• Current Optics and Photonics
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• 제1권5호
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• pp.538-543
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• 2017

Progressive addition lenses (PAL) have very wide application in the modern glasses market. The unique progressive surface can make a lens have progressive refractive power, which can meet the human eye's different needs for distance-vision and near-vision. According to the national glasses fabrication standard, the difference between actual optical power after fabrication and nominal design value should be less than 0.1D over the lens effective area. The optical power distribution of PAL is determined directly by the surface. Consequently, the surface processing accuracy requirement is proposed. Beginning from the surface expressions of progressive addition lenses, the relationship equations between the surface sag and optical power distribution are derived. They are demonstrated through tolerance analysis and test of an example progressive addition lens with addition of 2.09D (5.46D-7.55D). The example addition surface is fabricated under given accuracy by a single-point diamond ultra-precision machine. The optical power of the PAL example is tested with a focal-meter after fabrication. The optical power addition difference between test result and design nominal value is 0.09D, which is less than 0.1D. The derived relationship between the surface error and optical power is verified from the PAL example simulation and test result. It can provide theoretical tolerance analysis proof for the PAL surface fabricating process.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.731-732
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• 2007

This paper presents the final configuration of test field and test items for the application of IEC 60364-4-44 in Korea. IEC 60364-4-44 provides rules for the protection against the effects of conducted and radiated disturbances on electrical installations. Especially this standard deals with the protection of low voltage facility against the ground fault in the high voltage side of power distribution system. Many countries define the regulations on the use of electrical facilities based on their own power system and technical references which are considered to be suitable for them. The background of circuit of IEC 60364-4-44 is based on the ungrounded system as most of European countries. However, domestic electric power distribution system is based on multi-grounding system different from European system. Therefore, it is necessary to evaluate or prove the effect of the IEC 60364-4-44 for introducing and applying it to the domestic grounding system as a national standard. The authors with KEA(Korea Electric Association) carried out a project on the application of IEC 60364-4-44 to Korean electrical installations of buildings sponsored by Korean ministry of commerce, industry and energy for three years(2004.4.1$\sim$2007.3.31). The test field is established in K.E.R.I.(Korea Electrotechnology Research Institute), which is the purpose of evaluating the formula to calculate touch voltage and stress voltage in the IEC standards. This paper presents some considerations and final configuration of test field to evaluate and introduce the IEC 60364-4-44 applicable to domestic rule for the protection against ground fault.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.616-618
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• 2007

This paper describes the mechanical and electrical test on HVDC submarine cable, Flexible Repair Joint and termination for 180kV. This HVDC submarine cable was manufactured using LS cable's unique skill and would be applied the HVDC submarine cable system in korea. The performance test consist of mechanical test and electrical test. The tensile bending test and tensile test was done as the mechanical test and Electrical test is DC voltage and Impulse test. The tensile bending test carried out 6 times(double of specified times) for maximum reliability. The DC test voltage is $\pm$400kV/1hr. We estimate the lower limit of DC breakdown voltage is 600kV. The impulse test voltage is $\pm$800kV/10shots. The type of developed cables is the MI type. Its insulation consist of paper tapes impregnated with a high viscosity oil. The development of new HVDC cable is available for HVDC underground or submarine power transmission. The developed HVDC cable, FRJ and termination have passed the mechanical and electrical test successfully and showed excellent performance.

• Journal of Power Electronics
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• 제8권3호
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• pp.217-227
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• 2008

The electric power subsystems (EPS) of most remote sensing satellites consist of a solar array as a source of energy, a storage battery, a power management and control (PMC) unit and a charge equalization unit (CEU) for the storage battery. The PMC and CEU use high frequency transformers in their power modules. This paper presents a design, implementation and testing results of a high frequency transformer for the EPS of satellite applications. Two approaches are used in the design process of the transformer based on the pre-determined transformer specifications. The transformer is designed based on an ETD 29 ferrite core. The implemented transformer consists of one center-tapped primary coil with eleven center-tapped secondary coils. The offline calculation results and measured values of R, L for transformer coils are convergence. A test circuit for measuring the transformer parameters like voltage, current and B-H hysteresis was implemented and applied. The test results confirm that the voltage waveforms of both primary and secondary coils were as desired. No overlapping occurred between the control signal and the transformer, which was not saturated during testing even during a short circuit test of the secondary channels. The dynamic B-H loop characteristics of the used transformer cores were measured. The sample test results are given in this paper.

• 한국콘텐츠학회논문지
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• 제5권1호
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• pp.229-236
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• 2005

System-On-a-Chip(SOC)을 테스트하는 동안에 요구되는 테스트 시간과 전력소모는 SOC내의 IP 코어의 개수가 증가함에 따라서 매우 중요하게 되었다. 본 논문에서는 수정된 스캔 래치 재배열을 사용하여 scan-in 전력소모와 테스트 데이터의 양을 줄일 수 있는 새로운 알고리즘을 제안한다. 스캔 벡터 내의 해밍거리를 최소화하도록 스캔 래치 재배열을 적용하였으며 스캔 래치 재배열을 하는 동안에 스캔 벡터 내에 존재하는 don't care 입력을 할당하여 저전력 및 테스트 데이터 압축을 하였으며 ISCAS 89 벤치마크 외호에 적용하여 모든 경우에 있어서 테스트 데이터를 압축하고 저전력 스캔 테스팅을 구현하였다.

• 기본간호학회지
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• 제10권1호
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• pp.68-77
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• 2003

Purpose: This study analyzed the effects of meridian massage on the muscle power, ROM, and ADL in persons with cerebral palsy. Method: A non-equivalent pre-test/post-test design was used. The data were collected from August to October, 2000 from 10 persons with cerebral palsy (a control group of 5 and an experimental group of 5). Muscle power was evaluated with the Brunnstrom-Dennen gravity test, ROM with a goniometer, and ADL with a self developed ADL scale. T-test, repeated measure ANOVA were used for statistical analysis. Result: The results are; 1. For muscle power, both time series group difference (F=10.66, p=0.000) and the total period group difference (F=72.67, p=0.000) were significant between the two groups. 2. ROM was not significantly different between the two groups. 3. For ADL, both time series group difference (F=7.09, p=0.001) and total period group difference (F=35.99, p=0.000) were significant between the two groups. Conclusion: Overall, this study shows that Meridian massage is effective for muscle power, ROM, and ADL in persons with cerebral palsy person. So it can be used to develope effective nursing programs to improve the function of motion of persons with cerebral palsy.

• 전자공학회논문지 IE
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• 제45권3호
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• pp.5-12
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• 2008

디지털 논리회로의 테스트 데이터와 전력소비를 단축시킬 수 있는 효율적인 테스트 방법을 제안한다. 제안 하는 테스트 방법은 테스트장비내의 테스트 데이터 저장 공간을 줄이는 하이브리드 run-length 인코딩 벙법에 기초하고, 수정된 Bus-invert 코딩 방법과 스캔 셀 설계를 제안하여, 스캔 동작시의 개선된 전력 단축효과를 가져온다. ISCAS'89 벤치마크 회로의 실험결과 고장 검출율의 저하 없이 평균 전력은 96.7%, 피크전력은 84%의 단축을 보이며 테스트 데이터는 기존 방법보다 78.2%의 압축을 갖는다.

• Journal of information and communication convergence engineering
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• 제11권1호
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• pp.56-61
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• 2013

Modern integrated circuits (ICs) are becoming an integrated parts of analog, digital, and radio frequency (RF) circuits. Testing these RF circuits on a chip is an important task, not only for fabrication quality control but also for tuning RF circuit elements to fit multi-standard wireless systems. In this paper, RF test circuits suitable for embedded testing are introduced: RF power detectors, power control circuits, directional couplers, and six-port reflectometers. Various types of embedded RF power detectors are reviewed. The conventional approach and our approach for the RF power control circuits are compared. Also, embedded tunable active directional couplers are presented. Then, six-port reflectometers for embedded RF testing are introduced including a 77-GHz six-port reflectometer circuit in a 130 nm process. This circuit demonstrates successful calibrated reflection coefficient simulation results for 37 well distributed samples in a Smith chart. The details including the theory, calibration, circuit design techniques, and simulations of the 77-GHz six-port reflectometer are presented in this paper.

• Nuclear Engineering and Technology
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• 제51권2호
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• pp.561-572
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• 2019

In the design criterion for the nuclear power plant piping system, the limit state of the piping against an earthquake is assumed to be plastic collapse. The failure of a common piping system, however, means the leakage caused by the cracks. Therefore, for the seismic fragility analysis of a nuclear power plant, a method capable of quantitatively expressing the failure of an actual piping system is required. In this study, it was conducted to propose a quantitative failure criterion for piping system, which is required for the seismic fragility analysis of nuclear power plants against critical accidents. The in-plane cyclic loading test was conducted to propose a quantitative failure criterion for steel pipe elbows in the nuclear power plant piping system. Nonlinear analysis was conducted using a finite element model, and the results were compared with the test results to verify the effectiveness of the finite element model. The collapse load point derived from the experiment and analysis results and the damage index based on the stress-strain relationship were defined as failure criteria, and seismic fragility analysis was conducted for the piping system of the BNL (Brookhaven National Laboratory) - NRC (Nuclear Regulatory Commission) benchmark model.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.940-947
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• 2011

Load capacity varies according to a day of the week in traction power supply system, because time schedule in railway is changed as demand for passengers and freights. Therefore, Voltage drop also varies as load capacity. In Korea railway, Voltage collected from catenary in train is decreased, as load supplied traction power supply system is increased. Therefore, investigation about voltage drop should be performed, before development of countermeasure against voltage drop. The investigation can be performed by simulation or field test. Naturally, field test is more precise than simulation. In addition, field test should be carried out at peak load. This paper presents test and analysis about voltage drop in railway. The test is performed in both a day of the week and weekend. The analysis is figured out comparison load capacity between two days and voltage drop across terminal.