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Abstract

The argan tree is a multi-purpose tree (fruit tree, medicinal, cosmetic, and pastoral plant) found in the semi-arid and arid regions of North Africa. It is under strong human pressure such as the impact of population growth, crop expansion, overgrazing, and wood and fruit exploitation that are also the main causes of desertification in the rest of the world. Over the years, interest in this beneficial tree and demand for its products have increased: especially with the increase in the price of argan oil, which is now one of the most expensive and much in demand oils in the world. This increase has led to many socio-political, economic and cultural changes at the national, regional and local levels, especially in farming behaviour and the habits of the local population. This bibliographic research was therefore conducted in order to analyse the various changes and their consequences on the planning, conservation, and management methods implemented in the argan tree area and their effects on the habits of the local population in order to ensure the sustainability of the Argan Tree Biosphere Reserve in Morocco. Indeed, the aims of this study were, firstly, to analyse the change dynamic of argan forest area in the ABR; and secondly, to investigate the impact of various socio-political, economic and cultural changes resulting from increased prices of argan oil on planning, conservation, and management methods of argan tree ecosystem and on the habits of the local population.

Abstract

Over the years, it has been the subject of discussions whether efficiency-oriented interventions contribute to an equity distribution of wealth across regions and whether equity orientation is a source of inefficiency. While efficiency refers to the maximization of growth in the national economy, convergence-oriented policy is focused on equalizing the level of development at interregional level. The case of Georgia was studied as a developing country facing various challenges in terms of economic growth and regional divergence. This article provides an overview of the economic development trends taking place in the regions of Georgia and reveals the high level of divergence within the country. A logarithmic model was created and used to run simulations to predict the possible results of convergence-oriented policy in Georgia. In order to make the forecast we estimated GDP per capita and average growth rates in all the Georgian regions. Use of the model allowed us to answer two main questions: (1) If the last 5 and 10 year average growth rates are maintained, how long will it take for the poorest region to converge to the wealthiest one? (2) What should be the minimum growth rate in the poorest region for the upcoming 5, 10 and 20 years in order to converge to the wealthiest capital? Results of the calculations showed that convergence between regions can only be achieved by slowing down economic growth in relatively wealthier regions and by focusing on the development of the poorest ones. The results of the study revealed that the convergence process will be faster for the regions with medium or big cities and growth centres. Therefore, creating competitive growth centres would be a reasonable regional policy objective to promote fast economic growth and future convergence without redirecting the growth process from more developed areas to lagging ones.

Abstract

Climate change is a major global issue, which is becoming increasingly important on the international scene. As it has a direct impact on ecosystems and societies. Water is at the heart of these changes. The aim of this article was to capture all the microeconomic and macroeconomic effects of resource availability, and to propose a sequential dynamic computable general equilibrium (CGE) model that takes into account long-term changes in the availability of the primary resource (water supply) with regard to population growth (demand). The results show that the very negative effects on the economy of water shortages could be counteracted by the introduction of a marginal cost demand management policy. This makes it possible to better manage the scarcity of this resource. In fact, the model shows that when Algeria is facing water deficits, the marginal cost tariff policy reverses the trends of an economy that would maintain a tariff policy at average cost. Total investment increases, and total welfare deteriorates less. The drop in the price of water (input and final good), generated by the transition from an average cost pricing to a marginal cost pricing, generates an expansion of many sectors, and stimulates economic activity which reduces the rate of unemployment.

Abstract

An Environmental Risk Assessment is an efficient technical and analytical method for analyzing environmental impacts and it supports the decision-making process connected with projects variants by using historical data collection, identification of regional risk sources, probability and impact estimation of signal risk type. In this article, an Environmental Risk Assessment was performed for groundwater quality in the region of municipal landfills in Tychy-Urbanowice (Southern Poland) to assess the impact of various factors on the quality of groundwater in the region. The assessment used qualitative and quantitative risk analysis methods, including cause and consequence analysis, completion of an effect/probability matrix and utilization of the SWOT analysis method. The results of the assessment indicate that use of the SWOT analysis was the best method for groundwater risk assessment in the examined area. The analysis included an assessment of the spatial and temporal variability of leachate and groundwater quality (using data from a groundwater monitoring system), simulation of the longevity of both the top and bottom security system, spatial planning and an assessment of the impact of other parameters on groundwater, terrain and climatic conditions. The overall result for this analysis for the likely potential groundwater hazard was a score of -4. For the purposes of further risk analyses, it is possible to consider additional factors that are likely to affect the water quality of the area under investigation or to use other methods that will be based on a time series analysis.

Abstract

Energy needs are determined by three main factors: population growth, the economic development of society, and the scientific and technical level of production processes. These needs are increasing year by year in the world and in 2018 they exceeded 13.5 billion tons of oil equivalent. More and more countries are developing and implementing plans and strategies for significant coverage, within 50-100%, of their energy needs through renewable energy sources. The findings of this study revealed that Ukraine’s energy demand per year is 200 million tons of oil equivalent of energy resources. Currently, the share of renewable energy in the structure of energy consumption in Ukraine is 4.4%. The authors also acknowledged that at the same time, 115 million tons of agricultural plant waste and about 97 million tons of animal waste are generated annually in Ukraine, which makes it possible to produce 7.21 million tons of oil equivalent and 2.2 million tons of oil equivalent, respectively from these. The study found that the production of biofuels from agricultural waste will have social, economic and environmental effects. An efficiency matrix was constructed by the authors to determine these effects. Using the SWOT method of analysis, factors that will affect the development of biofuel production from agricultural waste were determined.

Abstract

Mining is essentially an important income generating activity in the developing countries of the world. This is beneficial for their social and economic development and thus developing countries place a great dependence on their exploitation of mineral resources. The focal points for discussion in this article are the process of limestone mining, growth trends in limestone production, allocation of royalties, benefit sharing between limestone miners and local communities. The article undertakes an income-expenditure analysis of limestone contractors and transporters and considers local environmental issues including land degradation, rehabilitation, and compensation problems connected with the mining process. This study has been carried out in the Banor-Shiva limestone mining region which is located in the Sirmaur District of Himachal Pradesh State in India. The study calculated compound annual growth rates and benefit sharing between the miners and local people, and made a calculation of transport costs based on the mining rules in force and the actual practice prevailing in the region. The overall compound annual growth rates for limestone production are 16.2%, 1.6 % and 3.9% and for royalties are 14.1%, 8.5%, and 7.8 5 respectively for the State, District, and Banor-Shiva mining region over the study period. However, these growth rates have continuously decelerated and even found to be negative between the periods following the National Mineral Policies Act of 1993 and 2008. There is a sizeable divergence between the benefits from limestone mining shared between the indigenous communities and limestone miners highlighting the poor land acquisition practices in the study area. The financial benefits awarded by the miners in 2016-17 to the local communities are 1.22% whereas miners have appropriated the lion’s share with 81.37% of total limestone value. The revenue to the Government is 4.30% of market value of limestone. The transportation of limestone from quarry sites to the point of final sale is the largest cost factor in limestone miners’ expenditure which is 10% of the total market value of limestone. Adverse impacts of limestone mining operations in the vicinity such as public health problems, change in land use and cropping patterns, water pollution, lack of rehabilitation of the abandoned mines and unjust division of limestone receipts are the main contentious issues in the study area which are affecting the production and process of limestone mining. These have been reflected in the declining growth rates in production and royalties accrued from limestone produce.

Abstract

As a type of natural energy resource, wind power is used in the modern implementation of wind-assisted technologies as a method for reducing the fuel consumption and environmental pollution of ocean-going ships. In order to promote the full usage of ocean wind energy for cargo ships, an innovative type of ship propulsion-assisted wing sail is proposed in this paper. The propulsion efficiency of this new wing sail can be increased by enlarging its area in both the transverse and vertical directions in good weather conditions, and it can be folded up automatically in poor weather conditions, improving the sailing safety of the ship. The sail parameters relating to the gaps and rotation angles between different parts of the wing sail are compared, and the values giving the best aerodynamic performance are identified using CFD simulation technology. The results for the lift and drag coefficients for the new wing sail at different attack angles are also compared with those of traditional aerofoil sails, including an arc-shaped rigid sail and a variable-camber sail proposed in 2015. From the viewpoint of the sailing performance of the vessel, our results demonstrate that this new type of wing sail has good aerodynamic performance and can reduce fuel costs for commercial vessels.

Abstract

The design of a floating, innovative device for river water aeration and conversion of mechanical energy to electrical energy required the analysis of a number of geometrical and dynamic features. Such an analysis may be carried out on the basis of existing methods of numerical fluid mechanics. Models of pressures, forces and torques characteristic for the conversion of watercourse energy were developed for two basic concepts of innovation. These pressures, forces and torques were calculated, designed, and experimentally determined for the variable geometric form and dimensions of the designed working elements of the innovative roller-blade turbine rotor.

Abstract

Problems regarding the security of maritime infrastructure, especially harbours and offshore infrastructure, are currently a very hot topic. Due to these problems, there are some research projects in which the main goal is to decrease the gap and improve the methods of observation in the chosen area, for both in-air and underwater areas. The main goal of the paper is to show a new complex system for improving the security of the maritime infrastructure by means of many methods of observation – such as thermovision, optical devices, and radar systems – generally by means of an electromagnetic wave as a carrier of information in the air and acoustical methods in water. The system can be applied to the protection of maritime infrastructure as well as the coastal zone.

Abstract

The lifting surface model is widely used in screw propeller design and analysis applications. It serves as a reliable tool for determination of the propeller blade mean line and pitch distribution. The main idea of this application was to determine the blade shape that would satisfy the kinematic boundary condition on its surface with the prescribed bound circulation distribution over it. In this paper a simplified lifting surface method is presented – in which the 3D task for the entire blade is replaced by a set of 2D tasks for subsequent blade section profiles.