• 제목/요약/키워드: U-Profile

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이중 U-슬롯을 이용한 광대역 마이크로스트립 안테나 (Wideband Microstrip Antenna with the Double U-slots)

  • 오은실;윤영중
    • 한국통신학회논문지
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    • 제27권7B호
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    • pp.727-736
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    • 2002
  • 본 논문에서는 단일 안테나 소자만을 이용하여 PCS (하향 링크: 1.75GHz~1.78GHz, 상향 링크: 1.84GHz~1.87GHz) 및 IMT-2000 (하향 링크: 1.92GHz~l.98GHz, 상향 링크 2.11GHz~2.17GHz) 서비스 대역을 동시에 만족하는 광대역 마이크로스트립 안테나를 제안한다. 큰 전류의 세기를 유도하는 U-슬롯 안쪽에 최적화된 다른 U-슬롯$_2$를 삽입하고, 이것이 안테나 성능에 미치는 영향에 대해 알아보았다. 결국 U-슬롯$_2$에 의해 또 다른 공진을 유도함으로써 넓은 광대역 특성을 얻었고, 급전구조에 정합 스터브를 삽입하여 좀 더 넓은 대역을 확보함으로써 두 서비스 대역을 만족하도록 설계하였다. 제작된 이중 U-슬롯 마이크로스트립 안테나는 VSWR<2를 기준으로 1.67GHz~2.27GHz (600MHz)의 30.45%로 두 서비스를 모두 만족하는 광대역 임피던스 대역폭을 얻을 수 있었다.

UPFC 운용에 의한 전력 시스템 최적 전압 유지 (Maintaining Optimal Voltage Profile by the Operation of UPFC)

  • 김태현;문채주;박종근;문승일;서장철;한병문
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 하계학술대회 논문집 A
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    • pp.265-267
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    • 2000
  • A method to compute the reactive powers of the added buses by the decoupled UPFC model for the optimal voltage profile is presented, by which the voltage magnitudes of PQ buses can get closer to the reference value(usually one p.u.). The performance index for assessing how much the voltage magnitude is closer to the reference value is defined as the squared sum of the present voltage minus the reference voltage multiplied by the weighting number associated with the relative importance of the buses. Numerical example in a 10-unit 39-bus power system with 2 UPFC's shows that the performance index can be very much reduced by operating multi UPFC's with the reactive powers for the optimal voltage profile proposed in this paper.

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불교란 토양시료의 불포화대 수리전도도-유효공극율의 상판관계 분석

  • 이병선;이기철;우명하;이주영;김정희;우남칠
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
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    • pp.411-414
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    • 2006
  • This study was examined to determine hydraulic conductivity of vadose zone($K_s$) and effective porosity(${\phi}_e$) of undisturbed soil profiles collected at each vadose zone of 6 study areas in South Korea. Effective porosity was approximately 19% of total porosity for each soil profile. Applied to Ahuja's equation, the correlation between $K_s$ and ${\phi}_e$ showed $y=1.3{\times}10^{-7}x^{2.15}(r^2=0.37)$ for total soil profiles. Although the small numbers of soil profile were used for this study, the result of this study might be used for other soil hydraulic studies as reasonable data.

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HBr 가스를 이용한 MgO 박막의 고밀도 반응성 이온 식각

  • 김은호;소우빈;공선미;정지원
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2009년도 제38회 동계학술대회 초록집
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    • pp.212-212
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    • 2010
  • 최근 차세대 반도체 메모리 소자로 대두된 magnetic random access memory(MRAM)에 대한 연구가 활발히 진행되고 있다. 특히 MRAM의 magnetic tunnel junction(MTJ) stack을 구성하는 자성 재료의 건식 식각에 대한 연구에서는 좋은 profile을 얻고, 재층착의 문제를 해결하기 위한 노력이 계속해서 진행되고 있다. 본 연구에서는 photoresist(PR)과 Ti 하드 마스크로 패턴 된 배리어(barrier) 층인 MgO 박막의 식각 특성을 유도결합 플라즈마를 이용한 고밀도 반응성 이온 식각(inductively coupled plasma reactive ion etching-ICPRIE)을 통해서 연구하였다. PR 및 Ti 마스크를 이용한 자성 박막들은 HBr/Ar, HBr/$O_2$/Ar 식각 가스의 농도를 변화시키면서 식각되었다. HBr/Ar 가스를 이용 식각함에 있어서 좋은 식각 조건을 얻기 위한 parameter로서 pressure, bias voltage, rf power를 변화시켰다. 각 조건에서 Ti 하드마스크에 대한 터널 배리어층인 MgO 박막에 selectivity를 조사하였고 식각 profile을 관찰하였다. 식각 속도를 구하기 위해 alpha step(Tencor P-1)이 사용되었고 또한 field emission scanning electron microscopy(FESEM)를 이용하여 식각 profile을 관찰함으로써 최적의 식각 가스와 식각 조건을 찾고자 하였다.

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알콜리즘 환자(患者)의 인격특성(人格特性)에 관(關)한 임상적(臨床的) 고찰(考察) -MMPI와 사상체질(四象體質)을 중심(中心)으로- (Clinical Study on Personality Characteristics of the Alcoholic Patients -with MMPI & Sasang Constitution(四象體質)-)

  • 김종우;김지혁;황의완
    • 동의신경정신과학회지
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    • 제3권2호
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    • pp.65-85
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    • 1992
  • To study the personality characteristics of alcoholic patients, they were screned with the MAST(Michigan Alcoholism Screening Test) and administered with the MMPI (Minnesota Multiphasic Personality Inventory) in the Dept. of Neuropsychiatry, Oriental Medical Hospital in Kyung Hee Univ. form March 1991 to June 1991. Patients admitted for alcoholism were examined and analyzed using the above tests and then studied by Sasang Constitutional approach. Results were as follows; 1. In the MAST score, the cases of obvious alcohol dependence was 53.3% and overall mean score was 28.1 point. 2. In the MMPI scale, the mean of the T-scores for 2(D)-4(Pd) profile was high, but it was not statistically significant. 3. The results obtained by multivariate cluster analysis of MMPI T-scores can be divided into 3 subgroups; 1) 9% showed the psychiatric tendency of F-6(Pa)-9(Ma)profile, 2) 44.2% showed no significant profile, 3)46.5% showed the neurotic tendency of 1(Hs)-2(D)-3(Hy)-4(Pd) profile. 4. Since 44.2% showed no significant profile on the MMPI, much more alcoholic patients were caused not by personality factors but by social tolerance, and also by increasing apportunities of drinking in Korean society. 5. When analyzed with Sasang Constituional approach, 1) for the Soyangin (少陽人): 6(Pa) scale was particularly high, 1(Hs) and 3(Hy) scales were low compared to others, 2) for the Taiumin(太陰人): 1(Hs)-2(D)-3(Hy)-4(Pd) neurotic profile was high, the K-scale and 4(Pd)scale were high compared to the Soyangin, 3) for the Soumin(少陰人): 1(Hs)-2(D)-3(Hy)-4(Pd) neurotic profile and 7(Pt) scale were also high.

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Finite Jerk를 이용한 로봇 구동용 BLDC 모터의 저진동화 (The Vibration Minimization of BLDC Motor driving a robot by using the Finite-Jerk Continuity Acceleration curve)

  • 이동엽;황예;김규탁;정원지
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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    • pp.1144-1146
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    • 2005
  • This paper presents the optimal design reducing the rotor inertia in order to improve the driving characteristic of BLDCM for robots. The parallel Genetic Algorithm is performed to rotor inertia minimization in optimal design. Also, velocity profile with finite jerk method is introduced to reduce vibration of BLDCM. As a result, a torque characteristic is same although rotor inertia is reduced 2/3 compared with prototype model. And, maximum vibration value is reduced by 63.4[%1 according to apply finite jerk.

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Significant Association of Metabolic Indices, Lipid Profile, and Androgen Levels with Prostate Cancer

  • Tewari, Reshu;Chhabra, Mohini;Natu, Shankar Madhavan;Goel, Apul;Dalela, Divakar;Goel, Madhu Mati;Rajender, Singh
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권22호
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    • pp.9841-9846
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    • 2014
  • Objectives: To compare the metabolic indices, lipid profile, androgens, and prostate specific antigen between prostate cancer and BPH and between grades of prostate cancer in a cross-sectional study. Materials and Methods: The study enrolled 95 cases of prostate cancer and 95 cases of benign prostatic hyperplasia (BPH). Prostate gland volume was measured using transrectal ultrasound. We compared insulin, testosterone, dihydrotestosterone, prostate specific antigen levels and lipid profile between prostate cancer of different grades and BPH. Further, prostate cancer patients were classified into low grade and high grade. Unpaired t-test for normally distributed variables and Man-Whitney U test for non-normal variables were used to assess differences. Results: We found that prostate cancer patients had significantly higher levels of insulin, testosterone, PSA, cholesterol, triglycerides, low-density lipoprotein (LDL) and very low-density lipoprotein (VLDL) in comparison to their BPH counterparts. Higher levels of these parameters also correlated with a higher grade of the disease. Conclusions: We conclude that higher levels of insulin, testosterone, PSA, and cholesterol correlate with a higher risk of prostate cancer, and also with a higher grade of the disease.

경북지방 돼지유래 salmonella 속균의 약제내성과 plasmid profile (Antibiotic resistance and plasmid profile of salmonella spp isolated from swine in Kyoungbuk province)

  • 김규태;김원일;김상윤;장영술;김대원;김봉환
    • 한국동물위생학회지
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    • 제23권1호
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    • pp.77-91
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    • 2000
  • This study was conducted to investigate the antibiotic resistance and plasmid profiles of 58 salmonella spp isolated from mesenteric lymphnodes of slaughter pigs in Kyoungbuk province during the period from September 1997 to June 1998. The results obtained are as follow that all isolates were susceptible to amikacin, gentamicin, ciprofloxacin and enrofloxacin, and the majority of isolates were highly susceptible to norfloxacin, colistin, nalidixic acid and apramycin while they were moderately susceptible to kanamycin, cephalothin, chloramphenicol, ampicillin, trimethoprim and penicillin. The majority of isolates were over 90% resistant rates to lincomycin, sulfadimethoxine, vancomycin, methicillin and erythromycin. The plasmid profiles of 58 salmonella spp are developed 1 to 4 fractions, 0.9 to 29.5 Kb molecular range sizes and U strains (45.5%) were showed plasmid profiles by agarose gel electrophoresis. 5 derby harbored 29.5 Kb and 7 Kb, and S schwarzengrund had 14 Kb and 0.9 Kb harboring sizes. Four of 10 S agona and 2 of 4 S typhimurium were harbored 3.1 Kb and n.5 Kb, respectively. Thirty-five untypable strains are developed variable size fractions its showed small size plasmid profile less than 6 Kb and 22 (62.8%) of them had no detectable plasmids.

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