• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.1057-1060
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• 2003

This paper is about the optimized fabricated parameter in the EDMOSFET(Extended drain MOSFET) with a various temperature. As we know, the two important factors of EDMOSFET parameters are breakdown voltage and on Resistance. So, we have aims of the power EDMOSFET design to have high breakdown voltage and low on resistance. Thus in this paper, we will show the figure of merit in LDMOS (BV/Ron) in accordance with increase in temperature(300K-500K, step:50K), and measure electronic characteristics of power EDMOSFET. As a result, the important factors in design of EDMOS are temperature and Lg.

• Korean System Dynamics Review
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• v.3 no.2
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• pp.113-140
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• 2002

The cost-benefit analysis is a technique for assisting with decision about the use of society's scare resources. There exists no detailed assessment like cost-benefit analysis. But recently, many policy analysts criticized the merit of cost-benefit analysis. As it is, it can be said that partial or approximate estimates of benefit and cost may be more dangerous than helpful. The purpose of this study is to overcome the limit of traditional cost-benefit analysis. For this purpose, we use the system dynamics approach for setting up new cost-benefit analysis, which we named that ‘Dynamics Cost-Benefit Analysis'. The usefulness of ‘Dynamics Cost-Benefit Analysis' is as follows; finding structural causal relationship between cost factors and benefit factors, understanding the long-term behavior of systems economic feasibility. In this study, we apply 'Dynamic Cost-Benefit Analysis' to case that is construction investment of funeral house by local government sector.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.5C
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• pp.530-535
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• 2007

Disparity space image (DSI) technique is a method of establishing correspondence between a pair of images. It has a merit of generating a dense disparity map for each pixel. DSI has a cost function to be minimized, and it needs empirical weighting factors for occlusion penalty and match reward. This paper provides theoretical basis for the weighting factors, which depend on image noise and contrast between an object and background.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.87.1-87.1
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• 2011

For commercial applications, MEA development must be optimized in order to achieve high performance and low cost. There are many factors that affect the performance of MEA. Especially, the optimization of the method for preparing catalyst layer has great effect on the performance of MEA. Various methods have been used to prepare the catalyst layer of MEA. Among them, spraying method has a merit in that catalysis lay can be prepared with very flexible changes in catalyst layer as well as in the solvent composition of catalyst ink. In addition, in order to reduce the time required for manufacturing catalyst layer, an effort has been made to change the nozzle size and injection pressure of spray system. Further, the operation condition of spray system was changed in various ways in an effort to prepare optimum catalyst layer of MEA. Having optimized the operation condition of spraying system, comprehensive and diverse experiments were carried out concerning various factors that affect the performance of MEA. The present research report describes the results of more sub-categorized and more detailed experiments about the important factors (Nafion$^{(R)}$ ionomer, Relative humidity) which have been shown in previous experiments to exert greater effect on the performance of MEA.

• The Journal of the Acoustical Society of Korea
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• v.29 no.4
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• pp.278-285
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• 2010

The difference between training and test environments is one of the major performance degradation factors in noisy speech recognition and many silence feature normalization methods were proposed to solve this inconsistency. Conventional silence feature normalization method represents higher classification performance in higher SNR, but it has a problem of performance degradation in low SNR due to the low accuracy of speech/silence classification. On the other hand, cepstral distance represents well the characteristic distribution of speech/silence (or noise) in low SNR. In this paper, we propose a Cepstral distance and Log-energy based Silence Feature Normalization (CLSFN) method which uses both log-energy and cepstral euclidean distance to classify speech/silence for better performance. Because the proposed method reflects both the merit of log energy being less affected with noise in high SNR and the merit of cepstral distance having high discrimination accuracy for speech/silence classification in low SNR, the classification accuracy will be considered to be improved. The experimental results showed that our proposed CLSFN presented the improved recognition performances comparing with the conventional SFN-I/II and CSFN methods in all kinds of noisy environments.

• Journal of the Microelectronics and Packaging Society
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• v.17 no.2
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• pp.49-54
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• 2010

The n-type $Bi_2(Te,Se)_3$ powders were fabricated by melting/grinding method and were hot-pressed in order to compare thermoelectric properties of the hot-pressed specimens with those of the $Bi_2(Te,Se)_3$ ingot. Effects of mechanical milling treatment of the $Bi_2(Te,Se)_3$ powders on thermoelectric characteristics of a hot-pressed specimen were also examined. The hot-pressed $Bi_2(Te,Se)_3$ exhibited power factors of $27.3{\sim}32.3{\times}10^{-4}W/m-K^2$ which were superior to $24.2{\times}10^{-4}W/m-K^2$ of the ingot. The $Bi_2(Te,Se)_3$, hot-pressed after mechanical milling treatment of the powders, possessed a non-dimensional figure-of-merit of 1.02 at $100^{\circ}C$ and exhibited extrinsic-intrinsic transition at $130^{\circ}C$.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.3
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• pp.213-218
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• 2017

In this study, a reverse design of the F-theta lens was proposed for a 2D scanner in remote welding applications. The curvature and distance of the lens were set as variables, and the focal length of the lens was set as the marginal ray height. The ZEMAX commercial software was used to perform a simulation with unlimited iterations for the optimization process. The target value was optimized using the internal Merit function with the weight factors of focal length and spot diameter. The number of lenses was four, and the focal length obtained from the results was 135mm that is slightly less than that of the commercial lens, which is set with a focal length of 185 mm. The calculated spot diameters are $1.3{\mu}m$, $6.2{\mu}m$, and $16.1{\mu}m$ for $0^{\circ}$, $12.5^{\circ}$ and $23^{\circ}$ of incident laser beam, respectively. It is expected that an optimized lens design is possible by performing the reverse design of a lens by the ray tracing method.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.9
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• pp.4326-4334
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• 2013

This study is descriptive research, attempts to determine the status of elderly inpatients of veterans hospital' of drug awareness information, drug use status and drug Misusage. The subjects were 220 patients of aged 65 and over only five metropolitan areas nationwide in drug use in the Veterans Hospital, national merit, the study is from May to June. SPSS Win 18.0 program was used as the data analysis and a statistical statement by mean, standard deviation, t-test and ANOVA, and multiple regression analysis. As a results, there was showed a statistically significant level 'age', 'type of marriage', 'education', 'triage', 'health status' as the general characteristics of the subjects. It showed the 'age' of the variables that influence recognition in the area of drug awareness information, and drug Misusage and drug use status factors seemed to affect the 'health status'. Therefore, It need for a comparative study of elderly inpatients and inpatients of veterans hospital, the research should be qualitative research of veterans medical services to the on reasonable support measures in the Veterans Affairs health care system and national merit.

• Journal of Aerospace System Engineering
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• v.13 no.3
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• pp.56-63
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• 2019

Performance analyses were performed on a propeller developed for use in a PAV (Personal Air Vehicle) under 600 kg Maximum Take-Off Weight (MTOW). The actuator disc theory and CFD analyses were used to estimate the hovering time with regards to MTOW variation for a given battery weight. The interference induced power factor kint was introduced to account for the effect of flow interference between the propellers and to estimate the performance of counter-rotating propellers. The Maximum Figure of Merit (FM) value of the propeller pitch was determined and the design RPM range for the required power inversely obtained from the CFD results. Previous research indicate that the flight time of large multi-copter is limited by the available battery energy density. Similarly, the propeller pitch settings and spacing are important factors in reducing the kint value.

• International conference on construction engineering and project management
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• 2020.12a
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• pp.343-352
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• 2020

Modular integrated construction (MiC) is an innovative construction method where components of a building are manufactured in an offsite factory, trucked to the job site in sections, set in place with cranes, and assembled together to form a whole building. Where circumstances merit, favorable conditions exist and implemented effectively; MiC improves project performance. However, several key factors need to converge during implementation to realize the full benefits of MiC. Thus, a thorough understanding of the factors which are critical to the success of MiC projects is imperative. Drawing on a systematic review of 47 empirical studies, this research identified 25 key success factors (KSFs) for MiC projects. Of these, the five topmost cited KSFs for MiC projects include effective working collaboration and communication among project participants; standardization, optimization, automation and benchmarking of best practices; effective supply chain management; early design freeze and completion; and efficient procurement method and contracting. The study further proposed a conceptual model of the KSFs, highlighting the interdependences of people, processes, and technology-related KSFs for the effective accomplishment of MiC projects. The set of KSFs is practically relevant as they constitute a checklist of items for management to address and deal with during the planning and execution of MiC projects. They also provide a useful basis for future empirical studies tailored towards measuring the performance and success of MiC projects. MiC project participants and stakeholders will find this research useful in reducing failure risks and achieving more desired performance outcomes. One potential impact of the study is that it may inform, guide, and improve the successful implementation of MiC projects in the construction industry. However, the rigor of the analysis and relative importance ranking of the KSFs were limited due to the absence of data.