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In this article the author discovers a most economic method of velocity calculation of ocean currents with the help of salinity measurements at different depths instead of density measurements‐method that has been followed by the midshipmen and marine research fellows. He also presents all possible applications of ocean currents in the development of navigation, navy, power and energy‐production, oceanography, meteorology, food and medicine‐supplies. The application of ocean current dynamics on ecological life is elaborated in the case of different kinds of fish and amphibian life. The ethico‐scientific implications of these case studies are based on the knowledge of harmonious interactions that exist between the inanimate natural world (ocean currents), the animate natural world (amphibian life) and the human world.

Whey is a by-product of paneer, cheese and casein industry and considered as a dairy waste. Worldwide, approximately 180–1,900 million tons of whey is produced annually. Whey is classified as a high pollutant due to its organic matter level. Owing to its high chemical oxygen demand and biological oxygen demand, it is a big threat to the environment. Whey contains 4.5%–5.0% lactose, 0.6%–0.7% protein, 0.4%–0.5% lipids, vitamins and minerals. Due to its high nutritional profile, it is a good substrate for the microorganisms for production of natural pigments. The purpose of this paper is to review the utilization of low cost substrate (whey) for production of various types of pigments and their applications in different sectors.

The databases for the search included: Scopus, PubMed, Science Direct, Web of Science, Research gate and Google. The main search was directed towards different types of natural pigments, stability, technologies for enhancing their production and contribution towards circular economy. Approximately 100 research papers were initially screened. A global search was conducted about natural pigments. Research articles, review papers, books, articles in press and book chapters were the type of search for writing this review paper.

Production of natural pigments using whey and their addition in food products not only improves the colour of food but also enhances the antioxidant properties of food products, helping the health benefits by chelating free radicals from the body. The sustainable use of whey for production of natural pigments can improve the bio-based economy of different industries and thereof the national economy.

Efficient utilization of whey can bring a lot more opportunities for production of natural pigments in a sustainable manner. The sustainable approach and circular economy concepts will benefit the dependent industries and health conscious consumers. The potential uses of whey for the production of natural pigments using diverse organisms are highlighted in this paper.

The purpose of this paper is to develop a new two-dimensional differential concentration corrosion mathematical model based on the knowledge that oxygen distribution on the surface of the seawater pipe is two-dimensional.

The ionic conductive layer element near the pipeline wall is regarded as the research object, and the finite element method is adopted to obtain the oxygen distribution in the layers and the natural corrosion potential and natural corrosion current of each element. Then, these element sets are regarded as a whole circuit and each element as a node on the circuit; the equation is satisfied by the corrosion potential after polarization is derived for each element according to Kirchhoff’s second law.

Matlab is used to solve the equation sets, and the overall corrosion current is calculated. The results are quite different from those considered without the differential concentration corrosion. If the differential concentration corrosion is not considered, the location with high oxygen concentration on the pipeline wall has a large corrosion potential and current. If corrosion is considered, the potential will cause polarization and the positions with original higher corrosion potential will produce anodic polarization. Meanwhile, the speed of corrosion also decreases. At the same time, the position with original lower corrosion potential will produce cathodic polarization, and the corrosion current is also increased, namely, the corrosion current and the potential will be homogenized.

A two-dimensional model for the study of concentration corrosion is proposed creatively. Based on the knowledge of electricity, a discrete equation of corrosion potential after polarization is derived. The distribution of corrosion potential and corrosion current is obtained by solving the equation, and the mechanism of concentration corrosion is analyzed. The law of concentration polarization corrosion is also obtained.

This study aims to propose a mathematical model for stacked multicell converters (SMCs), to be exploited in the analytic determination of natural voltage balancing dynamics of the flying-capacitor (FC) stacked multicell multilevel converters, i.e. investigations of the start-up behavior, dynamic response, and natural voltage balancing phenomenon.

The crux of the proposed strategy is based on the closed-form analytic solution derivation for the switching functions used in the switching of the SMCs operated under phase disposition (PD) and phase shifted carrier (PSC) pulse width modulation (PD-PSC-PWM) technique. Hence, the suggested approach develops an analytic solution for the Fourier series and associated Fourier coefficients pertinent to the switching functions of the SMCs by obtaining the switching instants of the PD-PSC-PWM modulator in terms of Kapteyn series when the frequency of the triangular carrier waveform (fc) and that of the sinusoidal reference waveform (fr) have an integer ratio, i.e. f _c  · f _r −1=k, k∈N.

This approach results into a model, first order differential equation based model, which can be readily developed for the SMCs with any number of levels expediting the investigation of their performance. Furthermore, by an experimental scrutiny conducted on a 4×2-cell-nine-level topology of an SMC, it is inferred that under PD-PSC-PWM modulation technique, FC voltages balance naturally for higher number of stacks and cells, therefore the natural balancing exist for high-level SMCs.

Despite the sophistication of the proposed methodology and mathematical model, this study presents an alternative approach with high potential of applicability for derivation of the multilevel converter mathematical model exploiting the Kapteyn (Bessel-Fourier) series.

Numeric computation results of the proposed analytic model for the SMCs and the simulation results as well as investigational measurements taken from 2×2-cell-five-level and 4×2-cell-nine-level experimental set-ups are presented in order to substantiate the suggested approach, derived model, and verification of natural balancing.

This article and its innovations are original.

The purpose of the paper is to provide to a better scientific understanding of Indonesia’s domestic gas allocation policy and its effects on the national economy and to answer the question of what best priorities can be set in allocating the natural gas for the domestic market to maximize the benefits for the national economy.

The authors apply a Computabled General Equilibrium (CGE). The Social Accounting Matrix 2008 is used to calibrate the CGE Model. There are two scenarios proposed, each is simulated with certain percentage of gas supply curtailment (50 MMSCFD, Scenario A), (100 MMSCFD, Scenario B).

It is confirmed that government’s current policy to give priority to oil production is not the optimum way to maximize added value of natural gas to Indonesian economy. While oil production generates state revenue, it is industry and petrochemical sector that induces high economic impacts because of strong backward and forward linkages.

Due to the limited data availability, it is assumed that the data on the SAM 2008 are valid for describing the structure of Indonesian economy.

The paper provides recommendation to the government to revise gas allocation policy by changing the rank of consumers’ priority.

This paper provides instruments to measure the impact of Indonesia’s domestic gas allocation policy. Finding the best hierarchy of consumer priorities is essential for maximizing added value of natural gas for the national economy.

Looks at the problem of global warming from the viewpoint of wholeness. That is, the problem of global warming will be looked at in a comprehensive study considering several aspects of the cosmos, the Earth, and the phenomenon of life. With such a broad understanding in mind, first analyzes both the disadvantageous and advantageous aspects of the current global warming. Second, compares three typical environmental conditions in which humans have lived. Third, employing the concept of global warming, looks at the myth of how ancient civilizations appeared and disappeared. Then, considering our Earth system as an open system travelling in the universe, provides an explanation for the current global warming and for global climate changes. It is expected that the explanation presented can be applied to produce long‐term predictions for climate changes.

In 1990 we compiled an annotated bibliography of official state lists of endangered, threatened, and rare species. In gathering information for that bibliography, which appeared in Reference Services Review in Spring 1991, we found numerous unofficial sources of state lists, such as those developed by universities, institutes, and Natural Heritage Programs, which also provide valuable information on statuses of endangered, threatened, and rare species. A comprehensive search for unofficial lists results in this second bibliography.

Climate change is predicted to have a significant effect on the frequency of extreme weather events and the occurrence of natural disasters. There is a need for facilities managers to mitigate against potential disruption and prepare for future events. Current practice, however, as illustrated by the literature shows that little risk assessment is currently undertaken with few organisations preparing integrated disaster management plans or business continuity plans to help them meet the challenge. This paper aims to describe the current climate change predictions and the likely consequences for building assets in the face of extreme weather events.

The paper was based on literature review of current climate change data and published research and guidance for facilities managers in preparing risk assessment and disaster plans.

The research reveals that there exists a divergence between current scientific data relating to potential effects of climate change on the built environment and the level of disaster planning and organisational resilience to extreme weather events.

The paper provides an overview of the recent changes in disaster occurrence and the potential for increasing climate‐related crisis and disasters which have potential to significantly compromise the ongoing use of an organisation's facilities. The paper concludes that facilities managers need to be proactive in their risk assessment and disaster planning.

The paper highlights the potential for increased climate change‐related natural disasters. Property assets are likely to be significantly impacted and as a consequence facilities disaster plans should address the issue of natural disaster preparedness. Current literature reveals a limited level of disaster planning is occurring.

The paper provides an important link between current climate change predictions, the increasing levels of natural disasters resulting from climate change and the potential for significant disruption to business facilities. The paper builds on earlier research highlighting the potential for climate‐related natural disaster.

The recent interconnection and trade of electricity between NSW and Victoria is likely to exacerbate any misallocation of resources due to inefficient pricing. The aim of this article is to investigate the likely divergence between electricity generation costs using current market prices of coal and natural gas, and those when coal and natural gas are priced efficiently. To do so, the paper applies the concept of full social cost pricing to five different generation technologies in the two states. It concludes that the current movement to privatisation and interconnection in the electricity sector, while it may promote pricing closer to marginal private costs, will not result in efficient outcomes in the presence of external costs and the different tax regimes which currently apply to each generation fuel and in each state.

The purpose of this paper is to present an analytical study on an unsteady magnetohydrodynamic (MHD) boundary layer flow of a rotating viscoelastic fluid over an infinite vertical porous plate embedded in a uniform porous medium with oscillating free-stream taking Hall and ion-slip currents into account. The unsteady MHD flow in the rotating fluid system is generated due to the buoyancy forces arising from temperature and concentration differences in the field of gravity and oscillatory movement of the free-stream.

The resulting partial differential equations governing the fluid motion are solved analytically using the regular perturbation method by assuming a very small viscoelastic parameter. In order to note the influences of various system parameters and to discuss the important flow features, the numerical results for fluid velocity, temperature and species concentration are computed and depicted graphically vs boundary layer parameter whereas skin friction, Nusselt number and Sherwood number at the plate are computed and presented in tabular form.

An interesting observation is recorded that there occurs a reversal flow in the secondary flow direction due to the movement of the free stream. It is also noted that a decrease in the suction parameter gives a rise in momentum, thermal and concentration boundary layer thicknesses.

Very little research work is reported in the literature on non-Newtonian fluid dynamics where unsteady flow in the system arises due to time-dependent movement of the plate. The motive of the present analytical study is to analyse the influences of Hall and ion-slip currents on unsteady MHD natural convection flow of a rotating viscoelastic fluid (non-Newtonian fluid) over an infinite vertical porous plate embedded in a uniform porous medium with oscillating free-stream.