• Computers and Concrete
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• v.28 no.6
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• pp.533-547
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• 2021

Calculating the shear capacity of slender reinforced concrete beams without shear reinforcement was the subject of numerous studies, where the eternal problem of developing a single relationship that will be able to predict the expected shear capacity is still present. Using experimental results to extrapolate formulae was so far the main approach for solving this problem, whereas in the last two decades different research studies attempted to use artificial intelligence algorithms and available data sets of experimentally tested beams to develop new models that would demonstrate improved prediction capabilities. Given the limited number of available experimental databases, these studies were numerically restrained, unable to holistically address this problem. In this manuscript, a new approach is proposed where a numerically generated database is used to train machine-learning algorithms and develop an improved model for predicting the shear capacity of slender concrete beams reinforced only with longitudinal rebars. Finally, the proposed predictive model was validated through the use of an available ACI database that was developed by using experimental results on physical reinforced concrete beam specimens without shear and compressive reinforcement. For the first time, a numerically generated database was used to train a model for computing the shear capacity of slender concrete beams without stirrups and was found to have improved predictive abilities compared to the corresponding ACI equations. According to the analysis performed in this research work, it is deemed necessary to further enrich the current numerically generated database with additional data to further improve the dataset used for training and extrapolation. Finally, future research work foresees the study of beams with stirrups and deep beams for the development of improved predictive models.

• The Journal of Korean Academy of Sensory Integration
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• v.9 no.2
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• pp.15-28
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• 2011

Objective : The purpose of the study was to investigate effects of sensory integration therapy on self-regulation capacities of children with cerebral palsy. Methods : Subjects of this study were four years old girl and six years old boy, living in P city. Both were diagnosed as diplegia. Research design used in this study is ABA' design for a single-subject research. The experimental period was 12 weeks with 22 sessions of treatment. It was divided into three phase: 6 sessions for baseline phase (A), 14 sessions for treatment phase (B), 2 sessions for baseline phase (A'). There was no treatment on the baseline phases, and sensory integration therapy focused vestibular and proprioceptive stimuli was conducted on the treatment phase. At each session, subjects' behaviors has been recorded with a Digital Camera for 10 minutes and then the occurrence frequency of problematic behavior was identified based on the operational definition of it. Results : In comparison with the baseline phase (A), the occurrence frequency was reduced during the treatment phase for three types of problematic behavior associated with the self-regulatory capacities. The tendency of reducement was maintained during baseline phase (A'). Conclusion : Based on the result, it was implied that sensory integration therapy has a positive effect on the self-regulation capacities in children with cerebral palsy.

• Journal of Forest and Environmental Science
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• v.13 no.1
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• pp.66-80
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• 1997

Pinus koraiensis is one of the major speciese which have been recently planted for ten years and consists of 31% of total plantation. Presently young stand less than 30 years consists of 87% of total forest, but tending thinning of it is hardly carried out and the desirable direction for the thinning is not established yet. The objective of the study is to introduce the optimum thinning plan and thinning method through the long-run experiment of tending thinning for the Pinus koraiensis stand. The experiments carry out to interprete its growth model on the subject of two thinning experimental plots and yield table of Pinus koraiensis. As the basic step for understanding the thinning process, a theoretical growth model which is suitable to express the growth process is required. For that purpose, three growth functions (Mitscherlich, 4 parameter Richards, 3 parameter Richards) are applied to the diameter growth of the sample trees which are taken in the two plots. The results show that 3 parameter Richards is the most suitable. It is also verified that the diameter growth, the height growth, and the decrease in the number of stocks can be estimated by this function. To estimate the growth change of single tree, growth model including parameter h which is related to the occupation area of single tree are introduced. The parameter h can be estimated by using the data of the diameter growth obtained from the established experimental plots. Therefore, if both verification and modification of the usefulness of the model suggested is made, equations which tell about the thinning effects could be drived by estimating the growth process of single tree in advance.

• Physical Therapy Korea
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• v.10 no.1
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• pp.129-137
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• 2003

A single subject experimental design (alternating treatment design) was used to compare the effects of only ultrasound and ultrasound combined with stretching of the joint capsule on the ROM increase and pain reduction in patients with frozen shoulder. Two subjects were included in each group. In the only ultrasound treatment sessions, ultrasound was applied at the pain point of the shoulder joint in supine position. In the ultrasound combined with stretching treatment sessions, ultrasound was applied at the pain point of the shoulder joint positioned in external rotation and abduction in sitting position. Only ultrasound treatment and ultrasound combined with stretching treatment were alternately performed on each patient. Pain and disability was measured by shoulder pain and disability index (SPADI), and range of motion (ROM) was measured by scratch test. The results of this study showed that ultrasound combined with stretching treatment were more effective than only ultrasound treatment in ROM increase and pain reduction. However, disability score was not significantly different.

• International Journal of Railway
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• v.5 no.2
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• pp.55-64
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• 2012

Subject of the paper is a particular configuration of overhead line, in which noise barrier structure is used as supports of the catenary instead of standard poles. This configuration is foreseen in case the noise barrier position is in conflict with the poles location. If the catenary is supported by the noise barrier, the motion that the latter undergo due to wave pressure associated to train transit is transmitted to the overhead line, so that potentially it influences the interaction between the catenary itself and the pantograph of the passing train. The paper focuses on the influence of such peculiar configuration on the quality of the current collection of high speed pantograph, for single and double current collection. The study has been carried out first with an experimental investigation on the pressure distribution on noise barrier, both in wind tunnel and with in-field tests. Subsequently a numerical analysis of the dynamics of the barrier subjected to the wave pressure due to train transit has been carried out, and the output of such analysis has been used as input data for the simulation of the pantograph-dynamic interaction at different speeds and with front or rear pantograph in operation. Consideration of structural modifications was then highlighted, in order to reduce the influence on the contact loss percentage.

• Nuclear Engineering and Technology
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• v.55 no.7
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• pp.2454-2465
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• 2023

Film boiling may lead to burnout of the heating element. Even though burnout does not occur, the heating element is subject to deformation because it is not sufficiently strong to withstand external loads. In particular, the ballooning and rupture of a tube under film boiling are important phenomena in the field of nuclear reactor safety. If the tube-type cladding of nuclear fuel ruptures owing to high internal pressure and thermal load, radioactive materials inside the cladding are released to the coolant. Therefore, predicting the ballooning and rupture is important. This study presents numerical simulations to predict the ballooning behavior and rupture time of a horizontal tube at high internal pressure under saturated film boiling. To do so, a multi-step coupled simulation of conjugated film boiling heat transfer and ballooning using creep model is adopted. The numerical methods and models are validated against experimental values. Two different nonuniform heat flux distributions and four different internal pressures are considered. The three-step simulation is enough to obtain a convergent result. However, the single-step simulation also successfully predicts the rupture time. This is because the film boiling heat transfer characteristics are slightly affected by the tube geometry related to creep ballooning.

• Journal of the Korean Society of Clothing and Textiles
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• v.47 no.6
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• pp.1204-1220
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• 2023

With the rising importance placed on sustainability for brands, a plethora of research addresses consumer responses concerning eco-friendly products. While positive effects of eco-friendly traits on beauty products have been discussed, this study addresses a wide research gap in the makeup category. Based on the goal-attribute theory and the lay theory of ethicality, detrimental effects of eco-friendly ingredient claims on perceived appearance enhancement attributes (AEA) were examined. A between-subject, single-factor (eco-friendly ingredient claims present vs. absent) web-based experimental design tested the effect of conditions on makeup products that emphasized AEA. Results found a negative effect of eco-friendly ingredient claims on perceived AEA, supporting previous literature regarding the 'green gap'. Evidence showed that perceived AEA fully mediated the effect of eco-friendly claims on purchase intention, which was moderated by AEA preference. Interestingly, findings show that the purchase intention of respondents with a near-average preference for AEA was not moderated. Results contribute to preexisting literature by extending the lay theory of ethicality and product function mismatch to the field of makeup. Managerial implications are discussed, including opportunities for eco-friendly makeup products to appeal to alternative benefits.

• Journal of Pharmacopuncture
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• v.19 no.4
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• pp.350-358
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• 2016

Objectives: This study was carried out to analyze the single dose toxicity of ShinEumHur (SEH) pharmacopuncture injected into the muscles of Sprague-Dawley rats. Methods: The SEH pharmacopuncture was made in a clean room at the Korean Pharmacopuncture Institute (K-GMP). After the mixing process with sterile distilled water had been completed, the pH was controlled to between 7.0 and 7.5. All experiments were conducted at Biotoxtech, an institution authorized to perform non-clinical studies under the Good Laboratory Practice (GLP) regulations. Sprague-Dawley rats were chosen for the pilot study. Doses of SEH pharmacopuncture, 0.25, 0.5 and 1.0 mL, were administered to the experimental groups, and a dose of normal saline solution, 1.0 mL, was administered to the control group. We examined the survival rate, weights, clinical signs, mean hematology parameters, mean clinical chemistry, necropsy and histopathological findings. This study was conducted under the approval of the Institutional Animal Ethics Committee. Results: No deaths or abnormalities occurred in any of the four groups. No significant changes in weight, hematological parameters or clinical chemistry between the control group and the experimental groups were observed. To check for abnormalities in organs and tissues, we used microscopy to examine representative histological sections of each specified organ; the results showed no significant differences in any of the organs or tissues. Conclusion: The above findings suggest that treatment with SEH pharmacopuncture is relatively safe. Further studies on this subject are needed to yield more concrete evidence.

• Korean Journal of Environmental Biology
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• v.23 no.4
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• pp.398-404
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• 2005

Radioprotection is of practical importance for the normal tissues of tumor patients subject to radiotherapy, people with planned or accidental exposure to radiation, and the public and radiation workers. Since oxygen enhances radiation - induced biological damage, antioxidants should be related with the function as a radioprotectors. Ascorbic acid or caffeine is an essential component and antioxidant in the diet of humans and a small range of other mammals. The present study investigates functional radioprotection of caffeine and ascorbic acid against gamma radiation in irradiated C57BL/6N mice. Eight-week-old male C57BL/6N mice were irradiated with 6.5 Gy. A caffeine treated group was administered with $80mg\;kg^{-1}$ body weight by intraperitoneal injection, a single treatment 1 hr before irradiation. Ascorbic acid was administered $330\;mg\;L^{-1}$ in drinking water through all the experimental period. According to time schedules, animals were sacrificed by cervical dislocation. And the samples were collected 2 weeks after whole- body gamma irradiation. The caffeine treated group showed lower decrement of body and organ weights than the other experimental groups. The qualitative analysis of circulating testosterone in serum was performed by means of radioimmunoassay (RIA). The normal level of circulating testosterone was maintained by the treatment of caffeine and ascorbic acid. The change of weight of body and organ and the appearance of seminiferous tubules were improved by an effect of caffeine or ascorbic acid against irradiation. Taken together, caffeine and ascorbic acid protects impairment of spermatogenesis against gamma radiation and may act as a radio-protector.

• Geomechanics and Engineering
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• v.31 no.6
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• pp.599-614
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• 2022

One of the methods of stabilizing retaining walls, embankments, and deep excavations is the implementation of plate anchors (like the Geolock wall anchor systems). Back-to-back Mechanically Stabilized Earth (BBMSE) walls are common stabilized earth structures that can be used for bridge ramps. But so far, the analysis of the interactive behavior of two back-to-back anchored walls (BBAW) by double-plates anchors (constructed closely from each other and subjected to the limited-breadth vertical loading) including interference of their failure and sliding surfaces has not been the subject of comprehensive studies. Indeed, in this compound system, the interaction of sliding wedges of these two back-to-back walls considering the shear failure wedge of the foundation, significantly impresses on the foundation bearing capacity, adjacent walls displacements and deformations, and their stability. In this study, the effect of horizontal distance between two walls (W), breadth of loading plate (B), and position of vertical loading was investigated experimentally. In addition, the comparison of using single and equivalent double-plate anchors was evaluated. The loading plate bearing capacity and displacements, and deformations of BBAW were measured and the results are presented. To evaluate the shape, form, and how the critical failure surfaces of the soil behind the walls and beneath the foundation intersect with one another, the Particle Image Velocimetry (PIV) technique was applied. The experimental tests results showed that in this composite system (two adjacent-loaded BBAW) the effective distance of walls is about W = 2.5*H (H: height of walls) and the foundation effective breadth is about B = H, concerning foundation bearing capacity, walls horizontal displacements and their deformations. For more amounts of W and B, the foundation and walls can be designed and analyzed individually. Besides, in this compound system, the foundation bearing capacity is an exponential function of the System Geometry Variable (SGV) whereas walls displacements are a quadratic function of it. Finally, as an important achievement, doubling the plates of anchors can facilitate using concrete walls, which have limitations in tolerating curvature.