• 한국자기학회:학술대회 개요집
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• 한국자기학회 2013년도 자성 및 자성재료 국제학술대회
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• pp.89-89
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• 2013

Rare earth (RE) - transition metal based high energy density magnets are of immense significance in various engineering applications. $Nd_2Fe_{14}B$ magnets possess the highest energy product and are widely used in whole industries. Simultaneously, composite alloys that are cheap, cost effective and strong commercially available have drawn great attention, because rare-earth metals are costly, less abundant and strategic shortage. We designed rare-earth free alloys and fabrication process and developed novel route to prepare $Nd_2Fe_{14}B$ powders by wet process employing spray drying and reduction-diffusion (R-D) without the use of high purity metals as raw material. MnAl-base permanent magnetic powders are potentially important material for rare-earth free magnets. We have prepared the nano-sized MnAl powders by plasma arc discharge and micron-sized MnAl powders by gas atomization. They showed good magnetic property, compared with that from conventional processes. $Nd_2Fe_{14}B$ powders with high coercivity of more than 10 kOe were successfully synthesized by adjusting R-D step, followed by precise washing system. It is considered that this process can be applied for the recycling of RE-elements extracted from ewaste including motors.

• 한국CDE학회논문집
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• 제14권3호
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• pp.186-196
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• 2009

Mass customization (MC) is a business practice that aims to provide customers with customized products and services at near mass production efficiency. To achieve the aim, a number of methods to implementing MC are proposed. However, most of them require changes in entire process of the company, which make companies hesitate to implement MC even if it is essential to survive. In this paper, we proposed alternatives to partially implement MC for quick adaptation of MC. The base line assumption is not to change the production lines. The pros and cons of alternatives are given by qualitative and quantitative evaluation. Especially, by giving radar chart analysis of the quantitative measures, we give insight on the changes in the business performance measures, such as time to market and cost. Proposed alternatives are based on sub-processes such as purchasing raw materials, production process changes and packaging for efficient logistics. In this way, companies are able to provide customized products with small changing of the current manufacturing system. The process and benefit of the proposed strategy is verified by real world cases of a Korean health food company.

• 미생물과산업
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• 제15권1호
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• pp.38-42
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• 1989

Industrial strain Improvement is concerned with developing or modifying microorga-nisms used In production of commercially important fermentation products. The aim is to reduce the production cost by improving productivity of a strain and manipulating specific cilarafteristic such as the ability to utilize cheaper raw materials or resist bacteriophages. The traditional empiri-cal approach to strain improvement is mutation combined with selection and breeding techniques. It is still used by us to improve the productivity of organisms in amino acids. organic acids andenzymes production. The breeding of high L-lysine-producing strain Au112 is one of the outstanding examples of this approach. It is it homoserine auxotroph with AEC, TA double metabolicanalogue resistant markers. The yield reaches 100g/1. Resides, the citric acid-producing organism Aspergillus nuger, Co827, its productivity reches the advanced level in the world, is also the result of a series mutations expecially with Co Y-radiation. The thermostable a-amylaseroducing strain A 4041 is the third example. By combining physical and chemical multations. the strain ,A 4041becomes an asporogenous, catabolite derepressed mutant with rifamycin resistant and methionine, arginine auxotroph markers. The a-amylase activity reaches 200 units/ml. The fourth successful example of mutation in strain improvement is the glucoamylase-producing strain Aspergillus nigerSP56 its enzyme activity is 20,000 units/ml, 4 times of that of the parental strain UV_11. Recently recombinant DNA approach Provides a worth while alternative strategy to Industrial strain improve-ment. This technique had been used by us to increase the thermostable a-amylase production and on some genetic researches.

• 대한안전경영과학회지
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• 제13권2호
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• pp.203-210
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• 2011

Incheon Port has been served as not only the center of the Yellow Sea and port for trade with China but also domestic gateway port for the metropolitan area, playing a professional role as the greatest domestic Port which processes a variety of items such as imported raw materials, bulk cargo, oil and gas and so on. This study was conducted based on step by step business process between port entry and departure of ship, and incurred cost according to port industry classification and performance on the port facility. Bulk cargo and general cargo such as grain, food, steel, scrap metal, wood, coal, LNG, LPG and oil etc., which have a vast majority of import goods, have been treated by 57,062 thousand tons and 7,409 thousand tons of container cargo were processed at Incheon Port in 2009. Bulk vessels and carriers moving items such as LPG, LNG and oil recorded 38,836 thousand won and full-container vessels recorded 11,001 thousand won as the amount of notified port facility usage fees in 2008.

• International Journal of Reliability and Applications
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• 제13권1호
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• pp.1-17
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• 2012

This Paper deals with the stochastic behavior and failure analysis of a Viscose Staple Fibre Plant which produces fibre for making clothes. The fibre making plant is a complex system with various subsystems as: Vendor (supplies Charcoal and Sulphur, raw materials for the process), Carbon di sulphide Plant, Acid Plant, Pulp Plant and Processing Plant. The considered system can completely fail due to failure of any of the subsystems. The Carbon di Sulphide Plant can fail in two different ways, due to lack of Sulphur or Charcoal. Processing Plant has the configuration 5-out-of-10: d and 6-out-of-10: f. It is also assumed that the system can fail due to workers strike and catastrophic failure. All failures follow exponential time distribution whereas all repairs follow general time distribution. Preventive Maintenance policy has been applied to reduce the failure in the system. Various reliability characteristics such as transition state probabilities, steady state behavior, reliability, availability, M.T.T.F and the cost analysis have been obtained using supplementary variable technique and Gumbel-Hougaard copula methodology.

• Computers and Concrete
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• 제24권4호
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• pp.283-293
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• 2019

The limited availability of raw materials and increasing service demands for pavements pose a unique challenge in terms of pavement design and concrete material selection. The self-compacting rubberized concrete (SCRC) can be used in pavement design. The SCRC pavement slab has advantages of excellent toughness, anti-fatigue and convenient construction. On the premise of satisfying the strength, the SCRC can increase the ductility of pavement slab. The aim of this investigation is proposing a new method to predict the crack growth and flexural capacity of large-scale SCRC slabs. The mechanical properties of SCRC are obtained from experiments on small-scale SCRC specimens. With the increasing of the specimen depth, the bearing capacity of SCRC beams decreases at the same initial crack-depth ratio. By constructing extended finite element method (XFEM) models, crack growth and flexural capacity of large-scale SCRC slabs with different fracture types and force conditions can be predicted. Considering the diversity of fracture types and force conditions of the concrete pavement slab, the corresponding test was used to verify the reliability of the prediction model. The crack growth and flexural capacity of SCRC slabs can be obtained from XFEM models. It is convenient to conduct the experiment and can save cost.

• 복식문화연구
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• 제27권1호
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• pp.57-63
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• 2019

Due principally to the desire to seek lower production costs, the bulk of the world's textile and clothing manufacture migrated to low-cost zones, mainly outside Europe, over the course of the late-twentieth century. In the early-twenty-first century, fast fashion became a dominant force worldwide, with 'Western' retail buyers hunting cheaper deals from clothing manufacturers (mainly in Asia), and with occasional disasters not changing matters beyond the duration of a fashion season. Progressively, seams became narrower, cheaper raw materials were used and durability was no longer an aim. Why bother to do otherwise? This was what the 'Western' consumer wanted: fashion to be worn only a few times and then discarded, despite the fact that vast amounts of human, technological and financial resources were wasted in such a quest. By the end of the second decade of the twenty-first century, the production of textile and clothing products continued to contribute substantially to global warming. This paper reviews briefly the current conditions of manufacture, and argues that the research agenda should be focused on addressing the implications of a progressively changed focus, not on fast-fashion products, but instead on the production of products with greater durability. Meanwhile 'Western' consumers need to turn away from fast fashion and realise that waste is bad for their economy and their society. It is argued further, that after a period of re-adjustment, substantial financial rewards await the national textile and clothing industries that undergo such a turn around.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 봄 학술논문 발표대회
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• pp.144-145
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• 2020

Recently, the cement industry has been using various wastes as raw materials and fuel for cement as an eco-friendly business. However, most of these waste resources contain large amounts of chloride and alkali, which are concentrated in manufacturing facilities and adversely affect cement production products. Accordingly, in the cement production process, the chlorine ion contained in cement is managed by introducing the Chlorine Bypass System (CBS) into the manufacturing facility and releasing the dust. However, the processing volume of CBS-Dust has been limited due to the shortage of domestic processing companies, and the cost has also been raised, requiring measures to be taken in dealing with CBS-Dust. In this study, rheological properties of CBS-Dust incorporated paste are tested. With the increase of CBS-Dust, flow was decreased due to enhanced viscosity.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 봄 학술논문 발표대회
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• pp.75-76
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• 2020

Use fire resistant construction methods, of which fire resistant boards are used to protect buildings and structures from fire. However, in the case of fire resistant boards, the unit price of the main raw material is high and the cost efficiency is low. There have been studies to apply oyster shells to fire resistant boards to solve these problems. On the other hand, egg shells are also considered to be applicable to fire-resistant boards with components like oyster shells, but there is no case of using egg shells as building materials. Therefore, in this study, we confirmed the physical properties of egg shell powers used as mortar filler and compared them with the fire resistant board flexural strength standard. As a result, it was judged that the powder of egg shells could be used as a building material, because the standards for the flexural strength of fire resistant boards were satisfied except for a part.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.477-480
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• 2015

Construction projects are high-risk activities. When undertaking such projects in an international setting, it can be complicated by foreign exchange (FOREX) fluctuation risk. This affects the construction business performance in various ways, namely its progress due to delays, which in turn create further problems, specifically cost overruns as a result of price increase in raw materials, disputes, arbitration, litigation and even, total abandonment. Thus, the effective management of FOREX fluctuations is crucial. Previous studies have focused on the need for contract safeguards, adequate insurance, careful planning and management, as well as foreign exchange futures hedging to address some of the risks triggered by FOREX fluctuations. An analysis of FOREX fluctuations in the international construction industry revealed that more often it was focused on project-specific issues. Currently, there is a relative lack of awareness on Organizational Capabilities (OC), the abilities that owned by the organization, which is essential in managing the impact of FOREX fluctuations. Where research has focused on OC, these are viewed in isolation. Therefore, this study attempts to close the gap by proposing a framework on managing the impact of FOREX fluctuations in the international construction industry, employing the OC perspective.