• Title/Summary/Keyword: counterclockwise

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Analysis of refractive error according to the position of vision measurement using an automatic refractor (자동굴절검사기를 이용한 시력측정 자세에 따른 굴절이상도 분석)

  • Bong-Hwan, Kim;Sun-Hee, Han;Se-Hyeon, An;Chang-Seop, Sin;Won-Jeong, Jang;In-Seon, Hwang;Hyung-Soo, Kim
    • Journal of Korean Clinical Health Science
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    • v.10 no.2
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    • pp.1587-1593
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    • 2022
  • Purpose. This study was to investigate the degree of refractive error that occurs depending on the measurement location of the subject when performing a refraction test using the automatic refractor. Methods. When performing the auto-refraction test, measurements were taken while increasing the distance between the forehead and the forehead rest, and the measurements were made by tilting the head clockwise and counterclockwise. Results. During the auto-refraction test, significant refractive error occurred when the forehead was not attached to the forehead support or the subject's head was turned clockwise or counterclockwise. Conclusions. When performing a refraction test using an automatic refractor, the examiner will have to pay attention to whether the subject's forehead is in close contact with the forehead rest, and whether the head is tilted.

Analysis of Cis- Trans Photoisomerization Mechanism of Rhodopsin Based on the Tertiary Structure of Rhodopsin

  • Yamada, Atsushi;Yamato, Takahisa;Kakitani, Toshiaki;Yamamoto, Shigeyoshi
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.51-54
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    • 2002
  • We propose a novel mechanism (Twist Sharing Mechanism) for the cis-trans photoisomerization of rhodopsin, based on the molecular dynamics (MD) simulation study. New things devised in our simulations are (1) the adoption of Mt. Fuji potentials in the excited state for twisting of the three bonds C9=C10, C11=C12 and C13=14 which are modeled using the detailed ab initio quantum chemical calculations and (2) to use the rhodopsin structure which was resolved recently by the X-ray crystallographic study. As a result, we found the followings: Due to the intramolecular steric hindrance between 20-methyl and 10-H in the retinal chromophore, the C12-C13 and C10-C11 bonds are considerably twisted counterclockwise in rhodopsin, allowing only counterclockwise rotation of the C11 =C12 in the excited state. The movement of 19-methyl in rhodopsin is blocked by the surrounding three amino acids, Thr 118, Met 207 and Tyr 268, prohibiting the rotation of C9=C10. As a result only all-trans form of the chromophore is obtainable as a photoproduct. At the 90$^{\circ}$ twisting of C11=C12 in the course of photoisomerization, twisting energies of the other bonds amount to about 20 kcal/mol. If the transition state for the thermal isomerization is assumed to be similar to this structure, the activation energy for the thermal isomerization around C11=C12'in rhodopsin is elevated by about 20 kcal/mol and the thermal isomerization rate is decelerated by 10$\^$-14/ times than that of the retinal chromophore in solution, protecting photosignal from the thermal noise.

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The Influence of Nutrients Concentration and the Ratio on Phytoplankton Community Structure during Late Spring and Early Summer in Sagami Bay, Japan (춘계와 하계의 영양염 농도와 그 구성비가 식물플랑크톤의 군집구조에 미치는 영향평가)

  • Baek, Seung-Ho;Shimode, Shinji;Han, Myung-Soo;Kikuchi, Tomohiko
    • ALGAE
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    • v.23 no.4
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    • pp.277-288
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    • 2008
  • The relationship between nutrients and phytoplankton dynamics was investigated daily from 12 April to 22 July 2003 in Sagami Bay, Japan. According to multidimensional scaling (MDS) and cluster analysis, phytoplankton community was divided into four distinct groups. The first group was consisted of centric diatom species, such as Guinardia spp., Detonula spp., Letocylindrus danicus, Skeletonema costatum, Eucampia zodiacus and Chaetoceros spp.. The second and third clusters comprised mainly diatoms and dinoflagellates, respectively. The other cluster was restricted to the samples collected during the last sampling period when the rainfall and river discharge was frequently recorded. Canonical correspondence analysis (CCA) was applied to analyze four groups respectively, which focused on the effects of nutrients concentration and ratio on phytoplankton variations. Based on CCA analysis, most species of centric diatom were negatively correlated with DSi concentrations and Si/N ratio. Nutrients were strongly limited phytoplankton growth during the summer when the rainfall was not observed, whereas river discharge by rainfall and counterclockwise coastal currents (although the surface circulation pattern is often altered by Kuroshio Current, the counterclockwise coastal currents are generally dominant) has brought phytoplankton population accumulation and triggered the micoalgae growth in western part of the bay. Phosphorous (P) was strongly limited after significantly increases in the phytoplankton abundances. However, silicate (Si) was not a major limiting factor for phytoplankton production, since Si/DIN and Si/P ratio did not create any potential stoichiometric limitation. This indicates that high Si availability contributes favorably to the maintenance of diatom ecosystems in Sagami Bay.

Histological analysis on tissues around orthodontically intruded maxillary molars using temporary anchorage devices: A case report

  • Hui-Chen Tsai;Julia Yu-Fong Chang;Chia-Chun Tu;Chung-Chen Jane Yao
    • The korean journal of orthodontics
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    • v.53 no.2
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    • pp.125-136
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    • 2023
  • Before progress was recently made in the application of temporary anchorage devices (TADs) in bio-mechanical design, orthodontists were rarely able to intrude molars to reduce upper posterior dental height (UPDH). However, TADs are now widely used to intrude molars to flatten the occlusal plane or induce counterclockwise rotation of the mandible. Previous studies involving clinical or animal histological evaluation on changes in periodontal conditions after molar intrusion have been reported, however, studies involving human histology are scarce. This case was a Class I malocclusion with a high mandibular plane angle. Upper molar intrusion with TADs was performed to reduce UPDH, which led to counterclockwise rotation of the mandible. After 5 months of upper molar intrusion, shortened clinical crowns were noticed, which caused difficulties in oral hygiene and hindered orthodontic tooth movement. The mid-treatment cone-beam computed tomography revealed redundant bone physically interfering with buccal attachment and osseous resective surgeries were followed. During the surgeries, bilateral mini screws were removed and bulging alveolar bone and gingiva were harvested for biopsy. Histological examination revealed bacterial colonies at the bottom of the sulcus. Infiltration of chronic inflammatory cells underneath the non-keratinized sulcular epithelium was noted, with abundant capillaries being filled with red blood cells. Proximal alveolar bone facing the bottom of the gingival sulcus exhibited active bone remodeling and woven bone formation with plump osteocytes in the lacunae. On the other hand, buccal alveolar bone exhibited lamination, indicating slow bone turnover in the lateral region.

Net Radiation and Soil Heat Fluxes Measured on Coastal Wetland Covered with Reeds (갈대 서식 연안습지에서의 순복사와 토양열 플럭스)

  • Kim, Hee-Jong;Kim, Dong-Su;Yoon, Ill-Hee;Lee, Dong-In;Kwon, Byung-Hyuk
    • Journal of Environmental Science International
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    • v.16 no.2
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    • pp.233-239
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    • 2007
  • In the coastal wetland the mud is consist of fine particles, which means that it is characterized by small gap, and heat transfer is obstructed since moisture is found between the gaps. The relationship between net radiation ($R_N$) and soil heat flux($H_G$) shows a counterclockwise hysteresis cycle, which refer to a time lag behind in the maximal soil heat fluxes. The albedo is independent of seasonal variation of the vegetation canopy which plays very important roles to store and control the heat in the atmospheric surface layer.

Postural Stability and Balance Training Using Vision in Adult (정상성인의 자제 안정성과 시각을 이용한 균형훈련)

  • Kwon Mi-Ji
    • The Journal of Korean Physical Therapy
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    • v.10 no.1
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    • pp.149-154
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    • 1998
  • This study was designed 1) to quantitatively observe changes in static platform and 2) to observe balance performance using vision. Seventy-five subjects participated in the study. Subjects comprised 39 males and 36 females(mean ages=23.8 years) without neurologic and orthopaedic impairments. Static balance was measured with eyes open and closed. Subjects was required to move the cneter of balance curser in a counterclockwise for 30 sec. The effect for the COBx(-) suggests that subjects tended to maintain their weight slightly In the left. The time taken and the accuracy to move the center of balance from target to target was 14 sec, $49.47\%$. The body sway upon reaching the target was 7.3 AP sway and 11.88 LR sway distance. In this study, the data developed could be appropriate to use for sine comparisons when balance training patients with neurologic or orthopaedic impairments.

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Orthodontic Treatment of Inverted Maxillary Central Incisor with Labially Dilacerated Root : Case Report (순측 만곡치근을 갖는 역위 상악 중절치의 교정적 치험례)

  • Kim, Byeong-Cheon;Mun, Cheol-Hyeon
    • The Journal of the Korean dental association
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    • v.42 no.2 s.417
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    • pp.150-157
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    • 2004
  • Inverted maxillary incisor is that maxillary incisor rotates counterclockwise direction. The cause of this 'Inverted incisor' is the injury of the deciduous predecessor transmitted to the developing permanent tooth germ or displacement of permanent tooth crown portion from unknown origin. Dilaceration, defined as a distorted root from, may result from mechanical injury during eruption period or ectopic development of tooth germ. This article presents a case of an inverted and dilacerated maxillary right central incisor. Through orthodontic traction, the dilacerated and inverted incisor was successfully moved into the proper position.

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A Study on Ventilation Characteristics of Cargo-oil pump room (화물유 펌프실의 환기특성에 관한 연구)

  • 박찬수;조대환
    • Journal of Advanced Marine Engineering and Technology
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    • v.24 no.1
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    • pp.134-141
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    • 2000
  • In this study, a scaled model chamber was built to investigate ventilation characteristics of the Under floor Air-conditioning System. Experimental study was performed in model for cargo-oil pump room with inlet and outlet by visualization equipment with laser apparatus. Instant simultaneous velocity vectors at whole field were measured by 2-D PIV system(CACTUS'2000) which adopted two-frame grey-level cross correlation algorithm. The flow pattern reveals the large scale counterclockwise forced-vortex rotation from upside louver to lower scupper toward diagonal corner and also found small eddies at bottom layer

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A Study on the Reliability of a Dual Capacity Reciprocating Compressor (이중용량 왕복동 압축기 신뢰성 확보에 대한 연구)

  • Kim, Jong-Bong
    • Journal of the Korean Society for Precision Engineering
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    • v.26 no.7
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    • pp.81-90
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    • 2009
  • Due to environmental issues, the development of low energy consumption products has become one of the main topics in the home appliance industry. The energy consumption of a refrigerator depends on the efficiency of its compressor as well as on the refrigerator cycle design, such as the capacity modulation. In this study, a dual capacity, i.e., two-step capacity modulation (TCM), reciprocating compressor is developed. In a TCM compressor, capacity modulation is achieved by changing the dead volume in the cylinder. Instead of a concentric sleeve, an eccentric sleeve, a key, and a spring are used to change the dead volume for the clockwise and counterclockwise rotation of a motor. When the compressor changes its operating mode from full capacity to partial capacity or in opposite direction, the key may collide with the eccentric sleeve. The structural reliability and mode change reliability were confirmed by analysis and experiment.

Modeling of a Four-Quadrant Switched Reluctance Motor Drive on EMTDC/PSCAD

  • El-Samahy, Ismael;Marei, Mostafa I.;El-Saadany, Ehab F.
    • Journal of Electrical Engineering and Technology
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    • v.3 no.1
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    • pp.68-78
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    • 2008
  • This paper introduces a complete package for SRM drive on Power System Computer-Aided Design/Electromagnetic Transients (PSCAD/EMTDC). A three-phase SRM drive is modeled and simulated on PSCAD. The motor is modeled using an accurate nonlinear analytical model that takes into consideration the machine nonlinearities. A current control algorithm is applied for torque ripple minimization to achieve a smooth output torque which is necessary for high performance applications. The motor drive is tested for four-quadrant operations. The modeled SRM is capable of operating as a motor or generator during clockwise and counterclockwise motions. The proposed package helps in understanding the operational principles of switched reluctance motors, investigating the dynamic characteristics of SRM drives, and achieving a high performance dynamic control task.