scholarly journals Technology of composite erosion-radiation coating

2017 ◽  
Vol 2 (9) ◽  
pp. 9-16
Author(s):  
Владислав Смоленцев ◽  
Vladislav Smolentsev ◽  
Михаил Кондратьев ◽  
Mihail Kondratiev ◽  
Евгений Смоленцев ◽  
...  
Keyword(s):  
Surface Profile ◽  
Thick Layer ◽  
Plasma Beam ◽  
Simultaneous Impact ◽  
Profile Matching ◽  
Coating Formation ◽  
Process Behavior ◽  
The Impact ◽  
Manufacturing Science ◽  
A Current

A new method of composite treatment with the simultaneous impact of thermal energy of a current pulse and heat supply of a plasma beam is developed. The mechanism of a qualitative coating formation is shown at which the thick layer shaping with the improved micro-profile is achieved, where a micro-surface profile matching is achieved at the expense of the impact of concentrated energy supplied by a plasma beam to the surface of a molten coating causing an increased metal castability, its runoff from lugs into hollows and micro-irregularity height decrease. A mechanism of combined process behavior is developed which allowed creating a procedure of the design of technological modes, defining their place in technological transitions and substantiating maximum accessible technological potentialities of the method offered at the realization of working matters for science intensive products. The examples of the efficient use of a combined erosion-beam plasma treatment are shown, which extends a field of the method application and lightens a technological pre-production at the introduction into manufacturing science intensive products of new engineering generations.

scholarly journals The Surface Condition of Ni-Cr after SiC Abrasive Blasting for Applications in Ceramic Restorations

Materials ◽  
2020 ◽  
Vol 13 (24) ◽  
pp. 5824
Author(s):  
Weronika Czepułkowska-Pawlak ◽  
Emilia Wołowiec-Korecka ◽  
Leszek Klimek
Keyword(s):  
Surface Condition ◽  
Abrasive Particle ◽  
Surface Profile ◽  
Abrasive Particles ◽  
Dental Restorations ◽  
Large Width ◽  
Ceramic Restorations ◽  
The Impact ◽  
Abrasive Size ◽  
Abrasive Blasting

Abrasive blasting is a process widely used in dentistry. One of the uses is the development of metal surfaces for connections with ceramics in fixed prosthetic restorations. The purpose of this paper was to check how the rough surface profile (width, height, and depth on unevenness) impacts the surface’s condition, like its wettability and percentage of stuck abrasives. The Ni-Cr alloy surface was abrasive blasted by silicon carbide with the various pressure parameters (0.2, 0.4, and 0.6 MPa) and abrasive particle sizes (50, 110, and 250 µm). Cleaned surfaces were examined for roughness, wettability, and percentage of stuck abrasive particles on the surface. The surface after abrasive blasting using 110 µm of abrasive size and 0.4 MPa pressure has the best wettability results. The width of unevenness may cause it. When the unevenness has too small or too large width and depth, the fluids may not cover the entire cavities because of locking the air. The surface condition of dental alloys directly affects metal–ceramic connection strength. The knowledge about the impact of the abrasive blasting parameters on the bond strength will allow one to create durable dental restorations.

A New Cam-follower Safety Joint Mechanism Design based on Variable-length Four-bar Linkage for Robot Safety

2021 ◽  
pp. 1-24
Author(s):  
Seung Guk Baek ◽  
Hyungpil Moon ◽  
Hyouk Ryeol Choi ◽  
Ja Choon Koo
Keyword(s):  
Load Transfer ◽  
Impact Damage ◽  
Surface Profile ◽  
Length Change ◽  
Variable Length ◽  
Core Element ◽  
Nonlinear Load ◽  
Cam Follower ◽  
Joint Mechanism ◽  
The Impact

Abstract Humans come into physical contacts with various machines such as robots in daily life. This leads to the underlying issue of guaranteeing safety during such human-robot interactions. Thus, many devices and methods have been studied for impact damage reduction. A safety joint mechanism (SJM) using four-bar linkages has been highlighted as an impact cutoff device owing to its capabilities of nonlinear load transfer. This paper focuses on a new design and testing for a kinematic element of an SJM based on four-bar linkages to improve the impact cutoff performances. In the present work, a set of variable-length floating link designs is proposed, and the mechanism is implemented by mechanical contact surface profile shaping between the cams and followers. The performance of the cam-follower mechanism is evaluated depending on the variable length of the floating link, by using equivalent stiffness method, which successfully quantifies the performance of the proposed mechanism. Based on this design and analysis, two SJMs having symmetrical arrangements for four numbers of cam-follower mechanisms are fabricated: one SJM has fixed-length floating links and the other has variable-length floating links. The effect of the new kinematic elements on the performance improvement is verified by comparing the absorbed impact rates of the two SJMs by impact hammer-like drop tests. Consequently, it is confirmed that the rapid length change of the floating link is the core element for improving the performance of the safety mechanism.

scholarly journals Fertilizer distribution flows and logistic costs in Brazil: changes and benefits arising from investments in port terminals

2018 ◽  
Vol 21 (3) ◽  
pp. 407-422 ◽  
Author(s):  
Débora da Costa Simões ◽  
José Vicente Caixeta-Filho ◽  
Udatta S. Palekar
Keyword(s):  
Linear Programming ◽  
Programming Model ◽  
Mato Grosso ◽  
Port Development ◽  
Full Capacity ◽  
Port System ◽  
Infrastructure Investments ◽  
Port Infrastructure ◽  
The Impact ◽  
A Current

This study analyzes the impact of anticipated investments to alter Brazilian port infrastructure on fertilizer flows and fertilizer transportation logistics costs using a linear programming model designed for the task. The most notable among these investments are directed toward accelerating port development in Brazil’s “Northern-Arc”, thereby increasing fertilizer supply to new markets opening throughout the country’s expanding agricultural frontier, particularly in northern Mato Grosso state, while increasing supply to existing markets. Results from model runs show that the anticipated port infrastructure investments should ensure nationwide fertilizer logistics savings of US$ 845 million over the 2017 through 2025 period. Although these estimated benefits are outstanding, the study indicates that further expansion of Brazil’s port system, particularly in the Northern-Arc, presents additional opportunities. Model projections were that in 2025, after all planned infrastructure improvements are operational, port terminals will be near full capacity, which should make planning for future projects a current priority.

scholarly journals Modeling Asymmetry of a Current–Voltage Curve of a Novel MF-4SC/PTMSP Bilayer Membrane

Membranes ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 22
Author(s):  
Anatoly N. Filippov ◽  
Natalia A. Kononenko ◽  
Natalia V. Loza ◽  
Daria A. Petrova
Keyword(s):  
Good Accuracy ◽  
Thick Layer ◽  
Physicochemical Characteristics ◽  
Porous Membrane ◽  
Bilayer Membrane ◽  
Voltage Curve ◽  
Current Voltage ◽  
Current Voltage Curve ◽  
Exchange Membrane ◽  
A Current

A novel bilayer cation-exchange membrane—consisting of a thick layer of a pristine perfluorinated membrane MF-4SC (Russian equivalent of Nafion®-117) and a thinner layer (1 μm) of the membrane, on a base of glassy polymer of internal microporosity poly(1-trimethylsilyl-1-propyne) (PTMSP)—was prepared and characterized. Using the physicochemical characteristics of one-layer membranes MF-4SC and PTMSP in 0.05 M HCl and NaCl solutions, the asymmetric current–voltage curves (CVC) of the bilayer composite were described with good accuracy up to the overlimiting regime, based on the “fine-porous membrane” model. The MF-4SC/PTMSP bilayer composite has a significant asymmetry of CVC that is promising for using it in electromembrane devices, such as membrane detectors, sensors, and diodes.

scholarly journals Fluoride removal using electrocoagulation technique

2021 ◽  
Vol 877 (1) ◽  
pp. 012047
Author(s):  
Hind M. Ewadh ◽  
Mustafa J. Al Imari ◽  
Sabrean F. Jawad ◽  
Hayfaa A. Mubarak
Keyword(s):  
Severe Disease ◽  
Electrical Current ◽  
Electrode Spacing ◽  
Polluted Water ◽  
Fluoride Removal ◽  
Acidic Environment ◽  
Current Electrode ◽  
The Past ◽  
The Impact ◽  
A Current

Abstract A modest quantity of fluoride can increase the mineralization of teeth and reduce their cavities. But the presomerence of fluoride in excess in water can lead to severe disease infertility. In the past few decades, scientists have thus been preoccupied with developing ways to reduce sewage fluoride concentrations and reduce their effects on human health. The present study is aimed at using the technology of electrocoagulation to remove fluoride from polluted water. Tests have been done to examine the elimination of fluoride with a rectangular electrocoagulation cell and examine the impact of the experimental aspects on fluoride extraction, specifically electrical current, electrode spacing, and pH. The authors found that 93% of the fluoride has been extracted using 5mm spaced electrodes with a current density of 2 mA/cm2 and a level of pH of 7 from the polluted water after 20 min of processing. Experimental factors considerably impact the efficacy of fluoride removal. In the acidic environment, greater effectiveness of fluoride removal is being attained. The elimination effectiveness depends directly on the electric current, whereas the distance between poles is adversely linked to fluoride elimination.

Integration of Manufacturing, Science and Education as a Basis for the Re-Industrialization of Russia

2015 ◽  
pp. 94-104
Author(s):  
S. Bodrunov
Keyword(s):  
Economic Policy ◽  
Import Substitution ◽  
Domestic Industry ◽  
Technological Basis ◽  
Russian Economy ◽  
World Economic ◽  
Science And Education ◽  
The Government ◽  
The Impact ◽  
Manufacturing Science

The article investigates the problems that Russian industry has encountered during the period of economic reforms. The author explores the reasons for the competitiveness decrease and contradictions that hinder the modernization of the domestic industry. Based on the analysis the principal concept is posed of the need in the implementation of the strategy of re-industrialization in Russia on a new technological basis. The basic directions of re-industrialization, the mechanisms of its implementation, as well as the impact on import substitution are considered. Substantial attention is paid to the risks inherent in a re-industrialization of Russia and the ways to overcome them. In recent years, geo-political and geo-economic challenges to the Russian economy and society greatly exacerbated the contradictions that emerged in the previous decades of economic evolution. During a long period of time the country tried to implement an economic policy intended, in principle, at achieving the strategic goal of creating a modern socially-oriented market economy on the base of modernization. However, the practical tools for implementation of this course – first of all, the ideology of “market fundamentalism” combined with the remaining powerful black market and “hand steering” by the government – caused stagnation and further de-industrialization of the country with inevitably negative implications for the manufacturing, science, education, human capital. Most recently, the Russian economy faced additional problems, namely, the Western sanctions, world economic slump and decline in world oil prices. That is why significant changes in the objectives and tools of economic policy are so urgent.

The impact of relative CEO compensation on not-for-profit contributions

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Stacey Kaden ◽  
Gary Peters ◽  
Juan Manuel Sanchez ◽  
Gary M. Fleischman
Keyword(s):  
Large Scale ◽  
Ceo Compensation ◽  
Drop Out ◽  
Content Type ◽  
For Profit ◽  
Not For Profit ◽  
Survivorship Bias ◽  
Excess Cash ◽  
The Impact ◽  
A Current

PurposeThe authors extend research suggesting that external funders reduce their contributions to not-for-profit (NFP) organizations in response to media-reported CEO compensation levels.Design/methodology/approachEmploying a maximum archival sample of 44,807 observations from US Form 990s, the authors comprehensively assess the extent that high relative NFP CEO compensation is associated with decreases in future contributions.FindingsThe authors find that donors and grantors react negatively to high relative CEO compensation but do not react adversely to high absolute executive compensation. Contributors seem to take issue with CEO compensation when they perceive it absorbs a relatively large portion of the organizations’ total expenses, which may hinder the NFP’s mission. Additional findings suggest that excess cash held by the NFP significantly exacerbates the negative baseline relationship between future contributions and high relative CEO compensation. Finally, both individual donors and professional grantors are sensitive to cash NFP CEO compensation levels, but grantors are more sensitive to CEO noncash compensation.Research limitations/implicationsThe authors’ data are focused on larger NFP organizations, so this limits the generalizability of the study. Furthermore, survivorship bias potentially influences their time-series investigations because a current year large-scale decrease in funding due to high relative CEO compensation may cause some NFP firms to drop out of the sample the following year due to significant funding reductions.Originality/valueThe study makes three noteworthy contributions to the literature. First, the study documents that the negative association between high relative CEO compensation levels and future donor and grantor contributions is much more widespread than previous literature suggested. Second, the authors document that high relative CEO compensation levels that trigger reductions in future contributions are significantly exacerbated by excess cash held by the NFP. Finally, the authors find that more sophisticated grantors are more sensitive to noncash CEO compensation levels as compared with donors.

Human Performance Assessment to Support Rapid Prototyping and Iterative Design

1989 ◽  
Vol 33 (16) ◽  
pp. 1089-1093 ◽  
Author(s):  
James W. Broyles
Keyword(s):  
Human Performance ◽  
Operational Experience ◽  
System Operation ◽  
Training Time ◽  
Iterative Design ◽  
Performance System ◽  
Navy Personnel ◽  
The Impact ◽  
And Training ◽  
A Current

Fourteen U.S. Navy personnel with Aegis Combat System, Naval Tactical Data System (NTDS), and Non-NTDS operational experience participated in an experiment designed to investigate the impact of proposed workstation designs on operator performance, system usability, and training. Human performance data were collected on a sample of operational procedures typically performed in a Combat Information Center (CIC) for a current Navy Combat System and a prototype workstation. The prototype was developed using specific human factors design principles with the goal of reducing training time, improving operator retention of skills for system operation, reducing errors in system operation, improving operator efficiency (e.g., speed & accuracy of performance), and improving user's satisfaction with the user-computer interface. This paper reports only the preliminary results for data collected from seven subjects who performed procedures using the prototype workstation.

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