scholarly journals A Study on the Mechanism of Impact between Curved Bridge Segments Using Nonsmooth Dynamics

2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Wenshan Li ◽  
Yong Huang ◽  
Guangming Xie
Keyword(s):  
Contact Point ◽  
Single Point ◽  
Nonsmooth Dynamics ◽  
Curved Bridges ◽  
Curved Bridge ◽  
Coulomb’S Friction ◽  
The Coefficient Of Friction ◽  
Mechanism Of Impact ◽  
The Impact ◽  
Impacts With Friction

It has been observed in many previous earthquakes that impact often occurs between the main girders in curved bridges. An earthquake can result in deck-unseating leading to catastrophic destruction of the structure. In this paper, the nonsmooth multirigid body dynamics method and the set-valued formulation were used to model and analyze the mechanism of impact between the curved bridge segments. The analysis demonstrated that these impacts are the major cause of segment rotation. The main contribution of this paper is to use Newton’s impact law and Coulomb’s friction law to describe the interaction between the curved bridge segments in the form of a set-valued function and to express impacts with friction as a linear complementary problem. For frictionless and frictional contact, the paper considers the single-point and multipoint impacts using the linear complementary formula to detect the unique actual slip-stick conditions of these states. A variety of criteria for distinguishing each case are presented and the results provide the kinetic characteristics of each contact case. The analysis has shown that the impact between the segments of a curved bridge and the tendency of the segments to rotate (and thus detach) are related to the overall geometry, the coefficient of restitution, the coefficient of friction, and the preimpact conditions in the plane of motion. Finally, a theoretical relationship diagram of the impact, rotation slip, and stick condition of the curved bridge segments at the contact point is given. The presented results will be useful for the seismic design of curved bridges.

scholarly journals Eccentricity-Induced Seismic Behavior of Curved Bridges Based on Controllability

Symmetry ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 1633
Author(s):  
Yumei Wang
Keyword(s):  
Seismic Behavior ◽  
Center Of Mass ◽  
Time History ◽  
Singular Values ◽  
Curved Bridges ◽  
Curved Bridge ◽  
Moment Arms ◽  
Design Time ◽  
Hankel Singular Values ◽  
The Impact

The difficulty in curved bridge design lies in the eccentricity. Eccentricities break the regularity and make it difficult to resist horizontal loads. However, relatively stable and robust performance can still be achieved through properly aligned eccentricity. This paper used the controllability-related concepts, the controllability Grammians and Hankel singular values (HSVs), to study the impact of eccentricities on the seismic performance of curved bridges. An analytical model was expressed by second order differential equations with rigid deck assumption. Six eccentricity cases: three different radii (resulting in different center of mass (CM)), three different bearing arrangements (resulting in different center of stiffness (CS)), and variable earthquake directions (resulting in different moment arms) were strategized for research. Analyses showed that effects of eccentricities (offsets of CS from CM) can be extensively interpreted by controllability indices. Proper eccentricity may “reach” and thus “control” the responses better and decrease the coupling effects, counteract the unfavorable excitation effects, and make the bridge less sensitive to excitation changes. In this sense, regularity or stability could be somewhat re-established through design. Time history analyses confirmed the results.

scholarly journals OP0277-PARE METABERN, THE EUROPEAN REFERENCE NETWORK FOR RARE HEREDITARY DISEASES: STRUCTURE, OBJECTIVES, METABOLIC RMDS AND THE ROLES OF EUROPEAN PATIENT ADVOCACY GROUPS (EPAGS)

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 168.2-168
Author(s):  
L. Wagner ◽  
S. Sestini ◽  
C. Brown ◽  
A. Finglas ◽  
R. Francisco ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Health Care ◽  
Social Science ◽  
Metabolic Pathways ◽  
Metabolic Disorders ◽  
Clinical Care ◽  
Single Point ◽  
Link Type ◽  
The Impact

Background:Inborn metabolic disorders (IMDs) currently encompass more than 1,500 diseases with new ones still to be identified1. Each of them is characterised by a genetic defect affecting a metabolic pathway. Only few of them have curative treatments, that target the respective metabolic pathway. Commonly, treatment examples include diet, substrate reduction therapies, enzyme replacement therapies, gene therapy and biologicals, enabling IMD-patient now to survive to adulthood. About 30 % of all IMDs involve the musculoskeletal system and are here referred to as rare metabolic RMDs. Generally, IMDs are very heterogenous with respect to symptoms and severity, often being systemic and affecting more children than adults. Thus, challenges include certified advanced training of adult metabolic experts, standardised transition plans, social support and development of therapies for diseases that do not have any cure yet.Objectives:Introduction of MetabERN, its structure and objectives, highlighting on the unique features and challenges of metabolic RMDs and describing the involvement of patient representation in MetabERN.Methods:MetabERN is stratified in 7 subnetworks (SNW) according to the respective metabolic pathways and 9 work packages (WP), including administration, dissemination, guidelines, virtual counselling framework, research/clinical trials, continuity of care, education and patient involvement. The patient board involves a steering committee and single point of contacts for each subnetwork and work package, respectively2. Projects include identifying the need of implementing social science to assess the psycho-socio-economic burden of IMDs, webinars on IMDs and their transition as well as surveys on the impact of COVID-193 on IMD-patients and health care providers (HCPs), social assistance for IMD-patients and analysing the transition landscape within Europe.Results:The MetabERN structure enables bundling of expertise, capacity building and knowledge transfer for faster diagnosis and better health care. Rare metabolic RMDs are present in all SNWs that require unique treatments according to their metabolic pathways. Implementation of social science to assess the psycho-socio-economic burden of IMDs is still underused. Involvement of patient representatives is essential for a holistic healthcare not only focusing on clinical care, but also on the quality of life for IMD-patients. Surveys identified unmet needs of patient care, patients having little information on national support systems and structural deficits of healthcare systems to ensure HCP can provide adequate clinical care during transition phases. These results are collected by MetabERN and forwarded to the Directorate-General for Health and Food Safety (DG SANTE) of the European Commission (EC) to be addressed further.Conclusion:MetabERN offers an infrastructure of virtual healthcare for patients with IMDs. Thus, in collaboration with ERN ReCONNET, MetabERN can assist in identifying rare metabolic disorders of RMDs to shorten the odyssey of diagnosis and advise on their respective therapies. On the other hand, MetabERN can benefit from EULAR’s longstanding experience regarding issues affecting the quality of life, all RMD patients are facing, such as pain, stiffness, fatigue, rehabilitation, maintaining work and disability claims.References:[1]IEMbase - Inborn Errors of Metabolism Knowledgebase http://www.iembase.org/ (accessed Jan 29, 2021).[2]MetabERN: European Refence Network for Hereditary Metabolic Disorders https://metab.ern-net.eu/ (accessed Jan 29, 2021).[3]Lampe, C.; Dionisi-Vici, C.; Bellettato, C. M.; Paneghetti, L.; van Lingen, C.; Bond, S.; Brown, C.; Finglas, A.; Francisco, R.; Sestini, S.; Heard, J. M.; Scarpa, M.; MetabERN collaboration group. The Impact of COVID-19 on Rare Metabolic Patients and Healthcare Providers: Results from Two MetabERN Surveys. Orphanet J. Rare Dis.2020, 15 (1), 341. https://doi.org/10.1186/s13023-020-01619-x.Acknowledgements:The authors thank the MetabERN collaboration group, the single point of contacts (SPOC) of the MetabERN patient board and the Transition Project Working Group (TPWG)Disclosure of Interests:None declared

The effects of corporate brand symbolism on consumer satisfaction and loyalty

2016 ◽  
Vol 28 (3) ◽  
pp. 481-498 ◽  
Author(s):  
Tatiana Anisimova
Keyword(s):  
Social Life ◽  
Consumer Satisfaction ◽  
Single Point ◽  
Social Aspects ◽  
Consumer Loyalty ◽  
Cross Sectional ◽  
Corporate Brand ◽  
Content Type ◽  
Strategic Role ◽  
The Impact

Purpose – The purpose of this paper is to test the effects of corporate brand symbolism on consumer satisfaction and loyalty on a sample of Australian automobile consumers. Design/methodology/approach – Survey research was employed to test the study hypotheses. The regression analysis was used to evaluate the relationships between an independent variable (corporate brand symbolism) and dependent variables (consumer satisfaction and loyalty). Findings – Support was found for all hypotheses formulated in this study. Regression results reveal consistent favourable and significant effects of corporate brand symbolism on both consumer satisfaction and loyalty. Research limitations/implications – Although this paper makes contributions in international marketing, the cross-sectional nature of the data collection method limits the information gained to the single point in time. This research studied the impact of corporate brand symbolism on consumers of one original equipment manufacturers (OEM). Having a larger number of participating car manufacturers/OEMs would have provided a wider insight. However, time and resources limitation did not allow to study a larger sample. In the future, practitioners are recommended to further understand the relationship between self and social aspects of brand symbolism in order to formulate more targeted communication strategies. Practical implications – The findings of this study point to the strategic role of the brand in generating both satisfaction and loyalty. In the light of increasing advertising costs and decreasing consumer loyalty, strengthening corporate brand symbolism makes a lot of economic sense. The findings suggest that managers need to take into account consumer need for identity expression and consider this in their branding strategies. Social implications – Humans are social beings by nature. However, international brand research has paid relatively little attention to how products are used by consumers in everyday life, including their social life. Consumer behaviours increasingly depend on social meanings they imbue brands with beyond products’ functional utility. It is argued the focus of symbolic consumption needs to be broadened and integrated more with social science concepts. Originality/value – This study captures a construct of corporate brand symbolism by including self and social aspects of symbolism. The current study also comprehensively measures consumer loyalty, including cognitive, affective and behavioural types of loyalty.

A normal section plane method for profile error analysis of five-axis machine tools based on the ideal tool flank milling surface

2021 ◽  
pp. 095440622110426
Author(s):  
Liping Wang ◽  
Meng Fu ◽  
Liwen Guan ◽  
Yanyu Chen
Keyword(s):  
Contact Point ◽  
Flank Milling ◽  
Section Plane ◽  
Profile Error ◽  
Plane Method ◽  
Normal Section ◽  
Accuracy Measurement ◽  
Machine Tool Accuracy ◽  
Milled Surface ◽  
The Impact

The existing studies on profile error analysis and machining accuracy measurement do not consider the impact of the theoretical errors on the machine tool accuracy measurement. Therefore, this study proposes an estimation method of the surface profile error based on the normal section plane, using the theoretical flank milled surface for comparison. This effectively improves the accuracy of profile error estimation. The theoretical flank milled surface is the surface machined by flank milling under ideal conditions. Hence, compared to the traditional analysis method based on the designed three-dimensional model of S-shaped test pieces, the calculated profile error of this method does not include theoretical errors, thereby eliminating the impact of theoretical errors on machine tool accuracy measurement and evaluation. First, an improved method for continuous parameterized dual spline interpolation was proposed. It simplifies the solution of the singular problem of the coefficient matrix of the spline basis function and obtains a continuous ideal machining tool axis trajectory surface with complete geometric characteristics. Next, a method for constructing the theoretical flank milled surface machined with a cylindrical milling tool using equidistant mapping characteristics was proposed; then, the differential transformation relationship at the cutting contact point of the curved surface under the influence of tool path errors was established. Furthermore, the normal section plane method based on the differentiation of the cutting contact point was proposed. The problem of solving the distance from a point to a surface is converted to the problem of solving the distance from a point to a curve in the normal section plane. This improves the accuracy of profile error estimation. The effectiveness of the method was verified by comparing the analysis results of the profile errors of a typical cylindrical surface with the point to surface and the point to curve methods.

Resolving the Unique Invariant Slip-Direction in Rigid Three-Dimensional Multi-Point Impacts at Stick-Slip Transitions

2018 ◽  
Author(s):  
Abhishek Chatterjee ◽  
Alan Bowling
Keyword(s):  
Single Point ◽  
Three Dimensional ◽  
Impact Behavior ◽  
Slip Direction ◽  
Stick Slip ◽  
Impact Forces ◽  
Post Impact ◽  
Impact Problems ◽  
Slip Transition ◽  
The Impact

This work presents a new approach for resolving the unique invariant slip direction at Stick-Slip Transition during impact. The solution method presented in this work is applicable to both single-point and multi-point impact problems. The proposed method utilizes rigid body constraints to resolve the impact forces at all collision points in terms of a single independent impact forces parameter. This work also uses an energetic coefficient of restitution to terminate impact events, thereby yielding energetically consistent post-impact behavior.

Investigation on three-directional dynamic interaction between a heavy-duty vehicle and a curved bridge

2017 ◽  
Vol 21 (5) ◽  
pp. 721-738 ◽  
Author(s):  
Shaohua Li ◽  
Jianying Ren
Keyword(s):  
Interaction Model ◽  
Element Model ◽  
Driver Model ◽  
Impact Factors ◽  
Lateral Impact ◽  
Heavy Duty ◽  
Vehicle Model ◽  
Curved Bridge ◽  
Bridge Model ◽  
The Impact

Considering the nonlinear property of suspension damping and tire stiffness, a full-vehicle model is built for a heavy-duty truck. A modified preview driver model with nonlinear time delay is inserted into the vehicle model to compute the suitable steering angle of the front wheel and to make the vehicle follow the required route. Next, the finite element model of a five-span continuous curved highway bridge is established, and the bridge’s inherent frequencies and modes are obtained. The curved bridge and the vehicle are coupled by three-directional tire forces, and a three-directional driver–vehicle–bridge interaction model is presented. The presented vehicle model and bridge model are verified by comparing with the published works. The dynamic impact factors of vertical, lateral, and torsional displacements of the bridge are calculated when a vehicle is traversing through the bridge, and the impact factors’ distributions along the bridge are analyzed. The effects of vehicle driving conditions on impact factors are also researched. It is found that the impact factor calculated from the present specification for a straight bridge is smaller than that from the three-directional driver–vehicle–bridge interaction model, and the vertical and torsional impact effects at the third span midpoint are greater than the lateral impact effect.

scholarly journals The role of the factors determining national character in building civil society

2021 ◽  
Vol 39 (69) ◽  
pp. 774-795
Author(s):  
Serhii O. Komnatnyi ◽  
Oleg S. Sheremet ◽  
Viacheslav E. Suslykov ◽  
Kateryna S. Lisova ◽  
Stepan D. Svorak
Keyword(s):  
Civil Society ◽  
Climatic Conditions ◽  
The State ◽  
National Character ◽  
The Political ◽  
Main Research ◽  
Mechanism Of Impact ◽  
Two Stages ◽  
The Impact

The article deals with the mechanism of impact of sociopsychological phenomena such as the national character and the political mentality in the construction and functioning of civil society. It aims to show the impact of climate, religion, and the perception of happiness on the state of civil society through details of a national nature. The main research method is to compare data from global research on the state of civil society with data from climatic conditions, dominant religions, and happiness indices. The article proves coincidently that these factors are reflected in such essential characteristics of civil society as "openness" and "closed-mindedness". The interaction between the national character and the construction of civil society has two stages. It is concluded that the results obtained are important to evaluate the prospects for the construction and development of civil society in different countries and regions of the world. Further research in this direction involves the study of other aspects of the impact of national character and political mindset on the functioning of civil society.

Analysis and Mechanism of Impact of GPR Detection Effect Result from Soil Water Content

2012 ◽  
Vol 226-228 ◽  
pp. 2098-2102 ◽  
Author(s):  
Xin Jing Wang ◽  
Zhen Qi Hu ◽  
Yan Ling Zhao ◽  
Yu Ming Guo ◽  
Pei Jun Wang
Keyword(s):  
Water Content ◽  
Soil Water ◽  
Soil Water Content ◽  
Amplitude Spectrum ◽  
Image Interpretation ◽  
Soil Taxonomy ◽  
Underground Pipe ◽  
Mechanism Of Impact ◽  
The Impact ◽  
Detection Effect

Using the ground-penetrating radar (GPR) system with the different frequencies and neutron probe, combing with radar image interpretation and the amplitude spectrum, the impact of GPR detection effects on the soil taxonomy and underground pipe were analyzed. The results indicate that when the soil content is 17.02%, the effect on soil taxonomy of 750MHZ antenna is better than 400MHZ, but the effect on underground pipe is same. As soil water content increases to 25.333%, the soil taxonomy of two antennas’ detection tends to same, and “fake stratifications” existed. The soil water content accelerates to 36.389%, the detection effect on soil taxonomy and underground pipe is so poor. Attenuation mechanism and propagation characteristics of the high electromagnetic wave were presented to interpret those phenomena. The above analysis shows that the soil water content is one of the main prerequisites for the applications of GPR. Some indicators could be provided to nondestructive test in land consolidation project quality by GPR from this research.

Risk Analysis of Live Fire Shoot House Containment Systems Against Multiple Projectile Impacts

2020 ◽  
Author(s):  
Steven D. Andreen ◽  
Brad G. Davis
Keyword(s):  
Normal Distribution ◽  
Numerical Models ◽  
Single Point ◽  
Experimental Results ◽  
Risk Level ◽  
Triangular Distribution ◽  
Repeated Impact ◽  
Steel Panels ◽  
The Impact ◽  
Projectile Impacts

Abstract Many analytical and numerical models exist that can describe the effect of single projectile impacts on steel targets. These models are not adequate for the evaluation of live fire shoot house containment systems, which are subjected to repeated impact loading from small caliber projectiles over the lifetime of the structure. Models assuming perfectly rigid projectiles over-predict penetration depths. Models assuming rigid targets cannot predict any penetration, and hydrodynamic models are best suited to high velocity impacts well above the ranges of conventional ordinance. Development of sufficient analytical or numerical tools using traditional techniques would be either intractable, empirically based and unique to a given scenario, require unique material properties that are not commonly available, or require significant computational effort. Due to the limited amount of empirical data on multiple impact failure, classical reliability methods are not suitable for assessing the probability of containment system perforation. Using existing experimental results of .223 caliber ammunition against AR500 steel panels with 2-inch ballistic rubber, a commonly found protective system in these facilities, the cumulative effects of multiple projectiles were quantified to estimate the number of impacts required to perforate the target material. Impacts were simulated from normal distributions of the x and y coordinates describing the impact point using a cartesian coordinate plane. The impact resistance of the steel was also simulated from a triangular distribution to account for the variability of the experimental results. Monte Carlo Simulation was then used to estimate the expected number of impacts to cause failure at a single point on the target. Using this collective model, it was possible to determine that the distribution of the number of rounds to cause target failure approached a normal distribution. The results indicated that the mean impacts at failure was 11800 with a standard deviation of 800 impacts. Finally, targeting the allowable risk level for structural failure from the JCSS probabilistic model code from the simulated normal distribution, it was determined that the safe number of impacts was approximately 7996. Decision makers can utilize the safe number of impacts to inform training guidance for the future use of facilities and to develop effective inspection requirements. This model can also be adapted to evaluate similar training facilities and to assess how other small caliber projectile impacts would affect live fire shoot house containment systems, providing a useful tool for the design and analysis of future and the assessment of existing facilities for use with ammunition that did not exist during its design.

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