• Title/Summary/Keyword: Attack Potential

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A Study on Dynamic Analysis of Moored Ship Motions by Tsunami (쓰나미에 의한 계류 선박의 동적 동요 해석에 관한 연구)

  • Cho Ik-Soon
    • Journal of Navigation and Port Research
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    • v.29 no.8 s.104
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    • pp.661-666
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    • 2005
  • Recent warnings indicate that there is a potential risk of massive earthquake. These earthquakes could produce large-scale tsunamis. Consideration of the effect of Tsunami to the moored ship is very important bemuse it brings the loss of life and vast property damage in a viewpoint of ship operations within a harbor. If a tsunami occurs, a ship in a harbor may begin drifting in case of ship entering and departing harbor, and breakage of mooring rope and drifting of moored ship are happened. And extremely serious accident, such as stranding and collision to a quay, might occur. On the other hand, since the tsunami consists of approximately component waves of several minutes, there is a possibility of resonance with the long period motion of mooring vessel. As the speed of Tsunami is much faster than tidal current in a harbor, a strong resisting force might act on the moored ships. In this paper, the numerical simulation procedure in the matter of ship motions due to the attack of large-scale tsunamis are investigated and the effects on the ship motions and mooring loads are evaluated by numerical simulation.

Wave Reflections from Breakwaters Having Resonance Channels with Perforated Plates (유공판을 갖는 공진수로 내장형 방파제의 반사특성)

  • Kim, Jeongseok;Seo, Jihye;Lee, Younghoon;Lee, Joongwoo;Park, Woosun
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2013.10a
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    • pp.149-150
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    • 2013
  • Recently, various types of perforated breakwaters are being constructed for protecting offshore storm waves. In general, perforated breakwaters have wave chambers with perforated walls at seaside. Purposes of the wave chambers are to reduce wave reflections and maximum wave forces acting on the breakwater. Impact wave forces due to wave breaking can attack to the perforated wall directly, so the effects have to be considered in the design of the perforated wall carefully. Using resonance channels for wave energy dissipation, a new concept perforated breakwater is proposed, which is free from impact loads. Numerical simulation was made for wave reflection characteristics of the breakwater with respect to major design parameters. Numerical analysis was carried out using the Galerkin's FE model based on the linear potential theory considering energy dissipation on the perforated plate. Variations of wave reflection was investigated according to perforated ratios of perforated plate.

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Detecting CSRF through Analysis of Web Site Structure and Web Usage Patterns (웹사이트 구조와 사용패턴 분석을 통한 CSRF 공격 탐지)

  • Choi, Jae-Yeong;Lee, Hyuk-Jun;Min, Byung-Jun
    • Convergence Security Journal
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    • v.11 no.6
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    • pp.9-15
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    • 2011
  • It is difficult to identify attack requests from normal ones when those attacks are based on CSRF which enables an attacker transmit fabricated requests of a trusted user to the website. For the protection against the CSRF, there have been a lot of research efforts including secret token, custom header, proxy, policy model, CAPTCHA, and user reauthentication. There remains, however, incapacitating means and CAPTCHA and user reauthentication incur user inconvenience. In this paper, we propose a method to detect CSRF attacks by analyzing the structure of websites and the usage patterns. Potential victim candidates are selected and website usage patterns according to the structure and usage logs are analyzed. CSRF attacks can be detected by identifying normal usage patterns. Also, the proposed method does not damage users' convenience not like CAPTCHA by requiring user intervention only in case of detecting abnormal requests.

A Pilot Study of the Effectiveness of a Session of Group Cognitive Behavioral Therapy for Patients with Panic Disorder (공황장애에서 1회기 집단인지행동치료의 효능 ; 예비 연구)

  • Jahng, Eun-Jin;Jeong, Young-Eun;Seo, Ho-Jun;Chae, Jeong-Ho
    • Anxiety and mood
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    • v.5 no.1
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    • pp.36-41
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    • 2009
  • Objectives : The purpose of this pilot study was to investigate the potential clinical benefits a single group session of cognitive behavioral therapy in the treatment of patients with panic disorder. Methods : The study participants were 18 patients (14 males, 4 females; mean age=38.9 years), all of whom were assessed as meeting the DSM-IV-TR criteria for panic disorder. All participants attended one two-hour session of structured group cognitive behavioral therapy (CBT). Clinical symptoms was assessed before and eight weeks after the single therapy session using the Panic Disorder Severity Scale (PDSS). Results : Eight weeks after a single session of group CBT significant improvements were found in panic attack frequency, distress during panic attacks, severity of anticipatory anxiety, agoraphobic fear/avoidance, panic-related sensation fear/avoidance, impairment in work functioning, impairment in social functioning. Conclusions : One session of group CBT appears to be an effective treatment of panic disorder by reducing the severity of all symptoms assessed on the PDSS. An attempt should be made to replicate the findings of this pilot study in a larger and controlled, comparative clinical trial.

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Identification and Expression Profiles of Six Transcripts Encoding Carboxylesterase Protein in Vitis flexuosa Infected with Pathogens

  • Islam, Md. Zaherul;Yun, Hae Keun
    • The Plant Pathology Journal
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    • v.32 no.4
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    • pp.347-356
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    • 2016
  • Plants protect themselves from pathogen attacks via several mechanisms, including hypersensitive cell death. Recognition of pathogen attack by the plant resistance gene triggers expression of carboxylesterase genes associated with hypersensitive response. We identified six transcripts of carboxylesterase genes, Vitis flexuosa carboxylesterase 5585 (VfCXE5585), Vf-CXE12827, VfCXE13132, VfCXE17159, VfCXE18231, and VfCXE47674, which showed different expression patterns upon transcriptome analysis of V. flexuosa inoculated with Elsinoe ampelina. The lengths of genes ranged from 1,098 to 1,629 bp, and their encoded proteins consisted of 309 to 335 amino acids. The predicted amino acid sequences showed hydrolase like domains in all six transcripts and contained two conserved motifs, GXSXG of serine hydrolase characteristics and HGGGF related to the carboxylesterase family. The deduced amino acid sequence also contained a potential catalytic triad consisted of serine, aspartic acid and histidine. Of the six transcripts, Vf-CXE12827 showed upregulated expression against E. ampelina at all time points. Three genes (VfCXE5585, VfCXE12827, and VfCXE13132) showed upregulation, while others (VfCXE17159, VfCXE18231, and VfCXE47674) were down regulated in grapevines infected with Botrytis cinerea. All transcripts showed upregulated expression against Rhizobium vitis at early and later time points except VfCXE12827, and were downregulated for up to 48 hours post inoculation (hpi) after upregulation at 1 hpi in response to R. vitis infection. All tested genes showed high and differential expression in response to pathogens, indicating that they all may play a role in defense pathways during pathogen infection in grapevines.

Distributed Intrusion Detection System for Safe E-Business Model (안전한 E-Business 모델을 위한 분산 침입 탐지 시스템)

  • 이기준;정채영
    • Journal of Internet Computing and Services
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    • v.2 no.4
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    • pp.41-53
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    • 2001
  • Multi-distributed web cluster model built for high availability E-Business model exposes internal system nodes on its structural characteristics and has a potential that normal job performance is impossible due to the intentional prevention and attack by an illegal third party. Therefore, the security system which protects the structured system nodes and can correspond to the outflow of information from illegal users and unfair service requirements effectively is needed. Therefore the suggested distributed invasion detection system is the technology which detects the illegal requirement or resource access of system node distributed on open network through organic control between SC-Agents based on the shared memory of SC-Server. Distributed invasion detection system performs the examination of job requirement packet using Detection Agent primarily for detecting illegal invasion, observes the job process through monitoring agent when job is progressed and then judges the invasion through close cooperative works with other system nodes when there is access or demand of resource not permitted.

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ROLE OF REACTIVE OXYGEN SPECIES IN MALE INFERTILITY

  • Sharma, Rakesh K.;Agarwal, Ashok
    • 대한생식의학회:학술대회논문집
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    • 2000.06a
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    • pp.13-28
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    • 2000
  • Human spermatozoa exhibit a capacity to generate ROS and initiate peroxidation of the unsaturated fatty acids in the sperm plasma membrane, which plays a key role in the etiology of male infertility. The short half-life and limited diffusion of these molecules is consistent with their physiologic role in key biological events such as acrosome reaction and hyperactivation. The intrinsic reactivity of these metabolites in peroxidative damage induced by ROS, particularly $H_2O_2$ and the superoxide anion, has been proposed as a major cause of defective sperm function in cases of male infertility. The number of antioxidants known to attack different stages of peroxidative damage is growing, and it will be of interest to compare alpha-tocopherol and ascorbic acid with these for their therapeutic potential in vitro and in vivo. Both spermatozoa and leukocytes generate ROS, although leukocytes produce much higher levels. The clinical significance of leukocyte presence in semen is controversial. Seminal plasma confers some protection against ROS damage because it contains enzymes that scavenge ROS, such as catalase and superoxide dismutase. A variety of defense mechanisms comprising a number of antioxidants can be employed to reduce or overcome oxidative stress caused by excessive ROS. Determination of male infertility etiology is important, as it will help us develop effective therapies to overcome excessive ROS generation. ROS can have both beneficial and detrimental effects on the spermatozoa and the balancing between the amounts of ROS produced and the amounts scavenged at any moment will determine whether a given sperm function will be promoted or jeopardized. Accurate assessment of ROS levels and, subsequently, OS is Vital, as this will help clinicians both elucidate the fertility status and identify the subgroups of patients that respond or do not respond to these therapeutic strategies. The overt commercial claims of antioxidant benefits and supplements for fertility purposes must be cautiously looked into, until proper multicentered clinical trials are studied. From the current data it appears that no Single adjuvant will be able to enhance the fertilizing capacity of sperm in infertile men, and a combination of the possible strategies that are not toxic at the dosage used would be a feasible approach.

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A Safety Evaluation of Moored Ship Motions by Observed Tsunami Profile

  • Cho, Ik-Soon;Kubo, Masayoshi;Kong, Gil-Young;Lee, Yun-Sok;Lee, Choong-Ro
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.1
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    • pp.47-52
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    • 2006
  • Recent warnings indicate that there is a potential risk of massive earthquake in Japan within 30 years. These earthquakes could produce large-scale tsunamis. Tsunamis are very powerful and can be traveled thousands of miles and caused damage in many countries. Consideration of the effect of tsunami to the moored ship is very important because it brings the loss of life and vast property damage. In this paper, the numerical simulation procedure to analyze the motions of a moored ship due to the observed waves of tsunami, Tokachi-off earthquake tsunami profile in northern Pacific coasts of Japan on September 26 in 2003. And the effects on the motions and mooring loads are investigated by numerical simulation. Numerical simulations consist of hydrodynamic analyses in a frequency domain and ship motion analyses in a time domain as the motions of moored ships are examined. As the process begins, the hydrodynamic and waveexciting forces for moored ships must be calculated. Ship motions and mooring forces can then be calculated by solving the equations of motion. In order to investigate the safety evaluation on the motions of moored ship by tsunami attack, we applied a numerical simulation procedure to a 135,000m3 LNG carrier moored at an offshore sea berth.

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Contrast Analysis for CBRN attacks on educational research and best practices (테러대비를 위한 CBRNE교육 선진사례 분석에 관한 연구)

  • Kim, Tae hwan;Park, Dae woo;Hong, Eun sun
    • Journal of the Society of Disaster Information
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    • v.5 no.1
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    • pp.78-100
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    • 2009
  • This study is to protect peoples' life, minimize the property damage by coping with threats quickly and take more preventive measures in advance against nuclear bomb, CBR, and potential explosive. For this, CBRNE(Chemical, Biological, Radiological, Nuclear, Explosive) program research was used. Thanks to advance in technology, terrorist groups and even individuals make or keep nuclear and CBR weapons. And also it's likely that disaster and threats from a toxic gas, acute pathogens, accidents in the nuclear power plants and a high explosive could be happened a lot. Recently more organized terrorist groups maintain random attacks for unspecified individuals and also it's highly likely that a large-scale terrorist attack by WMD and CBRNEwill be done. To take strict measures against CBRNE attacks by terrorists is on the rise as an urgent national task. Moreover biological weapons are relatively easy and inexpensive to obtain or produce and cause mass casualties with a small amount. For this reason, more than 25 countries have already possessed them. In the 21 st century, the international safety environment marks the age of complicated threats : transnational threats such as comprehensive security and terror, organized crime, drug smuggling, illegal trade of weapons of mass destruction, and environmental disruption along with traditional security threats. These cause military threats, terror threats, and CBRNE threats in our daily life to grow. Therefore it needs to come up with measures in such areas as research development, policy, training program. Major industrial nations on CBRNE like USA, Canada, Switzerland, and Israel have implemented various educational programs. These researches could be utilized as basic materials for drawing up plans for civil defense, emergency services and worldwide countermeasures against CBRNE.

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Against the Effect of Performance Duty Practicing in Psychological Factors of Security Guard (경호원의 심리요인이 임무수행에 미치는 영향)

  • Song, Sang wook;Roh, Jung gu
    • Journal of the Society of Disaster Information
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    • v.5 no.1
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    • pp.48-62
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    • 2009
  • Bodyguards always perform their duty with psychological burdens in their mind, not only because security situations are developed in various forms dependent on the surrounding environments or circumstances, but because bodyguards only take follow-up actions while the criminal decides time, place, and style of every attack. Thus, in the security situation, it is not uncommon for bodyguards to experience muscle rigidity, uncontrollable emotional elevation, difficulty in concentration, negative perception, frustration and enervation, which are caused by continuous physical/mental burdens, stimulations by various interpersonal behaviors or minute environmental stimulants. In conclusion, the result of performing security duties is related in the first place with the degree of the bodyguard's potential, in the second place with the degree of training and efficiency. And the result can also be changed by the way they control their negative psychological state of the moment when they carry out the skills they acquired. Maximizing the performance of the bodyguards by helping them overcome these psychological factors may be facilitated by detecting their psychological factors, understanding the causes, and training them in applying appropriate measures for overcoming these factors. When these measures are applied, the positive perception is indispensable that duties of protecting clients can be carried out successfully. No single measure can be declared to be more effective than the other because the effect of each measure is expressed differently by the individual characteristics of the bodyguards. However, it is important to select and apply the measures most appropriate to the bodyguard. Besides, they should devote themselves to the training with persistence because efficient implement of the measures for overcoming psychological factors takes a lot of time.

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