• Title/Summary/Keyword: event detection

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Development of Landslide Detection Algorithm Using Fully Polarimetric ALOS-2 SAR Data (Fully-Polarimetric ALOS-2 자료를 이용한 산사태 탐지 알고리즘 개발)

  • Kim, Minhwa;Cho, KeunHoo;Park, Sang-Eun;Cho, Jae-Hyoung;Moon, Hyoi;Han, Seung-hoon
    • Economic and Environmental Geology
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    • v.52 no.4
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    • pp.313-322
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    • 2019
  • SAR (Synthetic Aperture Radar) remote sensing data is a very useful tool for near-real-time identification of landslide affected areas that can occur over a large area due to heavy rains or typhoons. This study aims to develop an effective algorithm for automatically delineating landslide areas from the polarimetric SAR data acquired after the landslide event. To detect landslides from SAR observations, reduction of the speckle effects in the estimation of polarimetric SAR parameters and the orthorectification of geometric distortions on sloping terrain are essential processing steps. Based on the experimental analysis, it was found that the IDAN filter can provide a better estimation of the polarimetric parameters. In addition, it was appropriate to apply orthorectification process after estimating polarimetric parameters in the slant range domain. Furthermore, it was found that the polarimetric entropy is the most appropriate parameters among various polarimetric parameters. Based on those analyses, we proposed an automatic landslide detection algorithm using the histogram thresholding of the polarimetric parameters with the aid of terrain slope information. The landslide detection algorithm was applied to the ALOS-2 PALSAR-2 data which observed landslide areas in Japan triggered by Typhoon in September 2011. Experimental results showed that the landslide areas were successfully identified by using the proposed algorithm with a detection rate of about 82% and a false alarm rate of about 3%.

Research status of the development of genetically modified papaya (Carica papaya L.) and its biosafety assessment (GM 파파야 개발 및 생물안전성 평가 연구 동향)

  • Kim, Ho Bang;Lee, Yi;Kim, Chang-Gi
    • Journal of Plant Biotechnology
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    • v.45 no.3
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    • pp.171-182
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    • 2018
  • Papaya (Carica papaya L.) is one of the crops widely planted in tropical and subtropical areas. The papaya fruit has low calories and are plentiful in vitamins A and C and in minerals. A major problem in papaya production is a plant disease caused by the papaya ringspot virus (PRSV). The first PRSV-resistant GM papaya expressing a PRSV coat protein gene was developed by USA scientists in 1992. The first commercial GM papaya cultivars derived from the event was approved by the US government in 1997. Development of transgenic papayas has been focused on vaccine production and limited agricultural traits, including insect and pathogen resistance, long shelf life, and aluminum and herbicide tolerance. Approximately 17 countries, including the USA and China, produced transgenic papayas and/or commercialized them, which provoked studies on biosafety assessment and development of GM-detection technologies. For the biosafety assessment of potential effects on human health, effects of long-term feeding to model animals have been studied in terms of toxicity and allergenicity. Studies on environmental safety assessment include influence on soil-microbial biodiversity and transfer to soil bacteria of GM selection markers. Many countries, such as Korea, the European Union, and Japan, that have strict regulations for GM crops have serious concerns about unintended introduction of GM cultivars and food commodities using unauthorized GM crops. Transgene- and/or GM event-specific molecular markers and technologies for genomics-based detection of unauthorized GM papaya have been developed and have resulted in the robust detection of GM papayas.

Prognostic Implication of Normal Myocardial Perfusion Scintigraphy in Patients with Chest Pain (정상 심근관류신티그라피 소견을 보인 흉통환자의 예후)

  • Song, Ho-Cheon;Min, Jung-Jun;Kim, Ji-Yeul;Bom, Hee-Seung
    • The Korean Journal of Nuclear Medicine
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    • v.31 no.1
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    • pp.67-72
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    • 1997
  • Myocardial scintigraphy is a widely used noninvasive procedure with high sensitivity for the detection of patients with suspected coronary artery disease. The purpose of this study was to determine the prognostic value of a normal myocardial scintigraphy in 292 patients (150 males, 142 females, mean age $53{\pm}12$ years) with chest pain who were followed from 7 to 58 (mean 25) months. Myocardial SPECT was performed with Tc-99m MIBI in 173 patients, with Tc-99m tetrofosmin in 74 patients and with T1-201 in 45 patients. During the follow-up period, there were 2 cardiac deaths and 2 nonfatal myocardial infarctions resulting in cardiac event rate of 1.37% (0.66% Per Year). The cardiac event rate was not different in patients with angiographically normal coronary arteries (1/30, 3.3%) and in those who had significant coronary artery disease (2/27, 7.4%) (p=0.60). In conclusion, patients with chest pain and normal myocardial scintigraphy have a low cardiac event rate, and there was no significant difference of. cardiac event rates between patients with normal and abnormal coronary angiograms.

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RADIAL AND AZIMUTHAL OSCILLATIONS OF HALO CORONAL MASS EJECTIONS

  • Lee, Harim;Moon, Y.J.;Nakariakov, V.M.
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.1
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    • pp.66.1-66.1
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    • 2015
  • We present the first observational detection of radial and azimuthal oscillations in full halo coronal mass ejections (HCMEs). We analyze nine HCMEs well-observed by LASCO from Feb 2011 to Jun 2011. Using the LASCO C3 running difference images, we estimated the instantaneous apparent speeds of the HCMEs in different radial directions from the solar disk center. We find that the development of all these HCMEs is accompanied with quasi-periodic variations of the instantaneous radial velocity with the periods ranging from 24 to 48 mins. The amplitudes of the instant speed variations reach about a half of the projected speeds. The amplitudes are found to anti-correlate with the periods and correlate with the HCME speed, indicating the nonlinear nature of the process. The oscillations have a clear azimuthal structure in the heliocentric polar coordinate system. The oscillations in seven events are found to be associated with distinct azimuthal wave modes with the azimuthal wave number m=1 for six events and m=2 for one event. The polarization of the oscillations in these seven HCMEs is broadly consistent with those of their position angles with the mean difference of $42.5^{\circ}$. The oscillations may be connected with natural oscillations of the plasmoids around a dynamical equilibrium, or self-oscillatory processes, e.g. the periodic shedding of Alfvenic vortices. Our results indicate the need for advanced theory of oscillatory processes in CMEs.

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Iron supplement tablet embedded in the oral cavity mimicking neoplasm: a case report

  • Corliano, Fabrizio;Falco, Paola;Cambi, Jacopo;Brindisi, Leopoldo
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.42 no.2
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    • pp.111-114
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    • 2016
  • The detection of foreign bodies in the upper-aerodigestive tract is a fairly frequent event and can occur in various areas and for various reasons. In rare cases, foreign bodies can simulate a neoplasia. We evaluated similar cases during emergency regimen with an oral cavity mucosal lesion, causing lockjaw, sore throat, dysphagia, and swelling of the submandibular and laterocervical region. Physical examination revealed an extensive mucosal ulceration in the floor of the mouth and the lateral surface of the tongue, comparable to oral cancer. During a second, more accurate assessment, a partially deteriorated iron supplement tablet was found embedded in a mucosal pocket. After removing the tablet, gradual normalization of the tissue was observed without any sequelae. This is one of the many reasons why it is advisable and useful in cases of oral lesions to collect a detailed medical history and to perform an accurate clinical evaluation, including inspection and palpation of the lesion, before proceeding to further diagnostic assessments, especially in elderly patients taking many medications. However unlikely, it is possible that difficulty in swallowing pills or tablets could generate tumorlike lesions.

A study on Classification of Insider threat using Markov Chain Model

  • Kim, Dong-Wook;Hong, Sung-Sam;Han, Myung-Mook
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.4
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    • pp.1887-1898
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    • 2018
  • In this paper, a method to classify insider threat activity is introduced. The internal threats help detecting anomalous activity in the procedure performed by the user in an organization. When an anomalous value deviating from the overall behavior is displayed, we consider it as an inside threat for classification as an inside intimidator. To solve the situation, Markov Chain Model is employed. The Markov Chain Model shows the next state value through an arbitrary variable affected by the previous event. Similarly, the current activity can also be predicted based on the previous activity for the insider threat activity. A method was studied where the change items for such state are defined by a transition probability, and classified as detection of anomaly of the inside threat through values for a probability variable. We use the properties of the Markov chains to list the behavior of the user over time and to classify which state they belong to. Sequential data sets were generated according to the influence of n occurrences of Markov attribute and classified by machine learning algorithm. In the experiment, only 15% of the Cert: insider threat dataset was applied, and the result was 97% accuracy except for NaiveBayes. As a result of our research, it was confirmed that the Markov Chain Model can classify insider threats and can be fully utilized for user behavior classification.

WSN Lifetime Analysis: Intelligent UAV and Arc Selection Algorithm for Energy Conservation in Isolated Wireless Sensor Networks

  • Perumal, P.Shunmuga;Uthariaraj, V.Rhymend;Christo, V.R.Elgin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.3
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    • pp.901-920
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    • 2015
  • Wireless Sensor Networks (WSNs) are widely used in geographically isolated applications like military border area monitoring, battle field surveillance, forest fire detection systems, etc. Uninterrupted power supply is not possible in isolated locations and hence sensor nodes live on their own battery power. Localization of sensor nodes in isolated locations is important to identify the location of event for further actions. Existing localization algorithms consume more energy at sensor nodes for computation and communication thereby reduce the lifetime of entire WSNs. Existing approaches also suffer with less localization coverage and localization accuracy. The objective of the proposed work is to increase the lifetime of WSNs while increasing the localization coverage and localization accuracy. A novel intelligent unmanned aerial vehicle anchor node (IUAN) is proposed to reduce the communication cost at sensor nodes during localization. Further, the localization computation cost is reduced at each sensor node by the proposed intelligent arc selection (IAS) algorithm. IUANs construct the location-distance messages (LDMs) for sensor nodes deployed in isolated locations and reach the Control Station (CS). Further, the CS aggregates the LDMs from different IUANs and computes the position of sensor nodes using IAS algorithm. The life time of WSN is analyzed in this paper to prove the efficiency of the proposed localization approach. The proposed localization approach considerably extends the lifetime of WSNs, localization coverage and localization accuracy in isolated environments.

Mini Neutron Monitors at Concordia Research Station, Central Antarctica

  • Poluianov, Stepan;Usoskin, Ilya;Mishev, Alexander;Moraal, Harm;Kruger, Helena;Casasanta, Giampietro;Traversi, Rita;Udisti, Roberto
    • Journal of Astronomy and Space Sciences
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    • v.32 no.4
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    • pp.281-287
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    • 2015
  • Two mini neutron monitors are installed at Concordia research station (Dome C, Central Antarctica, $75^{\circ}06^{\prime}S$, $123^{\circ}23^{\prime}E$, 3,233 m.a.s.l.). The site has unique properties ideal for cosmic ray measurements, especially for the detection of solar energetic particles: very low cutoff rigidity < 0.01 GV, high elevation and poleward asymptotic acceptance cones pointing to geographical latitudes > $75^{\circ}S$. The instruments consist of a standard neutron monitor and a "bare" (lead-free) neutron monitor. The instrument operation started in mid-January 2015. The barometric correction coefficients were computed for the period from 1 February to 31 July 2015. Several interesting events, including two notable Forbush decreases on 17 March 2015 and 22 June 2015, and a solar particle event of 29 October 2015 were registered. The data sets are available at cosmicrays.oulu.fi and nmdb.eu.

Paradoxical Lateralization of Convulsive Movements in a Subtle Status Epilepticus (미세 간질중첩증에서의 역설적 편측화)

  • Sohn, Eun-Hee;Jung, Ki-Young;Kim, Jae-Moon
    • Annals of Clinical Neurophysiology
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    • v.4 no.2
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    • pp.137-139
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    • 2002
  • Background : Subtle status epilepticus (SE) is an end-stage of convulsive SE. This phenomenon might be a clinical expression of neuronal exhaustion caused by sustained electrical discharges. As subtle SE may show diverse clinical features, early detection depends on clinical suspicion. Case : A 68-year-old woman was presented with repetitive involuntary movement of right limbs after two generalized tonic-clonic seizures. She experienced right middle cerebral artery infarction 4 months ago, and after the event, left side hemiplegia sustained. These seizures were first-ever after the cerebral infarction. Orientation and verbal responses were fairly preserved but general cognitive function was minimally slowed. During the video-EEG monitoring, repetitive sharp waves were noted in the right hemisphere and these sharp waves occasionally spread to the contralateral side. Her right side involuntary movement was identifiable when the epileptic discharges were found on her right hemisphere. Conclusion : We suggested that this unexpected convulsive movement is a reflection of earlier exhaustion in the right hemisphere or deefferentation of right hemisphere because of preexisting neuronal damage.

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Analysis of in vitro apoptosis induced by virulent Korean isolate of classical swine fever virus in peripheral blood B cell line

  • Kim, Seon-Mi;Lim, Seong-In;Song, Jae-Young;Hyun, Bang-Hun
    • Korean Journal of Veterinary Research
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    • v.52 no.4
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    • pp.259-262
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    • 2012
  • Classical swine fever (CSF) is a highly contagious disease among swine that has an important economic impact on worldwide. One clinical symptom of CSF is leukopenia, in particular lymphopenia, which is a characteristic event that occurs early in the course of CSF. Though lymphopenia associated with apoptosis, the pathogenic mechanism underlying the lymphopenia has not been well studied. To understand these mechanisms, we investigated the response of porcine B cell lines to infection with SW03, virulent strain isolated from swine tissue in Korea. This study demonstrated that SW03-infected L35 cell were induced apoptosis through the detection of activated caspase-3. In addition, SW03 infection leaded to alterations in pro-apoptotic, Bax, and anti-apoptotic, Bcl-xL proteins of Bcl-2 family. Our results would suggest that SW03-infected L35 cells induced apoptosis via intrinsic mitochondrial pathway.