• 전자공학회논문지B
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• 제33B권12호
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• pp.113-121
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• 1996

This paper presents a 37.5kVA (125kVp, 300mA) high frequency inverter type power supply for diagonostic X-ray generator with two HFHV (high-frequency high-voltage) isolating transformers. The output regulations, X-ray tuve voltage and tube current, are obtained by two high frequency inverters with the each other feedback PI controller and operating time switch for selecting shooting time and synchronizing two inverters. The operating modes and design consideration of the proposed power supply are given. Issues in the design of two HFHV isolating transformersfors high volage genrating and filament heating are discussed. Experimental results are presented to verify the performance of the designed power supply for varying load conditions. The proposed apparatus has several advnatages, e.g., the fast rising time of tube voltae, accuracy and reduced component size etc.

• 대한기계학회논문집A
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• 제26권12호
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• pp.2662-2669
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• 2002

Recently structural applications of adhesive bonding method have been increased extensively in automobile industry. Adhesively-bonded joints which are used in automobile field are exposed to various environmental conditions. In this study, several environmental factors were concerned to evaluate their effects on the adhesive strength such as air temperature, water temperature, exposed time in water. The specimens are exposed for 1, 10 and 100 hours at various air temperatures to evaluate the effects of the air and water temperature on the adhesive strength. It is proved that the adhesive strength decrease with rising the air and water temperature, and the adhesive strength decrease steeply at the higher temperature with increasing the exposure time in water.

• 대한전자공학회논문지TE
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• 제37권3호
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• pp.60-65
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• 2000

산업공정제어에 지속적으로 널리 사용되는 PID제어기의 최적이득 자동 동조에 관한 새로운 방법을 제안한다. 이 방법은 먼저 제어대상의 계단응답으로부터 모델링된 1차 지연계를 Fade 근사화하고, Ziegler-Nichols의 방법으로 초기값을 정한 후, 최대 오버슈트, 감쇠비, 상승시간, 정정시간을 포함하는 퍼지추론함수를 최대로 하는 PID계수를 구함으로써 제어대상의 특성이나 부동작시간의 변화에도 적응성이 좋다는 장점이 있다

• 한국기계가공학회지
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• 제11권4호
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• pp.1-6
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• 2012

This paper addresses the issue of Renewable Energy for Electricity Storage device is one of the NAS (Sodium-Sulfur) battery will be about the module. For safety reasons, not the actual battery cells using a dummy cell in the module's operating temperature setting to examine the characteristics of the insulation vacuum of the wall temperature and external temperature changes measured over time. Upper and lower boundaries of the wall vacuum insulation characteristics cotton C intervals over time, average $5^{\circ}C$, but the temperature is rising, 4C section with little temperature change did not occur. On the other hand, about $3^{\circ}C$ in section 4D, and it was confirmed that the temperature rises. Wall vacuum insulation characteristics over time to look at the experiments and measurements are described.

• 한국소음진동공학회논문집
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• 제16권4호
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• pp.380-386
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• 2006

ATM is a machine that receives and pays money. The gate module of ATM separates forgeries from bills and changes the transfer direction of bills. In this paper, the dynamic behavior of the gate was analyzed numerically and experimentally. The moment of inertia of the gate lever, the driving force of the solenoid and the spring force were measured, respectively. And the displacements of the plunger, the Input voltage and current were measured experimentally. The measured dynamic behaviors were simulated numerically using Maxwell program which can accommodate the electromagnetic problem of the solenoid. Through the analysis, the design factors were found to make a fast and reliable new ATM gate module.

• 한국측량학회지
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• 제32권6호
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• pp.617-623
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• 2014

The rapid urbanization in developing countries has caused trasportation problems that need to be solved. For that reason, the study evaluates the potential of cycling in the densely populated part of Kathmandu valley. Slopes and existing roads have been applied as the input cost rasters for finding the shortest cost routes between stations. By taking the average cycling velocity, time to travel from station to destination were compared with the average commuting time in the public transportation. The result comes out as similar time with the public transportation. Although the cycling seems potential replacement for public transportation commuters, in fact, there are some setbacks needed to be supported by the government to make it reality in future.

• KIEE International Transactions on Electrophysics and Applications
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• 제3C권5호
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• pp.177-181
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• 2003

Partial discharge pulse shapes from variable PD (partial discharge) sources sustain many characteristics such as types of PD. Ultra high frequency antennas have wide bandwidth from 30KHz to 2㎓. Therefore, signals taken from a UHF antenna have important attributes (rising time, falling time, shape factor, etc.) for electromagnetic sources, such as PD sources. We investigated PD pulse shapes from several PD sources using a UHF antenna and the results were used for classification of PD sources. Features for discrimination are extracted from frequency distribution and LPC (Linear Prediction Coefficient) of time signal. RBFN are used for investigating the possibility of classification of multi-PD sources.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 E
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• pp.1779-1781
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• 1998

We are going to design the Square Pulse Generator use of PCPS (Photo-Conductive Power Switch) for Blumlein lain. The circeuit is made of LC device and it is simulated by Schematics Evaluation Version 8.0 of MicroSim. After charged by DC voltage 15[kV]. When the switch is ON, Square pulse is generated after pause time 1.7857[${\mu}s$]. The square pulse is maximum peak voltage 13.987[kV], pulsed width 3.4017[${\mu}s$], rising time 0.7474[${\mu}s$], falling time 1.1718[${\mu}s$].

• 한국분무공학회지
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• 제15권4호
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• pp.163-169
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• 2010

Jetting stability is the most important factors in inkjet printing because printing quality is totally determined by shape of the droplets on the substrate. In order to acquire stable jet, viscosity and dynamic behavior of the ink must be considered. In addition, waveform to drive the inkjet printhead is also to be controlled. In this study, the driving waveform composed of rising time, dwell time and falling time is optimized to obtain a stable jetting using drop watcher system. Also, effect of ink viscosity on jetting is experimentally investigated by changing the temperature of ink cartridge. As a result, jetted drop having uniform velocity is acquired.

• 한국조명전기설비학회지:조명전기설비
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• 제13권2호
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• pp.195-195
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• 1999

This paper is Proposed a new method to deal with the optimized auto-tuning for the PID controller which is used to the process-control in various fields. First of all, in this method, 1st order delay system with dead time which is modelled from the unit step response of the system is Pade-approximated, then initial values are determined by the Ziegler-Nickels method. So we can find the parameters of PID controller so as to minimize the fuzzy criterion function which includes the maximum overshoot, damping ratio, rising time and settling time. Finally, after studying the parameters of PID controller by Backpropagation of Neural-Network, when we give new K, L, T values to Neural-Network, the optimized parameter of PID controller is found by Neural-Network Program.