• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 A
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• pp.61-63
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• 1999

This paper presents an efficient method for analysis of magnetodynamic system using frequency-dependent parameters. In equivalent electric circuit of linear magnetodynamic system, parameters of inductance and resistance are not constant since they vary with its driving frequency. Once frequency-dependent parameters of equivalent electric circuit for a given system are extracted, they can be used to analyze various characteristics of system. We use the Fourier transform, the high-order sensitivity method and Taylor series in order to efficiently extract the frequency-dependent parameters of magnetodynamic system. The proposed algorithm is applied to an induction heating system to validate its numerical efficiency.

• Journal of Information Processing Systems
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• 제7권1호
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• pp.93-102
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• 2011

In deeply scaled CMOS technologies, two major non-ideal factors are threatening the survival of the CMOS; i) PVT (process, voltage, and temperature) variations and ii) leakage power consumption. In this paper, we propose a novel post-silicon tuning methodology to scale optimum voltage and frequency "dynamically". The proposed design technique will use our PVT sensor circuits to monitor the variations and based on the monitored variation data, voltage and frequency will be compensated "automatically". During the compensation process, supply voltage is dynamically adjusted to guarantee the minimum total power consumption without violating the frequency requirement. The simulation results show that the proposed technique can reduce the total power by 85% and the static power by 53% on average for the selected ISCAS'85 benchmark circuits with 45 nm CMOS technology compared to the results of the traditional PVT compensation method.

• International Journal of Computer Science & Network Security
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• 제22권2호
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• pp.223-231
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• 2022

The application of computer software into the linguistic analysis of texts proves useful to arrive at concise and authentic results from large data texts. Based on this assumption, this paper employs a Computer-Aided Text Analysis (CATA) and a Critical Discourse Analysis (CDA) to explore the manipulative strategies of positive/negative presentation in Orwell's Animal Farm. More specifically, the paper attempts to explore the extent to which CATA software represented by the three variables of Frequency Distribution Analysis (FDA), Content Analysis (CA), and Key Word in Context (KWIC) incorporate with CDA decipher the manipulative purposes beyond positive presentation of selfness and negative presentation of otherness in the selected corpus. The analysis covers some CDA strategies, including justification, false statistics, and competency, for positive self-presentation; and accusation, criticism, and the use of ambiguous words for negative other-presentation. With the application of CATA, some words will be analyzed by showing their frequency distribution analysis as well as their contextual environment in the selected text to expose the extent to which they are employed as strategies of positive/negative presentation in the text under investigation. Findings show that CATA software contributes significantly to the linguistic analysis of large data texts. The paper recommends the use and application of the different CATA software in the stylistic and corpus linguistics studies.

• 정보교육학회논문지
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• 제10권2호
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• pp.261-271
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• 2006

정보통신기술 교육 운영지침이 2000년 8월에 발표된 이후 학교 현장에서 정보통신기술 교육이 실시되고 있다. 이에 따라 컴퓨터 교육과정에 대한 연구와 컴퓨터 교과서에 대한 비교 연구는 이루어졌지만 교사와 학생들의 컴퓨터 교과서 활용 현황과 그 관련 인식을 분석한 연구는 실시되지 않았다. 이에 본 연구는 충청북도 내 초등학교 5 6학년 담당 교사와 학생들을 대상으로 컴퓨터 교과서 활용 현황과 교과서의 구성 학습 내용 학습 활동에 관해 어떻게 인식하고 있는지를 알아보고, 교과서의 질적 개선을 위해 해결해야 할 과제를 제시하였다. 연구 결과, 대부분의 교사가 컴퓨터 교과서를 활용하고 있었으나 그 활용 빈도가 저조했고, 교과서를 그대로 활용하기 보다는 수정.보완하여 활용하고 있었다. 교사들은 교과서와 관련한 여러 영역 중에서 수준별 학습, 재구성 용이성, 체계성, 탐구력과 창의력 신장, 흥미유발, 자기주도적학습 능력 신장, 과제 제시 등에 대해 부정적인 인식을 가지고 있었다. 그에 비해 학생들은 용어에 대해서 부정적인 인식을 가지고 있었다. 개인 변인 중 교사는 주로 연령과 교직 경력에 따라서, 그리고 학생은 성별과 컴퓨터 교과서 활용 빈도에 따라서 유의미한 차이를 보였다.

• 한국컴퓨터정보학회논문지
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• 제22권11호
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• pp.49-55
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• 2017

Recently, for safety of people, there are proposed so many technologies which detect density of people at the specific place or space. The representative technology for crowd density estimation was using image analysis method from CCTV images. However, this method had a weakness which could not be used and which's accuracy was lower at the dark or smog space. Therefore, in this paper, to solve this problem, we proposed a user density estimation system at closed space using high frequency and smart device. The system send inaudible high frequencies to smart devices and it count the smart devices which detect the high frequencies on the space. We tested real-time user density with the proposed system and ten smart devices to evaluate performance. According to the testing results, we confirmed that the proposed system's accuracy was 95% and it was very useful. Thus, because the proposed system could estimate about user density at specific space exactly, it could be useful technology for safety of people and measurement of space use state at indoor space.

• International journal of advanced smart convergence
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• 제9권1호
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• pp.1-9
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• 2020

This study was conducted to investigate the effects of computer attitudes such as anxiety, confidence, preference, usefulness, and computer literacy on their critical thinking ability, targeting college students at unspecified university universities. The period of data collection was from January 10, 2020 to January 17, 2020. A total of 213 people participated in the study. For data analysis, SPSS 18.0 was used for frequency analysis, Pearson correlation, x2 square, and simple regression analysis. As a result of the analysis, the difference of interests under the statistical significance level among general characteristics was Gender (x²=55.7^***, p<0.001), Age (x²=407.5^***, p<0.001), Resident (x²=127.5^***, p<0.001) Family (x²=289.4^***, p<0.001). In the simple regression analysis, computer liking (t=2.102, p<0.05) and computer use ability affected Truth seeking (t=-6.319, p<0.01), computer use ability was affecting analyticity (t=-5.630, p<0.01), computer use ability was affecting systematicity (t=-2.545, p<0.05), computer use ability was affecting maturity under statistical significance (t=-2.583, p<0.05). In conclusion, this study suggests that computer liking and computer use ability affect the sub-factor components of critical thinking disposition, truth seeking, analyticity, systematicity, and maturity, therefore the emphasis of this study is to emphasize that it is desirable to use the computer as a medium of learning based on computer literacy rather than worrying about excessive computer use.

• 한국컴퓨터산업학회논문지
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• 제2권8호
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• pp.1063-1068
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• 2001

본 논문에서는 DDS 기법을 사용하여 광학음향효과 발생기의 고 정밀 6채널 DSB 변조기를 설계를 하였다. 또한 IEEE-488 인터페이스를 사용하여 다른 계측기와의 연동이 가능하도록 구성하였으며, DDS와 DAC의 제어를 위한 디바이스 드라이버를 80C51계열의 마이크로프로세서 어셈블러를 이용하여 작성하였다. 이러한 결과로 고 정밀 6채널 DSB 변조기는 기존의 변조기에 비해 주파수 가변 범위, 분해능, 스위칭 시간 등의 중요한 특성들이 개선되었으며, 이로 인해 정밀한 주파수 합성 시스템으로 사용이 가능할 것이라 예측된다.

• 한국컴퓨터정보학회논문지
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• 제23권6호
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• pp.51-58
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• 2018

This study was conducted to investigate the relationship between drinking, smoking, meat intake, and exercise. The participants were 1,060 males and females who voluntarily responded to the survey by visiting the health promotion booth at the H Festival held in C city in 2014. Research data were collected in interview form using questionnaires on alcohol use, smoking, exercise, and meat intake. The data were analyzed by descriptive analysis, cross tabulation analysis, multinominal logistic regression after stratification of gender using the SPSS 24 program. The results of the study are as follows: Smokers had a significantly higher frequency of drinking ($x^2=163.33$, p<.001) than non-smokers. Meat intake was high when alcohol use was high ($x^2=35.13$, p<.001). The risk rates for smoking, meat consumption, and exercise related to alcohol use are as follows. The smoking was higher as the frequency of drinking increased. For men, smoking OR(odd ratio) was 6.26 (p=.001) and for women, smoking risk OR was 16.82 (p=.002). Meats intake showed a higher OR as the alcohol use increased. The OR of almost daily ingestion of meat at frequent drinking days was 4.40 (p=.002) for males and 4.52(p=.009) for females. As the frequency of drinking increased, the OR of days of exercise tended to decrease. In men, the OR was 0.36 (p=.003), the lowest in the probability of exercising more than 5 days when drinking high. In the case of women drinking less than once a week, the OR was 0.43 (p=.027), which was the lowest for exercise for 5 days or more. In conclusion, the higher the frequency of drinking, the higher the smoking and meat intake, and the less exercise. If drinking, smoking, and meat intake are high but there is a lack of exercise, a chronic disease can occur and cause premature death unless there is a change in the new health behavior. The results of this study suggest researches to understand the motives related to alcohol abstinence, smoking cessation, dietary control and exercise, and to develop programs.

• 한국컴퓨터정보학회논문지
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• 제22권1호
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• pp.71-76
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• 2017

Recently, there are various researches using inaudible high frequencies like as wireless communication based smart devices, data transmission algorithm, indoor positioning trace technologies. However, when they use high frequencies of inaudible range, they have a problem that the accuracy of data transmission with high frequencies was low because of interference from ambient noise in our real life. To solve this problem, in this paper, we proposed an application based on smart phone and server system for collection of ambient noise and detection of robust high frequency range. The server system could detect the robust high frequency range from statistical analysis of collected noise and the robust high frequency could avoid interference from ambient noise. We tested the proposed application's ability to gather noise and high frequencies for a certain period of time to evaluate performance. According to the testing results, we confirmed that the proposed application and server system could detect a robust high-frequency range via noise analysis in real life. Therefore, the proposed application and server could be a useful technology for future research on inaudible high frequencies.

• Journal of Electrical Engineering and Technology
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• 제12권6호
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• pp.2342-2347
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• 2017

In this study, we design a reconfigurable frequency selective surface (FSS) using fluidic channels to use the FSS in multi-frequencies. Effective permittivity can be changed using water as the fluid of fluidic channels in a dielectric slab, and the frequency characteristics of FSS can be controlled. We optimize the dimensions of the fluidic channel to design a reconfigurable FSS and measure its transmission characteristics.