• Title/Summary/Keyword: DoS detection

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Iris Detection at a Distance by Non-volunteer Method (비강압적 방법에 의한 원거리에서의 홍채 탐지 기법)

  • Park, Kwon-Do;Kim, Dong-Su;Kim, Jeong-Min;Song, Young-Ju;Koh, Seok-Joo
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2018.05a
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    • pp.705-708
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    • 2018
  • Among biometrics commercialized for security, iris recognition technology has the most excellent security for the probability of the match between individuals is the lowest. Current commercialized iris recognition technology has excellent recognition ability, but this technology has a fatal drawback. Without the user's active cooperation, it cannot recognize the iris correctly. To make up for this weakness, recent trend of iris recognition development mounts a non-volunteering, unconstrained method. According to this information, the objective of this research is developing a module that can identify people iris from a video acquired by high performance infrared camera in a range of 3m and in a involuntary way. For this, we import images from the video and find people's face and eye positions from the images using Haar classifier trained through Cascade training method. finally, we crop the iris by Hough circle transform and compare it with data from the database to identify people.

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Simultaneous 22GHz Water and 44GHz Methanol Maser Survey of Ultra-compact HII Regions

  • Kim, Won-Ju;Kim, Kee-Tae;Kim, Kwang-Tae
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.1
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    • pp.83.2-83.2
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    • 2012
  • We have carried out simultaneous 22GHz $H_2O$ and 44GHz Class I $CH_3OH$ maser survey of 112 ultra-compact HII regions (UCHIIs) twice in 2010 and 2011. We detected $H_2O$ maser and $CH_3OH$ maser emission from 76(68%) and 49(44%) UCHIIs, respectively. Among them 15 $H_2O$ masers and 32 $CH_3OH$ masers are new detections. These high detection rates suggest that the occurrence periods of both masers are significantly overlapped with the UCHII phase. $CH_3OH$ masers always have small (<10 km s-1) relative velocities with respect to the natal molecular cores, while $H_2O$ masers often show larger velocities. We find 20 UCHIIs with $H_2O$ maser lines at relative velocities >30 km s-1. The formation and disappearance of $H_2O$ masers is frequent over one-year time interval. In contrast, $CH_3OH$ masers usually do not show substantial variation in intensity, velocity, or shape. The isotropic luminosities of both masers well correlate with the bolometric luminosities of the central stars when data points of lowand intermediate-mass protostars are added: $L_{H_2O}=5.89{\times}10^{-9}{(L_{bol})^{0.69}}$ and $L_{CH_3OH}=4.27{\times}10^{-9}{(L_{bol})^{0.62}}$. They also tend to increase with the 2cm radio continuum luminosity of UCHIIs and the 850 um continuum luminosity of the associated molecular cores. We discuss some individual sources.

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Detection of Anaplasma sp. in Korean Native Goats (Capra aegagrus hircus) on Jeju Island, Korea

  • Seong, Giyong;Han, Yu-Jung;Chae, Jeong-Byoung;Chae, Joon-Seok;Yu, Do-Hyeon;Lee, Young-Sung;Park, Jinho;Park, Bae-Keun;Yoo, Jae-Gyu;Choi, Kyoung-Seong
    • Parasites, Hosts and Diseases
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    • v.53 no.6
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    • pp.765-769
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    • 2015
  • Anaplasma species are obligate intracellular pathogens that can cause tick-borne diseases in mammalian hosts. To date, very few studies of their occurrence in Korean native goats (Capra aegagrus hircus) have been reported. In the present study, we investigated Anaplasma infection of Korean native goats on Jeju Island, Republic of Korea, and performed phylogenetic analysis based on the 16S rRNA gene sequences. Our results showed that Anaplasma infection was found mostly in adult female goats. The phylogenetic tree revealed that the 7 sequences identified in Korean native goats could belong to Anaplasma sp. and were distinct from A. marginale, A. centrale, and A. ovis. The results indicated that the sequences identified to belong to Anaplasma were closely related to sequences isolated from goats in China and were clustered within the same group. To our knowledge, this is the first study to detect Anaplasma sp. infection in Korean native goats.

DEM Generation of Tidal Flat by the Area Based Matching Method Using Digital Aerial Stereo Images (디지털 입체 항공사진의 영역기반매칭법에 의한 갯벌 DEM 제작)

  • Lee, Hyo-Seong;Ahn, Ki-Weon;Kim, Duk-Jin
    • Journal of the Korean Association of Geographic Information Studies
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    • v.13 no.3
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    • pp.42-52
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    • 2010
  • The purpose of this study is to produce digital elevation model (DEM) in the Jebu tidal flat, one of the west coast of the Korean Peninsula, by means of photogrammetric techniques from aerial digital stereo-images. Produced DEM would be become the fundamental data for change detection of the sediment and erosion. To do so, epipolar line is established by relative orientation. Area-based matching is then carried out based on this line and matching size according to surface property of tidal flat after a classified image is produced from reflectance and texture of the surface. As the results, DEM generated by the proposed method showed subtle changes in height more precisely than DEM using the fixed matching size and DEM by the commercial S/W in the region, such as tidal flats having few level differences.

Genetic Diversity of a Natural Population of Apple stem pitting virus Isolated from Apple in Korea

  • Yoon, Ju Yeon;Joa, Jae Ho;Choi, Kyung San;Do, Ki Seck;Lim, Han Cheol;Chung, Bong Nam
    • The Plant Pathology Journal
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    • v.30 no.2
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    • pp.195-199
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    • 2014
  • Apple stem pitting virus (ASPV), of the Foveavirus genus in the family Betaflexiviridae, is one of the most common viruses of apple and pear trees. To examine variability of the coat protein (CP) gene from ASPV, eight isolates originating from 251 apple trees, which were collected from 22 apple orchards located in intensive apple growing areas of the North Gyeongsang and North Jeolla Provinces in Korea, were sequenced and compared. The nucleotide sequence identity of the CP gene of eight ASPV isolates ranged from 77.0 to 97.0%, while the amino acid sequence identity ranged from 87.7 to 98.5%. The N-terminal region of the viral CP gene was highly variable, whereas the C-terminal region was conserved. Genetic algorithm recombination detection (GARD) and single breakpoint recombination (SBP) analyses identified base substitutions between eight ASPV isolates at positions 54 and 57 and position 771, respectively. GABranch analysis was used to determine whether the eight isolates evolved due to positive selection. All values in the GABranch analysis showed a ratio of substitution rates at non-synonymous and synonymous sites (dNS/dS) below 1, suggestive of strong negative selection forces during ASPV CP history. Although negative selection dominated CP evolution in the eight ASPV isolates, SLAC and FEL tests identified four possible positive selection sites at codons 10, 22, 102, and 158. This is the first study of the ASPV genome in Korea.

A Study on Optimal Auditing Under the Living Wage System (생계급여하에서의 최적 소득조사)

  • Yoo, Hanwook
    • KDI Journal of Economic Policy
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    • v.31 no.1
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    • pp.207-237
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    • 2009
  • One of the main problems in Korea's public assistance program, the NBLS (National Basic Livelihood Security), is that the loophole of welfare system is continuously growing. Living wage program is the largest sub-program of the NBLS, and the most important determinant of amount of living wage for each beneficiary is the level of reported income. Therefore, accurate and effective income detection is essential in improving policy effects and furthermore reducing the leakage of wage expenditure as beneficiaries always have an incentive to underreport their income. Since most of them do not pay income tax, the welfare authority should exert an independent effort to effectively detect their income. Considering that living wage is a special kind of income tax of which marginal tax rate is -1, one can apply a classical theory of tax evasion to understand illegal or excessive receipt of living wage caused by income underreporting. Utilizing a classical theory given by Alingham and Sandmo (1972), this paper provides a theoretical analysis of the optimal income reporting of the beneficiary. Then an optimization problem is constructed from the government's viewpoint to derive optimal income detecting device (auditing). This paper proves that cut-off discriminated auditing outperforms random auditing and cut-off auditing which implies if the government assigns a positive audit probability to every reported income less than a certain level and the probability is inversely proportional to the level of reported income, it can minimize underreporting and then gradually reduce the leakage of wage expenditure.

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Design of a GCS System Supporting Vision Control of Quadrotor Drones (쿼드로터드론의 영상기반 자율비행연구를 위한 지상제어시스템 설계)

  • Ahn, Heejune;Hoang, C. Anh;Do, T. Tuan
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.41 no.10
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    • pp.1247-1255
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    • 2016
  • The safety and autonomous flight function of micro UAV or drones is crucial to its commercial application. The requirement of own building stable drones is still a non-trivial obstacle for researchers that want to focus on the intelligence function, such vision and navigation algorithm. The paper present a GCS using commercial drone and hardware platforms, and open source software. The system follows modular architecture and now composed of the communication, UI, image processing. Especially, lane-keeping algorithm. are designed and verified through testing at a sports stadium. The designed lane-keeping algorithm estimates drone position and heading in the lane using Hough transform for line detection, RANSAC-vanishing point algorithm for selecting the desired lines, and tracking algorithm for stability of lines. The flight of drone is controlled by 'forward', 'stop', 'clock-rotate', and 'counter-clock rotate' commands. The present implemented system can fly straight and mild curve lane at 2-3 m/s.

Analysis of Dispersion Characteristics of Circumferential Guided Waves and Application to feeder Cracking in Pressurized Heavy Water Reactor (원주 유도초음파의 분산 특성 해석 및 가압중수로 피더관 균열 탐지에의 응용)

  • Cheong, Yong-Moo;Kim, Sang-Soo;Lee, Dong-Hoon;Jung, Hyun-Kyu
    • Journal of the Korean Society for Nondestructive Testing
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    • v.24 no.4
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    • pp.307-314
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    • 2004
  • A circumferential guided wave method was developed to detect the axial crack on the bent feeder pipe. Dispersion curves of circumferential guided waves were calculated as a function of curvature of the pipe. In the case of thin plate, i.e. infinite curvature, as the frequency increases, the $S_0$ and $A_0$ mode coincide and eventually become Rayleigh wave mode. In the case of pipe, however, as the curvature increases, the lowest modes do not coincide even in the high frequencies. Based on the analysis, a rocking technique using angle beam transducer was applied to detect an axial defect in the bent region of PHWR feeder pipe. Based on the analysis of experimenal data for artificial notches, the vibration modes of each signal were identified. It was found that the notches with the depth of )0% of wall thickness can be detected with the method.

Clinical Value of Physical Examination and Electromyography in Acute and Chronic Lumbosacral Radiculopathy (급, 만성 요천추부 신경근병증 환자의 신체진찰과 근전도의 임상적 의미)

  • Jeoung, Ju Hyong;Jeong, Ha Mok;Kang, Seok;Yoon, Joon Shik
    • Clinical Pain
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    • v.19 no.2
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    • pp.90-96
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    • 2020
  • Objective: To investigate the diagnostic accuracy of two physical examinations (straight leg raise [SLR] and Bragard test) and electromyography (EMG) in patients with lumbosacral monoradiculopathy in acute and chronic state on confirmation of different diagnostic criteria (MRI vs MRI and diagnostic selective nerve root block [DSNRB]). Method: We identified 297 participants retrospectively from the departmental database. MRI evidence of L5 or S1 nerve root compression and a positive result in diagnostic SNRB served as reference standards. They were divided into two groups by the symptom duration: lasting more than 12 weeks in the chronic group and less than 12 weeks in the acute group. The diagnostic value of clinical tests and EMG were compared. Results: The clinical tests (SLR and Bragard test) done in acute stage on detection by MRI and DSNRB had the highest sensitivity (68%) compared to the chronic stage (63%), but sensitivity was low (57%) on confirmation of MRI alone. However, there was no significant difference on sensitivity and specificity of EMG regardless of reference standards and symptom duration. Electromyography was a significant predictor of neuropathic abnormalities on both acute (OR, 6.3; 95% CI, 2.4 to 16.7; p<0.01) and chronic (OR, 6.8; 95% CI, 2.9 to 16.3; p<0.01). Conclusion: In general, individual physical tests are easy to do and a combination of those tests could be a sensitive indicator of L5 or S1 radiculopathy. Furthermore, the use of provocation tests could provide useful information, especially in proceeding therapeutic selective nerve root block.

How do diverse precipitation datasets perform in daily precipitation estimations over Africa?

  • Brian Odhiambo Ayugi;Eun-Sung Chung
    • Proceedings of the Korea Water Resources Association Conference
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    • 2023.05a
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    • pp.158-158
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    • 2023
  • Characterizing the performance of precipitation (hereafter PRE) products in estimating the uncertainties in daily PRE in the era of global warming is of great value to the ecosystem's sustainability and human survival. This study intercompares the performance of different PRE products (gauge-based, satellite and reanalysis) sourced from the Frequent Rainfall Observations on GridS (FROGS) database over diverse climate zones in Africa and identifies regions where they depict minimal uncertainties in order to build optimal maps as a guide for different climate users. This is achieved by utilizing various techniques, including the triple collection (TC) approach, to assess the capabilities and limitations of different PRE products over nine climatic zones over the continent. For daily scale analysis, the uncertainties in light PRE (0.1 5mm/day) are prevalent over most regions in Africa during the study duration (2001-2016). Estimating the occurrence of extreme PRE events based on daily PRE 90th percentile suggests that extreme PRE is mainly detected over central Africa (CAF) region and some coastal regions of west Africa (WAF) where the majority of uncorrected satellite products show good agreement. The detection of PRE days and non-PRE days based on categorical statistics suggests that a perfect POD/FAR score is unattainable irrespective of the product type. Daily PRE uncertainties determined based on quantitative metrics show that consistent, satisfactory performance is demonstrated by the IMERG products (uncorrected), ARCv2, CHIRPSv2, 3B42v7.0 and PERSIANN_CDRv1r1 (corrected), and GPCC, CPC_v1.0, and REGEN_ALL (gauge) during the study period. The optimal maps that show the classification of products in regions where they depict reliable performance can be recommended for various usage for different stakeholders.

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