• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.5
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• pp.162-173
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• 1998

The high pressure common rail injection system offers a high potential for improving emmisions and performance characteristics in large direct diesel engines. High pressures in the common rail with electronic control allows the fuel quantity and injection timing to be optimized and controlled throughout a wide range of engine rpm and load conditions. In this study, high pressure supply pump, common rail, pipes, solenoid and control chamber, and nozzle were modeled in order to predict needle lift, rate of injection, and total injected fuel quantity. When the common rail pressure is raised up to 13.0 ㎫ and the targer injection duration is 1.0ms, the pressure drop in common rail is about 5.0㎫. The angle of effective pressurization is necessary to be optimized for the minimum pump drive torque and high pressure in common rail depending on the operating conditions. The characteristics of injection were also greatly influenced by the pressures in common rail, the areas of the inlet and exit orifice of the control chamber.

• Journal of Sensor Science and Technology
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• v.24 no.1
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• pp.35-40
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• 2015

Electrospinning method has easy preparation of nanofibers with a simple and versatile technique. Electrospun nanofiber is widely used by the simple approach and have great potentials in the numerous applicaitons of medicine, photonics, catalysts, sensors, etc. including advantage of their specific characteristics such as large surface to volume ratio. This paper focused on the fabrication of cobalt electrospun nanofibrer for applications such as electronic, optical and mechanical devices by metal based material. We fabricated cobalt nanofibers on aluminum foil by an electrospinning method. The electrospinning process was performed at a high voltage, 8 kV. The distance between the needle tip and the solution surface in the bath was 5 cm. The PVB - cobalt based nitrate solution was filled in a 10 mL syringe connected to a 22 gauge needle. We confirmed electrospun cobalt nanofiber after annealing process by SIMS (Secondary Ion Mass Spectrometry) analysis. The concept design, fabrication and results of mapping measurements are reported.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.22
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• pp.9865-9869
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• 2014

Background: Transthoracic fine needle aspiration (FNA) is one of several methods for establishing tissue diagnosis of lung lesions. Other tissue or cell sources for diagnosis include sputum, endobronchial biopsy, washing and brushing, endobronchial FNA, transthoracic core needle biopsy, biopsy from thoracoscopy or thoracotomy. The purpose of this study was to compare the sensitivity and specificity of FNA and other diagnostic tests in diagnosing lung lesions. Materials and Methods: The population included all patients undergoing FNA for lung lesions at Meir Medical Center from 2006 through 2010. Information regarding additional tissue tests was derived from the electronic archives of the Department of Pathology, patient records and files from the Department of Oncology. Sensitivity, specificity, diagnostic accuracy, and positive and negative predictive values were calculated for each test. Results: FNA was carried out in 245 patients. Malignant tumors were diagnosed in 190 cases (78%). They included adenocarcinoma (43%), squamous cell carcinoma (15%), non-small cell carcinoma, not otherwise specified (19%), neurondocrine tumors (7%), metastases (9%) and lymphoma (3%). The specificity of FNA for lung neoplasms was 100%; sensitivity and diagnostic accuracy were 87%. Conclusions: FNA is the most sensitive procedure for establishing tissue diagnoses of lung cancer. Combination with core needle biopsy increases the sensitivity. Factors related to the lesion (nature, degenerative changes, location) and to performance of all stages of test affect the ability to establish a diagnosis.

• Transactions on Electrical and Electronic Materials
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• v.13 no.5
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• pp.252-255
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• 2012

In order to characterize insulation properties of epoxy/micro-silica/nano-silicate composite (EMNC), long-term and short-term AC treeing tests were carried out undr non-uniform electric field generated between needle-plate electrodes. In a long-term test, a 10 kV (60 Hz) electrical field was applied to the specimen positioned between the electrodes with a distance of 2.7 mm in an insulating oil bath at $30^{\circ}C$, and a typical branch type electrical tree was observed in the neat epoxy resin and breakdown took place at 1,042 min after applying the 10 kVelectrical field. Meanwhile, the spherical tree with the tree length of $237{\mu}m$ was seen in EMNC-65-0.3 at 52,380 min (36.4 day) and then the test was stopped because the tree propagation rate was too low. In the short-term test, an electrial field was applied to a 3.5 mm-thick specimen at an increasing voltage rate of 0.5 kV/s until breakdown in insulating oil bath at $30^{\circ}C$ and $130^{\circ}C$, and the data was estimated by Weibull statistical analysis. The electrical insulation breakdown strength for neat epoxy resin was 1,763 kV/mm at $30^{\circ}C$, while that for EMNC-65-0.3 was 2,604 kV/mm, which was a modified value of 47%. As was expected, the breakdown strength decreased at higher test temperatures.

• Transactions on Electrical and Electronic Materials
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• v.14 no.6
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• pp.308-311
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• 2013

The effect of an electric field on the ac electrical treeing in various epoxy/reactive diluent systems was studied in a needle-plate electrode geometry. Diglycidyl ether of bisphenol A (DGEBA) type epoxy was used as a base resin, and 1,4-butanediol diglycidyl ether (BDGE) or polyglycol (PG) as a reactive diluent was introduced to the DGEBA system, in order to decrease the viscosity of the DGEBA epoxy system. BDGE was acted as a chain extender, and PG acted as a flexibilizer, after the curing reaction. To measure the treeing initiation time and the propagation rate, three constant alternating currents (ac) of 10, 13 and 15 kV/4.2 mm (60 Hz) were applied to the specimen, in a needle-plate electrode arrangement, at $30^{\circ}C$ of insulating oil bath. When 10 kV/4.2 mm (60 Hz) was applied, the treeing initiation time and the propagation rate in the DGEBA system were 356 min and $1.10{\times}10^{-3}$ mm/min, respectively, those in the DGEBA/BDGE system were 150 min and $1.14{\times}10^{-3}$ mm/min, respectively. Those in the DGEBA/PG system were 469 min and $1.05{\times}10^{-3}$ mm/min, respectively. As 15 kV/4.2 mm (60 Hz) was applied, the propagation rate in the DGEBA system was $5.41{\times}10^{-3}$ mm/min, and that in the DGEBA/PG system was $1.42{\times}10^{-3}$ mm/min. These values meant that PG could be used as a reactive diluent in the DGEBA system, without the deterioration of the insulation breakdown property.

• Transactions on Electrical and Electronic Materials
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• v.13 no.2
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• pp.85-88
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• 2012

Studies on the effects of layered silicate content on the AC electrical treeing and breakdown behaviors of epoxy/layered silicate nanocomposites were carried out in needle-plate electrode geometry. Wide-angle X-ray diffraction (WAXD) analysis and transmission electron microscopy (TEM) observation showed that 1 wt% of the multilayered silicate was fully exfoliated into nano-sized monolayers in the epoxy matrix however, over 3 wt% of the silicate was in an intercalated state. When 1 wt% layered silicates were incorporated, an electrical tree was initiated in 439 min and propagated at a speed of 2.3 ${\mu}m$/min after applying 781.4 kV/mm, representing a decreased in starting initiation time by a factor of 11.0 and increase in propagation speed by a factor 8.2 in comparison with neat epoxy resin. These values were in great decline after the layered silicate content was increased to 3wt% which implies that the exfoliated silicate blocked the tree initiation and propagation processes effectively. However the effect was largely decreased in the intercalated state.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2028-2030
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• 1999

In this paper, partial discharge(PD) was generated under the two types of needle -plane electrodes in the air. Using a monopole antenna to detect the radiated electromagnetic waves by stream of charge between the electrodes. the progress of partial discharge was studied. To analyze the progress of PD, statistical re-search was introduced. It was executed by personal computer and it can be possible to visualize the progress of PD. The t-test was used for lower voltage applied. The population of background noise spectrum and applied voltage spectrum showed the difference. The new method was introduced to analyze the spectrum. According tho the magnitude of applied voltage, the different statistical methods were used. The results obtained from this work will provide the useful information on partial discharge in time to come.

• Korean Journal of Acupuncture
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• v.22 no.4
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• pp.9-27
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• 2005

Objective : hypothesis. First of all, there exists electric property in meridian and meridian point. Second of all, energy flowing in meridian is related with electric property. Third of all, there is electronic interaction between the operator who performs acupuncture therapy and the receiver who is given acupuncture therapy. Forth of all, acupuncture effects may depend on the electric capacity which is transferred between the operator and the receiver via acupuncture needle. Methods : Under the hypothesis, I studied the effects of electric charge in ST37(+) and ST39(-) generated by Apchim (押鍼) manipulation which was stimulated at ST36 point. And compared with data on the changes of electric charge from the hand of the operator during acupuncture stimulation. Electric charge induced via acupuncture needle from the operator may be important factor that causes the changes of electric charge in meridian and acupoint in the receiver. Therefore we investigated the changes of electric charge induced by the operator using Maclab 400 by the following methods. The one was in stable electric circle condition and the other was in unstable electric circle condition. In this experiments, the changes of electric charge from the stimulation type of Apchim manipulation performed in our lab condition in acupuncture therapy was induced at least three factor, one was the difference of bio-potentials between the operator and the receiver of acupuncture therapy, another was the depth of acupuncture insertion from the skin of the receiver the other was an electromyogram of the receiver. Results :The data imply that the first factor should make a capacitance current when the operator touched the acupuncture needle which was inserted in the receiver. Therefore, the results suggest that capacitance currents stimulus in electronic view may be important factor in acupuncture therapy between the operator and the receiver of acupuncture therapy.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.3
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• pp.93-100
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• 2018

The electronic acupuncture has the advantage of treating the patient with acupuncture by simultaneously analyzing the patient's physical condition and treatment condition. In this paper, it is proposed and developed an electronic acupuncture algorithm embedded in a multi pad. Especially, it is implemented the control algorithm using the optimal electronic dipstick calculation, sensing pad and DSP system for the patient's body condition. Moreover, in this paper, it is developed SW and HW prototypes that can receive personal information by patient and can receive multi-array type electronc needle guiding procedure based on WEB.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.24 no.5
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• pp.111-116
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• 2024

These days, the number of patients committing suicide due to depression and stress is rapidly increasing. In addition, if stress and depression persist for a long time, it can cause heart disease, brain disease, and high blood pressure. Arteriosclerosis, known as the main cause of cerebrovascular disease, is a dangerous disease in which cholesterol accumulates in blood vessels, narrowing them. However, no matter how much modern medicine has developed, stroke patients are in a very difficult situation with no special medicine or treatment. In this paper, to solve these problems, we proposed a smart electronic acupuncture device that treats patients' diseases based on electronic acupuncture. In addition, an algorithm for predicting the risk of health status of stroke patients and a posture recognition algorithm were proposed and a computer simulation experiment was performed.