• Journal of Korean Institute of Industrial Engineers
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• v.41 no.1
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• pp.97-104
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• 2015

An electric-motor which uses electric energy to dry laundry in a dryer generates wind by rotating a fan. The roles of electric motor and fan are crucial for drying. To reduce the noises or vibration, their performances should be improved. However, it requires a relatively high cost to redesign them. In this case, redesigning the fan case rather than the motor or the fan would be easier and cheaper. This paper is to apply Taguchi dynamic characteristic concept with the ideal function of energy conversion to redesign the fan case. Not only the increase of the wind power but also the decrease of noise, vibration and the other side effects are resulted.

• Journal of Advanced Marine Engineering and Technology
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• v.28 no.5
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• pp.837-846
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• 2004

This paper presents a screening technique for greatly reducing the computation involved in determining the optimal location and types of Flexible AC Transmission System (FACTS) devices in a large power system. The first-order sensitivities of the generation cost for various FACTS devices are derived. This technique requires solving only one optimal power flow (OPF) to obtain sensitivities with respect to FACTS device control variables for every transmission line To implement a sensitivity-based screening technique, we used a new UPFC model, which consists of an ideal transformer with a complex turns ratio and a variable shunt admittance. A S-bus system based on the IEEE 14-bus system was used to illustrate the technique.

• Journal of the Korean Society of Industry Convergence
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• v.19 no.3
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• pp.133-143
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• 2016

The objective in here is to find the density, stiffness, and strength of truss-wall rectangular (TWR) model which is combined with lattice truss (MLT) inside space. The TWR unit-cell model is defined as a unit cell originated from a solid-wall rectangular (SWR) model and it has an empty space inside. Thus, the empty space inside of the TWR is filled with lattice truss model defined as TWR-MLT. The ideal solutions derived of TWR-MLT are based on TWR with MLT model and it has developed by Gibson-Ashby's theory. To validate the ideal solutions of the TWR-MLT, ABAQUS software is applied to predict the density, strength, and stiffness, and then each of them are compared with the Gibson-Ashby's ideal solution as a log-log scale. Applied material property is stainless steel 304 because of cost effectiveness and easy to get around. For the analysis, SWR and TWR-MLT models are 1mm, 2mm, and 3mm truss diameter separately within a fixed 20mm opening width. In conclusion, the relative Young's modulus and relative yield strength of the TWR-MLT unit model is reasonably matched to the ideal expectations of the Gibson-Ashby's theory. In nearby future, TWR-MLT model can be verified by advanced technologies such as 3D printing skills.t.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2006.05a
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• pp.21-40
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• 2006

[ ${\Box}$ ] Opportunities for PRAM Nearly ideal memory characteristics Potential for high density & low cost memory ${\Box}$ Technical Challenges Writing current reduction is the most urgent issue. ${\to}$ chalcogenide, programming volume, current density, heat loss control Improvement of writing speed, reliability ${\Box}$ Prospects (PRAM as a Mainstream Memory) Evenn, We have demonstrated 256Mb PRAM Realization of high density and low cost PRAM with good reliability will be key succss factor. We need to develop PRAM specific applications.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.6
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• pp.506-513
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• 2004

The objective of this paper is to evaluate the economic performance of latent and sensible energy transportation systems. LCC (Life-Cycle Cost) analysis is a practical method and a guideline for evaluating the economic performance of considered systems during the Life-Cycle Period. By comparing the LCC of alternatives, The most ideal alternative is determined which has the lowest LCC. It is concluded that the cost of STA (Solution Transportation Absorption system) can be reduced by 67% to that of sensible energy transportation for study period with 10 km transportation distance.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.6
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• pp.582-589
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• 2002

This paper presents 12.2 GHz ~ 12.7 GHz frequency band reflection type 5-bit digital phase shifter with constant insertion loss property that was fabricated with relatively low cost's InGaAs HEMT for amplifier. The unavoidable large insertion loss difference between on and off states of HEMT, when it is designed by conventional design theory based on ideal switching device, is removed by transforming the HEMT impedances at on and off states to other proper values connecting a certain length transmission line to HEMT and then applying the conventional design theory. The fabricated 5-bit digital phase shifter shows very good insertion loss properties of less than 1.5 dB insertion loss difference and -4.5 dB ~ -6 dB insertion loss in 35 phase steps at 12.2 GHz ~ 12.7 GHz. These results verify the design method presented in this paper, which is useful to design phase shifter of constant insertion loss with non-ideal switching device.

• Journal of Information Technology Services
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• v.10 no.4
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• pp.229-242
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• 2011

It is necessary to have measurement and analysis activity for managing software project. At least, every project measures time and cost in order to figure it out whether it will finish within its deadline. CMMI has Measurement and Analysis process in Maturity Level 2. In Measurement and Analysis process, Indicators for decision making in project management are defined and analysis procedure of the measurements to get the indicators are specified. Also, the way of collecting the data and storing them is also planned. Establishing efficient and effective measurement and analysis process in the organization by improving existing process is very important for project success. In this paper, we provide a method for analyzing the measurement and analysis process and improving it based on IDEAL model. It will support the organizations which are trying to adopt CMMI to establish measurement and analysis process.

• Industrial Engineering and Management Systems
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• v.10 no.2
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• pp.123-127
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• 2011

Nowadays, green purchasing, stop global warming, love the mother earth, and others that related to environment become hot issues. Manufactures industries tend to more active and responsive to those issues by adopting green strategies or program like Environmentally Conscious Manufacturing (ECM). In this article, an electronic company had applied 12 ECM Program and tries to choose one of those programs using 6 criteria, such as total cost involved, quality, recyclable material, process waste reduction, packaging waste reduction, and regulation compliance. By using multi-criteria decision making model, i.e. Analytical Hierarchy Process (AHP), Technique for Order Preference by Similarity to Ideal Solution (TOPSIS), and Modified TOPSIS methods, the ECM Program 9 (Open pit) is the best option.

• The Journal of Fisheries Business Administration
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• v.40 no.3
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• pp.29-49
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• 2009

There are various types of predictable economic benefits to restoring beneficial uses from contaminated marine sediment cleanup. These benefits can be derived from reduction in aquatic animals died or infected, increase in their consumption recovery, increase in tourism including recreational fishing, reduction in human health risk, increase in amenity and aesthetics, increase in ecosystem integrity, and so on. The paper focuses on estimating the net increase in value for producers and consumers from producing and consuming those fish due to the pollution reduction of marine contaminated cleanup project. Almost Ideal Demand System(AIDS) is employed for estimate of the demand for fish, and the production cost function for fish are determined using market data. The result shows 10.8 billion won per year for economic surplus to the net increase for producers and consumers.

• Journal of applied mathematics & informatics
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• v.13 no.1_2
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• pp.323-334
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• 2003

This paper presents a goal-programming (GP) model for management decision-making for sugarcane fertilizer mix problems. Sensitivity analysis on the priority structure of the goals has been performed to obtain all possible solutions. The study uses Euclidean distance function to measure distances of all possible solutions from the ideal solution. The optimum solution is determined from the minimum distance between the ideal solution and other possible solutions of the problem. The optimum solution corresponds to the appropriate priority structure of the problem in the decision-making context. furthermore, the results obtained from sensitivity analysis on the cost of combination of fertilizers confirm the priority structure.