• 제목/요약/키워드: Rotation degree

검색결과 384건 처리시간 0.031초

CNC 와이어 벤딩기 구동장치 개발 (Gear Train Development for CNC Wire Bending Machine)

  • 조현덕;최성종
    • 한국기계가공학회지
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    • 제7권4호
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    • pp.50-55
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    • 2008
  • CNC wire bending machines are used in industries to make a type variety of wire products such as long links. The machines have a long arm device to rotate in order to remove forming errors by flexibility of wire. Generally, the machines which constructed servo motors in the arm have the rotating range of the arm under 360 degree because the servo motors connect with fixed control devices on frame by many cables. The rotating angle under 360 degree limits working speed and forming geometry. Therefore this study developed a gear train to drive a parts in arm and to be independent on arm rotation movement. The developed gear train can transfer four movements to four components in arm and is consists parallel of four pairs of satellite gear trains. This study constructed the CNC wire bending machine with the developed gear train and verified that the gear train could drive internal components independently on arm rotation.

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HMD를 이용한 오디오 재생 기술에서 Latency의 영향 분석 (Effect on Audio Play Latency for Real-Time HMD-Based Headphone Listening)

  • 손상모;조현;김선민
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2014년도 추계학술대회 논문집
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    • pp.141-145
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    • 2014
  • A minimally appropriate time delay of audio data processing is investigated for rendering virtual sound source direction in real-time head-tracking environment under headphone listening. Less than 3.7 degree of angular mismatch should be maintained in order to keep desired sound source directions in virtually fixed while listeners are rotating their head in a horizontal plane. The angular mismatch is proportional to speed of head rotation and data processing delay. For 20 degree/s head rotation, which is a relatively slow head-movement case, less than total of 63ms data processing delay should be considered.

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척추측만증 치료를 위한 다양한 중재의 적용-사례연구 (The Effect of Various Interventions on an Adult with Scoliosis)

  • 최운호
    • 대한정형도수물리치료학회지
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    • 제17권2호
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    • pp.57-63
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    • 2011
  • Background: To investigate the effect of various intervention application on idiopathic scoliosis patient. Methods: One 20-years-old female subject underwent various intervention 3 times per week for 7 weeks. Modality physical therapy, muscle energy technique, combined pelvic tilt exercise and self exercise was performed for 50minutes. Degree of pain, axial trunk rotation, Cobb's angle, kyphotic angle, lumbar lordotic angle, and sacral angle were measured. Results: The subject decreased in degree of pan, axial trunk rotation, Cobb's angle, thoracic kyphotic angle, lumbar lordotic angle and sacral angle. Conclusions: The various interventions for scoliosis patients are effective in the pain and the improvement of angle on radiograph. However, any method is difficult to determine effective interventions.

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Thermodynamic and Kinetic Study on the Protonation of Free Base Tetraphenylporpyrin Derivatives in Solution

  • 유종완;유병수;정갑상;최호섭;유수창
    • Bulletin of the Korean Chemical Society
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    • 제19권4호
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    • pp.439-444
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    • 1998
  • The protonation of tetraphenylporphyrin (TPP) in acidic organic solutions was analyzed by acid titrimetric and temperature-dependent absorption measurements. Competition between the protonation of free base TPP $(TPPH_2)$ and the solvation of proton by near solvent molecules determines the equilibrium of the diprotonated TPP $(TPPH_4^{2+})$ formation. The diprotonated TPP exists as an ion pair complex with the acid counterions, which are found to affect the degree of red shift of the Soret band. The rotation of the phenyl rings also plays an important role in the diprotonation, as suggested by the decrease in the degree of diprotonation for the fluorophenyl TPP derivatives whose phenyl ring rotation is significantly hindered relative to normal TPP. The difference of fluorescence lifetime between $TPPH_2 \;({\pi}_{FL}=19.6\;ns)\; and\; TPPH_4^{2+} \;({\pi}_{FL}=2.1 \;ns)$ was used advantageously to measure the rate of protonation in the excited state. The protonation of TPPH2 are found to occur much slower than the diffusion of protons from bulk solution to the porphyrin ring. The monoprotonated TPP is suggested to be the transient species for the diprotonation process.

토릭소프트렌즈 피팅 시 축 회전과 각막난시와의 상관관계 (A Correlation between Axis-Rotation and Corneal Astigmatism in Toric Soft Contact Lens Fitting)

  • 박형민;김소라;박미정
    • 한국안광학회지
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    • 제19권2호
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    • pp.189-198
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    • 2014
  • 목적: 본 연구에서는 토릭소프트렌즈 피팅 시 회전방향 및 회전량과 각막난시도의 상관관계를 분석하였다. 방법: 20~30대, 전체난시 -0.75 D 이상의 직난시 114안을 대상으로 토릭소프트렌즈를 제조사의 가이드라인에 따라 피팅하고 정면주시 시와 응시방향을 달리하였을 때의 난시도와 회전방향 및 회전량과의 상관관계를 분석하였다. 또한 귀쪽과 코쪽으로 각각 $45^{\circ}$ 회전 시킨 후 회전복귀속도와 총 회전량을 각막난시도에 따라 비교 분석하였다. 결과: 각막난시도와 회전방향은 양의 상관관계를 나타내었으며, 각막난시도와 회전량 또한 양의 상관관계를 나타내었다. 한편, 응시방향에 따라 렌즈의 회전량이 상이하였으며 각막난시도와는 상관관계가 없었다. 각막난시도가 가장 높은 군에서 귀쪽과 코쪽으로 회전시킨 모든 경우에서 렌즈의 회전복귀속도가 가장 빨랐다. 결론: 토릭소프트렌즈의 최적의 축 안정화를 위하여 현재 전체난시만을 기준으로 처방되고 있는 피팅 가이드라인이 각막난시도를 고려하여 조정되어야 할 필요성이 있음을 제안한다.

만성요통환자의 요추부 불안정성 유무에 따른 능동 하지직거상 시 요골반부 회전각의 차이 (Comparison of Lumbopelvic Rotation Angle during Active Straight Leg Raise in Patients with Chronic Low Back Pain with and without Lumbar Segmental Instability)

  • 유창우;김선엽
    • 대한물리의학회지
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    • 제10권4호
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    • pp.39-48
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    • 2015
  • PURPOSE: This study aimed to compare the degree of lumbopelvic rotation during the active straight leg raise (ASLR) test in chronic low back pain with and without lumbar segmental instability. METHODS: A total of 71 patients with chronic low back pain were recruited for this study. The subjects who tested positive for more than three of the five lumbar segmental instability tests (prone lumbar instability, lumbar passive extension test, anterior posterior mobility test, passive straight leg raise, age) were categorized into the lumbar segmental instability positive group. Patients who tested positive for less than three of the five tests were categorized into the lumbar segmental instability negative group. The lumbopelvic rotation was measured three times during ASLR and a mean was determined. Subjective heaviness during the ASLR was measured on 6 point scale. RESULTS: There was a statistically significant difference in the lumbopelvic rotation angle between the groups with and without lumbar segmental instability (p<.01). There was no significant difference in the subjective heaviness during ASLR. The mean lumbopelvic rotation angle during ASLR was $13.54{\pm}2.86^{\circ}$, and $8.81{\pm}2.47^{\circ}$ in the positive and negative groups, respectively (p<.01). The cut-off value of the lumbopelvic rotation during was $10.5^{\circ}$, the sensitivity was 82.9%, and the specificity was 80.6%. CONCLUSION: These results suggest that lumbopelvic rotation is more prevalent in patients without lumbar segmental instability. Clinically, this important when diagnosing chronic low back pain with lumbar segmental instability, as the lumbopelvic rotation angle during the ASLR test can be used to aid in diagnosis.

프레임형 해양구조물의 보치환 기법에 관한 연구 (A Study on the Beam Permutation Technique for Frame Type Offshore Structures)

  • 박춘군;박한일
    • 한국해양공학회지
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    • 제13권1호통권31호
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    • pp.23-28
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    • 1999
  • For offshore structures, dynamic analysis becomes increasingly important as water depth increases and structural configuration becomes more slender. In the case of dynamic analysis of frame structures, much computer time and high cost are required due to many degrees of freedom, In this paper, a new technique of permutating a segment of frame structure to a beam is developed, which is called here Beam Permutation Technique. The technique is based on definition of stiffness matrix of the beam which is obtained by defining the actions(or forces) required to obtain unit translation or rotation for each degree of freedom wiht al other degree of freedom restrained to zero displacement or rotation. In the technique, an assumption is made that relative positions of nodes in the ends of the segment are not variable, The technique can significantly reduce the degrees of freedom of frame structures and thus the computiong time in dynamic analysis. The natural frequencies and static displacements of the permutated beam are obtained and compared to those of ANSYS with a good agreement.

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자동차용 광원의 광도분포 측정장치(배광측정기)제작 (Construction of a Distribution Photometer System for Automobile Light Sources)

  • 김용완;김홍기;이인원;이완순;이상원
    • 한국조명전기설비학회지:조명전기설비
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    • 제10권4호
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    • pp.53-61
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    • 1996
  • 광원에 대하여 서로 다른 여러 각도방향에서 광원을 바라볼 때 관측되는 광도 분포 및 재귀반사성능을 측정하기 위해 광도 분포 측정장치(배광측정기)를 제작하였다. 이 장치는 광원을 좌우로 360도, 상하로 $\pm$30도 회전 시킬수 있는 광원회전장치, 광검출기로 광전자증배관(PM Tube)을 쓰는 수광부 및 재귀반사성능 측정용 투광기와 제어 및 표시부로 구성되어 있다. 광도측정범위는 0.01~199900cd, 관측각범위는 0.2~1.5도 이고 광도의 측정오차는 $\pm$3%이다. 제작된 장치의 구조와 성능평가결과가 제기되었다.

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화면 움직임과 Cybersickness의 관계에 관한 연구 (Relationship between Scene Movements and Cybersickness)

  • 박경수;최정아;김경택;김상수
    • 대한인간공학회지
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    • 제24권1호
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    • pp.1-7
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    • 2005
  • This paper investigates the effects of scene movements on cybersickness to develop the guidelines of scene movements in virtual environments. The types of scene movements were made for both scene navigations(through the axes of X: lateral, Y: fore & after, and Z: vertical) and scene rotations(by pitch, roll and yaw). And there were each three levels of speed; 2.7, 4.5 and 6.3 /s(for navigation), and 10, 20 and 30 /s(for rotation) were conducted. Twelve participants were exposed to each scene for 15 minutes, and three tests were performed to measure the degree of sickness. Before and after subjects were exposed to virtual environments, they were requested to describe their sickness symptoms by means of answering the Simulator Sickness Questionnaire(SSQ). And the postural stability tests, in which the Center of Pressure(COP) of subjects were traced and recorded by a 'force platform', were conducted. During the exposure on virtual environments, the subjects were requested to rate the degree of nausea. For both navigation and rotation, the effects of speeds and axes were significant in the SSQ scores and the nausea ratings, while it was not in the COP. The correlation between the SSQ scores and the COP data was not found. Therefore, it was inappropriate to use COP as a measure of cybersickness. The degree of sickness increased, except for the case of the yaw, as the speed increased. The sickness was most severe in the scene navigation through the axis X and in the scene rotation by the yaw.

경부근막동통증후군 환자의 가동범위에 대한 연구 (The Effects of Joint Mobolization on Neck Myofacial Pain Syndrome)

  • 전호영;배성수
    • 대한물리의학회지
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    • 제2권1호
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    • pp.1-10
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    • 2007
  • Purpose : To identify the effects of Hold-Relax of proprioceptive neuromuscular facilitation (PNF) on the functional improvement of patients with neck myofascial pain syndrome. Methode : The present research investigated 60 patients with neck myofascial syndrome, dividing them into a group doing Hold-Relax of proprioceptive neuromuscular facilitation and a group doing Stretching, This study examined degree of recovery from neck pain by comparing their neck myofascial pain syndrome before and after the treatment, and compared two groups to find difference in the degree of recovery from myofascial pain syndrome. Results : 1. For Hold-Relax of proprioceptive neuromuscular facilitation group, the pain rating score (PRS) were significantly decreased for six weeks treatment. 2. For Stretching group, the pain rating score (PRS) did not indicate significant decrease for six weeks treatment. 3. For Hold-Relax of proprioceptive neuromuscular facilitation group, range of motion of flexion, left rotation, right rotation indicated significant difference after pre test and after two week but no significant difference after four week. 4. For Stretching group, range of motion of flexion, left rotation, and right rotation except extension indicated significant difference after pre test and after two week but no significant difference after four week. Conclusion : The Hold-Relax of proprioceptive neuromuscular facilitation is considered to be effective in increasing joint range of motion of patient and decreasing pain. Accordingly physical therapists has to learn a wide range of patterns and to develop various treatment techniques.

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