• 복합신소재구조학회 논문집
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• 제5권4호
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• pp.36-43
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• 2014

In this study, circular sectional concrete-filled tube(CFT) column-to-foundation connections were numerically investigated in order to improve their structural details. A inner reinforced specimen with high-tension bolts and inner deformed bars was adopted from a previous experimental study to make the numerical model. The validity of the numerical method was verified through comparing the experimental results with the analysis's ones. In order to optimize design variables about the inner reinforced model, a number of numerical analyses were conducted for various variables. Finally, this study suggested the optimum variables about the reinforced circular sectional CFT column-to-foundation connections.

• 건축역사연구
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• 제23권4호
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• pp.91-100
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• 2014

There are lots of and kinds of stone pagoda and stone Buddhas at Unjusa Temple in Hwasun, Jeonnam, which is thus called as Cheontap(千塔) or Cheonbul.(千佛) Several archaeological excavations have been conducted in Unjusa though, the foundation purpose or background motivation is yet wrapped in mystery. Circular shape is representative pagoda of Unjusa made of round frame or spherical roof but circular stone pagoda is unusual that there is no similar example found in India or China as well as in Korea. Located in the symbolic center, Circular stone pagoda is a key to understand Unjusa. Yundeung(輪燈) is made of stone for circular stone pagoda and there are craft lamp and large lamp. The large lamp, for the palace courtyard on the occasion of Palgwanhoe,(八關會) consists of discs and light on each disc. Outdoor lamp of circular stone pagoda made of stone for permanent preservation purpose. Unjusa is a very special temple with stone-yundeung for circular stone pagoda. In this study, a circular stone pagoda that is the source of yundeung said. Unjusa circular stone pagoda next to the title of 'yundeung pagoda' and proposes to call.

• Archives of Plastic Surgery
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• 제41권5호
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• pp.500-504
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• 2014

Background Skin cancer is the most prevalent cancer by organ type and referral accuracy is vital for diagnosis and management. The British Association of Dermatologists (BAD) and literature highlight the importance of accurate skin lesion examination, diagnosis and educationally-relevant studies. Methods We undertook a review of the relevant literature, a national audit of skin lesion description standards and a study of speciality training influences on these descriptions. Questionnaires (n=200), with pictures of a circular and an oval lesion, were distributed to UK dermatology/plastic surgery consultants and speciality trainees (ST), general practitioners (GP), and medical students (MS). The following variables were analysed against a pre-defined 95% inclusion accuracy standard: site, shape, size, skin/colour, and presence of associated scars. Results There were 250 lesion descriptions provided by 125 consultants, STs, GPs, and MSs. Inclusion accuracy was greatest for consultants over STs (80% vs. 68%; P<0.001), GPs (57%) and MSs (46%) (P<0.0001), for STs over GPs (P<0.010) and MSs (P<0.0001) and for GPs over MSs (P<0.010), all falling below audit standard. Size description accuracy sub-analysis according to circular/oval dimensions was as follows: consultants (94%), GPs (80%), STs (73%), MSs (37%), with the most common error implying a quadrilateral shape (66%). Addressing BAD guidelines and published requirements for more empirical performance data to improve teaching methods, we performed a national audit and studied skin lesion descriptions. To improve diagnostic and referral accuracy for patients, healthcare professionals must strive towards accuracy (a circle is not a square). Conclusions We provide supportive evidence that increased speciality training improves this process and propose that greater focus is placed on such training early on during medical training, and maintained throughout clinical practice.

• Structural Engineering and Mechanics
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• 제65권5호
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• pp.505-511
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• 2018

Recently, a new foundation model called "Dynamic foundation model" was proposed for the dynamic analysis of structures on the foundation. This model includes a linear elastic spring, shear layer, viscous damping and the special effects of mass density parameter of foundation during vibration. However, the relationship of foundation property parameters with the experimental parameter of the influence of foundation mass also has not been established in previous research. Hence, the purpose of the paper presents a simple experimental model in order to establish relationships between foundation properties such as stiffness, depth of foundation and experimental parameter of the influence of foundation mass. The simple experimental model is described by a steel plate connected with solid rubber layer as a single degree of freedom system including an elastic spring connected with lumped mass. Based on natural circular frequencies of the experimental models determined from FFT analysis plots of the time history of acceleration data, the experimental parameter of the influence of foundation mass is obtained and the above relationships are also discussed.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.692-697
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• 2010

In this paper, a design program for electric railway pole foundation was developed by applying the estimation study performed by Korean Railway. There are two kinds of shapes in the cross-section of electric railway pole foundation: rectangle and circle. In foundation designing, The rectangular foundation should be satisfied with vertical, horizontal and moment equilibrium equations. On the other hand, the circular foundation should be satisfied with horizontal and moment equilibrium equations. The design program was coded into MFC(Microsoft Foundation Class) by MS Visual C. The equation's roots in the program were obtained by Incremental Search method. Dialog and property sheet(Wizard Mode) input windows were selected for user-friendliness. The biggest advantage of this program is to find an optimum depth in a given section.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2005년도 학술발표회 논문집
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• pp.47-51
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• 2005

If a structure is founded on the ground saturated with pore water, then the ground should be modeled as a saturated two-phase porous medium for accurate earthquake response analysis. In this study, an axisymmetric transmitting boundary hyperelement is developed for modeling of far field of the ground using u-U formulation for water-saturated transversely isotropic layered stratum. The developed hyperelement is verified by comparing the dynamic stiffness of rigid circular foundation on water-saturated isotropic layered stratum with the case of using equivalent single-phase medium model.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.898-901
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• 2004

Since soil-structure interactions are one of the most important subjects in the structural/foundation engineering, much study concerning the soil-structure interactions had been carried out. One of typical structures related to the soil-structure interactions is the strip foundation which is basically defined as the beam or strip rested on or supported by the soils. At the present time, lack of studies on dynamic problems related to the strip foundations is still found in the literature. From these viewpoint, this paper aims to theoretically investigate dynamics of the circular strip foundations and also to present the practical engineering data for the design purpose. Differential equations governing the free, out-of-plane vibrations of such strip foundations are derived, in which effects of the rotatory and torsional inertias and also shear deformation are included although the warping of the cross-section is excluded. Governing differential equations subjected to the boundary conditions of corresponding end constraints are numerically solved for obtaining the natural frequencies and mode shapes by using the numerical integration technique and the numerical method of non-linear equation.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 춘계학술대회논문집
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• pp.788-793
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• 2004

The main purpose of this paper is to Investigate the free vibrations of circular curved members resting on nonhomogeneous elastic foundations. The governing differential equations derived in a previous paper are used. The governing equations are solved numerically to obtain frequencies. Hinged-hinged end constraint is considered in numerical examples. The lowest three natural frequencies are calculated over a wide range of non-dimensional system parameters: the foundation rested ratio, the foundation parameter, the horizontal rise to span length ratio, the slenderness ratio, and the width ratio of the contact area between the member and the foundation.

• Structural Engineering and Mechanics
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• 제40권2호
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• pp.279-295
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• 2011

A solution of space curved bars with generalized Winkler soil found by means of Transfer Matrix Method is presented. Distributed, concentrated loads and imposed strains are applied to the beam as well as rigid or elastic boundaries are considered at the ends. The proposed approach gives the analytical and numerical exact solution for circular beams and rings, loaded in the plane or perpendicular to it. A well-approximated solution can be found for general space curved bars with complex geometry. Elastic foundation is characterized by six parameters of stiffness in different directions: three for rectilinear springs and three for rotational springs. The beam has axial, shear, bending and torsional stiffness. Numerical examples are given in order to solve practical cases of straight and curved foundations. The presented method can be applied to a wide range of problems, including the study of tanks, shells and complex foundation systems. The particular case of box girder distortion can also be studied through the beam on elastic foundation (BEF) analogy.

• Coupled systems mechanics
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• 제5권3호
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• pp.255-267
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• 2016

To investigate the surface effects on vibration of embedded circular curved nanosize beams, nonlocal elasticity model is used in combination with surface properties including surface elasticity, surface tension and surface density for modeling the nano scale effect. The governing equations are determined via the energy method. Analytically Navier method is utilized to solve the governing equations for simply supported at both ends. Solving these equations enables us to estimate the natural frequency for circular curved nanobeam including Winkler and Pasternak elastic foundations. The results determined are verified by comparing the results by available ones in literature. The effects of various parameters such as nonlocal parameter, surface properties, Winkler and Pasternak elastic foundations and opening angle of circular curved nanobeam on the natural frequency are successfully studied. The results reveal that the natural frequency of circular curved nanobeam is significantly influenced by these effects.