• 호남수학학술지
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• 제31권1호
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• pp.1-9
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• 2009

In this paper we establish strict lower bounds on number of sticks necessary to construct stick presentations of nontrivial or almost trivial ${\mu}$-curves.

• 호남수학학술지
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• 제30권1호
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• pp.165-170
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• 2008

We will examine the stick number of knots on the cubic lattice which is called the lattice stick number. The lattice stick numbers of knots $3_1$ and $4_1$ are known as 12 and 14, respectively. In this paper, we will show that only $3_1$ and $4_1$ have representations of irreducible non-trivial polygons, both numbers of whose sticks parallel to the y-axis and the z-axis are exactly four.

• Tribology and Lubricants
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• 제34권6호
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• pp.279-283
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• 2018

In this study, we investigate the behavior of abrasive particles and change of the stick-slip pattern according to chemical mechanical polishing (CMP) process parameters when a large number of abrasive particles are fixed on a pad. The CMP process is simulated using the finite element method. In the simulation, the abrasive grains are composed of those used in the actual CMP process. Considering the cohesion of the abrasive grains with the start of the CMP process, abrasive particles with various sizes are fixed onto the pad at different intervals so that stick-slip could occur. In this analysis, we determine that when the abrasive particle size is relatively large, the stick-slip period does not change as the pressure increases while the moving speed is constant. However, if the size of the abrasive grains is relatively small, the amount of deformation of the grains increases due to the elasticity of the pad. Therefore, the stick-slip pattern may not be observed. As the number of abrasive particles increases, the stick-slip period and displacement decrease. This is consistent with the decrease in the von Mises yield stress value on the surface of the wafer as the number of abrasive grains increases. We determine that when the number of the abrasive grains increases, the polishing rate, and characteristics are improved, and scratches are reduced. Moreover, we establish that the period of stick-slip increases and the change of the stick-slip size was not large when the abrasive particle size was relatively small.

• 소음진동
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• 제10권3호
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• pp.451-456
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• 2000

In this paper a discrete time model for the identification of nonlinear vibration system with stick-slip friction is proposed. The proposed model can handle the highly nonlinear behavior of the friction such as stick-slip phenomenon and Stribeck effect. The basic idea of the proposed model is as follows : If the nonlinearity of the system can be predicted as a simple function then this nonlinear function term cab be directly used in the discrete time model. By doing this the number of nonlinear terms in the model can be much less than those of NARMAX model which is widely used nonlinear discrete model. The simulation result shows that the proposed model can estimate the response of the nonlinear vibration system with stick-slip friction very well with less computational effort.

• 대한간호
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• 제34권2호
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• pp.45-57
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• 1995

A study .to identify an occupational hazards for hospital working health care providers from needle stick injury as an occupational hazards of health care providers in hospital and prevention A survey of 2430 health professionals (2184 nurses, 182 doctors, and 64 Lab technicians) was conducted to describe and provide information about 1) the experience of needle stick. 2) the number of needle stick, 3) the treatment after needle stick. 3) the situation of needle stick, 4) the report of needle stick, 5) the cause of needle stick, 6) the discard method of used needles, and 7) how to worry about getting infection disease after needle stick. Data were collected using questionnarires constructed by the authors and tested by a pilot study. Results of the study showed that 96.7% of the sample had an experience of needle stick (96.8% of the nurses, 96.7% of the doctors, and 92.2% of Lab technicians). Seventy seven percent of the sample experienced less than 10 needle sticks, 19% of the sample experienced 11 to 20 needle sticks, and the rest of the sample experienced more than 20 needle sticks. The situations where needle sticks occurred include intrvenous injection (36.5%), intramuscular injection (21.6%), blood withdraw (17.8%), and preparation(11.8%). The study showed that needle sticks (67.5%) usually occurred after client treatment. Health professionals used recapping method (55%) after they used needles. Needle sticks were predominantly caused by the carelessness of health professionals (61%), After needle sticks, 88.2% of the sample subjects treated needle sticks using disinfection technique by themselves. Most of health professionals (92.6%) did not report the accident. and 95.6% of them did not receive any test or further treatment. After needle sticks, 87.8% of nurses, 83.6% of doctors, and 96.6% of lab technicians worried about hepatitis infection. 'Health professionals also worried about AIDS infection, tetanus, venereal infection, and skin injury. These findings suggest that health professionals are at high-risk of needle stick and fail to report needle stick accidents. They should pay more attention to needle stick in order to avoid unwanted infection.

• 응용통계연구
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• 제23권4호
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• pp.767-776
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• 2010

Broken-Stick 모형 (Barton과 David, 1956) 하에서 순서화된 분절구간의 기대길이를 기초로 유효차원의 개수를 결정하는 Frontier (1976)방법은 일관된 모의실험 결과를 제공하는 기준 중의 하나로 보고된 바 있다 (Jackson, 1993). 이 연구에서는 Broken-Stick 모형(BSM) 하에서 분절구간길이의 분포를 이용하여 주성분 상대공헌도의 크기를 확률적으로 평가하는 BSM 유의확률기준을 제안한다. 이에 부가하여 소득분포의 불균등성을 도식화한 로렌츠곡선과 이에 대응하는 지니계수를 통해 주성분 공헌도의 포괄적 균등성을 탐구한다.

• EDISON SW 활용 경진대회 논문집
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• 제4회(2015년)
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• pp.491-495
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• 2015

Currently, selfie stick, a monopod take selfie photographs, got its popularity. Cradle used to connect selfie stick and smartphone usually uses electric force of spring to get smartphone fixed. But, using electric forces makes it hard to attach and detach smartphone from the cradle and gives possibility of smartphone falling down. CoQue suggests new solution of smartphone cradle by using cable tie (patent number US 8407863 B2) instead of electric force. It will give more easy and stable way of using selfie stick.

• 한국통신학회논문지
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• 제36권3B호
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• pp.287-296
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• 2011

시각장애인들이 주로 사용하고 있는 백색 지팡이(White Stick)는 지상의 부유장애물에 대한 감지가 어려울 뿐만 아니라, 보행중인 시각장애인에게 현재 위치정보와 응급상황 발생시 효과적인 보호 조치를 제공하는데 문제점이 있다. 본 논문에서는 이와 같은 문제점을 해결하여 시각장애인들이 보다 안전하고 편리한 보행을 할수 있는 사물지능통신(M2M : Machine-to-Machine) 기반의 지능형 보행보조시스템을 제안한다. 제안하는 시스템은 시각장애인이 사용하는 보행보조지팡이와 이동통신망을 통하여 다수의 보행보조지팡이 사용자를 원격 지원하는 서버로 구성된다. 보행보조지팡이는 초음파센서와 문자-음성 변환기술 등을 이용한 장애물 감지 및 인지 가능뿐만 아니라, 서버에서 제공하는 지리정보와 GPS(Global Positioning System) 수신 장치 등을 이용한 현재위치 알림 및 확인, 위급상황 대처 기능 등을 제공한다. 서버는 지리정보 제공뿐만 아니라, 보호자나 구호기관에 위급상황 발생위치 알림, 보행 동안의 주요 정보(장소 시간 및 횟수 등)를 제공한다. 제안 시스템의 시제품을 통한 기능 및 성능 시험 결과 만족스런 결과를 얻을수 있었다.

• Journal of Mechanical Science and Technology
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• 제15권9호
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• pp.1274-1280
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• 2001

The fretting wear behavior of the contact between Zircaloy-4 tube and Inconel 600, which are used as the fuel rod cladding and grid, respectively, in PWR nuclear power plants was investigated in air. In the study, number of cycles, slip amplitude and normal load were selected as the main factors of fretting wear. The results indicated that wear increased with load, slip amplitude and number of cycles but was affected mainly by the slip amplitude. SEM micrographs revealed the characteristics of fretting wear features on the surface of the specimens such as stick, partial slip and gross slip which depended on the slip amplitude. It was found that fretting wear was caused by the crack generation along the stick-slip boundaries due to the accumulation of plastic flow at small slip amplitudes and by abrasive wear in the entire contact area at high slip amplitudes.

• 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.