• Korean Journal of Artificial Intelligence
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• v.6 no.1
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• pp.1-10
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• 2018

Compressed Air is an important energy source used in most factories nowadays. The automation trend using air compressor has been gradually increasing with the interest of the 4th industry in recent years. With the air compressor system, it is possible to construct the device at low cost and easily achieve automation and energy saving. In addition, With trend of FA, miniaturation and light weight manufacturing trend expand their use in the electronics, medical, and food sectors. Research method is to design the technology for the remote control of the following information as USN base. Development of flexible sensing module from real time observation module for fusion of IT technology in compressed air systems, design and manufacture of flexible sensing module, and realiability assessment. Design of real-time integrated management system for observation data of compressed air system - Ability to process observation data measured in real time into pre-processing and analysis data. This study expects unconventionally decreasing effect of energy cost that takes up 60~70% of air compressor layout and operation and maintenance management cost through USN(Ubiquitous Sensor Network) technology by using optimum operational condition from real time observation module. In addition, by preventing maintenance cost from malfunction of air compressor beforehand, maintenance cost is anticipated to cut back.

• Structural Engineering and Mechanics
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• v.30 no.2
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• pp.135-146
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• 2008

This study utilizes the fine-tuning and small-digit characteristics of the successive zooming genetic algorithm (SZGA) to propose a method of structural damage detection in a continuum structure, where the differences in the natural frequencies of a structure obtained by experiment and FEM are compared and minimized using an assumed location and extent of structural damage. The final methodology applied to the structural damage detection is a kind of pseudo-discrete-variable-algorithm that counts the soundness variables as one (perfectly sound) if they are above a certain standard, such as 0.99. This methodology is based on the fact that most well-designed structures exhibit failures at some critical point due to manufacturing error, while the remaining region is free of damage. Thus, damage of 1% (depending on the given standard) or less can be neglected, and the search concentrated on finding more serious failures. It is shown that the proposed method can find out the exact structural damage of the monitored structure and reduce the time and amount of computation.

• Composites Research
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• v.36 no.4
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• pp.264-269
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• 2023

Spent coffee grounds (SCG) are a ubiquitous byproduct of coffee consumption, representing a significant waste management challenge, as well as an untapped resource for economic development and sustainability. Improper disposal of SCG can result in environmental problems such as methane emissions and leachate production. This study aims to investigate the physicochemical properties of SCG and their potential as a reinforcement material in polypropylene (PP) to fabricate an eco-friendly composite via extrusion and injection molding, with SCG filler ratios ranging from 5-20%. To evaluate the effect of SCG on the morphological and mechanical properties of the bio- composite, thermogravimetric analysis, SEM, tensile, flexural, and impact tests were conducted. The results demonstrated that the addition of SCG lead to a slight increase in brittleness of the composite but did not significantly affect its mechanical properties. Impressively, the presence of a significant organic component in SCG contributed to the enhanced thermal performance of PP/SCG composites. This improvement was evident in terms of increased thermal stability, delayed onset of degradation, and higher maximum degradation temperature as compared to pure PP. These findings suggest that SCG has potential as a filler material for PP composites, with the ability to enhance the material's properties without compromising overall performance.

• Information Systems Review
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• v.6 no.2
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• pp.79-94
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• 2004

The Internet is now an ubiquitous technology in business and possesses the potential to make the concept of value chain into an attainable reality. We posit that the way the Internet is utilized, the extent of the Internet's impact on business performance, and the extent the firms are prepared to take advantage of the Internet varies from country to country and from industry to industry. Based on data collected from 54 firms in the U.S. and 135 in South Korea, we compared the two countries (U.S. and South Korea) and two major industry groups (manufacturing and service) regarding the pattern of Internet utilization on the Internet from a value chain perspective. The findings show that U.S. companies utilize the Internet more extensively in such areas as human resources management, automation, sales, and advertising than the South Korean counterparts. However, we did not find a statistically significant difference in the way the two countries use the Internet within a value chain model. We also compared Internet practices by industry sector (i.e., service vs. manufacturing) within each country. The results show that firms in the service sector tend to use the Internet more extensively than the manufacturing counterparts in both countries. Particularly in Korea the difference between the sectors was significant in the extent to which they utilized the Internet to support such business activities as inter-organizational alliance, communication, and marketing.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.1
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• pp.35-42
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• 2015

Injection molding is a high efficient manufacturing technology for producing plastic parts. On the other hand, the warpage of molded plastic parts is an ubiquitous problem in the injection molding process. The main objective of this study was to minimize the amount of warpage occurring in the injection molding process of a hopper of ATDPS made of crystalline polymer (PP) instead of amorphous polymer (ABS). The moldflow CAE simulation was conducted for the molding process of the hopper to clarify the injection moldability, shear rate, shear stress, warpage by changing the gate shape and the number of ribs installed on the top of the hopper flange. The wide gate shape of runner system and multiple rib installation were found to be useful for minimizing the warpage of the hopper. The validity of the CAE simulations was supported by the injection molding experiment for the optimized design case.

• Journal of Intelligence and Information Systems
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• v.12 no.3
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• pp.83-93
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• 2006

This paper is wireless location awareness technology using RFID. We investigates the Location of the received Signal strength reported by RF Analyses of the data are performed to understand the underlying features of location fingerprints. The system is performed factors the extreme environmental Emit signal, which consists of a unique 5000 Terminals. The Location Service have become very popular in many service industries, purchasing and distribution logistics, industry, manufacturing companies and a parking place. The Technically optimal Solution would be the storage of Intelligence information in the most common form of electronic data-carrying device in use in everyday life is the smart card based upon a contact field (telephone smart card, bank cards). The method of an indoor positioning experiment system is compared using measured Location data and a charge of service. The result of research showed the following: first, to check out the mechanism between benefit of system installation and operation of Active RFID. Second, it contributed on indoor wireless location intelligence system efficiency.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.11
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• pp.2145-2152
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• 2017

As the ubiquitous paradigm that allows users to access the Internet anytime and anywhere is expanding, the expectation and interest of the Internet is increasing. As interest in the Internet has increased, interest in open source hardware has also increased. As a result, the maker, who is a creator who actually uses the digital production tools to create a product that he thought, is emerging as a new trend. As these makers shared how to make products, the 'maker movement', an open source manufacturing movement, spread. In the case of the domestic market, the government's policy support is also stimulating the maker movement. However, compared to developed countries, there is not enough awareness and environment of maker culture, and only open platform hardware and software are used without special education / development equipment or kit for maker.

• The Journal of the Korea Contents Association
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• v.7 no.12
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• pp.245-253
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• 2007

In this paper, we propose an effective web service software platform for remote monitoring and control. We removed the servlet container for better web service performance so as to improve the gSOAP processing which is an essential element of web service implementation. Furthermore, we designed the web service server/client software platform which can be applied to robot or ubiquitous sensor applications. For validation of this study we tested it by manufacturing robot hardware for monitoring control which combined tanks and sensors on a LDS4000 engine board mounted with a PXA270 processor. The practical excellence and the efficiency of the result of this study was validated by the comparison of gSOAP message exchange load between the web service client application and the conventional remote monitoring control technique through a web server.

• Tissue Engineering and Regenerative Medicine
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• v.15 no.6
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• pp.673-697
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• 2018

BACKGROUND: Cartilage tissue engineering (CTE) aims to obtain a structure mimicking native cartilage tissue through the combination of relevant cells, three-dimensional scaffolds, and extraneous signals. Implantation of 'matured' constructs is thus expected to provide solution for treating large injury of articular cartilage. Type I collagen is widely used as scaffolds for CTE products undergoing clinical trial, owing to its ubiquitous biocompatibility and vast clinical approval. However, the long-term performance of pure type I collagen scaffolds would suffer from its limited chondrogenic capacity and inferior mechanical properties. This paper aims to provide insights necessary for advancing type I collagen scaffolds in the CTE applications. METHODS: Initially, the interactions of type I/II collagen with CTE-relevant cells [i.e., articular chondrocytes (ACs) and mesenchymal stem cells (MSCs)] are discussed. Next, the physical features and chemical composition of the scaffolds crucial to support chondrogenic activities of AC and MSC are highlighted. Attempts to optimize the collagen scaffolds by blending with natural/synthetic polymers are described. Hybrid strategy in which collagen and structural polymers are combined in non-blending manner is detailed. RESULTS: Type I collagen is sufficient to support cellular activities of ACs and MSCs; however it shows limited chondrogenic performance than type II collagen. Nonetheless, type I collagen is the clinically feasible option since type II collagen shows arthritogenic potency. Physical features of scaffolds such as internal structure, pore size, stiffness, etc. are shown to be crucial in influencing the differentiation fate and secreting extracellular matrixes from ACs and MSCs. Collagen can be blended with native or synthetic polymer to improve the mechanical and bioactivities of final composites. However, the versatility of blending strategy is limited due to denaturation of type I collagen at harsh processing condition. Hybrid strategy is successful in maximizing bioactivity of collagen scaffolds and mechanical robustness of structural polymer. CONCLUSION: Considering the previous improvements of physical and compositional properties of collagen scaffolds and recent manufacturing developments of structural polymer, it is concluded that hybrid strategy is a promising approach to advance further collagen-based scaffolds in CTE.

• Korean Journal of Food Science and Technology
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• v.3 no.1
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• pp.6-14
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• 1971

Crystalline Mucor rennin and Mucor rennet from Mucor pusillus var. Lindt was compared with Hansen's calf rennet in its properties as a milk clotting enzyme. The method of Gouda type cheese from domestic milk was established by using of Crystalline Mucor rennin and Mucor rennet. The cheese produced by using of Mucor rennet as a milk clotting enzyme sometimes had bitter taste, it can be reduced with using Crystalline Mucor rennin, instead of Mucor rennet. It was also found out that these cheeses could be colored by the pigment from Cape Jasmine which is wildly ubiquitous in Korea.