scholarly journals Statistical Review of Microstructure-Property Correlation of Stainless Steel: Implication for Pre- and Post-Weld Treatment

Processes ◽  
2020 ◽  
Vol 8 (7) ◽  
pp. 811
Author(s):  
Musa Muhammed ◽  
Mazli Mustapha ◽  
Turnad Lenggo Ginta ◽  
Abdullah Musa Ali ◽  
Faizal Mustapha ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Low Cost ◽  
Dissimilar Welding ◽  
Base Metals ◽  
The Past ◽  
Treatment Processes ◽  
Property Correlation ◽  
Very High ◽  
Welding Technique ◽  
Made In

For the past three centuries, there has been a very high demand for stainless steel for different applications, due to its corrosion resistance coupled with the good strength and low cost of the metal. Several welding techniques have been adopted in the fabrication of stainless steel, with the choice of welding technique hinged on the desired requirements. Advancement has been made in its dissimilar welding with other metals like aluminum, copper and titanium. While similar welding of stainless steel faces the challenge of weld metal property deterioration, dissimilar welding poses more serious challenges due to the differential in chemical composition and the thermophysical properties of the base metals. A review of the literature reveals that considerable progress has been made in the improvement of the properties of the weld joint by the application of several weld treatment processes. It was discovered that most of the researchers focused on the effect of these weld treatment processes on the properties of the weld joints, with little attempt to establish a relationship between the microstructure and properties. This review paper critically analyzed the effect of weld treatment processes on the properties of stainless steel in light of microstructure-property correlation.

scholarly journals Moving Forward With Accelerometer-Assessed Physical Activity: Two Strategies to Ensure Meaningful, Interpretable, and Comparable Measures

2018 ◽  
Vol 30 (4) ◽  
pp. 450-456 ◽  
Author(s):  
Alex V. Rowlands
Keyword(s):  
Physical Activity ◽  
Black Box ◽  
Data Sets ◽  
Accelerometer Data ◽  
Future Health ◽  
The Past ◽  
Acceleration Data ◽  
Night And Day ◽  
Very High ◽  
Made In

Significant advances have been made in the measurement of physical activity in youth over the past decade. Monitors and protocols promote very high compliance, both night and day, and raw measures are available rather than “black box” counts. Consequently, many surveys and studies worldwide now assess children’s physical behaviors (physical activity, sedentary behavior, and sleep) objectively 24 hours a day, 7 days a week using accelerometers. The availability of raw acceleration data in many of these studies is both an opportunity and a challenge. The richness of the data lends itself to the continued development of innovative metrics, whereas the removal of proprietary outcomes offers considerable potential for comparability between data sets and harmonizing data. Using comparable physical activity outcomes could lead to improved precision and generalizability of recommendations for children’s present and future health. The author will discuss 2 strategies that he believes may help ensure comparability between studies and maximize the potential for data harmonization, thereby helping to capitalize on the growing body of accelerometer data describing children’s physical behaviors.

Long Term Unemployment: The Case for Policy Reform

1993 ◽  
Vol 4 (2) ◽  
pp. 218-240 ◽  
Author(s):  
Bruce Chapman
Keyword(s):  
Labour Market ◽  
Policy Reform ◽  
Absolute Number ◽  
Green Paper ◽  
The Past ◽  
Subsidy Scheme ◽  
Fundamental Challenge ◽  
Very High ◽  
Made In

Long term unemployment is now Australia's most difficult and costly labour market problem. This paper argues the case for a different policy reorientation to what has been followed in the past. The first conclusion is that in the absence of a substantial reorientation of policy long term unemployment will remain very high, with the absolute number staying above the level inherited from the 1982/83 recession — which was until the current recession the highest in Australian history. Second, the equity and macroefficiency costs of not doing anything radically different are argued to be very high. A final part of the analysis considers the fundamental challenge of the Job Compact policy suggestion made in the Government's Green Paper on unemployment. However, the way in which the policy is to be instituted needs attention. It is likely that the use of the current JOBSTART wage subsidy scheme will not be enough to achieve the desired outcomes.

scholarly journals A LOW-COST INSHORE WAVE DIRECTION INDICATOR

1974 ◽  
Vol 1 (14) ◽  
pp. 10
Author(s):  
G. De F. Retief ◽  
A.P.M. Vonk
Keyword(s):  
Flow Direction ◽  
Meteorological Data ◽  
Low Cost ◽  
Ocean Waves ◽  
Wave Direction ◽  
The Past ◽  
Steady State Current ◽  
Near Shore ◽  
Reliable Solution ◽  
Made In

Although many attempts have been made in the past to measure the direction of propagation of ocean waves, a need for a simple, reliable solution to the problem has remained. The technique described here, intended for near-shore usage, makes use of a simple bottom-mounted flow direction indicator. The influence of rip and longshore currents on wave direction recordings is identified and a means of reducing these steady state current effects by a reduction in gauge sensitivity is presented, along with various possible recording and analysis techniques. Usefulness of the gauge is established as a simple engineering tool with certain limitations and examples are given of »'aire direction recordings related to meteorological data. A possible usage of the gauge FE an approximate sediment transport indicator is also proposed.

scholarly journals Sustainable Agriculture: Nutrition of Indigenous American 3 Sisters Garden Compared to Monoculture Corn Production and a Cool Old Squash

2020 ◽  
pp. 99-108
Author(s):  
Patricia A. Terry ◽  
Debra Pearson ◽  
Gregory Holder
Keyword(s):  
Soil Nutrients ◽  
Low Cost ◽  
Agricultural Practices ◽  
Corn Production ◽  
The Past ◽  
Eye Health ◽  
Exciting Opportunity ◽  
Nutritional Analysis ◽  
Three Sisters ◽  
Very High

Balancing productivity, profitability, human health, and environmental health is a key challenge for agricultural sustainability. After WW2, however, U.S. government agricultural subsidies have created cheap corn that the processed food industry has infused into virtually every aspect of the American diet. As a result, rates of diabetes, heart disease, hypertension, kidney disease, obesity, and metabolic syndrome have increased significantly in the past forty years, especially among low socio-economic groups and non-Western peoples, due to the low cost of processed foods. Additionally, industrial monoculture corn production depletes soil nutrients and increases weeds and insects, requiring fertilizer and pesticide inputs that contaminant water, reduce biodiversity, and contribute to eutrophication. Multi-cropping, in particular growing corn, squash, and legumes in an Indigenous American Three Sisters garden provides significantly improved nutrition per mass of plant compared to corn. Squash is very high in carotenoids that have been shown to reduce rates of chronic diseases, such as cancers, diabetes, hypertension, and cardiovascular disease. It also promotes eye health and improves immune function. Agricultural practices of multi-cropping also replenish soil nutrients and suppress weeds and insects, requiring fewer fertilizer and pesticide inputs. Finally, in an exciting opportunity, the ancient Indigenous American squash Gete Okosomin, “Cool old squash,” was grown and a complete nutritional analysis was obtained and compared to common modern squashes. Different stories of its origin are also discussed.

scholarly journals TREND ANALYSIS OF LAND UTILIZATION IN BANGLADESH

2020 ◽  
Vol 6 (2) ◽  
pp. 39-46
Author(s):  
Shohel Rana ◽  
Omar Faruk ◽  
Najma Begum ◽  
Mimma Tabassum
Keyword(s):  
Land Use ◽  
Trend Analysis ◽  
Resource Use ◽  
Secondary Data ◽  
Land Utilization ◽  
Land Use Pattern ◽  
The Past ◽  
Very High ◽  
A Current ◽  
Made In

Due to alterations in physiographic and social-economic conditions, climatic changes, adaptation and population growth, the land utilization of Bangladesh is changing very rapidly. Small farms and landless household constitute about 80% of total area households, the majority of whom depend on agriculture for their livelihood. It is obvious that total agriculture land over the periods in the past has not increased although population has increased significantly [12]. Bangladesh is a small country but it bears a huge population, resulting in a very high density of population and very high intensity of land and resource use. Based on secondary data of Bangladesh Bureau of Statistics, an attempt has been made in this paper to evaluate the changes in land use pattern during the period of 1990 to 2015. Absolute utilization of land for different purposes during this period as well as trend values and growth rates were estimated. Trend analysis and exponential growth rate showed that forest area significantly increased by 35.93% and 0.3% per annum and land not available for cultivation is significantly decreased by 4.49% and 0.04%per annum respectively. Result also show that cultivate waste is significantly decreased at the rate of 1.1% per annum. On the other hand, a current fallow is decreased by 0.2% per annum. The trend values was found statistically significant for land use in forest and cultivate waste.

Wastewater management in Zimbabwe in the context of sustainability

Water Policy ◽  
2004 ◽  
Vol 6 (6) ◽  
pp. 501-517 ◽  
Author(s):  
Innocent Nhapi ◽  
Huub J. Gijzen
Keyword(s):  
Paradigm Shift ◽  
Low Cost ◽  
Institutional Arrangements ◽  
Wastewater Management ◽  
Environmental Implications ◽  
Satisfactory Solution ◽  
The Past ◽  
Funding Mechanism ◽  
Natural Treatment ◽  
Made In

Conventional sanitation approaches are rather inappropriate and expensive ways of providing a satisfactory solution to increasing wastewater problems in developing countries. This paper looks at the financial and environmental implications of the sanitation approaches adopted in Zimbabwe, and from the weaknesses identified, suggests a paradigm shift in which wastewater treatment is geared towards resource recovery and reuse. It was observed that unsustainable methods continue to be used because of deficient institutional arrangements and irrational technology choices made in the past. Natural treatment methods were recommended because they are low cost, easy to operate and maintain, and allow for the re-use of effluent. To achieve this requires a responsive institutional and funding mechanism backed by realistic legislation.

EFFECT OF FILLER METALS ON THE MECHANICAL PROPERTIES OF DISSIMILAR WELDING OF STAINLESS STEEL 316L AND CARBON STEEL A516 GR 70

2015 ◽  
Vol 75 (7) ◽  
Author(s):  
Abdollah Bahador ◽  
Esah Hamzah ◽  
Mohd Fauzi Mamat
Keyword(s):  
Tensile Strength ◽  
Stainless Steel ◽  
Carbon Steel ◽  
Weld Metal ◽  
Dissimilar Welding ◽  
Hardness Profile ◽  
Base Metals ◽  
Stainless Steel 316L ◽  
Sharp Drop ◽  
Filler Metals

This paper describes an investigation on the effect of using three different filler metals to weld two dissimilar metals namely, stainless steel 316L and low alloy carbon steel A516 gr 70. Manual Gas Tungsten Arc welding (GTAW) with three filler metals including ER 80S-Ni1, ER309L, ER NiCrMo-3 were selected to weld the two metals. Radiography and penetrant tests were performed on the welded metals to ensure the surface and internal soundness of the welds based on the tensile tests results, all the specimens failed at the carbon steel A516 gr 70 base metals with fully ductile fracture mode (cup and cone). Welded samples using Inconel 615 filler metal has the highest strength of 512 MPa while other samples show almost similar strength of 481 and 487 MPa. The tensile strength of all the welded samples is found to be in between the tensile strength of the base metals. Micro-hardness test showed that ER80S-Ni1weld has the highest hardness, meanwhile hardness profile of ER309L presented a sharp drop in the stainless steel side and ER NiCrMo-3 weld metal illustrated hardness above the two base metals with fewer variations across the weld metal.

Aerodynamic Analysis Using CFD for Gas Turbine Combustion Chamber

2007 ◽  
Author(s):  
Lucilene O. Rodrigues ◽  
Harley S. Alencar ◽  
Marco A. R. Nascimento ◽  
Osvaldo J. Venturini
Keyword(s):  
Numerical Simulation ◽  
Combustion Chamber ◽  
Low Cost ◽  
Turbulence Models ◽  
Combustion Chambers ◽  
Aerodynamic Analysis ◽  
The Past ◽  
Satisfactory Precision ◽  
Low Nox Emission ◽  
Made In

In the past few years, with the development of advanced numerical computational codes, numerical simulation became a promising option to developing and improving the technology in different fields. The obtained results by simulations are used to get important information during the design phase or optimization of industrial equipment. Its employment generates reliable results at low cost due to the reduced number of experiments as well as the opportunity to develop new products and perform many simulations before its production. However, the numerical simulation credibility can only be verified when compared to the obtained results by experiments. This work aims to present and evaluate different aerodynamics models applied to combustion chambers using a CFD tool. In addition, aerodynamic analysis is made in a model of combustion chamber, where the flow is simulated with successive refining of the mesh as part of its validation process. For it, it is used a Low Nox Emission Combustion Chamber from Floxcom project as reference to validate turbulence models. Once that it is done, the selected turbulence model with satisfactory precision is used to describe the aerodynamic behavior of an annular combustion chamber from velocity and pressure distribution, which are important parameters to set load losses and recirculation intensity, which can affect the complex phenomenon of combustion.

scholarly journals Hyperloop Academic Research: A Systematic Review and a Taxonomy of Issues

2021 ◽  
Vol 11 (13) ◽  
pp. 5951
Author(s):  
Konstantinos Gkoumas
Keyword(s):  
Systematic Review ◽  
High Speed ◽  
Academic Research ◽  
The Past ◽  
The Status ◽  
Substantial Progress ◽  
Scopus Database ◽  
Modern Form ◽  
Very High ◽  
Made In

Hyperloop is a proposed very high-speed ground transportation system for both passenger and freight that has the potential to be revolutionary, and which has attracted much attention in the last few years. The concept was introduced in its modern form relatively recently, yet substantial progress has been made in the past years, with research and development taking place globally, from several Hyperloop companies and academics. This study examined the status of Hyperloop development and identified issues and challenges by means of a systematic review that analyzed 157 documents from the Scopus database on Hyperloop since 2014. Following that, a taxonomy of topics from scientific research was built under different physical and operational clusters. The findings could be of help to transportation academics and professionals who are interested in the developments in the field, and form the basis for policy decisions for the future implementation of Hyperloop.

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