• 대한원격탐사학회지
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• 제37권5_1호
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• pp.917-926
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• 2021

벼 쓰러짐은 벼농사의 대표적인 기상재해 피해로써 강한 바람과 강우로 발생한다. 원격탐사 기법은 넓은 지역의 벼 쓰러짐을 효과적으로 탐지하기에 적절한 방법이다. 실제로 벼 쓰러짐은 벼 키가 최대인 생육 시기에 주로 발생하여 군락의 큰 구조적 변화를 불러오기 때문에 분광 반사도 차이를 야기한다. 따라서, 본고에서는 나주에 위치한 전남농업기술원의 2020년 태풍에 의한 논벼 피해를 444 nm부터 842 nm까지 10개 밴드로 구성된 카메라 영상으로 분석하였다. 드론 영상마다 벼 쓰러짐 피해를 받은 영역과 벼 쓰러짐 피해가 없는 영역으로 구분하여 벼 쓰러짐 영역의 분광 반사도 특성 차이와 식생 탐지에 주로 사용되는 식생지수인 NDVI(Normalized Difference Vegetation Index), NDRE (Normalized Difference Red Edge), CCI (Chlorophyll Carotenoid Index)의 변화를 살펴보았다. 반사도 값의 변화는 밴드6(668 nm)에서 가장 적었으며, 이를 중심으로 밴드 파장이 감소와 증가할수록 일반 논벼 보다 쓰러짐 영역 반사도가 커졌다. 또한, 쓰러진 벼를 묶어 세운 복구 지역은 대부분의 밴드에 걸쳐 반사도가 크게 감소함을 볼 수 있었다. NDVI와 NDRE는 벼 쓰러짐 영역에 대해 민감하게 반응하였으나, 그 반응 대상 및 정도는 서로 달랐다. 본 연구의 결과는 향후 드론과 위성을 이용한 벼 쓰러짐 피해 조사 알고리즘에 기여될 것으로 기대한다.

• International Journal of Computer Science & Network Security
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• 제23권4호
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• pp.55-68
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• 2023

In recent years, the Television White Space (TVWS) has attracted the interest of many researchers due to its propagation characteristics obtainable between 470MHz and 790MHz spectrum bands. The plenty of unused channels in the TV spectrum allows the secondary users (SUs) to use the channels for broadband services especially in rural areas. However, when the number of SUs increases in the TVWS wireless network the aggregate interference also increases. Aggregate interferences are the combined harmful interferences that can include both co-channel and adjacent interferences. The aggregate interference on the side of Primary Users (PUs) has been extensively scrutinized. Therefore, resource allocation (power and spectrum) is crucial when designing the TVWS network to avoid interferences from Secondary Users (SUs) to PUs and among SUs themselves. This paper proposes a model to improve the resource allocation for reducing the aggregate interface among SUs for broadband services in rural areas. The proposed model uses joint power and spectrum hybrid Firefly algorithm (FA), Genetic algorithm (GA), and Particle Swarm Optimization algorithm (PSO) which is considered the Co-channel interference (CCI) and Adjacent Channel Interference (ACI). The algorithm is integrated with the admission control algorithm so that; there is a possibility to remove some of the SUs in the TVWS network whenever the SINR threshold for SUs and PU are not met. We considered the infeasible system whereby all SUs and PU may not be supported simultaneously. Therefore, we proposed a joint spectrum and power allocation with an admission control algorithm whose better complexity and performance than the ones which have been proposed in the existing algorithms in the literature. The performance of the proposed algorithm is compared using the metrics such as sum throughput, PU SINR, algorithm running time and SU SINR less than threshold and the results show that the PSOFAGA with ELGR admission control algorithm has best performance compared to GA, PSO, FA, and FAGAPSO algorithms.

• 한국임상수의학회지
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• 제14권2호
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• pp.308-318
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• 1997

The present experiment was performed in order to know the treatment effect of aquapuncture with hepatonics on recovery in artificially induced hepatic damaged dogs by carbon tetrachloride. The animals were divided into a control and two experimental groups (aquapuncture with taurine into Gan-su acupoint: Aa-I group and aquapuncture with taurine into blank acupoint in the thigh: Aa-II group). The changes of serum enzyme activities (ALT, AST and ALP), serum total protein contents, protein fractions and pathohistological findings of the liver were examined after application of aquapunctiuf treauent The results obtained through this experiment were summarized as follows : The serum ALT activities tendeded to decrease in experimental group compared with those of control group. Significances were detected at 5th (p<0.05) and 7th (p<0.05) day in Aa-I group and 7th day (p<0.05) in Aa-II group, respectively. Low value was fecund in Aa-I group compared with Aa-II groups but significance was not observed between two experimental groups. The serum AST activities in experimental group showed decreasing tendency compared with those of control group. Significances were observed at 2nd (p<0.05) and 5th (p<0.05) day in Aa-I group and 2nd (p<0.05) day in Aa-II groups respectively. Aa-I group showed lower values than those of Aa-II groups however, no significance was detected between experimental groups. The serum ALP activities of experimental group showed a slight decrease compared with those of control group, however, significance was not detected among all groups. The serum total protein content in experimental group showed tendency of increase compared with control group. Significance was found at 2nd day (p<0.05) in Aa-I group, but there was no significance in Aa-II group. Further significant increase of total protein content was seen at 1st day (p<0.05) in Aa-I group compared with Aa-II group. The change of serum albumin content in experimental group showed tendency of increase compared with control. Significant increases were detected at 1st (p<0.01) and 2nd (p<0.01) day in Aa-I group, respectively. Aa-II group showed increase compared with control groups but significance was not observed. Further significant increase was at 1st day (p <0.05) in Aa-I group compared with Aa-II group. The change of ${\beta} $-globulin in Aa-I group was slightly decreased compared with control group. Aa-II group was similar to controls but significance was not observed among all groups. The change of P-globulin content in Aa-I group showed tendency of increase compared with control and Aa-II group showed the tendency of decrease compared with control. The change of ${\gamma}$-globulin content experimental group showed tendency of increase compared with control, however, significance was not detected among groups. The change of A/G ratio in Aa-I group showed tendency of increase compared with control group and Aa-II group was similar to controls but no significance was found among groups. As for pathohistological observations the grade of hepatocellular vacuolized degeneration and necrosis in Aa-I group was milder than those of control and Aa-II groups and the change of Aa-II group was similar to that of control. Considering above finding collectively, it was thought that aquapuncture of Gan-su acupoint with hepatonics was more effective than aquapuncture of blank acupoint for the recovery of hepatic damage.

• 대한원격탐사학회지
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• 제37권6_1호
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• pp.1559-1572
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• 2021

다중분광카메라의 기술 개발로 인해 구조적 특성뿐만 아니라 생화학적, 생리적 특성을 가지는 식생지수를 다양한 공간 규모에서 활용할 수 있게 되었다. 이에 본 연구는 스트레스를 받은 노지작물을 대상으로 지상 초분광계 및 무인기 영상 기반 구조적, 생화학적, 생리적 계열의 식생지수 반응을 평가하였다. 마늘을 대상으로 서로 다른 생육시기에 고농도의 제초제를 살포하여 약해 처리하였으며, 정상 생육에 비해 지상부 건물중이 46.9~84.5% 감소하는 등 큰 피해가 나타났다. 제초제를 살포한 처리구에서 근적외선 분광반사도 값은 꾸준하게 감소하였으며, 구조적 식생지수에서 작물의 약해 피해가 명확하게 표현되었다. 생화학적 식생지수의 경우 일부 지수를 제외하고는 작물의 피해 상태를 표현하였으나 생리적 식생지수는 잎이 고사하고 드러나는 멀칭비닐의 영향으로 약해 피해를 해석하기에 어려움이 있었다. 제초제 살포 후 서로 다른 공간 규모에서 관측된 식생지수의 감소율 차이는 구조적 식생지수의 경우 평균적으로 2.3%로 나타났으며, 정규화 식생지수의 경우 1.3~4.1%의 분포를 보였다. 비록 생리적 식생지수가 작물 스트레스에 민감하다고 알려졌지만, 노지작물의 경우 작물 스트레스 종류와 재배 환경에 따라 적합한 식생지수를 활용하여야 한다는 것, 공간 규모에 따른 오차를 최소화하기 위해서는 정규화 식생지수를 활용해야 한다는 것을 확인하였다.