• Journal of Surface Science and Engineering
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• v.36 no.3
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• pp.284-289
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• 2003

In this study, the prediction on the quality of tools after coating process has been investigated. Under different coating conditions, cutting resistances have been obtained and analyzed with a tool dynamometer to provide optimized coating conditions. The optimized coating conditions Lhave been computed with the most effective factors found by S/N ratio of Taguchi method. To evaluate the influence of the factors on cutting efficiency through the minimum of number of experiment times, the way of neural network design using Taguchi method has been employed.

• International Journal of High-Rise Buildings
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• v.6 no.2
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• pp.177-185
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• 2017

This research suggests the most effective way for improving energy efficiency in tall buildings is a "fabric-first" approach. This involves optimizing the performance of the building form and envelope as a first priority, with additional technologies a secondary consideration. The paper explores a specific fabric-first energy standard known as "Passivhaus". Buildings that meet this standard typically use 75% less heating and cooling. The results show tall buildings have an intrinsic advantage in achieving Passivhaus performance, as compared to low-rise buildings, due to their compact form, minimizing heat loss. This means high-rises can meet Passivhaus energy standards with double-glazing and moderate levels of insulation, as compared to other typologies where triple-glazing and super-insulation are commonplace. However, the author also suggests that designers need to develop strategies to minimize overheating in Passivhaus high-rises, and reduce the quantity of glazing typical in high-rise residential buildings, to improve their energy efficiency.

• Bulletin of the Korean Chemical Society
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• v.30 no.2
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• pp.297-301
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• 2009

We have developed the yttrium oxide (YNP) or ytterbium oxide (YbNP) nanoparticle/polymer matrices for the size-dependent separation of DNA ranging from 100 bp to 9,000 bp. High separation efficiency (> $10^6$ plates/m) and the baseline resolution for various DNA standards (100 bp, 500 bp, and 1 kbp DNA ladder) were obtained in 10 min with these matrices. The effects of concentrations of both polyethylene oxide (PEO) and nanoparticles were investigated and the highest performance was obtained at 0.02% PEO with 0.02% YNP or YbNP. Similar sieving power for both YNP and YbNP matrices was observed probably due to the similar sizes of nanoparticles, resulting in the formation of comparable sieving networks for DNA separation. For the reduction of electrosmotic flow, either dynamic or permanent coating of the capillary inner wall was compared and it turned out that PEO was superior to polyvinylpyrrolidone (PVP) or polyacrylamide (PAA) for better separation efficiency.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.11a
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• pp.222-223
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• 2014

According to the improvement of IT technology, an enhanced efficiency of management system in the construction industry is expected since a quotation system with BIM (Building Information Modeling) technique effectively estimates construction materials. For an enhanced efficiency of management system, related guidelines, standards, and manuals based on BIM are required, but the lack of this information causes difficulty to utilize in practice. In the paper, the satisfaction analysis was performed in order to promote the completeness of construction estimating manager that can be presented criteria and details of BIM-based quantity-takeoff, classification criteria.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.10 no.16
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• pp.19-26
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• 1987

Since many small and medium sized enterprises have lack of funds to install the full scale Computer Aided Process Planning this study has been attempted to develop a part of computer generated production information system for a start. The system is programmed by DBASE III and BASIC languages for the IBM-PC competables for the sake of user's convenience. The system consisted of four major parts. The first part is a computerized work measurement system for applying WF predetermined time standards. The second part is a computerized forecasting and loading system for applying various statistical techniques. The third part is a GT scheduling system programmed by BASIC for applying heuristic scheduling method. Finally, the last part is a simulation system for GT scheduling efficiency test which is programmed by SIMAN simulation language.

• Journal of Electrical Engineering and Technology
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• v.13 no.5
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• pp.1901-1907
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• 2018

This paper is a study for accurate iron loss calculation of a cylindrical linear machine for free piston engine. This study presents that it is possible to accurately predict power loss in ferromagnetic laminations under magnetic flux by specially considering the dependence of hysteresis, classical, and excess loss components on the magnetic induction derivative. Significant iron loss in the armature core will not only compromise the machine efficiency, but may also result in excessive heating, which could lead to irreversible deterioration in the machine performance. Thus, correct prediction of power losses under a distorted flux waveform is therefore an important prerequisite to machine design, particularly when dealing with large apparatus where stringent efficiency standards are required. Finally, it will be discussed about the iron loss in various materials of cylindrical linear electric machine by geometric and electrical parameters. It will give elaborate information about the perfect design and design rules of cylindrical linear machine and in parallel tools for the calculation, simulation and design will be available.

• Proceedings of the KIPE Conference
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• 2007.07a
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• pp.226-228
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• 2007

SRM drive systems are designed to meet operating standards such as low cost, constant torque independent of rotor position, a desired operating speed range, high efficiency, and high performance. In applications using small motors, low cost and high performance with self-starting capabilities are highly desired. This paper discusses a novel two phase SRM (TPSRM) that has high performance characteristics with self-starting capability, low manufacturing cost with a two phase inverter and simple magnetic structure, and high efficiency. The principle of operation, analysis, and simulation for design are presented. The machine design is verified using finite element analysis (FEA) software. Analysis and simulation results are given to validate the TPSRM design.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.10
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• pp.1380-1391
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• 1997

A 150 m$^{3}$/hr, 30 kg/cm$^{2}$, air-cooled 3-stage reciprocating air compressor is designed to be used in starting large diesel engines. A basic design procedure is presented to meet the targeted pressure and flow rate, and especially the volumetric efficiency. Temperature and stress analyses of the cylinder are performed using FEM modelings. The dynamics of valve system is analyzed and stress at the valve seat due to valve impact is evaluated. To reduce friction loss and wear at the compressor engine system, tribological design practices are suggested. Fin-type coolers are designed to dissipate generated compression heat at each stage. Finally, a prototype is manufactured and performance test is carried out utilizing an air tank. Performance results are compared to the design targets, other foreign specifications, and some quality standards.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.417-422
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• 2006

On trends of 'well-being', heat recovery ventilators(HRV) are recently installed in high rise buildings. HRV is not energy saving instrument but ventilating one. But many people have not been aware of the accurate fact. In this study, performances of HRV are tested under foreign and domestic standards. Especially air-tightness is measured three times by using gas concentration method and pressing equipment. Wet effective ventilating air volume is acquired by solving gas concentration equations. After research air-tightness and effective ventilating air volume must be more focused on than heat transfer efficiency to select the optimal HRV. Heat transfer efficiency must be adjusted by air-tightness results.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.1
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• pp.385-405
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• 2019

High Efficiency Video Coding (HEVC) enables significantly improved compression performance relative to existing standards. However, the advance also requires high computational complexity. To accelerate the intra prediction mode decision, a minimum risk Bayesian classification framework is introduced. The classifier selects a small number of candidate modes to be evaluated by a rate-distortion optimization process using the sum of absolute Hadamard transformed difference (SATD). Moreover, the proposed method provides a loss factor that is a good trade-off model between computational complexity and coding efficiency. Experimental results show that the proposed method achieves a 31.54% average reduction in the encoding run time with a negligible coding loss of 0.93% BD-rate relative to HEVC test model 16.6 for the Intra_Main common test condition.