• Journal of Aerospace System Engineering
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• v.18 no.2
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• pp.12-20
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• 2024

The application of reinforcement design to ensure the structural safety of electronics in small satellites is limited by the spatial constraints of the satellite structure during launch vibrations. Additionally, a reliable evaluation approach is needed for mounting highly integrated devices that are susceptible to fatigue failure. Although the Steinberg fatigue failure theory has been used to assess the structural integrity of electronic devices, recent studies have highlighted its theoretical limitations. In this paper, we propose a structural methodology based on the critical strain theory to design the digital control unit (DCU) of the X-band SAR payload component for the small SAR technology experimental project (S-STEP), a small satellite constellation. To validate the design, we conducted modal and random analyses using simplified modeling techniques. Based on our methodology, we ultimately demonstrated the structural safety of the electronics through analysis results, safety margin derivation, and functional tests conducted both before and after the launch test.

• Perspectives in Nursing Science
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• v.5 no.1
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• pp.17-31
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• 2008

Purpose: The purpose of this study was to evaluate the usability of a prototype personal digital assistant (PDA)-based decision support system for the management of obesity through usability testing with end-users (Advanced Practice Nurses [APNs]) prior to its implementation in clinical settings. Methods: This descriptive study used observational and think aloud techniques to address the research question: what usability problems are perceived by end-users? Five APNs were provided with the scenarios and the list of tasks to evaluate the application. Their verbalizations were recorded through Morae usabil ity software. Data analysis was based on the data captured through Morae, transcriptions, notes, and the end-user survey. Results: End-users completed all the required tasks without encountering a severe usability problem, and agreed that the system was easy to use. clear, concise, and useful. Usability issues that were unrecognized by the developer or usability experts were identified by APNs. The usability problems were categorized according to positive characteristics, negative characteristics, and recommendations. The usability issues were discussed with the project team members, and solutions were suggested to improve the user interface of the PDA-based decision support system before the final implementation. Conclusions: This approach had an important impact on making the system easier to use and more useful from the perspective of design and content. The results of this evaluation provided iterative feedback regarding the design and implementation of the PDA-based decision support system for the management of obesity.

• Journal of Construction Engineering and Project Management
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• v.1 no.2
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• pp.11-17
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• 2011

Recent demands from construction industry have emphasized the capability for graduates to have improved skills both technical and non-technical such as problem solving, interpersonal communication. To satisfy these demands, problem-based learning that is an instructional method characterized by the use of real world problem has been adopted and has proven its effectiveness various disciplines. However, in spite of the importance of field senses and dealing with real problem, construction engineering education has generally focused on traditional lecture-oriented course. In order to improve limitations of current construction education and to satisfy recent demands from construction industry, this paper proposes a new educational approach that is Failure-Based Learning for using combination of the procedural characteristics of the problem-based learning theory in construction technology education utilizing failure information that has the educational value in the construction area by reinterpreting characteristics of construction industry and construction failure information. The major results of this study are summarized as follows. 1) Educational effect of problem-based learning methodology and limitation of application in construction area 2) The educational value of the information on construction failure and limitation in application of the information in construction sector 3) Anticipated effect from application of the failure-based learning 4) Development and application of the failure-based learning conceptual model.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1995.04a
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• pp.891-895
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• 1995

This paper describes a solid modeling system based on a systematic description of techniques for analyzing and understanding on engineering drawings. Main stress is placed on clarifying the difference between the drawing understanding and the drawing recognition. The former, in which we feel major interest, is intrinsically a difficult problem because it inherent contains combinatorial search to require more than polynomial time. Actually, understanding drawings is regarded as a process to recover the information lost in projection 3-D objects to 2-D drawings. But, solid modeling by automatic understanding of the given drawings is one of the promising approach, which is described precisely in the text. Reviewing the studies performed so far, we summarize the future direction of the project and inevitable open problems left.

• International Journal of Contents
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• v.7 no.4
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• pp.64-69
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• 2011

Recently, as smart devices are distributed more and more, the need for education of developing contents based on smart media increases. In order to develop contents based on smart media, it is necessary to learn new programming language as well as to understand the structure of platforms as device-manufacturers and communication companies have different platforms. Generally, the problem in education of programming is that it can provide learning to understand the language stage by stage, but it is difficult to suggest a clear result such as completion of learner's project from macroscopic and integrated approach. Especially, there is a difficult of learning several programming languages due to the characteristics of platforms in developing smart contents. Accordingly, in the education of programming for developing smart contents, it is not appropriate to use the traditional teaching method of programming which conducts projects from an integrated point of view after learning the grammatical elements of the language. This paper aims to suggest the top-down teaching method as an effective teaching method for developing contents based on smart media, and to analyze the effect after developing and applying the suggested teaching model.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 1997.11a
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• pp.423-438
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• 1997

Today's building and fire prevention codes are mostly prescriptive. Prescriptive codes are based on major fires in earlier years that created a need for specific building provision. These codes provide a minimum level of safety. As the general and engineering uses of computers have increased over the years, so has use of computers in the fire protection engineering. This has allowed fire protection engineers to develop alternative approaches to solve today's fire protection problems or to evaluate the performance of a specific fire safety goal. A performance based approach to building and fire codes involves the following: 1) identifying specific goals, such as, safely getting out of the building in 10 minutes, 2) obtain conceptual approval from authorities, 3) define performance level, 4) develop design solutions and identify tools such as, fire tests, models, or methods, to demonstrate that a design will meet the fire protection objective 5) test solutions, 6) present test method and results to the authorities. Some people in the fire protection community consider this to be nothing more than an intellectual exercise, while the others view it as a way to reduce expenses on large project$^4$ Others in fire protection community view this as a way to refine the design process to design fire protection systems to better protect the fire hazards. This paper will focus on application of these tools, specifically computer fire models, to actual cases such as: design of a smoke control system heat transfer analysis and egress of building occupants during potential fires.

• Journal of KIISE:Software and Applications
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• v.30 no.12
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• pp.1193-1207
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• 2003

Various web applications are developed as the Internet is popularized in many fields. However, in most cases of web application development, systematic analysis is omitted and developers jump into the implementation. Therefore developers have difficulties with applying the development methods for a large scale project. The approach of creating an analysis models of a web application from a business model is proposed for the rapid and efficient development. The analysis process, tasks and techniques are proposed for this approach. The use case diagram and web page list are created from business modes that is depicted using the notation of UML activity diagram. The page diagram and logical / physical database models are created using the use case diagram and the web page list. These analysis models are refined during the detailed design phase. The efficiency of proposed method has been shown using a practical case study which reflects the development project of the web application for supporting the association of auto repair shops.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.375-385
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• 2013

As climate change and environmental pollution become one of the biggest global issues today, new renewable energy, especially solar photovoltaic (PV) system, is getting great attention as a sustainable energy source. However, initial investment cost of PV system is considerable, and thus, it is crucial to predict electricity generation accurately before installation of the system. This study analyzes the loss ratio of solar photovoltaic electricity generation from the actual PV system monitoring data to predict electricity generation more accurately in advance. This study is carried out with the following five steps: (i) Data collection of actual electricity generation from PV system and the related information; (ii) Calculation of simulation-based electricity generation; (iii) Comparative analysis between actual electricity generation and simulation-based electricity generation based on the seasonality; (iv) Stochastic approach by defining probability distribution of loss ratio between actual electricity generation and simulation-based electricity generation ; and (v) Case study by conducting Monte-Carlo Simulation (MCS) based on the probability distribution function of loss ratio. The results of this study could be used (i) to estimate electricity generation from PV system more accurately before installation of the system, (ii) to establish the optimal maintenance strategy for the different application fields and the different season, and (iii) to conduct feasibility study on investment at the level of life cycle.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1107-1112
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• 2009

To design and build a deformed building, new approaches and technologies are required, in which a design approach with parametric and generative technology is used for design and for building it, computer based fabrication technology. Even if parametric design technology is not a state of the art thing, the technology is still used widely, in order to effect the efficiency and furthermore it will continue to be innovated upon continuously. To cope with the limitation of it, the generative design system is developed. Deformed building design requires new methodology to overcome the limitations of conventional ways, which have difficulties to create enough design alternatives to explore satisfied design solutions order to deformed design have geometrical complexity and dramatically increased amount of data. Hence the generative design system can be a cutting edge methodology to solve it. However we should consider how to build the design in the real world. For this, the computer based fabrication technology which is used in mechanical industry is required to introduce to architecture and construction domain for efficiency. In this research, the methodology is modeled and tested with Bezier surface based shell structure.

• Journal of Korean Society for Atmospheric Environment
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• v.34 no.2
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• pp.342-355
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• 2018

Emission inventory (EI) is often recognized as a foundational pillar for air quality planning. In this manuscript, we reviewed national emission inventory (NEI) development processes in United States(US) and made recommendations for South Korean emission inventory development for the future. First, we examined history of emission inventory development in US while focusing on what has been success and failure. We noticed that, in general, emission reductions led to air pollution abatement although efficacy of same degree of reduction may not result in similar air quality improvement. Second, we described conventional approaches of developing NEI and differences between NEI and EI for State Implementation Plan which is required for air quality management in US. Last, we analyzed how US Environmental Protection Agency and counterpart agencies in states came up with a new plan for the next major regulatory modeling project. Based on our analysis, we conclude that early and steady participation of local governments will lead to effective and efficient emission inventory development and, in turn, will result in successful air quality planning that is necessary for actual air quality improvement.