• 한국세라믹학회지
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• 제44권11호
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• pp.627-632
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• 2007

We have studied the ac conductivity of insulating $La_{0.7}Sr_{0.3}FeO_3$ in the frequency range 20 Hz-l MHz and in the temperature range 80-300 K. We have analyzed experimental results in the frame works of the quantum-mechanical tunneling mechanism (QMT) and the hopping of barrier mechanism (HOB). We observed that small polaron QMT model is the most suitable mechanism for the low temperature ac conductivity of $La_{0.7}Sr_{0.3}FeO_3$.

• 한국산학기술학회논문지
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• 제13권2호
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• pp.471-477
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• 2012

SCM420재질의 기어를 담금질을 실시한 후 초경호브(Hob)에 PACVD 코팅처리 후 표면경도가 높은 표면(HRC 60)을 절삭하였다. 코팅처리 없이 난삭재(難削材)로 분류되는 경도가 큰것, 경한 물질을 포함한 것, 강도가 높은 것에 공구수명과 생산성을 향상에는 한계성을 가지고 있다. 이를 개선하기 위해 초경호브에 TiCN코팅처리 전후에 대하여 Skiving 절삭으로 코팅처리 한 호브가 가공성이 좋고, 공구마멸이 적어, 공구수명이 2.5배 증가하는 결과를 얻었다. 실험은 CNC 스카이빙 호빙머신을 이용하여 습식절삭으로 절삭속도와 이송량으로 다양한 조건을 적용하여 공구마멸과 표면거칠기 데이터를 얻었다. 실험결과 조건 2에서(V=200m/min F=0.7mm/rev) Cutting speed가 절삭표면에 Feed Mark가 미세하고, 표면거칠기는 Rmax $4.7{\mu}m$(Ra $1.19{\mu}m$)의 데이터를 얻었다.

• 대한기계학회논문집
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• 제19권3호
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• pp.877-885
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• 1995

Cold forging die for metal scissor is made by electric discharge machine. The impression of female die is made by electric discharge machine, the heat treatment is applied, and the impression is polished. When we forge goods by using this kind of die, the abrasion is severe and the crack occurs after forging about 240 strokes. Because the die should be frequently produced in the case, the cost rises, the work is delayed, and the precesion of goods is not good. Therefore, the electric discharge machine was not used in this study. Main die was produced by making hob, installing the hob to cold hobbing press, indenting the die material, and cold hobbing the impression. The die life was increased to 5,000-6,000 strokes in this case. In the future study, the die life will be increased to 10,000 strokes by changing the following : (1) the pre-treatment of slug, (2) the structure of die block, (3) the heat treatment of die material

• 한국군사과학기술학회지
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• 제20권4호
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• pp.497-504
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• 2017

This paper proposes a method to measure the airburst height by utilizing a high speed camera. This method might be applied to the test of which flight target is alive after the burst. The proposed method consists of four main steps. The first step is to compute the impact point using the sea surface height. The second step is to compute the height of burst (HOB) by using the distance from the camera to the impact point. This could be different from the real explosion height. That is because the distance from the camera to the burst point is not the same as it from the camera to the impact point. Therefore, the third step is to calculate the approach angle of the flight target with respect to the installed camera. Then, the last step is to compensate the computed height by using the approach angle. The result of the proposed method is compared with it from the triangulation. In this paper, the HOB error is also analyzed regarding the approach angle difference. Based on this analysis, the camera position might be suggested for error reduction.

• 여성건강간호학회지
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• 제8권2호
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• pp.244-256
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• 2002

The purpose of this study was to examine the effects on labor pain and duration of delivery time for primipara women treated by San-Yin-Jiao(SP-6) and Hob-Gog(LI-4) acupressure. The design of this study was a nonequivalent control group non-synchronizedpost test only design. It was done to identify the effects of SP-6 acupressure or LI-4 acupressure on labor pain in primipara women. The benefits of using SP-6 acupressure or LI-4 acupressure were evaluated by comparing three groups, a SP-6 acupressure group, a LI-4 acupressure group and a control group, not treated with acupressure. The participants included 192 primiparas who underwent vaginal delivery, 72 primiparas in the control group, 71 in the SP-6 acupressure group and 49 in the LI-4 acupressure group. Data were collected using a structured questionnaire consisting of general characteristics, a subjective labor pain scale (Johnson, 1974), and measurement of duration of delivery time. The results of this study are summarized as follows : 1. Differences in the acupressure effect for SP-6 and LI-4 were analyzed using Scheffe's test which showed that differences in the control group vs the SP-6 group and the control group vs the LI-4 group were statistically significant (t=21.767, p<0.05; t=23.923, p<0.05), but the SP-6 group vs the LI-4 group showed no significant differences. 2. The duration of delivery time in the group which had SP-6 acupressure or LI-4 acupressure was shorter (400.77${\pm}$153.34; 379.10${\pm}$127.60) than in the control group (528.68${\pm}$239.08). Differences in the effects of acupressure with SP-6 and LI-4 were also analyzed by Scheffe's test. Control group vs SP-6 group and Control group vs LI-4 group were significantly different(t=127.91, p<0.05; t=149.58, p<0.05), but the SP-6 group vs the LI-4 group did not show any statistically significant difference (t=21.67). This study has shown that SP-6 and LI-4 acupressure were both effective in relation to labor pain and duration of delivery time for primiparas. But it is necessary to replicate the study with a larger number of participants to generalize of the results.

• 한국가스학회지
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• 제10권4호
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• pp.17-22
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• 2006

집단에너지와 도시가스사업은 청정에너지의 사용과 에너지효율 및 절감 측면에서 많은 장점이 있다. 공급권역 충돌로 인한 중복투자의 문제와 취사전용 천연가스 공급요구는 수익자 부담원칙의 파괴, 교차보조 등 여러 가지 문제점을 일으킨다. 위와 같은 배경 아래, 본 연구는 에너지산업의 교차보조에 관한 문제점을 분석하고, 다음과 같은 정책대안을 제시하고자 한다. 첫째, 비용과 편익효과가 정의 관계를 유지할 수 있도록 에너지비용 부담에 대한 시장구조를 개선해야 한다. 따라서 수익자부담원칙이 엄격히 준수되어야 한다. 둘째, HOB에 의한 지역난방 확대공급은 제한해야 함이 타당하다. 마지막으로 교차보조의 문제와 정책금융 지원제도가 개선될 경우에는, 시장 참여자의 수익성도 충분히 제고할 수 있는 방안을 제안한다.

• 한국항만학회지
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• 제13권1호
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• pp.41-50
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• 1999

The main purpose of this study is to design the port marketing strategies for strengthening the competitive power of container terminal. So far many attempts have been made to analyze the international competitiveness of the terminal. Six factors hypothesized by this study come from previous research analyses about customers preference for port selection. Those are Cost Centrality and Intermediacy Free trade port Inland transportation connections Political and Economic institution and Port facilities. this study analyzes the most important factors about hob port and transhipment port separately through questionnaire analysis about users(shipper shipping company and freight forwarder) influencing on port selection. The results of this study were found as follows:

• 한국컴퓨터정보학회논문지
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• 제22권9호
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• pp.81-89
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• 2017

The CRP(Container Relocation Problem) algorithms pursuing efficient container relocation of wharf container terminal can not be deterministic because of the large number of layout cases. Therefore, the CRP algorithms should adopt trial and error intuition and experimental heuristic techniques. And because the heuristic can not be best for all individual cases, it is necessary to find metrics which show excellent on average. In this study, we analyze GLAH(Greedy Look-ahead Heuristic) algorithm which is one of the recent researches in detail, and propose a heuristic metrics HOB(sum of the height differences between a badly placed container and the containers prohibited by the badly placed container) to improve the algorithm. The experimental results show that the improved algorithm, GLAH', exerts a stable performance increment of up to 3.8% in our test data, and as the layout size grows, the performance increment gap increases.

• Journal of Advanced Marine Engineering and Technology
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• 제26권3호
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• pp.337-343
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• 2002

This study deals with evaluation of bending fatigue strength in shaving gears. The saying gears were manufactured by processes that are currently used in most gears manufacturing companies. The test gears are bobbed, then the tooth surface are treated by a combination of shaving, carburizing and shot peening. The constant stress amplitude fatigue test is performed by using an electro-hydraulic servo-controlled pulsating tester. The S-N curves are obtained and illustrated. In this study, the effect of shaving process and shot peening was investigated and evaluated quantitatively on the fatigue strength. The enhancement of fatigue strength due to shaving process and shot peening is clarified.

• 동아시아식생활학회지
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• 제9권4호
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• pp.409-420
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• 1999

$\ulcorner$GANPYUN CHOSUN YORI-JEBUP$\lrcorner$,a book of cooking was written in Korean in 1934. The kinds of food were analyzed of cooking method, materials, measuring unit of materials by this book. Findings from this book are summarized as follows: 1. There were 8 kinds of Bap and 18 kinds of Zook. 2. There were 31 kinds of Korean Soup. 10 kinds of Ziggae, 4 kinds of Jun-gol. 3. There were Side-dishes including 6 kinds of Jim, 5 kinds of Jijimee, 7 kinds of Sanjuk, 9 kinds of Junyua. 18 kinds of Na-mool, 4 kinds of Moo-chim, 3 kinds of Ho, and 15 kinds of Po and were 8 kinds of dry side-dish. 4. Utensil to be used che(sieve), sot(pot). nambi(pan), Sugarak(spoon), and yang peon(bowl). 5. The measuring units were various. for example mal, dei, hob, etc. 6. The processing of cooking included preparation and boiling process. The processing of preparation were puting. mixing, and being cold, and the processing of heating were steaming and boiling.