• 제목/요약/키워드: structural dimension

검색결과 530건 처리시간 0.026초

Design approach of high damping rubber bearing for seismic isolation

  • Tiong, Patrick L.Y.;Kelly, James M.;Or, Tan T.
    • Smart Structures and Systems
    • /
    • 제20권3호
    • /
    • pp.303-309
    • /
    • 2017
  • Structural control through seismic isolation using elastomeric rubber bearing, which is also known as High Damping Rubber Bearing (HDRB), has seen an increase in use to provide protective from earthquake, especially for new buildings in earthquake zones. Besides, HDRB has also been used in structural rehabilitation of older yet significant buildings, such as museums and palaces. However, the present design approach applied in normal practice has often resulted in dissimilar HDRB dimension requirement between structural designers and bearing manufacturers mainly due to ineffective communication. Therefore, in order to ease the design process, most HDRB manufacturers have come up with catalogs that list all necessary and relevant product lines specifically for structural engineers to choose from. In fact, these catalogs contain physical dimension, compression property, shear characteristic, and most importantly, the total rubber thickness. Nonetheless, other complicated issues, such as the relationship between target isolation period and displacement demand (which determines the total rubber thickness), are omitted due to cul-de-sac fixing of these values in the catalogs. As such, this paper presents a formula, which is derived and extended from the present design approach, in order to offer a simple guideline for engineers to estimate the required HDRB size. This improved design formula successfully minimizes the discrepancies stumbled upon among structural designers, builders, and rubber bearing manufacturers in terms of variation order issue at the designing stage because manufacturer of isolator is always the last to be appointed in most projects.

Structural complexity of the craniofacial trabecular bone in multiple myeloma assessed by fractal analysis

  • Michels, Mariane;Morais-Faria, Karina;Rivera, Cesar;Brandao, Thais Bianca;Santos-Silva, Alan Roger;Oliveira, Matheus L
    • Imaging Science in Dentistry
    • /
    • 제52권1호
    • /
    • pp.33-41
    • /
    • 2022
  • Purpose: This study aimed to evaluate the structural complexity of craniofacial trabecular bone in multiple myeloma by fractal analysis of panoramic and lateral skull radiography, and to compare the fractal dimension values of healthy patients (HPs), pre-treatment patients (PTPs), and patients during bisphosphonate treatment (DTPs). Materials and Methods: Pairs of digital panoramic and lateral skull radiographs of 84 PTPs and 72 DTPs were selected. After application of exclusion criteria, 43 panoramic and 84 lateral skull radiographs of PTPs, 56 panoramic and 72 lateral skull radiographs of DTPs, and 99 panoramic radiographs of age- and sex-matched HPs were selected. The fractal dimension values from panoramic radiographs were compared among HPs, PTPs, and DTPs and between anatomical locations within patient groups using analysis of variance with the Tukey test. Fractal dimension values from lateral skull radiographs were compared between PTPs and DTPs using the Student t-test. Pearson correlation coefficients were used to assess the relationship between the mandible from panoramic radiographs and the skull from lateral skull radiographs. Intra-examiner agreement was assessed using intraclass correlation coefficients (α=0.05). Results: The fractal dimension values were not significantly different among HPs, PTPs, and DTPs on panoramic radiographs or between PTPs and DTPs on lateral skull radiographs (P>0.05). The mandibular body presented the highest fractal dimension values (P≤0.05). The fractal dimension values of the mandible and skull in PTPs and DTPs were not correlated. Conclusion: Fractal analysis was not sensitive for distinguishing craniofacial trabecular bone complexity in multiple myeloma patients using panoramic and lateral skull radiography.

Probabilistic dynamic analysis of truss structures

  • Chen, J.J.;Che, J.W.;Sun, H.A.;Ma, H.B.;Cui, M.T.
    • Structural Engineering and Mechanics
    • /
    • 제13권2호
    • /
    • pp.231-239
    • /
    • 2002
  • The problem of dynamic analysis of truss structures based on probability is studied in this paper. Considering the randomness of both physical parameters (elastic module and mass density) of structural materials and geometric dimension of bars respectively or simultaneously, the stiffness and mass matrixes of the elements and structure have been built. The structure dynamic characteristic based on probability is analyzed, and the expressions of numeral characteristics of inherence frequency random variable are derived from the Rayleigh's quotient. The method of structural dynamic analysis based on probability is developed. Finally, two examples are given.

의류제품의 소비감정에 대한 구조 분석 (Structural Analysis of Consumption Emotions on Apparel Products)

  • 박은주;소귀숙
    • 복식문화연구
    • /
    • 제11권2호
    • /
    • pp.219-230
    • /
    • 2003
  • The purpose of this study was to analyze the structure of consumption emotions that consumers experienced in the process of consuming apparel products. Data was collected from 144 female college students living in Busan, and analyzed by salience, diversity, H-index, Clamor's V, and multi-dimensional scaling. The results showed as following; 1. The consumption emotions related to apparel products appeared three dimensions; ‘Relaxed-tense’ dimension, ‘Pleasant-unpleasant’ dimension, and ‘Outward-inward’ dimension. Considering elements of consumption system, the dimensions of consumption emotions in relation to apparel performances were 'Pleasant-unpleasant' and ‘Outward-inward’. The dimensions of consumption emotions experienced in usage situations were ‘Relaxed-tense’ and ‘pleasant-unpleasant’. The consumption emotions related to specific products were composed of ‘Pleasant-unpleasant’ dimension and ‘Outward-inward’ dimension. 2. As the multi-dimension map of this study has much space, it suggested that the scope of consumption emotions related to apparel products was more limited than those related to general situations and products. 3. The structure of consumption emotions in relation to apparel performances appeared to be bisected, while those related to usage situations showed relatively to be dispersed. 4. Although Pleasant-unpleasant dimension was consistent with results of prestudies, the dimensions of ‘Relaxed-tense’ and ‘Outward-inward’ were newly confirmed as the dimensions of consumption emotions related to apparel products. Therefore, consumer's consumption emotions of apparel products were composed of three dimensions, tended to be more limited than those of general consumption situations and products, and differentiated across apparel performances, usage situation, and specific products.

  • PDF

BtoB 기업간 형성된 사회적 자본이 기업성과에 미치는 영향에 관한 연구 - 지식흡수역량의 매개적 조절효과를 중심으로 - (A Study on the Influence of Social Capital on the Firm's Performance - Focusing on the Mediated moderation effect of Knowledge Absorption Capacity -)

  • 엄성원;임병학
    • 경영과정보연구
    • /
    • 제36권5호
    • /
    • pp.175-193
    • /
    • 2017
  • 본 연구는 BtoB 기업 간 거래에서 형성된 사회적 자본(social capital)이 기업성과에 미치는 영향을 지식흡수역량의 매개적 조절효과를 중심으로 연구모형을 검증하였다. 즉, 사회적 자본의 각각의 차원이 기업성과에 어떠한 영향을 미치는지를 검증하였다. 기존선행연구에서 제시하지 않은 사회적 자본의 각 차원간의 관계를 검증함으로써 사회적 자본 중 어떠한 요소가 기업성과에 영향을 미치는지를 확인하였다. 또한 지식흡수능력에 따라 기업성과에 미치는 영향에 대해 다양한 방법으로 분석하여 제시하였다. 연구결과를 요약하면 다음과 같다. 첫 번째, 사회적 자본을 3가지 차원으로 구분하였다. 즉, 구조적 차원, 관계적 차원 그리고 인지적 차원으로 구분하여 각 구성요소간의 관계를 검증하였다. 먼저 구조적 차원이 관계적 차원에 영향을 미쳤으며, 관계적 차원이 인지적 차원에 긍정적인 영향을 미치는 것으로 나타났으며 마지막으로 구조적 차원 또한 인지적 차원에 영향을 미치는 것으로 나타났다. 이는 선행연구에서 한계점으로 지적되었던 것을 검증했다는 것에 의미가 있다. 두 번째, 사회적 자본의 각각의 구성요소들이 지식흡수역량에 긍정적인 영향을 미치는 것으로 나타났다. 마지막으로 지식흡수역량이 기업성과에 긍정적인 영향을 미치는 것으로 나타났으며 지식흡수역량의 중요성을 확인한 결과 사회적 자본과 기업성과 사이에서의 매개된 조절 효과도 있음을 확인하였다. BtoB 거래에서 축적된 사회적 자본을 어느 정도 흡수하는가에 따라 두 기업의 성과는 분명 다를 수 있음을 의미한다.

만성질환으로 인한 가족기능 변화 모형 - 완성된 확장기 가족을 대상으로 - (Model Development of Change of Family Functioning with Chronic illness)

  • 이은옥;;박영숙;송미순;이인숙;박연환
    • 대한간호학회지
    • /
    • 제29권3호
    • /
    • pp.467-484
    • /
    • 1999
  • The main objectives of this study were to investigate the concept of family function from the perspective of the contemporary Korean family, and to construct model of change of family function with chronic illness. The hybrid model approach was applied in which three phases(theoretical phase, empirical phase, and analytic phase) of concept development were explored for family functioning. The study was conducted from 1997 to 1998. In empirical phase, two groups of purposive samples were drawn : normal family group composed of six families without ill family member, and ill family group composed of seven families of which wives have rheumatoid arthritis. Only families with child(or children) in primary or secondary schools were included in the study. The results were as follows : In theoretical phase, six dimensions of family concept were emerged : affective, structural, control, cognitive, financial, and reproductive dimension. In order to analyse the Korean normal family function in middle class with middle-aged women, financial and reproductive dimension were not included. In empirical phase, five dimensions(affective, structural, control, cognitive, and external relationship) were found from the normal family data. External relationship dimension is very important factor as a resource of the support, especially when their parents or siblings had no help or support to them. In the affective dimension, Korean family emphasized harmony and balance rather than affective expression between couples and between parents and children. They also showed common goals of the families to solve their problems to control the family members. The priority of the goals was getting into the higher education of their children or helping their unhealthy parents or family members. Six dimensions (affective, structural, control, cognitive, external relationship, and financial) of family functions were emerged from the ill family data. From the analysis of ill family data, types of restructuring house chore after wives illness were developed : (a) negociated, (b) accomodated, and (c) isolated, enduring types. Although the dimensions of family functioning identified in this study are similar to the conceptualizations that exist in the western literature, there were distinct differences in the nature of major themes and subconcepts under these family function dimensions.

  • PDF

Robust concurrent topology optimization of multiscale structure under load position uncertainty

  • Cai, Jinhu;Wang, Chunjie
    • Structural Engineering and Mechanics
    • /
    • 제76권4호
    • /
    • pp.529-540
    • /
    • 2020
  • Concurrent topology optimization of macrostructure and microstructure has attracted significant interest due to its high structural performance. However, most of the existing works are carried out under deterministic conditions, the obtained design may be vulnerable or even cause catastrophic failure when the load position exists uncertainty. Therefore, it is necessary to take load position uncertainty into consideration in structural design. This paper presents a computational method for robust concurrent topology optimization with consideration of load position uncertainty. The weighted sum of the mean and standard deviation of the structural compliance is defined as the objective function with constraints are imposed to both macro- and micro-scale structure volume fractions. The Bivariate Dimension Reduction method and Gauss-type quadrature (BDRGQ) are used to quantify and propagate load uncertainty to calculate the objective function. The effective properties of microstructure are evaluated by the numerical homogenization method. To release the computation burden, the decoupled sensitivity analysis method is proposed for microscale design variables. The bi-directional evolutionary structural optimization (BESO) method is used to obtain the black-and-white designs. Several 2D and 3D examples are presented to validate the effectiveness of the proposed robust concurrent topology optimization method.

프랙탈을 이용한 소자 표면의 고찰 (The Study on Surface of Devices Using Fractal.)

  • 홍경진;김창원;조재철
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2001년도 춘계학술대회 논문집 센서 박막재료
    • /
    • pp.47-51
    • /
    • 2001
  • The structural properties of varistors surface studied by fractal phenomenon were investigated to verify the relations of electrical characteristics. The SEM photograph of varistors surface were changed by binary code and the grain shape of that were analyzed by fractal dimension. The void of varistors surface was found by fractal program. The relation between grain density and electrical properties depend on fractal dimension. The grain size in varistors surface was decreased by increasing of oxide antimony addition. The grain size of devices by oxide antimony addition were from 5 to $10[{\mu}m]$. The fractal dimension and electrical properties of varistors surface was related to between grain boundary and grain density. The grain size was decreased by increasing of fractal dimensions.

  • PDF

Fractal dimension과 2차원 푸리에변환을 이용한 수질골의 특성화에 관한 실험적 연구 (Characterization of Trabecular Bone Structure using 2D Fourier Transform and Fractal Analysis)

  • 이건일
    • 치과방사선
    • /
    • 제28권2호
    • /
    • pp.339-353
    • /
    • 1998
  • The purpose of this study was to investigate whether a radiographic estimate of osseous fractal dimension and power spectrum of 2D discrete Fourier transform is useful in the characterization of structural changes in bone. Ten specimens of bone were decalcified in fresh 50 ml solutions of 0.1 N hydrochloric acid solution at cummulative timed periods of 0 and 90 minutes. and radiographed from 0 degree projection angle controlled by intraoral parelleling device. I performed one-dimensional variance. fractal analysis of bony profiles and 2D discrete Fourier transform. The results of this study indicate that variance and fractal dimension of scan line pixel intensities decreased significantly in decalcified groups but Fourier spectral analysis didn't discriminate well between control and decalcified specimens.

  • PDF

Corrosion Resistance of Stainless Steels Analyzed by Fractal Geometry

  • Kim, Eun-Ji;Park, Su-Jin;Heo, Jung-Ho;Shin, Heon-Cheol
    • Journal of Electrochemical Science and Technology
    • /
    • 제1권2호
    • /
    • pp.112-116
    • /
    • 2010
  • Fractal property of the passivated steel surface was investigated on the basis of scaling analysis with a special focus on its relationship with corrosion resistance. For this purpose, the surface of stainless steel was intentionally oxidized under a variety of passivation conditions and its scaling property was analyzed by a triangulation method. The morphology of the passivated steel surface was satisfactorily evaluated with fractal dimension. From the chronoamperometry and impedance measurement, it proved that lower fractal dimension leads to more enhanced corrosion resistance. The higher passivity of the steel surface with lower fractal dimension was discussed in terms of active area and structural imperfection.