• Proceedings of the KSME Conference
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• 2000.04a
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• pp.714-719
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• 2000

In this paper, an application program is made to simulate the behavior of a ship block under various crane works and to generate data of lu9 reactions and wire tensions. The program is based on a CAD program, Pro/ENGINEER. A ship is composed of more than 100 ship blocks. In order to lift, move, turn, or put a ship block at a convenient location fur assembling, workers in a shipyard use cranes, wires, and lugs temporarily attached to the block. In the procedure of lifting and turning a ship block with a crane, it is important to find suitable lug points and wires to do the handling efficiently and prevent accidents. Evaluation of forces in lugs and wires is necessary, but the problem is rather complex due to nonlinearity and nonuniqueness. In the present development, the nonlinear system of equations for quasi-static equilibriums is derived and a Newton type solution method is adopted to solve the system. The importance of initial estimates to the solution is illustrated and two approaches are utilized and compared. With the program developed, users can assign lug points on the CAD model by mouse and choose various linking devices at each crane point. Users can try to simulate the motion for any prescribed conditions, compare the motion of the block and the reactions and choose appropriate lug points and the type of wires and lugs.

• Structural Engineering and Mechanics
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• v.57 no.5
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• pp.937-949
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• 2016

Fiber reinforced polymer (FRP) applications in the structural engineering field include concrete-FRP composite systems, where FRP components are either attached to or embedded into concrete structures to improve their structural performance. This paper presents the results of an analytical study conducted using finite element model (FEM) to simulate the behavior of three-points load beam reinforced with GFRP and/or steel bars. To calibrate the FEM, a small-scale experimental program was carried out using six reinforced concrete beams with $200{\times}200mm$ cross section and 1000 mm length cast and tested under three point bending load. The six beams were divided into three groups, each group contained two beams. The first group was a reference beams which was cast without any reinforcement, the second group concrete beams was reinforced using GFRP, and the third group concrete beams was reinforced with steel bars. Nonlinear finite element simulations were executed using ANSYS software package. The difference between the theoretical and experimental results of beams vertical deflection and beams crack shapes were within acceptable degree of accuracy. Parametric study using the calibrated model was carried out to evaluate two parameters (1) effect of number and position of longitudinal main bars on beam behavior; (2) performance of concrete beam with composite longitudinal reinforcement steel and GFRP bars.

• Journal of KIISE:Software and Applications
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• v.27 no.1
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• pp.13-23
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• 2000

As software becomes more complicated and large-scaled, user's demands become more varied and his expectation levels about software products are raised. Therefore it is very important that a software engineer analyzes user's requirements precisely and applies it effectively in the development step. This paper presents a requirements analysis system that reduces and revises errors of requirements specifications analysis effectively. As this system measures the similarity among requirements documents and sentences, it assists users in analyzing the dependency among requirements specifications and finding the traceability, redundancy, inconsistency and incompleteness among requirements sentences. It also extracts sentences that contain ambiguous words. Indexing method for the similarity measurement combines sliding window model and dependency structure model. This method can complement each model's weeknesses. This paper verifies the efficiency of similarity measure techniques through experiments and presents a proccess of the requirements specifications analysis using the embodied system.

• The KIPS Transactions:PartD
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• v.15D no.3
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• pp.321-326
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• 2008

The software defects that are not found in the course of a project frequently appear during the conduct of the maintenance procedure after the complete development of the software. As the frequency of surfacing of defects during the maintenance procedure increases, the cost likewise increases, and the quality and customer reliability decreases. The defect rate will go down only if cause analysis and process improvement are constantly performed. This study embodies the defect tracking system (DTS) by considering the Pareto principle: that most defects are repetitions of defects that have previously occurred. Based on the records of previously occurring defects found during the conduct of a maintenance procedure, DTS tracks the causes of the software defects and provides the developer, operator, and maintenance engineer with the basic data for the improvement of the software concerned so that the defect will no longer be manifested or repeated. The basic function of DTS is to analyze the defect type, provide the measurement index for it, and aggregate the program defect type. Doing these will pave the way for the full correction of all the defects of a software as it will enable the defect correction team to check the measured defect type. When DTS was applied in the software configuration management system of the W company, around 65% of all its software defects were corrected.

• Journal of the Korean Society of Safety
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• v.37 no.4
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• pp.28-35
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• 2022

This study is aimed to develop a safety diagnosis system for fire pumps that detects normal and abnormal signals for the stable operation of the system. Hence, the following activities were carried out: first, a threshold value was identified for the normal operation and six abnormal operations (adherence of impeller, absence of water source, separation of pump and motor, run-stop operation, air inflow into the casing, and reverse-phase loss of the power line) reflecting changes in the current, flow and pressure of fire pumps; secondly, based on the identified signals, an algorithm capable of detecting three abnormal signals was developed and in terms of hardware, a current, pressure and flow sensor suitable for the analogue input values of NI-6009 was designed and installed. This combination of the hardware and software is applicable as a diagnosis system to ensure the stable operation of fire pumps.

• Industry Promotion Research
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• v.8 no.2
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• pp.37-43
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• 2023

Sampling In this study, we examined the problems and their improvement plans associated with the reliability management sector in quality management engineer test conducted in Korea. First of all, there seems to be a problem in that the terminology is not unified and some techniques essential for reliability analysis are not included. We also looked at quality and reliability tests performed in foreign countries (especially USA) that Koreans often acquire. In particular, it can be seen that the CRE test almost overlaps with the contents of the reliability management engineer test in Korea. However, while the USA is an open book test, Korea is not, so the problem is that there are too many formulas to memorize on the part of the test takers. In addition, the analysis of the data is done manually without using computer software. If the test were an open book test like the CRE test in USA, it will be a test that can go beyond fragmentary knowledge and check whether test takers have the essential elements in reliability management. Lastly, if we adopt re-certification system through education and work within a certain period of time, as in USA, it will be a qualification test suitable for modern people living in a flood of information.

• Journal of KIISE:Software and Applications
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• v.27 no.4
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• pp.384-392
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• 2000

As a software becomes more complicated and large-scaled, it is very important for a software engineer to analyze user's requirements precisely and apply them effectively in the development stage. Due to the growth of the internet, the necessity of requirements elicitation and analysis in distributed environments has also become larger. This paper proposes a requirements elicitation supporting system that offer the basis for effectively analyzing requirements collected in distributed environments. The proposed system automatically categorizes collected requirements sentences into selected subject fields by measuring their similarity using a similarity measurement technique. Therefore, it reduces the difficulties in the initial stage of requirements analysis and it supports rapid and correct requirements analysis. This paper verifies the efficiency of the proposed system in similarity measurement techniques through experiments, and presents a process for requirements specifications elicitation using the embodied system

• Journal of Platform Technology
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• v.8 no.4
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• pp.47-58
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• 2020

DO-330 Software Tool Qualification Considerations is a guideline for development of tools used to develop/verify software and hardware installed on aircraft. And among several processes, the verification process is very crucial as it occupies a large proportion for DO-330. Especially, in order to qualify tool with high safety level, test objectives must be performed with independence, accordingly, more time, cost, and manpower are required than other objectives. In addition, even if the test cases or test procedures are well defined, the higher the complexity of the test the higher probability of human error occurs. In this paper, we propose Script-based Test Automation Agent software structure for efficient DO-330 verification process of A661UAGEN tool developed by Hanwha Systems. Compared to the test performed manually by the test engineer, testing time of the Script-based Test Automation Agent is reduced by 87.5% and testing productivity is increased by 43.75%.

• Journal of The Korean Digital Architecture Interior Association
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• v.11 no.1
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• pp.83-90
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• 2011

Lighting simulation is becoming increasingly more important as a method for design and evaluation. There is a wide range of packages that provide the accuracy and the usability in lighting simulation. Relux developed by Relux Informatik AG, Switzerland, Relux offers users innovative and high-performance light planning software with open interfaces and simultaneous access to the latest product data from luminaire and lamp manufacturers. The goals of this report is to explore some of the lighting simulation issues relating to Relux. It is hoped that it will provide some background information that will enable a designer and engineer to make some informed judgements on the potential of the current state-of-the-art in computer prediction of lighting in buildings and how this may be used to assist in building design.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.114-117
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• 2005

An expert system is a system that employs human knowledge captured in a computer to solve problem that ordinarily require human expertise. Well-designed expert systems imitate the reasoning processes experts use to solve specific problem. Specially, expert systems are used to the engineer in manufacturing industry for the process control, production management and system management. In this paper, we propose the design process expert system for product design process in manufacturing industry and we present introduction and contents of design process expert system methodology and software for the air purifier design system. This system will be helpful to improvement of design process for the air purifier production.