• Tribology and Lubricants
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• 제18권1호
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• pp.55-60
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• 2002

In many dynamic systems, there are unwanted oscillation which may arise the reduction of performance. Especially in low sliding speed condition, the stick-slip is an important issue because it because unstable motion as well as inaccurate position control in the system. Most previous works on the stick-slip are, however, only concerned with simple modeling under the condition of constant normal force. The normal force and the amount of hydraulic oil are variable with a cylinder stroke in the telescopic boom. This paper presents the pressure variations during stick-slip with the cylinder of telescope boom. Pressure variations by stick-slip has a similar pattern to that of single mass-spring model. The stick-slip is gradually decreased by means of increased flow rate.

• 한국컴퓨터그래픽스학회논문지
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• 제21권1호
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• pp.23-31
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• 2015

본 논문은 모션 캡쳐 데이터를 이용하여 쉽고 빠르게 사실적인 2차원 스틱 피규어애니메이션을 제작할 수 있는 방법을 소개한다. 스틱 피규어 애니메이션은 대개 전체 시간 구간에 대하여 매 프레임마다 하나씩의 자세를 일일이 그리는 방식으로 제작된다. 반면, 제안된 방법에서는 스틱 피규어 형태의 자세 위에 신체 부위의 움직임을 나타내는 동선을 추가하는 방식으로 한 장의 그림 안에 여러 프레임에 걸친 동작(예를 들어, 발차기나 점프)을 축약하여 표현하도록 한다. 이러한 그림으로부터 자동으로 시간에 따른 자세 변화를 합성하기 위하여, 먼저 사용자가 그린 스틱 피규어를 2차원 평면에서 변형시킬 수 있는 캐릭터 모델을 생성한다. 이 후, 미리 구축된 모션 데이터베이스로부터 주어진 자세 및 동작선 정보에 가장 근접한 동작 구간을 검색한다. 검색 결과로 추출된 동작에 따라 캐릭터 모델을 변형시킴으로써 최종적인 스틱 피규어애니메이션을 합성한다. 여러 형태의 스틱 피규어에 이동, 격투 등의 다양한 동작을 적용한 실험을 통하여, 제안된 방법이 적은 노력만으로 흥미로운 스틱 피규어애니메이션을 제작하는데 매우 유용함을 확인하였다.

• 한국항공운항학회지
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• 제17권1호
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• pp.58-63
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• 2009

The objective of this study is to analyze customer needs for the configuration of an aircraft cockpit layout of a single piston propeller aircraft. From the result of survey, we figure out the demand of the potential customers. We consider control stick and instrument out of several items to determine which pay for the aircraft or not. We analyze types and features of the aircraft control stick and the instrument which are equipped in the same aircraft in order to figure out what is best needed through a market survey and a questionnaire survey.

• 보존과학회지
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• 제28권2호
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• pp.165-173
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• 2012

본 연구에서는 고대 먹의 과학적이고 체계적인 분석을 통해 선조들의 조묵방법 및 기술을 파악하는 것이 연구의 목적이다. 고목재와 고문서의 묵서부의 먹을 분석한 결과 다음과 같은 결론을 얻었다. 고목재(창덕궁 신선원전 적심)를 연륜연대분석한 결과 1899년에 벌채된 것으로 나타났으며, 따라서 고목재에 씌어진 먹의 연대를 추정할 수가 있었다. 고대 먹 원료인 그을음의 단일입자크기는 고목재의 경우 평균 107nm로 가장 크게 분석되었고, 12개의 고문서의 경우 38~86nm범위를 나타냈다. 응집체입자크기 분석 결과 고목재의 경우 평균 370nm로 단일입자크기와 같이 가장 크게 분석되었으며, 고문서의 경우 평균 206~318nm로 분석되었고, 단일입자크기와 응집체입자크기 간에는 같은 경향의 분포를 나타내었다. 단일입자크기와 응집체입자크기로 그을음의 원료를 분석할 수가 있을 것으로 생각되었다. 고목재와 고문서 묵서부분의 박편상먹의 적외선 및 라만 분광분석에서는 목재나 종이의 간섭으로 먹 입자의 스펙트럼을 얻을 수 없었다. 고목재에서 분리한 분말먹의 라만 분광분석에서는 현대 송연 그을음과 유사한 라만 스펙트럼패턴을 보여, 송연먹으로 추정할 수 있었다.

• 기본간호학회지
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• 제14권2호
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• pp.166-172
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• 2007

Purpose: The purpose of this study was to examine the factors influencing glass particle contamination in single dose glass ampules upon opening. Method: The study was single case experimental design. Different methods of opening ampule (hand, wooden stick), different sizes of ampules(1cc, 2cc) and different sizes of needles(17gauge, 23gauge, $5{\mu}m$ filter) were evaluated. Eighteen ampules were randomly assigned in each group. The number of glass ampule particles ${\ge}10{\mu}m$ was counted by microscope. Results: There was no significant difference in the number of particles aspirated by opening methods. But number of glass particles was much lower when using 1cc ampules rather than 2cc ampules and was also much lower when using smaller size needles and needles which include a $5{\mu}m$ filter rather than larger size of needles. Conclusion: We suggest that larger bore or unfiltered needles increase the risk of aspirating more glass particles than smaller bore or filter needles. In addition, these data show that a wooden stick can be used as a method opening glass ampules.

• Asian Pacific Journal of Cancer Prevention
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• 제16권13호
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• pp.5579-5582
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• 2015

Background: Sale of single cigarettes is an important factor for early experimentation, initiation and persistence of tobacco use and a vital factor in the smoking epidemic in India as it is globally. Single cigarettes also promote the sale of illicit cigarettes and neutralises the effect of pack warnings and effective taxation, making tobacco more accessible and affordable to minors. This is the first study to our knowledge which estimates the size of the single stick market in India. Materials and Methods: In February 2014, a 10 jurisdiction survey was conducted across India to estimate the sale of cigarettes in packs and sticks, by brands and price over a full business day. Results: We estimate that nearly 75% of all cigarettes are sold as single sticks annually, which translates to nearly half a billion US dollars or 30 percent of the India's excise revenues from all cigarettes. This is the price which the consumers pay but is not captured through tax and therefore pervades into an informal economy. Conclusions: Tracking the retail price of single cigarettes is an efficient way to determine the willingness to pay by cigarette smokers and is a possible method to determine the tax rates in the absence of any other rationale.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.153-158
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• 1992

The purpose of this paper is to calculate the dynamic derivatives of single rotor Helicopter in forward flight. From trim condition, the equation of motion is derived, and we can calculate the dynamic dervatives. The results were compared with flight test data. The phase angle and stick displacement are obtained and compared at the trim condition.

• 한국소음진동공학회논문집
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• 제24권5호
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• pp.374-380
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• 2014

This article proposes a design guideline to reduce squeal noise generated by an automobile wiper blade. In order to explain the squeal noise phenomenon, a source of squeal noise is experimentally investigated using a rotating disk equipment, and then a single-degree-of-freedom stick-slip vibration model is established for a blade tip. Based on analytical results, we discuss a tendency of the squeal noise for various physical parameters.

• 전기학회논문지
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• 제65권2호
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• pp.335-341
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• 2016

In general, a yawing motion concept is used for the lateral control of one wheel robot where the gimbal system is located horizontally. In this paper, another concept of the vertically located gimbal system is presented for the same purpose. Although the vertical concept undergoes an instability more easily than the horizontal one, the pitching motion of the gyroscopic effect is considered. Firstly, the trade-off relation between two balancing concepts are investigated by comparing the gyroscopic mechanism. Secondly, the dynamic model for the problem of the proposed concept is derived using the oscillatory inverted stick model. Thirdly, the stability of the model is analyzed using the phase trajectory method. Finally, the control performance of the system by a vibration controller is simulated.

• 한국정밀공학회지
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• 제14권5호
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• pp.108-117
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• 1997

To prove the stability and the effectiveness of the robust non-linear friction control suggested and proved analytically in the previous paper, the describing function analysis is introduced. The instability of the Southward's nonlinear friction compensation for a digital position control and the improvement of phase margin of the robust nonlinear friction compensation are verified qualitatively through the describing function analysis. Those controls are applied to a single-axis digital servo driving experimental setup which has inherent stick-slip friction and experimental results confirm the results obtained in and the effectiveness of the robust nonlinear friction compensation for a digital position control.