• Title/Summary/Keyword: Active Stick

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A study of an Active Stick Controlling System with Friction Observer (Active Stick 제어기 개발에 관한 연구)

  • Kim, Myung-Yul;Nam, Yoon-su
    • Journal of Industrial Technology
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    • v.24 no.B
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    • pp.207-214
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    • 2004
  • An active stick which supplies force feedback to the operator is developed in this study. A mathematical model of the active stick is derived, and compared with the experimental result. It turns out that the frictional torque due to the mechanical contacts of several parts of the stick is one of the major barriers to achieve high precision operation of the stick. The frictional effect of the stick is cancelled out by using a friction observer. The efficacy of the friction observer is verified through the numerical simulation. Because of the observer dynamics, there are some limitations in exact recovering the static friction and Stribeck effect. However, the friction observer follows the real friction on the average. It's anticipated that the application of the friction observer to the closed loop control of the active stick improves the performance of the displacement versus force characteristics, which will be proved experimentally in the further study.

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Active Stick Control using Frictional Torque Compensation

  • Nam, Yoonsu
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.90.6-90
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    • 2002
  • An active stick which has the variable force-feel characteristics is developed. A combined position and force control strategy is mechanized using a 2-axis built-in force sensor and LVDT. The 2-axis force sensor which measures the stick force felt by the operator is developed by using strain gages and appropriate instrumental amplifiers. A mathematical model of the active stick dynamics is derived, and compared with the experimental results. The frictional torque of the stick due to the mechanical contacts of several parts makes the experimental frequency responses to be dependent on the magnitude of excitation signal, and the precision closed loop control to be difficult. A friction observe...

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A Virtual Makeup Program Using Facial Feature Area Extraction Based on Active Shape Model and Modified Alpha Blending (ASM 기반의 얼굴 특징 영역 추출 및 변형된 알파 블렌딩을 이용한 가상 메이크업 프로그램)

  • Koo, Ja-Myoung;Cho, Tai-Hoon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.8
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    • pp.1827-1835
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    • 2010
  • In this paper, facial feature areas in user picture are created by facial feature points extracted by ASM(Active Shape Model). In a existing virtual make-up application, users manually select a few features that are exactly. Users are uncomfortable with this method. We propose a virtual makeup application using ASM that does not require user input. In order to express a natural makeup, the modified alpha blendings for each cosmetic are used to blend skin color with cosmetic color. The Virtual makeup application was implemented to apply Foundation, Blush, Lip Stick, Lip Liner, Eye Pencil, Eye Liner and Eye Shadow.

A Study on Performance-Analysis and Control of the Active Catheter (작동형 내시경의 성능 해석 및 제어에 관한 연구)

  • Cheong, J.P.;Kim, J.H.;Lee, J.M.
    • Proceedings of the KSME Conference
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    • 2000.04a
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    • pp.556-561
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    • 2000
  • This paper deals with the control of an active bending actuator fur a catheter. The bending actuator with 40mm in length utilizes three zigzag SMA (shape memory alloy) springs which are equally located in the circumference between inner $({\phi}2.5 mm)$ and outer $({\phi}3.0mm)$ tube. It is purposed on realization of desired bending angle $(90^{\circ})$ and direction $(360^{\circ})$. It is also installed in front of the catheter and used to guide a path at extremely bent or branched blood vessel. The performance-analysis of the bending actuator are investigated fur the purpose of optimizing the control of the bending actuator. The analog joy stick is used to command a bending angle and direction for the fast and accurate response. According to the commands of the joy stick, tensile force of each SMA spring is computed and obtained by controlling the temperature of each SMA spring using PWM (pulse width modulation) of supplied electric power.

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Needle Stick Injuries and their Related Safety Measures among Nurses in a University Hospital, Shiraz, Iran

  • Jahangiri, Mehdi;Rostamabadi, Akbar;Hoboubi, Naser;Tadayon, Neda;Soleimani, Ali
    • Safety and Health at Work
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    • v.7 no.1
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    • pp.72-77
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    • 2016
  • Background: This study aimed to determine the prevalence and factors related to needle stick injuries (NSIs) and to assess related safety measures among a sample of Iranian nurses. Methods: In this cross-sectional study, a random sample of 168 registered active nurses was selected from different wards of one of the hospitals of Shiraz University of Medical Sciences (SUMS). Data were collected by an anonymous questionnaire and a checklist based observational method among the 168 registered active nurses. Results: The prevalence of NSIs in the total of work experience and the last year was 76% and 54%, respectively. Hollow-bore needles were the most common devices involved in the injuries (85.5%). The majority of NSIs occurred in the morning shift (57.8%) and the most common activity leading to NSIs was recapping needles (41.4%). The rate of underreporting NSIs was 60.2% and the major reasons for not reporting the NSIs were heavy clinical schedule (46.7%) and perception of low risk of infection (37.7%). A statistically significant relationship was found between the occurrence of NSIs and sex, hours worked/week, and frequency of shifts/month. Conclusion: The study showed a high prevalence of NSIs among nurses. Supportive measures such as improving injection practices, modification of working schedule, planning training programs targeted at using personal protective equipment, and providing an adequate number of safety facilities such as puncture resistant disposal containers and engineered safe devices are essential for the effective prevention of NSI incidents among the studied nurses.

Effects of Active Vibration Exercise Using a Flexi-Bar on the Activity of Scapular Stabilizing Muscles: A Randomized Controlled Trial

  • Park, Chibok;Kim, Byeonggeun
    • Journal of International Academy of Physical Therapy Research
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    • v.11 no.1
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    • pp.1975-1980
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    • 2020
  • Background: It has been argued that changes in muscle activity in the upper trapezius and serratus anterior may or may not cause shoulder joint pain and dysfunction. Objective: To investigate the effects of active vibration exercise on muscle activity regarding scapular stabilization using a flexi-bar. Design: A randomized controlled trial. Methods: A total of 24 subjects were randomly assigned to a flexi-bar group with active vibration and general stick group with non-active vibration. Both groups performed the same four action programs for 6 weeks, three times a week for 30 minutes at a time. The upper trapezius muscle, middle trapezius muscle, lower trapezius muscle and serratus anterior muscle of the dominant side was measured by electromyography before and after the 6 weeks of exercise. The independent t-test and paired t-test were used to analyze data. Results: There was a significant difference between groups in upper trapezius muscle and serratus anterior muscle activity after exercise (P<.05). Also, there was a significant difference in upper trapezius muscle and serratus anterior muscle activity before and after exercise in the flexi-bar group (P<.05). Conclusion: This study demonstrates that active vibration exercise using a flexi-Bar contribute to reduce the activity of the upper trapezius muscle and promote the activity of the serratus anterior muscle.

Effect of Regular Physical Exercise on Physical Fitness Level in Nursing Students (규칙적인 운동이 간호대학생의 체력수준에 미치는 효과)

  • Cho Young-Hee
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.4 no.2
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    • pp.267-282
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    • 1997
  • This study was to test the relationship between regular physical exercise and physical fitness in nursing students. These subjects were 54 volunteers who agreed with intention of this study and were composed of 24 active group and 30 non-active group. The selected physical fitness tests were grip strength and back strength for measuring muscular strength, sargent jump and standing broad jump for measuring power, push-up, sit-up, and heart rate for measuring total endurance, reaction time and side step test for measuring agility, stick test and stork stand for measuring balance, and trunk flexion and trunk extension for measuring flexibility. The conclusion acquired was as follows : 1) Grip strength had significant difference between active group of $29.5{\pm}5.9kg$ and non-active group $25.4{\pm}7.2kg$(t=2.283, p=.027), and back strength between active group of $54.1{\pm}13.7kg$ and non-active group of $44.7{\pm}15.7kg$(t=2.310, p=.025), 2) Sargent jump was lower with non-active group($44.9{\pm}8.6cm$) than with active group($45.3{\pm}8.8cm$), however, was not significant(t=.182, p=.856). Standing broad jump was significantly lower with non-active group of $161.3{\pm}28.7cm$ than with active group of $191.4{\pm}27.0cm$(t=3.939, p=.000). 3) Push-up showed significant difference between active group of $25.3{\pm}12.3times$ and non-active group of $11.5{\pm}5.1times$(t=5.572, p=.000), and sit-up between active group of $21.8{\pm}7.4times$ and non-active group of $17.1{\pm}5.8times$(t=2.631, p=.011), and heart rate between actvie group of $110.5{\pm}12.8$beats/min and non-active group of $121.5{\pm}9.5$beats/min(t=-3.648, p=.001). 4) Reaction time was significantly higher with non-active group of $.300{\pm}.051sec$ than with active group of $.341{\pm}.041sec$(t=-3.285, p=.002). Side step test was lower with non-active group($8.8{\pm}1.1times$) than with active group($9.2{\pm}1.2times$), however, was not significant (t=1.309, p=.196). 5) Stick test showed not significant difference between active group of $25.8{\pm}14.8sec$ and non-active group of $30.7{\pm}17.9sec$(t=-1.058, p=.295), and stork stand between active group of $4.5{\pm}3.2sec$ and non-active group of $3.7{\pm}3.5sec$(t=.918, p=.363). 6) Trunk flexion came out not significant difference between active group of $14.2{\pm}5.0cm$ and non-active group of $15.8{\pm}7.3cm$(t=-.927, p=.358), and trunk extension between active group of $67.1{\pm}6.5cm$ and non-active group of $67.3{\pm}6.6cm$(t=-.140, p=.889). 7) Power was shown to be significantly related to total endurance(r=.717, p=.000 ; r-.739, p=.000). 8) Total endurance was shown to be significantly related to agility(r=-.752, p=.000 ; r=.684, p=.000 ; r=-.664, p=.000 ; r=.598, p=.002 ; r=.864, p=.000 ; r=-.536, p=.007). These results suggest that regular physical exercise is effective in promoting and maintaining physical fitness. As the further study, it is necessary to reinvestigate the effect with more refined design.

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Which Types of Dilemmas do Elementary School Teachers Experience and How do They Cope with in Science Classes? (초등교사는 과학 수업에서 어떠한 딜레마를 경험하고 어떻게 대응하는가?)

  • Yoon, Hye-Gyoung;Han, Moonhyun
    • Journal of Korean Elementary Science Education
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    • v.39 no.2
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    • pp.268-283
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    • 2020
  • In this study, we aimed to look at what dilemmas of science teaching elementary school teachers experience and how they cope with their dilemmas in everyday science classes. Three elementary school teachers participated and qualitative data such as class log, class video, and interview materials were analyzed in inductive ways. The main findings are as follows. First, the dilemmas were classified based on the four factors that make up the science class; teacher, student, learning content, environment. However the dilemmas appeared to be not only one factor involved, but the rest of the factors intertwined. Thus, it was interpreted how the main factors causing the dilemmas conflicted with other factors. Second, the types of teachers' coping strategies to the dilemmas could be largely divided into 'give-up', 'stick to' and 'modified'. In some cases, teachers gave up on what they valued and did not take active action ('give-up'), teachers chose what they valued and made decisions to actively realize it ('stick to'), and in others, conflicts were adjusted by introducing new methods or elements to their classes ('modified'). Based on these results, we discussed that the teacher's dilemmas could facilitate the teacher's learning or professional development.

An Experimental Study on Internal and External Negotiation for Trade Agreements

  • Sung, Hankyoung
    • East Asian Economic Review
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    • v.21 no.2
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    • pp.103-121
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    • 2017
  • This paper experimentally studies the performance of negotiation considering individual and party, like a country, share of benefit over the best ones. It experiments two-stage bargaining games, internal and external negotiations. From the experimental results, this paper shows strong tendency to select fair allocation in the internal negotiations, but the tendency would be weaker with attractive outside option. In addition, the outside option may claim difference in individual benefit. From the regressions on individual performance in the negotiations, being a proposing party would matter to enhance the performance. However, relative individual performance within party fairness matters. Still attractive no-agreement options happen to break the tendency. As policy implication for trade negotiation, this paper warns that possible loss in individual benefit from not active participation to the external negotiations, no active role of proposer in case that players stick to internal allocations, and deviation of advantageous sector due to attractive outside options.

Aesthetic Characteristics of the Ballerina Look Presented in Modern Fashion - Focused on the Design Since 1990 - (현대패션에 표현된 발레리나 룩의 미적 특성 -1990년 이후 디자인을 중심으로-)

  • 김선영
    • Journal of the Korean Society of Costume
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    • v.54 no.6
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    • pp.41-52
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    • 2004
  • The objective of this study is to contemplate both the formation and the aesthetic characteristics of the ballerina look represented in modern fashion by analyzing a ballet costume. The results of this study could be summarized as the following: the ballerina look is formed by ballet costume itself with being stick to or exposing human body line, or by casual dress mixed with a ballet costume; the materials consist of both the major materials for a ballet costume such as silk, chiffon, tulle, lace, or organza, and the usual materials for casual dress: a variety of color such as transparent, pastel etc. is also used with typically used colors like white and black: decoration is basically composed of ruffle, drape, gather and the distinctive accessory like toe shoes, ribbon tape, ankle warmer is used to show a feature of a ballet costume These formative characteristics of the ballerina look presented in modern fashion implies illusory, pure, and hybridity. traits. First, illusion of the ballerina look not only implicitly expresses a womans wish to experience a ballerina's fantastic world, but also recreates woman herself into a ballerina on a stage. Second, purity of the ballerina look makes design look feminine and smooth, which is expressed with girlish taste through materials and colors. Third, hybridity of the ballerina look suggests a standard of a new trend, which is active style, by adding comfortableness and flexibleness to romantic femininity.