• 제목/요약/키워드: Physical distance

검색결과 1,271건 처리시간 0.028초

Variation in the Main Kuroshio Path South of Japan

  • Sekine, Yoshihiko
    • Journal of the korean society of oceanography
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    • 제37권3호
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    • pp.196-200
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    • 2002
  • The time variation in the Kuroshio is studied by use of nine observed distances of the main Kuroshio axis from the Japanese coast. The observed distances over 1975 - 1995 are estimated from the Prompt Report of Oceanographic Conditions published by Hydrographic Department of the Maritime Safety Agency of Japan. It is shown that large sea level difference between Naze and Nishinoomote, which represents the volume transport of the southern inflow south of Kyushu, coincides with larger distance of the Kuroshio in the upstream area from off Kyushu to off eastern Kii Peninsula and smaller distance in the downstream area from off Omae-zaki to off Boso Peninsula. In contrast, large sea level difference between Nishinoomote and Aburatsu, which represents the volume transport of northern inflow south of Kyushu, corresponds to smaller distance in the upstream area and larger distance in the downstream area. Path dynamics of the Kuroshio is discussed with reference to the variation in Volume transport south of Kyushu.

비매개변수법에 의한 주파수별 스펙트럼감쇠 평가 (Nonparametric Ground-Motion Evaluation of Shear-Wave Fourier Spectra)

  • 연관희;박동희;장천중
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 2003년도 추계 학술발표회논문집
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    • pp.20-27
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    • 2003
  • The nonparametric method was employed to obtain detailed broadband attenuation characteristics of horizontal Fourier spectra without generally assigned constraint that derived path terms be zeros at a reference distance. Instead, path terms fer a reference distance were obtained based on the physical phenomenon that the seismic phase is stable over the hypocentral distance range from 200km to 400km so that the Q-values evaluated at several distances inside that region should be the same. The inverted path terms show three distinct linear regions roughly divided by hypocentral distances at 65km and 115km. Also complex behavior at the near distance range below 100km was revealed which can not be properly fitted by combination of single $Q_{0}$ $f^{η}$ model and any geometrical spreading models.s.

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Low-energy band structure very sensitive to the interlayer distance in Bernal-stacked tetralayer graphene

  • Lee, Kyu Won;Lee, Cheol Eui
    • Current Applied Physics
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    • 제18권11호
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    • pp.1393-1398
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    • 2018
  • We have investigated Bernal-stacked tetralayer graphene as a function of interlayer distance and perpendicular electric field by using density functional theory calculations. The low-energy band structure was found to be very sensitive to the interlayer distance, undergoing a metal-insulator transition. It can be attributed to the nearest-layer coupling that is more sensitive to the interlayer distance than are the next-nearest-layer couplings. Under a perpendicular electric field above a critical field, six electric-field-induced Dirac cones with mass gaps predicted in tight-binding models were confirmed, however, our density functional theory calculations demonstrate a phase transition to a quantum valley Hall insulator, contrasting to the tight-binding model prediction of an ordinary insulator.

Comparison of Surface Microhardness of the Flowable Bulk-Fill Resin and the Packable Bulk-Fill Resin according to Light Curing Time and Distance

  • Hyung-Min Kim;Moon-Jin Jeong;Hee-Jung Lim;Do-Seon Lim
    • 치위생과학회지
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    • 제23권2호
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    • pp.123-131
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    • 2023
  • Background: As a restorative material used to treat dental caries, the light-curing type resin is widely used, but it has the disadvantage of polymerization shrinkage. The Bulk-Fill composite resin was developed to solve these shortcomings, but the existing research mainly focused on comparing the physical properties of a composite resin and a Bulk-Fill resin. A study on the light curing time and distance of the Bulk-Fill resin itself tend to be lacking. Methods: This study compares the surface microhardness of specimens prepared by varying the light curing time and distance of smart dentin replacement (SDR) as a flowable Bulk-Fill resin and Tetric N-ceram as a packable Bulk-Fill resin, and confirms the polymerization time and distance that becomes the optimum hardness. To determine the hardness of the specimen, it was measured using the Vickers Hardness Number (Matsuzawa MMT-X, Japan). Results: In SDR, the surface microhardness decreased as the distance increased in all time groups in the change distance from the curing tip. In the change of light curing time with respect to the distance from curing tip, the surface microhardness increased as the time increased. In Tetric N-ceram, the surface microharness showed no significant difference in the change of the distance of curing tip in the group of 20 and 60 second. But in the group of 10 and 40 seconds, decreased as the distance increased. The surface microharness increased as the light curing time increased in all distance groups. Conclusion: When using SDR and Tetric N-ceram in clinical practice, it is considered that as the distance from the polymerization reactor tip increases, a longer light curing time than the polymerization time recommended by the manufacturer is required.

버스계단 내리기 시 구두 힐 높이와 착지거리에 따른 지면반력 파라미터 조사 (Investigation of the Ground Reaction Force Parameters According to the Shoe's heel Heights and Landing Distance during Downward Stairs on Bus)

  • 현승현;류재청
    • 한국운동역학회지
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    • 제24권2호
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    • pp.151-160
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    • 2014
  • The purpose of this study was to investigate the GRF(ground reaction force) parameters according to the shoes's heel heights and ground landing distances during downward stairs on bus. Participants selected as subject were consisted of young and healthy women(n=9, mean age: $21.30{\pm}0.48$ yrs, mean height: $164.00{\pm}3.05cm$, mean body mass: $55.04{\pm}4.41kg$, mean BMI: $20.47{\pm}1.76kg/m^2$, mean foot length: $238.00{\pm}5.37mm$). They were divided into 2-types of shoe's heel heights(0 cm/bare foot, 9 cm) and also were divides into downward stairs with 3 types of landing distance(20 cm, 35 cm, 50 cm). A one force-plate was used to collect the GRF(AMTI, USA) data from the sampling rate of 1000 Hz. The GRF parameters analyzed were consisted of the medial-lateral GRF, anterior-posterior GRF, vertical GRF, loading rate, Center of Pressure(${\Delta}COPx$, ${\Delta}COPy$, COP area) and Dynamic Postural Stability Index(MLSI, APSI, VSI, DPSI) during downward stairs on bus. Medial-lateral GRF and vertical GRF didn't show significant differences statistically according to the shoe's heel heights and landing distance, but 9 cm shoes heel showed higher vertical GRF than that of 0 cm bare foot in landing distance of 50 cm. Also anterior-posterior GRF didn't show significant difference statistically according to the shoe's heel heights, but landing distance of 20 cm showed higher than that of landing distances of 35 cm and 50 cm in anterior-posterior GRF. Loading rate didn't show significant difference statistically according to the landing distance, but 9 cm shoe's heel showed higher than that of 0 cm bare foot during downward stairs. The ${\Delta}COPy$ and COP area didn't show significant differences statistically according to the shoe's heel heights and landing distance, but 0 cm bare foot showed higher than that of 9 cm shoe's heel in ${\Delta}COPx$. Dynamic Postural Stability Index(MLSI, APSI, VSI, DPSI) didn't show significant differences statistically according to the landing distance, but 9 cm shoe's heel showed decreased value than that of 0 cm bare foot in dynamics balance. Considering the above, parameters of GRF showed different characteristics according to the shoe's heel heights and ground landing distances during downward stairs on bus.

The Effects of Virtual Reality Games in Posture Correction Exercise on the Posture and Balance of Patients with Forward Head Posture

  • Son, Ho-Hee
    • 대한물리의학회지
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    • 제15권2호
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    • pp.11-21
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    • 2020
  • PURPOSE: This study examined the effects of posture improvement exercise using virtual reality programs on the posture and balance of patients with forward head postures. METHODS: Thirty men and women in their 20 s, who had a forward head posture, were divided randomly into a group with posture correction exercise and a group with posture correction exercise combined with virtual reality programs. The posture correction exercise was composed of squats, XCO training, and chin-tuck exercise. In contrast, exercise with virtual reality games involved the Hot Squat, Climbey, and Baskhead programs while wearing a headset. Both groups performed the exercises 15 min a day, three times per week, for four weeks. The balance ability, distance between the acromion and earlobe, and neck joint range of motion were assessed before and after the exercises. RESULTS: Both groups showed significant reductions in the distance between the acromion and the earlobe, along with significant improvements in the range of joint motion. The group that performed the virtual reality exercises showed a significant increase in the limit of stability. Both groups showed a significant decrease in the sway length. In contrast, the group given the virtual reality exercises showed a significant reduction in the sway speed while standing with their eyes closed. CONCLUSION: Exercise applying virtual reality programs can be used in clinical and home programs to correct the postures of individuals with a forward head posture because they can trigger interest in inducing active participation.

The Circadian Effects on Postural Stability in Young Adults

  • Son, Sung Min
    • The Journal of Korean Physical Therapy
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    • 제29권3호
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    • pp.142-144
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    • 2017
  • Purpose: Few studies have addressed the effect of diurnal circadian rhythms on postural stability, and thus the aim of the present study was to examine circadian effects on static and dynamic postural stability in young adults. Methods: Twenty-four subjects (9 men, 11 women: age=$22.20{\pm}1.77$, height=$167.20{\pm}10.47$, weight=$59.85{\pm}10.66$) from a university community volunteered for this study. Static and dynamic balance testing, which recorded using a Good Balance system (Good Balance, Metitur Ltd, Finland) was conducted at 9:00, 13:00, and 17:00 hours on two consecutive days, and the sequencing of static and dynamic balance tests were randomized. Results were analyzed using the non-parametric one-way repeated Friedman test in SPSS version 18.0 (SPSS Inc., Chicago, IL, USA), and variable found to be significant were subjected to Wilcoxon post hoc testing. Results: Static and dynamic balance showed significant difference at the three times assessments (test at 9:00, 13:00, and 17:00) during circadian. In the post hoc test of static (anteroposterior distance, mediolateral distance and COP (center of pressure) velocity) and dynamic balance (performance time), 13:00 was the longer and faster than 9:00. Conclusion: These results indicated that control of postural balance is influenced by diurnal circadian rhythms, and confirm that control of postural balance is more effective and better performance in the 09:00 hours than 13:00 hours or 17:00 hours.

척주세움근의 키네시오 테이핑이 허리가동범위와 허리통증에 미치는 영향 (Effect of the Lumbar Range of Motion and Back Pain on Kinesiotaping of Erector Spinae Muscle)

  • 박종항;김윤환;이재준
    • 대한통합의학회지
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    • 제3권4호
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    • pp.53-59
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    • 2015
  • Purpose : To retestify about the changes of the range of motion and pain from kinesiotaping the erector spinae muscle. Method : Targeted the number of 30 people with low back pain and measured lumbar range of motion and pain before kinesiotaping on the erector spinae muscle. After that, the measured value were compared and analyzed. Result : First, before and after kinesiotaping, doing skin distraction test, the changes of the skin distance within each experiment group all statistically showed meaningful differences(p<0.05). Secondly, before and after kinesiotaping and testing pain threshold, it statistically showed meaningful differences(p<0.05). Conclusion : Both two groups showed that the change of the skin distance increased and the pain averagely decreased than before taping. Therefore, kinesiotaping is considered that it affected the low back, the range of motion and pain.

중학교 과학실험실 크기 결정에 관한 연구 (A study on the size of science laboratory of middle school)

  • 김대식;연제근
    • 한국과학교육학회지
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    • 제9권2호
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    • pp.47-53
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    • 1989
  • The standard of chair and desk is decided to design a science laboratory which would help students giving the chance to show their ability and participating spontaneously. The standard is come by the middle school students physical size of the 1986 national physical standard and they are classified into large, medium and small size. The size of laboratory is determined by the size of desk. the distance between desks and the number of students accommodated. By the middle school students physical standard, the heights of chair are 32, 34, 37cm and the widths of chair are 35, 37, 40cm. The desks heights are 53, 58, 63cm and the size is $110{\times}160cm$. The distance between rear and front of desk is 120cm and the left and right side of desk is 150cm. When 24, 36, 60 students are accommodated in laboratory, the size of laboratories are $9.6{\times}10.5m$, $12.7{\times}10.5m$ and $18.8{\times}10.5m$ respectively.

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새로운 팔걸이(MTBSDS)가 편마비환자의 견관절 아탈구에 미치는 효과 (The Study of a Newly Designed Sling(MTBSDS) for Hemiplegic Shoulder Subluxation)

  • 임호용;송태호;양대중;박승규
    • 대한임상전기생리학회지
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    • 제2권1호
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    • pp.71-82
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    • 2004
  • To compare the effectiveness of the hemisling, bobath sling, extension-type sling, and the newly designed Modified Triangular Bobath Sling with Distal Support on a hemiplegic shoulder subluxation. Fourteen hemiplegic patients with shoulder subluxation were evaluated by a simple X-ray with and without the slings and the vertical and horizontal distances on the plain AP views were measurement. The newly designed arm sling was compared in terms of the effects of correction with distal support attached with shoulder saddle sling. The arm sling designed for this study was developed for the purpose of maintaining patients hands in a functional position and performing ROM exercise of the shoulder easily, and prevention or correction to shoulder subluxation. The mean values of the vertical and horizontal distance were compared to determine if there was significant difference of function between the new sling and the conventional slings. The new sling provided the patients with good vertical correction of the subluxation(p<0.05) but did not increase the horizontal distance significantly. These results support the effectiveness of a new sling to decrease subluxation in hemiplegia. Further study on the long term effects or complication of the new sling is recommended.

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