Analysis and Design for Zero Impact Wear

1974 ◽  
Vol 96 (3) ◽  
pp. 455-461 ◽  
Author(s):  
P. A. Engel
Keyword(s):  
Impact Wear ◽  
Analysis And Design ◽  
Surface Fatigue ◽  
Wear Life ◽  
Solution Methods ◽  
Life Analysis ◽  
Impact Problems ◽  
Elastically Restrained ◽  
Stress Dependent

Wear life analysis methods are set forth for mechanical components subjected to a large number of repeated compound impacts (normal impact coupled with relative sliding). The wear mechanism in the elastic stress range is surface fatigue, and wear life is strongly contact-stress dependent. Several typical impact problems are discussed in conjunction with analytical and experimental solution methods. A general impact wear formulation is presented for two elastically restrained bodies. The role of lubrication is discussed. Some charts and diagrams are given to aid quantitative treatment.

scholarly journals Transcription Factors Pcr1 and Atf1 Have Distinct Roles in Stress- and Sty1-Dependent Gene Regulation

2008 ◽  
Vol 7 (5) ◽  
pp. 826-835 ◽  
Author(s):  
Miriam Sansó ◽  
Madelaine Gogol ◽  
José Ayté ◽  
Chris Seidel ◽  
Elena Hidalgo
Keyword(s):  
Mitogen Activated Protein Kinase ◽  
Transcriptional Responses ◽  
Repressive Effect ◽  
Mitogen Activated Protein ◽  
Promote Cell Survival ◽  
Stress Dependent ◽  
Microarray Analyses ◽  
Stress Activation

ABSTRACT The mitogen-activated protein kinase Sty1 is essential for the regulation of transcriptional responses that promote cell survival in response to different types of environmental stimuli in Schizosaccharomyces pombe. Upon stress activation, Sty1 reversibly accumulates in the nucleus, where it stimulates gene expression via the Atf1 transcription factor. The Atf1 protein forms a heterodimer with Pcr1, but the specific role of this association is controversial. We have carried out a comparative analysis of strains lacking these proteins individually. We demonstrate that Atf1 and Pcr1 have similar but not identical roles in S. pombe, since cells lacking Pcr1 do not share all the phenotypes reported for Δatf1 cells. Northern blot and microarray analyses demonstrate that the responses to specific stresses of cells lacking either Pcr1 or Atf1 do not fully overlap, and even though most Atf1-dependent genes induced by osmotic stress are also Pcr1 dependent, a subset of genes require only the presence of Atf1 for their induction. Whereas binding of Atf1 to most stress-dependent genes requires the presence of Pcr1, we demonstrate here that Atf1 can bind to the Pcr1-independent promoters in a Δpcr1 strain in vivo. Furthermore, these analyses show that both proteins have a global repressive effect on stress-dependent and stress-independent genes.

Developing annotation solutions for online Data Driven Learning

ReCALL ◽  
2009 ◽  
Vol 21 (1) ◽  
pp. 55-75 ◽  
Author(s):  
Pascual Pérez-Paredes ◽  
Jose M. Alcaraz-Calero
Keyword(s):  
Corpus Linguistics ◽  
Language Teaching ◽  
Language Education ◽  
Data Driven ◽  
Online Data ◽  
Analysis And Design ◽  
Language Classroom ◽  
Youth Language ◽  
User Friendly

AbstractAlthough annotation is a widely-researched topic in Corpus Linguistics (CL), its potential role in Data Driven Learning (DDL) has not been addressed in depth by Foreign Language Teaching (FLT) practitioners. Furthermore, most of the research in the use of DDL methods pays little attention to annotation in the design and implementation of corpus-based/driven language teaching.In this paper, we set out to examine the process of development of SACODEYL Annotator, an application that seeks to assist SACODEYL system users in annotating XML multilingual corpora. First, we discuss the role of annotation in DDL and the dominating paradigm in general corpus applications. In the context of the language classroom, we argue that it is essential that corpora should be pedagogically motivated (Braun, 2005 and 2007a). Then, we move on to deal with the analysis and design stages of our annotation solution by illustrating its main features. Some of these include a user friendly hierarchical and extensible taxonomy tree to facilitate the learner-oriented annotation of the corpora; real-time graphics representation of the annotated corpus matching the XML TEI-compliant (Text Encoding Initiative) standard, as well as an intuitive management of the different data sections and associated metadata.SACODEYL (System Aided Compilation and Open Distribution of European Youth Language) is an EU funded MINERVA project which aims to develop an ICT-based system for the assisted compilation and open distribution of multimedia European teen talk in the context of language education. This research lays emphasis on the functionalities of the application within the SACODEYL context. However, our paper addresses similarly the needs of potential multimedia language corpus administrators in general on the lookout for powerful annotation assisting software. SACODEYL Annotator is free to use and can be downloaded from our website.

scholarly journals Mechanisms of Response to Salt Stress in Oleander (Nerium oleander L.)

2016 ◽  
Vol 73 (2) ◽  
pp. 249
Author(s):  
Dinesh Kumar ◽  
Mohamad Al Hassan ◽  
Oscar Vicente ◽  
Veena Agrawal ◽  
Monica Boscaiu
Keyword(s):  
Salt Stress ◽  
Abiotic Stress Tolerance ◽  
Soluble Sugar ◽  
Soluble Sugars ◽  
Nerium Oleander ◽  
Antioxidant Systems ◽  
Change Scenario ◽  
Antioxidant Compounds ◽  
Stress Dependent

Elucidating the mechanisms of abiotic stress tolerance in different species will help to develop more resistant plant varieties, contributing to improve agricultural production in a climate change scenario. Basic responses to salt stress, dependent on osmolyte accumulation and activation of antioxidant systems, have been studied in Nerium oleander, a xerophytic species widely used as ornamental. Salt strongly inhibited growth, but the plants survived one-month treatments with quite high NaCl concentrations, up to 800 mM, indicating the the species is relatively resistant to salt stress, in addition to drought. Levels of proline, glycine betaine and soluble sugars increased only slightly in the presence of salt; however, soluble sugar absolute contents were much higher than those of the other osmolytes, suggesting a functional role of these compounds in osmotic adjustment, and the presence of constitutive mechanisms of response to salt stress. High salinity generated oxidative stress in the plants, as shown by the increase of malondialdehyde levels. Antioxidant systems, enzymatic and non-enzymatic, are generally activated in response to salt stress; in oleander, they do not seem to include total phenolics or flavonoids, antioxidant compounds which did not accumulate significantly in salt-trated plants

The Wear Process Between Normally Impacting Elastic Bodies

1974 ◽  
Vol 96 (4) ◽  
pp. 595-604 ◽  
Author(s):  
P. A. Engel ◽  
R. G. Bayer
Keyword(s):  
Peak Strain ◽  
Impact Wear ◽  
Axially Symmetric ◽  
Surface Geometry ◽  
Normal Impact ◽  
Wear Process ◽  
Surface Fatigue ◽  
Elastic Bodies ◽  
Symmetric Configuration ◽  
The Impact

The wear process between two elastic bodies, repeatedly impacting in an axially symmetric configuration is investigated analytically and experimentally. The mechanism initiating wear is that of surface fatigue, and the paper aims to explain the geometric process of wear formation beyond the “zero wear limit.” In doing so, an engineering, predictive model is sought, whereby the depth of a worn crater is related to the stresses arising during impact and to the number of loading cycles on the specimen. Four major accomplishments are embodied in the paper: (1) the quasi-static analysis of impact on a medium of nonuniform (cratered) surface geometry, (2) a heuristic derivation of the optimum wearpath, (3) derivation of the partial differential equation of normal impact wear, and (4) computation of the impact wear process for two discrete impact wear configurations and comparison of experimental work with the analytical results. The resulting conclusion is that impact wear proceeds at continuously varying curvature until the soft body conforms to the shape of the hard indenter. By equating the hysteretic wear energy with a fraction of the peak strain energy, quantitative wear history predictions are made for discrete geometries, such as a hard sphere impacting against a soft plane. Some experimental results are given between steel and aluminum specimens, confirming the analytical predictions.

E-Waste Stream Analysis and Design Implications

2011 ◽  
Vol 133 (10) ◽  
Author(s):  
Minjung Kwak ◽  
Sara Behdad ◽  
Yuan Zhao ◽  
Harrison Kim ◽  
Deborah Thurston
Keyword(s):  
Product Design ◽  
Potential Role ◽  
Waste Stream ◽  
Waste Collection ◽  
Waste Recovery ◽  
Analysis And Design ◽  
Multiple Generations ◽  
Incoming Stream ◽  
Take Back

The quantity and age of the incoming stream of “feedstock” from product take-back systems are known as the major sources of the uncertainty that complicates the e-waste recovery. This paper presents the results of an analysis of data from an incoming stream for an e-waste collection center and analyzes the quantity and age of e-waste by product type and brand. The analysis results point out receiving of outdated products and processing of multiple generations, and brands of products at the same time are among main obstacles to the e-waste recovery. The potential role of product design in overcoming those obstacles is discussed with emphasis on design for upgrade, repurpose, and commonality.

Wear-life analysis of deep groove ball bearings based on Archard wear theory

2018 ◽  
Vol 32 (7) ◽  
pp. 3329-3336 ◽  
Author(s):  
Guangwei Yu ◽  
Wei Xia ◽  
Zhuoyuan Song ◽  
Rui Wu ◽  
Siling Wang ◽  
...  
Keyword(s):  
Ball Bearings ◽  
Wear Life ◽  
Deep Groove ◽  
Life Analysis

Structural Analysis and Design of Pre Heating Automotive Control System Based on AVR

2013 ◽  
Vol 456 ◽  
pp. 595-598
Author(s):  
Jing Bo Zhu ◽  
Jing Yan Wang
Keyword(s):  
Control System ◽  
Heating System ◽  
Structural Features ◽  
Automotive Control ◽  
Analysis And Design ◽  
Advantages And Disadvantages ◽  
Heated Air ◽  
Air Intake ◽  
Working Principle

ATmega8 of AVR chip was used in the automobile pre-heating control system. Automotive pre-heated working principle was analyzed. The system of the pre-heater was designed and the hardware composition of the heating system, the structural features and the role of each module was introduced. It was expounded the process control including the heated air intake phase, to the oil phase, ignition phase and work phase. At last, the advantages and disadvantages of the pre-heater were introduced.

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