• Clean Technology
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• v.28 no.3
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• pp.203-209
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• 2022

An environmental evaluation was conducted by employing LCA methodology for a mechanical seal manufacturing process that uses recycled silicon recovered from end-of-cycle PV modules. The recycled silicon was purified and reacted with carbon to synthesize β-SiC particles. Then the particles underwent compression molding, calcination and heat treatment to produce a product. Field data were collected and the potential environmental impacts of each stage were calculated using the LCI DB of the Ministry of Environment. The assessment was based on 6 categories, which were abiotic resource depletion, acidification, eutrophication, global warming, ozone depletion and photochemical oxidant creation. The environmental impacts by category were 45 kg CO₂ for global warming and 2.23 kg C₂H₄ for photochemical oxide creation, and the overall environmental impact by photochemical oxide creation, resource depletion and global warming had a high contribution of 98.7% based on weighted analysis. The wet process of fine grinding and mixing the raw silicon and carbon, and SiC granulation were major factors that caused the environmental impacts. These impacts need to be reduced by converting to a dry process and using a system to recover and reuse the solvent emitted to the atmosphere. It was analyzed that the environmental impacts of resource depletion and global warming decreased by 53.9% and 60.7%, respectively, by recycling silicon from end-of-cycle PV modules. Weighted analysis showed that the overall environmental impact decreased by 27%, and the LCA analysis confirmed that recycling waste modules could be a major means of resource saving and realizing carbon neutrality.

• Proceedings of the Korean Society of Computer Information Conference
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• 2011.01a
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• pp.225-228
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• 2011

핸드폰에 의한 모바일 콘텐츠의 사용량이 날로 증가하고 있으며 이러한 추세에 맞추어 다양한 콘텐츠들이 다양한 플렛폼에서 생산되고 있다. 모바일 플랫폼에서 사용 가능한 콘텐츠 생산성은 플랫폼의 특수성으로 인해 생산 속도가 느리고 인력 투입이 많은 것이 문제점으로 지적되고 있다. 또한 무선 플랫폼에서 사용 가능한 콘텐츠 제작시 다양한 하드웨어 플랫폼으로 인한 액정 크기의 다양성과 사용 가능한 콘텐츠 개발 언어의 다양성으로 인한 문제점도 많은 것으로 알려져 있다. 본 연구에서는 이러한 생산성 저하의 원인으로 대표되는 문제점들과 다양한 하드웨어 플랫폼으로 인해 발생하는 문제점들을 해결하기 위한 모바일 콘텐츠를 통합 제작하고 테스트하는 PC용 소프트웨어를 개발하였다. xHTML 언어로 제작된 모바일 콘텐츠를 다양한 언어로 변환하기 위하여 패턴매칭 알고리즘을 사용한 변환 모듈을 개발하였다. 또한, 변환된 콘텐츠들을 각 플랫폼별로 테스팅 하기 위하여 개발자의 직접적 개입이 없이 모든 콘텐츠를 자동으로 검사하고 결과를 리포트 생성하는 자동 테스트 부분과 개발자의 육안으로 확인하고 테스트하여 결과 리포트를 생성하는 수동 테스트 부분으로 나누어진 소프트웨어 엔진을 개발하였다. 이상의 변환엔진을 사용하여 xHTML로 제작한 원본 콘텐츠는 다양한 플랫폼에서 이용 가능한 콘텐츠로 생산이 용이해 졌으며, 두 테스트 엔진을 사용하여 기본적인 콘텐츠 오류들을 쉽게 찾아내고 수정할 수 있는 개발 환경을 구축하였다.

• Journal of Welding and Joining
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• v.17 no.5
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• pp.61-68
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• 1999

For the last two decades, waveform control techniques have been successively developed and applied for the inverter welding machines resulting in the substantial reduction of spatter generated in CO₂ welding. One of the constituents commonly involved in those techniques is to delay the instant of current increase to some extent after the initiation of short-circuiting. Although this technique has been known to be quite effective in reducing the spatter generation through the suppression of is instantaneous short circuiting, the delay time necessary for minimum spatter has not been clearly understood. In this study, the control system for varying the delay time was constructed so that the spatter generation rates could be measured over a wide range of delay time, 0.29-2.0 msec. As a result of this study, it was demonstrated that spatter generation rate(SGR) sharply decreased at delay time of 0.6 msec and longer accompanied with the change in characteristics of short circuit mode from the instantaneous short-circuiting(ISC) dominant to normal short-circuiting(NSC) dominant. Another feature that have been found in current waveform of over 0.6msec was the creation of current pulse right after the arc reignition stage. Because of this current pulses weld pool oscillated in wave-like fashion and it looks like to play an important role in developing short circuiting between electrode and weld pool.

• Journal of Information Technology Services
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• v.8 no.1
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• pp.203-215
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• 2009

This paper illustrates the application of co-occurrence theory to generate lightweight ontologies semi-automatically. The proposed model includes three steps of a (Semi-) Automatic creation of Ontology; (they are conceptually named as) the Syntactic-based Ontology, the Semantic-based Ontology and the Ontology Refinement. Each of these three steps are designed to interactively work together, so as to generate Lightweight Ontologies. The Syntactic-based Ontology step includes generating Association words using co-occurrence in web documents. The Semantic-based Ontology step includes the Alignment large Association words with small Ontology, through the process of semantic relations by contextual terms. Finally, the Ontology Refinement step includes the domain expert to refine the lightweight Ontologies. We also conducted a case study to generate lightweight ontologies in specific domains(news domain). In this paper, we found two directions including (1) employment co-occurrence theory to generate Syntactic-based Ontology automatically and (2) Alignment large Association words with small Ontology to generate lightweight ontologies semi-automatically. So far as the design and the generation of big Ontology is concerned, the proposed research will offer useful implications to the researchers and practitioners so as to improve the research level to the commercial use.

• Journal of Korea Multimedia Society
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• v.24 no.11
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• pp.1538-1551
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• 2021

The current drone flight plan creation creates a flight path point of two-dimensional coordinates on the map and sets an arbitrary altitude value considering the altitude of the terrain and the possible flight altitude. If the created flight path is a simple terrain such as a mountain or field, or if the user is familiar with the terrain, setting the flight altitude will not be difficult. However, for drone flight in a city where buildings are dense, a safer and more precise flight path generation method is needed. In this study, using high-precision spatial information, we construct a drone safety flight map with a 3D grid map structure and propose a flight path search algorithm based on it. The safety of the flight path is checked through the virtual drone flight simulation extracted by searching for the flight path based on the 3D grid map created by setting weights on the properties of obstacles and terrain such as buildings.

• Journal of Korea Society of Industrial Information Systems
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• v.13 no.5
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• pp.22-28
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• 2008

This paper aims to offer a solution based on semantic document classification to improve e-Government utilization and efficiency for people using their own information retrieval system and linguistic expression. Generally, semantic document classification method is an approach that classifies documents based on the diverse relationships between keywords in a document without fully describing hierarchial concepts between keywords. Our approach considers the deep meanings within the context of the document and radically enhances the information retrieval performance. Concept Weight Document Classification(CoWDC) method, which goes beyond using existing keyword and simple thesaurus/ontology methods by fully considering the concept hierarchy of various concepts is proposed, experimented, and evaluated. With the recognition that in order to verify the superiority of the semantic retrieval technology through test results of the CoWDC and efficiently integrate it into the e-Government, creation of a thesaurus, management of the operating system, expansion of the knowledge base and improvements in search service and accuracy at the national level were needed.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.5
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• pp.83-92
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• 2015

Recently, Co-working that is a new trend of working and Co-working Space that create Co-working are increasing rapidly around the centers to support start-up such as one-person creative companies. However, the business centers located outside Seoul are not enough to recognize knowledge and skill for operating Co-working Space. Therefore, this study selects the big research issue which is "The recognition and case of co-working & application to co-working space" and the small research issue that is "Co-working Space operation activities" for qualitative research by using in-depth interview to managers of one-person creative company business centers. As a result, on the perspective of the big research issues, they understood Co-working concept, but the Co-working case was made by manager's effort without voluntary participation of the users. Co-working Space is important to recognize as a space for interaction and exchange information but was used only as a sharing space. And on the perspective of the small research issues, 'Space & Interior', 'Alliance and Partnership' and 'Community and Communication' show low awareness and activities. So, we suggest improvement plans through the case of best practices. This study is valuable, it could be a help to adapt and improve to Co-working Space in one-person creative company business center for creation of performance by Co-working.

• Journal of the Korea Institute of Military Science and Technology
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• v.27 no.5
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• pp.596-610
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• 2024

Since the creation of the first submarine telegraph cable connecting England and France in 1850, today, due to the rapid development of the Internet and Communications fields, the demand for submarine communication cables has increased and continues to develop. Submarine cables are designed and manufactured to be suitable for the maritime environment, and many parts are imported from overseas, and several domestic cable manufacturers are producing them for commercial purposes. Field-proven and reliable commercial submarine communication cable technology is also being applied to the military field, and is especially actively utilized in naval surface ships and submarines. This paper is about the design of an underwater cable applicable to submarine(KSS-III Bach-II) navigation radar and also is to secure the performance of an underwater cable with bending durability in extreme marine environments, emergency diving, and repeated mast raising and lowering. Finally, we hop that the domestic development of underwater cables will help improve the performance of navigation radars for submarines.

• Journal of the Korean Ceramic Society
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• v.49 no.3
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• pp.236-240
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• 2012

The reticulated carbon foam have been used for their excellent properties in terms of thermal management which is getting important in industrial field currently. In this study, we measure the mechanical properties of the reticulated carbon foam which is heat-treated at various temperature from the prepared low-density phenol foam. Simultaneously, we observe microstructures with high resolution transmission microscope and measure the residual oxygen content of carbon foams to figure out the relationship between the apparent change of properties such as weight loss and linear shrinkage during heat treatment. In conclusion, the carbon foam heat-treated at $1400^{\circ}C$ shows the highest strength, and the mechanical behavior is believed to be strongly related to the creation of nano-size graphite crystals from the amorphous carbon during heat treatment. On the other hand, it is turned out that the weight loss occurred at the temperature under $1400^{\circ}C$ comes from the elimination of oxygen in the form of $CO_2$ or CO, but no evidence is found on weight loss mechanism at the temperature above $1400^{\circ}C$.

• World Technopolis Review
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• v.5 no.1
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• pp.47-60
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• 2016

In today's digital non-linear global business environment, innovation initiatives are influenced by inter-organizational, political, economic, environmental, technological systems, as well as by decisions made individually by key actors in these systems. Network-based structures emerge from social linkages and collaborations among various actors, creating innovation ecosystems, complex adaptive systems in which entities co-create value. A shared vision of value co-creation allows people operating individually to arrive together at the same future. Yet, relationships are difficult to see, continually changing and challenging to manage. The Innovation Ecosystem Transformation Framework construct includes three core components to make innovation relationships visible and articulate networks of relational capital for the wellbeing, sustainability and business success of innovation ecosystems: data-driven visualizations, storytelling and shared vision. Access to data facilitates building evidence-based visualizations using relational data. This has dramatically altered the way leaders can use data-driven analysis to develop insights and provide ongoing feedback needed to orchestrate relational capital and build shared vision for high quality decisions about innovation. Enabled by a shared vision, relational capital can guide decisions that catalyze, support and sustain an ecosystemic milieu conducive to innovation for business growth.