scholarly journals Interdependence of constructive and settlement schemes of the building

2021 ◽  
pp. 17-24
Author(s):  
Volodymyr Kripak ◽  
Vira Koliakova
Keyword(s):  
Calculation Model ◽  
Design Stage ◽  
Joint Work ◽  
Rural Studies ◽  
Parking Lot ◽  
Actual Design ◽  
Peak Points ◽  
Actual Operation ◽  
Settlement Schemes ◽  
The Impact

At the design stage is very important for the formation of the reliability of any building is the stage of formation of the design model of the building, which is the basis for the construction of its load-bearing elements. The main at this stage is the adequacy of the adopted calculation model to the actual design scheme. A very important condition for assessing the actual operation of the building is to take into account the joint work of the upper part of the building (frame) with the foundations and soil base. The article examines some problems in the operation of structures, which are related to the choice of design models used in their design, on the example of a 9-storey parking lot built in the early 2000s on Pobeda Square in Kyiv. Chi-rural studies using PC LIRA-CAD analyzed the impact of joint work of the framework and foundations on the efforts at their contact. It was found that: - the impact of joint work of the frame and foundations is significant and is manifested only within a few lower floors of the frame; - taking into account the nonlinear operation of reinforced concrete structures in most cases significantly reduces the calculated forces at peak points - concentrators; - in the design process it is necessary to consider and analyze the variant design solutions of the system.

scholarly journals Model of multiple-layer pavement structure-subsoil system

2016 ◽  
Vol 64 (4) ◽  
pp. 751-762 ◽  
Author(s):  
M. Kadela
Keyword(s):  
Dimensional Space ◽  
Calculation Model ◽  
Numerical Analyses ◽  
Design Stage ◽  
3 Dimensional ◽  
Engineering Problems ◽  
Pavement Structure ◽  
System Calculation ◽  
The Impact ◽  
Made In

Abstract Progress made in recent years has brought about a high demand for increasingly modern structural and technological solutions. Each structure should in turn be designed and built to show sufficient durability for the intended period of use. The requirement of durability is met if, throughout its intended lifetime, the structure fulfils its roles regarding load-bearing capacity, serviceability limits and stability without excessive, unexpected costs. Due to the above, a need arises to predict the response of an engineering structure to given loads throughout its life. Thus it becomes increasingly common to employ numerical analyses using the finite elements method (FEM), both on the design stage and later, for the purposes of evaluating the state of a specific structure. However, a numerical calculation model may be constructed in different ways. This paper presents the impact of geometry of the model, the choice of a discretization mesh and the choice of a continuous 3D or 2D model corresponding to pavement-subgrade system calculation model. 3-dimensional modelling was carried out in this paper as full modelling of actual engineering problems in 3-dimensional space, and in the form of simplified modelling using axial symmetry. In the model, a traditional multi-layer pavement structure was considered. Criterion values obtained in numerical analyses were compared to values obtained with the use of VEROAD software.

scholarly journals A Rational Numerical Method for Simulation of Drop-Impact Dynamics of Oleo-Pneumatic Landing Gear

2021 ◽  
Vol 11 (9) ◽  
pp. 4136
Author(s):  
Rosario Pecora
Keyword(s):  
Numerical Method ◽  
Initial Conditions ◽  
Impact Load ◽  
Numerical Models ◽  
Landing Gear ◽  
Design Stage ◽  
Impact Dynamics ◽  
State Variables ◽  
Adopted Model ◽  
The Impact

Oleo-pneumatic landing gear is a complex mechanical system conceived to efficiently absorb and dissipate an aircraft’s kinetic energy at touchdown, thus reducing the impact load and acceleration transmitted to the airframe. Due to its significant influence on ground loads, this system is generally designed in parallel with the main structural components of the aircraft, such as the fuselage and wings. Robust numerical models for simulating landing gear impact dynamics are essential from the preliminary design stage in order to properly assess aircraft configuration and structural arrangements. Finite element (FE) analysis is a viable solution for supporting the design. However, regarding the oleo-pneumatic struts, FE-based simulation may become unpractical, since detailed models are required to obtain reliable results. Moreover, FE models could not be very versatile for accommodating the many design updates that usually occur at the beginning of the landing gear project or during the layout optimization process. In this work, a numerical method for simulating oleo-pneumatic landing gear drop dynamics is presented. To effectively support both the preliminary and advanced design of landing gear units, the proposed simulation approach rationally balances the level of sophistication of the adopted model with the need for accurate results. Although based on a formulation assuming only four state variables for the description of landing gear dynamics, the approach successfully accounts for all the relevant forces that arise during the drop and their influence on landing gear motion. A set of intercommunicating routines was implemented in MATLAB® environment to integrate the dynamic impact equations, starting from user-defined initial conditions and general parameters related to the geometric and structural configuration of the landing gear. The tool was then used to simulate a drop test of a reference landing gear, and the obtained results were successfully validated against available experimental data.

scholarly journals Review on Urban Heat Island in China: Methods, Its Impact on Buildings Energy Demand and Mitigation Strategies

2021 ◽  
Vol 13 (2) ◽  
pp. 762
Author(s):  
Liu Tian ◽  
Yongcai Li ◽  
Jun Lu ◽  
Jue Wang
Keyword(s):  
Energy Consumption ◽  
Urban Heat Island ◽  
Building Energy ◽  
Design Stage ◽  
Heat Island ◽  
Building Energy Consumption ◽  
Rapid Urbanization ◽  
Substantial Impact ◽  
Urban Heat ◽  
The Impact

High population density, dense high-rise buildings, and impervious pavements increase the vulnerability of cities, which aggravate the urban climate environment characterized by the urban heat island (UHI) effect. Cities in China provide unique information on the UHI phenomenon because they have experienced rapid urbanization and dramatic economic development, which have had a great influence on the climate in recent decades. This paper provides a review of recent research on the methods and impacts of UHI on building energy consumption, and the practical techniques that can be used to mitigate the adverse effects of UHI in China. The impact of UHI on building energy consumption depends largely on the local microclimate, the urban area features where the building is located, and the type and characteristics of the building. In the urban areas dominated by air conditioning, UHI could result in an approximately 10–16% increase in cooling energy consumption. Besides, the potential negative effects of UHI can be prevented from China in many ways, such as urban greening, cool material, water bodies, urban ventilation, etc. These strategies could have a substantial impact on the overall urban thermal environment if they can be used in the project design stage of urban planning and implemented on a large scale. Therefore, this study is useful to deepen the understanding of the physical mechanisms of UHI and provide practical approaches to fight the UHI for the urban planners, public health officials, and city decision-makers in China.

scholarly journals ‘I’m fine!’: Assertions of lack of support need among patients with chronic obstructive pulmonary disease: A mixed-methods study

2021 ◽  
pp. 174239532110003
Author(s):  
A Carole Gardener ◽  
Caroline Moore ◽  
Morag Farquhar ◽  
Gail Ewing ◽  
Efthalia Massou ◽  
...  
Keyword(s):  
Chronic Obstructive Pulmonary Disease ◽  
Pulmonary Disease ◽  
Mixed Method ◽  
Self Report ◽  
Design Stage ◽  
Chronic Obstructive ◽  
Support Needs ◽  
Obstructive Pulmonary Disease ◽  
Stage 1 ◽  
The Impact

Objectives To understand how people with Chronic Obstructive Pulmonary Disease (COPD) disavow their support needs and the impact on care. Methods Two stage mixed-method design. Stage 1 involved sub-analyses of data from a mixed-method population-based longitudinal study exploring the needs of patients with advanced COPD. Using adapted criteria from mental health research, we identified 21 patients who disavowed their needs from the 235 patient cohort. Qualitative interview transcripts and self-report measures were analysed to compare these patients with the remaining cohort. In stage 2 focus groups (n = 2) with primary healthcare practitioners (n = 9) explored the implications of Stage 1 findings. Results Patients who disavowed their support needs described non-compliance with symptom management and avoidance of future care planning (qualitative data). Analysis of self-report measures of mental and physical health found this group reported fewer needs than the remaining sample yet wanted more GP contact. The link between risk factors and healthcare professional involvement present in the rest of the sample was missing for these patients. Focus group data suggested practitioners found these patients challenging. Discussion This study identified patients with COPD who disavow their support needs, but who also desire more GP contact. GPs report finding these patients challenging to engage.

Grinding Force Model for Low-Speed Grinding Based on Impact Principle

2013 ◽  
Vol 797 ◽  
pp. 123-128
Author(s):  
Ming He Liu ◽  
Xiu Ming Zhang ◽  
Shi Chao Xiu
Keyword(s):  
Sliding Friction ◽  
Impact Load ◽  
Grinding Force ◽  
Calculation Model ◽  
Force Model ◽  
Grinding Process ◽  
Low Speed ◽  
Impact Area ◽  
Force Mechanism ◽  
The Impact

In the low-speed grinding process, the force generated when the wheel grinding the workpiece is the result of sliding friction, plough and cutting. While in the actual study, the cutting process has attracted extensive attention. Impact effect to the entire grinding process on the contact is ignored so that the error exists between the calculation grinding force and the measured grinding force. Basing on the shock effect to the grinding process, the paper divides the contact area into impact area and cutting area. And the model of impact load generated from single grit is built. Moreover, the grinding force theoretical calculation model and total grinding force mathematical model is also constructed by analyzing the impact load affecting on the grinding force mechanism. Finally experimental study verifies the correctness of theoretical analysis.

Research on the hydrographic survey cycle for updating navigational charts

2021 ◽  
pp. 1-13
Author(s):  
Jing Duan ◽  
Xiaoxia Wan ◽  
Jianan Luo
Keyword(s):  
Neural Network ◽  
Bp Neural Network ◽  
Calculation Model ◽  
Impact Factors ◽  
Factors Affecting ◽  
Material Resources ◽  
Hydrographic Survey ◽  
Survey Planning ◽  
The Impact ◽  
The Relationship

Abstract Due to the vast ocean area and limited human and material resources, hydrographic survey must be carried out in a selective and well-planned way. Therefore, scientific planning of hydrographic surveys to ensure the effectiveness of navigational charts has become an urgent issue to be addressed by the hydrographic office of each coastal state. In this study, a reasonable calculation model of hydrographic survey cycle is established, which can be used to make the plan of navigational chart updating. The paper takes 493 navigational charts of Chinese coastal ports and fairways as the research object, analyses the fundamental factors affecting the hydrographic survey cycle and gives them weights, proposes to use the BP neural network to construct the relationship between the cycle and the impact factors, and finally establishes a calculation model of the hydrographic survey cycle. It has been verified that the calculation cycle of the model is effective, and it can provide reference for hydrographic survey planning and chart updating, as well as suggestions for navigation safety.

A Dynamic Analysis Of The Impact Of Air Pollution On The daylight Availability In An Open-plan Office In London

2021 ◽  
pp. 94-103
Author(s):  
Jiangtao Du ◽  
Steve Sharples
Keyword(s):  
Air Pollution ◽  
Urban Areas ◽  
Simulation Analysis ◽  
Design Stage ◽  
Design Strategies ◽  
Early Design Stage ◽  
Pollutant Deposition ◽  
Open Plan ◽  
Building Project ◽  
The Impact

The deposition of air pollutants on glazing can significantly affect the daylight transmittance of building fenestration systems in urban areas. This study presents a simulation analysis of the impact of air pollution and glazing visual transmittance on indoor daylight availability in an open-plan office in London. First, the direct links between glazing visual transmittance and daylighting conditions were developed and assessed. Second, several simple algorithms were established to estimate the loss of daylight availability due to the pollutant deposition at the external surface of vertical glazing. Finally, some conclusions and design strategies to support facade planning at the early design stage of an urban building project were developed.

An investigation of the mass-market fashion design process

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Prabod Dharshana Munasinghe ◽  
D.G.K. Dissanayake ◽  
Angela Druckman
Keyword(s):  
Design Process ◽  
Market Design ◽  
High Volume ◽  
Design Stage ◽  
Fashion Design ◽  
Structured Interviews ◽  
Mass Market ◽  
Content Type ◽  
Responsible Consumption ◽  
The Impact

Purpose The process of fashion design varies between market segments, yet these variations have not yet been properly explored. This study aims to examine the fashion design process as practised at the mass-market level, as this is the most vibrant and the largest market segment in terms of production volumes and sales. Design/methodology/approach It is observed that 15 semi-structured interviews were conducted with mass-market fashion designers. Key activities of the mass-market design process were identified and a comparative analysis was conducted with the general design process. Findings The mass-market design process is found to prioritise profits rather than aesthetic aspects, with the buyer exercising more power than the designer. This hinders creativity, which, in turn, may impede a move towards more environmentally benign designs. Originality/value The clothing industry is responsible for high environmental impacts and many of these impacts arise through decisions made in the design stage. In particular, the mass-market for clothing because of its high volume of sales and fast throughput, accounts for a great deal of the impact. However, little is understood about the design process that is practised in the mass-fashion market. This paper fills the gap by developing a framework that describes the mass-market design process. Understanding the design process will enable progress to be made towards achieving the United Nations Sustainable Development Goal 12: Responsible Consumption and Production.

Evaluation of a calculation model to estimate the impact of the COVID-19 pandemic lockdown on visual acuity in neovascular AMD

2021 ◽  
pp. 112067212110523
Author(s):  
Martin Stattin ◽  
Anna-Maria Haas ◽  
Daniel Ahmed ◽  
Alexandra Graf ◽  
Katharina Krepler ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Real Life ◽  
Treatment Interruption ◽  
Term Treatment ◽  
Calculation Model ◽  
Life Outcomes ◽  
Short Term ◽  
Short Term Treatment ◽  
The Real ◽  
The Impact

Purpose A model was calculated during the first Austrian coronavirus disease-2019 (COVID-19) pandemic lockdown to estimate the effect of a short-term treatment interruption due to healthcare restrictions on visual acuity (VA) in neovascular age-related macular degeneration (nAMD). The model was compared to the real-life outcomes before treatment re-started. Methods Retrospective data-collection of 142 eyes in 142 patients receiving repeated intravitreal injections with anti-VEGF at a retina unit in Vienna in a personalized pro-re-nata regimen prior to the COVID-19 associated lockdown, when treatment was deferred between March 16 and May 4, 2020. During the lockdown, the preliminary data was integrated into pre-existing formulae based on the natural course of the disease in untreated eyes in the long term. Patients were re-scheduled and treated after gradually opening operating rooms. The calculation model was compared to the effective VA change. Results The model calculated an overall VA loss of 3.5 ± 0.8 letters early treatment diabetes retinopathy study (ETDRS) ( p < 0.001 [95% CI:3.3;3.6]) on average compared to 2.5 ± 6 letters ETDRS ( p < 0.001 [95% CI:1.5;3.5]) as measured with a mean treatment delay of 61 ± 14 days after previously scheduled appointments. The total difference between the model exercise and the real-life outcomes accounted for 1 ± 5.9 letters ETDRS ( p = 0.051 [95% CI: 0.1;1.9]). Conclusion The herein presented calculation model might not be suitable to estimate the effective VA loss correctly over time, although untreated eyes and eyes under therapy show similarities after short-term treatment interruption. However, this study demonstrated the potentially negative impact of the COVID-19 pandemic lockdown on patients compromised by nAMD.

Investigation on the Robustness of Rotor/Stator Contact Interactions with Respect to Small Mistuning

2021 ◽  
Author(s):  
Florence Nyssen ◽  
Alain Batailly
Keyword(s):  
Degrees Of Freedom ◽  
Design Stage ◽  
Contact Interactions ◽  
Reduced Basis ◽  
Amplification Factors ◽  
Bladed Disk ◽  
Nonlinear Amplification ◽  
Rotor Stator Interaction ◽  
Bending Modes ◽  
The Impact

Abstract In this work, the impact of small mistuning on rotor/stator contact interactions is investigated. First, a detailed study of a rotor/stator interaction between the first bending modes and the second engine order is presented in the tuned case. Then, a numerical investigation on the effect of mistuning on the studied rotor/stator contact interaction is carried out. In particular, a stochastic analysis is performed to evaluate the robustness of the interaction with respect to the mistuning level. Simulations are conducted using a reduced order model (ROM) of an industrial bladed disk that combines both physical degrees of freedom (along blades tip for contact treatment) and modal coordinates. Mistuning is introduced in the tuned ROM by means of a modified version of the component mode mistuning method that allows to keep physical degrees of freedom within the reduced basis. Nonlinear amplification factors, i.e. the amplification factors in the context of contact nonlinearities, are compared with their linear counterparts, the latter are computed using a linear forcing on each blade using a two nodal diameters traveling wave excitation on the mistuned and the tuned bladed disk. The comparison between the linear and nonlinear amplification factor for each sample highlights that no correlation exists between a mistuning pattern leading to high amplifications in a linear context or when contact nonlinearities are taken into account. Therefore, dedicated analyses on the effect of mistuning should be undertaken with contact nonlinearities considerations at the design stage especially if intentional mistuning is considered.

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