• Journal of The Korean Association For Science Education
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• v.22 no.3
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• pp.560-570
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• 2002

This study was focused on whether secondary science teachers have consistent, integrative scheme on the definition of atmospheric pressure and phenomena caused by air pressure. We had made questionnaire and let 94 science teachers answer. We sorted the responses according to their major, school and compared them with the description in textbooks. The result can be summarized into three findings. First of all, teachers whose major is chemistry have strong tendency to understand that atmospheric pressure is caused by molecular motion though it, in textbooks, is defined as the pressure by weight of air mass. The half of respondents believed that decreasing of atmospheric pressure in high altitude is due to molecular motions, while most textbook says decrease in the weight of air mass. Secondly, many science textbooks show that air mass expands, rises, becomes less dense and the pressure of atmosphere becomes low when it receives heat. So, most of respondents explained low pressure is formed by lower density. Thirdly, they answered that they just teach the phenomena of air pressure by using the textbooks which mainly deal with the present state rather than a principle. In conclusion, the science textbooks should present the exact description and consolidated structures of those concepts to prevent students from having misconceptions on air pressure. In addition, training program for science teachers would be necessary to reconsider and explore the natural phenomena in various viewpoints.

• Journal of Acupuncture Research
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• v.35 no.3
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• pp.120-128
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• 2018

Background: Adhesive capsulitis (AC) is a common condition that includes shoulder pain and limited movement. Despite more than 100 years of AC treatment, the most efficacious treatment remains unclear. The aim of this study was to evaluate the feasibility of a randomized controlled trial (RCT) using acupuncture for AC. Methods: Thirty participants with AC were randomly assigned to acupuncture (A) or sham acupuncture (SA) groups. The participants received 15 acupuncture sessions over 6 weeks, and follow-up occurred for an additional 4 weeks thereafter. The primary clinical outcome was the numeric rating scale (NRS) for shoulder pain 6 weeks from the baseline. Secondary outcomes included range of motion (ROM) in the shoulder, the shoulder pain and disability index (SPADI), the EuroQol-5 dimensions (EQ-5D), the Pittsburgh sleep quality index (PSQI), and the patient global impression of change (PGIC). Results: Thirty participants were enrolled out of 37 screened individuals. Recruitment was conducted between August 2014 until May 2015. A total of 28 participants (93%) completed the 6-week intervention, and 26 participants (87%) completed the study. NRS, ROM, SPADI, EQ-5D, PSQI, and PGIC scores improved in both the experimental group and the sham group after 6 weeks, but the difference between the groups was not statistically significant. Adverse events were reported by 12 participants, although these events were not associated with acupuncture. Conclusion: A future RCT for AC may be feasible with some modifications to the recruitment plan and the secondary outcome measurement methods.

• Clinics in Shoulder and Elbow
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• v.11 no.1
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• pp.19-23
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• 2008

Purpose: To evaluate the bursoscopic findings of refractory primary adhesive capsulitis of the shoulder and to determine the clinical correlation. Materials and Methods: Arthroscopic capsular release was performed in 21 refractory adhesive capsulitis patients who had not responded to conservative treatment. The VAS for pain, range of motion, UCLA score was checked before and after surgery, and at the last follow up. Results: Bursitis, mild friction and impingement on coracoacromial ligament, as well as adhesion were observed. The function and pain improved earlier than after simple acromiohumeral joint capsular release. Conclusion: Subacromial bursoscopy helps rule out a hidden secondary frozen shoulder or secondary changes with primary adhesion. In addition, it has the advantage of being both a treatment and procedure for making a prognosis.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.7
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• pp.1675-1683
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• 1995

A numerical study of the fluid flow and heat transfer characteristics of the two-dimensional impingement jet with a confinement plate has been carried out. The fluid flow was calculated by solving the full Navier-Stokes equation. In doing that, the well known SIMPLER algorithm was used and the trouble making convection term was discretized according to QUICKER scheme. The energy equation was simply solved by using the SOR method. For the Reynolds number of 10000, two channel heights, say 1.5 and 3.0 times the jet exit width, and two thermal boundary conditions constant wall temperature and constant wall heat flux were considered. Discrete heat sources were flush mounted along the impingement plate at a distance of 0, 2, 3, 4, 5, 6, 10, 12, times the jet exit width from the stagnation point. The length of each heat source is 4 times the jet exit width long. The Nusselt number averaged over each heat source was compared with experiment. Comparison shows that both calculations and experiment have the secondary peak of Nusselt number at downstream of stagnation point, even though there is a little quantitative difference in between. The difference is believed due to abscure thermal boundary condition in experiment and also accuracy of turbulence model used. The secondary peak is shown to be caused by rigorous turbulent flow motion generated as the wall jet flow is retarded and developes into the channel flow without flow reversal.

• Structural Engineering and Mechanics
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• v.61 no.4
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• pp.497-510
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• 2017

A framed structure may be composed of two sub-structures, which are linked by a hinged joint. One sub-structure is the primary system and the other is the secondary system. The primary system, which is subjected to the periodic external load, can give rise to an auto-parametric resonance of the second system. Considering the geometric-stiffness effect produced by the axially internal force, the element equation of motion is derived by the extended Hamilton's principle. The element equations are then assembled into the global non-homogeneous Mathieu-Hill equations. The Newmark's method is introduced to solve the time-history responses of the non-homogeneous Mathieu-Hill equations. The energy-growth exponent/coefficient (EGE/EGC) and a finite-time Lyapunov exponent (FLE) are proposed for determining the auto-parametric instability boundaries of the structural system. The auto-parametric instabilities are numerically analyzed for the two frames. The influence of relative stiffness between the primary and secondary systems on the auto-parametric instability boundaries is investigated. A phenomenon of the "auto-parametric internal resonance" (the auto-parametric resonance of the second system induced by a normal resonance of the primary system) is predicted through the two numerical examples. The risk of auto-parametric internal resonance is emphasized. An auto-parametric resonance experiment of a ${\Gamma}$-shaped frame is conducted for verifying the theoretical predictions and present calculation method.

• Korean Journal of Applied Biomechanics
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• v.20 no.4
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• pp.447-455
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• 2010

The objective of this study was to analyze the difference in kinematic variables for successful and unsuccessful golf putting strokes. The study population included 8 male secondary school golf players who had played golf for over 3 years and whose handicap was 4 or lower. A hole was made on a 5-m-long artificial flat mat for practice, and an environment similar to that of a real green was created. The participants' motions were analyzed through 3D image analysis, and the difference in kinematic variables for successful and unsuccessful putting strokes in the same direction was determined. Data analysis revealed the following findings: The time spent for a segment of putting was the greatest for the backswing segment for both successful and unsuccessful strokes. During address and impact, the both changed to a larger extent. For successful putting strokes, the change in the elbow angle during the downswing was greater for the right elbow than for the left elbow. For both successful and unsuccessful putting strokes, the left shoulder angle increased during the segment from address to the turning point and decreased during the segment from the turning point to impact. In contrast, the right shoulder angle significantly differed between successful and unsuccessful putting strokes only during address. During successful and unsuccessful motions, the swing was executed with the moving displacement of the X-axis of the club head maintained almost constant along a straight light without back and forth movement. In the backswing segment, moving displacement of the Y- and Z-axes was greater in successful strokes than in unsuccessful strokes; however, this difference was very small for the Y-axis. The velocity of the club head for successful and unsuccessful motions significantly differed during address and at the turning point. The highest velocity of the ball was greater for successful than for unsuccessful putting strokes.

• Clinics in Shoulder and Elbow
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• v.25 no.1
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• pp.28-35
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• 2022

Background: Given the complications involved in corticosteroid (CS) injections, subacromial platelet-rich plasma (PRP) injections may provide a valid alternative to CS in the treatment of rotator cuff (RC) tendinopathy. Methods: We retrospectively reviewed a total of 98 patients affected by RC tendinopathy who were treated with either subacromial injection of PRP or CS. The PRP group received three injections of autologous PRP at 2 weeks interval, and the CS group received one injection of CS. The Western Ontario Rotator Cuff Index (WORC) was the primary outcome measure, while the secondary outcome measures were the visual analog scale (VAS), range of motion (ROM), and need for cuff repair surgery, which were analyzed at intervals of 6, 12, and 18 months. Results: A total of 75 patients were included in the analysis (PRP, n=35; CS, n=40). The mean follow-up for PRP was 21.1±8.7 months and for CS was 33.6±16.3 months (p<0.001). Both groups showed improvement in WORC, VAS, and ROM. No significant differences were detected between the two groups in any of the primary (WORC) or secondary outcomes over 6, 12, and 18 months (all p>0.05). No adverse events were detected. Conclusions: Both treatments improved patient symptoms, but neither resulted in a significantly better outcome in this series of patients. PRP can be a safe and feasible alternative to CS, even at long-term follow-up, to reduce local and systemic effects involved with CS injections.

• Smart Media Journal
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• v.13 no.2
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• pp.145-155
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• 2024

As the importance of software and artificial education is emphasized on the digital transformation era, various educational materials are being developed and distributed. To achieve the purpose of software education, various software education programs suitable for school settings need to be provided. In this paper, we developed a software education program using self-driving that can be applied to secondary school software education and applied it to secondary school students. The developed software education program is a physical computing program consisting of various motion control programs such as object detection, line tracing using various sensors, focusing on experience and practice. As a result of the survey, students' attitudes and career orientation toward software and artificial intelligence, and satisfaction with software education were over 90%, and satisfaction with the proposed program was over 95%.

• Journal of Korea Water Resources Association
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• v.52 no.10
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• pp.743-752
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• 2019

The flow in the meandering channel is characterized by the spiral motion of secondary currents that typically cause the erosion along the outer bank. Hydraulic structures, such as spur dike and groyne, are commonly installed on the channel bottom near the outer bank to mitigate the strength of secondary currents. This study is to investigate the effects of submerged vanes installed in a $90^{\circ}$ meandering channel on the development of secondary currents through three-dimensional numerical modeling using the hybrid RANS/LES method for turbulence and the volume of fluid method, based on OpenFOAM open source toolbox, for capturing the free surface at the Froude number of 0.43. We employ the second-order-accurate finite volume methods in the space and time for the numerical modeling and compare numerical results with experimental measurements for evaluating the numerical predictions. Numerical results show that the present simulations well reproduce the experimental measurements, in terms of the time-averaged streamwise velocity and secondary velocity vector fields in the bend with submerged vanes. The computed flow fields reveal that the streamwise velocity near the bed along the outer bank at the end section of bend dramatically decrease by one third of mean velocity after the installation of vanes, which support that submerged vanes mitigate the strength of primary secondary flow and are helpful for the channel stability along the outer bank. The flow between the top of vanes and the free surface accelerates and the maximum velocity of free surface flow near the flow impingement along the outer bank increases about 20% due to the installation of submerged vanes. Numerical solutions show the formations of the horseshoe vortices at the front of vanes and the lee wakes behind the vanes, which are responsible for strong local scour around vanes. Additional study on the shapes and arrangement of vanes is required for mitigate the local scour.

• Archives of Plastic Surgery
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• v.45 no.5
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• pp.458-465
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• 2018

Background Volar plate avulsion fracture of the proximal interphalangeal (PIP) joint is one of the most common hand injuries. In this study, we divided patients into two groups: patients with pure volar plate avulsion fracture, and patients with volar plate avulsion fracture concomitant with collateral ligament rupture. The purpose of this study was to compare long-term surgical outcomes between the two groups. As a secondary measure, the Mitek bone anchoring and polydioxanone (PDS) bone suturing techniques were compared. Methods A single-institutional retrospective review of the surgical treatment of volar plate avulsion fracture was performed. The cases were divided into those with pure volar plate avulsion fracture (group A, n=15) and those with volar plate avulsion fracture concomitant with collateral ligament rupture (group B, n=15). Both groups underwent volar plate reattachment using Mitek bone anchoring or PDS bone suturing followed by 2 weeks of immobilization in a dorsal protective splint. Results The average range of motion of the PIP joint and extension lag were significantly more favorable in group A (P<0.05). Differences in age; follow-up period; flexion function; visual analog scale scores; disabilities of the arm, shoulder, and hand scores; and the grip strength ratio between the two groups were non-significant. No significant differences were found in the surgical outcomes of Mitek bone anchoring and PDS bone suturing in group A. Conclusions Overall, the surgical outcomes of volar plate reattachment were successful irrespective of whether the collateral ligaments were torn. However, greater extension lag was observed in cases of collateral ligament injury.