• Journal of Korean Tunnelling and Underground Space Association
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• v.24 no.4
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• pp.327-339
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• 2022

The purpose of this study is to present the effective smoke control flow rate and mode for securing safety through quantitative risk assessment according to the smoke control flow rate and mode (supply or exhaust) of the platform when a train fire occurs at the subway platform. To this end, a fire outbreak scenario was created using a side platform with a central staircase as a model and fire analysis was performed for each scenario to compare and analyze fire propagation characteristics and ASET, evacuation analysis was performed to predict the number of deaths. In addition, a fire accident rate (F)/number of deaths (N) diagram (F/N diagram) was prepared for each scenario to compare and evaluate the risk according to the smoke control flow rate and mode. In the ASET analysis of harmful factors, carbon monoxide, temperature, and visible distance determined by performance-oriented design methods and standards for firefighting facilities, the effect of visible distance is the largest, In the case where the delay in entering the platform of the fire train was not taken into account, the ASET was analyzed to be about 800 seconds when the air flow rate was 4 × 833 m³/min. The estimated number of deaths varies greatly depending on the location of the vehicle of fire train, In the case of a fire occurring in a vehicle adjacent to the stairs, it is shown that the increase is up to three times that of the vehicle in the lead. In addition, when the smoke control flow rate increases, the number of fatalities decreases, and the reduction rate of the air supply method rather than the exhaust method increases. When the supply flow rate is 4 × 833 m³/min, the expected number of deaths is reduced to 13% compared to the case where ventilation is not performed. As a result of the risk assessment, it is found that the current social risk assessment criteria are satisfied when smoke control is performed, and the number of deaths is the flow rate 4 × 833 m³/min when smoke control is performed at 29.9 people in 10,000 year, It was analyzed that it decreased to 4.36 people.

• Journal of the Daesoon Academy of Sciences
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• v.37
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• pp.263-295
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• 2021

Until recently, academic consensus held that Zhou Dunyi's Taijitu (Taiji Diagram) originated from Cantongqi. However, a new debate has arisen wherein some scholars question that theory and related theories. They criticize these previous theories because the books and charts used as evidence in those theories were published after the lifetime of Zhou Dunyi, and this disqualifies their influence on his thought. However, identifying certain authors as being of a slightly later period than Zhou Dunyi does not definitively answer whether or not Zhou Dunyi's diagram was based on Cantongqi. I approached this problem from a different perspective. Zhou Dunyi's Taijitu is based on the system of taiji (Taiyi), yin-yang, and the five movements. Consequently, the formation of this system should be traced back historically. In the process of tracing it back, I intended to explain that the main character of Cantongqi is closely related to the formation of the system of taiji (Taiyi), yin-yang, and the five movements. The system of taiji (Taiyi), yin-yang, and the five movements was first established as a religious theological system in the Han Dynasty. In this process, yin-yang and the five movements were combined by Dong Zhongshu, and the five movements were introduced by Han Dynasty scholars as a method of interpreting the I-ching. However, Han Dynasty scholars did not form this system. In the late Han Dynasty, Cantongqi adopted the theological system of yin-yang and the five movements to theoretically form the system of taiji (Taiyi), yin-yang, and the five movements. Cantongqi was able to form this system because of the logic that yin-yang is the essence of the I-ching. Cantongqi does not have the same schematic as Taijitu. However, the system of taiji (Taiyi), yin-yang, and the five movements appears and extracts the components that make up Taijitu. Therefore, I do not think we should hastily agree with the recent claims made by scholars.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.5
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• pp.1009-1019
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• 2009

In this research, various characteristics of South Korea's design flood have been examined by deriving appropriate design flood, using data obtained from careful observation of actual floods occurring in selected main watersheds of the nation. 19 watersheds were selected for research in Korea. The various characteristics of annual rainfall were analyzed by using a moving average method. The frequency analysis was decided to be performed on the annual maximum flood of succeeding one year as a reference year. For the 19 watersheds, tests of basic statistics, independent, homogeneity, and outlier were calculated per period of annual maximum flood series. By performing a test using the LH-moment ratio diagram and the Kolmogorov-Smirnov (K-S) test, among applied distributions of Gumbel (GUM), Generalized Extreme Value (GEV), Generalized Logistic (GLO) and Generalized Pareto (GPA) distribution was found to be adequate compared with other probability distributions. Parameters of GEV distribution were estimated by L, L1, L2, L3 and L4-moment method based on the change in the order of probability weighted moments. Design floods per watershed and the periods of annual maximum flood series were derived by GEV distribution. According to the result of the analysis performed by using variation rate used in this research, it has been concluded that the time for changing the design conditions to ensure the proper hydraulic structure that considers recent climate changes of the nation brought about by global warming should be around the year 2002.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.46 no.4
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• pp.148-156
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• 2009

This paper presents a new image rejection algorithm based on the analysis of the distortion of a single-frequency continuous-wave (CW) signal due to the I/Q mismatch. Existing methods estimated the gain mismatch and phase mismatch on RF receivers and compensated them However, this paper shows that the circular trajectory of a single-frequency CW signal is distorted elliptic-type trajectory due to the I/Q mismatch. Utilizing the analysis, we propose a I/Q mismatch compensation method. It has two processing steps. In the first processing step, the generated signal is rotated to align the major axis of the elliptic-type trajectory diagram with the x-axis. In the second processing step, the Q-channel signal in the regenerated signal is scaled to align the regenerated signal with the transmitted single-frequency CW signal. Simulation results show that a receiver using the proposed image rejection algorithm can achieve an image rejection ratio of more than 70dB. And, simulation results show that the bit error rate performances of receivers using the proposed image rejection algorithm are almost the same as those of conventional coherent demodulators, even in fading channels.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.2
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• pp.705-713
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• 2021

Because the cage assembly serves as the launch platform, an accurate aim is essential to ensure shooting accuracy for the target. On the other hand, the abnormal rotation of the cage due to the directional errors of the K-MLRS has continuously caused quality problems. The quality problem of weapon systems may have a negative impact on the military's power loss. In this study, improvement plans were derived by examining the defects and analyzing the directional errors of the K-MLRS launcher. In addition, all possible causes of directional errors were derived from the flow diagram for cage directionality. Based on the results, the defense design through the software program was intended to prevent the loss of direction. Through this study, the signal error of the resolver was improved by preventing unspecific signals in the data. Furthermore, the directional judgment method was improved to minimize the impact of data distortion. Lastly, directional storage and verification methods were improved so that data for the cage rotation direction would not be affected by errors. For the design improvement method, the reliability was verified through the system applicability. This study is expected to be a reference for failure analysis and design for similar weapon systems in the future.

• Journal of Intelligence and Information Systems
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• v.17 no.1
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• pp.17-35
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• 2011

The collective intelligence is a common-based production by the collaboration and competition of many peer individuals. In other words, it is the aggregation of individual intelligence to lead the wisdom of crowd. Recently, the utilization of the collective intelligence has become one of the emerging research areas, since it has been adopted as an important principle of web 2.0 to aim openness, sharing and participation. This paper introduces an approach to seek the collective intelligence by cognition of the relation and interaction among individual participants. It describes a methodology well-suited to evaluate individual intelligence in information retrieval and classification as an application field. The research investigates how to derive and represent such cognitive intelligence from individuals through the application of fuzzy relational theory to personal construct theory and knowledge grid technique. Crucial to this research is to implement formally and process interpretatively the cognitive knowledge of participants who makes the mutual relation and social interaction. What is needed is a technique to analyze cognitive intelligence structure in the form of Hasse diagram, which is an instantiation of this perceptive intelligence of human beings. The search for the collective intelligence requires a theory of similarity to deal with underlying problems; clustering of social subgroups of individuals through identification of individual intelligence and commonality among intelligence and then elicitation of collective intelligence to aggregate the congruence or sharing of all the participants of the entire group. Unlike standard approaches to similarity based on statistical techniques, the method presented employs a theory of fuzzy relational products with the related computational procedures to cover issues of similarity and dissimilarity.

• 대한공업교육학회지
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• v.38 no.2
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• pp.176-194
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• 2013

In this research, 'Construction Technology and Environment' units in 12 different technology home economics textbooks for 1st~3rd year middle school students under the 2009 Revised Educational Curriculum and the content system of textbooks were analyzed based on Reigeluth's elaboration theory, and the following conclusions were derived. First, each of the 12 different textbooks presented the elaboration process by procedural method and composed the content system. Second, the 'Construction Technology and Environment' unit presented many 'Thought Opening' as the systematization strategy of advance learning ability, and 'Unit Summary' presented at the end of the unit as the use strategy of the summarizer was presented preponderantly. In addition, 'Learning Objective' that represents the degree of achievement of the students after learning the unit was presented most as the use strategy of the synthesizer although there are differences in terms. In all of the textbooks, 'Figure,' 'Table,' 'Diagram', and 'Explanation of Terms' were used, and particularly, in the vitalizer strategy of the cognitive strategy, overwhelmingly greater number of 'Figure's, compared with all other elements, were presented as the vitalizer strategy of cognitive strategy. Finally, 'Compensatory Learning,' and 'In-depth Study' were presented as the learner control strategy in each of the 4 different textbooks, and there was one textbook that presents the term 'Supplement Reinforcement' in which compensatory learning and in-depth learning were integrated. Third, the metaphor utilization strategy among the 7 teaching strategies of the elaboration theory was hardly used in the composition items in units of textbooks.

• Archives of design research
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• v.19 no.4 s.66
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• pp.121-132
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• 2006

In the Western Philosophy that was centered on reason, sense has been belittled as a low level of conception under reason. However, the 21st century modern visual environment pushes away the epistemology centered on reason and puts 'sensuality' and 'sense' on its place. Especially, public films are one of the fields that rapidly reflect such changes and lead the changes. However, unfortunately, it is difficult to find such efforts that reflect the artistic and aesthetic significance of sense from the public films. It is because that sense is considered superficial and somewhat not real, while recognizing sense as the low level of conception under reason over the long history. Given the fact, this study reviews the by Gilles Deleuze, a modern philosopher who gives a new value on sense, and it would be meaningful to analyze the works of Chris Cunningham who makes films with the concept of Gilles Deleuze. After we analyzed three music videos of Aphex Twin directed by Chris Cunningham, we can ascertain that the films are based on body without Oranges, hysteric, and diagram that are suggested from by Gilles Deleuze. Analyzing recently released films centered on 'sense' in a superficial manner that includes production method or picture composition, including the films of Chris Cunningham, falls into the error of overlooking the director's aesthetics. Understanding the modern logic of sense that is newly developing, studying its substance, and analyzing the films will make a sacrifice of suggesting a new alternative.

• Korean Journal of Construction Engineering and Management
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• v.14 no.5
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• pp.175-187
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• 2013

Each participant in building construction project requires their own workspace to execute their activities. In this environment, inappropriate workspace planning in construction site causes workspace conflicts which result in a loss of productivity, safety hazard and poor-quality issues. Therefore, workspace should be regarded as one of the most important resources and constraints have to be managed at construction site. However, current construction planning techniques such as Gantt chart, network diagram and critical path method have proven to be insufficient to workspace planning. This paper contains formalized process for workspace planning in 4D BIM environment to prevent workspace related problems in construction project. The proposed process in this paper represents workspace occupation status for each activity and suitable solutions for identified workspace conflicts by integrating workspace attributes and activity execution plan. Based on the result of this study, project manager will be able to prevent probable workspace conflicts and negative effect on project performance by devising appropriate workspace plan during preconstruction phase.

• Journal of the Korean GEO-environmental Society
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• v.21 no.1
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• pp.5-12
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• 2020

Vibration propagated from seismic sources has damping according to distance and amplification and reduction characteristic in different regions according to topography and geological structure. The vibration propagated from the seismic source to the bedrock is largely affected by the damping according to the separation distance, which can be simply estimated through the damping equation. However, it is important to grasp geological information by location because vibration estimation transmitted to the surface are affected by the natural period of the soil located above the bedrock. Geotechnical investigation data are needed to estimate the seismic intensity based on geological information. If there is no Vs profile, the standard penetration tests are mainly used to determine the soil parameters. The Integrated DB Center of National Geotechnical Information manages the geotechnical survey data performed on the domestic ground, and there is the standard penetration test information of 400,000 holes. In this study, the possibility of quantitation the amplification coefficient for each region was examined to calculated the physical interactive seismic intensity based on geotechnical information. At this time, the shear wave column diagram was generated from the SPT-N value and ground response analysis was performed in the target area. The site coefficients for each zone and the seismic intensity distribution for the seismic motion present a significant difference according to the analysis method and the regional setting.