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Abstract

Microalgae have been mentioned as a promising feedstock for biodiesel production. In this study, microalgae Chlorella vulgaris (MCV) was cultivated in a bioreactor with wastewater. After biodiesel production from MCV oil via transesterification reaction, chemical and physical properties of MCV methyl ester were evaluated with regular diesel and ASTM standard. Besides, engine performance and exhaust emissions of CI engine fuelled with the blends of diesel-biodiesel were measured. The GC-MS analysis showed that oleic and linoleic acids were the main fatty acid compounds in the MCV methyl ester. Engine test results revealed that the use of biodiesel had led to a major decrease in CO and HC emissions and a modest reduction in CO2 emissions, whereas there was a minor increase in NOx emissions. Furthermore, there was a slight decrease in the engine power and torque while a modest increase in brake specific fuel consumption which are acceptable due to exhaust emissions reduction. The experimental results illustrate considerable capabilities of applied MVC biodiesel as an alternative fuel in diesel engines to diminish the emissions.

Abstract

Renewable producers can offer selling bids with very low marginal cost since they are not obliged to include on any cost related to the use of energy from the wind or sun. Accordingly, when the Market Operator integrates a renewable bid in the merit-order generation curve, all the generators based on conventional technologies, with higher marginal cost due to the cost of fuels, are displaced to the right. The right-shifting of the merit-order generation curve leads to a lower clearing price, a small increment of the traded energy (almost inelastic demand curve), and a reduction of the total cost of the energy traded in the wholesale market. This is the key mechanism of the well-known merit-order effect of renewables. Load-shifting (demand-side management) plans are expected to yield a reduction of the cost of the traded energy for the customers, since the cost-saving due to the energy eschewed at peak hours would be greater than the extra cost due to the increased demand at off-peak hours. This work will show that the main effects of load-shifting on the market are qualitatively similar to that of renewables, which exemplify the existence a “merit-order effect of load-shifting”. To analyse the characteristics of the merit-order effect of load-shifting, a simplified model has been developed, based on the displacement of the generation and demand curves. A set of scenarios has been generated in order to quantify the main effects on the Spanish/Iberian market for 2015.

Abstract

The objective is to carry out an analysis of remote oil spill detection using multi Remote Piloted Aircraft (RPA). A multi-RPA system provides reliable detection of an oil spill with significant advantages over other existing single RPA methods. The objective is to develop an algorithm of using multi-RPA for the monitoring of oil spills. In this paper centralized and multi-RPA algorithms for oil spill detection are analysed.

Summary

The present study is part of a survey for the identification of plant-parasitic nematodes in the rhizosphere of cultivated and wild olive trees in Crete, Greece. Sixteen species corresponding to 13 genera are added to 20 species belonging to 8 genera, previously reported in the survey. Seven nematode species, Filenchus ditissimus, Filenchus vulgaris, Ogma civellae, Pratylenchoides crenicauda, Psilenchus hilarulus, Tylenchus elegans, and Zygotylenchus guevarai, are recorded for the first time in Greece.

Abstract

The paper analyses certain aspects of organic agriculture and emphasises the need for an integrated approach in its research. The necessity of using ecologically safe agricultural production as a component of the development of modern civilized states is pointed out in the paper. The method of direct conductometry has been used to study the total mineral composition of plowed soils, which is considered as a component of “green” chemistry methods. The electrical conductivity of aqueous extracts of arable soils, in which mineral and organic fertilizers are applied, is measured. The obtained data vary between 10 and 220 μS. In the paper, for the first time, the regularities of fluctuations of the data of electrical conductivity of aqueous extracts of arable soils, in which various plant cultures had been grown, were revealed and mineral nitrogen fertilizers or organic fertilizers were introduced. Lower data of electrical conductivity are characteristic of plowed soils, in which mineral fertilizers are applied, which indirectly indicates their depletion. The advantage of using organic fertilizers as a necessary component of organic agriculture has been confirmed. It is noted that a promising area of the research is a complete use of an integrated approach to the organic agriculture being farmed in various European countries.

Summary

A prototype for pest development stages forecasting is developed in Kazakhstan exploiting data from the geoinformation technologies and using codling moth as a model pest in apples. The basic methodology involved operational thermal map retrieving based on MODIS land surface temperature products and weather stations data, their recalculation into accumulated degree days maps and then into maps of the phases of the codling moth population dynamics. The validation of the predicted dates of the development stages according to the in-situ data gathered in the apple orchards showed a good predictivity of the forecast maps. Predictivity of the prototype can be improved by using daily satellite sensor datasets and their calibration with data received from a network of weather stations installed in the orchards.

Summary

The mite fauna in foliage and litter of a sprayed alfalfa hay field with the acaricide-insecticide bifenthrin, was studied based on monthly samplings from foliage and litter in Central Greece between 2008–2009. Potential differentiations between this field and two adjacent alfalfa hay fields, which were not subjected to pesticide applications and were managed with different number of cuttings, were also evaluated in terms of population fluctuation over time, population density, species richness, diversity and spatial distribution. The sprayed field hosted 50 and 68 species and morphospecies in foliage and litter respectively, depicting high relative abundance of oribatid and prostigmatic mites. Neoseiulus aristotelisi Papadoulis, Emmanouel and Kapaxidi, was a new record for alfalfa, previously found in rice in Macedonia, Greece. The seasonal fluctuation of mites, particularly in foliage, was similar in all fields. The spatial distribution of a Zygoribatula species, which was common and dominant in all fields, was also aggregated. Finally, the sprayed field shared similar mite diversity with the two non-sprayed fields, but not similar species richness.

Abstract

The hilly regions of India have suffered many disasters, both natural and anthropogenic. In the hilly state like Uttarakhand, the hazards like flash flood, forest fires, and landslide affect the community at the large scale. These hazards cause severe physical injuries, loss of life, and at large scale property damage. To understand the impact of such natural hazards, we need to examine vulnerability of the society, so that we can define vulnerability as the status of a community to prevent, mitigate, prepare for or respond to a natural and a man-made hazard. The absence of coping strategies, which is also known as resilience, has altered the vulnerability of a community. Thus, vulnerability index of a community has to be calculated considering physical, social, economic and environmental factors associated with the community. This research paper tries to find out an integrated social vulnerability factor. The proposed integrated social vulnerability factor is determined by considering various factors, such as physical, social, economic, and environmental. All these factors increase the susceptibility of a community to the impact of hazards. Poverty, occupation, child population, literacy rate, disability, marginalization, and inequities in wealth distribution of a society or community will also change the social vulnerability. Proposed Integrated social vulnerability index for the hilly terrain of Uttarakhand incorporated local technical knowledge insight and skills, so that local people and local administration are able to identify problems and can offer a solution to resist future emergencies i.e. the proposed social vulnerability indicator will support state, local, and traditional disaster management officials to determine areas of the most sensitive populations and better mitigation operation can be performed in case of disaster.

Abstract

The importance of the honey bee lays in its huge role in pollination and, as a result, maintaining the flora of the environment and also increasing agricultural production. Temperature is the most important element of the atmosphere affecting beekeeping. Results of stationary conclusions are generalized to the area of Fars province by using geographical information system (GIS) according to direct relationship between elevation changes and temperature variations. A beekeeping capability map was then drawn for the Fars province by months of the year. The results showed that heat conditions in four months of the year, from December to March, are not suitable in most of the northern and eastern parts of the province. The southern regions with an altitude of less than 1100 meters above sea level are considered as a suitable place for deployment, wintering and beginning of bee colony activities. The most optimal months of the year for honey bee activities are May and October. For fixed beekeeping, the central strip of the province with an average height of 1500 meters above sea level is the most suitable places.

Summary

The aim of WEQUAL project (WEb service centre for QUALity multidimensional design and tele-operated monitoring of Green Infrastructures) is the development of a system that is able to support a quick environmental monitoring of riparian areas subjected to the realization of new green infrastructures (GI). The Wequal’s idea is to organize a service center able to manage both the Web Platform and the whole data collection and analysis processes. Through a personal account, the final user (designer, technician, researcher) can get access to the service and requires the evaluation of alternatives GI projects. On the Web Platform, a set of algorithms runs in order to calculate, through automatic procedures, all the ecological criteria required to evaluate a quality environmental index that describes the eco-morphological value of the monitored riparian areas. For this aim, the WEQUI index was developed, which uses 15 indicators that are easy to monitor. In this paper, the approach for environmental data collection and the procedures to perform the automatic assessment of two of the ecological criteria are described. For the computation, the implemented algorithms use data including the vegetation indexes, Digital Terrain Model (DTM), Digital Surface Model (DSM) and a 3D point cloud classification. All the raw data are collected by UAVs (Unmanned Aircraft Vehicle) equipped with a 3D Lidar, multispectral camera and RGB camera. Interpreting all the raw data collected by these sensors, using a multi-attribute approach, the WEQUI index is assessed. The computed ecological index is then used to assess the riparian environmental quality at ex-ante and ex-post river stabilization works. This index, integrated with additional not-technical or not-ecological indicators such as investment required, maintenance costs or social acceptance, can be used in multicriteria analyses in order to evaluate the intervention from a wider point of view. The platform is expected to be attractive for GI designers and policy makers by providing a shared environment, which is able to integrate the method of detection and evaluation of complex indexes and a multidimensional evaluation supported by an expert guide.