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방류 연어, Oncorhynchus keta 치어의 해양 먹이선택성 (Marine Prey Selectivity of Released Juvenile Chum Salmon (Oncorhynchus keta) During arly Marine Migration in Korean Waters)

  • 권오남;김주경;윤문근;김두호;홍관의
    • 수산해양교육연구
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    • 제26권2호
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    • pp.421-429
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    • 2014
  • We investigated the feeding ecology of juvenile chum salmon (Oncorhynchus keta) during the critical early life stage prey selectivity of juvenile chum salmon during early marine migration in Korean waters at spring 2011. Salmon juveniles and zooplanktons were collected to draw with $20m{\times}5m$ gill net and $300{\mu}m$ mesh zooplankton net at each station on 11th-13th April n 2011. Collected zooplanktons were classified to 5 Phylum, 6 Class, 9 Order 17 Species in this study. Almost 76.4-100% species were classified to Phylum Arthropoda, dominant species was a species out of Hyperia galba of Order Amphipoda, Acartia spp and Paracalanus parvus of Order Calanoida. Collected salmon juveniles were grew up to average 4.7-5.4 cm fork length and average 1.0-1.5 g wet weight in whole station. Fish stomach content (mg/salmon) was heaver to 97.4, 82.4 and 63.2 mg wet weight/salmon in ST 2, 3, 4 than 20.4, 18.9 mg/salmon of ST 1, 5, because there are fish (sand eel, Hypoptychus dybowskii) and Krill (Euphausia) as prey in salmon stomach in ST 2, 3, 4. And ST 2, 3, 4 and 5 were dominated by Amphipoda as Hyperia galba, Themisto japonica and Gammarus sp., but ST 1 was dominated by copepod, because of absence of Amphipoda in the station. Therefore small Amphipoda as Hyperia galba was good prey for just released salmon juvenile in nature.

정지방법이 백침계 오이 '샤프1호'의 생장 및 수량에 미치는 영향 (Effects of Training Methods on Growth and Yield of White Spine Cucumber 'Sharp-1')

  • 최영하;박동금;권준국;이재한
    • 원예과학기술지
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    • 제17권5호
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    • pp.569-571
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    • 1999
  • 백침계 오이 '샤프 1호'의 9월 파종 재배시 저온기(11월~익년 2월)에 다수확할 수 있는 정지방법을 구명코자 2개년간('98~'99)에 걸쳐 시험한 결과, $m^2$당 마디수, 엽면적, 수관 상부의 엽면적 분포비율 및 근중 등은 측지재배구가 가장 많았고, 주지+측지재배구, 주지재배구 순이었다. 총수량 및 상품과(商品果) 수량도 같은 경향 이었다. 유인작업에 소요되는 노동력은 측지재배구가 가장 적었고, 주지재배, 주지+측지재배구 순으로 많았다.

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Thermal Analysis on a Satellite Box during Launch Stage by Analytical Solution

  • Choi, Joon-Min;Kim, Hui-Kyung;Hyun, Bum-Seok
    • International Journal of Aeronautical and Space Sciences
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    • 제4권2호
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    • pp.17-25
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    • 2003
  • Simple methods are developed to predict temperatures of a satellite box during launch stage. The box is mounted on outer surface of satellite and directly exposed to space thermal environment for the time period from fairing jettison to separation. These simple methods are to solve a 1st order ordinary differential equation (ODE) which is simplified from the governing equation after applying several assumptions. The existence of analytical solution for the 1st order ODE is determined depending on treatment of time-dependent molecular heating term. Even for the case that the analytical solution is not available due to the time dependent term, the 1st order ODE can be solved by relatively simple numerical techniques. The temperature difference between two different approaches (analytical and numerical solutions) is relatively small (Jess than $1^{\circ}C$ along the time line) when they are applied to STSAT-I launch scenario. The present methods can be generally used as tools to quickly check whether a satellite box is safe against space environment during the launch stage for the case that the detailed thermal analysis is not available.

부분 무치악 임플랜트 보철 수복시 자연치와의 비고정성 연결형태에 따른 3차원 유한요소법적 연구 (THE THREE-DIMENSIONAL FINITE ELEMENT ANALYSIS OF THE PARTIALLY EDENTULOUS IMPLANT PROSTHESIS WITH VARYING TYPES OF NON-RIGID CONNECTION)

  • 이선아;정재헌
    • 대한치과보철학회지
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    • 제34권1호
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    • pp.101-124
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    • 1996
  • In this study, we designed the finite element models of mandible with varying their connecting types between the prosthesis on implant fixture and 2nd premolar, which were free-standing case(Mf), precision attachment case(Mp), semiprecision attachment case(Ms) and telescopic case(Mt). The basic model of the designed finite element models, which contained a canine and the 1st & 2nd premolar, was implanted in the edentulous site of the 1st & 2nd molar by two implant fixtures. We applied the load in all models by two ways. A vertical load of 200N was applied at each central fossa of 2nd premolar and 1st implant. A tilting load of 20N with inclination of $45^{\circ}$ to lingual side was applied to buccal cusp tips of each 2nd premolar and 1st implant. And then we analyzed three-dimensional finite element models, making a comparative study of principal stress and displacement in four cases respectively. Three-dimensional finite element analysis was performed for the stress distribution and the displacement using commercial software(IDEAS program) for SUN-SPARC workstation. The results were as follows : 1 Under vertical load or tilting load, maximum displacement appeared at the 2nd premolar. Semiprecision case showed the largest maximum displacement, and maximum displacement reduced in the order of precision attachment, free-standing and telescopic case. 2. Under vertical load. the pattern of displacement of the 1st implant appeared mesio-inclined because of the 2nd implant splinted together. But displacement pattern of the 2nd premolar varied according to their connection type with prosthesis. The 2nd premolar showed a little mesio-inclined vertical displacement in case of free-standing and disto-inclined vertical displacement due to attachment in case of precision and semiprecision attachment. In telescopic case, the largest mesio-inclined vertical displacement has been shown, so, the 1st premolar leaned mesial side. 3. Under tilting load, The pattern of displacement was similar in all four cases which appeared displaced to lingual side. But, the maximum displacement of 2nd premolar appeared larger than that of the first implant. Therefore, there was large discrepancy in displacement between natural tooth and implant during tilting load. 4. Under vertical load, the maximum compressive stress appeared at the 1st implant's neck. Semiprecision attachment case showed the largest maximum compressive stress, and the maximum compressive stress reduced in the order of precision attachment, telescopic and free-standing case. 5 Under vertical load, the maximum tensile stress appeared at the 2nd implant's distal neck. Semiprecision attachment case showed the largest maximum tensile stress, and the maximum tensile stress reduced in the order of precision attachment, telescopic and free-standing case. 6. Under vertical load or tilting load, principal stress appeared little between natural tooth & implant in free-standing case, but large principal stress was distributed at upper crown and distal contact site of the 2nd premolar in telescopic case. Principal stress appeared large at keyway & around keyway of distal contact site of the 2nd premolar in precision and semiprecision attachment case, appearing more broad and homogeneous in precision attachment case than in semiprecision attachment case.

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정상인 상악동의 형태에 관한 방사선학적 연구 (A RADIOGRAPHIC STUDY ON THE MORPHOLOGY OF MAXILLARY SINUS IN ADOLESCENTS AND ADULTS.)

  • 고광준;이상래
    • 치과방사선
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    • 제14권1호
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    • pp.17-26
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    • 1984
  • The purpose of this study was radiographic analysis of the morphology of maxillary sinus in adolescents and adults. In order to analize the morphology of maxillary sinus in view point of anteroposterior width of medial wall, vertical distance between antral floor and nasal floor level, anterior extension, distance between antral floor and maxillary 1st molar apex, and types of lower border of maxillary sinus, specialized maxillary projection and periapical view with paralleling technique was taken. The author examined orthopantomograms and intraoral standard views taken from 400 adolescents and adults ranged 15-65 year-old. The obtained results were as follows: 1. The antero-posterior width of medial wall of maxillary sinus was 32.80mm in 15-19 year-old group, 33.86㎜ in 20-24 year-old group, 34.09㎜ in 25-29 year-old group, and 33.67㎜ in 30-65 year-old group, and the left maxillary sinus was somewhat smaller than the right. 2. The vertical distance between antral floor and nasal floor level was 8.49㎜ in 15-19 year-old group, 9.05㎜ in 20-24 year-old group, 8.95㎜ in 25-29 year-old group, and 8.32㎜ in 30-65 year-old group. 3. The order of anterior extension of maxillary sinus were distal half of canine, mesial half of canine, mesial half of 1st premolar, and distal half of 1st premolar. 4. The distance between antral floor and maxillary 1st molar were 4.36㎜ in 15-19 year-old group, 4.77㎜ in 20-24 year-old group, 3.58㎜ in 25-29 year-old group, and 2.33㎜ in 30-65 year-old group. 5. The order of the types of lower border of maxillary sinus were entire downward type, close type, partially downward type, waving type, separating type, and indistinct. In the types of antral floor, there was a tendency to increase the seperating type with age.

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스핀업 유동에서의 비선형 에크만 분출 모형의 성능평가 (Performance Evaluation of Nonlinear Ekman Pumping Models for a Spin-up Flow)

  • 최윤환;서용권
    • 한국해안해양공학회지
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    • 제13권4호
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    • pp.273-281
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    • 2001
  • 본 연구에서는 종횡비가 2인 직사각형 용기에 대한 스핀업 유동을 실험과 수치해석으로 연구하였다. 수치해석에서는 1차-, 2차- 에크만 펌핑 모형을 사용한 경우와 평정을 무시한 경우에 관해 유동장을 구하였으며, 실험에서는 고전적인 PIV 방법을 통하여 속도장을 구하였다. 연구결과, 1차-, 2차- 에크만 펌핑 모형은 실험과 유사하게 나타났으며, 펌핑을 무시한 경우는 상이한 유동양상을 보였다.

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소아 서혜부 탈장의 임상적 고찰 (Clinical Study of Inguinal Hernia in Children)

  • 김경래;김성수;이영택;박용기;최창록
    • Advances in pediatric surgery
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    • 제4권1호
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    • pp.48-54
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    • 1998
  • A total of 335 pediatric inguinal hernias were analyzed at the Department of General Surgery, St. Benedict Hospital, for last 10 years (1986 to 1995). Male patients were predominant(2.25 : 1), and 78.2 % were under 2 years of age. Right side was 1.63 times more frequent than the left. Among the 19 cases of incarcerated hernias, 84 % could be safely reduced preoperatively. Twelve cases(3.6 %) were repaired by the Bassini procedure and 21 cases(6.3 %) by internal ring repair. The majority (90.1 %) however did not require a posterior wall reconstruction. Bilaterality was found in 25 cases(7.5 %), and in 8 cases(2.4 %) subsequent contralateral hernia developed after primary ipsilateral repair. Postoperative complication occurred in 15 cases(4.5 %); scrotal seroma and/or hematoma(3%), wound infection(0.6 %), and pneumonia(0.9 %). In order to reduce the incidents of complications, children with inguinal hernias should be treated by a pediatric surgeon.

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비정상 Navier-Stokes 방정식의 수치해석을 위한 다단계 외재법의 성능 비교 (Comparison of multi-stage explicit methods for numerical computation of the unsteady Navier-Stokes equations)

  • 서용권
    • 대한기계학회논문집B
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    • 제21권2호
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    • pp.202-212
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    • 1997
  • In this study, performance of the multi-stage explicit methods for numerical computation of the unsteady Navier-Stokes equations is investigated. Three methods under consideration are 1 st-, 2 nd-, and 4 th-order Runge-Kutta (R-K) methods. Compared in this estimation is stability, accuracy, and CPU time of each method. The computational codes developed are applied to the two-dimensional flow in a square cavity driven by an oscillating lid. It turned out that at Reynolds number 400, the 1 st-order R-K method is the best, while at 3200 the 2 nd-order R-K is recommended. At higher Reynolds numbers, it is conjectured that the 4 th-order R-K method will be the best algorithm among three due to its highest stability.

Bee Venom 약침과 Sweet Bee Venom 약침의 득기감 특성에 관한 연구 (A Study on the Acupuncture sensation Characteristics of Bee Venom and Sweet Bee Venom)

  • 조나영
    • 대한한의진단학회지
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    • 제23권1호
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    • pp.1-8
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    • 2019
  • Objectives The purpose of this study is to determine if there is a difference in acupuncture sensation depending on the bee venom pharmacopunctures. The study was designed to identify the intrinsic acupuncture sensation of the bee venom pharmacopunctures compared to saline. Methods Bee venom,(BV), Sweet bee venom(SBV), and normal saline were injected in order to the left of ST36 (Joksamni), ST37 (Sang-geoheo), right ST36 (Joksamni), ST37 (Sanggeoheo) each. The order of insertion of the BV, SBV, and normal saline was randomly assigned using a computerized random number table. The questionnaire used in this study was based on the Massachusetts General Hospital Acupuncture Sensation Scale (MASS). Results : BV and SBV was statistically significantly higher than saline in soreness, aching, distention, sharp pain and itchiness. Above this, BV was statistically significantly higher than saline in tingling and throbbing. And SBV was statistically significantly higher than saline in warmth. BV was statistically significantly higher than SBV in ichiness. Conclusion. BV and SBV were mainly strong, heavy, and gave a sharp feeling to the subjects. The results of the study can be used as references for future bee venom pharmacopunctures use. In addition, the results of the study can be used as basic data for clinical trials using bee venom pharmacopunctures.

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비파괴 평가용 직접결합형 1차 미분형 SQUID gradiometer (Direct-coupled First-order SQUID gradiometer for Nondestructive Evaluations)

  • 황윤석;최희석;김진태;이순걸;이동훈;박용기;박종철
    • 한국초전도학회:학술대회논문집
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    • 한국초전도학회 1999년도 High Temperature Superconductivity Vol.IX
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    • pp.161-164
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    • 1999
  • We have fabricated the direct-coupled planar type 1st-order SQUID gradiometers. The gradiometer consists of moats or slots in SQUID loop. It is made by YBa$_2Cu_3O_7$ thin films using pulsed laser deposition method on SrTiO$_3$ single crystal and bi-crystal substrates. We have studied the effects of slots and moats in SQUID loop by measuring the voltage modulation signals under uniform field and 1st-order gradient, and the noise properties under non-shielded environment.

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