• Title/Summary/Keyword: static studies

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Comparison of Static Balance Abilities on Respiratory Types in Healthy Adults (호흡 유형에 따른 건강한 성인의 정적균형능력 비교)

  • Yu, Daseul;Lim, Chaegil
    • Journal of The Korean Society of Integrative Medicine
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    • v.8 no.2
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    • pp.63-73
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    • 2020
  • Purpose: To investigate breathing-related changes in the balance ability of healthy adults. Methods: The participants were 36 healthy adults in their 20s and 30s. All participants were trained in three breathing (neutral, thoracic, and abdominal) methods one week before measurements. We used AccuSway to measure each participant's balance ability, using each breathing technique, in two postures (bipedal and unipedal). Results: During the bipedal balance task, abdominal breathing produced significant increases in path length and sway velocity. Abdominal breathing resulted in significant changes in sample entropy at the anteroposterior location compared with neutral breathing (p<.05). In the normalized anteroposterior location, there were significant changes in backward movement during thoracic and abdominal breathing compared with those during neutral breathing (p<.05). During the unipedal balance task, path length and sway velocity increased significantly during voluntary breathing compared with those during neutral breathing (p<.05). There was a significant change in backward movement when abdominal breathing-compared with neutral breathing-was used in the normalized anteroposterior location (p<.05). In the normalized left-right location, there was a significant shift to the right during thoracic breathing compared with that during neutral breathing (p<.05). Conclusion: Compared with neutral breathing, altered voluntary breathing patterns affect balance in healthy adults. Our results indicated that that static balance was more affected by abdominal breathing than by neutral breathing. Future studies should examine variables such as the breathing volume, rhythm, and method.

Structural Design and Analysis for High Altitude Long Endurance UAV (고고도 장기체공 무인기 구조 설계 및 해석)

  • Kim, Sung Joon;Lee, Seunggyu;Kim, Sung Chan;Kim, Tae-Uk;Kim, Seungho
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.22 no.3
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    • pp.68-73
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    • 2014
  • Research is being carried out at Korea Aerospace Research Institute with aim of design a HALE UAV(High Altitude Long Endurance Unmanned Air Vehicle). HALE UAVs are ideally suited to provide surveillance, remote sensing and communication relay capabilities for both military and civilian applications. HALE UAVs typically cruise at an altitude between 15 km and 20 km, travelling at low speed and circling specific area of interest. Airframe structural point of view, weight reduction of the airframe structure is the most important method to improve the flight efficiency. High modulus CFRP(Carbon Fiber Reinforced Polymer) has been used in designing the structure in order to minimize the airframe weight. With respect to structural design and analysis, the key question is to decide an adequate airworthiness certification base to define suitable load cases for sizing of various structural components. In this study, FAR(Federal Aviation Regulation) 23 have constituted the guidance and benchmark throughout all structural studies. And the MSC/FlightLoads was introduced to analyze the flight loads for the HALE UAV. The MSC/FlightLoads can compute the flexible air load and analyzed loads are distributed on structural model directly. A preliminary structural concept was defined in accordance with the estimated inertial and aerodynamic loads. A FEM analysis was carried out using the MSC/Nastran code to predict the static and dynamic behaviour of UAV structure.

A Review of Effects of Osteoarthritic Patient with a Varus Deformity of the Knee on Laterally Wedged Insole (외측 쐐기 깔창이 골관절염 환자의 내반슬에 미치는 영향에 관한 고찰)

  • Lee, Sang-Yong;Shin, Hyung-Soo;Bae, Sung-Soo
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.11 no.1
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    • pp.65-73
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    • 2005
  • Osteoarthritis has been considered a disease of the elderly because it is uncommon before the age of 40 years and is seen in approximately 80% of United States citizens older than 65 years. general population on kuri city in korea revealed that prevalence of knee osteoarthritis is 10.2%, increasing with age. High level of physical activity in men and age, post-menopause and obesity in women can be risk factor. Osteoarthritis is no evidence that a acquired process initiated much earlier in life through mechanical, metabolic, genetic, or other origins. A high tibial osteotomy alters static lower extremity alignment thereby decreasing medial compartment loading. As well, conservative treatment strategies, such as knee braces and valgus heel wedges, affect lover limb mechanics and attempt to reduce medial compartment loading. It was hypothesized that valgus heel wedges and modified orthoses would shift the center of pressure laterally on the foot during level walking, reducing the moment arm of the adduction moment in the frontal plane, thereby resulting in a decrease in the knee adduction moment. In the 1980s, the effect of wearing a laterally wedged insole on osteoarthritic patients with a varus deformity of the knee was firsted, and since then, kinematic and kinetic analyses concerning this condition have mainly focused on a static standing position. Since the early 1990s, the beneficial effect of wearing a laterally wedged insole to treat osteoarthritis of the knee has also been reported in dynamic conditions, but these studies did not answer the question of the kinematic and kinetic mechanisms that resulted in the reduced symptoms in patents with knee osteoarthritis. therefore, the effect of wearing laterally wedged insole has not been sufficiently studied.

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A Study on the Effective Use of Long-Baseline Kinematic Surveying by GPS (GPS에 의한 장기선 이동측량의 효율성 검토)

  • Kang, Joon-Mook;Lee, Young-Wook;Park, Joung-Hyun
    • Journal of Korean Society for Geospatial Information Science
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    • v.8 no.2 s.16
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    • pp.101-108
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    • 2000
  • Kinematic GPS surveying which can be obtained many three-dimensional topographical informations through a short-time measurement is being utilized mainly in the short base line of a few km and below The coordinate for the long base line depends on Static GPS surveying But it needs long time measurement. Therefore, the method which can decide a position of the long base line for a short time is being needed. To examine a possibility of an efficient use of kinematic GPS surveying of the long base line, this research has analysed an accuracy of the base line by static GPS surveying according to baseline distance, ephmeris, and observation time. As the results of research, I could see that accuracy was very low in case of the occurrence of cycle slip. When we use of precise ephmeris, we obtained 1ppm and less of accuracy with one-minute kinematic GPS surveying within 70km. If a lot of studies about the long baseline kinematic GPS surveying are processed, a topographical information necessary for each kind of construction field including land development could be utilized more efficiently.

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Incremental Processing Scheme for Graph Streams Considering Data Reuse (데이터 재사용을 고려한 그래프 스트림의 점진적 처리 기법)

  • Cho, Jungkweon;Han, Jinsu;Kim, Minsoo;Choi, Dojin;Bok, Kyoungsoo;Yoo, Jaesoo
    • The Journal of the Korea Contents Association
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    • v.18 no.1
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    • pp.465-475
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    • 2018
  • Recently, as the use of social media and IoT has increased, large graph streams has been generating and studies on real-time processing for them have been actively carrying out. In this paper we propose a incremental graph stream processing scheme that reuses previous result data when the graph changes continuously. We also propose a cost model to selectively perform incremental processing and static processing. The proposed cost model computes the predicted value of the detection cost and the processing cost of the recalculation area based on the actually processed history and performs the incremental processing when the incremental processing is more profit than the static processing. The proposed incremental processing increases the efficiency by processing only the part that changes when the graph update occurs. Also, by collecting only the previous result data of the changed part and performing the incremental processing, the disk I/O costs are reduced. It is shown through various performance evaluations that the proposed scheme outperforms the existing schemes.

2 Component Adhesive Leakage Repair Sealant Evaluation (2액형 점착 실링재의 누수보수재 평가에 관한 연구)

  • Cho, Il-Kyu;Kim, Keun-Hur;Oh, Sang-Keun
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.4 no.4
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    • pp.396-403
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    • 2016
  • This study is based on the evaluation of a single component injection type adhesive repair material and a new 2 component type used in leakage of underground concrete structures. The studies showed that based on different mix ratio of the 2 component type adhesive sealant comprised of an asphalt main and latex mixture agent the viscosity of the material compound differed significantly. Based on a permeability testing, injection and economic efficiency, and performance, the appropriate ratio was determined to be 6:1 and was proceeded to the KS F 4935 evaluation method. The 2 component type adhesive sealant uses a static mixer and a cartridge type container for the injection procedure and was able to satisfy the evaluation criteria outlined in the KS F 4935 standard.

Propose of Capacity Spectrum Method by Nonlinear Earthquake Response Analysis (질점계 비선형 지진응답해석에 의한 구조물의 역량스펙트럼 제안)

  • You, Jin-Sun;Yang, Won-Jik;Yi, Waon-Ho;Kim, Hyoung-Joon
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.27 no.6
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    • pp.501-508
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    • 2014
  • In this paper, a method on deducing the capacity spectrum based on nonlinear earthquake response analysis will be introduced. Damage assessment of general building draws the capacity spectrum through the Push-over analysis and the intersection point of capacity spectrum and demand spectrum is seen as performance point. Push-over analysis is the way to perform static analysis by using the equivalent static load changed from the effect of earthquake and predict the behavior of structures by earthquake. But, this method can not be taken into account in the effects of higher mode and the dynamic characteristic. Therefore, in order to calculate the capacity spectrum under dynamic properties of building. A capacity spectrum from going ahead with the nonlinear earthquake response analysis is suggested.

Wind pressure on a solar updraft tower in a simulated stationary thunderstorm downburst

  • Zhou, Xinping;Wang, Fang;Liu, Chi
    • Wind and Structures
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    • v.15 no.4
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    • pp.331-343
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    • 2012
  • Thunderstorm downbursts are responsible for numerous structural failures around the world. The wind characteristics in thunderstorm downbursts containing vortex rings differ with those in 'traditional' boundary layer winds (BLW). This paper initially performs an unsteady-state simulation of the flow structure in a downburst (modelled as a impinging jet with its diameter being $D_{jet}$) using a computational fluid dynamics (CFD) method, and then analyses the pressure distribution on a solar updraft tower (SUT) in the downburst. The pressure field shows agreement with other previous studies. An additional pair of low-pressure region and high-pressure region is observed due to a second vortex ring, besides a foregoing pair caused by a primary vortex ring. The evolutions of pressure coefficients at five orientations of two representative heights of the SUT in the downburst with time are investigated. Results show that pressure distribution changes over a wide range when the vortices are close to the SUT. Furthermore, the fluctuations of external static pressure distribution for the SUT case 1 (i.e., radial distance from a location to jet center x=$D_{jet}$) with height are more intense due to the down striking of the vortex flow compared to those for the SUT case 2 (x=$2D_{jet}$). The static wind loads at heights z/H higher than 0.3 will be negligible when the vortex ring is far away from the SUT. The inverted wind load cases will occur when vortex is passing through the SUT except on the side faces. This can induce complex dynamic response of the SUT.

Carbon-13 Nuclear Magnetic Resonance Spectroscopic Studies of $^{13}CO$ Adsorbed on Platinum Particles in L-Zeolites

  • 한옥희;Gustavo Larsen;Gary L. Haller;Kurt W. Zilm
    • Bulletin of the Korean Chemical Society
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    • v.19 no.9
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    • pp.934-942
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    • 1998
  • $^13CO$ chemisorbed on platinum particles in L-zeolite has been investigated by static and magic angle spinning NMR spectroscopy. The representative spectra are composed of a broad asymmetric peak with a center of gravity at 230±30 ppm and a sharp symmetric peak at 124±2 ppm which is tentatively assigned to physisorbed $CO_2$, on inner walls of L-zeolite. Overall, the broad resonance component is similar to our previous results of highly dispersed (80-96%) CO/Pt/silica or CO/Pt/alumina samples, still showing metallic characters. The principal difference is in the first moment value. The broad peak in the spectra is assigned to CO linearly bound to Pt particles in the L-zeolites, and indicates a distribution of isotropic shifts from bonding site to bonding site. The NMR results reported here manifest that the Pt particles inside of the L-zeolites channels are not collectively the same with the ones supported on silica or alumina with similar dispersion in terms of Pt particle shape and/or ordering of Pt atoms in a particle. As a result, Pt particles of CO/Pt/L-zeolite were agglomerated accompanying CO desorption upon annealing. There were no definite changes in the NMR spectra due to differences of exchanged cations. Comparison of our observation on CO/Pt/L-zeolite with Sharma et al.'s reveals that even when the first moment, the linewidtb, and the relaxation times of the static spectra and the dispersion measured by chemisorption are similar, the properties of Pt particles can be dramatically different. Therefore, it is essential to take advantage of the strengths of several techniques together in order to interpret data reliably, especially for the highly dispersed samples.

Effects of Whole Body Tilt Exercise with Visual Feedback on Trunk Control, Strength, and Balance in Patients with Acute Stroke: a Randomized Controlled Pilot Study (시각적 피드백을 이용한 전신 기울기 운동이 급성기 뇌졸중 환자의 체간 조절, 근력 및 균형에 미치는 효과: 무작위 대조군 예비연구)

  • Jung, Kyeoung-Man
    • Journal of the Korean Society of Physical Medicine
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    • v.13 no.4
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    • pp.75-84
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    • 2018
  • PURPOSE: This study was conducted to determine the effects of whole-body tilt exercise with visual feedback on trunk control, strength, and balance in patients with acute stroke. METHODS: The study included 18 patients with acute stroke who were randomly allocated to a Whole Body Tilt Exercise Group (WBTEG, N=9) and a General Trunk Exercise Group (GTEG, N=9). The WBTEG conducted whole-body tilt exercises with visual feedback, and the GTEG performed general trunk exercises. Both groups performed the exercises five times a week for 4 weeks. Outcomes were assessed using the trunk impairment scale (TIS), the trunk flexor and extensor strength test, the static balance test, and the Brunel Balance Assessment. RESULTS: After 4 weeks of intervention, both groups showed significantly improved TIS scores, muscle strength, and balance components (p<.05 in both groups). However, the improvement in TIS, muscle strength, and static balance in the WBTEG was significantly better than that in the GTEG (p<.05). CONCLUSION: Although both groups in this study showed post-intervention improvement, patients from the WBTEG who received visual feedback demonstrated more improvement. These findings indicate that whole-body tilt exercise with visual feedback may be effective at improving trunk control, trunk muscle strength, and balance in patients with acute stroke. Further studies are needed to gain a better understanding of the effectiveness of whole-body tilt exercise in patients with acute stroke.