• 한국정밀공학회지
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• 제17권1호
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• pp.145-152
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• 2000

X-ray diffraction method detects change of crystal lattice distance under material surface using diffraction angle 2$\theta$. This technique can be applied to the behavior on slip band and micro crack due to material degradation. The relation between half-value breadth and number of cycle has three stages which constitute rapid decrease in initial number of cycles, slight decrease in middle number of cycles and rapid decrease in final number of cycles. The ratio of half-value breadth takes a constant value on B/B$_{0}$-N diagram with loading condition except early part of fatigue life. The ratio of half-value breadth B/B$_{0}$ with respect to number of cycle to failure N$_{f}$ has linear behavior on B/B$_{0}$-log N$_{f}$ diagram. Therefore, in this paper the estimation of fatigue life by average gradient method has much less estimated mean error than the estimation of fatigue life by log B/B$_{0}$-log N/N$_{f}$ relation.elation.ation.

• 정보처리학회논문지B
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• 제16B권3호
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• pp.233-238
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• 2009

자질 수가 적은 소규모 크기 문서들의 자동분류는 좋은 성능을 얻기 어렵다. 그 이유는 문서집단 전체의 자질 수는 크지만 단위 문서 내 자질 수가 상대적으로 너무 적기 때문에 문서간 유사도가 너무 낮아 우수한 분류 알고리즘을 적용해도 좋은 성능을 얻지 못한다. 특히 웹 디렉토리 문서들의 자동분류에서나, 디스크 복구 작업에서 유사도 평가와 자동분류로 연결되지 않은 섹터를 연결하는 작업에서와 같은 소규모 크기 문서의 자동분류에서는 좋은 성능을 얻지 못한다. 따라서 본 논문에서는 소규모 크기 문서의 자동분류에서의 문제점을 해결하기 위해 분류 사전작업으로, 예제기반 자질 필터링 방법 Relief-F알고리즘을 소규모 문서 내 자질 필터링에 적합한 ERelief-F 알고리즘을 제시한다. 또 비교 실험을 위해, 기존의 자질 필터링 방법 중 Odds Ratio와 정보이득, 또 Relief-F 알고리즘을 함께 실험하여 분류결과를 비교하였다. 그 결과, ERelief-F 알고리즘을 사용했을 때의 결과가 정보이득과 Odds Ratio, Relief-F보다 월등히 우수한 성능을 보였고 부적절한 자질도 많이 줄일 수 있었다.

• 한국수산과학회지
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• 제8권1호
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• pp.7-10
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• 1975

제주도 고등어 자망어업의 주어기인 1974년 5월 28일부터 8월 31일까지 서귀포와 비양도근해어장에서 고등어 자망어구의 이망율에 관한 시험조업결과는 다음과 같다. 1. $X^2$ t 검정에 의하면 고등어 nylon-monofilament 자망 B형이 nylon-multifilament 자망 A형보다 이망성능이 우위하고 나망율비는 $m_A:m_B=1:1.8$이다. 2. 망목 75mm인 nylon-monofilament 자망 C형, D형이 망목 85mm인 nylon-monofilament 자망 E형 F형 보다 이망성능이 우위하고 이망율비는 $m_E{\cdot}F:m_C{\cdot}D=1:2.8$이다. 3. 망계 굵기가 120tex와 75tex이고 망목이 75m 및 85mm인 C, D, E, F, 형에서는 상호간의 우위는 모두 확인할 수 없었다.

• 한국환경보건학회지
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• 제10권1호
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• pp.99-106
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• 1984

The diets used to this experiment were composed only of stock diet for group A, a mixture of stock diet and 2% cholesterol for group B, and 5%, 10% perilia powder for group C, D and 5%, 10% pine nut for group E, F in addition to group B diet respectively. All groups fed with these experimental diets for 3 weeks were fasted for 15 hours at the end of the experiment, and then they were decapitated to take serum. The serum was used to measure the level of glucose, total cholesterol, triglyceride, HDL-cholesterol and lipoprotein composition. The results were summarized as follows. 1. Perilla and pine nut diets have no influence on body weight and food intake in cholesterolfed male rats 2. The blood glucose level was not changed significantly at groups C-F. 3. Total cholesterol level was significantly decreased by 21.6% ~ 29.7% at group C-F than at group B. 4. HDL-cholesterol level was increased by 51.3% ~ 86.1% at group C-F than at Group B. 5. The $\alpha/\beta$ ratio which is 0.51 at the group A was risen to 0.99 at the group B. However, this ratio was decreased to 0.5 0 - 0.51 at group C, D and to 0.68 - 0.69 at group E.F.

• 한국전기전자재료학회논문지
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• 제13권8호
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• pp.675-680
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• 2000

In this study the temperature coefficient of resonant frequency(TC $F_{r}$) dielectric and piezoelectric properties of Pb[(S $b_{1}$2//N $b_{1}$2/)$_{0.065}$)-(Z $r_{x}$, $Ti_{1-x}$ )$_{0.90}$] $O_3$ceramics were investigated with Zr/Ti ratio. The compositions near the morphotropic phase boundary (MPB) appeared when Zr/Ti ratio was 49.5/50.5 The dielectric constant and electromechanical coupling factor( $k_{p}$) also showed the highest values of 1,257, 0.653 respectively when the Zr/Ti ratio was 49.5/50.5 Moreover the mechanical quality factor( $Q_{m}$) showed th lowest value of 713 when the Zr/Ti ratio. The temperature coefficient of resonant frequency(TC $F_{r}$) abruptly change at the morphotropic phase boundary(MPB) which existed between the rhombohedral phase with highly negative TC $F_{r}$ of -106ppm/$^{\circ}C$ and the tetragonal phase with highly positive TC $F_{r}$ of +64pp $m^{\circ}C$ as Zr/Ti ratio varied from 50/50 to 49.5/50.5.50.5..50.5.

• ETRI Journal
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• 제36권3호
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• pp.510-513
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• 2014

A Q-band pHEMT image-rejection low-noise amplifier (IR-LNA) is presented using inter-stage tunable resonators. The inter-stage L-C resonators can maximize an image rejection by functioning as inter-stage matching circuits at an operating frequency ($F_{OP}$) and short circuits at an image frequency ($F_{IM}$). In addition, it also brings more wideband image rejection than conventional notch filters. Moreover, tunable varactors in L-C resonators not only compensate for the mismatch of an image frequency induced by the process variation or model error but can also change the image frequency according to a required RF frequency. The implemented pHEMT IR-LNA shows 54.3 dB maximum image rejection ratio (IRR). By changing the varactor bias, the image frequency shifts from 27 GHz to 37 GHz with over 40 dB IRR, a 19.1 dB to 17.6 dB peak gain, and 3.2 dB to 4.3 dB noise figure. To the best of the authors' knowledge, it shows the highest IRR and $F_{IM}/F_{OP}$ of the reported millimeter/quasi-millimeter wave IR-LNAs.

• Journal of Chest Surgery
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• 제13권1호
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• pp.26-33
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• 1980

The incidence of the empyema thoracis has been drastically reduced with the advent of antimicrobial drugs. Empyema thoracis is however still dealt with one of major problems in thoracic surgery because of difficulties in the management of associated bronchopleural fistula. During the period of January 1975 to June 1979, 145 patients of empyema thoracis were treated in the Department of Thoracic Surgery, Busan National University Hospital. This reports dealed especially with the incidence, etiology and management of chronic empyema thoracis with B.P.F. and estimated the results of intercostal myoplasty. The results: 1 ] Among 145 empyema thoracis patients, 33 patients [22.7%] had bronchopleural fistula. 2] Male predominated in general with the ratio of 4:1 and in empyema thoracis with B.P.F. male predominance was further more prominent with the ratio of 10:1. Peak incidence of chronic empyema thoracis lay on 3rd and 4th decade. 3] The most common causation of empyema thoracis was pneumonia [77.3%] in children and tuberculosis [48.8%] in adult. 4] The most common causative organism of empyema thoracis was staphylococcus aureus [52.5%]. 5] Among 40 cases of resection for pulmonary tuberculosis, 4 cases developed empyema thoracis with B.P.F. [10%], and resection for another underlying pathology was 2.1%. 6] In contrast to good prognosis of acute empyema thoracis, chronic empyema thoracis with B.P.F. was improved only 66.6% of cases. 81.5% of chronic empyema without B.P.F. were cured completely. 7] Intercostal myoplasty were performed in 21 cases of empyema thoracis with B.P.F. and of which 15 cases showed that fistula were closed. 8] The over all mortality rate in empyema thoracis was 8.7%. The mortality rate of chronic empyema thoracis with and without B.P.F. was 15.2% and 5.3% respectively.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제55권8호
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• pp.403-407
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• 2006

Standard capacitors, as like as Hamon resistor standards, of series connection/parallel connection ratio $10{\mu}F/1000{\mu}F\;and\;100{\mu}F/10000{\mu}F$ were fabricated for calibration of impedance bridges or analyzers with measuring ranges up to 1 F. The calculated correction terms to the ratio of one measured value in series connection to the value in parallel connection were evaluated to be $1.92{\times}10^{-7}$. These capacitors were designed to be used not only as 100:1 capacitance standards but also as single capacitors or decade capacitors with decade values at frequencies up to 1 kHz.

• Asian-Australasian Journal of Animal Sciences
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• 제11권2호
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• pp.185-191
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• 1998

A total of 240 weaned pigs (BW 5.4 kg) were allotted in a completely randomized block design to find out the optimum lactose : sucrose ratio for the weaned pigs. Treatments were 100:0 (A), 75:25 (B), 50:50 (C), 25:75 (D) and 0:100 (E) in lactose : sucrose ratio. For the first week after weaning, average daily gain (ADG) and feed/gain (F/G) were improved (p < 0.05) for pigs fed A, B and C diets compared to pigs fed diets D and E, but the average daily feed intakes (ADFI) of the pigs were not different. From d 7 to 14, no significant differences was found in ADG and ADFI among the treatments, but pigs fed the diets A, B and C had improved F/G compared with the pigs fed diets D and E (p < 0.05). From d 15 to 21, no significant differences were found in ADG, ADFI and F/G among the treatments. The digestibility of nutrients was not influenced by the lactose : sucrose ratio except nitrogen. Nitrogen digestibility of A diet was significantly higher than D and E diets (p < 0.05) but no significant differences were found among diets A, B and C. Dry matter and phosphorus excretions were not influenced by the treatments. The pigs fed diets A, B and C excreted significantly less nitrogen than the pigs fed diets D and E. In conclusion, the results suggest that sucrose can effectively replace up to 50% lactose in starter diets.

• 한국수산과학회지
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• 제14권4호
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• pp.269-275
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• 1981

연근해 어업용 낚시 6가지형에 대하여 만능실험기로 인장속도를 290mm/min와 780mm/min로 하여 실험한 결과는 다음과 같다. 1) 낚시의 직경은 d, 미늘 기부에서 허리굽이까지의 거리를 w라 하면 낚시의 파단하중은 $B={\alpha}\;wd^2+\beta$ (단, B는 kg, w와 d는 mm)로 나타내며, 인장연도가 290mm/min 일 때의 $\alpha,\;\beta$는 둥근형 낚시 $SR_{p}-F_{1}B,\;SR_{p}-F_{1}S$는 $\alpha_{s}=0.5,\;\beta_{s}=1.6$, 모난형 낚시 $SA_{a}-F_{1}S,\;SA_{a}-F_{1}S_k,\;LA_{a}-F_{1}S_{k}$는 $\alpha_{s}=1.1,\;\beta_{s}=2.0$긴 낚시 $LA_{p}-F_{1}S$는 $\alpha_{s}=0.4,\;\beta_{s}=1.5$정도이다. 2) 인장속도가 780mm/min 일 때 윗식에서 $\alpha,\;\beta$는 둥근형 낚시는 $\alpha_{f}=0.4,\;\beta_{f}=1.4$모난형 낚시는 $\alpha_{f}=1.0$ 일본산은 $\beta_{f}=0.9$, 국산은 $\beta_{f}=-2.5$ 긴 낚시는 $\alpha_{=}0.6,\;\beta_{f}=0.4$ 정도이다. 3) 낚시의 파단변형률은 $40\sim60\%$ 정도이며, 인장속도가 빠를 때의 변형률은 느릴 때에의 $95\%$ 정도이나, 빠를 때의 파단하중은 느릴 때의 $80\%$ 정도이다. 4) 낚시가 파단되는 부위는 인장속도에 관계없이 거의 모두 허리굽이 부분이며 꼭지 기부에서 파단점까지의 거리는 낚시 길이와 거의 같다.