• Title/Summary/Keyword: c control chart

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Development of a Software PLC for PC Based on IEC 61131-3 Standard (IEC 61131-3 표준을 따른 PC용 소프트웨어 PLC의 개발)

  • Lee, Cheol-Soo;Jeong, Gu;Lee, Je-Phil;Sim, Ju-Hyun
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.11 no.1
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    • pp.61-69
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    • 2002
  • This paper describes a converting algorithm between programmable languages of a software PLU. It is based on IEC 61131-3 standard and PC. The proposed control logic is designed by the software model and common element with data type, variables, POUs(program organization unit) and execution control unit commonly used within programmable languages of IEC 61131-3 Standard. The generation method of object file is proposed on five programmable language based on IEC 61131-3. It is represented as fo11ows; 1) the generation method using conversion algorithm from LD to IL with FBD(function block diagram), 2) the generation method using f code generation algorithm from SFC using the SFC execution sequence with FBD and ST(structured text). The proposed control logic generator was implemented by Visual C++ 6.0 and MFC on MS-windows NT 4.0.

A Study Of The Current-Diagram Method For Calculating Induction Motor Characteristics With Adjustable Frequency (가변주파수에 있어서 유도전동기특성의 도시산정법에 관한 연구)

  • Min Ho Park
    • 전기의세계
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    • v.18 no.4
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    • pp.22-30
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    • 1969
  • The development of the frequency convertors using semiconductors devices makes it possible to control the speed of A.C. motors easily. It is now economically feasible to provide them with power at adjustble frequency using silicon-controlled rectifier (or thyristor) inverters. In such a case, in order to operate an induction motor efficiently over a wide speed range, it must be supplied from a variable frecuency source of which frequency is adjustable over the speep range of the motor. It is desired to observe the changes in characteristics as primary current, torque-speed of induction moter etc. at any optional frequncy. Although the charactheristies can be obtained by means of the conventional methods they require very complicated precedures of calcuations. The Current Diagram Method in this paper suggests a new approach to simpler calcuations of the characteristics, using the motor constants at reference frequency. The conclusions of this study are summarized as follows: (1) The equations of stator current at adjusted frequency were derived to construct graphical chart and the current circle required for the Current Diagrm Method. (2) The radius, center of the current circle and the vector locus, the basis for calculating the characteristics, at any desired frequency could be easily determined with the aid of both the derived graphical chart and current circle at reference frequency. (3) The method was shown to be applicable to the various types of 3-phase induction motors and also dealt with its application to the split-phase, condenser motors.

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A Study of the Current-Diagram Method for Calculating Induction Motor Characteristics with Adjustable Frequency (가변주파수에 있어서 유도잔동기특성의 도식산정법에 관한 연구 제3보)

  • Min Ho Park
    • 전기의세계
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    • v.18 no.5
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    • pp.20-25
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    • 1969
  • The development of the frequency convertors using semiconductors devices makes it possible to control the speed of A.C. motors easily. It is now economically feasible to provide them with power at adjustable frequency using silicon-controlled rectifier (or thyristor) inverters. In such a case, in order to operate an induction motor efficiently over a wide speed range, it must be supplied from a variable frequency source of which frequency is adjustable over the speed range of the motor. It is desired to observe the changes in characteristics as primary current, torque-speed of induction motor etc. at any optional frequency. Although the characteristics can be obtained by means of the conventional methods, they require very complicated precedures of calculations. The Current Diagram Method in this paper suggests a new approach to simpler calculations of the characteristics, using the motor constants at reference frequency. The conclusions of this study are summarized as follows: 1) The equations of stator current at adjusted frequency were derived to construct graphical chart and the current circle required for the Current Diagram Method. 2) The radius, center of the current circle and the vector locus, the basis for calculating the characteristics, at any desired frequency could be easily determined with the aid of both the derived graphical chart and current circle at reference frequency. 3) The method was shown to be applicable to the various types of 3-phase induction motors and also dealt with its application to the split-phase, condenser motors.

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A Case Study on the Work Measurement of Hospital Foodservice by the Work Sampling Methodology (워크샘플링(Work Sampling)에 의한 병원급식의 작업측정 사례연구)

  • 차진아
    • Journal of Nutrition and Health
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    • v.24 no.6
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    • pp.547-559
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    • 1991
  • The purposes of this study were to : a)determine the percentage of labor activities expen-ded in various work functionsof hospital foodservice b)estimate the labor time utilized in each work functions c)investigate the overall work patterns of hospital foodservice and d)provide the basic data for effective labor control This study was conducted in two hospitals with 1300 and 1200 ed capacities and every employees of the dietary department were included in 10days work measurement. Work sampling methodology developed by Donaldson and Ostenso was modified and used for observing overall activities of hospital dietary department. Consistency of data and observa-tion period were verified by 3$\delta$ control chart and control chart. Observed data were satisfied with confidence level of 95% and confidence interval of $\pm$0.05, The results of this study were as follows: 1) The direct work function indirect work function and delay were 74.8%, 9.2%, 16.0% respectively with A hospital and 82.2% 7.2%, 10.6% respectively with B hospital 2) The productivity indices of direct work indirect work and delay were 9.05 min/meal 1.12 min/meal 1.94 min/meal respectively and total 12.11 minutes were utilized per meal served in A hospital and 10.72 min/meal 0.94 min/meal 1.38 min/meal respectively and total 13.04 minutes were utilized per meal served in B hospital 3) Full time equivalent(FTE) utilized in daily work of irect work indirect work and delay were 62.24 men 7.69 men 13.35 men respectively in A hospital and 64.09 men 5.63 men 8.22 men respectively in B hospital. 4) The contents of work activities of each employee group showed that delay time of the service personnel group was more than any other employee groups in both A hospital and B hospital 5) Examination of daily work schedule by time intervals showed that transportation work function was carried out all day so it is necessary to improve this work.

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Microbiological Hazard Analysis for HACCP System Application to fermented milk (발효유류의 HACCP 시스템 적용을 위한 미생물학적 위해 분석)

  • Park, Seong-Bin;Kwon, Sang-Chul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.1
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    • pp.438-444
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    • 2015
  • The aim of this research was to apply a HACCP system (Hazard Analysis Critical Control Point) to fermented milk. The main ingredients of fermented milk, work facilities and workers were obtained from a company named YD, which is located in Seobuk-gu, Cheonan-si between November 5 2013 to April 13, 2014. A manufacturing process chart was prepared by referring to the manufacturing process of fermented milk manufacturers in common. The manufacturing process chart was made with raw materials; Raw milk, High Fructose Corn Syrup, Oligosaccharides, Lactic Acid bacteria and Subsidiary ingredients, Warehousing of packaging materials, Storage, Input, Preheating, Mixing, Homogeneity, Sterilization, Precooling, Culture, Filtration, In packaging, Out packaging, Storage, and Consignment, as listed Table 1. The results of the microbiological hazard analysis on the raw materials was safe after sterilization($90^{\circ}C{\pm}5^{\circ}C$, $35{\pm}3min.$) On the other hand,a microorganism test of an environment and workers suggested that the microbiological hazard should be reduced through systematic cleaning and disinfection accompanied by improved personal hygiene based on hygienic education on workers and the management of microorganisms in air.

On the Estimation of the Process Deviation Based on the Gini's Mean Difference (지니(Gini)의 평균차이를 이용한 공정산포 추정)

  • 남호수;이병근;정현석
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.23 no.58
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    • pp.113-118
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    • 2000
  • Estimation of the process deviation is an important problem in statistical process control, especially in the control chart, process capability analysis or measurement system analysis. In this paper we suggest the use of the Gini's mean difference for the estimation of the c, the measure of the process deviation through a lots of simulations in various types of distributions. The Gini's mean difference uses the differences of all possible pairs of data. This point will improve the efficiency of estimation. In various classes of distributions, the Gini's mean difference shows good performance, in sense of bias of estimates or mean squared errors.

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Development of Control System Design Program Based on IEC1131-3 (IEC1131-3에 입각한 제어 시스템 설계 프로그램 개발)

  • Huh, Woo-Jung;Shin, Kyeong-Bong;Kim, Eung-Seok;Kim, Moon-Cheol;Park, Jung-Min;Kim, Sung-Tae
    • Proceedings of the KIEE Conference
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    • 1996.07b
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    • pp.1263-1265
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    • 1996
  • IEC1131-3 Specification of Programming Controller is established in 1994 and consists of 3 graphical languages and 2 textual languages. It is used in PLC and small scale controller because of its uniformity and extensibility. This paper describes Soft Logic Designer which is a graphical and textual programming editor for IEC1131-3 programming languages. Soft Logic Designer is developed with Object Orient Language, C++ under Microsoft Windows 95. It has two graphic editors for Sequential Function Chart and Function Block Diagram and one textual editor for Structured Text. Users can efficiently write high-level programs with mouse and menu buttons.

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Measurement of Sonobuoy Transmitting Antenna System for Anti-Submarine Warfare

  • Min Kyeong-Sik
    • Journal of electromagnetic engineering and science
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    • v.5 no.2
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    • pp.97-103
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    • 2005
  • This paper describes the measured results of sonobuoy transmitting antenna system for anti-submarine warfare (ASW). Since radiation pattern and power density depend on impedance matching between transmitting RF part and antenna with termination resistance, design of matching circuit is very important for sonobuoy system performance. Matching circuit is designed by Smith chart using control of L and C. In standing wave ratio(SWR) measurement using Network Analyzer, SWR of antenna with matching circuit observed 1.5 below at the assigned VHF band. It shows very excellent performance comparison with conversional product that is used for the same object. The measured vertical and horizontal radiation patterns are also shown the satisfaction of military specifications. A drop out of sonobuoy system on the sea is happened when angle of elevation direction is over 10 degrees, and it is conformed that it takes less than I second return to original signal level. The required electric power density is $83\;mW/m^2$ in the military specification, and measured electric power density is observed over average $110\;mW/m^2$ at all frequency bands.

프로그램 슬라이싱과 나씨-슈나이더만 차트를 이용한 구조적 프로그램의 이해를 위 한 도구 개발

  • 박승득;박만곤
    • Proceedings of the Korea Association of Information Systems Conference
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    • 1998.10a
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    • pp.157-164
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    • 1998
  • 본 논문은 원시 프로그램에 오류가 생겼을 때 신속한 오류검출, 소프트웨어의 유지 보수, 유연한 테스팅 등을 목적으로 하는 프로그램 슬라이싱과 원시 프로그램의 복잡한 베 어 흐름이나 데이터 흐름을 이해하고 프로그램이 테스팅 속도 향상과 오류위치를 파악하는 데 도움을 주는 구조적 순서도의 개념을 도압하여, C 언어데 대한 할당문(Assignment Statement)과 복합 제어 문(Compound Control Statement)으로 된 원시 프로그램의 입력 에 대해 프로시듀어(Procedure) 내에서의 구조적 순서도인 나씨-슈나아더만 차트 (Nassi-Shnei-derman Chart)를 자동 생성하고 실제 관심있는 변수에 대해 정적 슬라이싱 (Static Slicing)을 하는 도구를 개발함으로써 보다 빠르고 정확한 프로그램 구조의 이해에 도움을 주고자 한다.

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Teucrium polium L. Improved Heart Function and Inhibited Myocardial Apoptosis in Isolated Rat Heart Following Ischemia-Reperfusion Injury

  • Mahmoudabady, Maryam;Talebian, Faezeh Sadat;Zabihi, Narges Amel;Rezaee, Seyed Abdolrahim;Niazmand, Saeed
    • Journal of Pharmacopuncture
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    • v.21 no.3
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    • pp.159-167
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    • 2018
  • Objectives: Myocardial reperfusion is the only logical cure for ischemic heart disease. However, ischemic-reperfusion (I/R) injury is one of the underlying factors facilitating and accelerating the apoptosis in the myocardium. This study set to investigate the impact of Teucrium polium (TP) hydro-alcoholic extract on I/R induced apoptosis in the isolated rat heart. Methods: Isolated rat hearts were classified into six groups. The control samples were subjected to 80 min of perfusion with Krebs-Henseleit bicarbonate (KHB) buffer; in control-ischemia group, after primary perfusion (20 min) the hearts were exposed to global ischemia (20 min) and reperfusion (40 min). Pretreated groups were perfused with $500{\mu}M$ of vitamin C and various TP concentrations (0.5, 1, 2 mg/ml) for 20 min, and then the hearts were exposed to ischemia and reperfusion for 20 min and 40 min, respectively. Cardiodynamic parameters including rate pressure product (RPP), heart rate (HR), the maximum up/down rate of left ventricular pressure (${\pm}dp/dt$), left ventricular developed pressure (LVDP), and coronary artery flow (CF) were achieved from Lab Chart software data. The Bax and BCl-2 gene expressions were measured in heart samples. Results: Hearts treated with TP extract and vit C represented a meaningful improvement in cardiac contractile function and CF. The overexpression of Bcl-2, downregulation of Bax, and improvement of apoptotic index (Bax/Bcl-2) were observed in pretreated TP extract and vit C hearts. Conclusion: The TP extract was found to ameliorate the cardiac function in the reperfused myocardium. Also, it can hinder apoptotic pathways causing cardioprotection.