• Title/Summary/Keyword: HOTSPOT

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Research on the Applicability of Target-detection Methods for Land-based Hyperspectral Imaging

  • Qianghui Wang;Bing Zhou;Wenshen Hua;Jiaju Ying;Xun Liu;Lei Deng
    • Current Optics and Photonics
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    • v.8 no.3
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    • pp.282-299
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    • 2024
  • Target detection (TD) is a research hotspot in the field of hyperspectral imaging (HSI). Traditional TD methods often mine targets from HSIs under a single imaging condition, without considering the influence of imaging conditions. In fact, the spectra of ground objects in HSIs are uncertain and affected by the imaging conditions (weather, atmospheric, light, time, and other angle conditions including zenith angle). Hyperspectral data changes under different imaging conditions. Therefore, the detection result for a single imaging condition cannot accurately reflect the effectiveness of the detection method used. It is necessary to analyze the performance of various detection methods under different imaging conditions, to find a more applicable detection method. In this paper, we study the performance of TD methods under various land-based imaging conditions. We first summarize classical TD methods and evaluation methods. Then, the detection effects under various imaging conditions are analyzed. Finally, the concepts of the stability coefficient (SC) and effective area under the curve (EAUC) are proposed to comprehensively evaluate the applicability of detection methods under land-based imaging conditions, in terms of both detection accuracy and stability. This is conducive to our selection of detection methods with better applicability in land-based contexts, to improve detection accuracy and stability.

Estimating carbon dioxide uptake in wetland ecosystems of Tumen River Basin using eddy covariance flux data (에디 공분산 기반의 플럭스 타워 관측자료를 이용한 두만강 유역 습지 생태계 CO2 흡수량 분석)

  • Chen, Pengshen;Zhao, Shuqing;Cui, Guishan;Lee, Dongkun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.27 no.3
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    • pp.67-74
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    • 2024
  • In the context of rapid temperature rise in mid-to-high latitude regions, cold region wetlands have become a hotspot for current wetland carbon cycle research due to their high sensitivity to climate change. Strengthening the monitoring of CO2 fluxes in wetland ecosystems is of great practical significance for clarifying the carbon balance of wetlands and maintaining the ecological balance of wetland ecosystems in China's high latitude regions. In this study, the carbon flux (NEE, Net ecosystem exchange; GPP, Gross Primary Production; RECO, Ecosystem response) of Jingxin Wetland was monitored by eddy correlation method from August 2021 to March 2024.2022-2023 shows CO2 sinks, absorbing 349.4 g C·m-2·yr-1 annually. The correlation analysis showed that Ta, VPD and PPFD were the main environmental factors affecting CO2 flux in Jingxin wetland.

Mitochondrial Genome Microsatellite Instability and Copy Number Alteration in Lung Carcinomas

  • Dai, Ji-Gang;Zhang, Zai-Yong;Liu, Quan-Xing;Min, Jia-Xin
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.4
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    • pp.2393-2399
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    • 2013
  • Objective: Mitochondrial DNA (mtDNA) is considered a hotspot of mutations in various tumors. However, the relationship between microsatellite instability (MSI) and mtDNA copy number alterations in lung cancer has yet to be fully clarifieds. In the current study, we investigated the copy number and MSI of mitochondrial genome in lung carcinomas, as well as their significance for cancer development. Methods: The copy number and MSI of mtDNA in 37 matched lung carcinoma/adjacent histological normal lung tissue samples were examined by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) assays for sequence variation, followed by sequence analysis and fluorogenic 5'-nuclease real-time PCR. Student's t test and linear regression analyses were employed to analyze the association between mtDNA copy number alterations and mitochondrial MSI (mtMSI). Results: The mean copy number of mtDNA in lung carcinoma tissue samples was significantly lower than that of the adjacent histologically normal lung tissue samples (p<0.001). mtMSI was detected in 32.4% (12/37) of lung carcinoma samples. The average copy number of mtDNA in lung carcinoma samples containing mtMSI was significantly lower than that in the other lung carcinoma samples (P<0.05). Conclusions: Results suggest that mtMSI may be an early and important event in the progression of lung carcinogenesis, particularly in association with variation in mtDNA copy number.

Korea Road-Kill Observation System: The First Case to Integrate Road-Kill Data in National Scale by Government

  • Kim, Kyungmin;Woo, Dong-Gul;Seo, Hyunjin;Park, Taejin;Song, Eui-Geun;Choi, Tae-Young
    • Journal of Forest and Environmental Science
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    • v.35 no.4
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    • pp.281-284
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    • 2019
  • Efficient management of road-kill data is difficult at national scale when there are many organizations that are in charge of different road types. Here, we described the first case to integrate road-kill data through Korea Road-kill Observation System (KROS) by the Korean government. The system was launched in June 2018 to approximately 3,000 road menders. During 15 months, 5,812 road-kill observations were registered on KROS including mammals, birds, reptiles and amphibians. Of them, about 86 % was occupied by five species (Hydropotes inermis, Felis catus, Capreolus pygargus, Nyctereutes procyonoides, and Canis lupus familiaris) listed in number of occurrences. The observed road-kill frequency rapidly increased until April 2019 and peaked on May 2019. However, as the system is just starting, the results from KROS cannot be treated as the exact representation of road-kill trend in the country. Although the efficient method to manage national road-kill statistic is arranged, still there are some limitations to overcome to make the system stable.

Diversity of the genus Sheathia (Batrachospermales, Rhodophyta) in northeast India and east Nepal

  • Necchi, Orlando Jr.;West, John A.;Ganesan, E.K.;Yasmin, Farishta;Rai, Shiva Kumar;Rossignolo, Natalia L.
    • ALGAE
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    • v.34 no.4
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    • pp.277-288
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    • 2019
  • Freshwater red algae of the order Batrachospermales are poorly studied in India and Nepal, especially on a molecular basis. During a survey in northeast India and east Nepal, six populations of the genus Sheathia were found and analyzed using molecular and morphological evidence. Phylogenetic analyses based on the rbcL gene sequences grouped all populations in a large clade including our S. arcuata specimens and others from several regions. Sheathia arcuata represents a species complex with a high sequence divergence and several smaller clades. Samples from India and Nepal were grouped in three distinct clades with high support and representing new cryptic species: a clade formed by two samples from India, which was named Sheathia assamica sp. nov.; one sample from India and one from Nepal formed another clade, named Sheathia indonepalensis sp. nov.; two samples from Nepal grouped with sequences from Hawaii and Indonesia (only 'Chantransia' stages) and gametophytes from Taiwan, named Sheathia dispersa sp. nov. Morphological characters of the specimens from these three species overlap one another and with the general circumscription of S. arcuata, which lacks the heterocortication (presence of bulbous cells in the cortical filaments) present in other species of the genus Sheathia. Although the region sampled is relatively restricted, the genetic diversity among specimens of these three groups was high and not closely related in the phylogenetic relationship with the other clades of S. arcuata. These data corroborate information from other groups of organisms (e.g., land and aquatic plants) that indicates this region (Eastern Himalaya) as a hotspot of biodiversity.

The Effects of Repetitive Transcranial Magnetic Stimulation on Balance Ability in Acute Stroke Patients

  • Ji, Sang-Goo;Shin, Young-Jun;Kim, Myoung-Kwon
    • Journal of the Korean Society of Physical Medicine
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    • v.11 no.3
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    • pp.11-17
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    • 2016
  • PURPOSE: The aim of the present study was to determine whether high frequency repetitive transcranial magnetic stimulation (rTMS) can improve balance ability in acute stage stroke patients. METHODS: The study was conducted on 30 subjects diagnosed with hemiparesis caused by stroke. The experimental group consisted of 15 patients that underwent rTMS for 15 mins and the control group consisted of 15 patients that underwent sham rTMS (for 15 minutes). A 70-mm figure 8 coil and a Magstim Rapid stimulator was used in both groups. Patients in the experimental group received 10 Hz rTMS applied to the hotspot in the lesioned hemisphere in 10-second trains with 50-second intervals between trains, for 15 minutes (total 2,000 pulses). Both groups received conventional physical therapy for 30 minutes a day, 5 days a week, for 4 weeks. Static balance ability analysis was performed using the Gaitview system to measure pressure rate, postural sway, and total pressure, and dynamic balance ability analysis was performed to measure pressure variables using a balance system. RESULTS: A significant difference was observed in post-training gains for pressure rate, total pressure in static balance, and overall stability index in dynamic balance between the experimental group and the control group (p<.05). CONCLUSION: The results of this study indicate that high frequency rTMS may be beneficial for improving static and dynamic balance recovery in acute stroke patients.

Proposal of Traffic Management Strategy between Hierarchical Mobile-WiMAX/WLAN Networks (계층적 Mobile-WiMAX/WLAN 네트워크에서의 트래픽 관리 전략에 관한 연구연구)

  • Moon, Tae-Wook;Kim, Moon;Cho, Sung-Jun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.1
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    • pp.153-160
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    • 2009
  • A hierarchical network between Mobile-WiMAX and WLAN systems is to make it possible to utilize wireless internet services including time sensitive applications such as VoIP, VOD, visual telephony etc. During the process of vertical handoff decision from Mobile-WiMAX to WLAN hotspot, vertical handoff delay causes user dissatisfaction because it doesn't provide the seamless wireless internet service. We make use of type of service (ToS) parameters in IEEE 802.16e specification as the criterion parameter of vertical handoff decision process in hierarchical Mobile-WiMAX/WLAN networks. In this paper, we propose the process of vertical handoff decision for seamless wireless internet service which is sensitive to time delay. If type of service is time sensitive application, the decision of vertical handoff is withdrawn until the service is terminated. In focus on user satisfaction, if the proposed traffic management strategy in hierarchical Mobile-WiMAX/WLAN networks is used, user will utilize seamless wireless internet services including time sensitive applications.

A Selection of High Pedestrian Accident Zones Using Traffic Accident Data and GIS: A Case Study of Seoul (교통사고 데이터와 GIS를 이용한 보행자사고 개선구역 선정 : 서울시를 대상으로)

  • Yang, Jong Hyeon;Kim, Jung Ok;Yu, Kiyun
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.34 no.3
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    • pp.221-230
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    • 2016
  • To establish objective criteria for high pedestrian accident zones, we combined Getis-ord Gi* and Kernel Density Estimation to select high pedestrian accident zones for 54,208 pedestrian accidents in Seoul from 2009 to 2013. By applying Getis-ord Gi* and considering spatial patterns where pedestrian accident hot spots were clustered, this study identified high pedestrian accident zones. The research examined the microscopic distribution of accidents in high pedestrian accident zones, identified the critical hot spots through Kernel Density Estimation, and analyzed the inner distribution of hot spots by identifying the areas with high density levels.

Single Image Dehazing Using Dark Channel Prior and Minimal Atmospheric Veil

  • Zhou, Xiao;Wang, Chengyou;Wang, Liping;Wang, Nan;Fu, Qiming
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.1
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    • pp.341-363
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    • 2016
  • Haze or fog is a common natural phenomenon. In foggy weather, the captured pictures are difficult to be applied to computer vision system, such as road traffic detection, target tracking, etc. Therefore, the image dehazing technique has become a hotspot in the field of image processing. This paper presents an overview of the existing achievements on the image dehazing technique. The intent of this paper is not to review all the relevant works that have appeared in the literature, but rather to focus on two main works, that is, image dehazing scheme based on atmospheric veil and image dehazing scheme based on dark channel prior. After the overview and a comparative study, we propose an improved image dehazing method, which is based on two image dehazing schemes mentioned above. Our image dehazing method can obtain the fog-free images by proposing a more desirable atmospheric veil and estimating atmospheric light more accurately. In addition, we adjust the transmission of the sky regions and conduct tone mapping for the obtained images. Compared with other state of the art algorithms, experiment results show that images recovered by our algorithm are clearer and more natural, especially at distant scene and places where scene depth jumps abruptly.

Extraction of Crime Vulnerable Areas Using Crime Statistics and Spatial Big Data (공간 빅데이터와 범죄통계자료를 이용한 범죄취약지 추출)

  • Park, So-Rang;Park, Jae-Kook
    • Journal of Convergence for Information Technology
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    • v.8 no.1
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    • pp.161-171
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    • 2018
  • This study set out to identify crime vulnerable areas with the GIS spatial analysis technique for the prediction of crimes. Crime vulnerable areas were extracted from the statistics of crimes with the GIS hotspot analysis technique and the inverse distance weighted(IDW) method applied to different crimes according to places and use districts. The scope of surveillance and weight were calculated for each of CPTED surveillance elements including CCTV, streetlamp, patrol division, and police substation. Maps of crime vulnerable areas were overlapped one after another to make a CPTED-based one expressed in four grades(safety, attention, warning, and risk).