• 대한기계학회논문집A
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• 제31권6호
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• pp.635-643
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• 2007

As many engineers and technicians are involved in the design process of large scale and/or complex products, there are a lot of miss matches and interferences due to designers' faults and several kinds of CAD systems. Recently, CAD systems are applied to verify and check the assembly process. Digital Mock-Up(DMU) system, a tool to build a virtual mock-up in the design stage, has been used to prevent the interferences and miss matches during precision design processes. Using the virtual assembly tool, engineers are able to design precision and interference free parts without physical mock-ups. Instead of a single CAD source, several CAD systems are used to design a complex product. Several organizations are involved in the distributed design environment for heterogeneous multi-CAD assembly. XML and the lightweight CAD file are proposed for the multi-CAD assembly. XML data contains hierarchy of the heterogenenous multi-CAD assembly. STEP PDM schema and STEP ISO 10303-28 formations are applied to construct the XML data. The lightweight CAD file produced from various CAD files through ACIS kernel and InterOp not only contains mesn, B-Rep and topological data, but also is used to visualize CAD data and to verify dimensions. Developed system is executed on the desktop computers. It does not require commercial CAD systems to visualize 3D assembly data. Real-time interference and fitness checks, dimensional verification, and design and assembly verification are performed on the developed system. Assembly of heterogeneous models for a car is conducted to verify the effectiveness of the developed DMU system on the Internet.

• 정보처리학회논문지D
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• 제9D권6호
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• pp.971-980
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• 2002

최근 지식경영의 중요성이 부각됨에 따라 데이터웨어하우징에 대한 관심이 집중되고 있다. 특히 온라인 분석 처리(On-Line Analytical Processing : OLAP) 시스템은 데이터 데이터하우징의 효과적인 활용 방안으로 많은 종류의 OLAP 제품들이 공급되어 왔다. 그러나 OLAP 기술은 실제로 아무런 표준 없이 매우 오랫동안 사용되어 왔으며, 이러한 다양성은 여러 OLAP 제품들 간에 데이터 교환과 인터페이스를 매우 어렵게 했다. 이에 본 논문에서는 서로 다른 OLAP 제품들간에 공통적으로 사용할 수 있는 OLAP 메타데이터 교환 모델을 설계하고, 그 메타데이터를 기반으로 생성된 큐브들을 교환할 수 있도록 하는 OLAP 메타데이터 교환 시스템을 구현하였다. OLAP 메타데이터 교환 모델의 설계는 XML을 사용하였고, 시스템의 사용자 인터페이스는 웹기반으로서 여러 OLAP 제품들과 메타데이터를 주고받을 수 있는 환경을 제공하였다. 사용자는 OLAP 제품들의 복잡한 큐브 생성 과정을 특별히 습득할 필요가 없으며, 하나의 큐브로 여러 제품들이 제공하는 서로 다른 분석 환경을 경험할 수 있다. 본 연구를 확장하여 OLAP 제품들이 공통으로 사용될 수 있는 질의 언어를 설계하고 적용 할 수 있다면 OLAP 제품들간의 원활한 의사소통이 이루어질 수 있을 것으로 전망한다.

• 한국신뢰성학회지:신뢰성응용연구
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• 제9권4호
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• pp.351-362
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• 2009

This paper describes the issues that must be considered for the diagnosis and improvement of home network systems during the product development phase, and what must be done to resolve the reliability problem when a system is about to enter the Japanese market. It suggests that after the product specifications are determined, an accurate analysis of the environment is needed, and should include factors such as the temperature, humidity and power source of the country concerned. Furthermore, the video standards, residential complex installation environment, wiring specifications, and approval standards must be considered. All the above processes are described in this paper through the case study. The purpose of this paper is that suggested procedures in this research is to be used as a reference for developing similar products in the future.

• 한국가스학회지
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• 제23권2호
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• pp.28-34
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• 2019

현재 울산국가산업단지에는 생산량의 증대와 이송의 편의를 위해 막대한 규모의 지하매설배관이 설치되어 있다. 현재 울산국가산업단지에는 62개 사에 총 1,293km의 지하배관이 설치되어 있으며, 이 중에서 상당수는 사업장 외부에 설치되어 있다. 최근 3년간 울산국가산업단지에서는 5건의 누출사고가 발생하였으며, 대응시간은 평균 8시간 이상 걸렸다. 이러한 사고대응의 지체는 심각한 2차 사고로 이어질 수 있으며, 이는 지역주민들에게 큰 위험을 줄 수도 있다. 본 연구에서는 지하매설배관에 긴급차단장치를 설치하는 경우 사고영향평가를 통해 얼마나 누출사고의 영향이 경감되는지 분석하였다. 본 연구의 결과를 통해 긴급차단장치 설치가 지하매설배관의 누출사고의 피해를 줄이는 데 큰 역할을 할 수 있음을 검증하였다. 향후, 지하매설배관의 안전성 향상을 위해 시급히 긴급차단장치의 설치를 입법화하고 실행되어야 할 것이다.

• 대한산업공학회지
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• 제29권2호
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• pp.157-164
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• 2003

The amount of information increases rapidly when working in a distributed environment where multiple collaborative partners work together on a complex product. Today's PDM (product data management) systems provide good capabilities regarding the management of product data within a single company. However, taking into account the variety of systems used at partner sites in an engineering environment one can easily imagine problems regarding the interoperability and the data consistency. This paper presents a concept to improve the workflow management using the parameters network. It shows a parameter driven engineering workflow that is able to manage engineering task across company boarders. We introduce a mechanism of workflow management based on the engineering parameters and an architecture of the distributed workspace to apply it within a PDM system. For a parameter mapping between CAD and PDM system we developed an XML-based CATIA data interface module using CAA.

• 제어로봇시스템학회논문지
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• 제9권4호
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• pp.340-346
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• 2003

Driven by the growth of the Internet and the increasing ubiquity of embedded computing systems, the embedded system is exploding in terms of it proliferation of products and the number of complex applications. Intelligent dedicated systems and appliances used in interface, monitoring, communications, and control applications increasingly demand the services of a sophisticated, state-of-the-art operating system. In the case of industrial controller, it is required to use a real-time operating system (RTOS) as a good building block to enable Internet connectivity. However, commercial RTOSes are increasingly less desirable due to their lack of standardization and their inability to keep pace with the rapid evolution of technology. In order to overcome these problems, we consider using embedded Linux and embedded web server. Availability of source code, reduced licensing, reliability, open source community support, as well as others, are key reasons for the use of embedded linux by embedded developers. In this paper, we develop embedded linux platform to control the industrial inverter with the Internet connecting feature. The method of web-based management is also proposed by using the embedded web server and Java applet. We show the feasibility of remote management for the commercial inverter controller with the proposed three-tier web-based remote management system.

• 대한안전경영과학회지
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• 제17권1호
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• pp.93-101
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• 2015

The demand from customers on better products and systems seems to be ever increasing. To meet the demand, the systems are becoming more and more complicated in terms of both scale and functionality, thereby requiring enormous effort in the development. One bright spot of this trend is that such effort has been the driving forces of the remarkable advancement in modern systems development. On the other hand, safety issues appear to be critical in many large-scale systems such as transportation and weapon systems including high-speed trains, airplanes, ships, missiles/rockets launchers, and so on. Such systems turn out to be prone to a variety of faults and thus the resultant failure can cause disastrous accidents. For the reason, they can be referred to as safety-critical systems. The systems failure can be attributed to either random or systemic factors (or sometimes both). The objective of this paper is on how to reduce potential systemic failure in safety critical systems. To do so, a proper system design is pursued to minimize the risk of systemic failure. A focus is placed on the fact that complex systems have a lot of complicated interfaces among the system elements. To effectively handle the sources of hazards at the complicated interfaces and resultant failure, a method is developed by utilizing a design structure matrix. As a case study, the developed method is applied in the design of train control systems.

• Journal of Microbiology and Biotechnology
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• 제31권8호
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• pp.1123-1133
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• 2021

Biodegradation is the key process involved in natural lignocellulose biotransformation and utilization. Microbial consortia represent promising candidates for applications in lignocellulose conversion strategies for biofuel production; however, cooperation among the enzymes and the labor division of microbes in the microbial consortia remains unclear. In this study, metagenomic analysis was performed to reveal the community structure and extremozyme systems of a lignocellulolytic microbial consortium, TMC7. The taxonomic affiliation of TMC7 metagenome included members of the genera Ruminiclostridium (42.85%), Thermoanaerobacterium (18.41%), Geobacillus (10.44%), unclassified_f__Bacillaceae (7.48%), Aeribacillus (2.65%), Symbiobacterium (2.47%), Desulfotomaculum (2.33%), Caldibacillus (1.56%), Clostridium (1.26%), and others (10.55%). The carbohydrate-active enzyme annotation revealed that TMC7 encoded a broad array of enzymes responsible for cellulose and hemicellulose degradation. Ten glycoside hydrolases (GHs) endoglucanase, 4 GHs exoglucanase, and 6 GHs β-glucosidase were identified for cellulose degradation; 6 GHs endo-β-1,4-xylanase, 9 GHs β-xylosidase, and 3 GHs β-mannanase were identified for degradation of the hemicellulose main chain; 6 GHs arabinofuranosidase, 2 GHs α-mannosidase, 11 GHs galactosidase, 3 GHs α-rhamnosidase, and 4 GHs α-fucosidase were identified as xylan debranching enzymes. Furthermore, by introducing a factor named as the contribution coefficient, we found that Ruminiclostridium and Thermoanaerobacterium may be the dominant contributors, whereas Symbiobacterium and Desulfotomaculum may serve as "sugar cheaters" in lignocellulose degradation by TMC7. Our findings provide mechanistic profiles of an array of enzymes that degrade complex lignocellulosic biomass in the microbial consortium TMC7 and provide a promising approach for studying the potential contribution of microbes in microbial consortia.

• 대한안전경영과학회지
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• 제15권3호
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• pp.7-17
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• 2013

The recent trend in modern systems development can be characterized by the increasing complexity in terms of both the functionality and HW/SW scale that seems to be accelerated by the growing user requirements and the rapid advancement of technology. Among the issues of complexity, the one related to systems safety has attracted great deal of attention lately in the development of the products ranging from mass-transportation systems to defence weapon systems. As such, the incorporation of safety requirements in systems development is becoming more important. Note, however, that since such safety-critical systems are usually complex to develop, a lot of organizations and thus, engineers should participate in the development. In general, there seems to be a variety of differences in both the breadth and depth of the technical background they own. To address the problems, at first this paper presents an effective design process for safety-critical systems, which is intended to meet both the systems design and safety requirements. The result is then advanced to obtain the models utilizing the systems modeling language (SysML) that is a de facto industry standard. The use of SysML can facilitate the construction of the integrated process and also foster active communication among many participants of diverse technical backgrounds. As a case study, the model-based development of high-speed trains is discussed.

• 한국식품영양과학회지
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• 제22권2호
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• pp.246-252
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• 1993

Melanoidins, as brown colored polymers, are formed through the diversified reaction systems of Maillard type and other reactions. Melanoidins are important components in relation to food quality and also are known to have antioxidative, mutagenic and antimutagenic activities. Since these aspects have been extensively reviwed elsewhere, only the recent studies regarding to their antioxidative and antimutagenic activities are discussed in this review. Even though their mechanisms are not clearly identified, melanoidins or specific fractions isolated from their mixtures have shown varied antioxidative activities depending on the reaction systems and reaction conditions. Those activities presumely are derived from the complex functional properties of hydrogen / electron donors and metal chelating power, which are originated from their reductone structure and others. It is considered that pyrolysate and other mutagens are formed by the given conditions in some cases during browning reaction, whereas melanoidins and their fractions have antimutagenic effects on chemical and other mutagens. There are positive correlationship among the color intensity, antioxidative activity and antimutagenicity of melanoidins or their fractions. These suggest that the antimutagenicity of melanoidins could be attributed to their antioxidative properties, however, it might also be due to other factors, because the relevant responses for antimutagenicity are very complicate and not clear. Accordingly, further studies are required to determine the actual acitivities and mechanisms involved in antioxidation and (anti)mutagenicity of melanoidins by reaction systems / conditions and by the isolated fractions. And also, additional studies are needed to evaluate the applications of melanoidins and their relevant effects to food and human health.