• 제목/요약/키워드: percent frequency effect

검색결과 110건 처리시간 0.023초

출력 전압 맥동감소를 위한 직렬공진형 변환기의 제어기 설계 (Controller Design of the Series Resonant Converter for Reducing Output Voltage Ripple)

  • 김만고;한재원;윤명중
    • 대한전기학회논문지
    • /
    • 제37권6호
    • /
    • pp.376-382
    • /
    • 1988
  • A small-signal low-frequency disturbance of the input line affects the regulated-output voltage of the series resonant converter. To mitigate the detrimental effect, the output feedback PI-controller is employed. Small-signal linear models are represented to characterize the closed loop series resonant converter system. Design equations for the PI-controller which satisfy stability and percent ripple conditions are derived from the closed-loop linear model. Experimental results are presented which show excellent correlation with theory.

  • PDF

Identification of Novel SNPs with Effect on Economic Traits in Uncoupling Protein Gene of Korean Native Chicken

  • Oh, J.D.;Kong, H.S.;Lee, J.H.;Choi, I.S.;Lee, S.J.;Lee, S.G.;Sang, B.D.;Choi, C.H.;Cho, B.W.;Jeon, G.J.;Lee, H.K.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제19권8호
    • /
    • pp.1065-1070
    • /
    • 2006
  • The avian uncoupling protein (avUCP) is a member of the mitochondrial transporter superfamily that uncouples proton entry in the mitochondrial matrix from ATP synthesis. The sequencing analysis method was used to identify nucleotide polymorphisms within the avUCP gene in Korean native chicken (KNC). This study identified ten single nucleotide polymorphisms (SNPs) in the avUCP gene. We analyzed the SNPs of the avUCP gene to investigate whether polymorphism in the gene might be responsible for quantitative variations in economic traits in KNC. Three significant polymorphic sites for economic traits were avUCP C+282T (mean body weight, p<0.05), avUCP C+433T (daily percent lay, p<0.05), and avUCP T+1316C (daily percent lay, p<0.05). The frequency of each SNP was 0.125 (C+282T in avUCP gene exon 1 region), 0.150 (C+433T in avUCP gene intron 1 region), and 0.15 (T+1316C in avUCP gene exon 3 region), respectively. Among the identified SNPs, one pair of SNPs (genotype CC, C+282T and TT, avUCP C+433T) showed the highest daily percent lay (p<0.05) and mean body weight (p<0.05) and the frequency was 0.067. This study of the avUCP gene could be useful for genetic studies of this gene and selection on economic traits for KNC.

평형식진동탄환암거천공기의 연구(II) -모수실험 : 진동에 대하여- (A Study on Balanced-Type Oscillating Mole Drainer (II) (Model Test For Vibration))

  • 김용환
    • 한국농공학회지
    • /
    • 제17권4호
    • /
    • pp.3962-3969
    • /
    • 1975
  • 1. When the frame of the experimental apparatus was directly fixed on the platform, result from the spectrum density analysis showed that the generated vibration frequecy of the system was nearly-same as the system's own characteristic vibration frequency, 80Hz, in the case of the forcing vibration frequency was 7.5 to 22.5Hz. The reduction ratio of acceleration by balanced type model compare to non-balanced type one was 26.66 percent. 2. When the frame of experimental apparatus was fixed on the platform with putting a shock absorbing rubber between the frame and the platform, the generated vibration frequency of the system was same as forcing vibration frequency. When either frequency or the amplitude of the forcing vibration was increased, the acceleration ratio was increased too. The average reduction ratio was resulted 44.77 per cent. It was concluded that this method of acceleration measurement(the method using a shock absorbing rubber) was a reaonable method, because actual machine will work under such condition. As the vibration frequency and aptitude were increased, the absolute magnitude of acceleration was increased. 3. unbalanced rotating parts, and unbalanced moment of inertia of links were supposed to be causing factors of residual vibration in spite of using the balanced type oscillating mole drainer. This fact suggested that the attachment of the counter weight on the rotating parts which satisfy the condition mw$.$rw=m0e, was necessary. And also, it was expected that the shock absorbing effect could be improved by putting the shock absorbing materials between the moving parts and their supports.

  • PDF

Strain gradient theory for vibration analysis of embedded CNT-reinforced micro Mindlin cylindrical shells considering agglomeration effects

  • Tohidi, H.;Hosseini-Hashemi, S.H.;Maghsoudpour, A.;Etemadi, S.
    • Structural Engineering and Mechanics
    • /
    • 제62권5호
    • /
    • pp.551-565
    • /
    • 2017
  • Based on the strain gradient theory (SGT), vibration analysis of an embedded micro cylindrical shell reinforced with agglomerated carbon nanotubes (CNTs) is investigated. The elastic medium is simulated by the orthotropic Pasternak foundation. The structure is subjected to magnetic field in the axial direction. For obtaining the equivalent material properties of structure and considering agglomeration effects, the Mori-Tanaka model is applied. The motion equations are derived on the basis of Mindlin cylindrical shell theory, energy method and Hamilton's principal. Differential quadrature method (DQM) is proposed to evaluate the frequency of system for different boundary conditions. The effects of different parameters such as CNTs volume percent, agglomeration of CNTs, elastic medium, magnetic field, boundary conditions, length to radius ratio and small scale parameter are shown on the frequency of the structure. The results indicate that the effect of CNTs agglomeration plays an important role in the frequency of system so that considering agglomeration leads to lower frequency. Furthermore, the frequency of structure increases with enhancing the small scale parameter.

顔面痙攣患者 29例에 대한 臨床的 考察 (The Clinical Observation on 29 Cases of Patients with Hemifacial Spasm)

  • 정동환;심상희;유미경;김종한;박수연;최정화
    • 한방안이비인후피부과학회지
    • /
    • 제17권3호
    • /
    • pp.88-94
    • /
    • 2004
  • Hemifacial spasm is painless uncommon disorder characterized by involuntary paroxysmal movement of one side face. In the treatment of hemifacial spasm, the Western operation or non-operation therapy has many side effect such as hearing loss, exudative otitis media, facial paralysis etc. So we studied mainly the effect of cause, treatment frequency, diseased part of 29 cases with hemifacial spasm for effective clicical application of oriental medicine. The results of study are as follow; 1. It shows more female patients than male patients, and mostly patients in their forties. 2. The diseased part is shown more on left side than right side, and the left side hemifacial spasm is cured more effective. 3. The causes of hemifacial spasm are mainly stress, ignorance, overwork, and the stress, a cold are more effective causes than ignorance in. 4. The disease period is mainly within six months, and that period is the most effective time. 5. The palpebral site is the most frequent site, ineffective site. 6. The effect go with the treatment frequency is not available. 7. There is a 55 percent improvement of 29 cases.

  • PDF

후기 황체기 불쾌기분 장애의 평가 방법 및 진단에 관한 예비 연구 - 정신과 외래환자를 대상으로 - (A Preliminary Study on Method for Evaluation and Diagnosis of Late Luteal Phase Dysphoric Disorder in Women - Focusing on Psychiatric Outpatients -)

  • 이상규;조숙행;곽동일
    • 정신신체의학
    • /
    • 제3권2호
    • /
    • pp.115-125
    • /
    • 1995
  • Reports about the prevalence of premenstrual symptoms state that occurs in 20 to 100% of most reproductive-age women. There is a close association between premenstrual syndrome and affective disorders as well as same some other psychiatric disorders. Late luteal phase dysphoric disorder (LLPDD) is a premenstrual condition defined in DSM-III-R by severe mood changes and other symptoms that repeatedly occur only in the luteal phase of the menstrual cycle. However, DSM-III-R does not specify how to compute the change from the follicular to the luteal phase or how to determine when the amount of change is great enough to warrant the diagnosis nor how to determine occupational or social functional impairment. This study was conducted to evaluate the nature, severity and magnitude of premenstrual syndrome in women with current psychiatric disorders by using prospective Daily Rating Form(DRF), and to measure symptom changes according to three scoring methods for diagnosing LLPDD. Our study obtains the data about premenstrual changes estimated by DRF from 22 women with psychiatric disorders who had met criteria for major depressive syndrome on the Premenstrual Assessment Form (PAF). The data was scored by each three methods and was determined to meet criteria A for LLPDD. The results are as follows: 1) the subjects, when scored according to the percent change method, effect size method and absolute severity method, met the DSM-III-R criteria A for LLPDD in 36.4% (8 subjects), 14% (3 subjects) and 4.5% (1 subject) of the cases respectively. 2) The items of irritability, anger and impatience were occurred most frequently on the DRF, when it was scored according to the three scoring methods. And the item of breast pain was next frequent according to the effect size method and the percent change method but according to the absolute severity method. 3) The PAF item of impaired social functioning was reported by 16 (73%) of the subjects. 4) 4 (18%) of the subjects met criteria A for LLPDD and reported impaired social functioning. The prevalency of LLPDD according to each method varied. The percent change method yielded the greatest (36.4%), and the absolute seventy method yielded the laest (4.5%), The effect size method yielded an intermediate frequency (14%). Therefore, for maximizing the diagnostic accuracy of LLPDD, a diagnostic procedure including a measure of change (e.q., effect size method, percent change method) as well as confirmed diagnosis by DRF, will be needed. Also, an accurate tool to evaluate impaired social functioning will be required.

  • PDF

광물탐사를 위한 진동수영역 유도분극 물리검층 (Geophysical Logging of Frequency-domain Induced Polarization for Mineral Exploration)

  • 신승욱
    • 지구물리와물리탐사
    • /
    • 제24권3호
    • /
    • pp.73-77
    • /
    • 2021
  • 유도분극법은 분극된 광물 입자와 공극을 채우는 지하수의 계면에서의 전기화학적 반응 차이를 영상화시키는 기술로서 광물탐사와 수리지질학적 조사에서 유용하다. 진동수영역 유도분극법은 시간영역 유도분극탐사법보다 더 나은 품질의 자료를 얻을 수 있지만 긴 자료취득 시간 때문에 현장 탐사에서 활발하게 적용되지 않았다. 하지만 현재 광물탐사 프로젝트는 과거와 비교하여 심부에 있거나 품위가 낮은 광체로 탐사 대상이 바뀜에 따라 고품질의 탐사법을 사용하는 것이 중요하다. 또한 자동 계측에 의해 단축된 탐사 시간은 진동수영역 유도분극탐사법의 현장 적용 가능성을 높였다. 따라서 이 연구는 광물탐사에서 광체 탐지 적합성을 파악하기 위하여 국내 스카른 광상의 탐사 시추공을 대상으로 진동수영역 유도분극 물리검층을 수행했다. 심도별 서로 다른 두 진동수에서 측정된 임피던스 자료로부터 교류 전기비저항, 백분율 진동수 효과, 금속계수를 계산했다. 자철석과 황철석을 포함하는 구간은 다른 구간과 비교하면 상대적으로 낮은 교류 전기비저항, 높은 백분율 진동수 효과, 큰 금속계수를 보였다. 따라서 진동수영역 유도분극법은 앞으로의 광물탐사에서 유용할 것으로 여겨진다.

공진 주파수를 고려한 차량 섀시 부품의 피로해석 (Fatigue Analysis of Vehicle Chassis Component Considering Resonance Frequency)

  • 이상범;임홍재
    • 한국공작기계학회논문집
    • /
    • 제13권6호
    • /
    • pp.94-101
    • /
    • 2004
  • The purpose of this raper is to assess the benefits of frequency domain fatigue analysis and compare it with more conventional time domain techniques. The multi-body dynamic analysis, FE analysis and fatigue life prediction technique are applied for the frequency domain fatigue analysis. To obtain the dynamic load history used in the frequency domain fatigue analysis, the computer simulations running over typical road Profiles are carried out by utilizing vehicle dynamic model. The fatigue life estimation for the rear suspension system of small-sized passenger car is performed by using resonance durability analysis technique, and the estimation results are compared with the conventional quasi-static durability analysis results. For the pothole simulation, the percent changes, of the fatigue life between the two durability analysis techniques don't exceed 10%. But for the Belgian road simulation because of the resonance effect, the fatigue life using the resonance durability analysis technique are much smaller estimated than the quasi-static durability analysis results.

방사선 조사시의 수도종자의 수분함량과 산소와의 관계 (Post-Irradiation Oxygen Effect of Rice Seeds in Varying Seed Water Content)

  • 이영일;최광태
    • 한국작물학회지
    • /
    • 제20권
    • /
    • pp.69-73
    • /
    • 1975
  • 방사선후처리로서 산소가 수분함량이 다른 수도종자에 미치는 영향을 조사코저 수분함량 5.6∼14.7%까지의 종자에 3∼25kR의 방사선량을 조사한 후 산소 및 질소로 bubbling한 상태에서 hydration처리하였다. 효과가 현저하여 5.6∼12.9%까지는 산소처리에 의한 묘장 및 생존율의 감소가 나타났지만 13.9%부터 그 이상에서는 차이가 없었다. 엽록소돌연변이율 및 불임율은 6.5%의 저수분에서 13.0%의 고수분함량에 이르기까지 공히 산소처리에 의한 영향이 있었고 특히 저수분함량일수록 또는 방사선량이 높을수록 그차이는 현저하였다.

  • PDF

CANDU형 핵연료 채널 압력관에 대한 원거리장 와전류의 자제분포 특성해석(I) (A FEM Analysis of Remote Field Eddy Current Distribution Characteristics to CANDU Fuel Channel Tube(I))

  • 허형;정현규;김건중
    • 비파괴검사학회지
    • /
    • 제22권1호
    • /
    • pp.59-64
    • /
    • 2002
  • CANDU형 핵연료채널 압력관(Zr-2.5%Nb)과 calandria관(Zircaloy-2)에 대한 원격장 와전류탐상의 자계분포특성을 파악하기 위하여 유한요소 해석을 수행하였다. 압력관과 칼란드리아관의 전자기장 분포와 위상각 해석을 통하여 최적 검사 주파수와 감지코일의 위치를 평가하였다. 또한 축대칭 구조물(Al-ring과 Al-block)이 공존시 파라미터해석을 통하여 원격장 와전류의 특성을 평가하였다.