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This study aimed to determine whether autochthonous high-intensity D. repens microfilaremia leads to haematological changes in companion dogs. Dogs with hypermicrofilaremia presented to the District Veterinary Centre, Kannur were selected for the study. A total of one hundred animals were positive for hypermicrofilariaemia with D. repens based on peripheral blood smear examination and Knott’s test. Of these, three dogs were concurrently positive for sheathed microfilaria (MF) of Brugia spp. Interestingly, an adult live worm of D. repens approximately eight cm in length was detected on a subcutaneous mass on the hind limb of a hypermicrofilaremic animal in the study. We compared the hematological parameters of 100 autochthonous hypermicrofilaremic dogs and 15 uninfected dogs. The hematological findings in the study are nonregenerative mild to moderate anemia, moderate to severe thrombocytopenia, leucocytosis with granulocytosis, lymphocytosis and monocytosis in comparison to the uninfected group of dogs. The pathogenicity of naturally occurring hypermicrofilaremia is poorly studied, and knowledge of its epidemiology, host-parasite relationship and impact on various organs is warranted for better prevention and control, especially in hot-spot areas.

Seizure is the most common neurological presentation in dogs. Epilepsy is defined as a disease of the brain characterised by enduring predisposition to generate epileptic seizures. The dogs less than 6 months and more than 6 years are diagnosed with structural epilepsy and between 6 months and 6 years are diagnosed with idiopathic epilepsy commonly with certain exceptions in co – morbid conditions. So, the prevalence of epilepsy in relation to age, breed and sex was carried out. Among the breeds the pure breeds were grouped together which was higher in percentage and compared with non – descript native breeds and in each breed and age group males dominated females and number of dogs in age group of 6 months to 6 years was higher. Chi – square analysis was done to find out significant association between Age and breed, breed and sex, age and sex. There was significant association between breed and sex which needs further detailed analysis. This may be of interest in future epilepsy research in dogs.

Cattle and buffalo are known to be the symbol of wealth in rural India from time immemorial. To ensure the attainable socio-economic benefits from cattle and buffalo reaching the rural poor through effective strategies, a more complete extrapolation of cattle and buffalo population in the country for the future using forecasting tools was attempted in this study. Data on cattle and buffalo population from 1950-51 to 2016-17 were collected from various reports of BAHS and FAO. Various time series forecasting models were employed to identify the growth patterns and to predict the future trends in bovine population. The forecasting models used were compared to identify the best fit model. From the results of the study, it could be discerned that the Damped Trend Exponential Smoothing was found to be the best fit model for cattle population and forecasted value indicated that the cattle population in the country would be almost stagnant in the next three decades. The cattle population forecast showed a slightly decreasing trend from 2010-11 with 194.184 million to 187.661, 188.177, 188.191, and 188.192 millions in 2020-21, 2030-31, 2040-41 and 2050-51, respectively. However, in case of buffaloes, the Brown Exponential Smoothing model was found to be the best fit model and the buffalo population was predicted to increase from 2000-01 and the predicted populations were 116.663, 127.787, 138.910 and 148.921 million in 2020-21, 2030-31, 2040-41 and 2050-51 respectively.

The study proposes a method for preliminary and estimative sizing of the main components of solar district heating systems, with seasonal thermal storage. The main parameters determined by this method, are the aperture area of the solar thermal collectors and the volume of the seasonal thermal storage. The proposed method is only estimative, but it provides the necessary input data for the investigation of the dynamic thermal behavior of such systems. The main advantage of the method is that it requires only very few and accessible input data. Two situations are considered: the first in which available climatic data such as annual global solar radiation on horizontal plane and annual average temperature can be used in calculations, and the second in which such data is not available and should be determined through interpolation. With the proposed interpolation functions the annual global solar radiation on horizontal plane, the annual average temperature and the annual global efficiency of the solar thermal collectors were determined. The errors of the estimations are ranging within the intervals of (-15.6 … +25.8) % for annual global solar radiation on horizontal plane and (-10.8 … 19.1) % for annual global efficiency of the solar thermal collectors. The maximum deviations for the annual average temperature estimations were (-4.23 … +5.37) °C. With this limited accuracy, the proposed interpolation functions can be used for latitudes between (0 - 70) °, annual global solar radiation on horizontal plane between (704 - 2337) kWh/m2/year and annual average temperatures ranging within the interval of (2 - 30) °C.

Magneto-ionics, by which the magnetic properties of a thin layer can be modified through the migration of ions within a liquid or solid electrolyte, is a fast developing research field. This is mainly due to the perspective of energy efficient magnetic devices, in which the magnetization direction is controlled not by a magnetic field or an electrical current, as done in traditional devices, but by an electric field, leading to a considerable reduction of energy consumption. In this work, the interfacial perpendicular magnetic anisotropy (PMA) of a series of Pt/Co/oxide trilayers covered by a ZrO$_2$ layer, acting as a ionic conductor, was finely tuned by a gate voltage at room temperature. The non-volatility and the time evolution of the effect point at oxygen ion migration across the ZrO$_2$ layer as the driving mechanism. A large variation of the PMA is obtained by modifying the degree of oxidation of the cobalt layer with the flux of oxygen ions: the easy magnetization axis can be switched reversibly from in-plane, with an under-oxidized Co, to in-plane, with an over-oxidized Co, passing through an out-of-plane magnetization with maximum PMA. The switching time between the different magnetic states is limited by the oxygen ion drift velocity through the multilayer structure. This was shown to depend exponentially on the applied bias voltage, and could be varied by over 5 orders of magnitude, from several minutes to a few ms. On the other hand, for a fixed gate-voltage, the oxidation of the cobalt layer decreases exponentially as a function of time. This behavior is in agreement with the theoretical model developed by Cabrera and Mott (1949) to explain the growth of very thin oxides at low temperatures. The possibility to explain the observed effect with a relatively simple theoretical model opens the possibility to engineers materials with optimized properties., 8 pages, 6 figures

Background: Various mathematical models have been tried by different researchers to fit the lactation curves in indigenous, exotic and crossbred cows maintained in organised farms only. Hence, this study was aimed to fit various lactation models and to identify the best fit model (s) for prediction of milk production in crossbred dairy cows in field conditions.Methods: Multistage random sampling procedure was used for selection of 100 dairy cows for the purpose of data collection. The monthly milk yield data (up to 10 months of lactation) of the selected crossbred cows reared in field conditions of Tamil Nadu State, relating to the period from 2017-20, were collected for lactation curve modelling. The milk data so collected were used to fit 14 lactation curve models in the study. The highest Coefficient of Determination (R²) value and the least Root Mean Square Error (RMSE) value were used as the criteria to select the best fit model(s).Result: The overall average total milk production was estimated to be 2223.19 kg per lactation in 10 months of lactation in the selected crossbred cows. Average daily milk yield at the first month of lactation was 9.16 kg and the highest daily milk yield of 9.56 kg was observed at the second month of lactation. At the end of the lactation, the lowest yield was 5.01 kg per day and hence the overall average daily milk yield was found to be 7.41 kg. Based on the selection criteria, the Mitscherlich X Exponential model was identified as the best fit model, followed by Ali and Schaeffer and Morant and Gnanasakthy model for prediction of milk production in crossbred dairy cows reared in field conditions and the estimated lactation curve model parameters a, b, c and d values for the best fit model were 331.71, 1519.82, 9.56 and 0.07 kg, respectively.

International audience; The accurate estimation of a concentrated solar power plant production is an important issue because of the fluctuations in meteorological parameters like solar radiation, ambient temperature, wind speed, and humidity. In this work, three models were conducted in order to estimate the hourly electric production of a parabolic trough solar thermal power plant (PTSTPP) located at Ain Beni-Mathar in Eastern Morocco. First, two analytical models are considered. The first analytical model (AM I) is based on calculating the heat losses of parabolic trough collectors (PTCs), while the second analytical model (AM II) is based on the thermal efficiency of PTCs. The third model is an artificial neural networks (ANN) model derived from artificial intelligence techniques. All models are validated using one year of real operating data. The simulation results indicate that the ANN model performs much better than the analytical models. Accordingly, the ANN model results show that the estimated annual electrical energy is about 42.6 GW h/year, while the operating energy is approximately 44.7 GWh/year. The frequency of occurrence shows that 86.77% of hourly values were estimated with a deviation of less than 3 MW h. The developed ANN model is readily useable to estimate energy production for PTSTPP.

The chapter presents the fundamentals for performance evaluation of different types of solar thermal collectors (STC): flat thermal collectors (FTC), evacuated thermal collectors (ETC) and concentrated thermal collectors (CTC). All the STC can be integrated in the built environment. The chapter presents the mathematical modelling of the solar geometry and of the thermal efficiency of STC. The mathematical model was implemented in Excel and proved its capability to provide accurate results. The performance parameters of the collectors that were evaluated are the thermal efficiency and the specific thermal energy production (W/m2). The mentioned parameters of performance were evaluated in the different climatic conditions specific to multiple locations worldwide (Europe, USA and Africa), available from the data provided by the typical meteorological year (TMY). The input data of solar radiation and of ambient temperature were considered based on hourly variation. Real technical data and characteristics of each solar collector were made available by independent testing laboratories and by technical leaflets were considered in the investigation.

Starting from the equation of Einstein (E = m·c2), the chapter proposes a simple and fundamental presentation of the fission and fusion principles, together with some of their applications: nuclear reactors and nuclear propulsion vessels and submarines. Fission and fusion are chosen between the multiple forms of energy, as being the most important forms of nuclear energy, directly related with the equation of Einstein. Some characteristics of solar energy, produced from the fusion process inside the Sun, are deducted from the same equation of Einstein: thermal power of solar radiation; specific power of solar radiation; surface temperature of the Sun; solar constant on different planets, etc. The yearly variation of the solar radiation on each planet of the solar system is also presented.

A key component of the concept of Smart City is the use of energy efficient technology for household and nonresidential building applications. In this context, the study presents an experimental setup with phase change material (PCM) encapsulated in spherical shells and an analysis of phase change materials for energy efficient cold storage applications using air as heat transfer fluid. The solidification and melting processes are investigated and compared with the thermal behavior indicated by the differential scanning calorimetry (DSC) signals generated at cooling and heating rates of 0.1 K/min. The solidification and melting experiments were carried out at a mean air velocity of 0.837 and 0.833 m/s, respectively. The temperature differences between the peak phase change temperature and the mean air temperature are 20.87 and 17.21 °C, for solidification and melting, respectively. It was observed that melting occurred at a higher rate than solidification due to natural convection. Melting completes (3–12) minutes faster than solidification depending on the position of the sphere in the thermal setup. Because of the natural convection some deviations between the experimental and differential scanning calorimetry heating rates were observed. The experimental thermal storage is capable to reduce the air temperature with approximately (7.54-14.61) °C, at melting.

The study presents a preliminary numerical investigation on the thermal behavior of a ground buried cylindrical solar thermal energy storage tank, operating in a solar district heating network. The proposed analytical model is based on energy balance and on the finite difference method. Due to the symmetry of the system, the model was considered one dimensional. A thermal solar field and an auxiliary gas boiler were considered as the thermal energy sources of the investigated system. The system serves a residential area situated in Zaragoza, Spain, with 1000 dwelling considered as heat consumer. The hourly variation of the operating conditions with different solar radiation and different ambient temperature were taken into account. The mathematical model was validated by comparison with results available in the literature and was further used in a case study, to prove the capability of this simple mathematical model to correctly describe the thermal behavior of a real solar district heating system with seasonal storage and to correctly adjust the storage tank volume with the solar field size and with the heating load. The solar fraction of the investigated system was determined in the range of (55.66–64.5%) depending on the size of the storage tank.

This case study analyzes a cryogenic air separation unit (ASU) with a production of V˙O2=58,300[m3Nh] of gaseous oxygen with a concentration greater than 98.5%, operating in Romania on a steel plant platform. The goal of the paper is to provide an extensive model of exergetic analysis that could be used in an optimization procedure when decisional parameters are changed or structural design modifications are implemented. For each key part of the Air Separation Unit, an exergetic product and fuel were defined and, based on their definition, the coefficient of performance of each functional zone was calculated. The information about the magnitude of the exergetic losses offers solutions for their future recovery. The analysis of the exergy destructions suggests when it is worth making a larger investment. The exergetic analysis of the compression area of the ASU points out an exergy destruction and loss of 37% from the total plant’s electrical energy input. The exergy loss with the heat transferred to the cooling system of compressors can be recovered; for the exergy destruction portion, the challenge between investment and operating costs should be considered. The exergy destruction of the air separation columns found the High Pressure Column (HPC) to be more destructive than the Low Pressure Column. The share of the exergy destruction in the total plant’s electrical energy input is 8.3% for the HPC. The local COP of the HPC, calculated depending on the total exergy of the local product and fuel, is 62.66%. The calculus of the air separation column is performed with the ChemSep simulator.

Inulin, a natural polymer formed by several units of fructose and just one unit of glucose, is found in different plants or directly in some fruits or vegetables. Due to its structure it has been used in many applications from medicine, pharmacology or food industry. In spite of this, a complete vibrational analysis of the molecule is missing in the literature. Moreover, there are contradictory results regarding the assignment of certain vibrational modes. Therefore, the aim of this study was to obtain a comprehensive vibrational investigation of inulin by means of experimental (FT-IR and Raman spectroscopy) and theoretical (density functional theory -DFT simulations) methods.

The study provides novel and validated explicit equations of the apparent heat capacity variation with temperature for three phase change materials (PCM): RT20, RT25 and RT27. The developed models of PCM thermal behavior were successfully applied in the energy efficiency analysis of the fresh air cooling system with PCM latent heat storage system, serving a virtual office building considered to be located in different climatic conditions. Following the study, a practical guideline for estimation of the required quantity of PCM in fresh air cooling systems was provided. Two novel specific energy indicators were also proposed, which are useful for feasibility studies. The evaluation of PCM energy efficiency in fresh air cooling systems revealed that savings in the electric energy consumption of (7–41) % can be achieved, depending on the particular local conditions. Limits of the use of PCM in fresh air cooling systems were also provided.

Pig rearing on concentrate feed may not be economical because of higher market price of raw materials. The alternative source could be the use of swill feeding. Consequently, the impact of the swill feed on the backfat thickness and body measurements calls for investigation against any other alternative feed. Hence in the present study, an attempt has been made to compare the body measurements and backfat thickness in fattener piglets which were fed with swill feed (T1) vs. Those fed with chocolate cream waste supplemented with swill feed (T2). The statistical analysis of the data obtained in the present study revealed that there was highly significant (P?0.01) difference between body weight gain and backfat thickness (layer I and II) of both the group of piglets which were taken for trial starting from three months of age till five months of age. However, not significant difference (P?0.05) was noticed for body length and chest girth except in the pigs of 150 days age group. This study indicates that swill feed supplemented with chocolate cream waste could be used to reduce the feed cost since higher weight gain is achieved in a shorter time interval, increasing body measurements and backfat thickness compared to swill feed (T1) group of piglets.

Thermal energy storage tanks have a fundamental role in the preparation and simultaneous distribution of domestic hot water. These tanks are supplied with thermal energy via classical means, based on electrical energy and fuel combustion, and via renewable energy sources. This study investigates the possibility of reducing the storage tank’s accumulation volume by employing phase change materials to store high densities of thermal energy at constant temperatures. A mathematical model was developed to simulate the operation of storage tanks equipped with immersed solar coil, also taking into account the addition of phase change materials encapsulated in cylindrical containers. The mathematical model was validated based on literature data. The simulation program also determines the temperature of the primary heat transfer fluids, prepared by a solar collector system and a flat plate heat exchanger coupled with a gaseous fuel boiler. The program was used to study the performance of storage tanks that serve a public swimming pool, a type of building that is characterized by a high demand of domestic hot water. To the best knowledge of the authors, this scenario was not reported in the literature. The study revealed that the nominal volume of the storage tanks can be reduced by 25% in comparison to the classic alternative, by using phase change materials as thermal storage. Also, the tanks equipped with phase change material achieved a reduction of fuel consumption and CO2 emissions by (5.00-11.97) % in comparison to the classic solution.

The study presents a numerical analysis of the flow and heat transfer on a latent heat storage device based on a phase change material ( PCM ) encapsulated in spherical shells. This kind of heat storage system is designed for passive cooling in air conditioning applications by cold accumulation through the solidification of PCM during the night and by cold discharge through the melting of PCM during the day. The numerical analysis is taking into consideration both the PCM solidification and melting processes. The geometry of the analysed system was taken from an experiment available in the literature and the obtained results were compared with those of the experiment. The developed mathematical model proved to be capable to describe the flow and heat transfer in such systems.

The study presents a numerical investigation on operating conditions and performances of a solar absorption chiller with LiBr-H2O. The working cycle of the investigated solar cooling equipment was modelled based on thermodynamic principles by the use of the software platform Engineering Equation Solver and was validated based on similar studies reported in literature. Further it was investigated the influence of the operating conditions like solar hot water temperature, cooling water temperature and cold water temperature, on the coefficient of performance of the solar absorption chiller and on the conditions of crystallisation. The numerical model of the solar absorption chiller working cycle proved to be capable to describe the behaviour of the equipment and to evaluate the safe operating conditions from the crystallisation point of view and from degassing point of view.

The study presents the evaluation of a heat recovery system in a Romanian aluminum foundry. The study was based on a thermal power balance that revealed on one side that the components of the balance is in good agreement with similar results presented in the literature and revealed on the other side the heat recovery potential from the available waste represented by exhaust gases. The proposed heat recovery from waste is capable to recover more than 25% of the total thermal power of the burners, equivalent with more than 60% of the available waste.

This study presents the results of a 3 year experiment concerning the behavior of a geothermal ground-water heat pump used for heating a small residential house. The study is focused on the one side on the ground temperature variation around the horizontal collector oversized by ≈50%, mounted at 1.7 m depth and on the other side on the working conditions and performances of the heat pump itself. It was highlighted that due to the oversizing of the geothermal collector, the ground temperature did not drop below 2 °C and ground freezing was avoided. The ground temperature recovered each year during the non-heating season. The heat pump coefficient of performance was determined in the range of (3.18–8.59) in different operating periods.

The study carried out by simulation, concerns the thermal behavior of an office building’s solar fresh air cooling system, based on a LiBr-H2O absorption chiller in different climatic conditions. The coefficient of performance (COP) and the solar fraction were considered performance parameters and were analyzed with respect to the operating limits—the risk of crystallization and maintaining at least a minimum degassing zone. A new correlation between the required solar hot temperature and the cooling water temperature was established and then embedded in another new correlation between the COP and the cooling water temperature that was used in simulations during the whole cooling season corresponding to each location. It was found that—the solar hot water should be maintained in the range of (80−100) °C depending on the cooling water temperature, the COP of the solar LiBr-H2O absorption chiller with or without cold storage tank could reach (76.5−82.4)% depending on the location, and the solar fraction could reach (29.5−62.0)% without cold storage tank and could exceed 100% with cold storage tank, and the excess cooling power being available to cover other types of cooling loads—through the building envelope, from lighting, and from occupants, etc.

The study provides a comparative analysis of the energy production of a 3 kW peak PV array connected in an islanded microgrid, in correlation with solar radiation and ambient temperature measurements. The experimental system is located in Cluj-Napoca Romania and was monitored during the year 2017, based on a graphical user interface. It was also evaluated the capability to predict the PV energy production by using the PV*SOL simulation software and an analytical model, developed at the Technical University of Cluj-Napoca. As input data in the analytical model was used the measured solar radiation and ambient temperature while in the simulations was used alternatively measured data and average meteorological data available in the software database. Besides energy production it was compared the solar radiation on the tilted plane of the PV panels, the PV panel's temperature and the system efficiency. For the predictions accuracy evaluation it was used the weighted mean absolute error based on total energy production, which was found to be lower than 1%, in good agreement with the values reported in literature. The outcomes of this study are valuable for expanding the PV installations in this area and for predictive energy management developments.

This study performs an exploratory analysis of the evolution of consumption of RES for EU28 countries over the ten years studied. Through the analysis, the document presents: the consumption by sectors of production and by renewable energy sources, analyses the evolution of consumption from RES: between countries and regions. Regarding the consumption of RES, it is increasing, reaching in 2017 compared to 2008 to increase by 147.8%.

The study presents a complex evaluation of the indirect evaporation cooling technology potential to reduce the energy consumption of the fresh air conditioning system, of an office building in the climatic conditions of Cluj-Napoca, Romania. The study was realized for the cooling season of one year based multiannual values of ambient temperature and relative humidity. It was considered two types of fresh air conditioning systems. The classic system was considered composed of a cooling battery powered by an electric chiller and the evaporative system was considered composed by a recuperative heat exchanger, indirect evaporative cooling equipment and the same classic cooling battery. It was found that the fresh air cooling period starts in May and ends in September. The performances of the two air conditioning technologies were compared and it was concluded that the evaporative system allowed the reduction of energy consumption for the fresh air cooling with almost 80%.

s The paper presents a review of indirect evaporative cooling (IEC) operating conditions and performances. This cooling technology is promising to develop in the near future due to its very low energy consumption and high efficiency in its range of applications. The review is presenting in details: operating conditions and performances. Having very low energy consumption comparing to classic cooling, the IEC technology is environmental friendly and has very low global warming impact. The single disadvantage of IEC is the water consumption. The review also includes a study concerning the limits of IEC for different locations world-wide.

The paper presents actual knowledge concerning the indirect evaporative cooling (IEC). This cooling technology is promising to develop in the near future due to its very low energy consumption and high efficiency in its range of applications. The review is presenting in details: theory, working principles, flow and construction. The IEC equipment and technology is suitable in different air conditioning applications: commercial, industrial, residential or data centres. The IEC technology is completely environmental friendly and has very low global warming impact. The single disadvantage of IEC is the water consumption.

The study presents a numerical model that uses the enthalpy method in order to solve the moving boundary problem and to predict the thermal behaviour of phase change materials during solidification and melting. The commercially available paraffin RT21 is considered as phase change material, and the thermophysical properties of the paraffin were determined by differential scanning calorimetry. An inverse enthalpy-temperature function was determined based on the results of the differential scanning calorimetry measurements in order to model the phase change process. The model was experimentally validated, and good agreement was found between the computed and measured results.