• Journal of Korean Society of Industrial and Systems Engineering
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• v.28 no.2
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• pp.8-17
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• 2005

This paper dealt with a kind of heterogeneous vehicle routing problem with known demand and time deadline of customers. The customers are supposed to have one of tight deadline and loose deadline. The demand of customers with tight deadline must be fulfilled in the deadline. However, the late delivery is allowed to customers with loose deadline. That is, the paper suggests a model to minimize total acquisition cost, total travel distance and total violation time for a fleet size and mix vehicle routing problem with time deadline, and proposes a heuristic algorithm for the model. The proposed algorithm consists of two phases, i.e. generation of an initial solution and improvement of the current solution. An initial solution is generated based on a modified insertion heuristic and iterative Improvement procedure is accomplished using neighborhood generation methods such as swap and reallocation. The proposed algorithm is evaluated using a well known numerical example.

• Biomolecules & Therapeutics
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• v.6 no.1
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• pp.56-62
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• 1998

Mutagenicity of recombinant human erythropoietin (rhEPO) was examined in the reverse mutation test on bacteria, in the chromosomal aberration test on cultured mammalian cells and in the micronucleus test on mice. The reverse mutation test was performed by a plate incorporation method with or wothout a metabolic activation system (59 Mix) using Salmonella typhimurium strain TA100, TA1535, TA98 and TA 1537. The rhEPO did not significantly increase revertant colonies in any of the test strains under any conditions at dose levels ranging from 1000 H/ml to 62.5 lu/plate, compared with the vehicle control. In the chromosomal aberration test using cultured Chinese Hamster Lung (CHL) cells, the number of aberrant cells was not increased in the presence or absence of 59 Mix at concentrations of 1000 lU/ml to 250 lU/ml, compared with the vehicle control. In the micronucleus test, male ICR mice were given rhEPO intraperitoneally at a dose level of 25000, 12500 and 6250 lU/kg. The incidence of bone marrow micronucleated polychromatic erythrocytes was not different from that of the vehicle control. From these results, rhEPO is considered to be non-mutagenic under the present test conditions.

• Journal of Korean Institute of Industrial Engineers
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• v.1 no.1
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• pp.41-56
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• 1975

In the past the pattern of business down-trend usually appeared in the form of, first, decrease in facility investment, then decrease in inventory level, followed by reduced level of consumption. But the pattern nowadays is becoming just the opposite, that is, first, consumption decrease, then inventory level increase, followed by restriction of facility investment. Also in the past, the greater effort was placed in strengthening of hardware areas through optimization and modernization of production means on the premise of sales. But lately software areas take most of the main effort to establish production mean with sales as its objective. Under these circumstances one of the real problems facing production activities today is the conflicting relationship between sales and production functions. This occurs due to differences of their view points. Then, in order to achieve maximum profit at the least cost, which is the ultimate objective of a production activity, the need arises to effectively coordinate sales demand and plant production capacity. For this purpose strong control means and function must be devised. In our case study example we illustrate a management technique for a combined planning function, of optimal coordination of product mixes utilizing a computerized linear programming model as control means of attaining maximum profit. It is hoped that this example help achieve some of corporate objectives.

• Journal of the Korean Society of Industry Convergence
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• v.10 no.4
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• pp.207-211
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• 2007

The durable lifetime of RC structures is shortened by various reasons, which are the generation of cracks in construction and service term, the exterior deterioration according to climatic condition, the surface damage due to chloride attack and the corrosion of reinforced bars. The durability of concrete structures is nevertheless able to be increased by the method and the material of reinforcement and repair. The epoxy resin is widely used for reinforment and repair of concrete because of the superiority in mechanical property, adhesive property, abrasion resistance, impact resistance and chemical resistance. The epoxy cement mortar with hardening agent has a lot of disadvantages that are troublesome mixing work, weakened weatherability and high cost for hardening agent. In this study, the mix proportion of mortar is presented just only with epoxy resin and some admixtures, and the test result of mortar without hardening agent shows the higher strength than the mortar with hardening agent. In the mix proportion, the weight of epoxy resin must be less than 15% of the unit weight of cement, and 10% of unit weight of cement is adequate for the weight of admixtures.

• Journal of Communications and Networks
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• v.7 no.3
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• pp.377-384
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• 2005

The purpose of this research is to develop and evaluate a traffic engineering architecture that uses local state information. This architecture is applied to an Internet protocol radio access network (RAN) that uses multi-protocol label switching (MPLS) and differentiated services to support mobile hosts. We assume mobility support is provided by a protocol such as the hierarchical mobile Internet protocol. The traffic engineering architecture is router based-meaning that routers on the edges of the network make the decisions onto which paths to place admitted traffic. We propose an algorithm that supports the architecture and uses local network state in order to function. The goal of the architecture is to provide an inexpensive and fast method to reduce network congestion while increasing the quality of service (QoS) level when compared to traditional routing and traffic engineering techniques. We use a number of different mobility scenarios and a mix of different types of traffic to evaluate our architecture and algorithm. We use the network simulator ns-2 as the core of our simulation environment. Around this core we built a system of pre-simulation, during simulation, and post-processing software that enabled us to simulate our traffic engineering architecture with only very minimal changes to the core ns-2 software. Our simulation environment supports a number of different mobility scenarios and a mix of different types of traffic to evaluate our architecture and algorithm.

• Journal of the Korea Fashion and Costume Design Association
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• v.6 no.3
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• pp.19-29
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• 2004

The current fashion market is experiencing a lot of difficulties in fashion forecasting due to consumers' fast-changing lifestyle on fashion, changes in consumer behavior, and the segmentation of the fashion market. To cope with this harsh reality, many fashion enterprises have paid much attention to the SPA (Specialty Retailer's Store of Private Label Apparel) brand as a promising fashion marketing strategy in terms of which they can survive in the extremely competing fashion market. The SPA brand is in the stage of inception in Korea, but the SPA brands such as MUJI and UNIQLO are already dominating the fashion business in Japan. Korea has just started developing the SPA brand, but its technological development, which was triggered by the success of 'BASIC HOUSE', is rapidly evolving. Under these circumstances, the SPA brand is getting vital for the fashion market in efficiently realizing consumers' requirements, revolutionizing the method for providing product information and the process of Marketing Mix Program, and expressing the value of shop. This paper studies the nature of the SPA brand and fashion merchandising system, and in turn examine the differences between the visual merchandising of the existing fashion brands and the Japanese SPA brands that are used as the fashion marketing strategy which is driven by the up-to-date technological system. Centering around these issues, we propose a visual merchandising system for fashion enterprises which serves to develop Korean-style SPA brands.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.14 no.1
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• pp.245-251
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• 2014

Mix network plays a key role in electronic voting to preserve anonymity and lots of mixnet schemes have been proposed so far. However, they requires complex and costly zero-knowledge proofs to provide their correct mixing operations. In 2010, Seb$\acute{e}$ et al. proposed an efficient and lightweight mixnet scheme based on a cryptographic secure hash function instead of zero-knowledge proofs. In this paper, we present a more efficient and faster mixnet scheme than Seb$\acute{e}$ et al.'s scheme under the same assumption. Also, our scheme is secure.

• Advances in concrete construction
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• v.9 no.4
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• pp.367-374
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• 2020

Concrete surfaces, industrial floors, sidewalks, roads and parking lots are typically subjected to abrasions. Many studies indicated that the abrasion resistance is directly related to the ultimate strength of the cured concrete. Chemical reactions, freeze-thaw cycles, and damages under abrasion are among many factors negatively affecting the concrete strength and durability. One of the major solutions to address the abrasive resistance of the concrete is to use fibers. Fibers are used in the concrete mix to improve the mechanical properties, strength and limit the crack propagations. In this study, implementation of the steel fibers in concrete to enhance the abrasive resistance of the concrete is investigated in details. The abrasive resistance of the concrete with and without steel fibers is studied with the sandblasting technique. For this purpose, different concrete samples are made with various hooked steel fiber ratios and investigated with the sandblasting method for two different strike angles. In total, 144 ASTM verified cube samples are investigated and it is shown that those samples with the highest steel fiber ratios have the highest abrasive resistance. In addition, the experiments determine that there is a meaningful correlation between the steel fiber percentage in the mix, strike angle and curing time which could be considered for improving structural behavior of the fiber-reinforced concrete.

• Biomolecules & Therapeutics
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• v.4 no.3
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• pp.224-231
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• 1996

DA-5018, a non-narcotic analgesic agent, was examined for mutagenicity in the reverse mutation test on bacteria, chromosomal aberration test on cultured mammalian cells and micronucleus test on mice. The reverse mutation test was performed by a plate incorporation method with or without a metabolic activation system(S9 mix) using Salmonella typhimurium strain TA100, TA1535, TA98 and TA1537. DA-5018 did not significantly increase revertant colonies in any of the test strains under any conditions at concentrations ranging from 0.0049 to 1.25 mg/plate, compared with the vehicle control. In the chromosomal aberration test using cultured Chinese Hamster Lung(CHL) cells, DA-5018 did not increase the number of aberrant cells in the presence or absence of S9 mix at concentrations of 0.016 mM/plate to 0.25 mM/plate, compared with the vehicle control. In the micronucleus test, male ICR mice were given DA-5018 intraperitoneally at a dose level of 0.55, 1.10 and 2.20 mg/kg. The incidence of bone marrow micronucleated polychromatic erythrocytes in the DA-5018 treated mice was not significantly different from that of the vehicle control. These results indicate that DA-5018 does not have mutagenic potential under the present test conditions.

• Korean Journal of Computational Design and Engineering
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• v.22 no.1
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• pp.10-17
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• 2017

The recent 3D printing industry has been focusing on developing 3D printers to fulfill the user's need to bring more colorful and realistic outcomes. Several 3D printers have deployed multiple extruders to print different colors. However, this method has a limit on its availability of colors. To solve this, recent research is focused on using mixing chambers to mix the possible colors to provide more color availability. In this paper, we discuss the environment and algorithm behind the development of G-code which allows a gradation effect of the mix of two filaments. The generation algorithm to make gradient G-code has been implemented in Cura using C ++ and Python.