• Title/Summary/Keyword: Base position

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COMPARISON OF CRANIAL BASE MORPHOLOGY BETWEEN THE MANDIBULAR PROGNATHISM AND MAXILLARY RETROGNATHISM IN SKELETAL CLASS III PATIENTS (하악과성장형과 상악열성장형 골격성 Ⅲ급 부정교합군간의 두개저 형태 비교)

  • Kang, Dong-Hwa;Kwon, Tae-Geon;Lee, Sang-Han;Kim, Hyun-Soo
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.33 no.3
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    • pp.204-210
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    • 2007
  • This study was intended to compare the cranial base morphology between the mandibular prognathism and maxillary retrognathism in skeletal class III patients. The subject of the present study was composed of 88 patients divided into two groups; Group 1 (Skeletal Class III with mandibular prognathism. SNA within normal range, SNB over normal range, n=54) and Group 2(Skeletal Class III with maxillary retrognathism. SNA below normal range, SNB within normal range, n=34). Lateral cephalogram were taken immediate before surgery and 18 landmarks were used to analyze the characteristics of cranial base and maxillomandibular skeleton. The result revealed that cranial base angle is significantly smaller in Group 1 than Group 2, which implies the influence of the cranial base angulation on the mandibular position. However the posterior cranial base length did not influence the mandibular horizontal position and anterior cranial base length did not influence the maxillary horizontal position. As the anterior cranial base length was closely related with ramal height, it is recommendable to investigate the regulatory mechanism of chondrogenesis of cranial base and condyle cartilage in the future research.

Insight into Rhodopsin Diversity from Viewpoint of Counterion

  • Terakita, Akihisa
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.33-36
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    • 2002
  • In vertebrate rhodopsins the glutamic acid at position 113 serves as a counterion to stabilize the protonated retinylidene Schiff base linkage and to shift the spectrum to the visible region. Invertebrate rhodopsins and retinochrome have the amino acid residue different from glutamic acid or asparatic acid at this position and therefore, these pigments may have a counterion at different position. We first investigated the counterion in retinochrome by site specific mutagenesis. The results showed that the counterion is the glutamic acid at position 181, where almost of all the pigments including vertebrate and invertebrate rhodopsins in the rhodopsin family have a glutamic acid or an aspartic acid. In vertebrate rhodopsins, however, Glu 181 does not act as a counterion, and the red-sensitive cone pigments have a histidine at this position, which serves as a chloride-binding site for red-shift of the absorption spectrum. These findings suggested that the role of Glu181 as a counterion may be weakened by the newly acquired counterion at position 113. Taken together with our recent studies on an invertebrate-type rhodopsin, the rhodopsin diversity was discussed from viewpoint of counterion.

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The Influence of Foot Position on Standing Balance on an Unstable Base of Support

  • Lee, Jun Cheol
    • International Journal of Internet, Broadcasting and Communication
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    • v.10 no.2
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    • pp.84-94
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    • 2018
  • The purpose of this study was to compare the balance ability at different foot positions using K A T 2000 (Berg, Inc, vista, CA.1994). Thirty (male 15, female 15) normal subjects participated in this study. All subjects were tested at a one leg position or a two leg position that were toe-in $25^{\circ}$, toe-out $25^{\circ}$, and $45^{\circ}$. The starting position was where the subject crossed their arms across the chest and flexed knees slightily. The results of each test were displayed on a screen in a score format, which indicated balance index. These collected data were analyzed by using one way ANOVA, and t-test. The results of this study were as follows: When changing the angle of the foot in the one-foot and two-foot standing positions, there was no statistically significant difference, but the balance performance with the foot rotated by $25^{\circ}$ was better than that with the foot rotated by $45^{\circ}$. When changing the direction of the foot in the one-foot and two-foot standing positions, there was no statistically significant difference, but the balance performance with the foot rotated laterally was better - except for the case when the foot was medially rotated by $25^{\circ}$ in the right-foot static standing position. When the feet were medially rotated by $25^{\circ}$ in the two-foot static standing position, and were medially rotated by $25^{\circ}$ and $45^{\circ}$ in the one-foot static standing position, the balance performance of females was better than that of males. In this study, it was found that the balance performance of the subjects changed when the position of the foot was shifted on an unstable base of support. However, there was little correlation between balance performance and the height, weight and foot length of the subjects. It is necessary to conduct a follow-up study targeting various age groups and those with various diseases using an unstable platform or applying different physical or visual conditions, such as the length of the legs. Physical therapists need to consider the position of the foot in clinical settings for a better balance training or assessment.

The Correlation of the Area of the Base of Support with the Maximal Voluntary Isometric Contraction of Upper Limb Muscles (기저면의 넓이와 상지 근육의 최대 수의적 등척성 수축의 상관관계)

  • Lee, Sang-Yeol;Jo, Marg-Eun
    • PNF and Movement
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    • v.14 no.1
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    • pp.49-52
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    • 2016
  • Purpose: The purpose of the present study was to examine the effects of the area of the base of support formed by the human body on the maximal voluntary isometric contraction of upper limb muscles. Methods: The study was conducted with 20 normal adults. To identify changes in the base of support, the maximal voluntary isometric contraction of the biceps muscle was measured in a standing position, a sitting position, and a lying position for each subject. The sizes of the base of support formed in the standing, sitting, and lying positions were set to 1, 2, and 3 respectively, based on the sizes, to analyze the correlations. The maximal voluntary isometric contraction of the biceps muscle was measured using surface electromyograms (EMGs) (Noraxon DTS, Germany). Results: The results showed negative correlations in which, as the size of the base of support increased, the maximal voluntary isometric contraction of the biceps muscle decreased. Conclusion: Changes in the base of support of the body affect the maximal voluntary isometric contraction of the upper limbs. Therefore, when resistance exercises are applied for muscle strengthening, the positions should be changed considering the changes in muscle activity according to those positions. In addition, when EMGs are used to measure the maximal voluntary isometric contraction, the measurements should be conducted in the same positions, considering muscle activity that changes according to the base of support and positions, for data quantification.

Sub-micron Control Algorithm for Grinding and Polishing Aspherical Surface

  • Kim, Hyung-Tae;Yang, Hae-Jeong;Kim, Sung-Chul
    • International Journal of Control, Automation, and Systems
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    • v.6 no.3
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    • pp.386-393
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    • 2008
  • A position control method for interpolating aspherical grinding and polishing tool path was reviewed and experimented in a nano precision machine. The position-base algorithm was reformed from the time-base algorithm, proposed in the previous study. The characteristics of the algorithm were in the velocity control loop with position feedback. The aspherical surface was divided by an interval at which each velocity and acceleration were calculated. The theoretical velocity was corrected by position error during processing. In the experiment, a machine was constructed and nano-scale linear encoders were installed at each axis. Relation between process parameters and the variation of position error was monitored and discussed. The best result from optimized parameters showed that the accuracy was 150nm and improved from the previous report.

In Base-station with Multi-channels Using the Second Law of Cosines the Position Estimation Method (다채널을 가진 기지국에서 코사인 제2법칙을 사용한 위치 추정 방법)

  • Lee, Hyun-Sung;Bok, Young-Su;Shin, Hye-Jung;Park, Byung-Woo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.12B
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    • pp.1387-1398
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    • 2009
  • In the latest we will make a demand for the precision position estimation for the Mobile-station(MS)'s position. But, we have a lot of problems the position estimation method using the existing method. The Base-station(BS) measure a distance according to time delay waves to receive propagate from the MS and estimate the position using the existing circle equation with method to be selected BSs in close proximity the MS. It knows that happens a lot of error the estimated position and the true position. This paper propose that the method is selected round BSs to estimate for MS's position and estimated the angle using the second law of cosine. This paper demonstrate that using simulation the proposal method is a predominant method to compare with the existing method.

THE CORRELATION BETWEEN CRANIAL BASE SIZE, SHAPE AND HEAD POSTURE, AND THE POSITION OF MAXILLO-FACIAL STRUCTURES (두개저의 크기, 형태 및 두부자세와 악안면구조의 위치적 상관관계)

  • Hong, Yong-Seok;Yoon, Young-Jooh;Kim, Kwang-Won
    • The korean journal of orthodontics
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    • v.27 no.5 s.64
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    • pp.743-760
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    • 1997
  • This study was done to evaluate the correlations between the size, the form of the cranial base, head posture and the horizontal and vertical position of craniofacial structures. For this purpose, 100 cephalometric radiographs were taken from the sample composed of 51 male and 49 female, 12 measurement criteria and 37 reference points were established and digitized, then calculation was performed for the values of measurement variables and the horizontal and vertical position of reference points. The correlations be4ween them were analyzed statistically and mean facial diagrams were constructed and compared with the selected groups which were composed of 10 Samples each as large and small group from the measurement value. The following results were obtained: 1. The angles n-s-ba and n-s-ar as variables for the ion of cranial base correlated highly to the horizontal and vertical position of reference points in the cervical column with statistical significance($0.1\%$ level). 2. The angles n-s-ba and n-s-ar as variables for the form of cranial base correlated to the horizontal position of the reference points in the facial structure with statistical significance($1\%$ level), but not to the vertical position of them($5\%$ level). 3. The length n-s, s-ba, and n-ar as variables for the size of cranial base were correlated th the position of craniofacial structures in various ways, but in general, highly correlated to the horizontal and vertical position of midfacial structures around the teeth and alveolar area. 4. the angle NSL/CVT and NSL/OPT as postural variables tot the inclination of cranial base and cervical column were correlated to the horizontal position of the craniofacial structures with statistical significance($1\%$ level), but not to the vortical position of them($5\%$ level). 5. The angle OPT/HOR and CVT/HOR as postural variables lot the inclination of cranial base and true horizontal line were not correlated to the horizontal and vertical position of the craniofacial structures with statistical significance($5\%$ level). 6. The correlation between the measurement variables and horizontal and vortical positions of the reference poits in soft tissue were shown as similar to the related hard tissue points.

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A STUDY ABOUT CLINICAL APPLICATION OF GROWTH CHANGES IN SAGITTAL JAW RELATION AND INCISOR POSITION (상하악 전돌상태와 상하악전치위치의 성장변화에 대한 임상적 응용에 관한 연구)

  • Kang, Goo Han;Kim, Il Bong
    • The korean journal of orthodontics
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    • v.12 no.1
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    • pp.27-30
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    • 1982
  • The growth changes in position of upper and lower jaws, incisal inclination in relation to inferior cranial base have been described. Twenty five males was studied quantitavely by means of serial cephalometric reontgenogram from seven to thirteen years of age. The findings seem to warrant the following conclusions: 1. Growth change in anteroposterior relationship of upper and lower jaws to the anterior cranial base showed very little change before eleven years of age but axial inclination of incisal teeth tended to become labiaization in relation to the anterior cranial base. 2. kiter eleven years of age, there wasn't nearly labialization of incisal teeth but jaw prognathism occurred a little in relation to the anterior cranial base.

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The Analysis of Motion Error in Scanning Type XY Stage (스캐닝 방식 XY 스테이지의 운동오차 분석)

  • 황주호;박천홍;이찬홍;김동익;김승우
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2004.10a
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    • pp.1380-1383
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    • 2004
  • The scanning type XY stage is frequently used these days as precision positioning system in equipment for semiconductor or display element. It is requested higher velocity and more precise accuracy for higher productivity and measuring performance. The position accuracy of general stage is primarily affected by the geometric errors caused by parasitic motion of stage, misalignments such as perpendicular error, and thermal expansion of structure. In the case of scanning type stage, H type frame is usually used as base stage which is driven by two actuators such as linear motor. In the point view of scanning process, the stage is used in moving motion. Therefore, dynamic variation is added as significant position error source with other parasitic motion error. Because the scanning axis is driven by two actuators with two position detectors, 2 dimensional position errors have different characteristic compared to general tacked type XY stage. In this study 2D position error of scanning stage is analyzed by 1D heterodyne interferometer calibrator, which can measure 1D linear position error, straightness error, yaw error and pitch error, and perpendicular error. The 2D position error is evaluated by diagonal measurement (ISO230-6). The yaw error and perpendicular error are compensated on the base stage of scanning axis. And, the horizontal straightness error is compensated by cross axis compensation. And, dynamic motion error in scanning motion is analyzed.

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Stereoscopic Operators and Their Application

  • Gruts, Yu.-N.;Son, Jung-Young;Kang, Dong-Hoon
    • Journal of the Optical Society of Korea
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    • v.5 no.3
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    • pp.90-92
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    • 2001
  • Direct and inverse mathematical operators of stereo transformation (stereo operators) are studied in this paper. The stereo operators install a one-to-one correspondence between three dimensional coordinates of any point in space and the stereo coordinates which can be displayed on the screen under the given conditions, i.e. stereo vision base and the position of viewer. The stereo operators can be applied to the analyses of stereoscopic image distortions when the stereo vision base and the position of viewer are changed.