Uniformity: A Crucial Attribute of Tire/Wheel Assemblies

2010 ◽  
Vol 38 (1) ◽  
pp. 24-46 ◽  
Author(s):  
M. G. Pottinger
Keyword(s):  
Structural Dynamics ◽  
Dynamic Properties ◽  
Small Degree ◽  
Critical Component ◽  
Road Vehicles ◽  
Light Trucks ◽  
Surface Irregularities ◽  
The Subject ◽  
Tire Rotation ◽  
Energy Share

Abstract Good ride, acceptable comfort for passengers, is a required attribute for all road vehicles particularly automobiles and light trucks. The tire/wheel assembly is a critical component in providing good ride. Indeed, obtaining good ride was the crucial factor that drove the invention of and rapid popularization of the pneumatic tire. Today, the ride effect of tires is often thought of in two ways. The first is in terms of the transmission of vibration produced by the interaction of the tire with road surface irregularities, harshness. The second is in terms of tire structural irregularity generated energy transmitted during operation on a smooth road, uniformity. Both types of energy share the dynamic properties of the tire structure though they differ in source. This paper concentrates primarily on uniformity induced vibration particularly at the frequency of tire rotation, but does touch on harshness to a small degree, when the sharing of structural dynamics makes it appropriate. This review of the subject of force uniformity includes the effect of wheels, as wheels contribute to the vibration that reaches the vehicle spindle. Balance is touched on only as it affects force uniformity in well-balanced assemblies. This is not a treatise on balancing. A suggestion is made, which should, if practical, greatly improve the installed uniformity of tire/wheel assemblies.

Conclusion

2018 ◽  
Author(s):  
Stephanie L. Derrick
Keyword(s):  
Social Mobility ◽  
Social Factors ◽  
Critical Component ◽  
Critical Difference ◽  
Middle Classes ◽  
Print History ◽  
Social Divisions ◽  
Equal Importance ◽  
The Social ◽  
The Subject

The emphasis of this monograph has been on the historical, cultural, religious, and social factors that shaped C. S. Lewis and his reception. Until recently those who have considered the subject have attributed his popularity to virtues of the man himself. The fact that Lewis, in effect, was an image, a mitigated commercial product, a platform, has largely been overlooked. A critical component of Lewis’s reception is the opportunities that education provided the middle classes for social mobility in the twentieth century and the social divisions and anxieties attendant upon those evolutions. Of equal importance is the timing of Lewis’s life and publications with print history and the rise of mass media and entertainment. Lewis’s platform as a contrarian Christian resisting modernity and his reactions to the intellectual, social, and religious changes of his day made the critical difference to his transatlantic receptions.

scholarly journals MARXISMO, SUJEITO E SUBJETIVIDADE. NEGRI DIANTE DO ANTI-HUMANISMO ALTHUSSERIANO

Sapere Aude ◽  
2019 ◽  
Vol 10 (19) ◽  
pp. 250-273
Author(s):  
Émerson Pirola
Keyword(s):  
Political Economy ◽  
Social Class ◽  
Structural Dynamics ◽  
Class Struggle ◽  
Louis Althusser ◽  
The Subject ◽  
Abstract Notion ◽  
The 1960S ◽  
The One ◽  
Antonio Negri

Um debate de longa data no interior do marxismo é o entre perspectivas que tenderiam para uma leitura da obra marxiana centrada nas análises sobre a constituição de sujeitos políticos de e em luta, na constituição de uma classe social revolucionária que enfrente a exploração capitalista, e perspectivas centradas nas transformações do capitalismo ou nas dinâmicas estruturais da economia. Podemos dizer, esquematicamente, que as primeiras perspectivas são “subjetivistas” e as segundas “objetivistas”. Nos anos 1960 esse debate se viu determinado pela chamada polêmica do anti-humanismo, lançada por Louis Althusser contra o marxismo por ele criticado como humanista, visto que advogaria por uma noção de Sujeito idealista e abstrata, descolada dos processos estruturais da economia política capitalista. Antonio Negri, por sua vez, deu e dá grande importância para a noção de subjetividade na análise crítica e enfrentamento do capitalismo. Negri, entretanto, não ignora as críticas efetuadas por Althusser ao chamado humanismo, tomando-as como pré-requisito para o desenvolvimento original de sua teoria. Mostramos, portanto, como Althusser desenvolve suas críticas do Sujeito e do humanismo para então desenvolver as posições de Negri diante destas, a construção de sua própria teoria da subjetividade, resgatada do Marx dos Grundrisse, e apontar as limitações do pensamento althusseriano no que concerne à subjetividade.PALAVRAS-CHAVE: Sujeito. Anti-humanismo. Subjetividade. Negri. Althusser. ABSTRACTA long-standing debate within Marxism is the one between perspectives that would tend towards a reading of the Marxian work centered on analyzes of the constitution of political subjects in and in class struggle, the constitution of a revolutionary social class facing capitalist exploitation, and perspectives centered on the transformations of capitalism or the structural dynamics of the economy in general. We can say, schematically, that the first perspective are "subjectivist" and the second one "objectivist". In the 1960s this debate was determined by Louis Althusser's so-called polemic of anti-humanism, in which he criticized certain Marxism as an humanism, since it would advocate for an idealist and abstract notion of subject detached from the structural processes of capitalist political economy. Antonio Negri, in turn, gave and gives great importance to the notion of subjectivity in the dynamics and confrontation of capitalism. Negri, however, does not ignore the criticisms made by Althusser of the humanism, taking them as a prerequisite for the original development of his theory. We thus show how Althusser develops his criticisms of the Subject and humanism to develop Negri's positions for and against them, the construction of his own theory of subjectivity, rescued from Marx’s Grundrisse, and we point out the limitations of Althusser's thought as regards subjectivity.KEYWORDS: Subject. Antihumanism. Subjeticvity. Negri. Althusser.

Neural Networks for the Simulation and Identification Analysis of Buildings Subjected to Paraseismic Excitations

2007 ◽  
pp. 393-432 ◽  
Author(s):  
Krystyna Kuzniar ◽  
Zenon Waszczyszyn
Keyword(s):  
Neural Networks ◽  
Structural Dynamics ◽  
Dynamic Properties ◽  
Response Spectra ◽  
Engineering Practice ◽  
Identification Analysis ◽  
Dynamics Problems ◽  
Mining Tremors ◽  
Testing Patterns ◽  
Mining Regions

The chapter deals with an application of neural networks to the analysis of vibrations of medium-height prefabricated buildings with load-bearing walls subjected to paraseismic excitations. Neural network technique was used for identification of dynamic properties of actual buildings, simulation of building responses to paraseismic excitations as well as for the analysis of response spectra. Mining tremors in strip mines and in the most seismically active mining regions in Poland with underground exploitation were the sources of these vibrations. On the basis of the experimental data obtained from the measurements of kinematic excitations and dynamic building responses of actual structures the training and testing patterns were formulated. It was stated that the application of neural networks enables us to predict the results with accuracy quite satisfactory for engineering practice. The results presented in this chapter lead to a conclusion that the neural technique gives new prospects of efficient analysis of structural dynamics problems related to paraseismic excitations.

The Braking of Heavy Road Vehicles in Combination with Articulated and Independent Trailers

1972 ◽  
Vol 186 (1) ◽  
pp. 821-825
Author(s):  
C. E. Johnsson ◽  
N. G. Dahlkvist
Keyword(s):  
United Kingdom ◽  
Road Vehicles ◽  
Line System ◽  
Load Sensing ◽  
Braking System ◽  
The United Kingdom ◽  
The Subject ◽  
Better Than

A two-line braking system is described as being as safe as and better than the three-line system currently used in the United Kingdom. How this system can be achieved, in line with European thinking on the subject, is also reported. To maintain the improvement obtained by using a two-line system, spring brakes, emergency operated by means of a ‘kick-down’ release valve, true brake balance using load sensing valves, reliable anti-skid devices and automatic slack adjusters is discussed.

scholarly journals MreB Forms Subdiffraction Nanofilaments during Active Growth in Bacillus subtilis

mBio ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. e01879-18 ◽  
Author(s):  
Cyrille Billaudeau ◽  
Zhizhong Yao ◽  
Charlène Cornilleau ◽  
Rut Carballido-López ◽  
Arnaud Chastanet
Keyword(s):  
Cell Wall ◽  
Dynamic Properties ◽  
Cell Envelope ◽  
Side Wall ◽  
Active Growth ◽  
Content Type ◽  
Gram Positive Bacteria ◽  
Entire Cell ◽  
The Subject ◽  
True Structure

ABSTRACT The actin-like MreB protein is a key player of the machinery controlling the elongation and maintenance of the cell shape of most rod-shaped bacteria. This protein is known to be highly dynamic, moving along the short axis of cells, presumably reflecting the movement of cell wall synthetic machineries during the enzymatic assembly of the peptidoglycan mesh. The ability of MreB proteins to form polymers is not debated, but their structure, length, and conditions of establishment have remained unclear and the subject of conflicting reports. Here we analyze various strains of Bacillus subtilis, the model for Gram-positive bacteria, and we show that MreB forms subdiffraction-limited, less than 200 nm-long nanofilaments on average during active growth, while micron-long filaments are a consequence of artificial overaccumulation of the protein. Our results also show the absence of impact of the size of the filaments on their speed, orientation, and other dynamic properties conferring a large tolerance to B. subtilis toward the levels and consequently the lengths of MreB polymers. Our data indicate that the density of mobile filaments remains constant in various strains regardless of their MreB levels, suggesting that another factor determines this constant. IMPORTANCE The construction of the bacterial cell envelope is a fundamental topic, as it confers its integrity to bacteria and is consequently the target of numerous antibiotics. MreB is an essential protein suspected to regulate the cell wall synthetic machineries. Despite two decades of study, its localization remains the subject of controversies, its description ranging from helical filaments spanning the entire cell to small discrete entities. The true structure of these filaments is important because it impacts the model describing how the machineries building the cell wall are associated, how they are coordinated at the scale of the entire cell, and how MreB mediates this regulation. Our results shed light on this debate, revealing the size of native filaments in B. subtilis during growth. They argue against models where MreB filament size directly affects the speed of synthesis of the cell wall and where MreB would coordinate distant machineries along the side wall.

scholarly journals The diurnal variation of terrestrial magnetism

1914 ◽  
Vol 89 (612) ◽  
pp. 379-392 ◽  
Keyword(s):  
Experimental Study ◽  
Diurnal Variation ◽  
Observational Data ◽  
Theoretical Investigation ◽  
Small Degree ◽  
Law And Order ◽  
Terrestrial Magnetism ◽  
The Earth ◽  
Reasonable Proportion ◽  
The Subject

The diurnal variation of terrestrial magnetism has been the subject of experimental study for many years, and at a considerable number of observatories scattered all over the earth. But the co-ordination of the results, and the theoretical investigation of the physical cause or causes of the phenomena, have not made progress which seems to bear a reasonable proportion to the vast amount of observational data that has accumulated. As far as I know, Dr. Arthur Schuster’s memoirs constitute the most inspiring and systematic attempt to reduce this matter to scientific law and order. Although I have found it convenient to depart from the method pursued by Schuster, this change of procedure was in no small degree suggested by various remarks in his memoirs.

scholarly journals Static and dynamic properties of selected stochastic processes on complex networks

2020 ◽  
Author(s):  
Jeremi Ochab
Keyword(s):  
Random Walk ◽  
Complex Networks ◽  
Random Walks ◽  
Dynamic Properties ◽  
Finite Size ◽  
Disease Spread ◽  
Maximal Entropy ◽  
Centrality Measures ◽  
Topological Features ◽  
The Subject

This thesis is concerned with the properties of a number of selected processes taking place on complex networks and the way they are affected by structure and evolution of the networks. What is meant here by 'complex networks' is the graph-theoretical representations and models of various empirical networks (e.g., the Internet network) which contain both random and deterministic structures, and are characterised among others by the small-world phenomenon, power-law vertex degree distributions, or modular and hierarchical structure. The mathematical models of the processes taking place on these networks include percolation and random walks we utilise.The results presented in the thesis are based on five thematically coherent papers. The subject of the first paper is calculating thresholds for epidemic outbreaks on dynamic networks, where the disease spread is modelled by percolation. In the paper, known analytical solutions for the epidemic thresholds were extended to a class of dynamically evolving networks; additionally, the effects of finite size of the network on the magnitude of the epidemic were studied numerically. The subject of the second and third paper is the static and dynamic properties of two diametrically opposed random walks on model highly symmetric deterministic graphs. Specifically, we analytically and numerically find the stationary states and relaxation times of the ordinary, diffusive random walk and the maximal-entropy random walk. The results provide insight into localisation of random walks or their trapping in isolated regions of networks. Finally, in the fourth and fifth paper, we examine the utility of random walks in detecting topological features of complex networks. In particular, we study properties of the centrality measures (roughly speaking, the ranking of vertices) based on random walks, as well as we conduct a systematic comparative study of random-walk based methods of detecting modular structure of networks.These studies thus aimed at specific problems in modelling and analysis of complex networks, including theoretical examination of the ways the behaviour of random processes intertwines with the structure of complex networks.

Analysis of the Damping of Beams With Discontinuous Viscoelastic Damping Layer Using Integral Finite Elements

Volume 2 ◽  
2004 ◽  
Author(s):  
T. Liang ◽  
Qian Chen ◽  
S. Olutunde Oyadiji ◽  
Andrew Leung
Keyword(s):  
Finite Elements ◽  
Structural Dynamics ◽  
Degrees Of Freedom ◽  
Dynamic Properties ◽  
Viscoelastic Damping ◽  
Fe Model ◽  
Dynamics Analysis ◽  
Viscoelastic Composite ◽  
Constraint Damping ◽  
Damping Treatments

The damping performance of discontinuous constrained viscoelastic damping layer using Integral Finite Elements (IFE) are investigated in this paper. The IFE involves the dynamic analysis of Elastic-Viscoelastic Composite (EVC) structures with frequency-dependant material properties. EVC structures, which incorporate constrained viscoelastic damping treatment, are modelled using IFE’s and conventional FE’s together to deal with the discontinuous treatment of the constraint damping layers. This approach dramatically reduces the number of degrees of freedom of the FE model compared with conventional FE models. By using specialised algorithms developed for EVC structural dynamics analysis, IFE makes the estimation of the dynamic properties of the EVC structures an easy task similar to the structural dynamics analysis using conventional finite element method. Using an IFE model and the special algorithms, the damping performance of various designs of viscoelastic damping treatments are investigated at extremely low computational costs compared with the use of current commercial FE software packages. A guideline is introduced based on the results of the damping performance analysis for the structural design of viscoelastic damping treatments.

scholarly journals VIII.—Histological Observations on the Muscular Fibre and Connective Tissue of the Uterus during Pregnancy and the Puerperium

1890 ◽  
Vol 35 (2) ◽  
pp. 359-376 ◽  
Author(s):  
T. Arthur Helme
Keyword(s):  
Connective Tissue ◽  
Inflammatory Process ◽  
Fatty Degeneration ◽  
Single Fibre ◽  
Small Degree ◽  
Normal Process ◽  
Human Uterus ◽  
Fatty Change ◽  
Child Birth ◽  
The Subject

The study of a normal process in an organ so especially prone to disease as is the human uterus, is beset with many difficulties; so many foreign conditions are apt to be present, giving a false impression as to what this process really is. That this is the case to no small degree, when the character of the changes which occur in the normal involution of the uterus after child-birth is the subject of observation, is shown by the variety of opinions held and stated by doubtlessly competent observers; for while one holds that the muscle undergoes a fatty degeneration, another holds that no such fatty change occurs; while one asserts that only a certain number of the fibres degenerate and disappear, another states that so complete is the destruction, that not one single fibre present in the uterus before birth survives the process; while another goes to the extent of saying, that the puerperal uterus can in no way be distinguished from a uterus that has undergone an inflammatory process.

ERPS AS AN INDEX OF IMPAIRED WORKING MEMORY IN AN ISCHEMIC BRAIN STROKE APHASIC PATIENT AWAKENED FROM A LONG-TERM COMA FOLLOWING AN AMPHETAMINE OVERDOSE

2021 ◽  
Vol 19 (2) ◽  
pp. 137-145
Author(s):  
Ewa Wilczek-Rużyczka ◽  
Celestyna Grzywniak ◽  
Maciej Korab ◽  
Ksenia Cielebąk
Keyword(s):  
Prescription Drugs ◽  
Functional Neuroimaging ◽  
Small Degree ◽  
Cortical Blindness ◽  
Health Concern ◽  
Temporal Area ◽  
Charles Bonnet Syndrome ◽  
Grand Average ◽  
The Subject

Nowadays, amphetamines constitute the prescription drugs most commonly abused by adolescents and young adults (Berman, O’Neill, Fears et al. 2008). The prevalence of problematic (mainly illegal) use of amphetamines as a stimulant by college students, and here especially before serious examinations, has also been rising. This fact represents a serious public health concern. The patient, aged 19, was awakened from from a long-term coma that had lasted 21 days following an amphetamine overdose and manifested tetraparesis, cortical blindness and deficits in cognitive and emotional processes. After a year of rehabilitation the majority of symptoms had disappeared, but cortical blindness andworking memory deficits remained. In addition, frontal lobe syndrome symptoms appeared. After two years of therapy as a result of immense tiredness caused by all an night wedding reception she started to manifest Charles-Bonnet syndrome. She experienced strange visual sensations such as visual hallucinations and saw various non-existing shapes (coloured blots, patterns and fireworks of vivid colours). She also saw objects (often terrifying) as well as animals (mainly African) and people with deformed faces and long teeth, and persons in African dress with feathers and coral beads in their hair. Her real identity was not remembered by the patient for longer than 2 hours and even then she insisted on being referred to as Shakira. She was given a qEEG examination (in open and closed eyes conditions) and ERPs with the use of auditory stimuli at the period when the hallucinations (to a small degree) still occurred. Studies conducted into the functional neuroimaging of the brain work in milliseconds in the examined patient can explain her symptoms. A comparison of the subject’s ERPs with the grand average of ERPs in healthy controls shows that the N170 and N 250 components are impaired in the subject: the occipital-temporal area of the subject brain shows a strong positivity instead of negativities. This positivity might reflect an enhanced reactivity of neurons in the corresponding area induced by the removal of lateral inhibition from the neurons as a result of local damage. ------------------------------------------------------------------------------------------------------------------------------------

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