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

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.

Water Policy ◽  
2004 ◽  
Vol 6 (6) ◽  
pp. 501-517 ◽  
Author(s):  
Innocent Nhapi ◽  
Huub J. Gijzen

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.


Author(s):  
Paul C. Liu ◽  
David J. Schwab ◽  
Chin H. Wu ◽  
Keith R. MacHutchon

This paper presents a preliminary examination and analysis of a small suite of 4-D wave data to explore what new insight or inference we can garner — particularly toward the realm where conventional approaches have not been traversed. While we caught a few glimpses that might indicate a need for new conceptualizations, it by no means to negates the vast positive contributions the conventional approaches have been made in the past century. We feel it is timely to encourage further 4-D ocean wave measurement and thereby facilitate fresh new states of study and understanding of ocean waves.


Author(s):  
Lucilene O. Rodrigues ◽  
Harley S. Alencar ◽  
Marco A. R. Nascimento ◽  
Osvaldo J. Venturini

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.


2010 ◽  
Vol 662 ◽  
pp. 1-4 ◽  
Author(s):  
C. M. LINTON

Over the past forty or so years, considerable advances have been made in our understanding of the effects of ocean waves on sea ice, and vice versa, with observations, experiments and theory all playing their part. Recent years have seen the development of ever more sophisticated mathematical models designed to represent the physics more accurately and incorporate new features. What is lacking is an approach to three-dimensional scattering for ice floes that is both accurate and efficient enough to be used as a component in a theory designed to model the passage of directional wave spectra through the marginal ice zone. Bennetts & Williams (J. Fluid Mech., 2010, this issue, vol. 662, pp. 5–35) have brought together a number of solution techniques honed on simpler problems to provide just such a component.


Processes ◽  
2020 ◽  
Vol 8 (7) ◽  
pp. 811
Author(s):  
Musa Muhammed ◽  
Mazli Mustapha ◽  
Turnad Lenggo Ginta ◽  
Abdullah Musa Ali ◽  
Faizal Mustapha ◽  
...  

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.


2017 ◽  
Vol 26 (50) ◽  
pp. 115
Author(s):  
Marcelo Da Silva Leite ◽  
Celeste Gaia

Over the past decade due the expansion of globalization there has been an increasing emphasis on internationalization among faculty, administration and accrediting agencies in the Higher Education.  Although to promote internationalization in the Higher Education, costs are a big challenge, one way to have the international actions with low cost, it is seeking for grants from different governmental agencies and foundations.The Fulbright Scholar program provides a long-standing and externally-funded means for internationalizing college and university curriculum. This article is going to share the perspective   of a Brazilian Fulbright Scholar at an American college and the institution perspective of the Fulbright scholar participation at the College.


2020 ◽  
pp. 37-43
Author(s):  
B.I. KORZHENEVSKIY ◽  
◽  
N.V. KOLOMIYTSEV ◽  
G.YU. TOLKACHEV

Putting out of using large areas of agricultural lands in the central region over the past years has led to worsening the prospects of their purposed use, although the problem of the relevance of their restoration still remains. For many years the unused land was exposed to both natural exogenous processes such as erosion, suffusion, etc. and biological and chemical changes, usually for the worse for agriculture. There are considered elements of monitoring aimed at assessing the prospects or lack of perspectives of rehabilitation of degraded lands. An energy approach to assessing the state of slopes and soils located within these slopes is presented. The main factors of natural and anthropogenic character in assessing the prospects for land restoration are their steepness, excess relative to local bases of erosion other morphological characteristics of slopes which in general is reduced to an assessment of the energy provision of slopes and soils. So the higher the energy capacity of slopes – they are less promising for development, for soils – there is a reverse picture – the higher their energy reserves, the more promising is their use. Approaches to zoning the territory for monitoring from larger taxons of natural and anthropogenic genesis to the sites of special surveillance within which the prospects for rehabilitation of the agricultural land are evaluated. The most important factor is the material expediency of such actions, i.e. before starting the restoration work it is necessary to assess the profitability or loss of the proposed event. In cases of the material expediency it is feasible as further actions to include energy assessments of slopes and soils; zoning of the object according to the steepness and oriented characteristics of soil washout; and the possibility of obtaining agronomic and meteorological data on a timely basis. The result of the work is a forecast assessment of the prospects for restoring degraded land for the intended purpose using modern databases and WEB-systems.


1973 ◽  
Vol 12 (2) ◽  
pp. 181-188
Author(s):  
Rafiq Ahmad

Like nations and civilizations, sciences also pass through period of crises when established theories are overthrown by the unpredictable behaviour of events. Economics is passing through such a crisis. The challenge thrown by the Great Depression of early 1930s took a decade before Keynes re-established the supremacy of economics. But this supremacy has again been upset by the crisis of poverty in the vast under-developed world which attained political independence after the Second World War. Poverty had always existed but never before had it been of such concern to economists as during the past twenty five years or so. Economic literature dealing with this problem has piled up but so have the agonies of poverty. No plausible and well-integrated theory of economic development or under-development has emerged so far, though brilliant advances have been made in isolated directions.


1987 ◽  
Vol 19 (5-6) ◽  
pp. 701-710 ◽  
Author(s):  
B. L. Reidy ◽  
G. W. Samson

A low-cost wastewater disposal system was commissioned in 1959 to treat domestic and industrial wastewaters generated in the Latrobe River valley in the province of Gippsland, within the State of Victoria, Australia (Figure 1). The Latrobe Valley is the centre for large-scale generation of electricity and for the production of pulp and paper. In addition other industries have utilized the brown coal resource of the region e.g. gasification process and char production. Consequently, industrial wastewaters have been dominant in the disposal system for the past twenty-five years. The mixed industrial-domestic wastewaters were to be transported some eighty kilometres to be treated and disposed of by irrigation to land. Several important lessons have been learnt during twenty-five years of operating this system. Firstly the composition of the mixed waste stream has varied significantly with the passage of time and the development of the industrial base in the Valley, so that what was appropriate treatment in 1959 is not necessarily acceptable in 1985. Secondly the magnitude of adverse environmental impacts engendered by this low-cost disposal procedure was not imagined when the proposal was implemented. As a consequence, clean-up procedures which could remedy the adverse effects of twenty-five years of impact are likely to be costly. The question then may be asked - when the total costs including rehabilitation are considered, is there really a low-cost solution for environmentally safe disposal of complex wastewater streams?


Author(s):  
Rocco J. Rotello ◽  
Timothy D. Veenstra

: In the current omics-age of research, major developments have been made in technologies that attempt to survey the entire repertoire of genes, transcripts, proteins, and metabolites present within a cell. While genomics has led to a dramatic increase in our understanding of such things as disease morphology and how organisms respond to medications, it is critical to obtain information at the proteome level since proteins carry out most of the functions within the cell. The primary tool for obtaining proteome-wide information on proteins within the cell is mass spectrometry (MS). While it has historically been associated with the protein identification, developments over the past couple of decades have made MS a robust technology for protein quantitation as well. Identifying quantitative changes in proteomes is complicated by its dynamic nature and the inability of any technique to guarantee complete coverage of every protein within a proteome sample. Fortunately, the combined development of sample preparation and MS methods have made it capable to quantitatively compare many thousands of proteins obtained from cells and organisms.


Sign in / Sign up

Export Citation Format

Share Document