• Journal of the Korea Society for Simulation
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• v.25 no.4
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• pp.127-135
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• 2016

Even thought modernized marine navigation devices help navigators, marine accidents has been often occurred and ship collision is one of the main types of the accidents. Various studies on the assessment method of collision risk have been reported, and studies using fuzzy theory are remarkable for the reason that reflect linguistic and ambiguous criteria for real situations. In these studies, collision risks were assessed on the assumption that the current state of navigation ship would be maintained. However, navigators ignore or turn off frequent alarms caused by the devices predicting collision risk, because they think that they can avoid the collisions in the most of situations. This paper proposes a model of predicting ship collision risk considering the general patterns of collision avoidance, and the approach is based on fuzzy inference and discrete event system specification (DEVS) formalism.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.9 no.6
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• pp.729-738
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• 2019

Recently, we aim to improve the quality of virtual reality contents based on quantitative analysis results of emotions through combination of emotional recognition field and virtual reality field. Emotions are analyzed based on the participant's vital signs. Much research has been done in terms of signal analysis, but the methodology for quantifying emotions has not been fully discussed. In this paper, we propose a normalization function design and expression method to quantify the emotion between various bio - signals. Use the Brute force algorithm to find the optimal parameters of the normalization function and improve the confidence score of the parameters found using the true and false scores defined in this paper. As a result, it is possible to automate the parameter determination of the bio-signal normalization function depending on the experience, and the emotion can be analyzed quantitatively based on this.

• Korean Journal of Construction Engineering and Management
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• v.20 no.2
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• pp.44-52
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• 2019

The frequency and severity of damage caused by extreme climate events are increasing due to climate change. If the infrastructure is not prepared for the risks of climate change, property loss may occur in the facility itself and its surrounding areas. Therefore, climate change adaptation technology should be introduced to reduce future losses. Policy makers need to understand the economic impacts of each technology in order to select an appropriate option. Both the primary damage, which is the direct damage to the facility, and the secondary damage, which is the damage to the surrounding area due to climate change, should all be identified for understanding the economic impact from adaptation. This paper presents a procedure for deriving primary and secondary damage reductions from introducing adaptation technologies and suggests a methodology for evaluating adaptation technology specific to each infrastructure.

• Journal of the Korea Institute of Building Construction
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• v.19 no.2
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• pp.193-200
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• 2019

In the context of increasing threats of EMP by neighboring countries in the security situation on the Korean peninsula, EMP protection facilities are a very important means of ensuring military operational capability. These EMP protection facilities should be constructed by comprehensively judging various factors about operation units. However, Defense Military Facilities Criteria and National Technical Guideline for EMP protection require at least 80dB shielding effectiveness without considering other options. In this study, we use objective and statistical methods to refine the consideration of the required EMP protection level based on the opinions of the experts. To do this, the Delphi technique is used for this study, and the survey was conducted from 53 experts related to EMP protection standard in the military and civilian sectors. The first questionnaire investigated the appropriate level of EMP protection, and the second questionnaire analyzed the factors considered in establishing EMP protection level. As a result of the factor analysis on the opinions of the experts, it was concluded that the EMP protection requirement level should be determined by variables of METT + TC.

• KIPS Transactions on Software and Data Engineering
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• v.8 no.4
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• pp.171-178
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• 2019

The use of anti-scatter grids in radiographic imaging has the advantage of preventing the image distortion caused by scattered radiation. However, it carries the side effect of leaving artifacts in the X-ray image. In this paper, we propose a grid line suppression technique using discrete cosine transform(DCT). In X-ray images, the grid lines have different characteristics depending on the shape of the object and the area of the image. To solve this problem, we adopt the DCT transform based on a dynamic segmentation, and propose a filter transfer function for each individual segment. An algorithm for detecting the band of grid lines in frequency domain and a band stop filter(BSF) with a filter transfer function of a combination of Kaiser window and Butterworth filter have been proposed. To solve the blocking effects, we present a method to determine the pixel values using multiple structured images. The validity of the proposed theory has been evaluated from the experimental results using 140 X-ray images.

• Journal of the Korea Institute of Building Construction
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• v.19 no.2
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• pp.167-174
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• 2019

Protective facilities are the last means of ensuring the survivability of personnel and assets, and there is a greater amount of matters to consider than those of general buildings. However, the Defense Military Facilities Criteria and the Ministry of the Interior and Safety, Ordinance No. 20, are only considering the expected enemy threats. In this study, we use objective and statistical methods to refine the consideration of the required capacity of protection based on the opinions of the experts. Specifically, the study adopts the Delphi technique associating the experts related to 30 defense military facilities criteria. The first-round questions were open-ended, and it compiled the points to consider related to the bulletproof and explosion - proof design. The second questionnaire was applied as closed questionnaire with 7 points scale methods. As a result of the factor analysis on the opinions of the experts, it was confirmed that the protection requirement level was due to METT + TC.

• Journal of the Korea institute for structural maintenance and inspection
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• v.12 no.4
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• pp.195-202
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• 2008

Underestimation of the capacity can have serious economic consequences, as deficient bridges must be posted, repaired or replaced. Accurate prediction of bridge behavior may allow for more bridges to remain in service with or without minor repairs. The presented research is focused on the reliability evaluation of the actual load carrying capacity of existing bridges based on the field testing. Reliability analysis is performed on 17 previously tested bridges. Bridges are first evaluated based on the code specified values and design resistance. However, after the field testing program, it is possible to apply the experimental results into the bridge reliability evaluation procedures. The girder distribution factors obtained from the tests are also applied in the reliability calculation. The results indicate that the reliability indices of selected bridges can be significantly increased due to the reduction of uncertainties without sacrificing the safety of structures, by including the result of field measurement data into calculation.

• Journal of KIISE:Software and Applications
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• v.36 no.9
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• pp.732-748
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• 2009

The technology of Semantic Web realizes the base technology for context-awareness that creates new services by dynamically and flexibly combining various resources (people, concepts, etc). According to the realization of ubiquitous computing technology, many researchers are currently working for the embodiment of web service. However, most studies of them bring about the only predefined results those are limited to the initial description by service designer. In this paper, we propose a new service supporting model to provide an automatic method for plan related tasks which achieve goal state from initial state. The inputs on an planner are intial and goal descriptions which are mapped to the current situation and to the user request respectively. The idea of the method is to infer context from world model by DL-based ontology reasoning using OWL domain ontology. The context guide services to be loaded into planner. Then, the planner searches and plans at least one service to satisfy the goal state from initial state. This is STRIPS-style backward planner, and combine OWL-S services based on AI planning theory that enabling reduced search scope of huge web-service space. Also, when feasible service do not find using pattern matching, we give user alternative services through DL-based semantic searching. The experimental result demonstrates a new possibility for realizing dynamic service modeler, compared to OWLS-XPlan, which has been known as an effective application for service composition.

• Journal of Korean Society of Transportation
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• v.24 no.5 s.91
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• pp.35-44
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• 2006

Acceleration and deceleration curves have been used for design purposes worldwide. The curve in design level has been regarded as an single deterministic curve to be used for design of climb lanes. It should be noted that the curve was originally made using ideal driving truck and that the curve is applied during design based on the assumption of no difference between ideal and real driving conditions. However. observations show that aged vehicles and lazy behavioring drivers nay make lower performance of vehicles than the ideal performance. The present paper provides the results of truck speeds at climbing lanes then probabilistic variation of acceleration and deceleration corves. For these purposes. a study about identification of vehicle makers, and weights for trucks at freeway toll gates and then observation of vehicle-following speed were performed. The 85%ile results obtained were compared with the deterministic performance curves of 180, 200, and 220 Ib/hp. It was identified that the performance of 85%ile results obtained from vehicle-following-speed observations were lower than one from deterministic performance curves. From these results, it may be concluded that at the beginning Point of climbing lanes additional $16.19{\sim}67.94m$ is necessary and that at the end point of climbing lanes $53.12{\sim}103.24m$ of extension is necessary.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.4
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• pp.78-90
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• 2010

This research tried to suggest a method of DB construction in the field using evaluation variables and Mobile GIS focusing on Changwon City as a leading study to encourage walking and biking in everyday life. First, twenty evaluation variables of WEs(walking environments) were selected through the literature review, and also scored separately. Second, the field survey-DB of each variable was built effectively using Mobile GIS. Finally, WEs were evaluated synthetically based on the obtained data. The results of this research are summarized as follows. While the WE of the zones located in the fringe of Changwon square were generally got a high score as over 42, other zones located in detached or row house area were evaluated relatively highly bad. Findings from this research will help in determining the zone required improvement of WEs or easy access to main destination such as a park, shopping center, school, etc. and also selecting variables of WEs, needed an intensive improvement, in the selected zone after comparing the results of field and questionnaire survey. Furthermore, those will be used as a means of decision making support for planing, designing and maintaining of WEs to promote people's physical activity in their daily lives.