• Proceedings of the KSR Conference
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• 2004.10a
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• pp.1413-1418
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• 2004

This paper shows the analysis of the inductive power transfer system in conjunction with series resonant converter operating variable high frequency. Of particular interest is the sensitivity of the complete system to variations in operational frequency and parameters. In inductive power transfer system, electrical power is transferred from a primary winding in the form of a coil or track, to one or more isolated pick-up coils that may relative to the primary. The ability to transmit power without contact enables high reliability and easy maintenance that allows inductive power transfer system to be implemented in hostile environments. This technology has found application in many fields such as electric vehicles, PRT(Personal Rapid Transit) etc. The coupling between the primary and secondary is then presented to include the effects of parameter and operational frequency variation.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.1
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• pp.1-6
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• 2009

Air core based transformers have been designed, simulated and fabricated by using micromachining process for the application of wireless power transmission with the range of frequency from 1 GHz to 20 GHz. Fabricated transformers are the types of solenoid transformers with primary and secondary coils. the size of fabricated transformer is $1.1{\times}1.5{\sim}2.15\;mm$ including ground shield. Transformers have been measured by dividing two groups based on the turns ratio between primary coil and secondary coil which are 1:1 transformers(the number of turns of primary coil and secondary coil: 3/3, 5/5, 7/7) and l:n transformers(the number of turns of primary coil and secondary coil: 3/3, 3/6, 3/9). As a result of the measurement, the lowest insertion loss of transformers ranged from 2 dB to 2.8 dB according to the number of turns between primary coil and secondary coil. And the lowest insertion loss from the transformers was measured at the frequency from 7 GHz to 11 GHz according to the number of turns between primary coil and secondary coil. Based on the measurement data from the microfabricated transformers, the transformer with the 3/3 turns in the primary coil and secondary coil showed best performance compared to others in terms of lowest insertion loss, lowest insertion loss frequency and bandwidth.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.21
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• pp.9335-9339
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• 2014

Background: To determine the frequency of primary circulating prostate cells (CPC) detection according to age and serum PSA levels in a cohort of men undergoing screening for prostate cancer and to determine the diagnostic yield in those men complying with the criteria for prostate biopsy. Materials and Methods: A prospective study was carried out to analyze all men evaluated in a hospital prostate cancer screening program. Primary CPCs were obtained by differential gel centrifugation and detected using standard immunocytochemistry using anti-PSA, positive samples undergoing a second process with anti-P504S. A malignant primary CPC was defined as PSA+ P504S+, and a test positive if 1 cell/4ml was detected. The frequency of primary CPC detection was compared with age and serum PSA levels. Men with a PSA >4.0ng/ml and/or abnormal rectal examination underwent 12 core prostate biopsy, and the results were registered as cancer/no-cancer and compared with the presence/absence of primary CPCs to calculate the diagnostic yield. Results: A total of 1,117 men participated; there was an association of primary CPC detection with increasing age and increasing serum PSA. Some 559 men underwent initial prostate biopsy of whom 207/559 (37.0%) were positive for primary CPCs and 183/559 (32.0%) had prostate cancer detected. The diagnostic yield of primary CPCs had a sensitivity of 88.5%, a specificity of 88.0%, and positive and negative predictive values of 78.3% and 94.9%, respectively. Conclusions: The use of primary CPCs for testing is recommended, since its high negative predictive value could be used to avoid prostate biopsy in men with an elevated PSA and/or abnormal DRE. Men positive for primary CPCs should undergo prostate biopsy. It is a test that could be implemented in the routine immunocytochemical laboratory.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6615-6619
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• 2015

Background: The expression of HER-2 in prostate cancer has been linked to disease progression. We analysed the presence of HER-2 expression in primary tumors in men undergoing radical prostatectomy, its association with clinical and pathological findings, and its expression in secondary circulating prostate cells (CPCs) during follow up, as well as links with biochemical failure and the effects of androgen blockade. Materials and Methods: Consecutive men undergoing radical prostatectomy for histologically confirmed prostate cancer were analyzed. HER-2 expression in the primary tumor was assessed using the HercepTest(R), CPCs were identified from blood samples using standard immunocytochemistry with anti-PSA and positive samples with the HercepTest(R) to determine HER-2 expression. The influence of HER-2 expression on the frequency of biochemical failure and effects of androgen blockade was determined. Results: 144 men with a mean age of $64.8{\pm}10.3$ years participated, with a median follow up of 8.2 years. HER-2 was expressed in 20.8% of primary tumors; it was associated with vascular infiltration and older age, but not with other clinical pathological findings. Some 40.3% of men had secondary CPCs detected, of which 38% expressed HER-2. Men CPC (+) had a higher frequency of biochemical failure, but there was no difference in HER-2 expression of CPCs with the frequency of biochemical failure. After androgen blockade, men with HER-2 (+) positive secondary CPCs had a higher frequency of disease progression to castrate resistant disease. Conclusions: HER-2 plays a dual role in the progression of prostate cancer; firstly it may increase the potential of tumor cells to disseminate from the primary tumor via the blood by increasing vascular infiltration. In the presence of androgens, there is no survival advantage of expressing HER-2, but once biochemical failure has occurred and androgen blockade started, HER-2 positive cells are resistant to treatment, survive and grow leading to castration resistant disease.

• Journal of Electrical Engineering and Technology
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• v.3 no.4
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• pp.528-537
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• 2008

Primary frequency control(PFC) has the ability to regulate short period random variations of frequency during normal operation conditions and also to respond rapidly to emergencies. However, during the past decade, numerous significant sized blackouts occurred worldwide that resulted in serious economic losses. Therefore, the conclusion has been reached that the ability of the current PFC to meet an emergency is poor, and security of power systems should be improved. An alternative to enhance the PFC and thus security is to store excessive amounts of energy during off-peak load periods in efficient energy storage systems for substituting the primary control reserve. In this sense, superconducting magnetic energy storage(SMES) in combination with a static synchronous compensator(STATCOM) is capable of supplying power systems with both active and reactive powers simultaneously and very rapidly, and thus is able to enhance the security dramatically. In this paper, a new concept of PFC based on incorporating a STATCOM-SMES is presented. A complete detailed model is proposed and a new control scheme is designed, comprising an enhanced frequency control scheme, and a fully decoupled current control strategy in d-q coordinates with a novel controller to prevent dc bus capacitors voltage drift/imbalance. The performance of the proposed control schemes is validated through digital simulation carried out using MATLAB/Simulink.

• Journal of Electrochemical Science and Technology
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• v.1 no.1
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• pp.39-44
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• 2010

1.5 V and 3.0 V-class film-type primary batteries were designed for radio frequency identification (RFID) tag. Efficient fabrication processes such as screen-printings of conducting layer ($25{\mu}m$), active material layer ($40{\mu}m$ for anode and $80{\mu}m$ for cathode), and electrolyte/separator/electrolyte layer ($100{\mu}m$), were adopted to give better performances of the 1.5 V-class film-type Leclanch$\acute{e}$ primary battery for battery-assisted passive (BAP) RFID tag. Lithium (Li) metal is used as an anode material in a 3.0 V-class film-type $MnO_2||$Li primary battery to increase the operating voltage and discharge capacity for application to active sensor tags of a radio frequency identification system. The fabricated 3.0 V-class film-type Li primary battery passes several safety tests and achieves a discharge capacity of more than 9 mAh $cm^{-2}$.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38B no.10
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• pp.843-850
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• 2013

Cognitive radio systems have been considered as a strong solution of frequency scarcity due to the limit of frequency resources. This paper proposed an active interference management scheme that the secondary system can coexist with the primary system in the same frequency band without interference. Using the proposed protocol, the secondary user acquires interference channel information and transmit/receive filter information and designs precoding matrix using these information. Since interference from the secondary systems are collected to unused subchannels of the primary system, the primary system can suppress interference without additional process. The secondary systems suppress interference from the primary system using whitening matched filter so that the spectral efficiency can be improved. Numerical results provides that the proposed scheme improves performance of the secondary systems without interference to the primary system and do not degrade performance of the primary system even if the number of the secondary systems increases.

• The Journal of Korean Obstetrics and Gynecology
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• v.35 no.3
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• pp.122-136
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• 2022

Objectives: The aim of this study is to investigate Heart Rate Variability (HRV) characteristics of patients with primary dysmenorrhea at the menstrual phase. Methods: 7 databases (Pubmed, Cochrane library, CNKI, RISS, KISS, OASIS, ScienceON) were searched for eligible studies published before 2021 December. The studies comparing HRV between patients with primary dysmenorrhea and controls were included. A random-effects model was used to evaluate differences of HRV parameters between patients with primary dysmenorrhea and controls. Results: 4 articles were included in this review based on inclusion and exclusion criteria. SDNN (Standard deviation of NN intervals), RMSSD (Square root of the mean squared difference of successive NN intervals), mean PR (Mean of pulse rate), LF (Low frequency), HF (High frequency), was the most frequently used as HRV parameters. RMSSD was significantly lower in patients with primary dysmenorrhea than controls. There was no statistically significant difference of other HRV parameters between patients with primary dysmenorrhea and controls. Conclusions: This study suggests that parasympathetic activity and overall functions of autonomic nervous system might be decreased in patients with primary dysmenorrhea at the menstrual phase. In the future, well-designed clinical studies using HRV and additional meta-analysis should be conducted to obtain a wealth of information about HRV characteristics of patients with primary dysmenorrhea.

• Journal of Korea Foundry Society
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• v.29 no.2
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• pp.78-85
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• 2009

Functionally graded microstructure of centrifugal cast Al-Si alloy, especially distribution of primary Si particles according to the changes of melt pouring temperature and rotation frequency was investigated by numerical simulation. Moving velocity of Si particles increased as the melt pouring temperature and rotational frequency of mold increased. Therefore, segregation tendency of primary Si particles toward inner side of cylindrical sample increased as the melt pouring temperature and rotational frequency of mold increased. Rich distribution region of particles was located at 0.9, 0.7, 0.4 mm from inner surface of cylindrical sample under the centrifugal cast condition of $750^{\circ}C$ melt pouring temperature and 1500, 2000 and 2500 rpm mold rotational frequencies, respectively, by numerical simulation.

• Journal of the Korea Institute of Military Science and Technology
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• v.2 no.2
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• pp.166-172
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• 1999

Weapon system is defined as a combination of primary system and logistics support system which are evaluated by capability and operational availability respectively. Weapon system developer thought that primary system was weapon system and also only primary system was important. Recent comparison of total life cycle cost showed that logistics support system was proved to be more important than primary system. However, until now no systematic approach to logistics support system development have applied in the area of developing support system and much money was exhausted by wrong logistics support system. We need to construct a universal metric for effectiveness of logistics support system and to cut out whatever activities or support elements which do not contribute to the metrics. This study describes a new approach under the name function approach to logistics support system development and also classifies five factors of failure frequency, stock out of frequency, administrative delay time, active repair time and logistic delay time that have influence on operational availability of logistics support system.