• Advances in nano research
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• 제14권2호
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• pp.141-154
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• 2023

Effects of viscoelastic foundation on vibration of curved-beam structure with clamped and simply-supported boundary conditions is investigated in this study. In doing so, a micro-scale laminate composite beam with two piezoelectric face layer with a carbon nanotube reinforces composite core is considered. The whole beam structure is laid on a viscoelastic substrate which normally occurred in actual conditions. Due to small scale of the structure non-classical elasticity theory provided more accurate results. Therefore, nonlocal strain gradient theory is employed here to capture both nano-scale effects on carbon nanotubes and microscale effects because of overall scale of the structure. Equivalent homogenous properties of the composite core is obtained using Halpin-Tsai equation. The equations of motion is derived considering energy terms of the beam and variational principle in minimizing total energy. The boundary condition is assumed to be clamped at one end and simply supported at the other end. Due to nonlinear terms in the equations of motion, semi-analytical method of general differential quadrature method is engaged to solve the equations. In addition, due to complexity in developing and solving equations of motion of arches, an artificial neural network is design and implemented to capture effects of different parameters on the inplane vibration of sandwich arches. At the end, effects of several parameters including nonlocal and gradient parameters, geometrical aspect ratios and substrate constants of the structure on the natural frequency and amplitude is derived. It is observed that increasing nonlocal and gradient parameters have contradictory effects of the amplitude and frequency of vibration of the laminate beam.

• Asian Pacific Journal of Cancer Prevention
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• 제16권18호
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• pp.8573-8578
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• 2016

Background: This study was guided by principles of the theoretical system of evidence-based medicine. In particular, when searching for evidence of breast cancer, a measuring scale is an instrument for evaluating curative effects in accordance with the laws and characteristics of medicine and exploring the establishment of a system for medically assessing curative effects. At present, there exist few tools for evaluating curative effects. Patient-reported outcomes (PROs) refer to outcomes directly reported by patients (without input or explanations from doctors or other intermediaries) with respect to all aspects of their health. Data obtained from PROs provide evidence of treatment effects. Materials and Methods: In accordance with the tenets of theoretical medicine and ancient medical theory regarding breast cancer, principles for developing a PRO scale were established, and a theoretical model was developed and a literature review was performed, items from this pool were combined and split, and an initial scale was constructed. After a pilot survey and additional modifications, a pre-questionnaire scale was formed and used in a field investigation. After the application of statistical methods, the item pool was used to create a formal scale. The reliability, validity and feasibility of this formal scale were then assessed. Results: In a clinical investigation, 479 responses were recovered, with an acceptance rate of 95%. a combination of various methods was employed, and the items that were selected by all methods or more than half of the methods were employed in the questionnaire. In these cases, the screening methods were combined with certain features of the item, A total of four domains and 38 items were reserved. The reliability analysis indicated that the PRO scale was relatively reliable. Conclusions: Scientific assessment proved that the proposed scale exhibited good reliability and validity. This scale was readily accepted and could be used to assess the curative effects of medical therapy. However, given the limited scope of this investigation, the capacity for adapting this scale to incorporate other theories could not be determined.

• Smart Structures and Systems
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• 제21권3호
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• pp.279-286
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• 2018

The free longitudinal vibration of a circular truncated nanocone is investigated based on the nonlocal elasticity theory. Exact analytical formulations for tapered nanostructures are derived and the nonlinear differential governing equation of motion is developed. The nonlocal small scale effect unavailable in classical continuum theory is addressed to reveal the long-range interaction of atoms implicated in nonlocal constitutive relation. Unlike most previous studies applying the truncation method to the infinite higher-order differential equation, this paper aims to consider all higher-order terms to show the overall nonlocality. The explicit solution of nonlocal stress for longitudinal deformation is determined and it is an infinite series incorporating the classical stress derived in classical mechanics of materials and the infinite higher-order derivative of longitudinal displacement. Subsequently, the first three modes natural frequencies are calculated numerically and the significant effects of nonlocal small scale and vertex angle on natural frequencies are examined. The coupling phenomenon of natural frequency is observed and it is induced by the combined effects of nonlocal small scale and vertex angle. The critical value of nonlocal small scale is defined, and after that a new proposal for determining the range of nonlocal small scale is put forward since the principle of choosing the nonlocal small scale is still unclear at present. Additionally, two different types of nonlocal effects, namely the nonlocal stiffness weakening and strengthening, reversed phenomena existing in nanostructures are observed and verified. Hence the opposite nonlocal effects are resolved again clearly. The nano-engineers dealing with a circular truncated nanocone-based sensors and oscillators may benefit from the present work.

• 종양간호연구
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• 제9권2호
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• pp.86-94
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• 2009

Purpose: This study was aimed to identify the influencing factors on hope in the patients suffering with breast cancers. Methods: The subjects were 150 women who were diagnosed with breast cancer at three university hospitals and a general hospital. Data collection was conducted by hope scale, family support scale, self esteem scale, depression scale, pain scale, and fatigue scale. The collected data were analyzed using frequency, percentage, t-test, ANOVA, Pearson's correlation coefficients, and stepwise multiple regression. Results: Level of hope in the participants was high. There were a significant correlation among hope, family support, effects of religion, self esteem, depression, pain and fatigue. There were significant differences in hope by the age, education level, and cost burden. The most powerful predictor of hope was self esteem (38.2%). Altogether family support, effects of religion, depression, and fatigue explained 50.4% of hope of the participants. Conclusion: The findings of the study suggested that the concepts of self esteem, family support, effects of religion, depression and fatigue should be considered important factors in developing hope promoting program for breast cancer patients.

• 대한한방부인과학회지
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• 제18권1호
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• pp.156-168
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• 2005

Objective : The purpose of this study is to identify the clinical effects of Chiljehyangbuhwan in the treatment of dysmenorrhea patients. Methods : We studied fifty patients who visited Kyung Hee University Oriental Medical Center from July, 2004 to August, 2004. Women with organic disease such as ut. myoma, ov. cyst and pelvic inflammatory disease were excluded from this study. We treated them with Chiljehyangbuhwan for one menstrual cycle. The severity of dysmenorrhea were measured by MVRS (Multidimensional Verbal Rating scale), VRS (Verbal Rating scale) and VAS (Visual Analog Scale). Results : Chiljehyangbuhwan significantly decreased the severity of dysmenorrhea. Furthermore Chiljehyangbuhwan had an effect on dysmenorrhea for next menstrual cycle without taking. Chiljehyangbuhwan did not show hepatic and renal virulence. Conclusion : This study shows that Chiljehyangbuhwan has remarkable effects on dysmenorrhea patients and that effects continue to next menstrual cycle without taking medicine.

• KSBB Journal
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• 제13권6호
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• pp.700-705
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• 1998

Studies were made to investigate effects of the scale-up of stirred tank bioreactors on cell growth and alkaloids production for suspension cultures of Eschscholtzia californica. In the 1.5 L STR, cell lysis was observed at 110 rpm or higher agitation speed. The agitation speed of 30 L STR was 43.7 rpm to maintain the same shear stress developed in 1.5 L STR of 100 rpm. As a result of scale-up from 1.5 L to 30 L STR, the specific growth rate was decreased from 0.12 to 0.07 day-1. The alkaloids productivity was also decreased from 0.24 to 0.14 mg/L-day. Changes of mixing performance and oxygen transfer were studied to explain the decrease of cell growth and alkaloids production. Decreased oxygen transfer rate coefficient(KLa) and increased mixing time by the scale-up was observed at various aeration rates.

• The Journal of Korean Physical Therapy
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• 제28권6호
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• pp.364-368
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• 2016

Purpose: The purpose of this study is to investigate effects of psychological factors on Schroth exercise and Pilates exercise to female high school students with idiopathic scoliosis. Methods: Sixteen subjects with over 20 of Cobb's angle were randomly divided into Schroth exercise group (SEG, n=8) and Pilates exercise group (PEG, n=8). Both training programs were carried out 3 day a week for 12 weeks. Psychological factors were measured using depression scale, self esteem scale and body esteem scale. Results: Both groups showed significant differences in depression scale, self esteem scale and body esteem scale. Schroth exercise group showed greater improvement than Pilates group. Conclusion: Having correct body image affects psychological factors to growing students. Schroth exercise is more effective method to physical and psychological approach of idiopathic scoliosis.

• 대한토목학회논문집
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• 제7권3호
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• pp.111-119
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• 1987

해안구조물(海岸構造物)의 안정성(安定性)과 사면상(斜面上)의 반사파(反射波), run-up, run-down 등 흐름특성(特性)에 대한 모형(模型)의 축척효과(縮尺効果) 발생(發生) 메카니즘과 그 제어(制御) 방법(方法)을 7종(種)의 축척모형(縮尺模型)에 의해 실험적(實驗的)으로 연구(硏究)하였다. 그 결과(結果), 종래(從來)의 많은 연구자(硏究者)들이 소홀히 해 왔던 구조물(構造物) 내부(內部)의 침투류(浸透流) 특성(特性)의 상사(相似) 여부(如否)가 축척효과(縮尺効果) 발생(發生)의 가장 중요(重要)한 요인(要因)임을 지적(指摘)하였다. 해안구조물(海岸構造物) 가운데서 특히 투과성(透過性) 구조물(構造物)의 축척효과(縮尺効果) 제어(制御)를 위해서는 피복층(被覆層), filter층(層), 피복층(被覆層)에 가까운 core부(部)의 침투류(浸透流) Reynolds수(數)가 각각(各各) Re > $2{\times}10^4$, $Re_f$ > $3{\times}10^3$, $Re_c$ > $1{\times}10^3$인 조건(條件)을 만족하도록 구조물(構造物) 각(各) 층(層)의 축척(縮尺)을 결정(決定)하는 것이 바람직함을 강조(强調)하였다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2013년도 제46회 KOSCO SYMPOSIUM 초록집
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• pp.97-98
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• 2013

Flame behaviors in meso-scale rectangular channels are largely influenced by heat recirculation through wall. In order to investigate the effects of wall thermal property on the heat recirculation and flame behaviors, meso-scale rectangular channels, of which upper and lower walls are made of quartz, stainless steel and silicon carbide and front and rear walls of quartz for flame visualization, were fabricated in this study. As a result, characteristic mixture velocities of propane-air flame, such as transition, stationary, and instability onset velocities, were measured for each channel and various mixture conditions. The results show that thermal conductivity has a close relationship to the characteristic velocities.

• Steel and Composite Structures
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• 제39권5호
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• pp.565-581
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• 2021

In this paper the buckling analysis of the nanoplate made of arbitrary bi-directional functionally graded (BDFG) materials with small scale effects are investigated. To study the small-scale effects on buckling load, the Eringen's nonlocal theory is applied. Employing the principle of minimum potential energy, the governing equations are obtained. Generalize differential quadrature method (GDQM) is used to solve the governing equations for various boundary conditions to obtain the buckling load of BDFG nanoplates. These models can degenerate into the classical models if the material length scale parameter is taken to be zero. Comparison between the results of GDQ method and other papers for buckling analysis of a simply supported rectangular nano FGM plate reveals the accuracy of GDQ method. At the end some numerical results are presented to study the effects of material length scale parameter, plate thickness, aspect ratio, Poisson's ratio boundary condition and side to thickness ratio on size dependent Frequency.