• Structural Engineering and Mechanics
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• v.64 no.2
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• pp.225-232
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• 2017

Leaning-type arch bridge is a new spatial structural system composed of two vertical arches and two leaning arches. So far there has been no contrast analysis of leaning type arch bridge with different systems. This paper focus on a parametric study of leaning type arch bridge with different systems to find the influential rules on structural forces and stability and to provide some reference for practical designs. The parametric analysis is conducted with different rise-to-span ratios and bending rigidities of arch ribs by comparing internal forces. The internal forces decline obviously with the increase of the rise-to-span ratio. The bending moments at the centers of the main arches and the leaning arches are sensitive to the bending rigidities of arch ribs. Parametric studies are also carried out with different structural systems and leaning angles of the leaning arch by comparing the static stability. The lateral stiffness of leaning-type arch bridge is less than the in-plan stiffness. Compared with the leaning-type arch bridge without thrust, the leaning-type arch bridge with thrust has a lower stability safety coefficient. The stability safety coefficient rises gradually with the increase of inclining angle of the leaning arch. This study shows that the rise-to-span ratio, bending rigidities of arch ribs, structural system and leaning angles of the leaning arch are all critical design parameters. Therefore, these parameters in unreasonable range should be avoided.

• Architectural research
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• v.3 no.1
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• pp.45-52
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• 2001

In this paper, a pressurized single vertical arch and a pressurized leaning arch composed of flexible fabric material are considered. These arches have also been considered as a possible support structure for the tent-like structures. Two different boundary conditions are considered in leaning arches with fixed bases and pinned bases. The behaviors of the leaning arches are investigated for two tilt angles as 15, 30. For each angle, two loading conditions are considered as uniformly distributed load and wind loads. The F.E.M. is used through the all analysis procedures. For the results, load-deflection relationships, buckling modes, differences between two boundary conditions and deformed configurations are discussed.

• Journal of International Academy of Physical Therapy Research
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• v.11 no.4
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• pp.2229-2236
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• 2020

Background: Few comparative studies have been conducted on strengthening the anterior and posterior muscles of the trunk via lumbar stabilization exercises. Objectives: To compare the effects of forward leaning exercise and supine bridging exercise in stability exercise. Design: Randomized controlled clinical trial (single blind). Methods: Thirty subjects with spondylolisthesis were participated in this study. Fifteen subjects performed the bridging exercises and fifteen subjects performed the forward leaning exercises. Each exercise was held for ten seconds per repetition, and four repetitions were considered one sub-session. A total of four sub-sessions were performed in one full exercise session. The full exercise session required thirty minutes, including rest time. Trunk strength and range of motion and Oswestry disability index were measured. Results: Two weeks later, trunk flexion strength and trunk extension range of motion were significantly increased in the forward leaning exercise group than in the supine bridging group, trunk extension strength were significantly increased in the supine bridging exercise group than in the forward leaning group. After two weeks, the pain score was significantly lower in the forward leaning exercise group than in the supine bridging group. Conclusion: This study has shown that stabilization exercises are effective in increasing range of motion and strength in spondylolisthesis subjects. It was especially confirmed that the method of strengthening the anterior muscles of the trunk is more effective than the standard stabilization exercise method.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.413-414
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• 2008

Abstract should be in English. The leaning angle optimization of turbine blade using the genetic algorithm was conducted in this paper. The calculation CFD technique was based upon the Diagonalized Alternating Directional Implicit scheme(DADI) with algebraic turbulencemodeling. The leaning angle of VKI turbine blade was represented using B-spline curve. The control points are the design variable. Genetic algorithm was taken into account as an optimization tool. The objective was to minimize the total pressure loss. The optimized final geometry shows the better aerodynamic performance compared with the initial turbine blade.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.192-193
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• 2013

The purpose of this research is to comprehend experimentally the nature of human static load to wall for making use of the result as basic data to evaluate resisting force of lightweight wall. Human motions exerting static load are classified to 4 types, and two-hands pushing and shoulder pushing are defined as the instantaneously forcing motions with hands or shoulder put on the load plate, respectively. Back leaning and one-hand leaning are defined as motions of taking a rest in their respective comfortable posture. Measurement of static horizontal load caused by each motion showed that the highest load ratio depends on hardness of load plane and was 1.17~1.25 times of weight in two-hands pushing, 0.95~0.99 times in shoulder pushing, 0.16~0.18 times in back leaning, and 0.12~0.15 times in one-hand leaning.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.03a
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• pp.686-689
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• 2008

The leaning angle optimization of turbine blade using the genetic algorithm was conducted in this paper. The calculation CFD technique was based upon the Diagonalized Alternating Directional Implicit scheme(DADI) with algebraic turbulence modeling. The leaning angle of VKI turbine blade was represented using B-spline curve. The control points are the design variable. Genetic algorithm was taken into account as an optimization tool. The objective was to minimize the total pressure loss. The optimized final geometry shows the better aerodynamic performance compared with the initial turbine blade.

• Physical Therapy Korea
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• v.27 no.4
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• pp.264-271
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• 2020

Background: Because a forward-leaning posture can cause increased back muscle activity and pain. Therefore, an innovative method to reduce back muscle activity and pain is required. Objects: This study aimed to investigate the effects of a head support on muscle activity and pain in a forward-leaning posture. Methods: A total of 14 male and 16 female students (average age, 21.65 ± 2.37 years; height, 166.15 ± 7.90 cm; and weight, 60.65 ± 9.00 kg) were recruited for the experiment. Two of them were excluded due to musculoskeletal disorders. The muscle activity and pain in the forward-leaning posture were assessed while participants washed dishes for 7 minutes with and without a head support. The condition of using a head support was randomly performed with a 5-minutes break. To confirm a lumbar flexion angle of 30° during the experiment, myoVIDEO was used, and surface electromyography was used to measure muscle activity. Pain was assessed using a 10-point visual analog scale (VAS). The Wilcoxon signed-rank test was used to analyze the data, with p < 0.05 indicating statistical significance. Results: The cervical, thoracic, and lumbar erector spinae muscle activities significantly decreased with the use of the head support, but there was no significant change in the gluteus maximus. There was a significant decrease in the VAS score for the lumbar erector spinae (p < 0.05), but there was no significant change in the VAS score for the cervical region. Conclusion: The use of a head support in a forward-leaning posture reduced cervical, thoracic, and lumbar erector muscle activity and pain. Therefore, it could be recommended during working in a forward-leaning posture, such as during dishwashing, cooking, and working as a factory employee.

• Journal of the Korean earth science society
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• v.25 no.8
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• pp.739-747
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• 2004

This study was to promote meaning ways of leaning and observe the influence of concept maps on middle school students' conceptual formation with regards to the topic of the 'sea water'. Concept map is one way to examine a leaner's conceptual formation process. The subjects of this study consisted of four classes within the first grade students of a Busan middle school, which were divided into two groups: the experimental group which applied concept map teaching and the ordinary teaching group. This study was carried out before and after class, examining the science leaning achievement, self-directed leaning characteristics, and awareness change on the concept maps. The result of this study was as follows: First, the leaning achievement of middle school students was positively affected by the use of concept maps. Second, the teaching method with concept map was more effective self-directed leaning characteristics compared to the ordinary one. Third, concept map teaching was a positive reaction to conceptual formation.

• Journal of the Korean earth science society
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• v.25 no.8
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• pp.731-738
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• 2004

Secondary school science teachers' preception on inquiry learning was investigated by using questionnaires. According to these results, science teachers, who are participants of the current Korea National Science Curriculum, responded that raising the 'interest in science' was the most important objective of science education, and using practical scientific subject matters in class will do such. More than 72% of science teachers have used reconstructed materials. When reconstructed textbook contents were used, teachers through that the most important object is the 'acquirement of scientific knowledge'. Most science teachers perceived inquiry leaning as a student centered open investigation. Among factors that disturb inquiry leaning, critical ones were 'entrance examination', 'lake of teaching-leaning materials', 'little understanding of inquiry leaning', and 'lake of student's will to inquiry'.

• Journal of the Ergonomics Society of Korea
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• v.28 no.2
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• pp.35-55
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• 2009

The purpose of this study was to analyze the somatotypes of women in the early 20's, which were likely to deform due to bad posture in growth period. Accordingly, bodies of women aged 20 to 24, whose growth stopped, were measured directly and indirectly, and factors related to body shapes were extracted, body shapes were categorized based on the data, and the characteristics of each body shape were analyzed. As a result, 10 factors related to body shapes were extracted in the factor analysis, and body shapes were categorized into 6 types. Type 1 was the volume of body that was big and the longest; and the general frame was large. The straight body shape with small back protrusion; the shoulder is relatively thick and the width of the shoulder was normal. Type 2 was the volume of body that was the biggest and the upper body was the longest; the general frame was of average height. The forward body shape with the back flat; the shoulder was very thick, wide, and serious leaning forward. Type 3 was a body that was thin and the shortest. The sway-back body shape with big curvature at the back; the shoulder was thin, narrow, and straight. Type 4 was a body that was short stature, and the general frame was of average build. The forward body shape with the most serious back protrusion; the shoulder was normally thick, narrow, and straight. Type 5 was a group with small body, and the lower body and general frame are long. The sway-back body shape with protrusion at the upper shoulder and the sides leaning backward; the shoulder was thin, wide, and leaning forward. Type 6 was a thin and short body; and the general frame was small. The lean-back body shape with the smallest back protrusion and leaning backward; the shoulder was thin, narrow, and leaning backward. Characteristics of the classified body shapes can be used in producing ready-made clothes, and it is hoped that there will be follow-up studies on clothing pattern design and production based on this result.