• 제어로봇시스템학회논문지
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• 제5권1호
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• pp.1-10
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• 1999

We consider the problem of synthesizing an internally stabilizing linear time-invariant controller for a linear tune-Invariant plant such that a given closed loop transfer function is strictly sector bounded. We show that the standard $H{\infty}$ control problem and the $\tau$ -positive real control problem are special cases of sector bounded control problem. Necessary and sufficient conditions for the existence of a controller are obtained. The state-space representation for strictly proper controllers are given in terms of solutions to ARIs or AREs.

• Kyungpook Mathematical Journal
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• 제51권1호
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• pp.77-85
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• 2011

In this paper, we introduce the integral operator $I_{\beta}$($p_1$, ${\ldots}$, $p_n$; ${\alpha}_1$, ${\ldots}$, ${\alpha}_n$)(z) analytic functions with positive real part. The radius of convexity of this integral operator when ${\beta}$ = 1 is determined. In particular, we get the radius of starlikeness and convexity of the analytic functions with Re {f(z)/z} > 0 and Re {f'(z)} > 0. Furthermore, we derive sufficient condition for the integral operator $I_{\beta}$($p_1$, ${\ldots}$, $p_n$; ${\alpha}_1$, ${\ldots}$, ${\alpha}_n$)(z) to be analytic and univalent in the open unit disc, which leads to univalency of the operators $\int\limits_0^z(f(t)/t)^{\alpha}$dt and $\int\limits_0^z(f'(t))^{\alpha}dt$.

• Asia Pacific Journal of Business Review
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• 제2권2호
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• pp.17-44
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• 2018

This study investigates whether the positive relation between the real earnings management (REM) and audit fees reported by Choi et al. (2016) differs before and after the Sarbanes-Oxley Act (SOX), and varies cross-sectionally depending on the existence of internal control problems. Using a large sample of U.S. firms, we find that the positive relation between REM and audit fees is stronger than the same relation between AEM and audit fees in the post-SOX period, whereas the opposite is true in the pre-SOX period. We also find that the positive relation between REM and audit fees is intensified for firms with material internal control weaknesses.

• 한국콘텐츠학회논문지
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• 제22권6호
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• pp.342-353
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• 2022

본 연구는 중국 현지의 학습자들을 대상으로 실시간 온라인 교육 플랫폼의 교수자 특성, 콘텐츠 특성과 플랫폼특성이 학습만족도 및 지속사용의도에 미치는 영향을 분석함으로써 실시간 온라인 교육 플랫폼 시장의 활성화에 도움이 되고자 한다. 설문조사를 통해 총 670부 설문지를 수집하여 실증분석을 실시하였다. 분석 결과, 첫째, 교수자의 특성인 매력성을 제외하고 전문성과 성실성은 학습만족도에 모두 유의미한 정의 영향관계가 있었다. 둘째, 콘텐츠 특성의 유용성, 풍부성과 적절성은 학습만족도에 모두 유의미한 정의 영향 관계가 있었다. 셋째, 플랫폼 특성인 상호작용성을 제외하고, 기술성과 편리성은 학습만족도에 모두 유의미한 정의 영향 관계를 확인하였다. 넷째, 학습만족도는 지속사용의도에 유의한 긍정적인 영향을 미쳤다. 따라서 실시간 온라인 교육 플랫폼 시장의 활성화를 위해 교수자 특성, 콘텐츠 특성과 플랫폼특성에 대하여 실제로 느끼는 효용의 가치를 높였다는 점에서 큰 의미가 있다. 본 연구는 실시간 온라인 교육 플랫폼 실무적 시사점과 향후 연구방향을 제시하였다.

• 소음진동
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• 제11권1호
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• pp.147-155
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• 2001

This paper is concerned with the real-time automatic tuning of the multi-input multi-output positive position feedback controllers for smart structures by the genetic algorithms. The genetic algorithms have proven its effectiveness in searching optimal design parameters without falling into local minimums thus rendering globally optimal solutions. The previous real-time algorithm that tunes a single control parameter is extended to tune more parameters of the MIMO PPF controller. We employ the MIMO PPF controller since it can enhance the damping value of a target mode without affecting other modes if tuned properly. Hence, the traditional positive position feedback controller can be used in adaptive fashion in real time. The final form of the MIMO PPF controller results in the centralized control, thus it involves many parameters. The bounds of the control Parameters are estimated from the theoretical model to guarantee the stability. As in the previous research, the digital MIMO PPF control law is downloaded to the DSP chip and a main program, which runs genetic algorithms in real time, updates the parameters of the controller in real time. The experimental frequency response results show that the MIMO PPF controller tuned by GA gives better performance than the theoretically designed PPF. The time response also shows that the GA tuned MIMO PPF controller can suppress vibrations very well.

• 대한인간공학회지
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• 제18권3호
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• pp.27-39
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• 1999

The purpose of this study was to approve the capability of human sensibility evaluation based on physiological responses and real-time subjective assessments. Three well-trained healthy human subjects were participated in the experiments. We measured physiological responses such as Heart Rate Variability(HRV), Galvanic Skin Response(GSR) and skin temperature under rest and visual stimulation conditions, respectively. Off-time subjective assessments were recorded before and after visual stimulations. Real-time subjective assessments were recorded during visual stimulations. The results of physiological responses and off-time and real-time subjective assessments were quantified and compared. The results showed that the correlation between physiological responses and real-time subjective assessments was high (83%) for both the positive and negative visual stimulation. The correlation between the physiological responses and off-time subjective assessments was high (83%) for the negative visual stimulation but was low (15%) for the positive visual stimulation. Although the current observation is preliminary and requires more careful experimental study, it appears that the correlation between real-time subjective assessment and physiological responses is higher than that of the off-time subjective assessment and physiological responses.

• 대한인간공학회지
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• 제20권1호
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• pp.31-43
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• 2001

The present study the feasibility of the new subjective assessment devise; Real-Time Subjective Assessment Digitizer (RTSAD). The subjects were instructed to evaluate their sensibility during the presentation of the positive and the negative visual stimuli using RTSAD. After the presentation of each of the stimulus, a questionnaire was used for comparing the results with those from RTSAD. It was argued that the biggest utility of the RTSAD is the capability of measuring and figuring out the trends of the subjective assessment in real time. The results from the questionnaires unlike the results from RTSAD, reflects only the averaged human sensibility for the entire time of the presentation of the stimulus.

• The Journal of Asian Finance, Economics and Business
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• 제3권2호
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• pp.5-11
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• 2016

This study investigates the impact of Malaysia's capital market and other key determinants on Economic Growth from the period of 1988 to 2012. The key determinants studied are foreign direct investment and real interest rate. This study also examines the long run and short run relationship between the economic growth and capital market, foreign direct investment, and real interest rate by using bound testing cointegration of Autoregressive Distributed Lag (ARDL) and Error Correction Model (ECM) version of ARDL model. The empirical results of the study suggest that there is long- run cointegration among the capital market, foreign direct investment, real Interest rate and economic growth. The result also suggests that capital market and real interest rate have positive impact on economic growth in the short run and long run. Foreign direct investment does not show positive impact on economic growth in the short run but it does in the long run.

• 대한수학회보
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• 제40권4호
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• pp.603-611
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• 2003

In this paper we extend the definition of K-positive definite operators from linear to Frechet differentiable operators. Under this setting, we derive from the inverse function theorem a local existence and approximation results corresponding to those of Theorems land 2 of the authors [8], in an arbitrary real Banach space. Furthermore, an asymptotically K-positive definite operator is introduced and a simplified iteration sequence which converges to the unique solution of an asymptotically K-positive definite operator equation is constructed.

• 대한수학회논문집
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• 제37권3호
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• pp.669-679
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• 2022

We provide a characterization of the positive monoids (i.e., additive submonoids of the nonnegative real numbers) that satisfy the finite factorization property. As a result, we establish that positive monoids with well-ordered generating sets satisfy the finite factorization property, while positive monoids with co-well-ordered generating sets satisfy this property if and only if they satisfy the bounded factorization property.