of weather forecast is not always reliable. Proposed models include accidental cases such as a suspension of water supply. The maximum error rate between the estimation of the model and the actual measurement was 18.46% and the average error was lower than 2.36%. The model is expected to be a real-time estimation of the operational control of water works and water/drain pipes.

  • PDF

Estimation of Mass Error in the Simulation of Mixing of Instantaneously Released Pollutants (순간 유입된 오염물질의 혼합 모의 시 질량 오차 산정)

  • Lee, Myung Eun;Seo, Il Won
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.28 no.5B
    • /
    • pp.475-483
    • /
    • 2008
  • 2D finite element model for analysis of transport of accidentally released pollutants in the flow was developed by SUPG method, and the mass balance of this model was checked though two example problems: line source and point source problem in the straight channel and unidirectional 2D flow field, respectively. All the test cases were simulated with both SUPG and conventional Galerkin method to compare the accuraccy of the numerical mass balance. Test results show that the model with SUPG can adequately conserve the released mass though simulation than the model using Galerkin method, so the developed model verified to be appropriate to solve this accidental mass release problem.

The Application of Ecological Interface Design Methodology for Digitalized MCR in Nuclear Power Plant

  • Ra, Doo Wan;Cha, Woo Chang
    • Journal of the Ergonomics Society of Korea
    • /
    • v.32 no.1
    • /
    • pp.1-7
    • /
    • 2013
  • Objective: This study proposes the application of Ecological Interface Design(EID) method that is effective for situation awareness in digitalized environment. Background: While cognitive interface design method such as Information Rich Display(IRD) is simply focused on existing information for user, EID method helps users' resource to be solved to higher ion task such as diagnostic and problem solving. Method: Using EID method based on Work Domain Analysis (WDA), it was analyzed and designed for Steam Generator(SG) Water Level control process in a digitalized Main Control Room of Nuclear Power Plant. Proposed EID example is evaluated through interviews by expert & operator. Results: The result of expert & operator showed that EID display might give an aid for operator's decision. Conclusion: The results can reduce critical accidental damage that occurred due to cognitive load and so critical human error. Application: This study may be impact on situation awareness study for digitalized interface design.

Prediction of Daily Water Supply Using Neuro Genetic Hybrid Model (뉴로 유전자 결합모형을 이용한 상수도 1일 급수량 예측)

  • Rhee, Kyoung-Hoon;Kang, Il-Hwan;Moon, Byoung-Seok;Park, Jin-Geum
    • Journal of Environmental Impact Assessment
    • /
    • v.14 no.4
    • /
    • pp.157-164
    • /
    • 2005
  • Existing models that predict of Daily water supply include statistical models and neural network model. The neural network model was more effective than the statistical models. Only neural network model, which predict of Daily water supply, is focused on estimation of the operational control. Neural network model takes long learning time and gets into local minimum. This study proposes Neuro Genetic hybrid model which a combination of genetic algorithm and neural network. Hybrid model makes up for neural network's shortcomings. In this study, the amount of supply, the mean temperature and the population of the area supplied with water are use for neural network's learning patterns for prediction. RMSE(Root Mean Square Error) is used for a MOE(Measure Of Effectiveness). The comparison of the two models showed that the predicting capability of Hybrid model is more effective than that of neural network model. The proposed hybrid model is able to predict of Daily water, thus it can apply real time estimation of operational control of water works and water drain pipes. Proposed models include accidental cases such as a suspension of water supply. The maximum error rate between the estimation of the model and the actual measurement was 11.81% and the average error was lower than 1.76%. The model is expected to be a real-time estimation of the operational control of water works and water/drain pipes.