• 한국작물학회지
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• 제44권1호
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• pp.38-43
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• 1999

Over 2,000 ha of rice fields in the western and southern coastal region of Korea were flooded with sea water during the spring tide, on August 19-21, 1997, and the rice plant at heading stage was injured. The field surveys were undertaken at the sea water flooded paddy fields in Chonbuk Province, to identify the injury symptoms and rice yield damage subjected to different flooding condition and desalinization methods. Five days after sea water flooding at heading stage, the flag leaves of rice plants flooded with 30 ㎝ deep sea water withered from the tip, the withering progressed to the lower leaves in deeper flooding. The spikelets were spotted black and discolored from the tip at 50 ㎝ deep flooded rice, and some panicles changed to white at 80 ㎝ deep flooded rice. Most of the rice leaves submerged completely for an hour were withered and most of panicles changed to white. The milled rice yield, percentage of ripened grain, and 1000 grain weight of flooded rice decreased with deeper flooding water, higher water salinity and longer flooding time. Even under the same flooding conditions, the damage of rice yield varied with the growth stage: heading stage>dough stage>booting stage. Rice yield damage was less in the fields on the upper riverside than those of the fields on the estuary and seaside, because of lower water salinity. In a flooded field, the rice yield damages were reduced as the distance increased from the levees where the sea water inflowed and increased as the distance increased from the fresh water irrigation gate. The desalinization treatments consisting of frequent exchange of irrigation water and spraying with fresh water soon after flooding effectively reduced the rice yield damage.

• 센서학회지
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• 제19권1호
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• pp.62-66
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• 2010

We have proposed and demonstrated a rotation angle sensor based on the stress -optic effect of a fused fiber coupler whose transmission spectrum is altered by the torsional stress. The peak of transmission spectrum was shifted to longer wavelength region with rotation of the coupler. The rotation angle sensor revealed reproducibility and symmetric behavior with respect to the rotation direction. The sensitivity of the sensor was 0.367 [nm/degee].

• 호남수학학술지
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• 제30권1호
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• pp.75-89
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• 2008

Interrupted blood flow diminishes the concentration of oxygen in tissues. Hypoxia first appears in the region distal to the capillaries and grows throughout the entire t issue. However, the time-wise evolution of hypoxic area is diverse when some of capillaries are blocked in a multi-capillary domain with different oxygen squirt. The process of the development of hypoxia through time course is analyzed mathematically in the domain. Each source in steady state is controlled by a time sensitive function to simulate the occlusion.

• 호남수학학술지
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• 제35권1호
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• pp.37-49
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• 2013

Consider a non-degenerate open convex cone C with vertex the origin in the $n$2-dimensional Euclidean space $E^n$. We study volume properties of strictly convex hypersurfaces in the cone C. As a result, for example, if the volume of the region of an elliptic cone C cut off by the tangent hyperplane P of M at $p$ is independent of the point $p{\in}M$, then it is shown that the hypersurface M is part of an elliptic hyperboloid.

• Journal of the Optical Society of Korea
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• 제12권2호
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• pp.79-87
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• 2008

We have developed a miniature fisheye lens with $190^{\circ}$ field of view operating simultaneously in the visible and the near infrared wavelengths. The modulation transfer function characteristic for the visible wavelength is sufficient for a mega-pixel-grade image sensor. The lens also has a fair resolution in the infrared wavelength region. The calibrated $f-{\theta}$ distortion is less than 5%, and the relative illumination is over 90%. In consequence, a sharp wide-angle image can be obtained which is uniform in brightness over the entire range of field angles. The real image heights for the visible and the near infrared wavelengths have been fitted to polynomial functions of incidence angle with sub-pixel accuracies. Combined with the near equidistance projection scheme of the lens, this lens can be advantageously employed in various image-processing applications requiring a wide-angle lens.

• 센서학회지
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• 제21권2호
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• pp.151-155
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• 2012

We have investigated a refractive index sensor based on a cladded plastic optical fiber taper. The optical transmission and sensing characteristics of the device were illuminated in terms of ray optics. The sensor devices showed that the optical transmittance strongly depends on the refractive index of the external medium surrounding the tapered region.

• International Journal of Advanced Culture Technology
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• 제9권3호
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• pp.305-314
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• 2021

Currently, due to COVID-19, household waste has a lot of impact on the environment due to packaging of food delivery. In this paper, we design and implement Faster-RCNN, SSD, and YOLOv4 models for municipal waste detection and classification. The data set explores two types of plastics, which account for a large proportion of household waste, and the types of aluminum cans. To classify the plastic type and the aluminum can type, 1,083 aluminum can types and 1,003 plastic types were studied. In addition, in order to increase the accuracy, we compare and evaluate the loss value and the accuracy value for the detection of municipal waste classification using Faster-RCNN, SDD, and YoloV4 three models. As a final result of this paper, the average precision value of the SSD model is 99.99%, the average precision value of plastics is 97.65%, and the mAP value is 99.78%, which is the best result.

• 대한지리학회지
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• 제40권1호
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• pp.78-95
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• 2005

호남 장수지역 경제활동의 산업연계와 혁신네트워크에 대해 분석함으로써 지식정보화 시대의 이상적인 고령사회에 대비한 새로운 지역발전 방향을 모색하고자 하였다. 이를 위해 한국 장수지역 중의 하나인 전라북도의 순창군과 전라남도의 담양군, 곡성군, 구례군 등의 대표적 제조업체를 중심으로 심층 인터뷰를 실시하였다. 연구 결과, 산업 연계에 있어 원료구입과 노동력이용은 해당 군에서 많이 이루어지고 있고, 제조업과 농업 및 관광업간 연계와 인터넷을 이용한 통신판매가 활성화되고 있었다. 그리고 혁신네트워크에 있어서는 지식정보화시대에 가상혁신클러스터의 형성 가능성을 확인할 수 있었다. 따라서 농촌지역 발전을 위해서는 지식기반경제의 지역혁신체계 개념을 이용해 지역의 자원 및 전통지식과 밀접한 혁신네트워크 구축이 필요하다.

• 한국자원식물학회지
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• 제19권4호
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• pp.488-490
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• 2006

보리 재배면적 증가로 인하여 월동한 애멸구 밀도증가가 벼 줄무늬잎마름병의 대면적 발생 위험이 상존하고 있다. 특히 호남지역은 보리재배 논과 1모작 이앙 또는 직파재배 논이 혼재하고 있어 보리 수확과 동시에 보독충인 애멸구는 벼가 자라고 있는 논으로 대규모 이동하여 병 발생을 조장하고 있다. 재배양식에 따른 줄무늬잎마름병 발생양상은 1모작 이앙과 담수직파 재배에서 병발생이 각각 2.5, 2.4%로 이모작 이앙 1.3%보다 높았다. 보리재배 논과의 2m 이내의 거리에서 보리 수확 3일전 애멸구 밀도는 5마리에서 수확 3일후 63마리로 급격하게 증가하였다. 또한 보리재배 논과 거리가 멀어짐에 따라서 애멸구 밀도는 크게 감소하였다.

• 한국응용곤충학회지
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• 제46권1호
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• pp.165-168
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• 2007

고구마 재배지에 발생하는 풍뎅이류 유충(굼벵이)의 종류 및 종별 피해양상을 조사하였다. 고구마 재배지 토양에 발생하는 풍뎅이류는 큰검정풍뎅이(Holotrichia parallela), 참검정풍뎅이(Holotrichia diomphalia), 애풍뎅이(Anomala rufocuprea) 3종이지만 주로 발생하는 풍뎅이류는 대부분 큰검정풍뎅이로 조사되었다. 굼벵이류에 의한 고구마 괴근 피해율은 지역에 따라 차이가 있었는데 평군 2-40%였고, 심한 경우는 80% 이상의 피해를 나타낸 포장도 있었다. 큰검정풍뎅이는 10월 하순부터 다음해 6월 하순까지 토양 속에서 3령의 노령유충으로 월동하였으며, 월동기간 동안 유충의 생존율은 92%로 매우 높았다. 고구마 포장에서 큰검정풍뎅이 유충은 7월 하순부터 8월 중순 사이에 발생하기 시작하였고, 고구마의 굼벵이 피해는 8월 하순부터 나타나기 시작하여 수확기까지 지속되었다.