• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.109-109
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• 2004

구조물에 있어서 진동은 소음을 유발하며 구조물을 불안정하게 만드는 요인이 된다. 특히, 저주파 진동은 구조물에 미치는 영향이 크므로, 유연구조물의 저주파 진동모드들을 우선적으로 제어할 필요가 있다. 본 논문에서는 압전세라믹을 작동기로, 압전필름을 감지기로 사용하였고, 능동 제어 알고리즘의 하나인 적응형 디지털 PPF(Positive Position Feedback) 제어기를 구성하여 유연 외팔 평판과 열린 박스 구조물에서 저주파 진동을 감소시켰다.(중략)

• Proceedings of the Safety Management and Science Conference
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• 2011.04a
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• pp.19-28
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• 2011

This paper reviewed the relationship between job characteristics and incremental innovation, and the moderating effect of tenure. The results of multiple regression analysis, based on the responses from 241 employees in service industry, showed that job variety, identity, importance, autonomy and feedback have positive relationships with incremental innovation. In moderating effects, tenure interacts with variety and identity to have positive effects on incremental innovation, but tenure interacts with job importance, autonomy and feedback to have negative effects on incremental innovation.

• Bulletin of the Korean Chemical Society
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• v.10 no.5
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• pp.452-458
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• 1989

The static and dynamic phenomena of a model for the metabolic control system with positive feedback are discussed with the static and dynamic renormalization group theory. Then, the explicit results for the static and dynamic exponents are obtained up to the second order of ${\varepsilon}$-expansion, ${\varepsilon}$ being 4-d, where d is the space dimensionality of the system.

• Bulletin of the Korean Chemical Society
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• v.11 no.6
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• pp.557-560
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• 1990

The transition from one stable steady state branch to another stable steady state branch in a simple metabolic system with positive feedback is discussed with the aid of the bimodal Gaussian probability distribution method. Fluctuations lead to transitions from one stable steady state branch to the other, so that the bimodal Gaussian evolves to a new distribution. We also obtain the fractional occupancies in the two stable steady states in terms of a parameter characterizing conditions of the system.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.4
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• pp.1707-1710
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• 2014

Background: The objective of this study was to evaluate baseline use and positive rates of staging images (bone scan, CT) in newly diagnosed patients with prostate cancer (PCa) and to improve staging image overuse. Materials and Methods: This retrospective study covered a consecutive series of patients with PCa who underwent stage imaging at our institution between 2006 and 2011. Various clinical and pathological variables (age, PSA, biopsy Gleason score, clinical T stage, positive biopsy core rate) were evaluated by multivariate logistic regression analysis for their ability to predict a positive staging image. All patients were stratified according to the NCCN risk stratification and positive rates were compared in each risk group. Results: 410 patients (100%) underwent a bone scan and 315 patients (76.8%) underwent a CT scan. Some 51 patients (12.4%) had a positive bone scan, clinical T3 and T4 being significant independent predictors. Positive bone scan rates for low-, intermediate-, high-, and very high-risk groups were 0%, 0%, 8.25%, and 56.6%. Some 59 (18.7%) patients had a positive CT scan, with elevated PSA and clinical T3, T4 as significant independent predictors. Low-, intermediate-, high- and very high-risk group rates were 0%, 0%, 13.8% and 80.0%. Conclusions: The incidences of positive staging image in low- and intermediate- risk group were reasonably low. Following feedback on these results, staging in low- and intermediate- risk groups could be omitted.

• English Language & Literature Teaching
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• v.16 no.1
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• pp.171-188
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• 2009

The purpose of this study was to investigate the role of ongoing feedback from the professor in students' processes of learning and developing writing skills. Specifically, the researcher was concerned with how ongoing feedback affected students' attitudes towards writing because in EFL contexts, motivating students to write is a first step to engage them in a challenging journey of academic writing. 20 freshmen taking a writing course, "Paragraph & Essay Writing", at A university participated in this study and they were asked to complete the questionnaire at the end of the spring semester 2009. The results revealed that receiving ongoing feedback from the professor had a positive influence on affective domain, was helpful to develop learning strategies, and was valuable in learning outcomes. However, they also expressed negative opinions: feeling a burden, focusing on forms, and feeling confused. To reflect their opinions, the following four suggestions were made to create a more effective learning environment: promoting learner autonomy, facilitating individual writing conferences, giving balanced feedback in between form and content, and using judicious feedback through careful streaming.

• ETRI Journal
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• v.36 no.6
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• pp.979-987
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• 2014

This paper describes new tactile feedback patterns and the effect of their input performance for a button GUI activated by a tap gesture on mobile touch devices. Based on an analysis of touch interaction and informal user tests, several tactile feedback patterns were designed. Using these patterns, three user experiments were performed to investigate appropriate tactile feedback patterns and their input performance during interaction with a touch button. The results showed that a tactile pattern responding to each touch and release gesture with a rapid response time and short falling time provides the feeling of physically clicking a button. The suggested tactile feedback pattern has a significantly positive effect on the number of typing errors and typing task completion time compared to the performance when no feedback is provided.

• Journal of KSNVE
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• v.7 no.6
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• pp.1007-1013
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• 1997

This paper presents active vibration control scheme of multi-mode forced vibration using piezocetamic sensors and actuators. The control scheme adopted is the Positive Position Feedback (PPF) control. Among various vibration control techniques. PPF control technique makes use of generalized displacement measurements to accomplish the vibration suppression. Two independent controllers are implemented to control the first and the second modes of the beam under external excitation. Experimental results for various damping ratios and feedback gains of the PPF controllers are compared with respect to the contorl efficiency. The results indicate that steady state vibration under wide band excitation can be controlled effectively when multiple sets of PZT sensors and actuators were used with PPF control technique.

• Korean Journal of Child Studies
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• v.22 no.1
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• pp.147-162
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• 2001

This study examined the relation between mother-child verbal interaction strategies and children's narrative competence. Forty-eight 4-year-old middle class children(25 girls and 23 boys) and their mothers were observed in their homes. All the children were asked to produce a new story. Mothers used more descriptive statements and questions, more inferential questions and more evaluative questions than children. Children gave more answers and used more negative feedback than mothers. Mother's use of high-mental demanded question and positive feedback strategies were positively correlated with children's level of narrative structure. Mothers' use of inferential and evaluative questions were positively correlated with narrative length. Children's use of high-mental demanded statements and positive feedback strategies were positively correlated with their level of narrative structure and their use of descriptive and high-mental demanded strategies were positively correlated with narrative length.

• Korean System Dynamics Review
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• v.10 no.4
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• pp.39-51
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• 2009

In this paper, we constructed a cognitive map of President Lee of Korea on the policy vision of green growth. This cognitive map is characterized by a scarcity of feedback loops and a strong emphasis on the positive loops. These characteristics can be understood by the fact that the green growth policy is to overcome the limits to growth coming from negative feedback loops. As a conclusion, we proposed a negative feedback loop approach to the green growth policy vision, which might minimize the side effects of positive loops.