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Acupuncture for Facet Joint Syndrome: A Review of Clinical Study (후관절 증후군의 침 치료에 대한 문헌 연구 보고)

  • Ji-Hyang Gu
    • Journal of Korean Medicine Rehabilitation
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    • v.33 no.1
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    • pp.13-29
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    • 2023
  • Objectives To evaluate the evidence supporting the effectiveness of acupuncture for facet joint syndrome. Methods We conducted search across 9 electronic databases (PubMed, EMBASE, Cochrane CENTRAL (CENTRAL), KoreaMed, Kmbase, Koreanstudies Information Service System (KISS), ScienceOn, China National Knowledge Infrastructure (CNKI), and Wanfang) to find clinical trials that used acupuncture as treatment for facet joint syndrome. The methodological quality of randomized controlled clinical trials (RCTs) were assessed using the Cochrane Risk of Bias (RoB) tool, while non-randomized controlled clinical trials (nRCTs) were assessed using the Cochrane Risk of Bias Assessment tool for Non-randomized Study (RoBANS) tool. Results Nine RCTs and one nRCT met our inclusion criteria. Fire needle was more effective than medial branch block in terms of visual analogue scale (VAS) after 1 month (p=0.02). Also, Fire needle was more effective than Ibuprofen in terms of VAS and oswestry disability index (ODI) (p<0.05). However, in the rest of the study results, the intervention group did not show a statistically significant difference than the control group. Conclusions Although our review found encouraging but limited evidence of acupuncture for facet joint syndrome, most of the studies included in the analysis were evaluated as methodologically high risk of bias. From now on further well-designed RCTs should be encouraged.

Experimental and numerical study of a steel plate-based damper for improving the behavior of concentrically braced frames

  • Denise-Penelope N. Kontoni;Ali Ghamari;Chanachai Thongchom
    • Steel and Composite Structures
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    • v.47 no.2
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    • pp.185-201
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    • 2023
  • Despite the high lateral stiffness and strength of the Concentrically Braced Frame (CBF), due to the buckling of its diagonal members, it is not a suitable system in high seismic regions. Among the offered methods to overcome the shortcoming, utilizing a metallic damper is considered as an appropriate idea to enhance the behavior of Concentrically Braced Frames (CBFs). Therefore, in this paper, an innovative steel damper is proposed, which is investigated experimentally and numerically. Moreover, a parametrical study was carried out to evaluate the effect of the mechanism (shear, shear-flexural, and flexural) considering buckling mode (elastic, inelastic, and plastic) on the behavior of the damper. Besides, the necessary formulas based on the parametrical study were presented to predict the behavior of the damper that they showed good agreement with finite element (FE) results. Both experimental and numerical results confirmed that dampers with the shear mechanism in all buckling modes have a better performance than other dampers. Accordingly, the FE results indicated that the shear damper has greater ultimate strength than the flexural damper by 32%, 31%, and 56%, respectively, for plates with elastic, inelastic, and plastic buckling modes. Also, the shear damper has a greater stiffness than the flexural damper by 43%, 26%, and 53%, respectively, for dampers with elastic, inelastic, and plastic buckling modes.

Numerical analysis of an innovative expanding pile under static and dynamic loading

  • Abdullah Cheraghi;Amir K. Ghorbani-Tanha
    • Geomechanics and Engineering
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    • v.32 no.4
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    • pp.453-462
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    • 2023
  • Designing pile foundations subjected to the uplift forces such as buildings, oil platforms, and anchors is becoming increasingly concerned. In this paper, the conceptual design of a new type of driven piles called expanding pile is presented and assessed. Some grooves have been created in the shaft of the novel pile, and some moveable arms have been designed at the pile tip. At first, static analyses using the finite element method were performed to evaluate the effectiveness of the innovative pile on the axial bearing capacity. Then its effect on seismic behavior of moment frame is considered. Results show that the expanding arms were provided an ideal anchorage system because of the soil's noticeable locking-up effect increasing uplift bearing capacity. For example at the end of the static tensile loading procedure, displacement decrement up to 55 percent is observed. In addition, comparing the uplift bearing capacity of the usual and new pile with different lengths in sand and clay layers shows noticeable effect and sharp increase up to about two times especially in longer piles. Besides, a sensible reduction in the seismic response and the stresses in the beam-column connection between 23-36 percent are achieved that ensures better seismic behavior of the structures.

A proposal for improving the behavior of CBF braces using an innovative flexural mechanism damper, an experimental and numerical study

  • Ghamari, Ali;Jeong, Seong‐Hoon
    • Steel and Composite Structures
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    • v.45 no.3
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    • pp.455-466
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    • 2022
  • Despite the considerable lateral stiffness and strength of the Concentrically Braced Frame (CBF), it suffers from low ductility and low seismic dissipating energy capacity. The buckling of the diagonal members of the CBF systems under cyclic loading ended up to the shortcoming against seismic loading. Comprehensive researches have been performing to achieve helpful approaches to prevent the buckling of the diagonal member. Among the recommended ideas, metallic damper revealed a better success than other ideas to enhance the behavior of CBFs. While metallic dampers improve the behavior of the CBF system, they increase constructional costs. Therefore, in this paper, a new steel damper with flexural mechanism is proposed, which is investigated experimentally and numerically. Also, a parametrical revision was carried out to evaluate the effect of thickness, slenderness ratio, angle of the main plate, and height of the main plates on the proposed damper. For the parametrical study, 45 finite element models were analyzed and considered. Experimental results, as well as the numerical results, indicated that the proposed damper enjoys a stable hysteresis loop without any degradation up to a high rotation equal to around 31% that is significantly considerable. Moreover, it showed a suitable performance in case of ductility and energy dissipating. Besides, the necessary formulas to design the damper, the required relations were proposed to design the elements outside the damper to ensure the damper acts as a ductile fuse.

Response modification and seismic design factors of RCS moment frames based on the FEMA P695 methodology

  • Mohammad H. Habashizadeh;Nima Talebian;Dane Miller;Martin Skitmore;Hassan Karampour
    • Steel and Composite Structures
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    • v.49 no.1
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    • pp.47-64
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    • 2023
  • Due to their efficient use of materials, hybrid reinforced concrete-steel (RCS) systems provide more practical and economic advantages than traditional steel and concrete moment frames. This study evaluated the seismic design factors and response modification factor 'R' of RCS composite moment frames composed of reinforced concrete (RC) columns and steel (S) beams. The current International Building Code (IBC) and ASCE/SEI 7-05 classify RCS systems as special moment frames and provide an R factor of 8 for these systems. In this study, seismic design parameters were initially quantified for this structural system using an R factor of 8 based on the global methodology provided in FEMA P695. For analyses, multi-story (3, 5, 10, and 15) and multi-span (3 and 5) archetypes were used to conduct nonlinear static pushover analysis and incremental dynamic analysis (IDA) under near-field and far-field ground motions. The analyses were performed using the OpenSees software. The procedure was reiterated with a larger R factor of 9. Results of the performance evaluation of the investigated archetypes demonstrated that an R factor of 9 achieved the safety margin against collapse outlined by FEMA P695 and can be used for the design of RCS systems.

Growth of Salix gracilistyla Miq. Originated from Provenance in Gangwon-do, Korea for Bioenergy Resource

  • Hyunseok Lee
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2020.12a
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    • pp.59-59
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    • 2020
  • Salix gracilistyla has a characteristic of fast growth especially in the river side or infertile soil, showing a lot of lateral branches and a strong root system among the Salix. spp. On the basis of results observed, we provide several growth characteristics of S. gracilistyla among some selected provenances. In two-year results, root collar diameter ranged from 33.5 mm to 56.7 mm. Taeback showed the lowest value, and Jeongseon and Hoengseong were higher than the other areas in the traits above. Height growth was the lowest in Samcheok and the highest in Wonju. To examine growth and development of lateral branches is important because S. gracilistyla has a lot of lateral branches which account for high biomass production. Length of lateral branch showed high variation, in which the highest number was observed in Yeongwol and the lowest in Samcheok. Many lateral branches were shown in Wonju. Preliminary study on biomass resources evaluation, we analyzed correlation between volume and length, and volume and root diameter. High correlation was observed between root diameter and plant volume. And we compared the observed volume with the caculated volume by regression formula. To evaluate Salix species as biomass resources, it is needed to survey growth characteristics continuously and adopt selection of individuals or families of high biomass and caloric values by reliable data. In addition, Salix spp. can be also applicable to selection breeding regime because of feasible propagation and fast growth.

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A Case Study of Educational Content using Arduino based on Augmented Reality

  • Soyoung Kim;Heesun Kim
    • International journal of advanced smart convergence
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    • v.12 no.4
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    • pp.268-276
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    • 2023
  • The representative branch of ICT education is Arduino. However, there are various problems when teaching using Arduino. Arduino requires a complex understanding of hardware and software, and this can be perceived as a difficult course, especially for beginners who are not familiar with programming or electronics. Additionally, the process of connecting the pins of the Arduino board and components must be accurate, and even small mistakes can lead to project failure, which can reduce the learner's concentration and interest in learning Arduino. Existing Arduino learning content consists of text and images in 2D format, which has limitations in increasing student understanding and immersion. Therefore, in this paper analyzes the necessary conditions for sprouting 'growing kidney beans' in the first semester of the fourth grade of elementary school, and builds an automated experimental environment using Arduino. Augmented reality of the pin connection process was designed and produced to solve the difficulties when building an automation system using Arduino. After 3D modeling Arduino and components using 3D Max, animation was set, and augmented reality (AR) content was produced using Unity to provide learners with more intuitive and immersive learning content when learning Arduino. Augmented reality (AR)-based Arduino learning content production is expected to increase educational effects by improving the understanding and immersion of classes in ICT education using Arduino and inducing fun and interest in physical computing coding education.

A DQN-based Two-Stage Scheduling Method for Real-Time Large-Scale EVs Charging Service

  • Tianyang Li;Yingnan Han;Xiaolong Li
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.18 no.3
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    • pp.551-569
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    • 2024
  • With the rapid development of electric vehicles (EVs) industry, EV charging service becomes more and more important. Especially, in the case of suddenly drop of air temperature or open holidays that large-scale EVs seeking for charging devices (CDs) in a short time. In such scenario, inefficient EV charging scheduling algorithm might lead to a bad service quality, for example, long queueing times for EVs and unreasonable idling time for charging devices. To deal with this issue, this paper propose a Deep-Q-Network (DQN) based two-stage scheduling method for the large-scale EVs charging service. Fine-grained states with two delicate neural networks are proposed to optimize the sequencing of EVs and charging station (CS) arrangement. Two efficient algorithms are presented to obtain the optimal EVs charging scheduling scheme for large-scale EVs charging demand. Three case studies show the superiority of our proposal, in terms of a high service quality (minimized average queuing time of EVs and maximized charging performance at both EV and CS sides) and achieve greater scheduling efficiency. The code and data are available at THE CODE AND DATA.

Out-of-phase and in-phase vibrations and energy absorption of coupled nanoplates on the basis of surface-higher order-viscoelastic-couple stress theories

  • Guangli Fan;Maryam Shokravi;Rasool Javani;Suxa Hou
    • Steel and Composite Structures
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    • v.50 no.4
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    • pp.403-418
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    • 2024
  • In this paper, vibration and energy absorption characteristics of a nanostructure which is composed of two embedded porous annular/circular nanoplates coupled by a viscoelastic substrate are investigated. The modified couple stress theory (MCST) and the Gurtin-Murdoch theory are applied to take into account the size and the surface effects, respectively. Furthermore, the structural damping effect is probed by the Kelvin-Voigt model and the mathematical model of the problem is developed by a new hyperbolic higher order shear deformation theory. The differential quadrature method (DQM) is employed to obtain the out-of-phase and in-phase frequencies of the structure in order to predict the dynamic response of it. The acquired results reveal that the vibration and energy absorption of the system depends on some factors such as porosity, surface stress effects, material length scale parameter, damping and spring constants of the viscoelastic foundation as well as geometrical parameters of annular/circular nanoplates. A bird's-eye view of the findings in the research paper offers a comprehensive understanding of the vibrational behavior and energy absorption capabilities of annular/circular porous nanoplates. The multidisciplinary approach and the inclusion of porosity make this study valuable for the development of innovative materials and applications in the field of nanoscience and engineering.

A novel aerodynamic vibration and fuzzy numerical analysis

  • Timothy Chen;Yahui Meng;Ruei-Yuan Wang;ZY Chen
    • Wind and Structures
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    • v.38 no.3
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    • pp.161-170
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    • 2024
  • In recent years, there have been an increasing number of experimental studies showing the need to include robustness criteria in the design process to develop complex active control designs for practical implementation. The paper investigates the crosswind aerodynamic parameters after the blocking phase of a two-dimensional square cross-section structure by measuring the response in wind tunnel tests under light wind flow conditions. To improve the accuracy of the results, the interpolation of the experimental curves in the time domain and the analytical responses were numerically optimized to finalize the results. Due to this combined effect, the three aerodynamic parameters decrease with increasing wind speed and asymptotically affect the upper branch constants. This means that the aerodynamic parameters along the density distribution are minimal. Taylor series are utilized to describe the fuzzy nonlinear plant and derive the stability analysis using polynomial function for analyzing the aerodynamic parameters and numerical simulations. Due to it will yield intricate terms to ensure stability criterion, therefore we aim to avoid kinds issues by proposing a polynomial homogeneous framework and utilizing Euler's functions for homogeneous systems. Finally, we solve the problem of stabilization under the consideration by SOS (sum of squares) and assign its fuzzy controller based on the feasibility of demonstration of a nonlinear system as an example.