• Journal of Advanced Navigation Technology
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• v.5 no.2
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• pp.123-133
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• 2001

The existing visualization methods using the satellite images or map images require complicated preprocessing stages and a large amount of visual data to represent the 3-D terrain. This paper presents a 3-D visualization method for geographical information, which enables automatic generation of 3-D terrain. It is generated based, on contour information obtained from a numerical map. This paper also introduces a method that resolves the three main problems needed to visualize 3-D terrain from contour lines such as correspondence, tiling, and branching. The virtual contour line is defined to extend a distorted contour line to have a similar shape to the corresponding contour line that is used, to generate 3-D surfaces. It helps that 3-D terrain is represented exactly and in detail.

• Journal of Korean Medical classics
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• v.27 no.1
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• pp.99-109
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• 2014

Objectives : The concepts of many Korean medicine terms have changed for a long time and cumulatively been recorded in later medicine literatures. And, the same terms have very often been used for different meanings depending on context. Methods : This study was performed so that conceptual magnitude of Korean medicine terms could intuitively be recognized for the purpose of quantization. Results : This study was performed under the premise that terms used in old literatures of Korean medicine are related mostly to treatments that could immediately be reverted to types of medical herbs used. Through this, conceptual magnitude of terms was quantified by the method that frequency of medical herbs used for treatment was changed to numerical values. For this, data of "Compilation of Formulas and Medicinals Addendum" were used. First, after 'specificity' of each medicine herb corresponding to representative disease symptoms was calculated, medians in the set were selected, and 'values of conceptual magnitude' for representative disease symptoms were calculated. Conclusions : As a result, if disease symptoms are diverse, concept range is diachronically changed greatly, and specific disease symptoms of great conceptual difference are included, value of conceptual magnitude was great. Meanwhile, if disease factor and treatment are singular or limited to several types, and many medical herbs with high specificity are used, value of conceptual magnitude was less.

• Journal of Korean Medical classics
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• v.33 no.4
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• pp.1-19
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• 2020

Objectives : This paper aims to understand the meaning and utilitarian values of 'Jongyong(從容)' in medicine by studying its meaning in the 『Huangdineijing』. Methods : Examples of 'Jongyong(從容)' usages in Chinese literature and classical texts were studied first. Next, the similarities and characteristics of its contexts in discourses between Leigong and Huangdi were examined, followed by further examination of the overall meanings of the six chapters, 「Shicongronglunpian(示從容論篇)」, 「Zhuzhijiaolunpian(著至敎論篇)」, 「Shuwuguolunpian(疏五過論篇)」, 「Zhengsishilunpian(徵四失論篇)」, 「Yinyangleilunpian(陰陽類論篇)」, 「Jiejingweilunpian(解精微論篇)」 and the verses that include 'Jongyong(從容).' Results : Generally 'Jongyong(從容)' describes a resilient attitude that responds appropriately and calmly to difficult external situations while maintaining one's character, or refers to one's general behavior. In the 『Huangdineijing』, 'Jongyong(從容)' is only mentioned in discourses between Leigong and Huangdi, which talks about ancient East Asian clinical medicine in general, its transmission and education. Here, the meaning of 'Jongyong(從容)' could be summarized as an expansion of analogical thinking[引比類], medical work that involves the physician's commitment(人事), and detailed measurement of yinyang difference in the body(刑法, 陰陽, 治數). Discussion : In ancient East Asian medicine, the meaning of 'Jongyong(從容)' is closer to measurement of the yinyang difference rather than differentiation of the five element analogy. It is a medical practice that measures the shape, volume, length, area, height, concentration etc. of the human body in numerical figures to allow for the most subtle comparison, which was an important aspect of the physician's work that needed to be demonstrated, educated and transmitted to later generations to enable continuity of the medical profession.

• Korean Chemical Engineering Research
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• v.58 no.4
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• pp.573-580
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• 2020

Hydrogen emerged as a sustainable transport energy source. To increase hydrogen utilization, hydrogen refueling stations must be available in many places. However, this requires large-scale financial investment. This paper proposed a methodology for selecting the optimal location to maximize the use of hydrogen charging stations. The location of gas stations and natural gas charging stations, which are competing energy sources, was first considered, and the expected charging demand of hydrogen cars was calculated by further reflecting data such as population, number of registered vehicles, etc. Using k-medoids clustering, one of the machine learning techniques, the optimal location of hydrogen charging stations to meet demand was calculated. The applicability of the proposed method was illustrated in a numerical case of Seoul. Data-based methods, such as this methodology, could contribute to constructing efficient hydrogen economic systems by increasing the speed of hydrogen distribution in the future.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.363-367
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• 2016

A test section of a supersonic wind tunnel was designed for the analysis of flow characteristics over a backward-facing step with Mach 1.0 slot injection in a supersonic flow of Mach 2.5. The cavity flow of a high-speed vehicle is very complex at supersonic speed, so it is necessary to do experiments using supersonic wind tunnels to verify numerical analysis methods. The previous 2D symmetrical nozzle was replaced with an asymmetrical nozzle. The inviscid nozzle contour was designed using Method of Characteristics (MOC), and the boundary layer thickness correction was reflected by experimental data from the wind tunnel. The results were compared with a CFD analysis. The PID control system was changed to be based on the change of tank pressure. This improved the control efficiency, and the run times of supersonic flow increased by about 1 second. The flow characteristics over a backward facing step with slot injection were visualized by a Schlieren device. This equipment will be used for an experimental study of the film cooling effectiveness over a cavity with various velocities, mass flows, and temperatures.

• The KIPS Transactions:PartB
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• v.18B no.5
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• pp.271-278
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• 2011

Storm and flood such as torrential rains and major typhoons has often caused damages on a large scale in Korea and damages from storm and flood have been increasing by climate change and warming. Therefore, it is an essential work to maneuver preemptively against risks and damages from storm and flood by predicting the possibility and scale of the disaster. Generally the research on numerical model based on statistical methods, the KDF model of TCDIS developed by NIDP, for analyzing and predicting disaster risks and damages has been mainstreamed. In this paper, we introduced the model for prediction of damage cost from storm and flood by the neural network algorithm which outstandingly implements the pattern recognition. Also, we compared the performance of the neural network model with that of KDF model of TCDIS. We come to the conclusion that the robustness and accuracy of prediction of damage cost on TCDIS will increase by adapting the neural network model rather than the KDF model.

• Journal of the Korean Society for Railway
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• v.12 no.1
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• pp.129-134
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• 2009

To ensure the safety and functionality of a railroad bridge, maintaining the integrity of the bridge via continuous structural health monitoring is important. However, most structural integrity monitoring methods proposed to date are based on modal responses which require the extracting process and have limited availability. In this paper, the applicability of the existing damage identification method based on free-vibration reponses to time-domain deflection shapes due to moving train load is investigated. Since the proposed method directly utilizes the time-domain responses of the structure due to the moving vehicles, the extracting process for modal responses can be avoided, and the applicability of structural health evaluation can be enhanced. The feasibility of the presented method is verified via a numerical example of a simple plate girder bridge.

• Journal of Korean Society of Steel Construction
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• v.12 no.1 s.44
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• pp.45-54
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• 2000

Design-oriented approximate structural reanalysis models are compared and assessed, particularly with focus on the case of large changes of design variables. The effectiveness and reliability are demonstrated by means of numerical examples. The results of the study suggest the following conclusions relative to the potential of the procedures. (A) local approximation is only appropriate for the case of small changes in design : (B) global approximation is exact for the case of large changes in a small number of design variables, but inefficient : (C) local-global approximation is most effective and reliable for the case of large changes with a large number of design variables. These methods can improve the total efficiency when they are appropriately used to the design information for the redesign process of large scale structures.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.42 no.4
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• pp.183-193
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• 2019

Process mining is an analytical technique aimed at obtaining useful information about a process by extracting a process model from events log. However, most existing process models are deterministic because they do not include stochastic elements such as the occurrence probabilities or execution times of activities. Therefore, available information is limited, resulting in the limitations on analyzing and understanding the process. Furthermore, it is also important to develop an efficient methodology to discover the process model. Although genetic process mining algorithm is one of the methods that can handle data with noises, it has a limitation of large computation time when it is applied to data with large capacity. To resolve these issues, in this paper, we define a stochastic process tree and propose a tabu search-genetic process mining (TS-GPM) algorithm for a stochastic process tree. Specifically, we define a two-dimensional array as a chromosome to represent a stochastic process tree, fitness function, a procedure for generating stochastic process tree and a model trace as a string of activities generated from the process tree. Furthermore, by storing and comparing model traces with low fitness values in the tabu list, we can prevent duplicated searches for process trees with low fitness value being performed. In order to verify the performance of the proposed algorithm, we performed a numerical experiment by using two kinds of event log data used in the previous research. The results showed that the suggested TS-GPM algorithm outperformed the GPM algorithm in terms of fitness and computation time.

• Journal of the Society of Naval Architects of Korea
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• v.50 no.6
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• pp.458-465
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• 2013

Ship design engineering refers to the development and design of shipbuilding architectures in a drawing which reflects all relevant manufacturing processes. This paper provides analysis methods for model-information interfaces between hull structure design and outfitting design, and a technical application for manufacturing phases reflecting the pipe support pad and angle item automatically. The existing information procedure of pipe support pad and angle system processes information using drawing without model specification. Outfitting design team directly distributes drawings to the shop floor then manual-based marking and installation work are conducted refer to the distributed drawings. As a result, this process has become time consuming and causes problems in the productivity and quality improvement due to the rework caused by omitted or incorrect marking. The pipe support pad and angle marking is a method that automatically updates model information to hull structure design using sets of data that analyse the generated model in outfitting design processes. Therefore, this approach provides an efficient solution through design references without manual activities such as a reflection of hull structure design, cutting process, numerical control work, and dimension measurement and marking. The conversion of a method from the existing procedure based on manual marking to the reflective and automatic approach would have enabled to proceed installation work without manual activities for the measurement. Therefore, this research study proposes an efficient approach using pre-data analysis of model information interfaces between design and manufacturing phases to improve productivity during construction for shipbuilding.