• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.4
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• pp.561-571
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• 2001

The standard uncertainty of flowrate measurement is obtained by combining that of independent variables. Gravimetric and volumetric method were applied to determine the flowrate and the standard uncertainties of flowrate measurement by both methods were evaluated in accordance with the procedure recommended by International Organization for Standardization. The combined standard uncertainties of determining the flowrate were estimated from the sensitivity coefficient and the standard uncertainty of independent variables. For practical application, the methods for evaluating and expressing uncertainty in flow measurement were discussed. It was found that the uncertainties of the weighing and time measurement in gravimetric method, the volume and time measurement in volumetric method have dominant influence on that of flowrate measurement. With the quantitative analysis of the sensitivity coefficient, the contribution of the each variable uncertainty to the combined standard uncertainty of flowrate measurement is shown clearly.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.9 no.2
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• pp.35-41
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• 2010

The balance coefficients between telecommunication lines are specified in the technical standard and the power induction computation method varies in the order of 100 times in magnitude according to the amount of impedance. The results of actual balance measurements, differing from time to time with the measurement circuit or increasing proportionally as the induction voltage increases, appeared as a measurement error because of not using the standard measurement circuit. This article investigates such errors and proposes the use of a standard balance measurement circuit and a measurement device impedance under the domestic notification standard and the ITU-T international standard.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.33 no.1
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• pp.3-5
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• 2023

Objective: This study introduces exposure concentrations of time-weighted average standard (TWA) evaluation and short-time exposure standard (STEL) evaluation for trichloroethylene in the cleaning process. Methods: Trichloroethylene measurement was conducted according to the KOSHA Guide (A-24-2019) method. It was carried out twice. Results: As a result of the first measurement, TWA concentration exceeded 4 times the exposure standard and STEL concentration exceeded 16 times, but the inaccuracy and breakthrough of the collection time could not be considered, so the second measurement was conducted. The second measurement result was lower than the first measurement result, but exceeded the exposure standards (TWA, STEL). Conclusions: We were able to confirm that the exposure level of workers in the cleaning process using trichloroethylene exceeded the exposure standard. And it is also considered necessary to grasp the approximate concentration using a detector tube in the preliminary survey.

• Proceedings of the ESK Conference
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• 1997.04a
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• pp.247-255
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• 1997

In this study, the comparison of the basic human body measurement definitions and anthropometric terms between the Korean Standard and the International Standard. Measurement definitions, measurement method and measurement terms of the international standard ISO 8559, 7250 were compard with the KSRI-88-103-IR. We have tried to suggest the new methods and new terms such as eye height, waist height, arm length.

• Journal of the Korean Society for Heat Treatment
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• v.12 no.4
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• pp.294-302
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• 1999

Evaluation of Brinell standard hardness tester was carried out to secure its application as a national standard for Brinell hardness. Accuracies and reliabilities in load application, indenter diameter and indentation measurement were tested through evaluation of these components. The accuracies of load application for various loading conditions were within the limit of ISO and KS specifications. Errors in the indentation measurement due to the difference in personnel characters were successfully removed by utilising automatic indentation measurement system. In overall, the tester and the indentation measuring system were found to be eligible as a national standard of Brinell hardness.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.2 no.2
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• pp.39-51
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• 1979

In introducing and applying the budget management system, the question of how to establish management structure(skelton) representing budget management responsible unit is significantly related to the degree of accuracy and analysis on the performance measurement of standard work unit. We have the following rational process of establishing performance measurement of budget management System ; 1) Standardization of work method 2) Establishment of management structure 3) Institution of budget management system. Especially, this system is based on a premise of efficiency of objectives management, it is assumed that performance measurement in the standard work unit must be enforced according to the basis and categories of performance evaluation based on the evaluating work unit. Therefore, most of all, the following three detail questions(subjects) are to be determined in order to rationalize these above principles to a maximum possible extent of performance measurement system. First, we established respective performance standard unit with respect to such detailed work unit, performance standard unit of which were accurately applicable directly from using the budget ana objectives account data and their supplementary data of the work measurement techniques. Second, by using the above mentioned question, over all evaluation and suggestion are made based on the study of the recording for each work unit development, budget management and production nit (volume of production) Third, the measurement of performance of budget management system is based on the principle of standard work unit, compared with the standard basis and actual work unit by period and activities unit and calculated percentage effectiveness according to the above procedure. and so evaluated the efficiency of performance measurement on the budget management system.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.60 no.1
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• pp.37-44
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• 2011

HSPA(High Speed Packet Access)/HSPA+ is a combined 3GPP(Third Generation Partnership Project) standard of HSDPA(High Speed Downlink Packet Access) and HSUPA(High Speed Uplink Packet Access). The standard can provide the high speed multimedia service against the 3GPP release 99 standard. In order to test the 3GPP HSPA/HSPA+ terminal performance, the measurement hardware is required for the evaluate the transmitted signal of HSPA/HSPA+ terminals. Agilent Technologies and Innowireless produce the measurement equipments for HSPA/HSPA+ terminals. Generally speaking, the receiving algorithms in normal modems cannot be used directly to the measurement system due to the lack of the algorithm accuracy. In this paper, we propose the new receiver algorithm for precise measurement of 3GPP HSPA/HSPA+ terminal signal, and implement measurement functionality for performance measurement of the 3GPP HSPA/HSPA+ terminal by using software. The proposed 3GPP HSPA/HSPA+ signal measurement algorithm can be used for the commercial system through code execution speed optimization.

• 한국연소학회:학술대회논문집
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• 2014.11a
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• pp.143-144
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• 2014

The demand of diesel engine on the construction equipment has been rapidly increased because of thermal efficiency and power. But some of the construction equipment is imported from other country, since the their demands are not so large as compared with the other construction equipment. The imported construction equipments will be tested for emission with standard measurement mode. This study was conducted to measure emission characteristics of the construction equipment with changed standard measurement experimentally.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.1
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• pp.73-78
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• 2010

Estimation of tensile properties measurement uncertainty of material was carried out. Sources of uncertainty affecting the measurement of tensile properties were classified and analyzed. The models for uncertainty evaluation of measurands to be determined from tensile test, such as elastic modulus, yield strength and tensile strength, were suggested and derived from the mathematical relations, corresponding to the respective measurands, and the measuring quantities by calculating each sensitivity coefficient of the quantities. Based on these models, the uncertainty of the tensile properties was evaluated from the experimental data of SUS316LN determined according to ISO 6892.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.1
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• pp.53-60
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• 1995

The aims of this study are to evaluate the measurement capability of the electromagnetic power and to understand the current state of standard maintanance of the eight participants among the thirteen national calibration and test organizations. The calibration factors were measured at six test frequencies, 50, 100, 500, 1000, 5000, 10000 MHz by organizations and KRISS on the basis of round robin test. The results were analyzed by calculating the standard deviation of the measured values from the standard values. The analysis shows good agreement within 1.0% for all participants at the measurement frequencies. Therefore, the measurement capability of all participants is good in the frequency range of 50 MHz to 10 GHz. For the four participants which specified standard deviations of repeated measurements in their reporst, the total uncertainties is less than 1.9% at the measurement frequencies.