scholarly journals A comparative study of the cooling-rate effect on rock strength reduction after microwave irradiation

2020 ◽  
Vol 1 ◽  
Author(s):  
Hamed Rafezi ◽  
Samir M. Deyab ◽  
Ferri Hassani ◽  
Seyed Ali Ghoreishi-Madiseh
Keyword(s):  
Cooling Rate ◽  
Rock Strength ◽  
Cutting Tools ◽  
Economic Benefits ◽  
Strength Reduction ◽  
Brazilian Tensile Strength ◽  
The Past ◽  
Mcgill University ◽  
Rock Mechanical Properties ◽  
Excavation Performance

AbstractA variety of machines are currently being used for mechanical excavation in mining and civil industries. A series of research works have been conducted at McGill University in the past decade to study the effects of microwave (MW) irradiation on rock mechanical properties. The idea is to enhance the excavation performance by improving the rate of penetration and decreasing the wear rate on the cutting tools. These two effects would eventually translate into economic benefits for mine operators. The effectiveness of MW on weakening rocks is proven, however the most efficient method to employ MW in mines is still under investigation. This article presents some experimental results on the effects of cooling- rate on rock strength. Brazilian Tensile Strength (BTS) of microwave treated samples were compared in natural air-cooled and water rapid-cooled conditions.

scholarly journals Sakurai’s Object: Constraints from its Variability?

1998 ◽  
Vol 11 (1) ◽  
pp. 360-360
Author(s):  
T. Gautschy ◽  
H.W. Duerbeck ◽  
A.M. Van Genderen ◽  
S. Benetti
Keyword(s):  
Cooling Rate ◽  
Nuclear Energy ◽  
Stability Analyses ◽  
The Past ◽  
Stellar Pulsations ◽  
First Results ◽  
Effective Temperatures ◽  
Stellar Envelopes ◽  
Light Variability ◽  
Hr Diagram

The peculiar outburst of the star baptized Sakurai’s Object (SO) is a conceivable example of a late He shell flash in a post-AGB object. The new source of nuclear energy forces such objects toward high luminosities and eventually low effective temperatures; they cross the HR diagram in a comparable fashion as FG Sge did in the past - i.e., they move noticeably on the HR diagram on human timescales. From monitoring campaigns of SO during the last year, first estimates of its cooling rate were derived and in particular cyclic light variability was established. We present first results from attempts to model stellar envelopes appropriate for SO. As we hypothesize the light variability to be attributable to stellar pulsations, we aim at constraining the basic stellar parameters based on stability analyses of our envelope models. Radial, nonadiabatic stability computations provided predictions of the modal content which should be observable as SO evolves. The particular components in such mode spectra of SO as they are to appear in the coming years should indeed help to constrain basic stellar parameters such as mass and luminosity.

Integration of Chemofacies and Rock Mechanical Properties Using Machine Learning Algorithms: Implications for Geomechanics and Hydraulic Fracture Stimulations in Paleozoic Formations, Saudi Arabia

2021 ◽  
Author(s):  
Maaruf Hussain ◽  
Abduljamiu Amao ◽  
Khalid Al-Ramadan ◽  
Sunday Olatunji ◽  
Ardiansyah Negara
Keyword(s):  
Machine Learning ◽  
Mechanical Properties ◽  
Saudi Arabia ◽  
Spatial Distribution ◽  
Chemical Composition ◽  
Rock Strength ◽  
Machine Learning Algorithms ◽  
Unconventional Reservoirs ◽  
Geochemical Properties ◽  
Rock Mechanical Properties

Abstract The knowledge of rock mechanical properties is critical to reducing drilling risk and maximizing well and reservoir productivity. Rock chemical composition, their spatial distribution, and porosity significantly influenced these properties. However, low porosity characterized unconventional reservoirs as such, geochemical properties considerably control their mechanical behavior. In this study, we used chemostratigraphy as a correlation tool to separate strata in highly homogenous formations where other traditional stratigraphic methods failed. In addition, we integrated the chemofacies output and reduced Young's modulus to outline predictable associations between facies and mechanical properties. Thus, providing better understanding of lithofacies-controlled changes in rock strength that are useful inputs for geomechanical models and completions stimulations.

The Optimization of Typical Environmental Issues by LINGO Software

2014 ◽  
Vol 1010-1012 ◽  
pp. 1985-1988
Author(s):  
Min Li ◽  
Bao You Liu
Keyword(s):  
Environmental Monitoring ◽  
Environmental Issues ◽  
Economic Benefits ◽  
Environmental Benefits ◽  
Resources Allocation ◽  
Running Speed ◽  
The Past ◽  
Valid Result

LINGO software with many favorable features such as convenient operation, high running speed, wide application and valid result, has been widely used in solving complicated issues in environmental fields in the past a few years. In this paper, three practical examples in environmental monitoring were introduced and resolved by LINGO software, the reliability of the results was verified and the comparison with other methods was given. The results show that, LINGO software is useful to direct funds and resources’ allocation in environmental monitoring, and it is an effective tool to improve economic benefits and obtain better environmental benefits.

The Theory Behind the Economic Role of Managing the Strategic Alignment of Organizations while Creating New Markets

2003 ◽  
pp. 69-94
Author(s):  
Sam Lubbe
Keyword(s):  
Economic Impact ◽  
Strategic Alignment ◽  
Economic Benefits ◽  
Telecommunication Networks ◽  
The Internet ◽  
New Markets ◽  
Economic Role ◽  
Market Structures ◽  
The Past

Over the past couple of years, the Internet has taken off and organizations will soon reap economic benefits on it. E-commerce will therefore hopefully emerge as an efficient yet effective mode of creating new markets although most managers still doubt the economic impact and profitability it has. Enabled by global telecommunication networks and the convergence of computing, telecom, entertainment and publishing industries, e-commerce is supplanting (maybe replacing) traditional commerce. In the process, it is creating new economic opportunities for today’s businesses, creating new market structures. Managers of tomorrow must therefore understand what e-commerce is; how the approach to this concept will be; and how it will affect the economic position of the organization.

scholarly journals Hydrogen-assisted cracking in GMA welding of high-strength structural steels using the modified spray arc process

2020 ◽  
Vol 64 (12) ◽  
pp. 1997-2009
Author(s):  
Thomas Schaupp ◽  
Michael Rhode ◽  
Hamza Yahyaoui ◽  
Thomas Kannengiesser
Keyword(s):  
Weld Metal ◽  
Gma Welding ◽  
High Strength ◽  
Economic Benefits ◽  
Structural Steels ◽  
Test Series ◽  
Deposition Rates ◽  
The Past ◽  
Hydrogen Assisted Cracking ◽  
Implant Test

Abstract High-strength structural steels are used in machine, steel, and crane construction with yield strength up to 960 MPa. However, welding of these steels requires profound knowledge of three factors in terms of avoidance of hydrogen-assisted cracking (HAC): the interaction of microstructure, local stress/strain, and local hydrogen concentration. In addition to the three main factors, the used arc process is also important for the performance of the welded joint. In the past, the conventional transitional arc process (Conv. A) was mainly used for welding of high-strength steel grades. In the past decade, the so-called modified spray arc process (Mod. SA) has been increasingly used for welding production. This modified process enables reduced seam opening angles with increased deposition rates compared with the Conv. A. Economic benefits of using this arc type are a reduction of necessary weld beads and required filler material. In the present study, the susceptibility to HAC in the heat-affected zone (HAZ) of the high-strength structural steel S960QL was investigated with the externally loaded implant test. For that purpose, both Conv. A and Mod. SA were used with same heat input at different deposition rates. Both conducted test series showed same embrittlement index “EI” of 0.21 at diffusible hydrogen concentrations of 1.3 to 1.6 ml/100 g of arc weld metal. The fracture occurred in the HAZ or in the weld metal (WM). However, the test series with Mod. SA showed a significant extension of the time to failure of several hours compared with tests carried out with Conv. A.

scholarly journals Intensive Short-term Dynamic Psychotherapy: A Treatment Overview and Empirical Basis

2013 ◽  
Vol 16 (1) ◽  
pp. 6-15 ◽  
Author(s):  
Allan Abbass ◽  
Joel M. Town ◽  
Ellen Driessen
Keyword(s):  
Therapeutic Process ◽  
Short Term ◽  
The Unconscious ◽  
Dynamic Psychotherapy ◽  
Main Research ◽  
The Core ◽  
The Past ◽  
Character Structure ◽  
Mcgill University ◽  
Research Findings

Based on over forty years of videotaped case-based research, Habib Davanloo of McGill University, Canada, discovered some of the core ingredients that can enable direct and rapid access to the unconscious in resistant3 patients, patients with func-tional disorders, and patients with fragile character structure. We will describe here some of the main research findings that culminated in his description of a central therapeutic process involved in the intensive short-term dynamic psychotherapy (ISTDP) model. We will also describe the evolution of the technique over the past thirty years and summarize the empirical base for Davanloo’s ISTDP.

Foundations of Rights Jurisprudence in Israel: Chief Justice Agranat's Legacy

1990 ◽  
Vol 24 (2) ◽  
pp. 211-269 ◽  
Author(s):  
Pnina Lahav
Keyword(s):  
Sovereign State ◽  
The Past ◽  
Chief Justice ◽  
British Rule ◽  
The Future ◽  
Mcgill University ◽  
The Individual ◽  
The University ◽  
Distinguished Member

“Liberty of the individual is a thing of the past, or the future, in Palestine”, wrote Bernard Joseph, a distinguished member of Israel's “government in the making” in 1948, shortly before Israel was inaugurated as a sovereign state. Joseph's “present” was the dusk of British rule in Palestine. Draconian Defence (Emergency) Regulations suspended conventional liberties ordinary westerners were accustomed to expect and turned Palestine into a police state.Precisely what “liberty of the individual” the esteemed jurist, who held degrees from both McGill University and the University of London, had in mind when he invoked the past of Palestine is not entirely clear. He could not have possibly meant liberty under the Ottoman regime which prevailed until 1918. Ottoman rule in Palestine was authoritarian, feudal and corrupt.

The Measurement of Errors in Gears for Turbine Reduction Drives

1947 ◽  
Vol 157 (1) ◽  
pp. 418-451 ◽  
Author(s):  
C. Timms
Keyword(s):  
Cutting Tools ◽  
National Physical Laboratory ◽  
The Past ◽  
Gear Cutting ◽  
Physical Laboratory ◽  
Gear Hobbing ◽  
Portable Instruments ◽  
The Relationship

The paper forms a review of the work carried out during the past six years at the National Physical Laboratory in connexion with the development of methods for measuring the errors of large gears for turbine reduction drives by means of a series of portable instruments. The relationship between these errors and the inaccuracies of gear-hobbing machines and gear-cutting hobs is discussed. Methods of determining these inaccuracies are described, together with information showing the improvements which have taken place in the accuracy of these machines and cutting tools resulting from the applications of the methods of testing.

Iran's Rouhani could take up his mentor’s mantle

2017 ◽  
Keyword(s):  
Political Power ◽  
Gulf Cooperation Council ◽  
Economic Benefits ◽  
The West ◽  
Content Type ◽  
The Past ◽  
Political Landscape ◽  
Political Factions

Significance Rafsanjani, who had lost much overt political power over the past decade, was an important behind-the-scenes power broker in a deeply divided political landscape. He supported President Hassan Rouhani and centrist and reformist political factions. He was also an ardent advocate of economic liberalisation and Iranian rapprochement with the West. Impacts Economic benefits from the nuclear deal will be key to Rouhani’s reconnection with his political base. Rafsanjani's death could trigger a hard-line reaction that could boost tensions with the Gulf Cooperation Council countries. If 77-year-old Khamenei were also to pass away, regime instability might increase.

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