• Proceedings of the KSR Conference
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• 2009.05b
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• pp.473-479
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• 2009

Dynamic analysis is necessary for the High-Speed Railway vehicle which aims to run on max 400km/h. Especially, dynamic simulation using CAE(Computer Aided Engineering) can help to reduce the time of development of the High-Speed Railway vehicles. Also, it helps to reduce prices and improve the quality such as safety, stability and ride. There are many dynamic software for a railway vehicle, such as Vampire and ADAMS-Rail. There are limitations for each software and difficulties to analyze overall dynamics for entire railway system. To overcome these limitations, in this study, a program which can simulate entire railway vehicles was developed. This program is easy to use because it was developed using C++, which is object-oriented programming language. In addition, the basic platform for the development of dynamic solver is prepared using the nodal, modal coordinate system with a wheel-rail contact module. Rigid, flexible and large deformable body systems can be modeled by a user according to the characteristic of a desired system. Its reliability is verified by comparison with a commercial analysis program.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.14 no.5
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• pp.141-151
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• 2004

According to the improvemnent of electronic commerce, the requirements of security devices are becoming increasingly pervasive. The security API must design easily and securely to support a compatibility feature between security devices. It is chosen the PKCS #11 interface by RSA Labs that shows the compatibility and extensibility standards of many application product and implementation, and supported KCDSA mechanism which is a korean digital signature standard. And the PKCS #11 security API defines new key management function which provides more secure key management ability. We suggest the object attributes and templates of KCDSA private and public key object, generate and verify digital signature using KCDSA mechanism. The PKCS #11 supporting KCDSA mechanism is designed, implemented using C-Language, tested a performance, and analyzed the security and compatibiltiy feature.

• Nutrition Research and Practice
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• v.17 no.6
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• pp.1255-1266
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• 2023

BACKGROUND/OBJECTIVES: This study aimed to predict the association between nutritional intake and diabetes mellitus (DM) by developing an artificial neural network (ANN) model for older adults. SUBJECTS/METHODS: Participants aged over 65 years from the 7th (2016-2018) Korea National Health and Nutrition Examination Survey were included. The diagnostic criteria of DM were set as output variables, while various nutritional intakes were set as input variables. An ANN model comprising one input layer with 16 nodes, one hidden layer with 12 nodes, and one output layer with one node was implemented in the MATLAB^® programming language. A sensitivity analysis was conducted to determine the relative importance of the input variables in predicting the output. RESULTS: Our DM-predicting neural network model exhibited relatively high accuracy (81.3%) with 11 nutrient inputs, namely, thiamin, carbohydrates, potassium, energy, cholesterol, sugar, vitamin A, riboflavin, protein, vitamin C, and fat. CONCLUSIONS: In this study, the neural network sensitivity analysis method based on nutrient intake demonstrated a relatively accurate classification and prediction of DM in the older population.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.12
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• pp.230-238
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• 1999

This paper describes a research work of developing computer-aided design of lead frame, semiconductor, with blanking operation which is very precise for progressive working. Approach to the system is based on the knowledge-based rules. Knowledge for the system is formulated from plasticity theories, experimental results and the empirical knowledge of field experts. This system has been written in AutoLISP on the AutoCAD using a personal computer and in I-DEAS Drafting Programming Language on the I-DEAS Master Series Drafting with Workstation, HP9000/715(64) and tool kit on the ESPRIT. Transference of data among AutoCAD, I-DEAS Master Series Drafting, and ESPRIT is accomplished by DXF(drawing exchange format) and IGES(initial graphics exchange specification) methods. This system is composed of six modules, which are input and shape treatment, production feasibility check, strip-layout, die-layout, modelling, and post-processor modules. The system can design process planning and Die design considering several factors and generate NC data automatically according to drawings of die-layout module. As forming process of high precision product and die design system using 2-D geometry recognition are integrated with technology of process planning, die design, and CAE analysis, standardization of die part in die design and process planning of high pression product for semiconductor lead frame is possible to set. Results carried out in each module will provide efficiencies to the designer and the manufacturer of lead frame, semiconductor.

• Journal of Computing Science and Engineering
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• v.11 no.4
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• pp.142-151
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• 2017

Spontaneous intracerebral hemorrhage (sICH) has a high mortality rate. Research has demonstrated that sICH occurrence is related to weather conditions; therefore, this study used the decision tree method to explore the impact of climatic risk factors on sICH at different ages. The Taiwan National Health Insurance Research Database (NHIRD) and other open-access data were used in this study. The inclusion criterion was a first-attack sICH. The decision tree algorithm and random forest were implemented in R programming language. We defined a high risk of sICH as more than the average number of cases daily, and the younger, middle-aged and older groups were calculated as having 0.77, 2.26 and 2.60 cases per day, respectively. In total, 22,684 sICH cases were included in this study; 3,102 patients were younger (<44 years, younger group), 9,089 were middle-aged (45-64 years, middle group), and 10,457 were older (>65 years, older group). The risk of sICH in the younger group was not correlated with temperature, wind speed or humidity. The middle group had two decision nodes: a higher risk if the maximum temperature was >$19^{\circ}C$ (probability = 63.7%), and if the maximum temperature was <$19^{\circ}C$ in addition to a wind speed <2.788 (m/s) (probability = 60.9%). The older group had a higher risk if the average temperature was >$23.933^{\circ}C$ (probability = 60.7%). This study demonstrated that the sICH incidence in the younger patients was not significantly correlated with weather factors; that in the middle-aged sICH patients was highly-correlated with the apparent temperature; and that in the older sICH patients was highly-correlated with the mean ambient temperature. "Warm" cold ambient temperatures resulted in a higher risk of sICH, especially in the older patients.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.2032-2033
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• 2007

There has been increasing interests of condition monitoring and diagnosis for electric equipment, which lead to the development of this system domestic and abroad. In the past, operators' interest was how to quickly repair and restore the electric equipments after failure. But, due to the North American Blackout in 2003 and the aging of equipments, users have paid attention to the condition based monitoring of electric equipment to prevent a fault like outrage. GIS-PDS("GIS Preventive and Diagnosis System") requiresa large amount of measurement data with timeliness for monitoring and analysis of real-time state of GIS(Gas Insulated Switchgear). We developed the timeliness-guaranteed communication device for GIS-PDS.

• International conference on construction engineering and project management
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• 2017.10a
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• pp.14-23
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• 2017

In high-density high-rise cities such as Hong Kong, buildings account for nearly 90% of energy consumption and 61% of carbon emissions. Therefore, it is important to study the design of buildings, especially high-rise buildings, to achieve lower carbon emissions in the city. The carbon emissions of a building consist of embodied carbon from the production of construction materials and operational carbon from energy consumption during daily operation (e.g., air-conditioning and lighting). An integrated analysis of both types of carbon emissions can strengthen the design of low carbon buildings, but most of the previous studies concentrated mainly on either embodied or operational carbon. Therefore, the primary objective of this study is to develop a holistic methodology framework considering both embodied and operational carbon, in order to enhance the sustainable design of low carbon high-rise buildings. The framework will be based on the building information modeling (BIM) technology because BIM can be integrated with simulation systems and digital models of different disciplines, thereby enabling a holistic design and assessment of low carbon buildings. Structural analysis program is first coupled with BIM to validate the structural performance of a building design. The amounts of construction materials and embodied carbon are then quantified by a BIM-based program using the Dynamo programming interface. Operational carbon is quantified by energy simulation software based on the green building extensible Markup Language (gbXML) file from BIM. Computational fluid dynamics (CFD) will be applied to analyze the ambient wind effect on indoor temperature and operational carbon. The BIM-based framework serves as a decision support tool to compare and explore more environmentally-sustainable design options to help reduce the carbon emissions in buildings.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.10 no.1
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• pp.85-94
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• 2017

In this paper, I proposed a sound model generation and a most frequent model search algorithm for recognizing animal vocalization. The sound model generation algorithm generates a optimal set of models through repeating processes such as the training process, the Viterbi Search process, and the most frequent model search process while adjusting HMM(Hidden Markov Model) structure to improve global recognition rate. The most frequent model search algorithm searches the list of models produced by Viterbi Search Algorithm for the most frequent model and makes it be the final decision of recognition process. It is implemented using MFCC(Mel Frequency Cepstral Coefficient) for the sound feature, HMM for the model, and C# programming language. To evaluate the algorithm, a set of animal sounds for 27 species were prepared and the experiment showed that the sound model generation algorithm generates 27 HMM models with 97.29 percent of recognition rate.

• Journal of the Korean Data and Information Science Society
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• v.21 no.1
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• pp.99-107
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• 2010

This research is for implementation of a software that can convert Hangul format file to $T_EX$ format file. Hangul is a word processor that has widely been used in Korea. It is known that Hangul is relatively easy of typing in equations and tables in preparing a paper draft. $T_EX$ has been developed as a computer programming language for preparing and publishing documents. Documents are first typed in with a plain text editor with $T_EX$ commands and then is compiled and linked. The software implemented in this research converts Hangul format files which are written under the specific format of a journal to $T_EX$ format file with the given style specific file. It converts special symbols, texts, tables, equations, and paragraph formats. We have used Hangul format of Journal of the Korean Data & Information Science Society (JKDISS) and the style file of $T_EX$ for the beta-test for the software.

• The Journal of the Korea Contents Association
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• v.16 no.1
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• pp.52-59
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• 2016

For almost of concrete structures by placing in cold weather, it is very important that the selection of curing method at early aged construction stage. The Exothermic curing method with hot wire and rapid hardening cement is used mostly to prevent the initial cracks and the strength decrease. Most of the construction sites, however, have not been applied to the optimal curing method caused by the simple approaches and the empirical judgements. Therefore, this paper has proposed a evaluation algorithm of the exothermic curing method for representing heating temperature, period, position of hot wire by analyzing the transient heat transfer solution. This has been implemented, moreover, using an object oriented programming language to develop structural analysis system taking account risk parameters. This system is composed of input module, database module, database store module, analysis module, and result generation module. Linkage interface between the central database and each of the related module is implemented by the visual c# concept. Graphic user interface and the relational database table are supported for user's convenience.