Abstract: This paper presents the optimal design and simulation of a grid-connected Photovoltaic (PV) system to supply electric power to meet the energy demand by Electrical Department in University of Tripoli Libya. Solar radiation is the key factor determining electricity produced by photovoltaic (PV) systems. This paper is designed to develop a novel method to calculate the solar photovoltaic generation capacity on the basis of Mean Global Solar Radiation data available for Tripoli Libya and finally develop a system design of possible plant capacity for the available roof area. MatLab/Simulink Programming tools and monthly average solar radiation data are used for this design and simulation. The specifications of equipments are provided based on the availability of the components in the market. Simulation results and analyses are presented to validate the proposed system configuration.
Abstract: The present study consisted of an applied test in meat
system to assess the effectiveness of three bio agents bacteriocinproducing
strains: Lm24: Lactobacillus sakei, Lm14and Lm25:
Pediococcus spp. Two tests were carried out: The ex situ test was
intended for three batches added with crude bacteriocin solutions at
12.48 AU/ml for Lm25 and 8.4 AU/ml for Lm14 and Lm24. However, the
in situ one consisted of four batches; three of them inoculated with
one bacteriocinogenic Lm25, Lm14, Lm24, respectively. The fourth one
was used in mixture: Lm14+m24 at approximately of 107 CFU/ml. The
two used tests were done in the presence of the pathogen
St. aureus ATCC 6538, as a test strain at 103 CFU/ml. Another batch
served as a positive or a negative control was used too. The
incubation was performed at 7°C. Total viable counts, staphylococci
and lactic acid bacteria, at the beginning and at selected times with
interval of three days were enumerated. Physico-chemical
determinations (except for in situ test): pH, dry mater, sugars, fat and
total protein, at the beginning and at end of the experiment, were
done, according to the international norms. Our results confirmed the
ex situ effectiveness. Furthermore, the batches affected negatively the
total microbial load over the incubation days, and showed a
significant regression in staphylococcal load at day seven, for Lm14,
Lm24, and Lm25 of 0.73, 2.11, and 2.4 log units. It should be noticed
that, at the last day of culture, staphylococcal load was nil for the
three batches. In the in situ test, the cultures displayed less inhibitory
attitude and recorded a decrease in staphylococcal load, for Lm14,
Lm24, Lm25, Lm14+m24 of 0.73, 0.20, 0.86, 0.032 log units. Therefore,
physicochemical analysis for Lm14, Lm24, Lm25, Lm14+m24 showed an
increase in pH from 5.50 to 5.77, 6.18, 5.96, 7.22, a decrease in dry
mater from 7.30% to 7.05%, 6.87%, 6.32%, 6.00%.This result
reflects the decrease in fat ranging from 1.53% to 1.49%, 1.07%,
0.99%, 0.87%; and total protein from 6.18% to 5.25%, 5.56%,
5.37%, 5.5%. This study suggests that the use of selected strains as
Lm25 could lead to the best results and would help in preserving and
extending the shelf life of lamb meat.
Abstract: Soil is a complex physical and biological system that provides support, water, nutrients and oxygen to the plants. Apart from these, it acts as a connecting link between inorganic, organic and living components of the ecosystem. In recent years, presence of xenobiotics, alterations in the natural soil environment, application of pesticides/inorganic fertilizers, percolation of contaminated surface water as well as leachates from landfills to subsurface strata and direct discharge of industrial wastes to the land have resulted in soil pollution which in turn has posed severe threats to human health especially in terms of causing carcinogenicity by direct DNA damage. The present review is an attempt to summarize literature on sources of soil pollution, characterization of pollutants and their consequences in different living systems.
Abstract: The objectives of this study (baseline study, n = 20) were to implement Matlab procedures for quantifying selected static balance variables, establish baseline data of selected variables which characterize static balance activities in a population of healthy young adult males, and to examine any trial effects on these variables. The results indicated that the implementation of Matlab procedures for quantifying selected static balance variables was practical and enabled baseline data to be established for selected variables. There was no significant trial effect. Recommendations were made for suitable tests to be used in later studies. Specifically it was found that one foot-tiptoes tests either in static balance is too challenging for most participants in normal circumstances. A one foot-flat eyes open test was considered to be representative and challenging for static balance.
Abstract: The objectives of this study are to increase tourism products and to develop family agro-tourism. The research methodology was to analyze internal and external situations according to MP-MF and the MC-STEPS principles.
The results of this study highlight following necessary improvements; extend the cycling routes, increase the number of bicycle rental shops, offer a recreation place for the elders, organize a space for the floating market products and increase tourism activities throughout the year. In ‘places or distribution channel’ we discuss the improvement of facilities, specifically the routes to facilitate elder visitors and visitors on wheelchairs and furthermore the arrangement of educational trips to relevant centers in the community. In ‘promotions’, we discuss the implementation of an “all inclusive package” were the agro-tourism program, health-conscious program and the elderly fun program converge.
Abstract: Removal of various toxic species from aqueous streams is of great importance. Sorption is one of the important remediation procedures as it involves the use of cheap and easily available materials. Also the advantage of regeneration of the sorbent involves the possibility of using novel sorbents. Nanosorbents are very important as the removal is based on the surface phenomena and this is greatly affected by surface charge and area. Functionalization has been very important to bring about the removal of metal ions with greater selectivity.
Abstract: Chromium bearing Austempered Ductile Iron (ADI) has been recently in the news for its improved wear performance over the ADI. The work presented below was taken up to study the effect of different austenitisation temperatures on the microstructure and wear performance of the Carbidic Austempered Ductile Iron (CADI). In this investigation Cr bearing ductile iron was subjected to austempering treatment to obtain an ausferritic microstructure. Two different austenitisation temperatures were selected whereas, the austempering temperature and time was kept unchanged. Microstructure and wear performance of this alloy, austenitized at two different temperatures was studied.
Abstract: Immobilization of lipase enzyme produced from palm oil mill effluent (POME) by the activated carbon (AC) among the low cost support materials was optimized. The results indicated that immobilization of 94% was achieved by AC as the most suitable support material. A sequential optimization strategy based on a statistical experimental design, including one-factor-at-a-time (OFAT) method was used to determine the equilibrium time. Three components influencing lipase immobilization were optimized by the response surface methodology (RSM) based on the face-centered central composite design (FCCCD). On the statistical analysis of the results, the optimum enzyme concentration loading, agitation rate and carbon active dosage were found to be 30 U/ml, 300 rpm and 8 g/L respectively, with a maximum immobilization activity of 3732.9 U/g-AC after 2 hrs of immobilization. Analysis of variance (ANOVA) showed a high regression coefficient (R2) of 0.999, which indicated a satisfactory fit of the model with the experimental data. The parameters were statistically significant at p
Abstract: In the article are considered the problems arising at increasing of transferring from rolling stock axles on rail loading from 210 KN up to 270 KN and is offered for rail strength analysis definition of rail force loading complex integral characteristic with taking into account all affecting force factors that is characterizing specific operation condition of rail structure and defines the working capability of structure.
As result of analysis due mentioned method is obtained that in the conditions of 270 KN loading the rail meets the working assessment criteria of rail and rail structures: Strength, rail track stability, rail links stability and its transverse stability, traffic safety condition that is rather important for post-Soviet countries railways.
Abstract: HF Communication system is one of the attractive fields among many researchers since it can be reached long-distance areas with low-cost. This long-distance communication can be achieved by exploiting the ionosphere as a transmission medium for the HF radio wave. However, due to the dynamic nature of ionosphere, the channel characteristic of HF communication has to be investigated in order to gives better performances. Many techniques to characterize HF channel are available in the literature. However, none of those techniques describe the HF channel characteristic in low-latitude regions, especially equatorial areas. Since the ionosphere around equatorial region has an ESF phenomenon, it becomes an important investigation to characterize the wideband HF Channel in low-latitude region. On the other sides, the appearance of software-defined radio attracts the interest of many researchers. Accordingly, in this paper a SDR-based channel measurement system is proposed to be used for characterizing the HF channel in low-latitude region.
Abstract: This article analyzes the applicability of known renewable energy technical means as mobile power sources under the field and extreme conditions. The requirements are determined for the parameters of mobile micro HPP. The application prospectively of the mobile micro HPP with intelligent control systems is proved for this purpose. Variants of low-speed electric generators for micro HPP are given. Variants of designs for mobile micro HPP are presented with direct (gearless) transfer of torque from the hydraulic drive to the rotor of the electric generator. Variant of the hydraulic drive for micro HPP is described workable at low water flows. A general structure of the micro HPP intelligent system control is offered that implements the principle of maximum energy efficiency. The legitimacy of construction and application of mobile micro HPP is proved as electrical power sources for life safety of people under the field and extreme conditions.
Abstract: The surface properties of many materials can be readily and predictably modified by the controlled deposition of thin layers containing appropriate functional groups and this research area is now a subject of widespread interest. The layer-by-layer (lbl) method involves depositing oppositely charged layers of polyelectrolytes onto the substrate material which are stabilized due to strong electrostatic forces between adjacent layers. This type of modification affords products that combine the properties of the original material with the superficial parameters of the new external layers. Through an appropriate selection of the deposited layers, the surface properties can be precisely controlled and readily adjusted in order to meet the requirements of the intended application. In the presented paper a variety of anionic (poly(acrylic acid)) and cationic (linear poly(ethylene imine), polymers were successfully deposited onto the polypropylene nonwoven using the lbl technique. The chemical structure of the surface before and after modification was confirmed by reflectance FTIR spectroscopy, volumetric analysis and selective dyeing tests. As a direct result of this work, new materials with greatly improved properties have been produced. For example, following a modification process significant changes in the electrostatic activity of a range of novel nanocomposite materials were observed. The deposition of polyelectrolyte nanolayers was found to strongly accelerate the loss of electrostatically generated charges and to increase considerably the thermal resistance properties of the modified fabric (the difference in T50% is over 20oC). From our results, a clear relationship between the type of polyelectrolyte layer deposited onto the flat fabric surface and the properties of the modified fabric was identified.
Abstract: The wireless communication is one of the widely used methods of data transfer at the present days. The benefit of this communication method is the partial independence of the infrastructure and the possibility of mobility. In some special applications it is the only way how to connect. This paper presents some problems in the implementation of a sensor network connection for measuring environmental parameters in the area of manufacturing plants.
Abstract: This article deals with the possibility of increasing efficiency, reliability and safety of the system for teledosimetric data collection management and their evaluation as a part of complex study for activity “Research of data collection, their measurement and evaluation with mobile and autonomous units” within project “Research of monitoring and evaluation of non-standard conditions in the area of nuclear power plants”. Possible weaknesses in existing system are identified. A study of available cluster solutions with possibility of their deploying to analysed system is presented
Abstract: The objective is to identify the contributions from the introduction of the computerized system deal within the Accounting Department of Brazilian Navy Financial Directorship and its possible effects on the budgetary and financial harvest of Brazilian Navy. The relevance lies in the fact that the management process is responsible for the continuous improvement of organizational performance through higher levels of quality in their activities. Improvements in organizational processes have direct effects on crops cost, quality, reliability, flexibility and speed. The method of study of this research is the case study. The choice of case study attended, among other demands, a need for greater flexibility to study processes related to a computerized system. The sources of evidence were used literature, documentary and direct observation. Direct observation was made by monitoring the implementation of the computerized system in the Division of Management Analysis. The main findings of the study point to the fact that the computerized system may contribute significantly to the standardization of information. There was improvement of internal processes in the division of management analysis, made possible the consolidation of a standard management and performance analysis that contribute to global homogeneity in the treatment of information essential to the process of decision making. This study has limitations related to the fact the search result be subject exclusively to the case studied, and it is impossible to generalize to other organs of government.
Abstract: The influence of transverse surface roughness on EHL characteristics has been investigated numerically using an extensive set of full EHL line contact simulations for shear-thinning lubricants under pure sliding condition. The shear-thinning behavior of lubricant is modeled using Carreau viscosity equation along with Doolittle-Tait equation for lubricant compressibility. The surface roughness is assumed to be sinusoidal and it is present on the stationary surface. It is found that surface roughness causes sharp pressure peaks along with reduction in central and minimum film thickness. With increasing amplitude of surface roughness, the minimum film thickness decreases much more rapidly as compared to the central film thickness.
Abstract: Plant preparations from thyme and garlic have been shown to be effective acaricides against the poultry red mite, Dermanyssus gallinae. In a layer house with a history of D. gallinae problem, mites were detected in the monitoring traps for the first time and number of them was counted. Then, some rows of layer house was sprayed twice using a concentration of 0.21 mg/cm2 thyme essential oil and 0.07 mg/cm2 garlic juice and a similar row was used as an untreated control group. Red mite traps made of cardboard were used to assess the mite density during days 1 and 7 after treatment and always removed after 24 h. the collected mites were counted and the efficacy against all mite stages (larvae, nymphs and adults) was calculated. Results showed that on day 1 and 7 after the administration of garlic extract efficacy rate was 92.05% and 74.62%, respectively. Moreover, efficacy rate on day 1 and 7 was 89.4% and 95.37% when treatment was done with thyme essential oil. It is concluded that using garlic juice to control of D. gallinae is more effective on short time. But thyme essential oil has a long time effect in compare to garlic preparation.
Abstract: When a building is located in an urban area, it is
exposed to a wind of different characteristics then wind over an open
terrain. This is development of turbulent wake region behind an
upstream building. The interaction with upstream building can
produce significant changes in the response of the tall building. Here,
in this paper, an attempt has been made to study wind induced
interference effects on tall building. In order to study wind induced
interference effect (IF) on Tall Building, initially a tall building
(which is termed as Principal Building now on wards) with square
plan shape has been considered with different Height to Width Ratio
and total drag force is obtained considering different terrain
conditions as well as different incident wind direction. Then total
drag force on Principal Building is obtained by considering adjacent
building which is termed as Interfering Building now on wards with
different terrain conditions and incident wind angle. To execute
study, Computational Fluid Dynamics (CFD) Code namely Fluent
and Gambit have been used.
Abstract: Qatar’s primary source of fresh water is through
seawater desalination. Amongst the major processes that are
commercially available on the market, the most common large scale
techniques are Multi-Stage Flash distillation (MSF), Multi Effect
distillation (MED), and Reverse Osmosis (RO). Although commonly
used, these three processes are highly expensive down to high energy
input requirements and high operating costs allied with maintenance
and stress induced on the systems in harsh alkaline media. Beside that
cost, environmental footprint of these desalination techniques are
significant; from damaging marine eco-system, to huge land use, to
discharge of tons of GHG and huge carbon footprint.
Other less energy consuming techniques based on membrane
separation are being sought to reduce both the carbon footprint and
operating costs is membrane distillation (MD).
Emerged in 1960s, MD is an alternative technology for water
desalination attracting more attention since 1980s. MD process
involves the evaporation of a hot feed, typically below boiling point
of brine at standard conditions, by creating a water vapor pressure
difference across the porous, hydrophobic membrane. Main
advantages of MD compared to other commercially available
technologies (MSF and MED) and specially RO are reduction of
membrane and module stress due to absence of trans-membrane
pressure, less impact of contaminant fouling on distillate due to
transfer of only water vapor, utilization of low grade or waste heat
from oil and gas industries to heat up the feed up to required
temperature difference across the membrane, superior water quality,
and relatively lower capital and operating cost.
To achieve the objective of this study, state of the art flat-sheet
cross-flow DCMD bench scale unit was designed, commissioned, and
tested. The objective of this study is to analyze the characteristics and
morphology of the membrane suitable for DCMD through SEM
imaging and contact angle measurement and to study the water
quality of distillate produced by DCMD bench scale unit.
Comparison with available literature data is undertaken where
appropriate and laboratory data is used to compare a DCMD distillate
quality with that of other desalination techniques and standards.
Membrane SEM analysis showed that the PTFE membrane used
for the study has contact angle of 127º with highly porous surface
supported with less porous and bigger pore size PP membrane. Study
on the effect of feed solution (salinity) and temperature on water
quality of distillate produced from ICP and IC analysis showed that
with any salinity and different feed temperature (up to 70ºC) the
electric conductivity of distillate is less than 5 μS/cm with 99.99%
salt rejection and proved to be feasible and effective process capable
of consistently producing high quality distillate from very high feed
salinity solution (i.e. 100000 mg/L TDS) even with substantial
quality difference compared to other desalination methods such as
RO and MSF.
Abstract: Concentric bracing systems have been in practice for many years because of their effectiveness in reducing seismic response. Depending on concept, seismic design codes provide various response modification factors (R), which itself consists of different terms, for different types of lateral load bearing systems but configuration of these systems are often ignored in the proposed values. This study aims at considering the effect of different x-bracing diagonal configuration on values of ductility dependent term in R computation. 51 models were created and nonlinear push over analysis has been performed. The main variables of this study were the suitable location of X–bracing diagonal configurations, which establishes better nonlinear behavior in concentric braced steel frames. Results show that some x-bracing diagonal configurations improve the seismic performance of CBF significantly and explicit consideration of lateral load bearing systems seems necessary.