• Land and Housing Review
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• v.9 no.4
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• pp.33-42
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• 2018

As a radiant heating panel gets more popularity, the need to study on evaluation method of thermal output of the panel also becomes increasing. Generally, the chamber using method is applied to evaluate the thermal output through an experiment. However, the chamber using method cannot be used due to the limitations on space and cost. EN1264 addresses the test equipment to evaluate the thermal output by using simpler experimental setup, and introduces application method in detail. However, there is not enough description of control methods to meet the experiment condition, and it is difficult to meet this when practical experiment. Therefore, this paper analysed the control error factors of when the thermal output experiment is performed. When EN1264 method is applied to evaluate the thermal output of the radiant floor heating panel, the error factor which is caused by the characteristic of test equipment cannot be removed by the control methods of chamber using method. In addition, the error factor can be occurred at the element which is located out of the control system. These possible error factors are defined as the characteristic error factors.

• Journal of Wind Energy
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• v.9 no.4
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• pp.9-15
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• 2018

In a previous study, a technique for measuring wind speed and direction by using a roll-rotating three-axis ultrasonic anemometer was proposed and verified by wind tunnel tests. In the tests, instead of a roll sensor, roll angle was trimmed to make no up flow in the transformed wind speeds. Verification was done in point of the residual error of the rotation effect treatment. In this study, roll angle was measured from the roll motor encoder and the transformed wind speed and direction on the test section axis were compared with the ones provided to the test section. As a result, up to yaw $20^{\circ}$ at a wind speed of 12 m/sec or over, the RMS error of wind speed was within the double of the ultrasonic anemometer error. But at yaw $30^{\circ}$, it was over the double of the ultrasonic anemometer error. Regardless of wind speed, at yaw $20^{\circ}$ and $30^{\circ}$, the direction error was within the double of the ultrasonic anemometer error. But at yaw $10^{\circ}$ or less, it was within the error of the ultrasonic anemometer itself. This is a very favorable characteristic to be used for wind turbine yaw control.

• Proceedings of the Safety Management and Science Conference
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• 2011.11a
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• pp.551-556
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• 2011

This research presents an implementation strategy of Process Capability Index (PCI) according to the types of process characteristics. The types of process feature are classified as four perspectives of variation range, time period, error position, and process stage. The paper examines short-term or long-term PCI, within or between variation, position of precision or accuracy, and inclusion of measurement or calibration stage. Moreover, the study proposes normality test of unilateral PCI.

• Proceedings of the IEEK Conference
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• 2001.06e
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• pp.33-36
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• 2001

An automatic TCXO frequency-temperature test apparatus was firstly developed by using thermoelectric device may. The developed system swing stably the test temperature range from -40$^{\circ}C$ to +80$^{\circ}C$ for about 1 hour The rising temperature ratio was fairly linear with time in this test temperature range. The temperature could be controlled error in error range of ${\pm}$0.05$^{\circ}C$ in this system. The frequency-Temperature properties of TCXO or the thermoelectric properties of other electric device.

• Geomechanics and Engineering
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• v.13 no.4
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• pp.685-699
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• 2017

In order to determine the rate of penetrability, water pressure test is used before the grouting. One of the parameters which have the highest effect is pressure. Mathematical modeling is used for the first time in this study to determine the optimum pressure. Thus, the joints that exist in the rock mass are simulated using cylindrical shell model. The joint surroundings are also modeled through Pasternak environment. In order to validate the modeling, pressure values obtained by the model were used in the sites of Seymareh and Aghbolagh dams and the relative error rates were measured considering the differences between calculated and actual pressures recorded in these operations. In water pressure test, in Seymareh dam, the error values were equal to 4.75, 3.93, 4.8 percent and in the Aghbolagh dam, were 22.43, 5.22, 2.6 percent and in grouting operation in Seymareh dam were equal to 9.09, 32.50, 21.98, 5.57, 29.61 percent and in the Aghbolagh dam were 2.96, 5.40, 4.32 percent. Due to differences in rheological properties of water and grout and based on the overall results, modeling in water pressure test is more accurate than grouting and this error in water pressure test is 7.28 percent and in grouting is 13.92 percent.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.7
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• pp.1223-1228
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• 2008

While a high frequency source is used for measuring the ground impedance, there are several factors having an effect on the measured value. A primary factor of the measurement error is the ac mutual coupling between current and potential test leads. The mutual coupling causes the test current to induce a voltage into the potential test lead that adds to the actual ground potential rise and produces a significant measurement error as the length of the test leads paralleled is prolonged. In order to avoid the mutual coupling, it is recommended that the ground impedance be measured by angled arrangement of test leads. The mutual impedance due to the inductive coupling with an angle of $90^{\circ}$ was calculated at $0^{\circ}$ by Campbell/Foster Method. With an angle of $180^{\circ}$, the mutual impedance was calculated large value enough to introduce a fairly large margin of error, however, the measured value of ground impedance was close to the value at $90^{\circ}$.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.8
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• pp.347-353
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• 2002

This paper presents an accurate method for measuring the ground resistance in powered grounding system. Most of substations and electric power equipments are interconnected to an extensive grounding network of overhead ground wires, neutral conductors of transmission lines, cable shields, and etc. The parasitic effects due to circulating ground currents and ground potential rise make a significant error in measuring the ground resistance. The test current transition method was proposed to reduce the effects of stray ground currents, ground potential rise and harmonic components in measurements of the ground resistance for powered grounding systems. The instrumental error of the test current transition method is decreased as the ratio of the test current signal to noise(S/N) increases. It was found from the test results that the proposed measuring method of the ground resistance is more accurate than the conventional fall-of-potential method or low-pass filter method, and the measuring error was less than 3[%]when S/N is 10.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2020.11a
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• pp.241-243
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• 2020

The high computational complexity of deep learning algorithms has led to the development of specialized hardware architectures. However, soft errors (bit flip) may occur in these hardware systems due to voltage variation and high energy particles. Many error correction methods have been proposed to counter this problem. In this work, we analyze an error correction mechanism based on repetition codes and an activation function. We test this method by injecting errors into weight filters and define an ideal error rate range in which the proposed method complements the accuracy of the model in the presence of error.

• Journal of Elementary Mathematics Education in Korea
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• v.14 no.3
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• pp.885-905
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• 2010

This study questions that mathematical evaluations strive to memorize fragmentary knowledge and have an objective test. To solve these problems on mathematical education We did descriptive test. Through the descriptive test, students think and express their ideas freely using mathematical terms. We want to know if that procedure is correct or not, and, if they understand what was being presented. We studied this because We want to analyze where and what kinds of faults they committed, and be able to correct an error so as to establish a correct mathematical concept. The result from this study can be summarized as the following; First, the mistakes students make when solving the descriptive tests can be divided into six things: error of question understanding, error of concept principle, error of data using, error of solving procedure, error of recording procedure, and solving procedure omissions. Second, students had difficulty with the part of the descriptive test that used logical thinking defined by mathematical terms. Third, errors pattern varied as did students' ability level. For high level students, there were a lot of cases of the solving procedure being correct, but simple calculations were not correct. There were also some mistakes due to some students' lack of concept understanding. For middle level students, they couldn't understand questions well, and they analyzed questions arbitrarily. They also have a tendency to solve questions using a wrong strategy with data that only they can understand. Low level students generally had difficulty understanding questions. Even when they understood questions, they couldn't derive the answers because they have a shortage of related knowledge as well as low enthusiasm on the subject.

• Journal of the Korea Society of Computer and Information
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• v.13 no.2
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• pp.19-29
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• 2008

In case of unit testing, White-box test can be used to closely check source code and to analyze logic and statement errors. On the other hand, in case of function testing of system level, Black-box test can be mainly used to compare actual and expected results by inputting test data because the scale of function is large. This Black-Box test in system testing level has problem in tracing errors in source code when we find errors. Moreover applying White-box test is not easy for system testing level because the levels of test target are different. Therefore this paper suggests the vertical test method of a practical and integrated system level which can checks up to source code level using White-box test style although it aims to test the highly abstract level like a system function. In addition, the experiment explains how to apply the vertical test by displaying an example which traces from UML specification model to the source code and also shows efficiency of error trace.