• Title/Summary/Keyword: 90 degree

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A Design and Implementation of the Power Amplifier using Linearizer for PCS (선형화 기법을 이용한 PCS용 전력증폭기의 설계 및 구현)

  • 하성재;이민희;민준기;이용덕;김복기;홍의석
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.10C
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    • pp.1027-1031
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    • 2002
  • In this paper, the non linear characteristics of HPA (High Power Amplifier) is improved by using predistorter. Predistorter consists of 0 degree and 90 degree couplers, complementary amplifier, shottky diodes, and attenuators. Gain of the Linearized HPA is 54㏈ at 1960㎒ - 1980㎒. IMD (Inter Modulation Distortion) characteristic shows -58㏈c at 39㏈m/tone ⓐ1.23㎒. The IMD performance of this predistorter is improved by 14㏈.

A Study on the Program Development of Estimating the Elapsed Time Considering the Various Racing Lines on the 90 Degree Corner (직각 코너에서의 레이싱라인에 따른 주행 소요시간 예측 프로그램 개발에 관한 연구)

  • 장성국
    • Transactions of the Korean Society of Automotive Engineers
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    • v.11 no.4
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    • pp.220-225
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    • 2003
  • In this paper, various types of racing line are analyzed for the best time to go through a 90 degree comer. 'Best' means the least time, at the greatest average speed. The comer concerned here has the long straights before and after the corner so that the vehicle is able to n with its maximum speed along the straights. It is shown that both inside and outside driving lines including the modified outside driving lines never beat classical racing line. It is also found that outside driving line is better than inside driving inside driving line as long as there are straight lines before and after the comer.

Turbulent Flow Characteristics using Plane Jet on Impingement Surface (평면제트를 이용한 충돌면에서의 난류유동 특성)

  • 윤순현
    • Journal of Advanced Marine Engineering and Technology
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    • v.22 no.4
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    • pp.429-435
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    • 1998
  • Experiments were conducted to investigate the turbulent flow characteristics from on oblique impingement surface to an plane jet at the jet Reynolds number(Re based on the nozzle width) $3{\times}10^4$ The jet mean velocity and turbulent intensity profiles have been measured along the impingement surface by hot-wire anemometer. The nozzle-to-plate distance(H/B) ranged from 2 to 10 and the oblique angle (a) from 45 to 90 degree. Also the secondary peak of the turbulent intensity was observed at H/B=4 S/B 5 and a=90 degree. It has been found that the stagnation point shifted toward the minor flow region as the oblique angle decreased and the position of the stagnation point nearly coincided with that of the maximum turbulent intensity.

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Measurement of Developing Turbulent Flows in a 90-Degree Square Bend with Spanwise Rotation

  • Choi Young Don;Kim Dong Chul;Lee Kun Hee
    • Journal of Mechanical Science and Technology
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    • v.19 no.7
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    • pp.1503-1516
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    • 2005
  • Mean flow and turbulence properties of developing turbulent flows in a 90 degree square bend with span-wise rotation are measured by a hot-wire anemometer. A slanted wire is rotated into 6 orientations and the voltage outputs from them are combined to obtain the mean velocity and the Reynolds stress components. Combined effects of the centrifugal and Coriolis forces due to the curvature and the rotation of the bend on the mean motion and turbulence structures are investigated experimentally. Results show that the two body forces can either enhance or counteract each other depending on the flow direction in the bend.

The Significance of Transverse Shear on Vibration Damping of 90-degree Unidirectional Laminated Composites (단일방향 $90^{\circ}$적층 보의 횡전단응력이 진도감쇠에 미치는 효과)

  • 임종휘
    • Journal of KSNVE
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    • v.10 no.1
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    • pp.57-63
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    • 2000
  • On the basis of the concept of strain energy-weighted dissipation, an enhanced model for predicting damping in laminates is presented. In this model, the influence of transverse shear on $90^{\circ}$ laminates has been included with those of in-plane stresses on beam. Also, an experimental damping measurement is conducted with changing the length and the thickness of laminated beam specimen for confirmation of the model prediction. The theoretical predictions in $90^{\circ}$laminates were reasonably compared with experimental data. The transverse shear reveals to have an influence on the damping, behavior in $90^{\circ}$ laminates.

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Studies on Methacrylate Finish with Silk Fabrics and their Anticrease (Methacrylate 견직물가공과 방추도개선에 대한 연구)

  • 최병희;이양후
    • Journal of Sericultural and Entomological Science
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    • v.28 no.2
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    • pp.65-73
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    • 1986
  • These studies are carried out to improve silk availability for anticrease by useing methacrylate monomer polymerization method with in silk fiber. For this purpose, degree of anticrease, stiffness and shrinkage of various silk fabrics, included finish or not, after repeat of washings and polyster fabric was compared as standard. The adopted samples are ; 1. Polyester, Georgette, Woven density…90cm-85g/m 2. Silk, Twill, Degumed, Light, Woven density…90cm-90g/m 3. Silk, Twill, Degumed, Heavy, Woven density…90cm-200g/m 4. Silk, Stain, Degumed, Light, Woven density…90cm-90g/m The reached results are as followings. 1. The results of improving on anticrease by the finished method were about ten per cent increase against their original samples. 2. The light density silks showed satisfactory improve for anticrease, but the heavy one remained as rather poor condition. 3. The results for degree of textile stiffness were investigated to make sure reserve their textile feeling and observed to be good condition upon the finish work. 4. Textile shrinkage after the repeat of soap wash was investigated on indivisual test sample and silk fabrics showed more shrinkage than polyester which it seemed to be tentering shrinkage druning their general finishing processes. 5. The investigation showed that anticrease, stiffness and shrinkage of the sample textile were more or less deteriorated regardless silk or polyester by the repeat of washings. These matters are considered that such results were obtained because of the fiber fatigue nature. 6. The report reached that silk textiles should be used by dry cleaning methed after finish of any resin finish to reserve their improved anticrease nature.

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A Study on the degree of satisfaction at Day Care Center's Service among elderly clients (일 주간보호센터 이용노인의 만족도에 관한 조사 연구)

  • Kim, Soon-Young;Kang, Kyung-Sook
    • Research in Community and Public Health Nursing
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    • v.10 no.2
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    • pp.422-434
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    • 1999
  • The purpose of this study was to describe the degree of satisfaction at day care center's services and the degree of relationship between each service and overall satisfaction. The data collection was performed from July 1, 1999 to July 15, 1999. And total 199 elderly clients were interviewed in Koksung-kun. The results of the study is as follows: 1. The percentage of satisfactory response at transport service was 95.2%, food supply 94.3%, bath 93.2%, hair cutting 90.8%, physical therapy 90.2%, medical treatment 89.3%. And oriental medical treatment 82.0%. 2. For question of the degree of satifaction at day care service, the distribution of answer was 75.1% in exellent. 15.5% in good, 3.6% in moderate, 3.6% in poor, 2.1% in most poor. 3. The subjective satisfaction was not significantly different by sex, age, the presence or absence of religious, educational level, the presence or absence of family and economic level. 4. A significant association between the program satisfaction and the subjective satisfaction was observed: odds ratios were 26.9 in food supply, 26.4 in luncheon supply, 17.4 in bath, and 14.5 in hair cutting. The following is suggestion based on results of this study: A service program should be developed to fit conditions of rural elderies by specifically analyzing needs of the elderly.

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Floristic Study of Mt. Baegam (Hongcheon-gun, Gangwon-do) (백암산(강원, 홍천)일대의 관속식물상)

  • Cheon, Kyeong-Sik;Kim, Kyung-Ah;Yoo, Ki-Oug
    • Korean Journal of Plant Resources
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    • v.29 no.2
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    • pp.171-188
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    • 2016
  • This study was carried out to investigate the flora of Mt. Baegam (1,099 m) from March, 2014 to July, 2015. The vascular plants were summarized as 506 taxa, including 90 families, 293 genera, 435 species, 5 subspecies, 58 varieties and 8 forms. Among the investigated 506 taxa, 14 Korean endemic, 16 rare plants and 80 specially designated plants (V degree: 3 taxa, IV degree: 7 taxa, III degree: 22 taxa, II degree: 21 taxa, I degree: 27 taxa) by the Ministry of Environment were also included. The naturalized plants were 36 taxa including 3 ecosystem disturbance wild plant. The urbanization index and percent of naturalized plants species were estimated as 11.2% and 7.1%, respectively. Useful plants of 506 taxa listed consists of 207 taxa (40.9%) of edible plants, 200 taxa (39.5%) of pasture plants, 146 taxa (28.9%) of medicinal plants, 58 taxa (11.5%) of ornamental plants and 15 taxa (3.0%) of timber plants, respectively.

Automatic Product Feature Extraction for Efficient Analysis of Product Reviews Using Term Statistics (효율적인 상품평 분석을 위한 어휘 통계 정보 기반 평가 항목 추출 시스템)

  • Lee, Woo-Chul;Lee, Hyun-Ah;Lee, Kong-Joo
    • The KIPS Transactions:PartB
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    • v.16B no.6
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    • pp.497-502
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    • 2009
  • In this paper, we introduce an automatic product feature extracting system that improves the efficiency of product review analysis. Our system consists of 2 parts: a review collection and correction part and a product feature extraction part. The former part collects reviews from internet shopping malls and revises spoken style or ungrammatical sentences. In the latter part, product features that mean items that can be used as evaluation criteria like 'size' and 'style' for a skirt are automatically extracted by utilizing term statistics in reviews and web documents on the Internet. We choose nouns in reviews as candidates for product features, and calculate degree of association between candidate nouns and products by combining inner association degree and outer association degree. Inner association degree is calculated from noun frequency in reviews and outer association degree is calculated from co-occurrence frequency of a candidate noun and a product name in web documents. In evaluation results, our extraction method showed an average recall of 90%, which is better than the results of previous approaches.

MWCA Test using 90/150 HCA (90/150 HCA를 이용한 MWCA 판정법)

  • Choi, Un-Sook;Cho, Sung-Jin;Kim, Han-Doo;Kim, Jin-Gyoung;Kang, Sung-Won
    • The Journal of the Korea institute of electronic communication sciences
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    • v.14 no.1
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    • pp.235-242
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    • 2019
  • Self-reciprocal polynomials over finite fields are useful in several applications, including reversible codes with read-backward properties. This paper is a study on 90/150 CA with characteristic polynomials of maximal weight polynomials, which is one of the self-reciprocal polynomials. In this paper, we propose a decision method for determining the existence of 90/150 MWCA corresponding to the maximum weight polynomial of degree 2n using n-cell 90/150 CA with transition rule <$100{\cdots}0$>. The proposed method is verified through experiments.