• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.436-439
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• 2005

In general a square master and a dial gauge are used to measure the axis squareness on the spot. This method is a comparison measurement and its accuracy depends on the square accuracy wholly. Therefore the accuracy of a square master is very important and it is impossible that the accuracy of a square measurement is superior to the accuracy of a square master. In this paper, the new method of square measurement is proposed for measuring square without a square master and easily. This method is an absolute measurement by using a reversal method and can be used to measurement the accuracy of a square master.

• Korean Journal of Metals and Materials
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• v.47 no.5
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• pp.311-315
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• 2009

2-dimensional (2D) dopant profiling in semiconductor device was carried out by electron holography and scanning capacitance microscopy methods with the same multi-layered p-n junction sample. The dopant profiles obtained from two methods are in good agreement with each other. It demonstrates that reliability of dopant profile measurement can be increased through precise comparison of 2D profiles obtained from various techniques.

• Journal of Environmental Science International
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• v.22 no.2
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• pp.251-257
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• 2013

Discharge data examine the process of hydrologic cycle and used significantly in water resource planning and irrigation and flood control planning. It makes high quality discharge data, they carry out research on standard and method of discharge measurement, and equipment improvement. Now various flow meters are utilized to make discharge data in Korea. However, accuracy of equipment and exprerimental research data from measurement are not enough. ADCP(Acoustic Doppler Current Profiler) have been introduced and utilized for flow measurements since the end of 1980's. ADCP flow method is a formal method for flow measurement can easily applyd to relatively large rivers gradually recognized. This equipment can measure the non-contact three-dimensional velocity and water depth data very quickly and efficiently. Also, spatial and temporal resolution of the data is more accurate than any other flow measurement methods which measure flow rate by velocity - area measurement method. In this paper, the velocity is measured using various flow meter and verified the effectiveness by applying from the ADCP in Geum-river. Various flow meters which are med for discharge measurements are VALEPORT002, FLOW TRACKER, PRICE AA and ADCP. The average of five times flow measurement result by ADCP was $10.412m^3/s$, with a standard deviation of 0.68. The repeat test by ADCP and comparison between ADCP and other flow devices to verify the most import factor, flow measurement accuracy. In the result, repeat test of the ADCP showed similar values, flow values were similar to other velocity device results and the average error is 7.7%.

• Wind and Structures
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• v.31 no.1
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• pp.21-29
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• 2020

The wind field measurement of severe winds such as hurricanes (or typhoons), thunderstorm downbursts and other gales is important issue in wind engineering community, both for the construction and health monitoring of the wind-sensitive structures. Although several wireless data transmission systems have been available for the wind field measurement, most of them are not specially designed for the wind data measurement in structural wind engineering. Therefore, the field collection is still dominant in the field of structural wind engineering at present, especially for the measurement of the long-term and high-frequency wind speed data. In this study, for remote wind field measurement, a novel wireless long-term and high-frequency wind data acquisition system with the functions such as remote control and data compression is developed. The system structure and the collector are firstly presented. Subsequently, main functions of the collector are introduced. Also novel functions of the system and the comparison with existing systems are presented. Furthermore, the performance of this system is evaluated. In addition to as the wireless transmission for wind data and hardware integration for the collector, the developed system possesses a few novel features, such as the modification of wind data collection parameters by the remote control, the remarkable data compression before the data wireless transmission and monitoring the data collection by the cell phone application. It can be expected that this system would have wide applications in wind, meteorological and other communities.

• Journal of Veterinary Clinics
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• v.28 no.1
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• pp.108-112
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• 2011

In clinical settings, researchers often want to assess agreement between two measurements (or tests) of the same continuous variable. For example, when new point-of-care analyzer for testing blood glucose level were introduced clinicians need to compare results from standard or established laboratory method of measurement to those of new or point-of-care analyzer. The question in a method-comparison study would either of two different methods be used to measure the same variable equivalently. In this paper common misuse of statistical methodologies seen in the medical literatures such as correlation coefficient and paired t-test are discussed. The Bland-Altman technique has been widely used for this purpose and provides a graphic in presentation of the findings from a method-comparison study, with a mean value of measurement, this bias and the limits of agreement. For ease of application and interpretation of this technique we discussed the analysis procedure and illustrated with two worked examples. Finally, a number of alternative ways in which data can be analysed and reported in such studies were reviewed.

• Proceedings of the KIEE Conference
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• 1996.07c
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• pp.1895-1897
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• 1996

Lightning impulse voltage is essential to evaluate the insulation performance of electric power apparatus. Recently international standard (IEC-60) on high voltage measurement techniques are being revised. In the draft of this standard, a new calibration method is introduced and the accuracy of most industrial measuring systems is maintained by means of comparison test against the reference measuring systems. Comparison tests of dividers for chopped lightning impulse measurement were rallied out by KERI. The 700kV shielded resisitive divider with and without compensation element were done comparison test with 300kV PTB divider which have the similar charateristics as that were circulated among the laboratories. This paper reports on the calculation results of response charateristics obtained by EMTP and the comparison test results with chopped lightning impulse voltages from 150kV to 250kV. It is demonstrated that KERI are capable of realizing the idea in the revision of the IEC standand, that is, to establish traceability.

• 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.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.835-840
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• 2001

The new approach is a kind method of restoring temporary defect. Here, it is important for the defect not to occur problems of both local effect and global system. A basic concept is that it measures remaining prestress of PSC structures during the defect is restored. This study suggested new approach for measurement of remaining prestress. Two important results are obtained. First, safety problems, local stress concentration and global system, are very satisfied. Second, measurement value exists within error bound $\pm$ 1% in comparison with known value.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2004.10a
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• pp.126-132
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• 2004

The database design for the management of bridge measurement information is presented in this paper. To express the associated data generated during the whole process of ambient measurement efficiently, requirements analysis for database construction is performed. And to define objects and organize schema conceptual and logical design are performed, which convert data model into logical schema. Finally, physical design is performed using DDL(data defined language). This database is based on the object-relational data modeling approach that has rich expressive power and good reusability in comparison with the traditional entity-relational modeling.

• The KSFM Journal of Fluid Machinery
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• v.3 no.3 s.8
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• pp.25-30
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• 2000

Thermodynamic method of pump performance measurement calculates pump efficiency and flowrate by measuring fluid temperature increase and pressure rise through the pump. The theory of this method is investigated and precise comparison experiment with classical hydraulic method was conducted to verify the accuracy. Classical hydraulic pump performance measurement results and Yatesmeter results based on the thermodynamic method showed good agreement in measured performance.