Frequency Window Method for Strongly Coupled and Multiply Connected Structural Systems: One-Mode Windows

1992 ◽  
Vol 59 (2S) ◽  
pp. S236-S243 ◽  
Author(s):  
Kyung-Won Min ◽  
Takeru Igusa ◽  
Jan D. Achenbach
Keyword(s):  
Iterative Procedure ◽  
Structural Systems ◽  
Structural System ◽  
Strongly Coupled ◽  
Multiply Connected ◽  
Window Method ◽  
Frequency Window ◽  
Rational Expressions ◽  
Insight Into ◽  
Reduced Problem

A method is presented to analyze the dynamic behavior of a structural system consisting of a main structure and strongly coupled, multiply connected substructures. Lagrange’s equations are used to develop a characteristic equation for connected substructures in terms of substructure impedances and mobilities. Then, a frequency window method is used to reduce the complexity of the problem by a decomposition of the impedance and mobility functions into dominant and highorder rational expressions. From the reduced problem, simple expressions for the modal properties are developed using matrix algebraic methods, which provide insight into the resonance characteristics of the connected substructures. Higherorder terms, which become significant for strongly coupled substructures, are included in the eigenvalue analysis by using an iterative procedure. It is shown that the frequency window method developed in this paper, used as a numerical scheme, produces results which converge to exact results after only a few iterations.

Frequency Window Method for Strongly Coupled and Multiply Connected Structural Systems: Multiple-Mode Windows

1992 ◽  
Vol 59 (2S) ◽  
pp. S244-S252 ◽  
Author(s):  
K.-W. Min ◽  
T. Igusa ◽  
J. D. Achenbach
Keyword(s):  
Companion Paper ◽  
Structural System ◽  
Strongly Coupled ◽  
Multiply Connected ◽  
Multiple Mode ◽  
Window Method ◽  
Frequency Window ◽  
Rational Expressions ◽  
Insight Into ◽  
Reduced Problem

In a companion paper, a method is presented to analyze the dynamic behavior of a structural system consisting of a main structure and strongly coupled, multiply connected substructures. Lagrange’s equations are used to develop a characteristic equation for connected substructures in terms of substructure impedances and mobilities. A frequency window method is used to reduce the complexity of the problem by a decomposition of the impedance and mobility functions into dominant and higher-order rational expressions. From the reduced problem, simple expressions for the modal properties are developed using matrix algebraic methods, which provide insight into the resonance characteristics of the connected substructures. Onemode windows were discussed in detail and examples were presented. In the present paper the theory is extended to multiple-mode windows.

COMPREHENSIVE REFORMING OF TECHNOLOGICAL, FUNCTIONAL AND STRUCTURAL SYSTEMS OF SKIN UNITS OF HOSPITALS

2020 ◽  
pp. 211-218
Author(s):  
Владимир Григорьевич Донцов ◽  
Елена Владимировна Донцова ◽  
Любовь Анатольевна Новикова ◽  
Лариса Николаевна Борзунова
Keyword(s):  
Service System ◽  
Medical Examination ◽  
Structural Systems ◽  
Structural System ◽  
Structural Units

В статье доказана порочность переустройства только одной структурной системы (реструктуризации), так как это чревато поломками элементов, звеньев и блоков, сомой системы кожной службы. Допустимо лишь незначительная адаптация к конкретным условиям больниц, где это будет внедряться. Сформулированы понятия конечного результата работы врачей и структурных подразделений медицинских стационаров в современных условиях общественно-политической формации. Описаны преимущества реконструкции комплекса систем судебно-медицинской экспертизы как экспериментальной службы для кожного отделения городской многопрофильной больницы и работы самого кожного отделения. Описана форма структурного построения судебно-медицинской и кожной служб. По аналоги с экспертным учреждением ожидаются аналогичные изменение конечного результата в кожном подразделении многопрофильного стационара The article proves the viciousness of the reorganization of only one structural system (restructuring), since this is fraught with breakdowns of elements, links and blocks, the soma of the skin service system. Only slight adaptation to the specific conditions of the hospitals where it will be implemented is acceptable. The concepts of the final result of the work of doctors and structural units of medical hospitals in the modern conditions of the socio-political formation are formulated. The advantages of reconstruction of a complex of forensic medical examination systems as an experimental service for the skin department of a city multidisciplinary hospital and the work of the skin department itself are described. The form of structural structure of forensic and skin services is described. By analogy with an expert institution, a similar change in the final result is expected in the skin department of a multidisciplinary hospital

scholarly journals Parametric Analysis of the Shear Lag Effect in Tube Structural Systems of Tall Buildings

2020 ◽  
Vol 11 (1) ◽  
pp. 278
Author(s):  
Ivan Hafner ◽  
Anđelko Vlašić ◽  
Tomislav Kišiček ◽  
Tvrtko Renić
Keyword(s):  
Parametric Analysis ◽  
Numerical Models ◽  
Tall Buildings ◽  
Structural Systems ◽  
Structural Elements ◽  
Structural System ◽  
Shear Lag ◽  
Shear Lag Effect ◽  
Lag Effect ◽  
Secondary Structural Elements

Horizontal loads such as earthquake and wind are considered dominant loads for the design of tall buildings. One of the most efficient structural systems in this regard is the tube structural system. Even though such systems have a high resistance when it comes to horizontal loads, the shear lag effect that is characterized by an incomplete and uneven activation of vertical elements may cause a series of problems such as the deformation of internal panels and secondary structural elements, which cumulatively grow with the height of the building. In this paper, the shear lag effect in a typical tube structure will be observed and analyzed on a series of different numerical models. A parametric analysis will be conducted with a great number of variations in the structural elements and building layout, for the purpose of giving recommendations for an optimal design of a tube structural system.

Effects of the SNAP25 on Integration Ability of Brain Functions in Children With ADHD

2020 ◽  
pp. 108705472096456
Author(s):  
Yue Yang ◽  
Gang Peng ◽  
Hongwu Zeng ◽  
Diangang Fang ◽  
Linlin Zhang ◽  
...  
Keyword(s):  
Time Window ◽  
Precentral Gyrus ◽  
Children With Adhd ◽  
Brain Functions ◽  
Lingual Gyrus ◽  
Window Method ◽  
Central Gyrus ◽  
The Right ◽  
The Brain ◽  
Insight Into

Objective: The present study aimed to examine the effects of SNAP25 on the integration ability of intrinsic brain functions in children with ADHD, and whether the integration ability was associated with working memory (WM). Methods: A sliding time window method was used to calculate the spatial and temporal concordance among five rs-fMRI regional indices in 55 children with ADHD and 20 healthy controls. Results: The SNAP25 exhibited significant interaction effects with ADHD diagnosis on the voxel-wise concordance in the right posterior central gyrus, fusiform gyrus and lingual gyrus. Specifically, for children with ADHD, G-carriers showed increased voxel-wise concordance in comparison to TT homozygotes in the right precentral gyrus, superior frontal gyrus, postcentral gyrus, and middle frontal gyrus. The voxel-wise concordance was also found to be related to WM. Conclusion: Our findings provided a new insight into the neural mechanisms of the brain function of ADHD children.

scholarly journals Modeling and Experimental Validation of the VARTM Process for Thin-Walled Preforms

Polymers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 2003
Author(s):  
Da Wu ◽  
Ragnar Larsson ◽  
Mohammad S. Rouhi
Keyword(s):  
Shell Model ◽  
Computational Efficiency ◽  
Large Scale ◽  
Strongly Coupled ◽  
Thin Walled Structures ◽  
Simulation Based ◽  
Thin Walled ◽  
High Computational Efficiency ◽  
Insight Into ◽  
Vartm Process

In this paper, recent shell model is advanced towards the calibration and validation of the Vacuum-assisted Resin Transfer Molding (VARTM) process in a novel way. The model solves the nonlinear and strongly coupled resin flow and preform deformation when the 3-D flow and stress problem is simplified to a corresponding 2-D problem. In this way, the computational efficiency is enhanced dramatically, which allows for simulations of the VARTM process of large scale thin-walled structures. The main novelty is that the assumptions of the neglected through-thickness flow and the restricted preform deformation along the normal of preform surface suffice well for the thin-walled VARTM process. The model shows excellent agreement with the VARTM process experiment. With good accuracy and high computational efficiency, the shell model provides an insight into the simulation-based optimization of the VARTM process. It can be applied to either determine locations of the gate and vents or optimize process parameters to reduce the deformation.

Damage Identification in Collocated Structural Systems Using Structural Markov Parameters

2013 ◽  
Author(s):  
Ramin Bighamian ◽  
Hamid Reza Mirdamadi ◽  
Jin-Oh Hahn
Keyword(s):  
Structural Damage ◽  
Damage Identification ◽  
Mode Shapes ◽  
Structural Systems ◽  
Structural System ◽  
Computationally Efficient ◽  
Markov Parameters ◽  
Novel Approach ◽  
Stiffness Matrices ◽  
Stiffness Characteristics

This paper presents a novel approach to damage identification in a class of collocated multi-input multi-output structural systems. In the proposed approach, damage is identified via the structural Markov parameters obtained from a system identification procedure, which is in turn exploited to localize and quantify damage by evaluating relative changes occurring in the mass and stiffness matrices associated with the structural system. To this aim, an explicit relationship between structural Markov parameters versus mass and stiffness matrices is developed. The main strengths of the proposed approach are that it is capable of quantitatively identifying the occurrence of multiple damages associated with both mass and stiffness characteristics in the structural system, and it is computationally efficient in that it is solely based on the structural Markov parameters but does not necessitate costly calculations related to natural frequencies and mode shapes, making it highly attractive for structural damage detection and health monitoring applications. Numerical examples are provided to demonstrate the validity and effectiveness of the proposed approach.

scholarly journals Methodology to Evaluate the Embodied Primary Energy and CO2 Production at Each Stage of the Life Cycle of Prefabricated Structural Systems: The Case of the Solar Decathlon Competition

Energies ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 4311
Author(s):  
J.F. Luna-Tintos ◽  
Carlos Cobreros ◽  
Álvaro López-Escamilla ◽  
Rafael Herrera-Limones ◽  
Miguel Torres-García
Keyword(s):  
Life Cycle ◽  
Construction Industry ◽  
Primary Energy ◽  
Co2 Production ◽  
Structural Systems ◽  
Structural System ◽  
Audit Tool ◽  
Solar Decathlon ◽  
Environmental Demand ◽  
Emission Of Greenhouse Gases

The construction industry is responsible for a high percentage of the energy consumed on the planet and the emission of greenhouse gases, therefore it is considered necessary to rethink many of the processes that this industry carries out in order to reduce its environmental impact. For this, one of the paths could take into account the Life Cycle Assessment of the used materials, for which it is necessary to evaluate this aspect through indicators that allow the qualification and quantification of the weight of these environmental impacts. In this context, this article presents a methodological proposal for the quantitative evaluation of the embodied primary energy and CO2 production at each stage of the life cycle of prefabricated structural systems, taking as case studies eight prototypes from the “Solar Decathlon” competition in its editions of Europe (2014), United States (2015) and Latin America (2015), through a Simplified Life Cycle Analysis, using the Eco Audit tool from CES Edupack. Through this analysis, conclusions are drawn about the optimization of a structural system with lower environmental demand and the possibilities of transferring knowledge from this competition to be applied in innovative systems of new housing models.

Approach to Steel-Bamboo Composite Structure System

2013 ◽  
Vol 300-301 ◽  
pp. 1263-1266 ◽  
Author(s):  
Zhi Min Yan ◽  
Yong Fei Du ◽  
Jun Guo Huang ◽  
Yu Shun Li
Keyword(s):  
Energy Saving ◽  
High Strength ◽  
Structural Systems ◽  
Structural Elements ◽  
Structural System ◽  
Sustainable Building ◽  
Production Methods ◽  
Building Technology ◽  
Earthquake Resistant ◽  
New Type

Modern bamboo structural system is a new type of green sustainable building technology, conform with our country’s requirements of developing environment-protecting and energy-saving buildings. This paper presents a new lightweight, high-strength , earthquake-resistant and energy-saving system-steel-bamboo composite structural systems , and given the various structural elements of the composite structural systems of steel-bamboo production methods . This paper also gives the production methods of steel-bamboo composite elements. Steel-bamboo-structural system can per-fectly combine steel and bamboo to bear load together, and it have excellent mechanical properties and broad application prospects.

Examples of Shaping for Large Span Roofs and High-Rise Buildings

1996 ◽  
Vol 11 (1-2) ◽  
pp. 241-250
Author(s):  
Janusz Rebielak
Keyword(s):  
Tall Building ◽  
Space Structures ◽  
Structural Systems ◽  
Building Structures ◽  
Structural System ◽  
Large Span ◽  
High Rise ◽  
Slender Structure

Proposals for forming various types of bar space structures, which could be used as building structures of different functional purposes are the subjects of this paper. The systems proposed have been developed with the aim of applying them in the design of structural systems for large span covers and high-rise buildings. The essential aims of forming large span cover structures is to obtain systems which would allow building these covers using relatively short bars. In the paper some new configuations of such space structures are presented. The most important factor in the design of the structural system of a tall building is the need to provide a comparatively slender structure with appropriate great rigidity. Some proposals of application of space structures as structures of high-rise buildings are presented in the paper.

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