• 제목/요약/키워드: grade band

검색결과 77건 처리시간 0.026초

인가 스트레스에 따른 HFPD의 통계적 패턴해석 (Statistic Pattern Analysis of HFPD According to Applied Stress)

  • 김덕근;이은석;정영일;임장섭;김태성
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 춘계학술대회 논문집 유기절연재료 방전 플라즈마
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    • pp.18-22
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    • 2000
  • The partial discharge testing is widely used in insulation property measurement because it gives low stress to high voltage equipment which is undertaken tests. Therefore it is very useful method compare to previous destructive methods and effective diagnosis method in power transformer that requires live-line diagnosis. But partial discharges have very complex characteristics of discharge pattern so it is required continuous research to development of precise analysis method. In recent, the study of partial discharge is carrying out discover of initial defect of power equipment through condition diagnosis and system development of degradation diagnosis using HFPD(High Frequency Partial Discharge) detection. In this study, simulated transformer is manufactured and HFPD occurred from transformer is measured with broad band antenna in real time, the degradation grade of transformer is analyzed through produced patterns in simulated transformer according to applied voltages.

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PD 측정과 HFPD의 감도특성에 관한 연구 (A Study on the Sensitivities Characteristics in a PD and a HFPD)

  • 임장섭;김덕근
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 춘계학술대회 논문집 유기절연재료 방전 플라즈마
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    • pp.29-32
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    • 2000
  • The partial discharge testing is widely used in insulation property measurement because it gives low stress to high voltage equipment which is undertaken tests. Therefore it is very useful method compare to previous destructive methods and effective diagnosis method in power transformer that requires on-line & on-site diagnosis. But partial discharges have very complex characteristics of discharge pattern so it is required continuous research to development of precise analysis method. In recent, the study of partial discharge is carrying out discover of initial defect of power equipment through condition diagnosis and system development of degradation diagnosis using HFPD(High Frequency Partial Discharge) detection. In this study, simulated transformer is manufactured and PD/HFPD occurred from transformer is measured with broad band antenna in real time, the degradation grade of transformer is analyzed through produced patterns in simulated transformer according to applied voltages.

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여고생의 성에 대한 지식, 태도, 경험 및 성교육 요구 (Knowledge and Attitude toward Sex, Sexual Experience and Need of Sex Education of High School Girls in Taegu)

  • 김언희;정문숙
    • 보건교육건강증진학회지
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    • 제10권2호
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    • pp.40-55
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    • 1993
  • To obtain information about knowledge and attitude toward sex, sexural experience and need of sex education, a questionnaire survey was conducted on 599 students who were attended in 2nd grade of 2 girls' high schools(A group: 190 girls), 2 vocational girls' high schools(B group: 205 girls), and 2 special girls' high school attached to industrial company(C group: 204 girls) in Taegu city between 20th and 25th April 1992. Mean score of knowledge toward sex of the total was 9.3. Mean score of A group was higher than that of Band C groups. Among the total students, vocational high school girls were the highest affirmative attitude towards the acquaintance and relationship with the other sex, and the next was special high school girls. Students of B group assumed the highest negative attitude towards artificial abortion, and the lowest was A group. Among the respondent girls, 31.1% did not experienced in the acquaintance and relationship with the other sex and 86 girls(14.4%) had experience with sexual affairs. Most of girls(96.9% of A group, 90.4% of B group and 86.8% of C group) agreed to necessity of sex education, and answered that current education on sex was insufficient to them(80.6% of A group, 82.6% of B group and 62.4% of C group). Among what the surveyed girls wanted to know about knowledge towards sex, they showed the highest interest on the acquaintance and relationship with the other sex(A group: 44.7%, B group: 45.4%, C group: 56.4%). And they showed the second highest interest on pregnancy and delivery(A group: 33.2%, B group: 32.6% , C group: 26.5%). There was no unique difference among each surveying item. Most of the students(A group: 46.8%, B group: 40.1%, C group: 36.3%) thought it better that the time they wanted to get education on sex in 5th or 6th grade of elementary schools and to have a regular curriculum on sex education.

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초등학교 5~6학년군 수학 교과서와 익힘책의 어휘 적정성 분석 (Analysis of the Adequacy of Vocabulary in Elementary Mathematics Textbooks and Workbooks for Grades 5 and 6)

  • 방정숙;권미선;김정원
    • 대한수학교육학회지:수학교육학연구
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    • 제27권3호
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    • pp.329-350
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    • 2017
  • 본 연구는 초등학교 5~6학년군 수학 교과서와 익힘책에 사용된 어휘의 적정성을 분석하였다. 연구 대상은 5~6학년군 수학 교과서와 익힘책으로, 수학 교과서의 본문 차시, 수학 교과서의 본문 이외 차시, 익힘책의 본문 차시를 분석하였다. 어휘 적정성 분석은 9등급 어휘 체계에 따라 어휘 난이도 측면에서 이루어졌으며, 어휘 빈도 분석도 함께 실시하였다. 어휘 적정성 분석 결과, 교과서 및 익힘책에 제시된 어휘 중 5~6학년 수준보다 높은 등급의 어휘는 10% 미만으로 대부분의 어휘는 5~6학년 학생들의 수준에 적합한 것으로 나타났다. 하지만, 일부 어휘의 경우 학생 수준보다 어휘 수준이 높았으며 어휘의 의미를 맥락상 유추하기 어려운 경우도 있었다. 어휘 빈도 분석 결과, 5~6학년군 수학 교과서의 본문 차시에 공통적으로 방법, 알아보다, 수, 이야기하다, 나타내다 등의 어휘가 많이 사용되었다. 이러한 연구 결과를 토대로 차기 5~6학년군 수학 교과서 개발과 실제 수업 시 적정한 어휘 사용에 관한 시사점을 제공하고자 한다.

Development of SNP marker set for discriminating among Korean rice varieties and imported rice in Korea

  • Park, Seul-Gi;Lee, Hyo-Jeong;Lee, Keon-Mi;Baek, Man-Kee;Park, Hyun-Su;Shin, Woon-Chul;Nam, Jeong-Kwon;Kim, Choon-Song;Kim, Bo-Kyeong;Cho, Young-Chan
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2017년도 9th Asian Crop Science Association conference
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    • pp.154-154
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    • 2017
  • In accordance with the opening of the Korean rice market, this study was focused on establishment of database for discriminating the Korean rice varieties and imported brand rices using DNA markers. In this study, the SNP markers were developed using single nucleotide polymorphisms between the reference sequences of japonica and them of 40 brand rices which collected in Australia, China, Thailand, United States and Vietnam. The developed SNP markers were screened to a total of 360 rices including 320 Korean rice varieties and 40 imported brand rices. We selected polymorphic markers among Korean bred rive varieties and imported brand rices. The selected markers were classified into 3 grades. The markers of A grade produced DNA band in 360 rices of 30~40%, B grades produced in 40~60%, and C grades produced bands over 60% rices. First, we tried to set-up the discriminating system using the minimum SNP markers of A grade. Especially, a set of sixteen SNP markers could identify among Korean bred rice varieties and imported brand rices. Additionally, some SNP markers like NSb for Pib gene, JJ80-T for Pi5 and YL155/YL87 for Pita which linked to resistance genes to blast were used to fingerprinting system. These markers were set-up as multiplex set for enhancing the identification efficiency among rice varieties. Finally, the selected SNP markers would be used to the fluidigm assay to construct the database for elaborate discrimination of rice varieties.

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내반주 변형에 의한 지연성 척골 신경 마비 (Tardy Ulnar Nerve Palsy due to Cubitus Varus Deformity)

  • 전인호;김풍택;박병철;인주철
    • Clinics in Shoulder and Elbow
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    • 제5권1호
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    • pp.29-36
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    • 2002
  • Purpose : Cubitus varus deformity has been reported to cause ulnar neuropathy. We present five cases of tardy ulnar nerve palsy due to cubitus vus and analyzed the factors related to the nerve plasy caused by the deformity. Materials and Methods : Three men and two women were reviewed retrospectively and the mean age of the patients were 26 (range, 14-38). The average interval from initial fracture to nerve palsy was 19 years (8-32 years). The severity of symptoms, according to McGowan's classification, was grade I of 2 patients, grade Ⅱ of 3 patients. Carrying angle was an average of 18。 (30° -45° ). Internal rotation angle measured by Yamamoto's method was an average of 33° (30° -45° ). Results ㆍ The mean follow-up period was 53 months (35-70 months). Elbow pain and numbness of the fingers were relieved shortly after surgery. It revealed that anterior subluxation of the nerve due to internal rotation deformity and compression of the nerve between the medially shifted medial head of triceps and the medial epicondyle. Conclusion : The major entrapment point of the nerve is the fibrous band between the two heads of the flexor carpi ulnaris. The severe internal rotation deformity may contribute the cause of tardy ulnar nerve palsy in cubitus varus deformity.

포토레지스트 스트리퍼 폐액으로부터 고순도 유기용제 회수 (Reclamation of High Purity Organic Solvents from Waste Photoresist Stripper)

  • 김대진;오한상;김재경;박명준;이문용;구기갑
    • 청정기술
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    • 제13권4호
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    • pp.257-265
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    • 2007
  • 반도체 공정에서 배출되는 폐 포토레지스트 스트리퍼(photoresist stripper)의 주성분인 NMP (N-methy-pyrrolodione)와 BDG (Butyldiglyrcol)를 회수하여 재활용할 목적으로 나선형 스핀밴드시스템(spinning band stem)이 장착되어 있는 진공증류장치를 이용하여 실험실적 규모의 증류실험을 수행하였다. 정제된 NMP와 BDG의 순도는 포토레지스트 스트리퍼용 용제 기준 물성치인 순도 99.5% 이상이었고, 수분 1000 ppm 이하, 색도(APHA) 50 이하, 나트륨 성분을 제외한 대부분의 금속성분은 1 ppb 이하로 반도체용 스트리퍼 용액 제조에 재활용할 수 있는 수준임을 확인하였다. NMP와 BDG의 회수을은 PR스트리퍼 폐액 A 타입의 경우 NMP 96%, BDG 53%, B 타입의 경우 NMP 93%, BDG 57%이었다.

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공조용 로터리 압축기의 소음 저감에 관한 연구 (A Study on Noise Reduction of Rotary Compressor)

  • 안병하;김영수
    • 동력기계공학회지
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    • 제3권3호
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    • pp.60-69
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    • 1999
  • The noise and vibration sources of rotary compressor for room air-conditioner are pressure pulsation of compression process, cavity resonance of inner space, structural radiation noise of shell and impact noise of discharge valve. Among them, pressure pulsation is very important noise and vibration source. Because it transferred various kinds of noise and vibration like as mentioned above. In this reason, muffler and resonator are used in order to absorb and remove these noises. But an analytical prediction using acoustic analysis does not coincident with the experimental result. The difference between analysis and actual state is due to the assumption of analysis. This paper covered with new concept of muffler design based on the turbulence kinetic energy of flow by using CFD. From this analysis, it is possible to decide the best position of discharge port of muffler. Therefore $2{\sim}3dB$ noise reduction effect is acquired in rotary compressor of 5000 BTU grade. Also new approach of resonator design is suggested. From this study, the characteristics of resonator and surge hole (a kind of resonator without pipe length) are identified. The former is useful for pure tone noise (narrow frequency band), and the latter is effective for broad frequency band. This paper shows that it is very available to use 3 dimensional analysis of resonator in order to predict more exact tuning frequency. The result is proved by a lot of experiments. From combination of fluid analysis and acoustic analysis, up stream position is effective location of resonator concerning turbulence motion of fluid.

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Back-Projection을 활용한 홍삼 내부 측정 시스템 (A Red Ginseng Internal Measurement System Using Back-Projection)

  • 박재영;이상준
    • 정보처리학회논문지:소프트웨어 및 데이터공학
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    • 제7권10호
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    • pp.377-382
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    • 2018
  • 본 연구는 홍삼 등급 판정을 위한 내부 상태 및 조직의 치밀도 분석 방법에 관한 것이다. 홍삼 내부 측정을 위해 1990년대 이후부터는 자기공명영상법(MRI), X-ray 판별 등의 비파괴 검사 방법에 대한 연구가 다양하게 이루어졌지만, 등급 판정에 가장 중요한 내공(內空), 내백(內白)을 파악하는데 어려움이 있어 정확한 내부 판정이 불가능하였다. 그리하여 본 연구에서는 적외선 조명 환경의 폐쇄형 영상 취득 장치를 제작하고 내공, 내백의 유무와 직경을 파악할 수 있는 내부 측정 시스템을 개발하였다. 제작한 장치는 홍삼 내부 투과율이 높은 950nm 파장대역의 적외선 조명, 적외선 대역 촬영이 가능한 카메라, 카메라에 홍삼의 초점을 자동제어 할 수 있는 Y축 제어 액추에이터 그리고 홍삼을 $1^{\circ}$의 간격으로 $360^{\circ}$ 회전하며 영상을 취득할 수 있는 회전 액추에이터로 구성이 되어있다. 제안하는 알고리즘은 Y축 액추에이터에서 Auto-Focus 알고리즘을 수행하여 홍삼의 크기와 두께 변화에 따라 객체의 선명한 초점을 자동으로 맞춰준다. 그다음 홍삼을 $1^{\circ}$ 간격으로 $360^{\circ}$ 회전하며 총 360장의 홍삼 영상을 취득하면 라돈 변환(Radon transform)을 통해 사이노그램(Sinogram)으로 재구성하고, 역 라돈 변환(Inverse Radon transform)을 통해 단층영상복원(Back-projection) 알고리즘이 수행되어 홍삼 내부 영상을 획득하였다. 알고리즘 수행 결과 홍삼 두께나 모양에 관계없이 내부 단면영상 획득이 가능하였고 영상을 통해 내공, 내백의 유무와 직경을 파악할 수 있었다. 추후 10,000개 이상의 다양한 모양과 크기를 가지는 홍삼에 대하여 내부 영상을 취득하여 등급 판별 기준을 적용한다면 신뢰성 있는 홍삼 등급 자동화 측정 방법으로 사용가능 할 것이다.

Spectral Analysis of Heart Rate Variability during Treadmill Exercise at Various Speeds and Grades

  • Kim, Hyeong-Jin;Kim, Ki-Hong;Ahn, Dong-Kuk;Park, Jae-Sik
    • The Korean Journal of Physiology
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    • 제30권1호
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    • pp.43-51
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    • 1996
  • This study was aimed to elucidate the changes in heart rate variability during treadmill exercise at various speeds and grades by spectral analysis. Thirty-three untrained male college students aged $20{\sim}26\;yr $were employed to exercise on a treadmill using 4 speeds (4.02, 5.47, 6.76 and 8.05 km/h) and 6 grades (0, 4, 8, 12, 16 and 20%). A fixed speed was selected for each session with the grade increased every 3 min. The electrocardiogram, respiration and the stepping activity were continuously recorded through an A/D converter system on the computer disk. Power spectra of heart rate variability (RRV) were obtained by use of a fast Fourier transform algorithm. The frequency domain was divided into 3 bands: $VLF\;(0{\sim}0.04\;Hz),\;LF\;(0.04 {\sim}0.15\;Hz)\;and\;HF\;(0.15{\sim}1.00\;Hz).$ Heart rate was $74.4{\pm}2.1\;beats/min$ at rest and showed a steady increase during treadmill exercise with increasing speed and grade up to $196.7{\pm}5.0\;beats/min.$ Total power of HRV was $35.0{\pm}6.7\;(beats/min)^{2}$ at rest and progressively decreased during exercise down to $1.9{\pm}0.3\;(beats/min)^{2}.$ The %VLF power of HRV was $34.5{\pm}3.7\; %$ at rest and showed no significant change during exercise except for a decrease observed at the highest intensity of exercise. The %LF power was $44.1{\pm}3.0\;%$ at rest and showed a progressive decrease down to $4.5{\pm}1.0\;%$ during those stages of exercise where heart rate was over 135 beats/min. The %HF power was $21.4{\pm}2.9\;%$ at rest and showed a progressive increase up to $87.1{\pm}6.7\;%$ during higher intensity exercise where heart rate was over 165 beats/min. Peak frequency of HF band was $0.200{\pm}0.018\;Hz$ at rest and was shifted to higher frequencies up to $0.909{\pm}0.048\;Hz$ at heart rates greater than 135 beats/min. Respiratory frequency was $18.0{\pm}1.5$ breaths/min at rest and significantly increased during exercise up to $53.0{\pm}3.7$ breaths/min. Stride frequency during treadmill exercise showed an increasing tendency with increasing speed from $55.6{\pm}0.9$ steps/min at 4.02 km/h to $81.2{\pm}0.6$ at 8.05 km/h. It was concluded that total power of HRV decreased progressively with increasing exercise intensity due to the withdrawal of parasympathetic activity. At higher exercise intensity, % LF power decreased and %HF power increased with its peak frequency shifted to higher values in a progressive mode with increasing speed and grade, reflecting a readjustment in the cardiovascular system and the increased respiration and its rate, respectively.

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