• Title/Summary/Keyword: Structural features

Search Result 1,430, Processing Time 0.026 seconds

Ambient vibration tests of XV century Renaissance Palace after 2012 Emilia earthquake in Northern Italy

  • Cimellaro, Gian Paolo;De Stefano, Alessandro
    • Structural Monitoring and Maintenance
    • /
    • v.1 no.2
    • /
    • pp.231-247
    • /
    • 2014
  • This paper focuses on the dynamic behaviour of Mirandola City Hall (a XV century Renaissance Palace) that was severely damaged during May 2012 Emilia earthquake in Northern Italy. Experimental investigations have been carried out on this monumental building. Firstly, detailed investigations have been carried out to identify the identification of the geometry of the main constructional parts as well as the mechanical features of the constituting materials of the palace. Then, Ambient Vibration Tests (AVT) have been applied, for the detection of the main dynamic features. Three output-only identification methods have been compared: (i) the Frequency Domain Decomposition, (ii) the Random Decrement (RD) and the (iii) Eigensystem Realization Algorithm (ERA). The modal parameters of the Palace were difficult to be identified due to the severe structural damage; however the two bending modes in the perpendicular directions were identified. The comparison of the three experimental techniques showed a good agreement confirming the reliability of the three identification methods.

Structural Characteristic Analysis of an Ultra-Precision Machine for Machining Large-Surface Micro-Features (초정밀 대면적 미세 형상 가공기의 구조 특성 해석)

  • Kim, Seok-ll;Lee, Won-Jae
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.31 no.12
    • /
    • pp.1173-1179
    • /
    • 2007
  • In recent years, research to machine large-surface micro-features has become important because of the light guide panel of a large-scale liquid crystal display and the bipolar plate of a high-capacity proton exchange membrane fuel cell. In this study, in order to realize the systematic design technology and performance improvements of an ultra-precision machine for machining the large-surface micro-features, a structural characteristic analysis was performed using its virtual prototype. The prototype consisted of gantry-type frame, hydrostatic feed mechanisms, linear motors, brushless DC servo motor, counterbalance mechanism, and so on. The loop stiffness was estimated from the relative displacement between the tool post and C-axis table, which was caused by a cutting force. Especially, the causes of structural stiffness deterioration were identified through the structural deformation analysis of sub-models.

Luminosity Distribution of Dwarf Elliptical-like Galaxies

  • Seo, Mira;Ann, Hong Bae
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.43 no.1
    • /
    • pp.32.2-32.2
    • /
    • 2018
  • We present the structural parameters of ~ 910 dwarf elliptical-like galaxies in the local universe ($z{\lesssim}0.01$) derived from the r-band images of the Sloan Digital SKy Survey (SDSS). We examine the dependence of structural parameters on the morphological types (dS0, dE, dEbc, dSph, and dEblue) and the environment. There is not much difference in the structural parameters among the five subtypes but the mean surface brightness within the effective radius (<${\mu}e$>) of dSph galaxies is clearly different from that of other subtypes. The frequency of disk features such as spiral arm, bar, lens, and rings strongly depends on the morphology of dwarf elliptical-like galaxies with no disk features in dSph galaxies. The absence of disk features and the low surface brightness of dSph galaxies are thought to be closely related to their low mass which leads to different evolution from other subtypes of dwarf elliptical-like galaxies. Density Environments Using IMSNG.

  • PDF

Color-Image Guided Depth Map Super-Resolution Based on Iterative Depth Feature Enhancement

  • Lijun Zhao;Ke Wang;Jinjing, Zhang;Jialong Zhang;Anhong Wang
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.17 no.8
    • /
    • pp.2068-2082
    • /
    • 2023
  • With the rapid development of deep learning, Depth Map Super-Resolution (DMSR) method has achieved more advanced performances. However, when the upsampling rate is very large, it is difficult to capture the structural consistency between color features and depth features by these DMSR methods. Therefore, we propose a color-image guided DMSR method based on iterative depth feature enhancement. Considering the feature difference between high-quality color features and low-quality depth features, we propose to decompose the depth features into High-Frequency (HF) and Low-Frequency (LF) components. Due to structural homogeneity of depth HF components and HF color features, only HF color features are used to enhance the depth HF features without using the LF color features. Before the HF and LF depth feature decomposition, the LF component of the previous depth decomposition and the updated HF component are combined together. After decomposing and reorganizing recursively-updated features, we combine all the depth LF features with the final updated depth HF features to obtain the enhanced-depth features. Next, the enhanced-depth features are input into the multistage depth map fusion reconstruction block, in which the cross enhancement module is introduced into the reconstruction block to fully mine the spatial correlation of depth map by interleaving various features between different convolution groups. Experimental results can show that the two objective assessments of root mean square error and mean absolute deviation of the proposed method are superior to those of many latest DMSR methods.

Damage Monitoring of PSC Girder Bridges based on Acceleration -Impedance Signals under Uncertain Temperature Conditions (불확실한 온도 조건하의 PSC 거더 교량의 가속도-임피던스기반 손상 모니터링)

  • Hong, Dong-Soo;Kim, Jeong-Tae
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.24 no.1
    • /
    • pp.107-117
    • /
    • 2011
  • In this study, the effect of temperature-induced uncertainty to damage monitoring using acceleration-impedance response features is analyzed for presterssed concrete(PSC) girder bridges. Firstly, a damage monitoring algorithm using global and local vibration features is designed. As global and local features, acceleration and electro-mechanical impedance features are selected respectively. Secondly, the temperature effect on the acceleration and impedance features for a lab-scaled PSC girder is experimentally analyzed. From the experimental results, compensation models for temperature-acceleration features and temperature-impedance features are estimated. Finally, the feasibility of the acceleration-impedance-based damage monitoring technique using the compensation model is evaluated in the PSC girder for which a set of prestress-loss and flexural stiffness loss cases were dynamically tested.

Development and Application of Metropolis Genetic Algorithm for the Structural Design Optimization (구조물의 설계 최적화를 위한 메트로폴리스 유전알고리즘의 개발 및 적용)

  • 박균빈;류연선;김정태;조현만
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 2003.10a
    • /
    • pp.115-122
    • /
    • 2003
  • A Metropolis genetic algorithm(MGA) is developed and applied for the structural design optimization. In MGA favorable features of Metropolis algorithm in simulated annealing(SA) are incorporated in simple genetic algorithm(SGA), so that the MGA alleviates the disadvantage of finding imprecise solution in SGA and time-consuming computation in SA. Performances of MGA are compared with those of conventional algorithms such as Holland's SGA, Krishnakumar's micro genetic algorithm(μGA), and Kirkpatrick's SA. Typical numerical examples are used to evaluate the favorable features and applicability of MGA From the theoretical evaluation and numerical experience, it is concluded that the proposed MGA is a reliable and efficient tool for structural design optimization.

  • PDF

Creation of Soccer Video Highlight Using The Structural Features of Caption (자막의 구조적 특징을 이용한 축구 비디오 하이라이트 생성)

  • Huh, Moon-Haeng;Shin, Seong-Yoon;Lee, Yang-Weon;Ryu, Keun-Ho
    • The KIPS Transactions:PartD
    • /
    • v.10D no.4
    • /
    • pp.671-678
    • /
    • 2003
  • A digital video is usually very long temporally. requiring large storage capacity. Therefore, users want to watch pre-summarized video before they watch a large long video. Especially in the field of sports video, they want to watch a highlight video. Consequently, highlight video is used that the viewers decide whether it is valuable for them to watch the video or not. This paper proposes how to create soccer video highlight using the structural features of the caption such as temporal and spatial features. Caption frame intervals and caption key frames are extracted by using those structural features. And then, highlight video is created by using scene relocation, logical indexing and highlight creation rule. Finally. retrieval and browsing of highlight and video segment is performed by selection of item on browser.

Application of a modified structural clay model considering anisotropy to embankment behavior

  • Zhang, Hao;Chen, Qiushi;Chen, Jinjian;Wang, Jianhua
    • Geomechanics and Engineering
    • /
    • v.13 no.1
    • /
    • pp.79-97
    • /
    • 2017
  • Natural clays exhibit features such as structural and anisotropy. In this work, a constitutive model that is able to replicate these two salient features of natural clays is presented. The proposed model is based on the classical S-CLAY1 model, where the anisotropy of the soil is captured through the initial inclination and rotation of the yield surface. To account for the structural of the soil, the compression curve of the reconstituted soil is taken as the reference. All parameters of the proposed constitutive model have clear physical meanings and can be conveniently determined from conventional triaxial tests. This proposed model has been used to simulate the behavior of soft soil in the undrained triaxial tests and the performance of Murro embankment in terms of settlement and horizontal displacements during embankment construction and consolidation stage. Results of numerical simulations using proposed model have been compared with the field measurement data. The comparisons show that the two features significantly influence the prediction results.

An Analysis on Structural Knowledges by Concept Maps -Focused on Plane Figures in Elementary School- (개념도를 이용한 구조적 지식의 조사 연구 -초등학교 평면 도형 단원을 중심으로-)

  • 정승진;박배훈
    • Education of Primary School Mathematics
    • /
    • v.2 no.1
    • /
    • pp.65-73
    • /
    • 1998
  • The purpose of this study is to investigate significant differences of structural knowledges among the groups(high, middle, low) when the 6th grade subjects structured the concepts of the plane figures, triangle and quadrangle, by concept maps, and to analyse the features of concept maps according to hierarchy. For this purpose, the following two research contents were investigated: 1. Investigating significant differences of structural knowledge in the concepts of the plane figures using concept maps among the groups(high, middle, low). 2. Analysing the features of concept maps according to hierarchy. The structural knowledges represented on the concept maps of triangle and quadrangle which were drawn by the subjects were analysed by propositions, hierarchies, and cross-links. Subject-self Reports about how to make the concept maps were used to analyse the features of concept maps according to hierarchy. The conclusions drawn from the results were as fellows: First, there were significant differences among the groups in proposition links. Second, there wasn't my significant difference among the groups in hierarchy. Third, there were significant differences among the groups in cross-links, and Fourth, the results of analysing the concept maps by hierarchy showed that there were differences among the individuals in constructing the knowledges.

  • PDF

Relationships between Structural Features and Biological Activities of HC-toxin

  • Kim, Shin-Duk
    • BMB Reports
    • /
    • v.28 no.3
    • /
    • pp.227-231
    • /
    • 1995
  • In order to figure out the relationships between structural features and biological activity of the host-specific HC-toxin in maize, structurally related cyclic tetrapeptides, chlamydocin and CYL-2 were isolated, and their biological activities in maize were examined. Biological activities of preparations were determined by root growth inhibition and electrolyte leakage bioassays. Chlamydocin and CYL-2 showed toxicities to maize. However, the toxicities of these compounds were non-specific. Thus, the precise peptide ring structure of HC-toxin apparently does not play an important role in toxicity, while resistance of maize to HC-toxin is based on a precise ring conformation.

  • PDF