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The assessment of the physicochemical quality of water intended for irrigation of Oued Méskiana (Oum El Bouaghi) Algeria

Abstract

The aquatic ecosystem of the Meskiana Valley (wilaya of Oum El Bouaghi) covers a large area with a permanent flow and a semi-arid climate characterized by a strong evapotranspiration. In order to determine the Physico-chemical quality, pollution and salinity of the water of the river of Meskiana and more particularly in its downstream part which is exposed to wastewater discharges, analyses were carried out at the level of three sampling points: witness, the upstream (before spill), downstream (after spill)). In order to prevent the risk of alkalization and salinization of soil, the sodium absorption rate (SAR) and the percentage of sodium were determined and represented on the Wilcox and Riverside diagram. The high concentrations of polluting chemical elements and excessive salinity obtained at the downstream site show a high risk of pollution and salinization.

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Autonomous Platform to Protect Maritime Infrastructure Facilities

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.

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Barriers and Challenges for the Implementation of the Integrated Tariff in Ukraine on the Case of Kyiv City

Summary

Subject and purpose of work: Integrated fare to date is essential for the efficient functioning of city transport services and for the involvement of citizens to shift from private to public transport. Implementation of this kind is a necessary component of the future development of the city in the direction of smart mobility.

Materials and methods: The research focuses on evaluating the barriers and challenges towards the implementation of an integrated fare in Ukraine, mainly using the city of Kyiv as a case study.

Results: The article analyzes early attempts to introduce an integrated fare, problems in the way of implementation and, basically, the experience of the EU cities, which may later be adopted. Next, it outlines some critical aspects in the relationship between government policy, city authorities, transport operators and city residents in the context of the introduction of an integrated fare.

Conclusions: The study highlights such priority challenges as legal, organizational, technical and social.

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Between retrogression and progression – a proposal for a new method to recreate the historical building layout of settlement units

Abstract

The use of cartographic sources and methods are the basic tools of historical geography. One of the main research trends in this field is the analysis of the spatial layout and number of old settlement units. The confrontation of maps with historical data allows the drawing of a town’s area at a certain time to be studied. The retrogression (R) and progression (P) methods that are currently used are imperfect and the model created (map) is usually incomplete and its reliability is limited. In the author’s opinion, the joining of retrogression and progression (a new method; combined – K)1 increases the quality of cartographic reconstruction of natural and cultural landscapes. The use of basic mathematical methods from the scope of set operations means the component reliability of the researched cartographic model can be varied because the common part of the retrogression and progression cartographic model represents mutual verification of source data. Quantitative effectiveness assessments of retrogression (R), progression (P) and the combined method (K) can be made for countable elements (e.g. buildings). As part of the conducted study, the effectiveness of separate methods was calculated: R = 76% for retrogression, P = 59% for progression and K = R ∪ P = 85% for the combined method. The mutual verification of the methods (R ∩ P) included 45% of residential buildings. The author describes the proposition of a new method and the course of verification research.

Open access
Biodiversity, Distribution and Ecology of Testate Amoebae (Arcellinida and Euglyphida) from the Bulgarian Black Sea Coast and the related brackish lakes. A Synthesis

Abstract

The studies on the marine and freshwater testate amoebae of the Bulgarian Black Sea littoral and some related coastal brackish lakes are briefly reviewed. So far, a total of 184 species and subspecies of testate amoebae from 18 families and 45 genera from orders of Arcellinida and Euglyphida were published in national and international journals. The underground waters of the Bulgarian marine sand supralittoral are better studied than the related continental lakes. A total of about 45 species of marine interstitial testate amoebae are known, so far, and a big part of them were for the first time described from the Black Sea littoral. It’s interesting to note the presence in the marine underground waters of the Black Sea littoral of many freshwater testate amoebae also, considered by us as eurybionts. That is due of the low and variable salinity of the littoral Black Sea waters during the year. The presence of some psammobiotic testate amoebae as Psammonobiotus lineare and Corythionella georgiana in some related brackish lakes is also of ecological interest. The general conclusion of the present synthesis is that the testate amoebae fauna of the Bulgarian Black Sea coast and the related with it many brackish and freshwater littoral lakes is few known yet and need more active researches.

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Blade Section Profile Array Lifting Surface Design Method for Marine Screw Propeller Blade

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.

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Breeding Biology of Booted Eagle Hieraaetus Pennatus (Gmelin, Jf, 1788): The First Study in North Africa

Abstract

Knowledge and study of breeding birds’ biology is essential to understand the dynamic, assess productivity and identify threats. The population of booted eagles (Hieraaetus pennatus) was studied during three consecutive breeding seasons (2013−2015) in the Chettabah forest. Each year, arrivals of Booted eagles are recorded during March (15 individuals in 2013, 12 in 2014 and 11 in 2015). For the three years of study, the mean breeding pair’s density was 1.23 ± 0.153/km2, incubation period ranged from 33 to 38 days, whilst the frequency distribution of clutch size was 67.6% for 2 eggs, 27% for 1 and 5.4% for 3. Amongst the 63 eggs monitored, 55 hatched. No significant variation in hatching rate was observed during the 3 years (90% in 2013, 76.19% in 2014 and 84% in 2015). The comparison of breeding parameters with those reported in Spain showed a noticeable similarity. Further investigations should be conducted to improve the provision of information to support sound management interventions of this North African population.

Open access
Building Construction Labour Productivity in Arid Climate Environment

Abstract

Productivity is a significant aspect of construction industry that plays vital role for success and failure of any construction project. This industry generates 11% to 13% of GDP all around the globe and the cost of labour in any building project is 20% to 35% of the cost of Building. On daily basis labour utilizes 30% of time on productive activities rest 70% of the time is ruined in non-productive activities, there are multi factors which are affecting the labour production in construction industry hence this study provides an overview of productivity, Total Factor productivity, method used to measure accurate productivity in construction projects. The objective of this study is find out percentage up to what extent labour production is affected due to weather conditions, however this study is carried out in arid climate region in Month of June 2018, where minimum temperature was recorded 26.0 Celsius degree at 7:30 AM and Maximum was 47.80 Celsius degree at 3:00 PM. A descriptive survey research design approach was adopted using continuous observation method of study. Project work study manual served as the research instrument to collect the data on selected building sites for 30 working days. Data collected were analyzed using descriptive statics. The results show that average monthly production of mason gang was recorded with less production of 28.759%, Carpentry gang with average monthly loss of production 16.74% & steel fixer gang had average monthly loss of production was 12.188. This concludes that prior to signing the contract for construction project. The location, environment, topography of region, capacity of construction operatives must be kept in mind to decide the proper timeline for the successful of project.

Open access
Calculation of temperature distribution and rheological properties of the lithosphere along transect IV in the Western Carpathian-Pannonian Basin region

Abstract

2D integrated modelling algorithm was used to calculate the temperature distribution in the lithosphere along the transect IV located in the Western Carpathian-Pannonian Basin area. Based on the determined temperature field and given rheological parameters of the rocks, it was possible to calculate the strength distribution for both compressional and extensional regimes, construct the strength envelopes for chosen columns of the main tectonic units of the model, and thus construct a simple rheological model of the lithosphere along transect IV. The obtained results indicate decrease of the lithospheric strength from the European platform and the Western Carpathians towards the Pannonian Basin. The largest strength (valid for all tectonic units) can be observed within the upper crust with its maxima on the boundary between upper and lower crust, decreasing towards lower crust and disappearing in the lithospheric mantle, suggesting mostly rigid deformation occurring in the upper crust. A local increase in the values of strength can be observed in the eastern segment of the Western Carpathians where crustal thickening accompanies the lithospheric thickening (formation of the lithospheric root), unlike the previous models along transects I and II, that pass through the western segment of the Western Carpathians and their lithosphere-asthenosphere boundary is almost flat and therefore no accompanying crustal thickening is observed and the decrease in strength is slow and steady.

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Carpatella rossica sp. nov., a new Late Paleocene–Eocene dinoflagellate species from European Russia and Ukraine

Abstract

Palynological study of two Paleogene core sections from the Voronezh and Rostov regions (SW Russia) and one outcrop in Ukraine revealed the presence of a new Late Paleocene–Eocene species, Carpatella rossica sp. nov. The new species is attributed to the genus Carpatella because of the presence of both apical and antapical horns. However, it is suggested that the taxon represents some features transitional between the three genera of the “Aptiana–Ventriosum complex” of Helenes (1986). Based on the observation of a thin smooth inner layer of the wall in some specimens of Carpatella rossica sp. nov., and given some morphological features of other species described after 1988, a new emendation of the genus Carpatella (Grigorovich 1969) Damassa 1988 is proposed here.

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