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The paper mill which use recycled paper as the raw material generate paper mill reject (PMR) in the range of about 5-10%. PMR has a high calorific value with low ash and sulfur contents, generally. Processing of PMR into pellet forms as boiler fuel to reduce the use of coal or other fossil fuels has not been done, yet. PMR pellets and coal was mixed in the ratio of 5% PMR and 95% coal (C95R5) and 10% PMR and 90% coal (C90R10). PMR, coal, C95R5 and C90R10 were analyzed for proximate (moisture, ash, volatile matter/VM, fixed carbon/FC), and sulfur contents. Gross calorific value (GCV) of materials was also analyzed. Thermo-gravimetric analysis (TGA) and the derivative thermo-gravimetric analysis (DTG) profile were characterized. To know the possibility of slagging potential trend, analysis of ash mineral content and test of ash fussion temperature (AFT) of materials were carried out. Result indicates that addition of 5-10% PMR to coal affects combustion behaviour of materials. According to base/acid ratio (B/A) and base acid index (BAI) values, and softening temperature (ST) of slagging index, co-combustion of 5% PMR pellet and 95% coal (C95R5) as boiler fuel is still possible without causing indication of slagging tendency. [ABSTRACT FROM AUTHOR]

The present paper proves that the vast water supply infrastructure of Athens and the region of Attica could produce useful hydropower. The first aim of this paper is to present the unconventional small hydro philosophy of recovering the hydraulic energy wasted in the existing break pressure devices and energy dissipating structures of the Water Supply Network of Athens, the capital of Greece and of the whole Attica region. The paper discusses themes concerning the replacement, in this large drinking water infrastructure, of all the existing break pressure devices, by a series of small hydro plants and also the efficient ways by which such small unconventional hydro schemes could be realized. The second aim of the paper is to highlight some important CFD simulation features which however needs further investigations and to present preliminary some Flow-3D results concerning the hydrodynamic performances of this series of small hydro plants harnessing the important wasted hydraulic energy of the Attica Water Supply Network. [ABSTRACT FROM AUTHOR]

A new trend in energy systems planning through distributed energy systems has attracted increasing research attention worldwide. Through a comprehensive literature review, this paper presents the latest research and development in the field of distributed energy resource (DER) systems. The review identified five key areas of practice: Relevant concept, supply technology, modeling study, energy systems design, and policy assessment. DER systems offer a wide range of benefits and are linked to sustainable built environments. The paper discusses the applicability of the DER systems in the local energy system of a case study in Stockholm, Sweden. The paper describes a plan and system configurations involved in the search for energy supply options to achieve urban carbon-neutrality in the case study. [ABSTRACT FROM AUTHOR]

The existing of the High Voltage (HV) infrastructure creates a unique set of safety circumstances. The earthing system is one of the main elements to mitigate any unsafe conditions. Commissioning the earth grid certifies that the implemented system fulfills to the pertinent necessities. This paper endeavors to present vital information on how to perform the earth grid commissioning of an HV infrastructure. This paper will minutiae the minimum needs to guarantee the test will symbolize the actual fault case that the design was based on. A flow chart diagram is established and presented in this paper, which allows the determination of the most suitable injection route. The results of the case study are discussed, and the results are shown in this paper. [ABSTRACT FROM AUTHOR]

Due to rapid global population growth and urbanization, there is corresponding increasing demand for energy. This increasing demand has necessitated the need to explore alternative sources of energy. Besides the growing energy demand, issues of environmental protection and climate change have risen to the top of global politics, leading to increased interests in renewable energy sources. One of these renewable energy sources with very diverse applications is biogas. Biogas, like natural gas, can serve as cooking fuel, transportation fuel, and as source for electricity generation, making it a very versatile fuel. Biogas is produced from several organic feedstocks, using anaerobic digestion technology. The technology has not developed as expected in Ghana despite reported enormous feedstock potential mainly due to, lack of data on specific areas where feedstocks can be assessed and the corresponding specific biogas potential, among other reasons. This paper surveys specific areas across Ghana where the diverse biogas raw materials are concentrated. The paper also studies existing biogas technologies and their potential utilization in various economic sectors of Ghana where their application will have the highest socio-economic impact. Technical expertise and technology transfer options for the biogas technologies needed in Ghana were also assessed. The survey showed that the most common feedstock types, readily available in Ghana for anaerobic digestion are agricultural residues and food-processing residues, livestock manures, slaughterhouse wastes, municipal solid waste (organic fraction) and municipal sewage sludge. Agro-industries that process cassava waste, rice residues, palm oil residue, fruit processing waste and shea cake are the key agroindustries with very high biomass feedstock potential in Ghana. Each of the different feedstock surveyed showed methane potential in excess of 10,000,000 m³CH4 in each of the regions. The survey also showed that biogas plants in use in Ghana are either the small to medium scale (10 m³ to 100 m³) fixed-dome digester or the floating drum digesters and two functional industrial scale Upflow Anaerobic Sludge Blanket (UASB) plants and the Ccontinuous Stirred Tank Reactor (CSTR). Some economic sectors that will be impacted from the dissemination of biogas technology are agriculture, waste management, energy and climate change, health and social benefits such as job creation and improved well-being. The paper concludes that there are skills and expertise in Ghana to manage small to medium scale biogas digesters, but on the industrial scale, there exists limited expertise in the design, installation, operation and maintenance of the plants. [ABSTRACT FROM AUTHOR]

The paper aims at better understanding of the opportunities and potentials of the deployment of clean energy in the region of highest fossil fuel reserves in the world, the gulf cooperation council (GCC) states, by conducting a comprehensive analysis of the seventh sustainable development goal (SDG7) in the GCC states context including a detailed description of its targets, indicators as well as interrelatedness with the other SDGs. In line with that, the paper evaluated the renewable energy potential in the GCC states, its readiness to deploy and the constrains still to overcome. Analysis showed that GCC region has got a high potential of solar and wind energy, and good readiness for its deployment. The potential of solar energy resources in GCC states varies between 5.1 to 5.9 kWh/m² year. The average wind speed in GCC countries is between 3.5 -6 m/s, with the highest average of 6 m/s in Qatar and lowest average of 3.5 in Saudi Arabia. [ABSTRACT FROM AUTHOR]

The main purpose of this paper is modified the strength and fatigue characterizations of natural rubber materials by reinforcement with Nano particle materials. Where the Nano particle used is carbon Nanoparticle tube with various volume fractions, as (0.2% to 1%). Therefore, the strength on rubber materials, with various Nanoparticle volume fractions, is evaluated by using experimental technique by testing the tensile sample with universal test machine. After this, evaluate the fatigue characterizations of rubber materials, with various Nano particle volume fractions, by two techniques, first, experimental technique with manufacturing the fatigue test sample and then using rubber fatigue machine to testing its samples to evaluating the fatigue strength and life, and second, numerical technique by using finite element method with using Ansys program technique. Where, the experimental results of fatigue characterization are comparison with numerical fatigue results to shows the agreement between experimental and numerical technique. Therefore, its comparison shows the good agreement of fatigue results with maximum error between the two techniques use is about (10.28%). Finally, the results for strength and fatigue are shown that the strength and fatigue characterization are modifying with reinforcement by Nano particle carbon materials. Then, the increasing of Nano particle is lead to increase the strength and fatigue characterizations of natural rubber materials. [ABSTRACT FROM AUTHOR]

The objective of this paper is to conduct an energy analysis of the Frontier Project using computer-based software and to verify results using load calculation spreadsheets. The Frontier Project is a demonstration of sustainable and renewable energy technologies [1]. The current paper serves to quantify the building energy demands by performing a building energy load calculation on the facility. This is meant to act as a case-study of how energy and the environment can be influenced by using and promoting the correct technologies. The computer-based software selected for use was eQUEST [7] version 3.65. The ASHRAE Bin Method was used to validate the eQUEST computer model. The methods are found to agree with 20% shown that the overall load is 20 tons or 70.34 kW for the 1759.2 m² facility. [ABSTRACT FROM AUTHOR]

Renewable energy is becoming an essential element when it comes to climate change. The advance technology in energy storage increases the installation of standalone system for residential houses. As the solar system is the sole power source for the property, a rigid reliability system should be designed. The paper addresses the earthing requirement for the standalone system to mitigate lightning strike, transfer voltage from nearby high voltage infrastructure and adequate protection operation. Case study is also included. [ABSTRACT FROM AUTHOR]

The optimal performance of an irreversible quantum Carnot refrigerator with working medium consisting of many non-interacting harmonic oscillators is investigated in this paper. The quantum refrigerator cycle is composed of two isothermal processes and two irreversible adiabatic processes, and the irreversibilities of heat resistance, internal friction and bypass heat leakage are considered. By using the quantum master equation, semi-group approach and finite time thermodynamics (FTT), this paper derives the cooling load and coefficient of performance (COP) of the quantum refrigeration cycle and provides detailed numerical examples. At high temperature limit, the cooling load versus COP characteristic curves are plotted, and effects of internal friction and bypass heat leakage on the optimal performance of the quantum refrigerator are discussed. Three special cases, i.e., endoreversible, frictionless and without bypass heat leakage, are discussed in brief. [ABSTRACT FROM AUTHOR]

The finite time exergoeconomic performance of the generalized irreversible Carnot heat engine with the losses of heat resistance, heat leakage and internal irreversibility, and with a complex heat transfer law, including generalized convective heat transfer law and generalized radiative heat transfer law, q ∝ (ΔTn )m , is investigated in this paper. The focus of this paper is to obtain the compromised optimization between economics (profit) and the energy utilization factor (efficiency) for the generalized irreversible Carnot heat engine, by searching the optimum efficiency at maximum profit, which is termed as the finite time exergoeconomic performance bound. The obtained results include those obtained in many literatures and can provide some theoretical guidelines for the design of practical heat engines. [ABSTRACT FROM AUTHOR]

The first aim of this paper is to present data concerning the design, construction, installation and operation of the first in the world Horizontal Axis Archimedean Screw Turbine (H.A.A.S.T.), having a length L=1m, diameters (output and input) Do=200mm and Di=100mm, a pitch S=200mm and a number of blades n=3. This horizontal screw could rotated horizontally and change direction (Δθ = 100°), forming an upstream angle of 50 ° with its initial position and a downstream angle of 50 ° with its initial position. The second aim of the paper is to present experimental results of the operation in a big hydraulic channel under various controlled conditions, simulating the operation of the physical conditions of rivers, open channels, etc. The third aim of the paper is to present a series of theoretical performance prediction results based on various S1/S2 algorithms and Linear Actuator Disk simulations. [ABSTRACT FROM AUTHOR]

The Lagrangian particle tracking provides an effective method for simulating the deposition of nanoparticles as well as micro-particles as it accounts for the particle inertia effect as well as the Brownian excitation. However, using the Lagrangian approach for simulating ultrafine particles has been limited due to computational cost and numerical difficulties. The aim of this paper is to study the deposition of nano-particles in cylindrical tubes under laminar condition using the Lagrangian particle tracking method. The commercial Fluent software is used to simulate the fluid flow in the pipes and to study the deposition and dispersion of nano-particles. Different particle diameters as well as different pipe lengths and flow rates are examined. The results show good agreement between the calculated deposition efficiency and different analytic correlations in the literature. Furthermore, for the nano-particles with higher diameters and when the effect of inertia has a higher importance, the calculated deposition efficiency by the Lagrangian method is less than the analytic correlations based on Eulerian method due to statistical error or the inertia effect. [ABSTRACT FROM AUTHOR]

In this paper, the authors aims to introduce Uranium contamination in Al Tuwaitha nuclear site using Geomatics techniques. The contamination level of Uranium (235, 238, 234), from different soil samples of the nuclear reactor surrounding areas has investigated and compared to the international standards of UNSCEAR 2000,. The results show that distribution indicates a relatively asymmetrical distribution tailing slightly towards higher concentration. However, the activity level of Uranium in the soil samples exhibits higher variability. U238, 235,234 concentration level exceed the permitted level by (75) times over the UNSCEAR (2000) regulation in spot near Ishtar village and many other uranium contamination inside Al Tuwaitha nuclear research center, location C and Ishtar village. The contaminated area above normal concentration of U sum in soil having about 65% from total contaminated area (0.87 km2) between (0.08-0.2) Bq/g, 23% between (0.2-0.4) Bq/g, 6% between (0.4-0.7) Bq/g, 5% between (0.7-2.5) Bq/g and 1% between (2.5-4.5) Bq/g as the highest concentration level. [ABSTRACT FROM AUTHOR]

The chemical-looping with oxygen uncoupling (CLOU) has been demonstrated to be an effective technological pathway for high-efficiency low-cost carbon dioxide capture when particulate coal serves as the fuel. In this paper, complete process-level modeling of CLOU process conducted in ASPEN Plus is presented. The heat content of fuel and air reactors and air/flue gas heat exchangers is carefully examined. It is shown that the established model provides results which are in excellent agreement with the experiments for the overall power output of the CLOU process. Finally the effect of varying the air flow rate and three different types of coal as the solid fuel on energy output is investigated, and the performance of three - Copper (Cu), Manganese (Mn) and Cobalt (Co) based oxygen carriers in CLOU process is compared. It is shown that there exists an optimal air flow rate to obtain the maximum power output for a given coal feeding rate and coal type. The effect of three different oxygen carriers on energy output is also investigated using the optimal air flow rate. Among the three oxygen carriers - CuO, Mn2O3, and Co3O4; Mn2O3 shows the best performance on power output. The results presented in this paper can be used to estimate the amount of various quantities such as the air flow rate and oxygen carrier (and its type) required to achieve near optimal energy output from a CLOU process based power plant. [ABSTRACT FROM AUTHOR]

The study evaluates the development of national supply security. The aim of the paper was to examine the supply security of solid domestic fuels for Finnish combined heat and power plants (CHP) in a domestic fuel disruption. The consumption of wood fuels has increased in recent decades and discussion of supply security has become important nationally. On the other hand, the consumption of peat and coal has been replaced by biomass, which has created questions over its sustainable availability regionally and nationally. The study utilised a questionnaire targeting major combined heat and power plants utilising domestic fuels located around Finland. The response rate of questionnaire was as high as 88%, which reflected the importance attached to the subject. The most significant concern was that economical operating conditions for peat should be ensured, or wood fuels will face difficulties in securing the energy supply by itself. However, the CHP plants were prepared to increase the use of wood fuels, for example by developing logistical systems, investing in fuel terminals and intensifying cooperation with fuel suppliers. Topic of the study is also important internationally. [ABSTRACT FROM AUTHOR]

This paper presents a short view of the first Archimedean Screw Turbines CFD modelling results, which were carried out within the recent research entitled "Rebirth of Archimedes in Greece: contribution to the study of hydraulic mechanics and hydrodynamic behavior of Archimedean cochlear waterwheels, for recovering the hydraulic potential of Greek natural and technical watercourses". This CFD analysis, based to the Flow-3D code, concerns typical Tubular Archimedean Screw Turbines (TASTs) and shows some promising performances for such small hydropower systems harnessing the important unexploited hydraulic potential of natural and technical watercourses of Greece, of the order of several TWh / year and of a total installed capacity in the range of thousands MWs. [ABSTRACT FROM AUTHOR]

This paper presents a study on the vibration characteristic of open edge cracks graded moving shear beam. The material property gradient is based on the distribution of the power-law in the direction of the beam thickness. The vibration equation is obtained depending on the precept of Hamilton principle and resolved by the extension of Galerkin's approach. To represent the cracking in the beam, a rotational spring is used. The effects of the axial velocity, gradient index, and cracking parameters on vibration characteristics are observed. Furthermore, the shapes of the model are determined for simply supported cracked moving graded shear beam. The results show that the natural frequencies decrease with the rise in the axial velocity, the crack depth, and the material property index. The percentage of decrease in the natural frequencies as a result of increase in crack depth ratio is 40%. [ABSTRACT FROM AUTHOR]

Bone and blood are the most implanted tissue. The collagen and substituted hydroxyapatite are major solid components of human bone. In the present study, a modest attempt has been tried to use a different method. The techniques involve the coating materials (collagen and hydroxyapatite) and the base materials Ti alloy. The aim of the paper to use spin method to coating Ti6Al4V alloy with HAp (1, 2, 3) g + (0.5 collagen) The X-ray diffraction test results show nano-size crystal structure on the coated film. By Increasing in concentration of HAp leads to an increase in thickness of film, (25-40) µm and that is clear in the results of scanning electron microscopy SEM and optical microscopy. From SEM results, the aggregation HAp nanoparticles are confined to their nano size. Also collagen with graded porosity, the mean diameter of pore in nm this type of scaffold can be used to tissues that belong to the success of the solution preparation method and use spin coating method. [ABSTRACT FROM AUTHOR]

The present paper describes the evaluation of the Greek Archimedean Small Hydro Resources, considering the basic data for the 14 water regions of the country, adopting a holistic assessment methodology of the total theoretical hydro potential of Greece, which could be exploited by using Archimedean Screw Turbines (ASTs). The total evaluation of the theoretical Archimedean hydropower potential of Greece, which may be produced with ASTs, is of the order of several TWh / year, with a theoretical installed capacity of screw turbines in the range of thousands MW, with important values of special capacity and special capacity density, demonstrating the major existing unexploited hydropower potential for a future true sustainable development with small hydro plants in Greece based on environmentally friendly screw turbines. [ABSTRACT FROM AUTHOR]

Since the invention of lithium ion batteries, charging strategies have met great acknowledgment and research over the years. In this paper, a laptop with lithium polymer battery is monitored via three widely used tools, during various operational and charging loads. Several key values are obtained in order to evaluate the correlation between battery cycles, charging percentages and depth of discharge. Ultimately the results show that massive discharges and continuous operation with the device plugged should be avoided, though high load tasks require the AC charger to be connected. Ensuring that battery stays at safe temperature and charging ranges can expand cell life and state, as well as prevent lithium deposits inside the battery. [ABSTRACT FROM AUTHOR]

Agriculture is a significant user of water and energy in Mediterranean coasts of Europe, such as Spanish Mediterranean regions. Water implications of such irrigations are well known, but also energy must be considered when environmental implications are analyzed. Apart from this, Mediterranean region has its particular problematic framework related to irrigation issues. Often, the availability of irrigation is determinant to the viability of farmers, and the energy implications must be considered when determining the feasibility of small and big farms, particularly in the Mediterranean regions, where the wide variety of customs in each group of irrigators and definitely, its specific weather conditions, typical of a semi-arid zone. All these aspects are analyzed in this paper, as a state of the art determination of problems and possible solutions in a regional scale. Some solutions presented in this paper can contribute with theoretical reductions of emission of greenhouse gasses until 174.10 tCO2/year in pumped systems and 58.49 tCO2/year in multipurpose systems. [ABSTRACT FROM AUTHOR]

Calcium looping (CaL) is a recent technology that utilizes calcium oxide (CaO) and the carbonationcalcination equilibrium reactions to capture carbon dioxide (CO2) from the flue stream of fossil fueled power plants. In this paper, system level simulations are developed in Aspen Plus to calculate the energy penalty of introducing calcium looping in a coal fired power plant. Both post-combustion and precombustion capture scenarios are investigated. The relationship between various flow ratios, the conversion rate of CaO, and the carbon capture efficiency is used to validate the Aspen Plus model for the calcium looping process; it agrees well with the experimental data and simulation results available in the literature. The simulation shows an increasing marginal energy penalty associated with an increase in the carbon capture efficiency, which limits the maximum carbon capture efficiency in real-world applications of calcium looping to between 95% and 98% before the energy penalty becomes too large. [ABSTRACT FROM AUTHOR]

The study presented by this paper is intended to estimate the daily solar irradiation under real-sky condition for Braşov (Romania) area. To this end, it is presented the methodology that was led to determine the estimation regressions of daily solar irradiation and the results of meteorological data sets processing. It is also performed an analysis of the variation of some climatic parameters specific to the analyzed area as, the sunshine fraction, the sky ratio and the Perez's clearness index, in order to identify the possible sources of error and to assess their impact on accuracy of estimation models for daily solar irradiation. Special attention has been given to the analysis of statistical indicators that were the basis for performance analysis of the obtained models; focusing on optimizing the Pearson's coefficient, this paper presents the monthly regressions for two estimation models of daily global irradiance and corresponding to these, four estimation models of daily diffuse irradiation. [ABSTRACT FROM AUTHOR]

This research presented isotropic hyper composite plates structures, which are made of (resin and fiber with powder as a reinforcement material). The basic item of this research is to improve the dynamical properties of the composite structure. This item has been verified by adding the powder as a reinforcement material. Square and rectangular hyper composite plates (AR=1 and 1.5) are made with different volume fractions for glass powder, resin and short fiber. Different boundary conditions are used (SSSS, CCSS, CCCC, CFFF, SSFF and CCFF) to support these plates. The dynamical properties of hyper composite models are calculated numerically with considering these different parameters. The results showed that the natural frequency increases by increasing the volume fraction of powder or short fiber with decreasing the resin. It can be concluded that the fundamental natural frequency in aspect ratio (AR=1) increased successively with the boundary conditions (CFFF, SSFF, SSSS, CCFF, CCSS, and CCCC) in ascending order, because the increasing in stiffness of the composite plate depends on the supporting conditions. And, for aspect ratio (AR=1.5), the fundamental natural frequency is increased successively with the boundary conditions (CCFF, CFFF, SSFF, SSSS, CCSS, and CCCC) in ascending order. Also the results showed that the fundamental natural frequency of aspect ratio 1 is larger than 1.5, because the ratio between stiffness to weight for AR=1 is larger than AR=1.5. A comparison made between present numerical results and results presented by former published paper Abdulkareem et.al. [8] and theoretical results by Muhannad Al-Waily [9] for simply supported plate with aspect ratio (AR=1, a=b=25 cm and h=5 mm) and different volume fractions of resin, powder and short fiber and good agreement were the maximum error between numerical and experimental is results is about 5.73% (with 20% short reinforcement fiber, 30% powder reinforcement and 50% resin materialswhile the maximum error between numerical present results and theoretical results; Muhannad Al-Waily, [9] is about 12.86% (with 30% short reinforcement fiber, 20% powder reinforcement and 50% resin materials). [ABSTRACT FROM AUTHOR]

Fluid conveying pipes are used in all hydraulic systems and enter in all industrial fields, such as water, petroleum products and gases of all kinds. In spite of this widespread and critical importance of fluid conveying pipes, they suffer from major problems. One of these problems is the problem of vibrations that cause the collapse of the systems completely and cause significant economic losses if not avoided. For this reason, the researchers have dealt with this issue in all years, but the problem is not over. This research will highlight the problem of controlling the vibrations resulting from fluid flow inside the pipes, in addition to the study of reducing the vibrations of these pipes. Therefore, after investigation the control and stability for pipe with various methods, with previous papers, presenting in this paper investigation for active control for pipe by using Nyquist's method. There, the research has studied the response and the natural frequency; the dynamic behavior of conservative and non- conservative pipes conveying fluid using Nyquist's Theorem in the presence with no hydraulic damping (active control); and monitoring the response and stability of each case of stabilization. This study is carried out by deriving differential equations for pipes and for different types of fixation. Where, the analytical solution included drive the general equation of motion for pipe conveying fluid and then solving its equation by using Galerkin's technique, and then, calculating the stability by using Nyquist's techniques. [ABSTRACT FROM AUTHOR]

The problem of vibrations cause the collapse of the systems and cause significant economic losses if not avoided. For this reason, the researchers have dealt with this issue in all years, but the problem is not over. In this paper will highlight the problem of controlling the vibrations resulting from fluid flow inside the pipes, in addition to the study of reducing the vibrations of these pipes. The ideal control is designed based on, the state space theory and according to the linear behavior of time, because the stability of the pipes are found from linear change. Different factors were studied on the controller's performance and then the optimal factors were obtained to obtain the best performance. The research included the study of the response and the natural frequency and the study of the dynamic behavior of different types of stabilization of the pipes in the presence with no hydraulic damping (active control) and monitoring the response and stability of each case of stabilization. Where, the control investigation include using the analytical solution of general equation of motion for pipe by using state space technique. There, the parameters studied for active control pipe vibration included the effect of hydraulic damper position, base width of hydraulic damper, damping, and the flow Pressure, on the pipe vibration response, with various pipe boundary conditions supported. [ABSTRACT FROM AUTHOR]

This paper entails a computational investigation that aims to examine the effects of applying Phase Change Materials (PCM) and fins as a cooling technology for the Photovoltaic (PV) panel system in arid areas. In previous case studies, it is noticeable that PCM heat transfer showed to be a weak point, therefore, the focus of this investigation is to enhance the efficiency of the heat transfer between PCM and the ambient atmosphere by applying fins on the container of PCM. Enhancing the heat transfer helps PCM to remain in its transitional phase, which allows PCM to absorb latent heat (LH). The findings of this paper show the effects of combining PCM and fins, evidencing that it decreases the temperature of the PV panel's surface temperature around 7 K for a heat flux and the ambient temperature of 750 W/m2 and 318.15 K respectively. [ABSTRACT FROM AUTHOR]

The removal of molar denture was made from PMMA polymer. The alternating load of dental during the process of chewing food therefore it is failure by fatigue. In fatigue failure the crack was initiate then crack propagate. In this paper, the effect of repeated load on life of removable molar denture was study, the PMMA molar was manufacturing then testing to determine mechanical properties by compression fatigue load tester. Also, the mechanical properties of the material were examined as a test of compression and hardness. The force of load is find by special sensor. Finally, the repeated load on removable dental molar can be reduce the life of the dental to less than half. [ABSTRACT FROM AUTHOR]

In this paper, different mathematical models 3D case are investigated and comprised in order to assess the accuracy of these models under different conditions of terrain topography depend on Geomatics methods. Three high resolution satellite QuickBird images (panchromatic 0.6 m in spatial resolution) of three different study areas, with respect to their topography (a flat area, a hilly area and a mountain area) in Iraq have been used in this work. The flat area is chosen in Baghdad in the middle of Iraq while, the hilly and mountain areas are chosen in Irbil in the north of Iraq. The 3D mathematical models which were used, 1st, 2nd order 3D polynomial, and direct linear transformation model. All these methods are applied for each study area and evaluated through the Matlab environment facilities. The results of 3D models in the three studied areas indicate that the best accuracy is achieved with 2nd order 3D polynomial and DLT models while the worst accuracy is obtained with 1st order 3D polynomial model. Therefore, in the case of using 3D models, the 2nd order 3D polynomial and DLT models is recommended to achieve high geometric accuracy. [ABSTRACT FROM AUTHOR]

In this paper, the effect of different types of stiffeners on the cylindrical shell structure is investigated. The dynamic properties (natural frequencies and damping ratio) were computed for each finite element models. Finite element models for the different steel cylindrical stiffened shell have been created by considering helix angle, numbers, locations and height of stiffeners with a constant mass which is (4 kg), and a cantilever supported structures are used. An experimental test has been done to check the validity of the stiffened shell model. The results obtained are the natural frequency and damping ratio. A comparison between the natural frequency and finite element result is made with an error (18.43%) is found. Modal analysis is performed to each finite element models to extract the values of the naturl frerqunis. The mode l of (helix angle = 67 .5­ height = 3.125cm, internal and eight stiffeners) have the highest value of the natural frequency when compared with the other models. Finally, a comparison between experimental work of M. Bagheri and A.A. Jafari [1] and numerical part of the current paper has been occurred with a small percentage error between them. [ABSTRACT FROM AUTHOR]

In this paper, titanium dioxide (TiO2) nano-particles were synthesized by the sol-gel method by using Titanium tetrachloride (TiCl4) solution as precursor. The effects of calcination temperature were determined. The samples were examined using X-ray diffraction (XRD), scanning electron microscope (SEM) and Fourier-transform infrared spectroscopy (FT-IR) analysis. X-ray diffraction measurements showed that TiO2 nano-particles were polycrystalline with rutiles and anatase phases. The Surface morphological studies obtained from SEM micrographs. Particle size increased from 43 to 500 nm when calcination temperature was 500 °C. In the FT-IR spectra, the peaks observed below 700 cm-1 due to stretching and bending vibrations of Ti-O-Ti bond. [ABSTRACT FROM AUTHOR]

Pipes conveying fluid have many uses and the danger increases as the fluid is more likely to burn in the event of contact with the atmosphere, especially in oil installations. Many of the problems occurred due to the erosion and corrosion caused large explosions and many losses. For example, the fire and explosion in Chevron Richmond refinery in California. From this example and others, the idea of detecting erosion was introduced using vibration sensors. In this paper, proposed by the researchers an experimental method for detecting chemical corrosion and erosion caused by the flow of fluid inside the pipe in addition to the effect of external conditions in Al-Najaf Refinery. The examination was carried out by followed pipe (154.06mm) internal diameter, (168.28mm) external diameter and (7.11mm) thickness. The pipe specifications were ASTM\ASME A106 Grade B Sch40, 210Mpa modulus of elasticity and 7.85×10³Kg/m3 density. The pipe conveying RCR fluid and fixed with simply-supported ends. The focus was on a 10-meter pipe length. Also, the thickness of the pipe measured by Ultrasonic Thickness Gauge, and the frequency measured by Digital Vibration Meter, and the fluid velocity measured by Ultrasonic Flow-meter. The required values were examined every three months within five years in the same velocity and by keeping it within the limits of laminar flow. By followed up and studied the draw diagrams to find the search results, it has been shown that decreasing the thickness of the pipes over time due to erosion corrosion gives an increase in the frequency of the pipe transmitted fluid. This was evidence of the possibility of getting an indicator of erosion and corrosion through the pipes vibration. Where, the sensitivity of the frequency increase was indicated by the decrease in the thickness of the pipe due to the erosion and corrosion of the pipe wall. The percentage increase of frequency between the standard pipe without erosion and corrosion and the pipe after 5 years is 3.91%. [ABSTRACT FROM AUTHOR]

This paper presents a techno-economic analysis of hybrid renewable energy systems (HRES) to supply the electrical load requirements of the Central Library of Kırklareli University located in Kavaklı Campus, Kırklareli, Turkey. The standalone and grid connected HRES (Grid/PV/battery, wind/battery and PV/wind/battery etc.) considered in the analysis were comprised of different combinations of PV modules and wind turbines supplemented with battery storage. Meanwhile, wind and solar energy potential in Kırklareli is fairly appropriate for supplying energy requirements of some places with no high electricity load like libraries. In this study, the HOMER software is used as the assessment tool to determine the optimal configuration of HRES taking total net present cost (NPC) and cost of energy (CoE) into consideration. As a result, it is determined that the optimal system configuration of standalone hybrid system with the lowest total NPC consists of 40kW PV array, 10kW Wind turbine, 20kW power converter and 72 batteries and also that total NPC and CoE of the optimal configuration are estimated to be $228,330, $0.334/kWh, respectively. Similarly, it is determined that the optimal system configuration of grid connected hybrid system with the lowest total NPC consists of 30kW Wind turbine, 100kW Grid and also that total NPC and CoE of the optimal configuration are estimated to be $137,979, $0.185/kWh, respectively. When these configurations are compared considering CoE and total NPC it is clearly shown that Grid connected hybrid systems is more economical than standalone hybrid system. But some environmental effects (CO2, CO NOx and carbon tax etc.) are taken into consideration the standalone hybrid system must be preferred. [ABSTRACT FROM AUTHOR]

Dynamic behavior of cracked functionally graded (FG) pipe conveying fluid lying on visco-elastic foundation is investigated in this paper. The crack is demonstrated as a massless torsional spring. The properties of the material are changed constantly across the micro-pipes thickness and depend on power law distribution. Efficient numerical procedure by Galerkin's method is developed to find the natural frequencies and stability for cracked FG pipe. The effects of cracks location, depth of crack, gradient index, and foundation parameters in FG pipes conveying fluid with certain flow velocity on frequencies are investigated. The present method is carefully checked by comparing their results for cracked pipe conveying fluid with the available results in literature. From the comparison, a reasonable agreement was found (i.e. the maximum discrepancy percentage was 1.5%). The results indicated that the fundamental natural frequency decreased due to the crack presents. Also, the flow velocity for FG pipe increased with gradient index increasing. [ABSTRACT FROM AUTHOR]

The objective of this paper is to design and analyze a naturally ventilated photovoltaic-thermal (PV/T) air collector numerically and experimentally in both glazed and unglazed conditions. To reduce the panel's temperature, a thin metal sheet in the middle of the air channel is used to improve thermal and electrical output of the system. A good agreement is first achieved between the numerical results and the measured data. The validated model is then used to evaluate the effective parameters i.e. solar radiation intensity, channel depth and channel length on air mass flow rate, PV cooling, outlet air temperature as well as thermal and electrical efficiencies. The results show that while the thermal efficiency ranges between 12.21-37.17% throughout the day, the electrical efficiency ranges between 3.23-8.12%. [ABSTRACT FROM AUTHOR]

This paper aims to investigate and quantify the effect of changing the crest length of a piano key weir on its discharge coefficient. Empirical equation relating the discharge coefficient with the crest length has been developed based on dimensional analysis by means of statistical computer software. Data were gathered by physical modeling of five 2-unit piano key weir models in an experimental flume 15 m long, 0.3 m wide and 0.45 m deep. Results showed that increasing the crest length has a major influence on the discharge capacity that may reach as much as 100%. The empirical equation estimates the value of discharge coefficient in terms of the dimensionless ratio of (crest length to the weir width), as well as the ratio of (total head to the weir height). It has showed good agreement with experimental results. [ABSTRACT FROM AUTHOR]

Soil erosion is one of the most important natural resources management problems in the world and the source of sediment that pollutes streams, fills reservoirs, and causes dramatic impact to the aquatic ecosystem. Urbanisation is one of the significant agents of sediment generation due to soil disturbance and rainfall events. To capture the sediment generated from the construction before impacting the surrounding environment, a well-designed sediment basin is required. The use of knowledge-based systems has been significantly recognized as a way to combine scientific understanding of the process of the natural world with the heuristic rules developed by managers through observation and experience. In this paper, a rulebased decision support system has been developed for designing the dry and wet sediment basins for Malaysian construction sites using Visual Basic Tool. The design which is based on local studies and guidelines includes sizing the basin, sizing of emergency spillway, calculating the sediment basin trapping efficiency and maintenance frequency for both of the dry and wet basin. Preliminary validation, field validation and Turing test were applied for validating the developed system in which the results from this study showed that both of the system and the expert's opinions are almost matching which denotes that the system is intelligent and behaves like a human expert. The system can be considered as a "green technology" tool since it minimizes environmental impact. [ABSTRACT FROM AUTHOR]

A Fault Detection and Isolation (FDI) system for proton exchange membrane fuel cell (PEMFC) has been presented in this paper. Artificial Neural Network (ANN) is used to detect the faults. An Input\output data set have been acquisitioned from PEMFC and used to design an ANN model. The model designed gives a steady state prediction for a given input. The output of the PEMFC is compared to the output of the model, then a residual signal is monitored and used to detect the faults. Three types of faults have been studied in the presented work, which are: Abrupt, Incipient and Intermittent faults. The steady state model designed and simulated using Matlab. Then the ANN model has been downloaded to a hardware platform which is Spartan3 starter FPGA kit. The challenge of this study is to convert the FDI system to VHDL code to be downloaded to the FPGA. Due to the hardware limitation, the performance decreased by 5% and using an advanced features FPGA kit could remove that limitation. [ABSTRACT FROM AUTHOR]

Hydrothermal carbonization (HTC) is a thermochemical pretreatment process suitable for the valorization of biomass. It emulates the natural coalification and its main product, hydrochar, is a solid carbon-rich product that has a calorific value similar to that of lignite. The relatively low reaction conditions, the capability of the process to handle organic materials with high moisture content and the appealing properties of hydrochar render HTC a highly promising field. However, the reactions that take place are complex and partially understood. Several attempts have been made to develop reaction kinetics schemes in order to model the carbonization of specific types of biomass. In the present paper, two proposed models are examined and suggestions are made for the advancement of the process. [ABSTRACT FROM AUTHOR]

Polymer matrix composite structures can be exposed to a variety of severe corrosive environments during their service, which lead to degrade their structure and deteriorate their properties. The both influence of the alkaline and acid solutions on the mechanical properties of the hybrid polymer composite materials are illustrated in this paper. Hardness, tensile properties and impact strength of the nano-silica particles reinforced (glass/Kevlar) fabrics polyester hybrid composite before and after immersing in (HCl) and (NaOH) solutions studied. Regardless of the solution, hardness, tensile and impact strength decrease with increasing the exposure time. On the other hand, the alkaline solution led to high decreasing in these properties than the acid solution. In addition, the hybrid composite showed remark enhanced in the mentioned properties than the glass fiber polyester alone. [ABSTRACT FROM AUTHOR]

Low carbon steels wide range using materials, chemical composition and physical properties controls by using heat treatment process that including heating and then cool by appropriate quenching mediums. The effects of polyethylene glycol diluted with water as quenching medium on the mechanical properties (hardness, compression) and microstructural properties of low carbon steel were investigated with the aim at improving their compatibility with polymer quenching. The tested samples were prepared and subjected to heat treatment process used electrical resistance furnace soaked for 1 hour and then quenched in polyethylene (PE) diluted with water in controlled percentages of PE% (25%, 35%,45%). Used digital microhardness and universal test machine resulted an enhancement in their mechanical properties, they though (PE) gives good cool rates. The dominant of martensitic phase in microstructures resulting in their enhancement of low carbon steel properties. The hardness improvement about 83.5% as illustrated with this paper, also the compressive strength improved about 23.3% with this work. Also, an enhancement of surface cracks was observed with increasing (PE) percentage. It is assumed that polyethylene solution will help to develop high performance of low carbon steel properties for industrial fields applications. [ABSTRACT FROM AUTHOR]

The dynamical behaviors of pipes containing pulsating fluids are nonlinear. In such nonlinear systems principal regions of dynamical instability can result from the effect of the periodic excitation of the fluctuated fluid flow. Evaluating the boundary frequencies for these types of instabilities had been carried out by many analytical and numerical methods. In this paper, an approximate "closed-form" solution for evaluating the principal boundary regions of instability for conservative pipes conveying pulsated fluid has been attempted. Bolotin's method was employed to split the boundaries from the stable regions. The resulting coupled-ordinary differential equations is decoupled by neglecting the effect of the mass ratio term and solved analytically. After imposing the specified boundary conditions, then the simplified formulas or transcendental equations were obtained for the pipes under consideration. These equations can give the principal boundary regions in term of the system parameters by simple calculations. The present solution was carefully checked with the "exact" solution where the mass ratio was included. The results showed good agreement for pinned-pinned clamped-pinned and clamped-clamped pipes conveying pulsating fluid. [ABSTRACT FROM AUTHOR]

A combined cooling, heating and power plant (CCHPP), composed of an endoreversible closed Brayton cycle and absorption refrigerator, is studied in this paper. By introducing the finite time thermodynamics, the formula of the exergy output rate (EOR) of the CCHPP is derived. With the help of Powell arithmetic, the compressor pressure ratio of the Brayton cycle and distributions of 7 heat exchanger heat conductances (HEHCs) are optimized and the maximum EOR of the CCHPP is obtained. It shows that the hot-side HEHC is the largest one among the discussed HEHCs and several parameters, such as the total HEHC and ratio of heat reservoir temperature to the surrounding temperature, on the optimal performances of the CCHPP are analyzed. [ABSTRACT FROM AUTHOR]

A thermodynamic model of a steady-flow endoreversible Lenoir heat engine cycle (a "three point" cycle) coupled to constant-temperature heat reservoirs is established in this paper by using finite time thermodynamic theory. The cycle consists of one isochoric heating branch, one adiabatic expansion branch and one isobaric cooling branch. The analytical formulae about power output and thermal efficiency of the cycle are derived. The optimal performance of the cycle is obtained with the fixed total thermal conductance of heat exchangers. Moreover, the effects of the heat reservoir temperature ratio and the total thermal conductance of heat exchangers on the general and optimal performances are analyzed. The results show that the power and efficiency performance curve of the cycle is a fixed "point" with constant thermal conductance of hot- and cold-side heat exchangers, and there exist optimal thermal conductance distributions, which lead to maximum power and maximum efficiency, respectively, with changeable thermal conductances of hot- and cold-side heat exchangers. Both the power and efficiency will be enhanced with the increase of thermal conductance ratio between high- and low-temperature heat reservoirs, or the total thermal conductance of heat exchangers. [ABSTRACT FROM AUTHOR]

A two-stage model for the optimal planning of distribution systems with the presence of photovoltaic generation system (PV) is presented in this paper. The proposed model can determine the optimal sizing and timeframe of the equipment (feeders and transformer substations) in distribution systems. Therefore, the optimal displacement, sizing, technology and installation period of PV are also determined. The objective function is minimizing the life cycle costs of the planning project. The technical constraints are used to guarantee the operability of the distribution system including AC power flow, feeder and substation upgrading section, limited of nodal voltage and PV capacity. The binary variables are also employed in the model to represent the cost function of the equipment as well as the investment and upgrade decisions. The algorithm is programmed in GAMS environment. The feasibility and effectiveness of the proposed model are examined in a 7-bus test system. [ABSTRACT FROM AUTHOR]

The vibration characteristic of a cracked porous graded moving plate based on a neutral surface plane under uniform temperature rise is investigated in this paper. The material property gradient is based on the distribution of the power law in the direction of the plate thickness. The vibration equation is obtained depending on the classical plate theory (CPT), and resolved by the extension of the Differential quadrature approach (DQM). Furthermore, the mode shapes of the model are determined for simply supported moving graded plates with cracks. The present natural frequencies results are compared with those available in the published literature and a good agreement is found. The effect of key parameters such as plate velocity, crack length ratio, gradient index, and porosity on the dynamic characteristics of axial moving systems in addition to their physical interpretations is described [ABSTRACT FROM AUTHOR]

The Micro-Electro-Mechanical System (MEMS) based heat exchangers had become popular recently in many practical applications. For example, MEMS heat exchangers can be used as a cooling system for micro-chips squeezed into smaller and smaller spaces, with very little place for heat to escape. Therefore, the improvement of their heat transfer characteristics is a key issue for the development of micro-scale integrated systems. In this paper, it was implemented a basic unit model for a micro-heat exchanger using commercial Finite Element Method (FEM) package Comsol Multiphysics (version 5.0). Thermal performance for this model having four different fluid channel geometries: circular, rhombic, square and octagonal was investigated in terms of temperature gradient, total internal energy and total enthalpy distributions along the hot and cold channels. [ABSTRACT FROM AUTHOR]

Wave energy exploits the movement of the wind across the surface of the sea to provide an inexhaustible, carbon-free energy source for electricity generation. This can potentially provide a significant contribution to electricity generation supply in the UK, meeting up to 20% of the UK's electricity demand. This represents 30-50 MW capacity of electrical energy by 2020, and potentially 27 GW by 2050 as technology within the industry develops and matures. Studies show that developing marine energy resources in the UK can save 60 metric tons of carbon dioxide by 2025 and aid in the UK meeting 20-20-20 renewable energy objectives. In this paper the design of a wave power station integrated with a decommissioned offshore oil platform is proposed. This approach provides ideal conditions for the exploitation of wave energy for electricity generation. It not only saves the cost of decommissioning but also provides the offshore oil platform with new life, generating electrical energy from an inexhaustible source. The objective of this work was to conduct an extensive feasibility study to develop a proof of concept design for wave energy generation integrated with an offshore oil platform. [ABSTRACT FROM AUTHOR]

Photovoltaic modules operate under a large range of conditions. This, combined with the fact that manufacturers provide electrical parameters at specific conditions (STC, Standard Test Conditions) renders the prediction of a PV module's power efficiency very difficult. The most common model for calculating the electric characteristics and, consequently, the generated power of a photovoltaic unit under real transient conditions is the five-parameter model. It is noteworthy that this model demands a relatively small amount of data that are normally available from the manufacturer. The purpose of this paper is to determine the actual benefit in the power efficiency of a photovoltaic unit that has its cell temperature reduced using a phase change material. All approaches of the five-parameter model involve simulating the solar cell, photovoltaic module or photovoltaic array with an one-diode equivalent electrical circuit. The operation of such a circuit is defined by a characteristic I-V equation which contains five parameters: the photocurrent I0, the reverse saturation current Il, the series resistance Rs, the parallel resistance Rp and, depending on the approach, either the diode's ideality factor m or the modified ideality factor α. For every pair of cell temperature T and solar radiation G, a new characteristic I-V is in effect and, therefore, the above parameters must be calculated anew using correlations between reference and non-reference values of the parameters. [ABSTRACT FROM AUTHOR]