• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.5
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• pp.1186-1192
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• 1990

It is well known that the fatigue crack growth retardation following overloads can be estimated reasonably well by the models of Wheeler and Willenborg. These models, however, can not explain the delayed-retardation revealed by every experimental result. This means that they necessarily have some qualitative defects in themselves despite of a fair approximation of quantity. In fact, they did not take into account the effects of the compressive portion of the overload cycle such as the change of reversed plastic zone size. The present study is focused on the acceleration effect in the reversed plastic zone in order to analyze qualitatively delayed-retardation phenomenon following single peak overload on the fatigue crack growth behavior using 2024-T3 aluminum alloy.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.23 no.1
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• pp.5-13
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• 1978

An experiment was carried out to find out effective heading date and period of limited ripening in different regions of climatic conditions by sowing date and length of nursery stage of a new variety Milyang 23. Since varieties of Tongil line have a character of premature heading, these do not show the symptom of senescent even though length of nursey stage was delayed. And the delay of heading date is due to late transplanting date, on the other hand, length of nursery stage delayed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.3
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• pp.198-205
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• 1982

In 1980, rice was considerably damaged by abnormal low temperature. In this paper, to determine the effect of low temperature on the growth and nutrition of rice, the experiment were carried out: varietal response to low temperature in the region with different elevations. Regional differences of heading response to low temperature were observed among varieties. The difference of days between regions were bigger in tongil lines than Japonica lines. Especially, Milyang 42 and Hangangchalbeo might belong the cold suceptible group, since the varieties were severely delayed their heading in the high mountainous region as comparred to plain region. The delay of heading with low temperature was brought out grain sterility, and fertility and ripening ratio is influenced cold tolerance and elevations, and it's decreased yield. Varieties with higher grain sterility by low temperature have higher total nitrogen content, but tended to have lower potassium and phosphate contents in the flag leaf. High content of total nitrogen, low contents of potassium and silicate were observed in the sterilized grain chaff an the opposite result were noted in the ferilized grain chaff at the ripening stage. The results reveal that the balance of these mineral element may play an important role in ripening and possibly cold tolerance.

• 월간 기계설비
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• s.310
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• pp.106-107
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• 2016

공정거래위원회의 불공정 하도급거래 제재 무게 중심이 대금 지연이자 수수료 미지급, 부당특약 설정 등에서 추가공사, 설계변경에 따른 대금 지급 여부로 확대되고 있다. 공사물량이 추가 변경됐는데도 수급사업자에 변경 계약서를 발급하지 않고 대금을 제대로 주지 않는 행위들이 여전히 제재 사각지대에 놓여 있다는 판단에서다.

• Geophysics and Geophysical Exploration
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• v.13 no.3
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• pp.277-285
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• 2010

For regional earthquakes in the Korean Peninsula, the seismic Lg waves have the largest amplitude. Our researches in South Korea found that more reasonable low ${Q_{Lg}}^{-1}$ was obtained as the inter-station distances increase. The other methods such as coda normalization method and multiple lapse time window method also produced that the low ${Q_{Lg}}^{-1}$ is related to the values of seismically inactive region.

• The Journal of Bigdata
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• v.8 no.1
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• pp.73-82
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• 2023

Marine debris not only affects the survival of marine life, water pollution, and scenery but also has secondary effects on economic loss and human health. While research on underwater and surface debris is actively ongoing, solutions to marine debris in hard-to-reach blind spots are being developed slowly. To address this problem, we utilize drones to detect and track marine debris in blind spots such as tetrapods. The detected debris is then visualized by calculating its location coordinates using the drone's GPS, altitude, and heading values. The proposed method of using drones for detecting marine debris and matching it with longitude and latitude coordinates provides an effective solution to the problem of marine debris in blind spots.

• Journal of the Korea Society of Computer and Information
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• v.14 no.10
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• pp.1-10
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• 2009

Precise branch predictor has a profound impact on system performance in modern processor architectures. Recent works show that prediction latency as well as prediction accuracy has a critical impact on overall system performance as well. However, prediction latency tends to be overlooked. In this paper, we propose Branch Pre-Prediction policy to tolerate branch prediction latency. The proposed solution allows that branch predictor can proceed its prediction without any information from the fetch engine, separating the prediction engine from fetch stage. In addition, we propose newly modified BTE structure to support our solution. The simulation result shows that proposed solution can hide most prediction latency with still providing the same level of prediction accuracy. Furthermore, the proposed solution shows even better performance than the ideal case, that is the predictor which always takes a single cycle prediction latency. In our experiments, IPC improvement is up to 11.92% and 5.15% in average, compared to conventional predictor system.

• The Optical Journal
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• s.109
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• pp.28-34
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• 2007

90년대 중반 국내 시장에 본격 보급된 이래, 폭발적인 인기를 모으며 연평균 20% 이상의 상승곡선을 그리던 디지털카메라가 올해를 기점으로 점차 주춤할 전망이다. 현재 국내 디지털카메라 시장은 220-230만대 내외로 추정되는 가운데 기존 콤팩트 디카 시장의 포화현상으로 인해 신규시장을 형성하려는 카메라 업체들간의 전략과 새롭고 다양한 기능의 카메라에 대한 사용자층의 기대확산 등이 맞물리면서 그 어느 때보다 복잡하고 다양한 시장 기류가 형성 될 것으로 보인다. 특히 디카 성능의 표준화에 따라 업체들은 소비자의 다양한 구매심리를 끌어내기 위해 자신만의 특징적인 제품개발에 집중하는가 하면 그동안 사각지대로 불렸던 여성 소비자를 겨냥하여 소형.경량화된 DSLR마케팅에 집중하는 등 경쟁이 치열할 것으로 보인다.

• Journal of Dental Rehabilitation and Applied Science
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• v.27 no.4
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• pp.371-392
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• 2011

The purpose of this study was to comparatively analyze the stress distribution according to the inclinations of abutments and angulations of the implant fixtures under occlusal loading force. Three study models with straight and $15^{\circ}$ and $25^{\circ}$-angled abutments were prepared following the insertion of Implants parallel to the long axis of the tooth. Additional two experimental models were fabricated with $15^{\circ}$ and $25^{\circ}$ fixture inclinations. Using ANSYS 11, a finite element analysis program, the magnitudes of stress distribution were analyzed. The magnitude of stress under loading was lowest when the load was applied vertically onto the axis of implant. And the magnitude of stress under compound(vertical+oblique) loading was increased as the inclination of implant abutment and fixture was increase. But, the distribution of stress was different as the loading conditions, because of the horizontal offset. As the offset between the axis of loading and the central axis of the implant increased, the stress was increased.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.22 no.6
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• pp.1-6
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• 2022

In this research, we suggest a real-time tele-driving system for unmanned fire truck control using the LTE communication system. The operator located in the safe area could drive the unmaned fire truck by implementing the secure tele-operation in case of the emergencies and disaster situation. A prototype of the unmaned fire truck was developed with a fire canon, a high pressure pump, a ball valve and a horse reel. The effect of time delay and FPS was quantified depending on the image sizes and the effective system for realtime tele-operation was suggested. To verify the suggested system, the test was performed between an operator and an unmanned fire truck which is approximately 30km apart. In this research, the immersion tele-driving system is suggested for real-time fire suppression with a 120ms time delay using LTE communication.