• The Journal of the Acoustical Society of Korea
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• v.37 no.6
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• pp.483-488
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• 2018

Far field input utterance is one of the major causes of performance degradation of speaker verification systems. In this study, we used teacher student learning framework to compensate for the performance degradation caused by far field utterances. Teacher student learning refers to training the student deep neural network in possible performance degradation condition using the teacher deep neural network trained without such condition. In this study, we use the teacher network trained with near distance utterances to train the student network with far distance utterances. However, through experiments, it was found that performance of near distance utterances were deteriorated. To avoid such phenomenon, we proposed techniques that use trained teacher network as initialization of student network and training the student network using both near and far field utterances. Experiments were conducted using deep neural networks that input raw waveforms of 4-channel utterances recorded in both near and far distance. Results show the equal error rate of near and far-field utterances respectively, 2.55 % / 2.8 % without teacher student learning, 9.75 % / 1.8 % for conventional teacher student learning, and 2.5 % / 2.7 % with proposed techniques.

• Korean Journal of Construction Engineering and Management
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• v.15 no.5
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• pp.147-159
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• 2014

After 2008 global financial crisis, Korean housing market has experienced stagnation. So it caused housing market problems like housing price reduction, rising rent cost and so on. For housing market normalization government announced policies but Korean housing market didn't recover from stagnation. So, to understand why Korean housing market couldn't overcome the recession and why the policies didn't be effective, this research analyzed housing market participants (home owner, housing demand) based on the law of supply and demand and the psychological effect on their transaction intention based on behavioral economics(behavioral finance). Based on the analysis this research tested the effectiveness of announced policies using System Dynamics. The result showed that the amount of transaction and mortgage loan was influenced by the length of time to draft policies.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.10 no.3
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• pp.16-24
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• 2011

The vehicle electronic control system is being developed as the legal and social demand for ensuring driver's safety is rising. The various Driver Assistance Systems with various sensors such as radars, camera, and lasers are in practical use because of the falling price of hardware and the high performance of sensor and processer. In the preceding study of this research, the program was developed to recognize the experiment vehicle's driving lane and the cars nearby or approaching the experiment vehicle throughout the images taken by CCD camera. In addition, the 'dangerous driving analysis program' which is Vision System basis was developed to analyze the cause and consequence of dangerous driving. However, the Vision system developed in the previous studyhad poor recognition rate of lane and vehicles at the time of passing a tunnel, sunrise, or sunset. Therefore, through mounting the brightness response algorithm to the Vision System, the present study is aimed to analyze the causes of driver's dangerous driving clearly by improving the recognition rate of lane and vehicle, regardless of when and where it is.

• Journal of agriculture & life science
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• v.44 no.5
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• pp.137-146
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• 2010

The GyeongNam Province is one of the regions that have first introduced chrysanthemum farming in Korea since the 1960s. The chrysanthemum growers of The GyeongNam Province had strong competitiveness in production and marketing, so the their income ratios were relatively higher than any other growers of other provinces. The income ratio of The GyeongNam Province, however, has continuously decreased and stays currently below ratios of other provinces. The purpose of this paper is to find out which factors have contributed to the decrease in income ratio of GyeongNam Province. The analysis indicates that the increase in production cost was the main causes of rapid drop in income ratio. It is also worth mentioning that the income ratio falls dramatically when oil price (duty-free oil) rises above 700 won per liter.

• Journal of Service Research and Studies
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• v.8 no.4
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• pp.53-75
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• 2018

Bicycle-sharing as a product service system in the sharing economy, its characteristic is that users can go to nearby places by the public bike at any time however they don't need to have their own bicycle. However, the service quality of bicycle-sharing and satisfaction of users continuously decrease with the rapid growth number of bicycle-sharing users in China. Based on the double diamond model and from the perspective of service design, this research studies the service experience of bicycle-sharing of Chinese users, focuses on the potential pain points of Chinese users when using the public bike, and designs the optimum proposal to promote users' satisfaction. According to the research result, the research builds a new concept which can satisfy users' demand for communication, enjoyment and option during the cycling. The experience of new service system of bicycle-sharing makes humanized and subconscious interaction possible.

• Korean Journal of Social Welfare Studies
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• v.40 no.1
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• pp.87-114
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• 2009

Most previous studies on income inequality have limitations in reflecting recent changes and heterogeneity in women's working patterns and their family structure by regarding them as a homogeneous group. This study aims to investigate the trends of income inequality among women during the past 9 years since 1997 and to examine what is the most influential factor on these changes. The results show that the overall trend of income inequality among women is decreasing due to the income decrease of the middle class women and the income increase of the lower class. Among various factors, education, age, and marital status are key factors affecting inequality changes during this period. This study has the following policy implications: first, it is necessary to implement the child care services for the divorced and separated women, who are more likely to fall in poverty. Second, the increase of the basic pension benefits is needed particularly for the poor old women, who is more likely live longer in a desperate status.

• Environmental and Resource Economics Review
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• v.23 no.4
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• pp.583-615
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• 2014

Including the rolling black out in 2011, Korea has suffered from rapid increase of electricity consumption and demand forecasting failure for last five years. In addition, because of the Fukushima disaster, high fuel prices, and introduction of new generation sources such as renewables, the uncertainty on a power supply strategy increases. Consequently, a stable power supply becomes the new agenda and a revisino of strategy for new power generation sources is needed. In the light of this, we appraises the sixth basic plan for long term electricity demand and supply considering the changes of foreign and domestic conditions. We also simulate a strategy for the new power generation sources using a portfolio analysis method. As results, a diversity of power generation sources will increase and the share of renewable power generation will be surged on the assumptions of a cost reduction of renewable power sources and an increase of fuel costs. Particularly, on the range of a risk level(standard deviation) from 0.06 and 0.09, the efficient frontier has the most various power sources. Besides, the existing power plan is not efficient so that an improvement is needed. Lastly, the development of an electricity storage system and energy management system is necessary to make a stable and efficient power supply condition.

• The Journal of the Korea Contents Association
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• v.22 no.9
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• pp.531-543
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• 2022

This study aims to examine the mediating effects of ethical leadership and the moderating effects of organizational culture in relation to the impact of public service motivation on innovative behavior by public officials. This research utilizes data from the 2021 Public Employee Perception Survey conducted to public officials by the Korea Institute of Public Administration. Public service motivation had a positive effect on innovative behavior and ethical leadership, while ethical leadership had a positive effect on innovative behavior. In addition, ethical leadership mediated the relationship between public service motivation and innovative behavior. Under organizational culture, hierarchical and innovative cultures exhibited moderating effects. The policy and practical implications of these findings are as follows. First, it is important to build ethical leadership in order to retain the national competitiveness of public officials and encourage innovative behaviors that can adapt to changes at public organizations. Second, the competition rate for public service examinations has fallen recently. This may be interpreted as an unfavorable perception of public service bureaucracy among the MZ generation. Consequently, in line with the changing times, the organizations of public officials must adopt to a future-oriented, innovative culture. Third, it is necessary to explore alternative methods for developing an innovative culture, such as giving greater flexibility and autonomy through transfer of authority to public officials who address the public directly.

• Proceedings of the Korean Society of Computer Information Conference
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• 2013.01a
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• pp.9-12
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• 2013

리눅스 기반 안드로이드 단말에서는 CFS(Completely Fair scheduler)가 사용되고 있다. 그리고 CFS는 태스크의 nice값 조절을 통해서 응용프로그램의 CPU 점유율을 제어할 수 있다. 하지만 안드로이드를 업그레이드할 때마다 수많은 태스크의 nice값을 적절하게 맞추는 일은 매우 어려운 일이다. 이러한 문제를 해결하기 위하여 안드로이드 단말은 리눅스의 cgroup(control group)을 사용하여 태스크들을 그룹으로 나눈다. 고성능과 빠른 응답 특성이 필요한 태스크들을 apps 그룹에 할당하여 높은 CPU 점유율을 보장하고, 그렇지 않은 태스크들을 background 그룹에 할당한다. 하지만 안드로이드의 버전이 업그레이드 되면서 각 그룹에 속한 태스크들에도 변화가 생긴다. 그 결과 동일하게 제작된 태스크들의 CPU 점유율이 달라지게 되고 예기치 못한 성능 저하가 발생할 수 있다. 본 연구에서는 안드로이드 버전 향상에 따라 동종 태스크들이 이전 버전에서보다 성능이 하락하는 현상의 원인을 파악하였다. 아울러 분석과 실험을 통하여 태스크의 nice 값보다 그룹 스케줄링 메커니즘이 어떻게 태스크의 CPU 점유율을 결정 짓는지 규명하였다.

• Journal of Digital Convergence
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• v.10 no.10
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• pp.475-482
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• 2012

In recent years, visual media for Public Relations has become an important means to improve or change city images. The purpose of this study is to examine the relations between city images and images in visual media for PR. The results of this study would be provided as the fundamental data for making city's promotional video effectively.