• Steel and Composite Structures
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• 제33권6호
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• pp.805-822
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• 2019

In this work, a simple four-variable integral plate theory is employed for examining the thermal buckling properties of functionally graded material (FGM) sandwich plates. The proposed kinematics considers integral terms which include the effect of transverse shear deformations. Material characteristics and thermal expansion coefficient of the ceramic-metal FGM sandwich plate faces are supposed to be graded in the thickness direction according to a "simple power-law" variation in terms of the "volume fractions" of the constituents. The central layer is always homogeneous and consists of an isotropic material. The thermal loads are supposed as uniform, linear, and nonlinear temperature rises within the thickness direction. The influences of geometric ratios, gradient index, loading type, and type sandwich plate on the buckling properties are examined and discussed in detail.

• Advances in nano research
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• 제3권1호
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• pp.29-37
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• 2015

In the current study, the nonlinear vibration properties of an embedded zigzag single-walled carbon nanotube (SWCNT) are investigated. Winkler-type model is used to simulate the interaction of the zigzag SWCNTs with a surrounding elastic medium. The relation between deflection amplitudes and resonant frequencies of the SWCNT is derived through harmonic balance method. The equivalent Young's modulus and shear modulus for zigzag SWCNT are derived using an energy-equivalent model. The amplitude - frequency curves for large-amplitude vibrations are graphically illustrated. The simulation results show that the chirality of zigzag carbon nanolube as well as surrounding elastic medium play more important roles in the nonlinear vibration of the single-walled carbon nanotubes.

• Advances in nano research
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• 제7권2호
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• pp.89-98
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• 2019

In this work, the thermal buckling characteristics of zigzag single-walled boron nitride (SWBNNT) embedded in a one-parameter elastic medium modeled as Winkler-type foundation are investigated using a nonlocal first-order shear deformation theory (NFSDT). This model can take into account the small scale effect as well as the transverse shear deformation effects of nanotubes. A closed-form solution for nondimensional critical buckling temperature is obtained in this investigation. Further the effect of nonlocal parameter, Winkler elastic foundation modulus, the ratio of the length to the diameter, the transverse shear deformation and rotary inertia on the critical buckling temperature are being investigated and discussed. The results presented in this paper can provide useful guidance for the study and design of the next generation of nanodevices that make use of the thermal buckling properties of boron nitride nanotubes.

• 패션비즈니스
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• 제8권3호
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• pp.84-113
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• 2004

The purpose of this study is to provide for some basic data useful to production of the apparels fit and measured well for the Chinese men. For this purpose, Chinese men's apparel measurements and specifications were determined per area group(Beijing and Shanghai) according to the Men's Wear Specifications (GB/T 1335.1-1997), National Standards of People's Republic of China. The results of this study can be summarized as follows; 1. As a result of dividing the Chinese men into Beijing and Shanghai men and thereby, setting stature and upper chest circumference for upper garments and stature and waist for lower garments. 2. As a result of analyzing the correlational distributions of stature and upper chest circumference measurements by region (Beijing and Shanghai) and type of physique, it was found that the coverage rate of the selected sizes was higher in Shanghai sample than Beijing sample in case of the sample with thicker waist circumferences. 3. As a results of analyzing the correlations according to the three-fold classifications of stature /upper chest circumference/waist for garment specifications by region (Beijing and Shanghai) and type of physique, "A" type was most covered, followed by "B", "C" and "Y" types.

• Smart Structures and Systems
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• 제21권4호
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• pp.397-405
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• 2018

In this paper, a novel simple shear deformation theory for buckling analysis of single layer graphene sheet is formulated using the nonlocal differential constitutive relations of Eringen. The present theory involves only three unknown and three governing equation as in the classical plate theory, but it is capable of accurately capturing shear deformation effects, instead of five as in the well-known first shear deformation theory (FSDT) and higher-order shear deformation theory (HSDT). A shear correction factor is, therefore, not required. Nonlocal elasticity theory is employed to investigate effects of small scale on buckling of the rectangular nano-plate. The equations of motion of the nonlocal theories are derived and solved via Navier's procedure for all edges simply supported boundary conditions. The results are verified with the known results in the literature. The influences played by Effects of nonlocal parameter, length, thickness of the graphene sheets and shear deformation effect on the critical buckling load are studied. Verification studies show that the proposed theory is not only accurate and simple in solving the buckling nanoplates, but also comparable with the other higher-order shear deformation theories which contain more number of unknowns.

• Advances in aircraft and spacecraft science
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• 제5권6호
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• pp.633-652
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• 2018

The present paper focuses on the development of a model for simulating the thermoelectric behavior of CNTs/CFRP Organic Matrix Composite (OMC) laminates for aeronautical applications. The model is developed within the framework of the thermodynamics of irreversible processes and implemented into commercial ABAQUS Finite Element software and validated by comparison with experimental thermoelectric tests on two types of composites materials, namely Type A with Carbon Nanotubes (CNT) and Type B without CNT. A simplified model, neglecting heat conduction, is also developed for simplifying the identification process. The model is then applied for FEM numerical simulation of the thermoelectric response of aircraft panel structures subjected to electrical loads, in order to discuss the potential danger coming from electrical solicitations. The structural simulations are performed on quasi-isotropic stacking sequences (QI) $[45/-45/90/0]_s$ using composite materials of type A and type B and compared with those obtained on plates made of metallic material (aluminum). For both tested cases-transit of electric current of intermediate intensity (9A) and electrical loading on panels made of composite material-higher heating intensity is observed in composites materials with respect to the corresponding metallic ones.

• Geomechanics and Engineering
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• 제11권2호
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• pp.289-307
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• 2016

A simple hyperbolic shear deformation theory taking into account transverse shear deformation effects is proposed for the free flexural vibration analysis of thick functionally graded plates resting on elastic foundations. By considering further supposition, the present formulation introduces only four unknowns and its governing equations are therefore reduced. Hamilton's principle is employed to obtain equations of motion and Navier-type analytical solutions for simply-supported plates are compared with the available solutions in literature to check the accuracy of the proposed theory. Numerical results are computed to examine the effects of the power-law index and side-to-thickness ratio on the natural frequencies.

• 여성건강간호학회지
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• 제14권2호
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• pp.93-103
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• 2008

Purpose: This descriptive study was to explore the factors relating to Social Physique Anxiety(SPA) in the adolescent girls(N=700). These factors included the biological(level of school[age], period of menstruation, and BMI), the sociocultural(Influence of Mass Media, [IMM], Stereotype of Ideal Female Body[SIFB], type of school, perceived figure, and ideal figure) and the BW control-related factors(experience of bodyweight [BW] control, satisfaction at the result of BW control, and motive of BW control). Method: The sample was 700 girls of the middle and high schools in Jeju-do. The data was collected by the self-reported questionnaire and processed with the SPSS Win 12.0 program. Result: 26% of the variance in SPA was explained by the biological factors(level of school) and the sociocultural factors (perceived figure, ideal figure, type of school, and IMM). SPA, IMM, and SIFB were significantly correlated with each others(r=1,65-2.92, p<.05). The mean SPA scores according to BW control-related factors were significantly different. Conclusion: This results suggest that media education is necessary to reduce or eliminate the adolescent girl's SPA. In addition, SPA needs to be considered as the important concept for the future nursing researches and interventions related to BW control.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 V
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• pp.2693-2696
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• 2003

우리나라의 국민표준체위조사는 1979년 1차 조사를 시작으로 약 5-6년 주기로 실시되고 있으며, 1997년 제 4차 조사가 실시되었다. 국민체위조사 결과를 기반으로 의류, 신발, 가구 등 관련산업의 제품설계에 반영되었다. 본 논문에서는 국민표준체위조사 결과 자료를 기본으로 성별, 연령별, 체형별로 사용자를 분류한 후 체형별 분류를 위한 인체 측정치를 도출하였다. 도출된 인체측정치의 상관관계 분석, 대표적인 항목 도출 등의 과정을 통하여 3D 캐릭터를 구성하였다. 구성을 위한 과정으로 골프, 테니스 등의 스포츠 동작을 효율적으로 나타낼 수 있는 인체 측정치를 도출하였다. 항목이 결정되면 각 타입의 3D 캐릭터를 구성 할 수 있는 치수를 제시하여 생성하였다. 스포츠의 자세 및 동작분석에 대한 이론적 접근에서 가시적인 정보제공 및 자세·동작분석 프로토콜을 개발함으로서 자세 및 동작에 대한 정량적, 객관적 평가가 가능해졌다.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2006년도 추계 종합학술대회 논문집
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• pp.631-634
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• 2006

우리나라의 국민표준체위조사는 1979년 1차 조사를 시작으로 약 5-6년 주기로 실시되고 있다. 국민체위조사 결과를 기반으로 의류, 신발, 가구 등 관련 산업의 제품 설계에 반영되었다. 본 논문에서는 국민표준 체위조사 결과 자료를 기본으로 성별, 연령별, 체형별로 사용자를 분류한 후 체형별 분류를 위한 인체측정치를 도출하였다. 도출된 인체측정치의 상관관계를 분석, 대표적인 항목 도출 등의 과정을 통하여 3D 캐릭터를 구성하였다. 구성을 위한 과정으로 골프, 테니스 등의 스포츠 동작을 효율적으로 나타낼 수 있는 인체 측정치를 도출하였다. 항목이 결정되면 각 타입의 3D 캐릭터를 구성 할 수 있는 치수를 제시하여 생성하였다. 스포츠의 자세 및 동작 분석에 대한 이론적 접근에서 가시적인 정보제공 및 자세 동작분석 프로토콜을 개발함으로서 자세 및 동작에 대한 정량적, 객관적 평가가 가능해졌다.