• Geomechanics and Engineering
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• v.17 no.4
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• pp.355-365
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• 2019

It is normal to observe the presence of numerous cracks in coal body. And it has significantly effective on the mechanical characteristics and realistic failure models of coal mass. Therefore, this paper is to investigate the influence of crack parameters on coal body by comprehensive using theoretical analysis, laboratory experiments and numerical simulation through prepared briquette specimens. Different from intact coal body possessing single peak in stress-strain curve, other specimens with crack angle can be illustrated to own double peaks. Moreover, the unconfined compressive strength (UCS) of specimens decreases and follow by increasing with the increase of crack angle. It seems to like a parabolic shape with an upward opening. And it can be demonstrated that the minimum UCS is obtained in crack angle $45^{\circ}$. In terms of failure types, it is interesting to note that there is a changing trend from tensile failure to tensile-shear mixing failure with tension dominant follow by shear dominant with the increase of crack angle. However, the changing characteristics of UCS and failure forms can be explained by elastic-plastic and fracture mechanics. Lastly, the results of numerical simulations are good consistent with the experimental results. It provides experimental and theoretical foundations to reveal fracture mechanism of coal body with non-penetrating single crack further.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.4
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• pp.577-586
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• 2013

This study investigated black garlic and mugwort extracts have anti-stress activity. The antioxidant activities of extracts from black garlic (BEP), mugwort (MEP), and three mixtures (MPA, 95:5; MPB, 90:10; MPC, 85:15, w/w% for BEP and MEP, respectively) were tested in vitro. DPPH and ABTS radical scavenging activities for the mixtures (MPA, MPB and MPC) were significantly elevated in a dose-dependent manner by the amount of mugwort extract. A restraint stress was imposed on six groups of Sprague-Dawley rats supplemented with an AIN-93 diet (RSC) or one of five kinds of hot water extract drinks containing (black garlic, RS1; mugwort, RS2; and mixtures of black garlic : mugwort at 95:5, RS3; 90:10, RS4, and a mixture of black garlic : mugwort : apple extract : xylitol=90.25:4.75:2:3, RS5; v/v%) for 4 weeks. The normal group was fed with the AIN-93 diet and not exposed to restraint stress. Food intake was higher in the group fed with garlic extract (RS1), while the body weight gain and food efficiency ratio did not significantly change. The total serum cholesterol content in the RS1 and RS2 groups was significantly lower than the RSC group (control), and the RS5 group was not significantly different compared to the RS3 group. The serum triglyceride content was significantly higher RS3~RS5 groups than RS1 and RS2 groups. In terms of HDL-C and LDL-C contents, AI and CRF in the serum were not significantly different between RS3 and RS5 groups. AST and ALP activities of RS1~RS5 groups were significantly lower than the RSC group. The liver total lipid and cholesterol contents of RS1~RS5 groups were significantly lower than RSC group, and triglyceride content was significantly lower in the RS1 group. Glycogen in the liver tissue was significantly higher in the RS2 and RS3 group compared to the RSC group. These results show that the intake of a mixture of black garlic and mugwort extracts may be effective in the alleviation of hyperlipidemia caused by restraint stress.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.6 no.1
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• pp.65-73
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• 1995

We conducted the comparative study of the effects of the parent training combined with medication and the medication only on 23 ADHD children with the age from 5 to 11(body 22, girl 1). Mothers of combined treatment group(parent training+medication) attended, the parent training program once a week for 8 consecutive weeks and booster session 1 month later. Children of both groups were assessed twice before and after treatment using the various using scales and TOVA to evaluate the treatment effects. The results of present study showed the greater effectiveness of the medication+parent training over the medication only in reducing the parenting stress of mothers as well as the inattention and behavioral problems of ADHD children. In medication only group while the scores of mother's rating did not change significantly after treatment, those of teacher's rating and TOVA tend to be decreased to normal range. These results suggested that methylphenidate is effective on improving attentional problems of ADHD children, but not on behaviral problems at home. These results mean that parent training is needed for reducing behavioral problems of ADHD children, negative interactions in mother-child relation, and parenting stress as well as maxmizing medication effect.

• The Journal of the Korea Contents Association
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• v.17 no.2
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• pp.105-112
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• 2017

This study recognizes it as a social problem that can be prevented by basic research on safety security design for the elderly, and aims to clearly analyze risk factors for injury. For this study, raw data from the 6th Korean National Health and Nutrition Survey were employed and analyzed. Their social characteristics were classified with standards including gender, education, EuroQoL(human locomotion, normal activity and pain uncomfortableness), the quality of life(PHQ-(1)(2)(4)), recognition on stress, activity restriction status and associated causes(bone fracture and joint injury). Their epidemiological traits were chronic diseases, 'diabetes and hip-joint pain', and health-behavioral traits were 'smoking, breakfast frequency and high-level physical activity status.' In conclusion, it can be found that damage risk of elderly rose in case of female, lower education, inconvenience or limitation, pain or discomfort in locomotion and daily activities, higher recognition of stress, lower interest in work, feeling of depression, despair, and weariness, restriction in activity caused by bone fracture and joint injury, having diabetes and hip-joint pain, smoking, low frequency in having breakfast and high-level physical activities. Based on this study, we envision that an effective solution for injury risk factors caused by the organic relation can be reached in the near future.

• Journal of Oriental Neuropsychiatry
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• v.21 no.4
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• pp.219-231
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• 2010

Objectives : School refusal is usually considered as individual's behavioral problem. These days. however. the adolescents' school refusal needs some kind of medical approaches because it is related to mental disorder of the adolescents. Due to too much pressure and stress from the competition between classmates and from good performance in school. the number of adolescents who refuse to go to school is increasing. Despite this circumstance. school refusal is neither regarded as a single independent disorder nor endorsed as an officially classified disease. which makes difficult to conduct research on this issue and to establish standardized treatment for it. In addition. there is a lack of research on this topic. especially in oriental medicine. so there is no a case report or study on school refusal. This study is trying to comment on school refusal from the perspective of oriental medicine. Methods : We tried to examine the effect of oriental medicine treatment for school refusal with four adolescent cases. The patients commonly have at least more than one mental disorder (including depression disorder. anxiety disorder. and anorexia nervosa). have some problem with the relationship with their family. in particular with mother. do not have father or not be loved by their father. and have irregular eating habits. Thus. we diagnosed them as qi transforming into fire (氣鬱化矢) spleen-stomach deficiency cold (脾胃虛寒) and heart blood deficiency (心血虛) due to stress from the family issues and unhealthy eating habits. The patients received supportive therapy. family therapy. etc among many oriental mental treatments and their progress had been observed through hospitalization and outpatient treatment. Results : All four cases were reported positive progress on their symptoms and started coming back to school. We also examined whether they were well fitting into the school while they received outpatient treatment. and the results show that all four patients continue to settle down in normal school life. Conclusions : This study closely reviewed the mental disorder of school refusal cases and showed that the Oriental medical treatment was effective in helping the patients come back to school. More future research is required to better treatment for school refusal cases in oriental medicine.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.3
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• pp.294-301
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• 2008

This study was carried out to investigate the protective effects and detoxification of oriental herb extracts mixture (Saururus chinensis, Taraxacum platycarpum, Ulmus macrocarpa, Glycyrrhiza glabra, Rhynchosia nulubilis) on TCDD-induced oxidative stress. Thirty five male rats were divided into 5 groups: normal control group received saline; vehicle control group received DMSO and acetone; only TCDD-treated group received multiple intraperitoneal injection of TCDD ($100{\mu}g/kg$) and saline; post-treated group of OHEM (400 mg/kg/day) received oral administration for 5 weeks after TCDD treatment; and pre-treated group of OHEM (400 mg/kg/day) received oral administration for 6 weeks from 1 week before TCDD treatment. The elevated serum activities of alanine transaminase (AST), aspartate transaminase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH) and atherorganic index due to TCDD were significantly decreased by the treatment of OHEM (p<0.05); the pre-treatment of OHEM was especially effective. Hydropic lesions and cytoplasmic vacuolizations in the liver of TCDD-treated rats were inhibited by the treatment of OHEM. Also, OHEM treatment reduced edemas in small intestine villus of TCDD-treated rats. These results suggest that OHEM from various oriental herb extracts might be a useful protective and detoxification agent against TCDD.

• Composites Research
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• v.36 no.4
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• pp.253-258
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• 2023

Although the development of transportation means has realized the right to mobility for the disabled who have difficulty in moving, it can be said that the improvement of the safety of passengers with disabilities that can occur in a car accident is lower than that of ordinary passenger seats. In particular, in the case of a rear-end collision that can occur suddenly, it is a reality that disabled passengers are vulnerable to head and neck injuries. Therefore, in this study, a multi-layer headrest foam that divides the headrest into three parts in the coronal plane was proposed to improve the head and neck injury index of disabled passengers in the vehicle in the event of a rear-end collision of a wheelchair transport vehicle. A range of stress scale factors was selected to give various compressive characteristics of the foam through low-speed rear-end collision analysis through a simple model, and GA optimization was performed by specifying the range as a parameter. Through the optimization result, the phase relationship between HIC and NIC was analyzed according to the compression characteristics of the layers. HIC responded most sensitively to the compression characteristics of the front layer and NIC responded to the compression characteristics of the mid layer, and the compression characteristics of the rear layer showed the lowest. A normal headrest and an optimized multi-layer headrest were placed in the validation model to analyze the low-speed rear-end collision sled test, and HIC and NIC were derived lower in the multi-layer headrest than in the general headrest. The compression behavior of the multi-layer headrest was also clearly shown, and it was verified that the multi-layer headrest was effective in improving the injury index of the head and neck compared to the general headrest.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.1
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• pp.125-129
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• 2016

Background: Patients with differentiated thyroid cancers (DTC) who receive radioactive iodine-131 (RAI) are released from isolation when their dose rate is below the regulatory requirements. The purpose of this study was establish predicting factors for early release from the isolation facility after RAI administration in patients with DTC. Materials and Methods: This was a prospective study which included 96 (58 females and 38 males) patients with DTC who had received RAI from April 2013 till August 2015. The study was duly approved by the ethical committee of the institute. Patients who had complete information of primary tumor size (PTS), serum TSH, stimulated thyroglobulin level [sTg] with antibodies (IU/ml) at the time of RAI treatment were included. All had a normal serum creatinine level. To attain lower effective half-life good hydration and administration of soft laxative were ensured. Dose rate was measured (immediately, 24 h and 36 h) at 1 meter distance from anterior mid trunk and a dose rate <$50{\mu}Sv/h$ was considered as the releasing criterion. At 24 h 50 patients were released while the remaining 46 patients were released at 36 h. A post-ablative whole body scan (PA-WBIS) was performed 5-8 days after RAI ablation in all patients. Results: Patients released after 24 h were significantly younger, had smaller lesions with higher proportion of papillary cancer, lower sTg, lower sTg/TSH ratio and had received a lower dose of RAI as comapred to those who were discharged after 36 h. Serum TSH and gender were not found to have any significant correlation between two cohorts. ROC and multivariate analysis have shown age ${\leq}37years$, PTS ${\leq}3.8cm$, $RAI{\leq}150mCi$, $sTg{\leq}145ng/ml$ and $sTg/TSH{\leq}1.085$ as strong indepedent predictors for early release. Conclusions: We conclude that younger age (${\leq}37years$), smaller tumor size (${\leq}3.8cm$), lower RAI dose (${\leq}150mCi$), lower sTg (${\leq}145ng/ml$) and a lower sTg/TSH ratio (${\leq}1.085$) are significant independent predictors for release at 24 h after RAI treatment in DTC patients. Effective utilization of these factors could help the treating physicians to use limited number of internment facilities with higher throughput, lower cost and lower psychological stress to patients.

• Journal of Korean Society of Steel Construction
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• v.15 no.3
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• pp.231-239
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• 2003

Many box girder bridges have been constructed during the past several decades due to their large bending and torsional rigidities as well as aesthetic considerations. However, box girders have shortcoming in that the cross section distorts under an eccentric loading and warps out of the section plane. Therefore, in order to reduce distortional stresses such as distortional warping and transverse bending normal stresses, diaphragms were generally installed in the box girders. Shapes of the diaphragms in steel-box-girder bridges constructed up to date were solid-plate, frame, and truss types. The objectives of this study using parametric study were to evaluate the appropriate stiffness ratio of intermediate diaphragms and then to propose the effective spacing and numbers of intermediate diaphragms based on the evaluated stiffness ratio. Target bridges for this study were straight continuous span bridges with a single-cell steel box section. The parameters for the parametric study were the shape of box section, the span numbers, the equivalent span length, the stiffness of intermediate diaphragms, and the spacing of intermediate diaphragms. From the results of the parametric study, the effective spacing and numbers as well as the stiffness ratio of the intermediate diaphragms will be presented.

• Archives of Plastic Surgery
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• v.36 no.5
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• pp.531-537
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• 2009

Purpose: Alveolar bone grafting has become an essential process in the treatmemt of alveolar cleft patient for stabilization of the maxillary arch, elimination of oronasal fistula, the reconstruction of the soft tissue nasal base support, and creation of bony support for tooth eruption for implant. The use of Autologous iliac cancellous bone is preferable because of the adequate quantity and high osteoinductive potential. However, even with iliac bone, insufficient osteoregeneration and absorption occur due to several factors such as the patient's age, cleft width, functional stress, and others. In order to increase osteoregeneration where the iliac bone is placed, the present study is associated with bone marrow aspirate (BMA). The experimental study evaluated the efficacy of osteoregeneration in normal cleft rabbits when alveolar bone grafting was performed with autologous iliac corticocancellous bone. Methods: Twenty - four New Zealand White rabbits were divided randomly into 2 groups (BMA, control). All animals underwent harvesting of corticocancellous bone graft from the right posterior iliac crest via standard surgical technique. $1m{\ell}$ of BMA were obtained by scraping the needle and aspirate with $10m{\ell}$ syringe from the contralateral iliac bone wall. The muco - periosteal flap on the palate was elevated. A mixture of Equal bone's volumes with BMA and saline as its control was inserted into the cleft. Animals were sacrificed at 2, 4, and 8 weeks and maxilla was harvested for dental peri - apical X-ray, bone matrix density (BMD),and histologic analysis. Result: BMD of regenerated bone to the cleft in the rabbits was higher than that of the control rabbits. X-ray, histologic analysis showed that increased osteoregeneration and low absorption rate were observed in the BMA group. Conclusion: Our experimental study showed BMA enhanced the osteoregeneration and survival rate of alveolar bone grafting. BMA is easy to extract & cost - time effective. So it can be an effective enhancers for bone grafting mixtures.