• International Journal of Computer Science & Network Security
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• v.24 no.5
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• pp.205-211
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• 2024

The increasing number of botnet attacks incorporating new evasion techniques making it infeasible to completely secure complex computer network system. The botnet infections are likely to be happen, the timely detection and response to these infections helps to stop attackers before any damage is done. The current practice in traditional IP networks require manual intervention to response to any detected malicious infection. This manual response process is more probable to delay and increase the risk of damage. To automate this manual process, this paper proposes to automatically select relevant countermeasures for detected botnet infection. The propose approach uses the concept of flow trace to detect botnet behavior patterns from current and historical network activity. The approach uses the multiclass machine learning based approach to detect and classify the botnet activity into IRC, HTTP, and P2P botnet. This classification helps to calculate the risk score of the detected botnet infection. The relevant countermeasures selected from available pool based on risk score of detected infection.

• The Journal of Korean Physical Therapy
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• v.16 no.1
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• pp.208-246
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• 2004

The purpose of this study was to investigate the effect of aqua exercise program on the static balance of child with mental retardation. The subjects were seven male child and three female child with mental retardation(age ranges from 5 to 6). The subjects were practiced with focusing on the aqua exercise program for 8 weeks, from 7, January 2003 to 28, February 2003. The results of this study were as follows : 1. After the exercise program, the balance of double-stance by BPM was significantly reduced of lateral sway number by $12.2\%$(P<.01) with eyes obstruct. 2. After the exercise program, the balance of double-stance by BPM was significantly reduced of anterior and posterior sway number of left leg by $8.5\%$(P<.05) with eyes obstruct. 3. After the exercise program, the balance of double-stance by BPM was significantly reduced of anterior and posterior sway number of right leg by $8.3\%$(P<.05) with eyes obstruct. 4. After the exercise program, the balance of double-stance by BPM was significantly reduced of lateral sway number by $13.2\%$(P<.01) with eyes open. 5. After the exercise program, the balance of double-stance by BPM was significantly reduced of anterior and posterior sway number of left leg by $10.3\%$(P<.05) with eyes open. 6. After the exercise program, the balance of double-stance by BPM was significantly reduced of anterior and posterior sway number of right leg by $10.3\%$(P<.01) with eyes open. As we can see the results of this study, the aqua exercise program improved the static balance of child with mental retardation. Futhermore, it is reasonable program that can improvability of static balance for the children with mental retardation using aqua exercise program. And then it is necessary to develop much better program than now for the children with mental retardation's health and to provide the adequate pool for their aqua exercise.

• Journal of the Korean Institute of Gas
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• v.16 no.6
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• pp.29-33
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• 2012

This paper is an attempt to give a concise overview of the state-of-the-art in the recent liquid hydrogen safety researches with unwanted event progress. The vessel of liquified hydrogen may fail and liquid hydrogen spilled. The hydrogen will immediately start to evaporate above a pool and make a hydrogen cloud. The cloud will disperse and can produce a vapor cloud explosion. The vessel containing the liquid hydrogen may not be able to cope with the boil-off due to heat influx, especially in case of a fire, and a BLEVE may occur. In equipment where it exists as compressed gas, a leak generates a jet of gas that can self-ignite immediately or after a short delay and produce a jet flame, or in case it ignites at a source a certain distance from the leak (delayed ignition), a flash fire occurs in the open and with confinement a deflagration or even detonation may develop. The up-to-date knowledge in these events, recent progress and future research are discussed in brief.

• The Korean Journal of Nuclear Medicine
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• v.19 no.1
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• pp.67-72
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• 1985

The development of paradoxical interventricular septal motion is a common consequence of cardiopulmonary bypass operation. The reason for this postoperative abnormal septal motion is not clear. 41 patients were studied preoperatively and postoperatively with radionuclide blood pool scan to evaluate the frequency of development of paradoxical septal motion with right ventricular volume overload before surgery and the frequency of development of paradoxical septal motion after cardiac surgery with cardiopulmonary bypass, and to evaluate the change of EF related to the development of paradoxical septal motion after cardiac surgery. The results were as follows; 1) 7 of 41 patients with right ventricular volume overload(that is 17%) showed paradoxical septal motion before surgery. But 13 of 34 patients(that is 42%) had paradoxical septal motion after cardiac surgery with cardiopulmonary bypass. So open heart surgery with cardiopulmonary bypass related the development of paradoxical septal motion after surgery. 2) EF significantly decreased in patients who developed paradoxical septal motion after surgery, whereas the EF did not change in the patients who retained normal interventricular septal motion after surgery. So paradoxical septal motion usually reflected some diminution of left ventricular function, immediately after cardiac surgery.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.3 no.4
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• pp.21-31
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• 1983

Circulation phenamena in open channel with abrupt variation in flow section are studied by solving numerically two dimensional Navier-Stokes equations integrated over depth. Galerkin type finite element method is used as numerical scheme. Numerical results by both implicit and explicit schemes tested in one-demensional rectangular channel agree closely with the known solution. The numerical experiments carded out in the open channel with a pool indicate the expected flow pattern and the center of the circulation coincides with the geometrical center, but the vectors of velocity appear father small, and it remains to be further investigated. Numerically simulated flow profiles along the channel with constrictions such as bridge piers and abutments are shown to be close to hydraulic experimental results. Thus further refined numerical technique is expected to be able to serve as a tool to evaluate the effect of bridge backwater.

• Journal of the Korean Society for information Management
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• v.37 no.3
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• pp.221-252
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• 2020

According to the participants, the current K-MOOC (Korean Massive Open Online Course) has a few problems, such as too few courses, low content quality, and useless learner management system compared to MOOCs abroad. These problems caused diminished learner motivation. Consequently, the K-MOOC service has recorded a low course completion rate despite high expenses spent to develop the contents and thus requires remedies to fix the issues. This study drew research subjects from a pool of college and graduate students representing the primary users of the K-MOOC. This study limited the research scope to the four categories: motivation, learning experience, recognition, and performance of the Biggs' 3P Learning System Model. Based on the literature review, ten variables were selected and explored how the subjects perceived four categories using the survey questionnaire. This study also examined the relationship between ten variables and generated suggestions for the instructors, course managers, and platform developers to make the K-MOOC better.

• Journal of the Korean Institute of Landscape Architecture
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• v.18 no.4
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• pp.127-140
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• 1991

The Primary purpose of this study is to investigate factors and variables which have significant effects on user satisfaction with recreational facilities in Taejong-Dae recreational complex, thereby establishing indices of planning and development of urban parks and open space. To test the causal models of this research, the date were gathered by self-administered questionnaires from 967 households in Pusan City which were selected by the multi-stage probability sampling methood. The analysis of the multi-stage primarily consists of two phase : The first analysis dealt exploratory factor analysis which identified major factors involved in satisfaction with recreational activities and facilities in Taejong-Dae recreational complex and the second analysis tested the fit of the causal models of this research by employing LISREL methodology. There are three advantages of using LISREL over other multivariate analysis methods : First, measurement error is allowed and calculated in LISREL, otherwise there is a risk of seriously misleading estimates of coefficients ; Second, LISREL deals with latent variables or unmeasured variables ; Third, it enables to test causal relations among variables. The factors analysis identified that five factors are involved in satisfaction with recreational facilities. The five factors of satisfaction with recreational facilities are space for repose and relaxation, active recreation facilities such as pool and zoo, physical exercise facility, convenience and maintenance facility, and linear facility, and linear facility for walking. The second phase analysis tested the fit of the causal models for satisfaction with recreational facilities to the data and identified statistically significant causal linkage among overall satisfaction with Taejong-Dae recreational complex, other endogenous factors and exogenous variables. Overall fits of both causal models were very good. Among endogenous factors, facility for repose and relaxation. linear facility for walking, active recreation facility, facility for convenience and maintenance were identified as having significant effects on overall satisfaction. Exogenous variables which have significant effects on endogenous variables wer also identified. These significant relationships indicate important factors and variables that should be considered in planning and development of the recreational complex. On the basis of these significant causal relationships, implications for planning and the delovepment of Taejong-Dae recreational complex were suggested.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.815-820
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• 2003

A huge database resulted from whole genome sequencing has provided a possibility of new information that is likely to extent the scope and thus changes the way of approach for the functional assigning of putative open reading frames annotated by whole genome sequence analyses. These are mainly realized by ease, one-step identification of putative genes using genomics or proteomics tools. A major challenge remained in biotechnology may translate these informations into better ways to screen or select a gene as a representative sequence. Further attempts to mine the related whole genes or partial DNA fragment from whole genome treasure, and then the incorporation of these sequences into a representative template, will result in the use of putative genes that can be translated into functional proteins or allowed the generation of new lineages as a valuable pool. Such screens enable rapid biochemical analysis and easy isolation of the target activity, thereby accelerating the screening of novel enzymes from the expanded library with related sequences. Information-based PCR amplification of whole genes and reconstitution of functional DNA fragments will provide a platform for expanding the functional spaces of potential enzymes, especially when used mixed- or metagenome as gene resources.

• 유체기계공업학회:학술대회논문집
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• 2002.12a
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• pp.419-424
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• 2002

The HANARO, a multi-purpose research reactor of 30 MWth open-tank-in-pool type, has been under normal operation since its initial criticality In February, 1995. Many experiments should be safely performed to activate the utilization of the HANARO. A flow simulation facility is being developed for the endurance test of reactivity control units for extended life times and the verification of structural integrity of those experimental facilities prior to loading in the HANARO. This test facility is composed of three major parts; a half-core structure assembly, flow circulation system and support system. The flow circulation system is composed of a circulation pump, a core flow pipe, a core bypass flow pipe and instruments. The system is to be filled with de-mineralized water and the flow should be met the design flow to simulate similar flow characteristics in the core channel of the half-core test facility to the HANARO. This paper, therefore, describes an analytical analysis to study the flow behavior of the system. The computational flow analysis has been performed for the verification of system pressure variation through the three-dimensional analysis program with standard k-$\epsilon$ turbulence model and for the verification of the structural piping integrity through the finite element method. The results of the analysis are satisfied the design requirements and structural piping integrity of flow circulation system.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.425-429
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• 2006

The understanding and prediction of the behavior of flow in open channels are important to the solution of a wide variety of practical flow problems in water resources engineering. Recently, frequent drought has increased the necessity of an effective water resources control and management of river flows for reserving instream flow. The objective of this study is to develop an efficient and accurate finite element model based on Streamline Upwind/Petrov-Galerkin(SU/PG) scheme for analyzing and predicting two dimensional flow features in complex natural rivers. Several tests were performed in developed all elements(4-Node, 6-Node, 8-Node elements) for the purpose of validation and verification of the developed model. The U-shaped channel of flow and natural river of flow were performed for tests. The results were compared with these of laboratory experiments and RMA-2 model. Such results showed that solutions of high order elements were better accurate and improved than those of linear elements. Also, the suggested model displayed reasonable velocity distribution compare to RMA-2 model in meandering domain for application of natural river flow. Accordingly, the developed finite element model is feasible and produces reliable results for simulation of two dimensional natural river flow. Also, One contribution of this study is to present that results can lead to significant gain in analyzing the accurate flow behavior associated with hydraulic structure such as weir and water intake station and flow of chute and pool.