• The Journal of Korean Institute of Communications and Information Sciences
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• v.38C no.6
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• pp.503-511
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• 2013

This paper presents a speech enhancement method using non-negative matrix factorization. In training phase, we can obtain each basis matrix from speech and specific noise database. After training phase, the noisy signal is separated from the speech and noise estimate using basis matrix in enhancement phase. In order to improve the performance, we model the change of encoding matrix from training phase to enhancement phase using independent Gaussian distribution models, and then use the constraint of the objective function almost same as that of the above Gaussian models. Also, we perform a smoothing operation to the encoding matrix by taking into account previous value. Last, we apply the Log-Spectral Amplitude type algorithm as gain function.

• Transactions on Electrical and Electronic Materials
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• v.10 no.6
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• pp.222-226
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• 2009

The objective of this study is to share multimedia contents included in existing digital devices and to solve the problems of an increase in installation fees and non-environmentally friendly interiors. This study designed a new digital signal transmitter and receiver using power line transmission and HDMI in order to solve the problems in the existing systems. The transmitter and receiver designed in this study used an AD9867BCPZ PLC chip in which the transmission came from digital signals originating in a PC, and the system architecture was configured so that the outputs signals were connected to a TV from the receiver. The experiment was implemented by adding a Video Test Generator, a USBPre external sound card, and Smaart Live 6 for analyzing the characteristics of the configured system. In the video test results, it was verified that communication was actively implemented, and the image quality showed a constant level from the measurement of the captured video. In the case of the sound, it was verified that more than 90% of the sound signals were normally transmitted and received from the examination of their phases and magnitudes. Thus, the performance of the system designed in this study was verified, which leads to the resolution of some of the problems found in current digital devices.

• Korean Journal of Construction Engineering and Management
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• v.19 no.1
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• pp.12-20
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• 2018

Construction projects are often large in magnitude and high in construction amount. Therefore, construction activities have great impacts on business economics and social lives in the surrounding regional area. The residents can have public grievances if they are badly affected by the construction activities. Project owners should try to minimize adverse impacts in planning and design as well as in construction. The objective of this paper is to establish a public grievance breakdown structure and apply this breakdown structure to improving design functions in an effort to minimize public grievances. This research has been done in three steps of 1) analyzing the characteristics of public grievances in construction projects; 2) developing a public grievance breakdown structure; and 3) based on the public grievance breakdown structure, generating design alternatives that can improve the preparedness against public grievances. A case study has been done to demonstrate the applicability of the public grievance breakdown structure in generating design alternatives to minimize public grievances.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.6C
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• pp.601-606
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• 2005

Recently with the high expectation of voice over WLAN service, to supped fast inter-AP security transition in WLAN AP is one of the most actively investigating issues. It is also very important to minimize inter-AP security transition latency, while maintaining constantly the secure association from old AP when a station transits to new AP. Hence, this paper first defines secure transition latency as a primary performance metric of AP system in WLAN supporting IEEE802.11i, 802.1x, and 802.11f, and then presents low latency inter-AP security transition mechanism and its security FSM whose objective is to minimize inter-AP transition latency. Experiment shows that the proposed scheme outperforms the legacy 802.1X AP up to $79\%$ with regard to the transition latency.

• Korean Chemical Engineering Research
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• v.45 no.1
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• pp.93-102
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• 2007

The objective of this study is to develop a 3D DMFC model for modeling gas evolution and flow patterns to design optimal flow field for gas management. The gas management on the anode side is an important issue in DMFC design and it greatly influences the performance of the fuel cell. The flow field is tightly related to gas management and distribution. Since experiment for the optimal design of various flow fields is difficult and expensive due to high bipolar plate cost, computational fluid dynamics (CFD) is implemented to solve the problem. A two-fluid model was developed for CFD based flow field design. The CFD analysis is used to visualize and to analyze the flow pattern and to reduce the number of experiments. Case studies of typical flow field designs such as serpentine, zigzag, parallel and semi-serpentine type illustrate applications of the model. This study presents simulation results of velocity, pressure, methanol mole fraction and gas content distribution. The suggested model is verified to be useful for the optimal flow field design.

• Korean Journal of Agricultural Science
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• v.39 no.4
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• pp.555-559
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• 2012

Distillers dried grains with solubles (DDGS) is a by-product from processing corn to produce bio-ethanol, and it contains almost three times higher protein, fat, and fiber than corn. Intake of higher amount of nutrients originated from corn in lactating sows may contribute to changes in milk composition and thus alter the growth of suckling piglets. Therefore, the objective of this study was to evaluate effect of supplementing DDGS in the diet of lactating sows on variation in the body weight of piglets. A total of 50 sows with parities of 3 to 5 were usedand allottedinto one of four treatments which included 0 (CON), 10% (DDGS10), 20% (DDGS20), or 30% (DDGS30) DDGS in the diet. Diets were fed to sows during the whole lactation period. Individual body weights of piglets were measured within 24 h after farrowing and at weaning. No significant differences were observed inthe coefficient of variation (CV) for body weight of piglets within a litter after farrowing and at weaning among the treatments (p>0.05). There was, however, a tendency of decreases in the CV for body weight of piglets within a litter at weaning compared with that after farrowingin the DDGS10 and DDGS20 treatments. At weaning, the percentage of the number of piglets weighing less than 4.5 kg in DDGS20 (4.86%, 7 out of 144; p<0.05) or DDGS30 (5.04%, 6 out of 119; p=0.059) was lower than that in CON (12.41%; 17 out of 137) although this pattern was not observed in DDGS10. In conclusion, addition of DDGS in lactating sow diets improved piglet performance by reducing the number piglets weighing less than 4.5 kg.

• Biomedical Science Letters
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• v.22 no.3
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• pp.98-106
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• 2016

Investigation of human papillomavirus (HPV) in archival formalin-fixed paraffin-embedded (FFPE) material is important for understanding cervical carcinogenesis. The objective of the present study was to identify the high risk HPVs (HR-HPVs) using HPV E6/E7 mRNA testing from archival tissues in cervical cancer and the relation to HR-HPVs genotypes in paired cervical exfoliated cells. HPV E6/E7 mRNA testing and DNA chip testing were performed in 79 paired cervical FFPE tissues and exfoliated cells from women with histologically confirmed squamous cell carcinoma and adenocarcinoma. Overall agreement in HR-HPVs detection from FFPE samples and cytology samples were 98.5% in HPV 16, 100% in HPV 18, HPV 31, HPV 33, HPV 58, HPV 66, and HPV 68. Type-specific agreement between FFPE samples and cytology samples was 89.1% in HPV positive, 93.5% in HPV 16 and more than 70% in the other HR-HPVs. In conclusion, HR-HPVs were reliably detected in paired FFPE and cytology samples with some variation in type-specific detection.

• Korean Journal of Biological Psychiatry
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• v.14 no.2
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• pp.106-114
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• 2007

Objective : It is suggested that disturbance of dopaminergic system might be related to the possible mechanism of social phobia. The aim of this study was to investigate the possible association of DRD2 TaqI polymorphism and social phobia. Method : Fifty-one patients with social phobia and 200 comparison subjects were tested for DRD2 TaqI A polymorphism. The severity of social phobic symptoms was measured by self-report version of the Liebowitz Social Anxiety Scale(LSAS-SR) and Hamilton anxiety scale(HAM-A). Results : There was no signigicant difference in the genotype, allele frequency, A1 carrier frequency, and heterozygote frequency DRD2 TaqI A polymorphism between the social phobia patients and the control groups. However, we found significant decrease in somatic anxiety of the HAM-A in the patients having A2A2 homozygotes(p=0.014). In addition, patients having A1A2 heterozygotes showed more anxiety in two subscales (p=0.042 in anxiety, p=0.019 in performance) of the LSAS-SR. Conclusion : These results suggest that DRD2 A2 homozygote might have a protective role against somatic anxiety, and molecular heterosis of DRD2 TaqI A polymorphism might be related with more severe anxiety in social phobia.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.6 no.1
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• pp.39-58
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• 2011

The Study on the Influence of Selection factors of Franchise System and Franchisee's Satisfaction in the Food Service Franchise Industry. Franchisors can use franchisee selection criteria as a key input control to enhance the outcomes of their future franchisees. A business technique based on long term contractual arrangements between two legally independent businesses and relying on certain inputs from both parties for success and survival has significant potential for conflict. Furthermore,with many independent small businesses falling to reach their full potential, it is important to evaluate franchising as an alternative system of business management and to identify the characteristics of franchisor and franchisees which contribute to the satisfactory operation of a franchised small business. Thus, the objective of this study was to investigate a possible relationship between franchisee satisfaction and certain characteristics of the franchisor and of the franchisees themselves. In accordance with results of a hypothesis verification, a Selection factors of Franchise affects positively a Franchisee's Business Satisfaction.

• The Korean Journal of Community Living Science
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• v.28 no.4
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• pp.505-514
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• 2017

Although studies on the development of cool touch fabrics have been conducted widely, the effects of fitted pattern on enhancing the cooling sensation are insufficient. To investigate the effect of cool-touch fabric and fit of women's sports underwear, 3D and 2D patterns of sleeveless top and sports leggings were constructed. The performance of cool touch was tested by the Qmax value and wear test with nine subjects. Objective fit evaluation was observed by 3D virtual clothing using Clo software. Subjects rated wearing sensation such as 'cooling sensation, fit, wear comfort and preferences of purchase' using Likert's scale in the environmental chamber at $25^{\circ}C$, 45 %RH. The Qmax value of the cool touch fabric was higher than that of the PET fabric, which was well reflected in 'cooling sensation', especially in the case of a tight-fitted 3D pattern. The cooling sensation of the cool-touch fabric was not significantly elevated with 3D tight pattern as long as the size of the 2D pattern was similar to that of 3D pattern. However, the purchase preference was highly correlated with 3D fit and wear comfort.