• Title/Summary/Keyword: calculation chart

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Detection of Changes of the Population Fraction Nonconforming in the p Control Chart (p관리도의 불량률의 변화 탐지)

  • Chang, Kyung;yang, Moon-Hee
    • Journal of Korean Society for Quality Management
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    • v.25 no.3
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    • pp.74-85
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    • 1997
  • In this paper we calculate the subgroup size necessary for detecting the change of percent defective with several detection probabilities for orginal population fraction nonconforming p, changed population fraction nonconforming $p^*$, and the ratio k=$p^*$/p in the usage of p control charts. From our calculation we can know the error level of normal a, pp.oximation in detection probability calculation and recommend the subgroup size with lower error levels of normal a, pp.oximation, and then we show the reasonable subgroup size necessary for p, $p^*$, k, and the detection probability of the change of fraction nonconforming in a process. The information that we here show in tables will be useful when p control chart users decide the subgroup size in the p control chart users decide the subgroup size in the p control chart.

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Calculation of Tissue-Air Ratios(TAR) in Irregularly shaped Field for Co-60 Gamma Radiation (CO-60 감마선에 대한 부정형조사면의 조직공중선량비 (TAR) 계산)

  • Ji Young-Hoon
    • The Journal of Korean Society for Radiation Therapy
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    • v.3 no.1
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    • pp.27-36
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    • 1989
  • In order to calculate the dose on each interest point in five types of irregularly shaped fields used commonly in radiotherapy, the tissue-air ratios (TAR) in these fields for Go-60 gamma radiation were calculated using the newly devised SAR-chart. The TARs calculated from newly method of using the SAR-chart, computer method and approximation method at the interest point were compared to the TARs obtained from measurement. The result are as follows; In case of the interest points on central axis the calculated TARs in irregularly shaped fields by the above mentioned methods were well agreed within the error of $1\%$, whereas for the interest points on off-axis the calculated TARs were resulted in the maximum errors of $2.4\%,\;2.3\%$ and $8.8\%$ respectively. From these results, the accuracy of calculation method of using the SAR-chart was comfirmed.

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A Study on Optimal Equipment Fleet focused on Pusher-loaded Scrapers in Earthmoving Operation (토사운반 공정의 스크레이퍼 중심 최적 장비조합에 관한 연구)

  • Lee, Hyung-Guk;Son, Chang-Baek;Lee, Dong-Eun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2012.11a
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    • pp.39-42
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    • 2012
  • Pusher-Loaded Scrapers are important construction equipment for large earthmoving operations. Production rates of a Pusher-Loaded Scraper vary greatly in accordance with the temperature or elevation, the equipment performance, haul speed, haul-road conditions, the method of loading, and Number of scrapers per one pusher. Determining of most economical scrapers fleet regarding the size of equipment, model name, and number of scrapers demands time-consuming calculation because it needs to reference of varied performance charts or tables and repeat complicated calculation. In this study, decision-making support system for the Optimal Pusher-loaded Scrapers Fleet is suggested for the purpose of calculating easily and handling effectively variables which are changed depend of the work conditions. The prototype of this program is developed using MATLAB. And the Database of Pusher-loaded Scraper embodies Performance chart & Retarder chart, soil properties, and calculation-support table.

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A Study on the Development of Sunlight Analysis Program "SunChart" (일조해석 프로그램, SunChart 개발에 관한 연구)

  • Shin, U-Cheul;Jang, Moon-Seok;Baek, Nam-Choon
    • Journal of the Korean Solar Energy Society
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    • v.22 no.4
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    • pp.10-17
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    • 2002
  • This study aims to develop the analysis tool that assesses the sunlight at any given point of a window or solar collector array shaded by surrounding obstacles. The development of this software, named SunChart, focused to the user-friendliness and the reliability. This SunChart can calculate the solar radiation as well as shading on the certain face. The calculation results by SunChart show by both numerically and graphically and are in a good agreement with ones obtained from "Sunrise Sunset" developed at Korea Astronomy Observatory and from TRNSYS.

Air Fuel Ratio and Calculation According to Fuel Composition (III) -Comparison of Various Calculation Method- (연료 조성에 따른 공연비 산정 (III) - 공연비 계산방식간의 상호 비교 -)

  • Park Chanjun;Ohm Inyong
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.28 no.10
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    • pp.1147-1154
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    • 2004
  • This paper is the third of several companion papers which compare the method of Air-Fuel ratio determination. In the previous works, Eltinge chart was expanded to arbitrary fuel composition as a reference exhaust composition. The compensation of unburned hydrocarbon in Eltinge chart and comparison of Spindt and Eltinge method were also discussed. In addition to Eltinge and Spindt's one, however, there are many methods which calculate Air-Fuel ratio from exhaust emission. Among these methods, carbon balance and oxygen balance are widely used in practice. In some applications, linear formula from statistical method is being used in the field due to its simplicity and convenience. In this paper, these various methods are evaluated and compared with Eltinge results and new linear formula is proposed for the gasoline fuel. The results show that the corrected carbon balance equation has excellent agreement with Eltinge and Spindt's one. On the other hands, the oxygen-balanced formula has a limitation according to the mixture state and AFR. For gasoline fuel, newly proposed linear equation has good compatibility with Eltinge and Spindt up to AFR 17.

A Study of Statistical Tools Application - Evaluation of Process Capability - (통계적기법(統計的技法) 활용(活用)에 관(關)한 연구(硏究) - 공정능력평가(工程能力評價)를 중심(中心)으로 -)

  • Seong, Won-Yong;Jung, Soo-Il
    • Journal of the Korea Safety Management & Science
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    • v.10 no.2
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    • pp.195-203
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    • 2008
  • The purpose of this study is to develop a guideline of process capability evaluation and to apply this guideline improving the quality of products, especially in the small and medium enterprises. In this study we deal in the concept of process capability evaluation, the calculation of process capability index, and the application of a case study. Man must compare the state of process with the standards in evaluating of the process capability. Control chart can be used as a yardstick for judgement for the long term period and the distribution shape of histogram for the short term period. Man should regard to the significant figure by the calculation of process capability index.

Dose Distribution&Calibration in HDR Intracavitary Irradiation for Uterine Cervical Cancer (자궁경부암의 강내치료를 위한 선량측정)

  • 김진기;김정수;김형진;권형철
    • Progress in Medical Physics
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    • v.6 no.1
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    • pp.13-18
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    • 1995
  • Dose distribution of HDR-RALS source represents an inverse square law as the distance. Difference of measurement value and calculation value according of brachytherapy. Therefore, in HDR-RALS dose calibration and calculation have an important effect in treatment of uterine cervical cancer and absorbed dose of interesting points. In intracavitary therapy, particula attention is paid for precise determination of the doses to be applied. In this report, we have discussed that the calibration of a HDR-RALS, differences between calculation dose use of isodose chart and measurement in rectum. Dose rate calibration of radiation sources are obtained from air kerma and Г factor with calibraed ion chamber for cobalt source. and used semiconductor detector for compared with measurement in phantom. Eighteen patients were treated with a HDR-RALS for intrcavitarty irradiation (ICR) using a cobalt-cesium source. Repoductivity of dose measurements were 0.3 -1.1% in phantom. The means of dose distribution was -6- +21% between calculation of isodose chart and measurement of recyum, and was same mean value upper 6.3% in measurement value than calculation does.

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Determination of Air Fuel Ratio according to Fuel Composition (I) -Eltinge Chart as a Reference Exhaust Composition- (연료 조성에 따른 공연비 산정 (I) -기준 배기 조성으로서 Eltinge 차트-)

  • Ohm, In-Yong;Park, Chan-Jun
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.27 no.11
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    • pp.1548-1562
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    • 2003
  • This paper is the first of several companion papers which compare the methods of Air-fuel ratio determination. There are many methods which calculate Air-Fuel ratio from exhaust emission. Most of them are based on the simple chemical equations, which use balance of atom, and the error of the calculation is negligible as far as the instrumentation accuracy is guaranteed. They assume homogeneous mixture and complete combustion to the extent of oxygen availability. Because of these simple assumptions, they cannot offer the information about the fuel distribution state and the malfunction of instrument. For these limitations, Eltinge offered new one based on stricter mathematical model. This result coincides with the others very well and gives more information about the mixture state and instrumentation. Consequently this might be a general solution for Air-fuel ratio determination and exhaust composition. The objects of the calculation, however, were not commercial fuels except gasoline and the compensation method of unburned hydrocarbon was not appropriate to recent analyzer. Moreover he did not consider the fuel which contains oxygen, such as methanol, ethanol and blend of gasoline-alcohol. In this paper, Eltinge chart is expanded to the arbitrary fuel composition as the reference exhaust compositions for the purpose of further discussions about Air-fuel ratio determination methods and the charts fur gasoline, diesel, methanol, M85, liquefied petroleum gas(LPG), natural gas(NG), propane, butane are illustrated.

A Cosideration on Physical Aspects in Teleradiotherapy Chart QA (원격방사선치료 기록부의 QA 에서 물리적 측면의 고찰)

  • 강위생;허순녕
    • Progress in Medical Physics
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    • v.10 no.2
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    • pp.95-101
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    • 1999
  • The aims of this report are to classify the incorrect data of patients and the errors of dose and dose distribution observed in QA activities on teleradiotherapy chart, and to analyze their frequency. In our department, radiation physicists check several sheets of patient chart to reduce numeric errors before starting radiation therapy and at least once a week, which include history, port diagram, MU calculation or treatment planning summary and daily treatment sheet. The observed errors are classified as followings. 1) Identity of patient, 2) Omitted or unrecorded history sheet even though not including the item related to dose, 3) Omission of port diagram, or omitted or erroneous data, 4) Erroneous calculation of MU and point dose, and important causes, 5) Loss of summary sheet of treatment planning, and erroneous data of patient in the sheet, 6) Erroneous record of radiation therapy, and errors of daily dose, port setup, MU and accumulated dose in the daily treatment sheet, 7) Errors leading inexact dose or dose distribution, errors not administerd even though its possibility, and simply recorded errors, 8) Omission of sign. Number of errors was counted rather than the number of patients. In radiotherapy chart QA from Jun 17, 1996 to Jul 31, 1999, no error of patient identity had been observed. 431 Errors in 399 patient charts had been observed and there were 405 physical errors, 9 cases of omitted or unrecorded history sheet, and 17 unsigned. There were 23 cases (5.7%) of omitted port diagram, 21 cases (5.2%) of omitted data and 73 cases (18.0 %) of erroneous data in port diagram, 13 cases (3.2 %) treated without MU calculation, 68 cases (16.3 %) of erroneous MU, 8 cases (2.0%) of erroneous point dose, 1 case (0.2 %) of omitted treatment planning summary, 11 cases (2.7%) of erroneous input of patient data, 13 cases (3.2%) of uncorrected record of treatment, 20 cases (4.9%) of discordant daily doses in MU calculation sheet and daily treatment sheet, 33 cases (8.1%) of erroneous setup, 52 cases (12.8%) of MU setting error, 61 cases (15.1%) of erroneous accumulated dose. Cases of error leading inexact dose or dose distribution were 239 (59.0 %), cases of error not administered even though its possibility were 142 (35.1 %), and cases of simply recorded error were 24 (5.9 %). The numeric errors observed in radiotherapy chart ranged over various items. Because errors observed can actually contribute to erroneous dose or dose distribution, or have the possibility to lead such errors, thorough QA activity in physical aspects of radiotherapy charts is required.

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High precision Gating Algorithm for Predictive Current Control of Phase Controlled Rectifier (위상제어 정류기의 예측전류제어를 위한 새로운 고정밀 게이팅 알고리즘)

  • 정세종;송승호
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.53 no.3
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    • pp.206-211
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    • 2004
  • In phase controlled rectifier, it's been known that a fast response is achieved by predictive current control without any overshoot. The frequent sampling period is essential to improve the firing accuracy in conventional predict current control. However, improving the firing accuracy if difficult to reduce the period of sampling efficiently because current sampling and predictive current control is carried out in every period and the ON-OFF current control is performed by comparing two different one. To improve the firing accuracy at the predictive current control, the calculated firing angle is loaded into the high-accuracy hardware timer. So the calculation of exact crossing point between the predictive and actual current is the most important. In this paper, the flow chart for proposed firing angle calculation algorithm is obtained for the fastest current control performance in transient state. The performance of proposed algorithm is verified through simulations and experiments.