scholarly journals The determination of fatigue limits under alternating stress conditions

1914 ◽  
Vol 90 (620) ◽  
pp. 411-425 ◽  
Keyword(s):  
Infinite Number ◽  
Fatigue Tests ◽  
Test Results ◽  
Railway Company ◽  
Standard Of Comparison ◽  
The Subject ◽  
Pull Tests ◽  
Push And Pull ◽  
The Relationship

In the year 1867 A. Wöhler, locomotive superintendent of a railway company in Berlin, exhibited at the Paris Exhibition the results of some experiments on the endurance of metals, and was thereupon engaged by the Prussian Government to carry out the more exhaustive enquiry into this subject with which his name is always associated. The results of his labours were published in 1871, and were highly appreciated, but few additional experiments were made until the subject was again taken up successively by Sir Benjamin Baker, Reynolds and Smith, Rogers, Stanton and bairstow, Eden, Rose and Cunningham, and Prof. Hopkinson. All these experiments are confined either to fatigue bending or to push and pull tests, using only steel or iron, whereas the present ones include a large number of torsion fatigue tests on various metals. Until comparatively recently there was no satisfactory standard of comparison for fatigue tests, the determination of the asymptote or limiting fatigue stress for an infinite number of revolutions from a few irregular test results leading to very uncertain conclusions, so much so that by some it was considered very doubtful whether there were any real fatigue limits, while others adopted as standards of comparison the fatigue stresses which would cause fractures at the millionth repetition. The first problem which had to be investigated was therefore to ascertain the relationship between the intensities of fatigue stresses and the numbers of repetitions of these stresses which would cause fracture; and, should this relationship be found to indicate the existence of a limiting stress for an infinite number of revolutions, or more briefly of a fatigue limit, then the next step would have to be its exact determination.

Aspects of the Determination of the Strength of Materials

1947 ◽  
Vol 51 (433) ◽  
pp. 65-68
Author(s):  
E. W. J. Mardles
Keyword(s):  
Brittle Fracture ◽  
Statistical Methods ◽  
Mechanical Test ◽  
Microscopical Examination ◽  
Test Results ◽  
Strength Of Materials ◽  
Recent Developments ◽  
The Subject ◽  
Griffith Theory

Some aspects of the determination of the strength of materials formed the subject of two meetings held jointly with the British Rheologists’ Club (President, Prof. E. N. da C. Andrade) and the Royal Aircraft Establishment in the Assembly Hall, Farnborough, on the 16th June, 1945, and with the Royal Aeronautical Society in the library at 4, Hamilton Place, on the 19th February, 1946, under the chairmanship of Sir Ben Lockspeiser.At the Farnborough meeting three papers were read, namely, “The investigation of failures in wood by microscopical examination” by M. C. Pryor and A. Rayne; “The effect of duration of loading on the strength of brittle materials” by C. Gurney; and “Application of statistical methods to mechanical test results” by B. Chalmers and E. R. W. Jones. At the London meeting Prof. N. F. Mott of Bristol University spoke on the “Griffith theory of cracks in solids and recent developments of this theory, with application to brittle fracture in glass and in metals.”

Relationship Between Fatigue Life Distribution, Notch Configuration, and S-N Curve of a 2024-T4 Aluminum Alloy

1985 ◽  
Vol 107 (3) ◽  
pp. 214-220 ◽  
Author(s):  
T. Shimokawa ◽  
Y. Hamaguchi
Keyword(s):  
Aluminum Alloy ◽  
Fatigue Life ◽  
Stress Amplitude ◽  
Fatigue Tests ◽  
Test Results ◽  
Notched Specimens ◽  
Wide Range ◽  
Life Distributions ◽  
The Relationship ◽  
Test Stress

The objective of this study is to identify the most closely related variable to the distribution of fatigue life in unnotched and three kinds of notched 2024-T4 aluminum alloy specimens. Carefully designed fatigue tests under a constant temperature and humidity condition provided fatigue life distributions over a wide range of stress amplitude. This study used about 1000 specimens. On the basis of the test results, the dependence of the scatter in fatigue life on notch configuration, the period to crack initiation, the level of stress amplitude, the median fatigue life, and the slope of the median S-N curve is investigated, and the relationship between the distributional form of fatigue life and the shape of the median S-N curve is discussed. It is concluded that the slope and shape of the median S-N curve in the vicinity of the test stress level are closely related to the scatter and distributional form of fatigue life respectively. This is common to the unnotched and three kinds of notched specimens. A variability hypothesis to correlate the median S-N curve with fatigue life distributions is examined.

scholarly journals Ukraine in the history of the movement for the conservation of geological heritage in Europe

2020 ◽  
Vol 29 (1) ◽  
pp. 111-134
Author(s):  
Volodymyr V. Manyuk ◽  
Olesia V. Bondar ◽  
Oleh V. Yaholnyk
Keyword(s):  
Political System ◽  
Nature Reserve ◽  
Geological Structure ◽  
Geological Heritage ◽  
History Of ◽  
The Subject ◽  
Relationship Of ◽  
The Relationship ◽  
First Nature

The paper focuses on the history of the movement for preservation of geological heritage of Ukraine, closely related to the history of geoconservation in Europe; determines the relationship of the extent of geodiversity and geological structure of a certain country, political system, historical traditions and attitude towards wildlife and inanimate nature. Despite the fact that geodiversity and biodiversity have always been in parallel, traditionally all nations in all the continents have focused more on the preservation of so-called wildlife. The article describes that preservation of the so-called inanimate nature; provides a rather sufficient analysis of literature sources which report on the problem of preserving bio- and geodiversity not only in Ukraine, but also in other countries of Europe. In particular, the combination of biotic and abiotic constituents of nature proved to be an essential aspect in determining the place of the world`s first nature reserve and location of an important centre of Buddhism in Mihintale, Sri Lanka. The start of the movement for preservation of so-called inanimate nature in Europe could, with a certain extent of possibility, be considered the first historical written mention of the subject, which was declared in the 10th Chapter of Third Statute of Lithuania in 1588. That is protection of rivers against artificial change of their banks, change in currents and preservation of large erratic boulders. As an important stage of the beginning of the movement for preservation of the so-called inanimate, can be considered the year 1668, when in Germany the Baumannshöhle cave was preserved. It was first mentioned in the literature in 1565, and in 1646 the cave became an object of tourism. During the analysis of the historical stage related to the movement ProGEO, we emphasizes international events in which the representatives of the Ukrainian ProGEO group took part. Active work of the Ukrainian ProGEO group created conditions for transition to a new level of geoconservation, i.e. determination of the possibility of creating a new category of objects of the Nature-Reserve fund of Ukraine – geological parks (geoparks) as important locations for the development of geotourism and territories of complex conservation of the natural environment.

scholarly journals Suicide in secure psychiatric facilities

2002 ◽  
Vol 8 (6) ◽  
pp. 408-417 ◽  
Author(s):  
Harvey Gordon
Keyword(s):  
Mental Health ◽  
Potential Hazard ◽  
Time Of Death ◽  
Mental Health Legislation ◽  
Self Harm ◽  
Harm To Others ◽  
The Subject ◽  
Health Legislation ◽  
The Relationship

Suicide may be defined as intentional self-killing, although the definition has been the subject of critical review (Fairbairn, 1995). As the determination of whether intent was present at the time of death by suicide can be difficult, coroner's inquests tend to underestimate the number of suicides. At the time of suicide, the vast majority of people are suffering from some form of mental disorder, although there may, exceptionally, be a few rational suicides. Suicide is a relatively uncommon event, but the possibility of suicide by those with mental disorders is always a potential hazard faced by health and allied professionals responsible for their care. Detention of a patient in hospital under mental health legislation is often precipitated by concern regarding risk of self-harm and/or risk of harm to others and potential for absconding and, at times, admission to a locked or secure facility is necessary. Detained patients in secure facilities include both offender patients, admitted through the courts or transferred during sentence from prison, and patients on civil orders under sections 2 or 3 of the Mental Health Act 1983. The relationship between suicidal behaviour and that which is violent or homicidal is complex but relevant to an understanding of the phenomenon of suicide in secure conditions.

HUBUNGAN ANTARA BELAJAR BERDASAR REGULASI DIRI DENGAN SIKAP TERHADAP EKSTRAKURIKULER PADA SISWA KELAS XI SMA MARDISISWA SEMARANG

2019 ◽  
Vol 4 (2) ◽  
pp. 30-35
Author(s):  
Randwitya Ayu Ganis Hemasti
Keyword(s):  
Extracurricular Activities ◽  
Self Regulation ◽  
Coefficient Of Determination ◽  
Religious Institutions ◽  
Test Results ◽  
Significance Level ◽  
Emotional Factors ◽  
The Relationship ◽  
Effective Contribution

This study aimed to determine the relationship between learning based on self-regulation with attitudes toward extracurricular activities, and to determine the effective contribution of learning based on self-regulation. The population in accordance with the characteristics in this study amounted to 113 students in Mardisiswa Semarang High School. Data collection uses a scale of learning based on self-regulation consisting of 31 items (α = 0.939), and a scale of attitude towards extracurricular consisting of 30 items (α = 0.970). The results of hypothesis testing show that learning based on self-regulation is positively related to attitudes towards extracurricular activities indicated by rxy = 0.529 with a significance level of correlation of 0,000 (p <0.05). The test results obtained coefficient of determination of 0, 280. It means that learning based on student self-regulation gives an effect of 28% on attitudes toward extracurricular. While 72% of attitudes towards extracurricular are influenced by other factors outside the variables of this study. These factors include personal experience, the influence of others who are considered important, the influence of culture, mass media, religious institutions, and the influence of emotional factors.   Keywords: self-regulation, Extracurricular.   Penelitian ini ditujukan untuk mengetahui hubungan antara belajar berdasar regulasi diri dengan sikap terhadap ekstrakurikuler, dan untuk mengetahui sumbangan efektif belajar berdasar regulasi diri. Populasi yang sesuai dengan karakteristik dalam penelitian ini berjumlah 113 siswa di SMA Mardisiswa Semarang. Pengumpulan data menggunakan skala belajar berdasar regulasi diri yang terdiri dari 31 item (α = 0,939), dan skala sikap terhadap ekstrakurikuler yang terdiri dari 30 item (α = 0,970).Hasil pengujian hipotesis menunjukkan bahwa belajar berdasar regulasi diri berhubungan secara positif dengan sikap terhadap ekstrakurikuler yang ditunjukkan dengan rxy= 0,529 dengan tingkat signifikansi korelasi sebesar 0,000 (p<0,05). Hasil pengujian diperoleh nilai koefisiensi determinasi sebesar 0, 280. Artinya adalah belajar berdasar regulasi diri siswa memberikan pengaruh sebesar 28% terhadap sikap terhadap ekstrakurikuler. Sedangkan 72% sikap terhadap ekstrakurikuler dipengaruhi oleh faktor-faktor lain di luar variabel penelitian ini. Faktor- faktor tersebut antara lain adalah pengalaman pribadi, pengaruh orang lain yang dianggap penting, pengaruh kebudayaan, media massa, lembaga agama, dan pengaruh faktor emosional   Kata kunci: Regulasi Diri, Ekstrakurikuler

Kunstgeschichte

2008 ◽  
Keyword(s):  
Current Literature ◽  
Art History ◽  
Seventh Edition ◽  
Standard Work ◽  
The Subject ◽  
The Relationship

The standard work for students and teachers of art history: a determination of the subject of the field is followed by a presentation of the means and methods of the art historian and finally a look at the relationship to the neighbouring disciplines. With numerous further references and reading tips the volume is more than just an "introduction" into the subject for art history students. For this seventh edition all articles were reviewed, some revised and updated with current literature references.

An Overview of the Fatigue of Polychloroprene Rubber

2014 ◽  
Vol 891-892 ◽  
pp. 518-523
Author(s):  
Jean Louis Poisson ◽  
Florian Lacroix ◽  
Stéphane Méo ◽  
Gaelle Berton ◽  
Narayanaswami Ranganathan
Keyword(s):  
Fatigue Behavior ◽  
Viscoelastic Behavior ◽  
Fatigue Tests ◽  
Test Results ◽  
Biaxial Fatigue ◽  
Synthetic Rubber ◽  
Strain Induced Crystallization ◽  
Life Enhancement ◽  
Induced Crystallization

Some fundamental studies carried in a synthetic rubber - Chloroprene CR29 are presented in the first part of the paper. A critical analysis of test results, shows that an energy based approach permits the determination of fatigue lives in this material. This aspect is further enhanced by biaxial fatigue tests in the same material. These tests covering a life range from 10000 to 1000000 cycles show that the energy based model is very efficient to describe the fatigue behavior. Some evidence of strain induced crystallization (previously observed in natural rubber) with associated life enhancement at high load ratios is also presented. A comprehensive model based on the determination of the constitutive laws taking into account the viscoelastic behavior is developed showing excellent correlation with experimental data.

scholarly journals Studies in the secretion of the pancreas and salivary glands

1933 ◽  
Vol 114 (786) ◽  
pp. 20-47 ◽  
Keyword(s):  
Golgi Apparatus ◽  
Salivary Glands ◽  
Morphological Study ◽  
Cell Activity ◽  
Neutral Red ◽  
Gland Cells ◽  
The Subject ◽  
The Relationship

In recent years considerable attention has been paid by various workers to the cytological constituents of various gland cells. In invertebrates lolloping the lead of Parat and Painlevé (1924), the so-called salivary glands of chironomous have been the favourite objects of study (Beams and Goldschmidt, 1930 ; Gatenby, 1932), while in vertebrates the pancreas has been more usually chosen (Parat, 1928 ; Covell, 1928 ; Ludford, 1930 ; Beams, 1930 ; Gatenby, 1931). The chief object of these researches has been to discover what relationship, if any, exists between the Golgi apparatus and the cell bodies revealed by intravitam staining with neutral red (so-called vacuome of Parat), but the conclusions reached have been in every case conflicting. In consideration of the great diversity of opinion existing between these workers it was hoped in the present instance that a reinvestigation of the cytology of the pancreas together with the salivary glands might throw light on the subject, since the problem in each must be fundamentally the same. The objects of the present work were then:— (a) complete morphological study of the Golgi apparatus in the cells of these glands. (b) A study of the structures revealed intra-vitam by neutral red. (C) A determination of the relationship between these structures and the known cell constituents. (d) A study of the various secretory stages in the cell activity.

Test and Research to the Dank Ratio of Woven Filtering Fabric

2011 ◽  
Vol 332-334 ◽  
pp. 916-919
Author(s):  
Gui Fen Yao ◽  
Jian Hua Yin ◽  
Hai Wen Liu
Keyword(s):  
Water Permeability ◽  
Performance Indicator ◽  
Woven Fabrics ◽  
National Standards ◽  
Test Results ◽  
Quality Of Water ◽  
Relationship Of ◽  
The Relationship

No matter for clothes fabric or industry fabric, the water permeability is an important performance indicator. In order to explore relationship of the water permeability of woven filtering fabrics with the fabric structure parameters, we design sixteen fabric. According to the national standards of determination of water permeability of woven filtering fabric, we test the dank ratio of the design fabric. In this paper we analysis the water permeability and structure parameter of woven filtering fabric with test the quality of water on some time through woven fabrics. We calculated the dank ratio from the water permeable quality and other parameters. The results indicate that, the effect of fabric texture on the dank ratio of woven fabrics is that the dank ratio of the plain weave is the smallest and the satin weave is the biggest. In addition, the relationship between overall covering factor and water permeability showed that the water permeability decreases along with the overall covering factor increasing. A linear regression equation between dank ratio and overall covering factor is get from the test results. In order to get big dank ratio, we should produce fabric with satin weave and lower overall covering factor.

scholarly journals Hubungan antara Psychological Well Being dan Kepuasan Kerja pada Karyawan di Kantor X

2018 ◽  
Vol 7 (1) ◽  
pp. 39
Author(s):  
Joy Krismarwaty Tasema
Keyword(s):  
Job Satisfaction ◽  
Quantitative Methods ◽  
Well Being ◽  
Average Score ◽  
Reliability Test ◽  
Test Results ◽  
Earned Value ◽  
Psychological Well Being ◽  
The Subject ◽  
The Relationship

This research aims to know the relationship between psychological well being and job satisfaction by using quantitative methods with the technique of correlation of Product Moment of Carl Pearson. The hypothesis in this study is a positive correlation between psychological well being and job satisfaction on employees in Kantor X . Measuring instrument used in this study is psychological well being Scale Ryff’s (1989) with the reliability test results amounted to 0,915. The second scale of job satisfaction by Brayfield and Rothe (1951) with the reliability test results amounted to 0,825. On average psychological well being  variable subject obtain score 81,90 who belongs in the category of variable height, and job satisfaction of the average score obtained 49,25 the subject belongs in the category. Correlation analysis of product moment in earned value r = 0.632 (p < 0.05); thus there is a relationship between significant positive relationship between psychological well being and job satisfaction on employees in Kantor X.

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