• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.4
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• pp.121-128
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• 2005

In most researches on the ride comfort analysis of passenger vehicles, the flexibility of the vehicle body has been not considered as an important factor, because the resonance frequencies of the vehicle body related to pitching, yawing and rolling motions are below 10Hz while the resonance frequencies of the vehicle body related to the flexibility are above 20Hz approximately. Nevertheless, the paper shows that the consideration of the local flexibility (or local stiffness) of the 4 corners on which shock absorbers are mounted influences the ride comfort. A simple beam model is devised to qualitatively examine the effect of the change of the local stiffness of the vehicle body on the ride comfort. Based on the results obtained from the analysis of the one-dimensional model, multi-body dynamic analysis considering the flexibility of the vehicle body is performed using ADAMS and MSC/NASTRAN. Natural frequencies and mode shapes computed by MSC/NASTRAN are used as input data for multi-body dynamic analysis in ADAMS. Through simulations using ADAMS, it has been found that the ride comfort can be improved by changing the local stiffness of the vehicle body and that the simulation results agree with experiment results.

• Journal of the Korea Convergence Society
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• v.10 no.7
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• pp.261-266
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• 2019

The purpose of this study was to investigate the effects of coordinative locomotor training wit on balance and flexibility of elementary school baseball players. A sample of 30 subjects were recruited for this study. Coordinative locomotor training group(n=15) with elastic band and coordinative locomotor training group(n=15) were six times a week for four. For evaluation of balance, Biorescue was used and for evaluation of sit-and-reach. The results were as follows: there were significant differences in balance and flexibility accoording to time. From the results, elastic band in coordinative locomotor training is expected to be an effective intervention for elementary school baseball players.

• Journal of Gifted/Talented Education
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• v.22 no.2
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• pp.467-482
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• 2012

In this research, the TRIZ program was developed for the growth of creativity of elementary school students. As for the TRIZ program that was developed in this research, it reconfigured the 40 of principles of the TRIZ within current curriculum, so that it would be possible for all elementary school students to receive their education in school for the growth of creativity. In order to adopt the 4-stages-class model that was developed, I made sample kit for utilizing TRIZ, and developed lesson plans along with materials 13-worksheet for lower-grade students, as well as lesson plans along with materials 12-worksheet, for higher-grade students. This program was applied to 2nd grade students of Y elementary school and 6th grade students of J elementary school, and according to the DESK theory, I subdivided the creativity into fluency, flexibility, originality, and exquisiteness, and it was shown that all of fluency, flexibility, originality, and exquisiteness were developed in elementary students who participated in TRIZ program compared with non-participated students. In conclusion, it was possible to understand that TRIZ program was effective for the growth of creativity of elementary school students.

• New & Renewable Energy
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• v.8 no.2
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• pp.33-43
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• 2012

Why solar companies preferred vertical integration of whole value chain? Major solar companies have built internally strong vertical integration of entire PV value chain. We raise a question whether such integration increases the corporate value and whether market situation affects the result. To test these questions, we conducted multi-variant analysis where characteristic factors mainly affect the corporate value measured in terms of Tobin'Q, based on the financial and non-financial data of PV companies listed in US stock market between 2005 and 2010. We hypothesize that since integration increases the overall efficiency but decreases the flexibility to adjust to various market situation, the combined effect of the efficiency gain and the flexibility loss ultimately determines the sign of integration effect on the corporate vale. We infer that the combined effect will be influenced heavily by business cycle, as in boom market (Seller's market) the efficiency gain may be larger than the flexibility loss and vice versa in bust market. We test whether the sign of combined effect changes after the year of 2009 and which factors influence most the sign. Year of 2009 is known as the year when market shifted from Seller's to Buyer's market. We show that 1) integration increases corporate value in general but after 2009 integration significantly decreases the value, 2) the ratios such as Production/Total Cost, Cash turnover period chosen for reversal of the flexibility measure are negatively affect Tobin's Q and especially stronger after 2009. This shows the flexibility improves corporate value and stronger in the recess period (Buyer's market). These results imply that solar company should set up integration strategy considering the tradeoff between efficiency and flexibility and the impact of the business cycle on both factors. Strategy only based on the price competitiveness determined in boom time can bring undesirable outcomes to the company. In addition, Strategic alliances in some value chains as a flexible bondage should be taken in account as complementary choice to the rigid integration.

• Computers and Concrete
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• v.25 no.3
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• pp.273-282
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• 2020

A new seismic design methodology for precast concrete diaphragms has been developed and incorporated into the current American seismic design code. This design methodology recognizes that diaphragm inertial forces during earthquakes are highly influenced by higher dynamic vibration modes and incorporates the higher mode effect into the diaphragm seismic design acceleration determination using a first mode reduced method, which applies the response modification coefficient only to the first mode response but keeps the higher mode response unreduced. However the first mode reduced method does not consider effects of diaphragm flexibility, which plays an important role on the diaphragm seismic response especially for the precast concrete diaphragm. Therefore this paper investigated the effect of diaphragm flexibility on the diaphragm seismic design acceleration for precast concrete shear wall structures through parametric studies. Several design parameters were considered including number of stories, diaphragm geometries and stiffness. It was found that the diaphragm flexibility can change the structural dynamic properties and amplify the diaphragm acceleration during earthquakes. Design equations for mode contribution factors considering the diaphragm flexibility were first established through modal analyses to modify the first mode reduced method in the current code. The modified first mode reduced method has then been verified through nonlinear time history analyses.

• Journal of the Korean Applied Science and Technology
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• v.19 no.3
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• pp.167-173
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• 2002

The isoflavone as a derivatives of flavone is colorless crystalline compounds. It acts on synthesis of fibronectine, collagen III, collagen I in human normal fibroblast by same biological activity to animal hormone. In this study, we tried to search and demonstrate system content rate of dermal translocation system for cosmetics using microemulsion containing isoflavone. The results of microemulsion stability test by centrifugation, storage in incubator and circulation chamber showed that separation of phase did not appear after 30 days. By the skin flexibility test, it has confirmed efficiency and effect as cosmetics materials. As the result, the microemulsion showed that skin flexibility factor improved up to 7.6%. We could confirm that O/W type microemulsion was stable system.

• Steel and Composite Structures
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• v.24 no.4
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• pp.425-439
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• 2017

As a thin-walled structure, local joint flexibility (LJF) in a tubular structure is prominent, and it may produce significant effect on the static performance for the overall structure. This study presents a simplified analytical model to analyze the static behavior for a steel tubular structure with LJF. The presented model simplifies a tubular structure into a frame model consisted of beam elements with considering the LJFs at the connections between any two elements. Theoretical equations of the simplified analytical model are deduced. Through comparison with 3-D finite element results of two typical planar tubular structures consisted of T- and Y-joints respectively, the presented method is proved to be accurate. Furthermore, the effect of LJF on the overall performance of the two tubular structures (including the deflection and the internal forces) is also investigated, and it is found from analyses of internal forces and deformation that a rigid connection assumption in a frame model by using beam elements in finite element analysis can provide unsafe and inaccurate estimation.

• Journal of the Korean Society of Physical Medicine
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• v.12 no.3
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• pp.23-32
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• 2017

PURPOSE: Flexibility and range of motion are very important factors in sports performance, rehabilitation, and musculoskeletal pain. The purpose of this study was to measure the effects of cupping therapy on flexibility, muscle activity, and pain threshold of hamstring muscle compared to passive stretching in healthy subjects. METHODS: Thirty healthy subjects were randomly assigned in a crossover design to cupping therapy and passive stretching. Subjects were tested to compare their effects according to the intervention such as Passive range of motion (PROM) (straight leg raising) and active range of motion (AROM). And algometer (pain) testing and MVC assessment using EMG were performed as dependent variables. RESULTS: The cupping therapy group and passive stretching group showed significant differences in all variables including PROM (p=.00, p=.00), AROM (p=.00, p=.03), Pain Threshold (p=.03, p=.08), Semitendinosus MVC (p=.01, p=.00), and Biceps femoris MVC (p=.01, p=.16). There were no significant differences between the two groups in all variables. CONCLUSION: These findings of this study suggested that cupping therapy has as much positive effect on flexibility, pain threshold, and muscle contraction as passive stretching. Also, it is more convenient and easier to work on patients than passive stretching. Therefore, cupping therapy should be considered as another option to treat range of motion, pain, and muscle activity in the clinical field.

• Journal of muscle and joint health
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• v.9 no.2
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• pp.177-186
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• 2002

The purpose of this study was examine the effect of self-exercise on patients with chronic arthritis. This study was performed from 1999 to 2001 with 107 subjects. Pain, Fatigue, Flexibility and Health status were measured. Data were analysed by SPSSWIN 10. 0 Package program, frequency, independent t-test and One Way ANOVA. The results were as follows : Of the 107 patients who were sutdied, mean age was 62 years and most of common disease were osteoarthritis. 67.4%was doing self-exercise and self-exercise consisted of 17 types of exercise. Fatigue was statistically different by disease type, duration of disease, education respectively. And fatigue, left shoulder flexibility were significantly different by duration of disease. There weren't significant differences between patient with self-exercise and patient without self-exercise on pain fatigue, flexibility and halth status. These findings confirms that self-exercise do not effective in increasing health improvement for the patients with osteoarthritis. From results of this study indicate that patients with arthritis should have taken systematic exercise such as the self-help education program aquatic exercise program for arthritis patient.

• Geomechanics and Engineering
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• v.24 no.4
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• pp.371-388
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• 2021

A novel flexibility-based beam-foundation model for inelastic analyses of beams resting on foundation is presented in this paper. To model the deformability of supporting foundation media, the Winkler-Pasternak foundation model is adopted. Following the derivation of basic equations of the problem (strong form), the flexibility-based finite beam-foundation element (weak form) is formulated within the framework of the matrix virtual force principle. Through equilibrated force shape functions, the internal force fields are related to the element force degrees of freedom. Tonti's diagrams are adopted to present both strong and weak forms of the problem. Three numerical simulations are employed to assess validity and to show effectiveness of the proposed flexibility-based beam-foundation model. The first two simulations focus on elastic beam-foundation systems while the last simulation emphasizes on an inelastic beam-foundation system. The influences of the adopted foundation model to represent the underlying foundation medium are also discussed.