Search results for: Energy conversion technologies
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4051

Search results for: Energy conversion technologies

2641 Performance of Nine Different Types of PV Modules in the Tropical Region

Authors: Jiang Fan

Abstract:

With growth of PV market in tropical region, it is necessary to investigate the performance of different types of PV technology under the tropical weather conditions. Singapore Polytechnic was funded by Economic Development Board (EDB) to set up a solar PV test-bed for the research on performance of different types of PV modules in the country. The PV test-bed installed the nine different types of PV systems that are integrated to power utility grid for monitoring and analyzing their operating performances. This paper presents the 12 months operational data of nine different PV systems and analyses on performances of installed PV systems using energy yield and performance ratio. The nine types of PV systems under test have shown their energy yields ranging from 2.67 to 3.36 kWh/kWp and their performance ratios (PRs) ranging from 70% to 88%.

Keywords: Monocrystalline, Multicrystalline, Amorphous Silicon, Cadmium Telluride and thin film PV.

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2640 Computational Model for Predicting Effective siRNA Sequences Using Whole Stacking Energy (% G) for Gene Silencing

Authors: Reena Murali, David Peter S.

Abstract:

The small interfering RNA (siRNA) alters the regulatory role of mRNA during gene expression by translational inhibition. Recent studies show that upregulation of mRNA because serious diseases like cancer. So designing effective siRNA with good knockdown effects plays an important role in gene silencing. Various siRNA design tools had been developed earlier. In this work, we are trying to analyze the existing good scoring second generation siRNA predicting tools and to optimize the efficiency of siRNA prediction by designing a computational model using Artificial Neural Network and whole stacking energy (%G), which may help in gene silencing and drug design in cancer therapy. Our model is trained and tested against a large data set of siRNA sequences. Validation of our results is done by finding correlation coefficient of experimental versus observed inhibition efficacy of siRNA. We achieved a correlation coefficient of 0.727 in our previous computational model and we could improve the correlation coefficient up to 0.753 when the threshold of whole tacking energy is greater than or equal to -32.5 kcal/mol.

Keywords: Artificial Neural Network, Double Stranded RNA, RNA Interference, Short Interfering RNA.

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2639 An Energy Aware Dispatch Scheme WSNs

Authors: Siddhartha Chauhan, Kumar S. Pandey, Prateek Chandra

Abstract:

One of the key research issues in wireless sensor networks (WSNs) is how to efficiently deploy sensors to cover an area. In this paper, we present a Fishnet Based Dispatch Scheme (FiBDS) with energy aware mobility and interest based sensing angle. We propose two algorithms, one is FiBDS centralized algorithm and another is FiBDS distributed algorithm. The centralized algorithm is designed specifically for the non-time critical applications, commonly known as non real-time applications while the distributed algorithm is designed specifically for the time critical applications, commonly known as real-time applications. The proposed dispatch scheme works in a phase-selection manner. In this in each phase a specific constraint is dealt with according to the specified priority and then moved onto the next phase and at the end of each only the best suited nodes for the phase are chosen. Simulation results are presented to verify their effectiveness. 

Keywords: Dispatch Scheme, Energy Aware Mobility, Interest based Sensing, Wireless Sensor Networks (WSNs).

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2638 Coproduction of Fructose and Ethanol from Dates by S. cerevisiae ATCC 36859

Authors: M. A. Zeinelabdeen, A. E. Abasaeed, M. H. Gaily, A. K. Sulieman, M. D. Putra

Abstract:

Coproduction of fructose and ethanol from dates extract by a glucose-selective S. cerevisiae ATCC 36859 strain has been studied. Various initial sugar concentrations (i.e., 131.4, 315.3, 408.2, and 500.0 g/l) have been tested. The fermentation experiments were performed in a water shaker bath at 30°C and 120 rpm. The results showed that highest yields of fructose (95.0%) and ethanol (72.8%) were achieved for the 131.4 g/l concentration. Increasing the initial concentration to 315.3 g/l resulted in lower yields of fructose (82.2%) and ethanol (61.0%). However, further increase to 408.2 g/l increased the fructose yield (97.5%) at the expense of ethanol yield (42.0%) due to probable substrate inhibitions that resulted in lower glucose conversion. At 500 g initial sugar/l the growth rate of ATCC 36859 was highly inhibited. 

Keywords: Dates, ethanol, fructose, fermentation, S. cerevisiae.

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2637 Effect of Calcination Temperature and MgO Crystallite Size on MgO/TiO2 Catalyst System for Soybean Transesterification

Authors: Liberty L Mguni, Reinout Meijboom, Kalala Jalama

Abstract:

The effect of calcination temperature and MgO crystallite sizes on the structure and catalytic performance of TiO2 supported nano-MgO catalyst for the trans-esterification of soybean oil has been studied. The catalyst has been prepared by deposition precipitation method, characterised by XRD and FTIR and tested in an autoclave at 225oC. The soybean oil conversion after 15 minutes of the trans-esterification reaction increased when the calcination temperature was increased from 500 to 600oC and decreased with further increase in calcination temperature. Some glycerolysis activity was also detected on catalysts calcined at 600 and 700oC after 45 minutes of reaction. The trans-esterification reaction rate increased with the decrease in MgO crystallite size for the first 30 min.

Keywords: Calcination temperature, crystallite size, MgO/TiO2, transesterification

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2636 A Study on the Effectiveness of Alternative Commercial Ventilation Inlets That Improve Energy Efficiency of Building Ventilation Systems

Authors: Brian Considine, Aonghus McNabola, John Gallagher, Prashant Kumar

Abstract:

Passive air pollution control devices known as aspiration efficiency reducers (AER) have been developed using aspiration efficiency (AE) concepts. Their purpose is to reduce the concentration of particulate matter (PM) drawn into a building air handling unit (AHU) through alterations in the inlet design improving energy consumption. In this paper an examination is conducted into the effect of installing a deflector system around an AER-AHU inlet for both a forward and rear-facing orientations relative to the wind. The results of the study found that these deflectors are an effective passive control method for reducing AE at various ambient wind speeds over a range of microparticles of varying diameter. The deflector system was found to induce a large wake zone at low ambient wind speeds for a rear-facing AER-AHU, resulting in significantly lower AE in comparison to without. As the wind speed increased, both contained a wake zone but have much lower concentration gradients with the deflectors. For the forward-facing models, the deflector system at low ambient wind speed was preferred at higher Stokes numbers but there was negligible difference as the Stokes number decreased. Similarly, there was no significant difference at higher wind speeds across the Stokes number range tested. The results demonstrate that a deflector system is a viable passive control method for the reduction of ventilation energy consumption.

Keywords: Aspiration efficiency, energy, particulate matter, ventilation.

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2635 Determination of Myocardial Function Using Heart Accumulated Radiopharmaceuticals

Authors: C. C. D. Kulathilake, M. Jayatilake, T. Takahashi

Abstract:

The myocardium is composed of specialized muscle which relies mainly on fatty acid and sugar metabolism and it is widely contribute to the heart functioning. The changes of the cardiac energy-producing system during heart failure have been proved using autoradiography techniques. This study focused on evaluating sugar and fatty acid metabolism in myocardium as cardiac energy getting system using heart-accumulated radiopharmaceuticals. Two sets of autoradiographs of heart cross sections of Lewis male rats were analyzed and the time- accumulation curve obtained with use of the MATLAB image processing software to evaluate fatty acid and sugar metabolic functions.

Keywords: Autoradiographs, fatty acid, radiopharmaceuticals and sugar.

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2634 CO2 Abatement by Methanol Production from Flue-Gas in Methanol Plant

Authors: A. K. Sayah, Sh. Hosseinabadi, M. Farazar

Abstract:

This study investigates CO2 mitigation by methanol synthesis from flue gas CO2 and H2 generation through water electrolysis. Electrolytic hydrogen generation is viable provided that the required electrical power is supplied from renewable energy resources; whereby power generation from renewable resources is yet commercial challenging. This approach contribute to zero-emission, moreover it produce oxygen which could be used as feedstock for chemical process. At ZPC, however, oxygen would be utilized through partial oxidation of methane in autothermal reactor (ATR); this makes ease the difficulties of O2 delivery and marketing. On the other hand, onboard hydrogen storage and consumption; in methanol plant; make the project economically more competitive.

Keywords: Biomass, CO2 abatement, flue gas recovery, renewable energy, sustainable development.

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2633 Simulation Model for Optimizing Energy in Supply Chain Management

Authors: Nazli Akhlaghinia, Ali Rajabzadeh Ghatari

Abstract:

In today's world, with increasing environmental awareness, firms are facing severe pressure from various stakeholders, including the government and customers, to reduce their harmful effects on the environment. Over the past few decades, the increasing effects of global warming, climate change, waste, and air pollution have increased the global attention of experts to the issue of the green supply chain and led them to the optimal solution for greenery. Green supply chain management (GSCM) plays an important role in motivating the sustainability of the organization. With increasing environmental concerns, the main objective of the research is to use system thinking methodology and Vensim software for designing a dynamic system model for green supply chain and observing behaviors. Using this methodology, we look for the effects of a green supply chain structure on the behavioral dynamics of output variables. We try to simulate the complexity of GSCM in a period of 30 months and observe the complexity of behaviors of variables including sustainability, providing green products, and reducing energy consumption, and consequently reducing sample pollution.

Keywords: Supply chain management, green supply chain management, system dynamics, energy consumption.

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2632 Evaluation of Easy-to-Use Energy Building Design Tools for Solar Access Analysis in Urban Contexts: Comparison of Friendly Simulation Design Tools for Architectural Practice in the Early Design Stage

Authors: M. Iommi, G. Losco

Abstract:

Current building sector is focused on reduction of energy requirements, on renewable energy generation and on regeneration of existing urban areas. These targets need to be solved with a systemic approach, considering several aspects simultaneously such as climate conditions, lighting conditions, solar radiation, PV potential, etc. The solar access analysis is an already known method to analyze the solar potentials, but in current years, simulation tools have provided more effective opportunities to perform this type of analysis, in particular in the early design stage. Nowadays, the study of the solar access is related to the easiness of the use of simulation tools, in rapid and easy way, during the design process. This study presents a comparison of three simulation tools, from the point of view of the user, with the aim to highlight differences in the easy-to-use of these tools. Using a real urban context as case study, three tools; Ecotect, Townscope and Heliodon, are tested, performing models and simulations and examining the capabilities and output results of solar access analysis. The evaluation of the ease-to-use of these tools is based on some detected parameters and features, such as the types of simulation, requirements of input data, types of results, etc. As a result, a framework is provided in which features and capabilities of each tool are shown. This framework shows the differences among these tools about functions, features and capabilities. The aim of this study is to support users and to improve the integration of simulation tools for solar access with the design process.

Keywords: Solar access analysis, energy building design tools, urban planning, solar potential.

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2631 Energy Efficient Resource Allocation in Distributed Computing Systems

Authors: Samee Ullah Khan, C. Ardil

Abstract:

The problem of mapping tasks onto a computational grid with the aim to minimize the power consumption and the makespan subject to the constraints of deadlines and architectural requirements is considered in this paper. To solve this problem, we propose a solution from cooperative game theory based on the concept of Nash Bargaining Solution. The proposed game theoretical technique is compared against several traditional techniques. The experimental results show that when the deadline constraints are tight, the proposed technique achieves superior performance and reports competitive performance relative to the optimal solution.

Keywords: Energy efficient algorithms, resource allocation, resource management, cooperative game theory.

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2630 Resilient Manufacturing: Use of Augmented Reality to Advance Training and Operating Practices in Manual Assembly

Authors: L. C. Moreira, M. Kauffman

Abstract:

This paper outlines the results of an experimental research on deploying an emerging augmented reality (AR) system for real-time task assistance (or work instructions) of highly customised and high-risk manual operations. The focus is on human operators’ training effectiveness and performance and the aim is to test if such technologies can support enhancing the knowledge retention levels and accuracy of task execution to improve health and safety (H&S). An AR enhanced assembly method is proposed and experimentally tested using a real industrial process as case study for electric vehicles’ (EV) battery module assembly. The experimental results revealed that the proposed method improved the training practices and performance through increases in the knowledge retention levels from 40% to 84%, and accuracy of task execution from 20% to 71%, when compared to the traditional paper-based method. The results of this research validate and demonstrate how emerging technologies are advancing the choice for manual, hybrid or fully automated processes by promoting the XR-assisted processes, and the connected worker (a vision for Industry 4 and 5.0), and supporting manufacturing become more resilient in times of constant market changes.

Keywords: Augmented reality, extended reality, connected worker, XR-assisted operator, manual assembly 4.0, industry 5.0, smart training, battery assembly.

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2629 High School Stem Curriculum and Example of Laboratory Work That Shows How Microcomputers Can Help in Understanding of Physical Concepts

Authors: Jelena Slugan, Ivica Ružić

Abstract:

We are witnessing the rapid development of technologies that change the world around us. However, curriculums and teaching processes are often slow to adapt to the change; it takes time, money and expertise to implement technology in the classroom. Therefore, the University of Split, Croatia, partnered with local school Marko Marulić High School and created the project "Modern competence in modern high schools" as part of which five different curriculums for STEM areas were developed. One of the curriculums involves combining information technology with physics. The main idea was to teach students how to use different circuits and microcomputers to explore nature and physical phenomena. As a result, using electrical circuits, students are able to recreate in the classroom the phenomena that they observe every day in their environment. So far, high school students had very little opportunity to perform experiments independently, and especially, those physics experiment did not involve ICT. Therefore, this project has a great importance, because the students will finally get a chance to develop themselves in accordance to modern technologies. This paper presents some new methods of teaching physics that will help students to develop experimental skills through the study of deterministic nature of physical laws. Students will learn how to formulate hypotheses, model physical problems using the electronic circuits and evaluate their results. While doing that, they will also acquire useful problem solving skills.

Keywords: ICT in physics, curriculum, laboratory activities, STEM.

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2628 Analyzing the Performance Properties of Stress Absorbing Membrane Interlayer Modified with Recycled Crumb Rubber

Authors: Seyed Mohammad Asgharzadeh, Moein Biglari

Abstract:

Asphalt overlay is the most commonly used technique of pavement rehabilitation. However, the reflective cracks which occur on the overlay surface after a short period of time are the most important distresses threatening the durability of new overlays. Stress Absorbing Membrane Interlayers (SAMIs) are used to postpone the reflective cracking in the overlays. Sand asphalt mixtures, in unmodified or crumb rubber modified (CRM) conditions, can be used as an SAMI material. In this research, the performance properties of different SAMI applications were evaluated in the laboratory using an Indirect Tensile (IDT) fracture energy. The IDT fracture energy of sand asphalt samples was also evaluated and then compared to that of the regular dense graded asphalt used as an overlay. Texas boiling water and modified Lottman tests were also conducted to evaluate the moisture susceptibility of sand asphalt mixtures. The test results showed that sand asphalt mixtures can stand higher levels of energy before cracking, and this is even more pronounced for the CRM sand mix. Sand asphalt mixture using CRM binder was also shown to be more resistance to moisture induced distresses.

Keywords: SAMI, sand asphalt, crumb rubber, Lottman Modified Test.

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2627 Development of Cooling Load Demand Program for Building in Malaysia

Authors: Zamri Noranai, Dayang Siti Zainab Abang Bujang, Rosli Asmawi, Hamidon Salleh, Mohammad Zainal Md Yusof

Abstract:

Air conditioning is mainly to be used as human comfort medium. It has been use more often in country in which the daily temperatures are high. In scientific, air conditioning is defined as a process of controlling the moisture, cooling, heating and cleaning air. Without proper estimation of cooling load, big amount of waste energy been used because of unsuitable of air conditioning system are not considering to overcoming heat gains from surrounding. This is due to the size of the room is too big and the air conditioning has to use more energy to cool the room and the air conditioning is too small for the room. The studies are basically to develop a program to calculate cooling load. Through this study it is easy to calculate cooling load estimation. Furthermore it-s help to compare the cooling load estimation by hourly and yearly. Base on the last study that been done, the developed software are not user-friendly. For individual without proper knowledge of calculating cooling load estimation might be problem. Easy excess and user-friendly should be the main objective to design something. This program will allow cooling load able be estimate by any users rather than estimation by using rule of thumb. Several of limitation of case study is judged to sure it-s meeting to Malaysia building specification. Finally validation is done by comparison manual calculation and by developed program.

Keywords: Building, Energy and Coaling Load

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2626 Advanced Energy Absorbers Used in Blast Resistant Systems

Authors: Martina Drdlová, Michal Frank, Radek Řídký, Jaroslav Buchar, Josef Krátký

Abstract:

The main aim of the presented experiments is to improve behaviour of sandwich structures under dynamic loading, such as crash or explosion. This paper describes experimental investigation on the response of new advanced materials to low and high velocity load. Blast wave energy absorbers were designed using two types of porous lightweight raw particle materials based on expanded glass and ceramics with dimensions of 0.5-1 mm, combined with polymeric binder. The effect of binder amount on the static and dynamic properties of designed materials was observed. Prism shaped specimens were prepared and loaded to obtain physicomechanical parameters – bulk density, compressive and flexural strength under quasistatic load, the dynamic response was determined using Split Hopkinson Pressure bar apparatus. Numerical investigation of the material behaviour in sandwich structure was performed using implicit/explicit solver LS-Dyna. As the last step, the developed material was used as the interlayer of blast resistant litter bin, and it´s functionality was verified by real field blast tests.

Keywords: Blast energy absorber, SHPB, expanded glass, expanded ceramics.

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2625 Deformation Mechanisms at Elevated Temperatures: Influence of Momenta and Energy in the Single Impact Test

Authors: Harald Rojacz, Markus Varga, Horst Winkelmann

Abstract:

Within this work High Temperature Single Impact Studies were performed to evaluate deformation mechanisms at different energy and momentum levels. To show the influence of different microstructures and hardness levels and their response to single impacts four different materials were tested at various temperatures up to 700°C. One carbide reinforced NiCrBSi based Metal Matrix Composite and three different steels were tested. The aim of this work is to determine critical energies for fracture appearance and the materials response at different energy and momenta levels. Critical impact loadings were examined at elevated temperatures to limit operating conditions in impact dominated regimes at elevated temperatures. The investigations on the mechanisms were performed using different means of microscopy at the surface and in metallographic cross sections. Results indicate temperature dependence of the occurrence of cracks in hardphase rich materials, such as Metal Matrix Composites High Speed Steels and the influence of different impact momenta at constant energies on the deformation of different steels.

Keywords: Deformation, High Temperature, Metal Matrix Composite, Single Impact Test, Steel.

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2624 3 State Current Mode of a Grid Connected PV Converter

Authors: Attila Balogh, Eszter Varga, István Varjasi

Abstract:

Nowadays in applications of renewable energy sources it is important to develop powerful and energy-saving photovoltaic converters and to keep the prescriptions of the standards. In grid connected PV converters the obvious solution to increase the efficiency is to reduce the switching losses. Our new developed control method reduces the switching losses and keeps the limitations of the harmonic distortion standards. The base idea of the method is the utilization of 3-state control causing discontinuous current mode at low input power. In the following sections the control theory, the realizations and the simulation results are presented.

Keywords: Discontinuous current, high efficiency, PVconverter, control method.

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2623 Thermodynamic Analysis of Ventilated Façades under Operating Conditions in Southern Spain

Authors: Carlos A. D. Torres, Antonio D. Delgado

Abstract:

In this work we study the thermodynamic behavior of some ventilated facades under summer operating conditions in Southern Spain. Under these climatic conditions, indoor comfort implies a high energetic demand due to high temperatures that usually are reached in this season in the considered geographical area.

The aim of this work is to determine if during summer operating conditions in Southern Spain, ventilated façades provide some energy saving compared to the non-ventilated façades and to deduce their behavior patterns in terms of energy efficiency.

The modelization of the air flow in the channel has been performed by using Navier-Stokes equations for thermodynamic flows. Numerical simulations have been carried out with a 2D Finite Element approach.

This way, we analyze the behavior of ventilated façades under different weather conditions as variable wind, variable temperature and different levels of solar irradiation.

CFD computations show the combined effect of the shading of the external wall and the ventilation by the natural convection into the air gap achieve a reduction of the heat load during the summer period. This reduction has been evaluated by comparing the thermodynamic performances of two ventilated and two unventilated façades with the same geometry and thermophysical characteristics.

Keywords: Passive cooling, ventilated façades, energy-efficient building, CFD, FEM.

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2622 Experimental Investigation of the Effect of Hydrogen Manifold Injection on the Performance of Compression Ignition Engines

Authors: Haroun A.K. Shahad, Nabeel Abdul-Hadi

Abstract:

Experiments were carried out to evaluate the influence of the addition of hydrogen to the inlet air on the performance of a single cylinder direct injection diesel engine. Hydrogen was injected in the inlet manifold. The addition of hydrogen was done on energy replacement basis. It was found that the addition of hydrogen improves the combustion process due to superior combustion characteristics of hydrogen in comparison to conventional diesel fuels. It was also found that 10% energy replacement improves the engine thermal efficiency by about 40% and reduces the sfc by about 35% however the volumetric efficiency was reduced by about 35%.

Keywords: Hydrogen, Blended fuel, Manifold injection , Performance , Combustion

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2621 Graphical Approach for Targeting Work Exchange Networks

Authors: Hui Chen, Xiao Feng

Abstract:

Depressurization and pressurization streams in industrial systems constitute a work exchange network (WEN). In this paper, a novel graphical approach for targeting energy conservation potential of a WEN is proposed. Through constructing the composite work curves in the pressure-work diagram and assuming all of the mechanical energy of the depressurization streams is recovered by expanders, the maximum work target of a WEN can be determined via the proposed targeting steps. A WEN in an ammonia production process is used as a case study to illustrate the applicability of the proposed graphical approach.

Keywords: Expanders, Graphical approach, Pressure-work diagram, Work exchange network, Work target

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2620 A Novel Digital Calibration Technique for Gain and Offset Mismatch in TIΣΔ ADCs

Authors: Ali Beydoun, Van-Tam Nguyen, Patrick Loumeau

Abstract:

Time interleaved sigma-delta (TIΣΔ) architecture is a potential candidate for high bandwidth analog to digital converters (ADC) which remains a bottleneck for software and cognitive radio receivers. However, the performance of the TIΣΔ architecture is limited by the unavoidable gain and offset mismatches resulting from the manufacturing process. This paper presents a novel digital calibration method to compensate the gain and offset mismatch effect. The proposed method takes advantage of the reconstruction digital signal processing on each channel and requires only few logic components for implementation. The run time calibration is estimated to 10 and 15 clock cycles for offset cancellation and gain mismatch calibration respectively.

Keywords: sigma-delta, calibration, gain and offset mismatches, analog-to-digital conversion, time-interleaving.

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2619 The Solar Wall in the Italian Climates

Authors: F. Stazi, C. Di Perna, C. Filiaci, A. Stazi

Abstract:

Passive systems were born with the purpose of the greatest exploitation of solar energy in cold climates and high altitudes. They spread themselves until the 80-s all over the world without any attention to the specific climate and the summer behavior; this caused the deactivation of the systems due to a series of problems connected to the summer overheating, the complex management and the rising of the dust. Until today the European regulation limits only the winter consumptions without any attention to the summer behavior but, the recent European EN 15251 underlines the relevance of the indoor comfort, and the necessity of the analytic studies validation by monitoring case studies. In the porpose paper we demonstrate that the solar wall is an efficient system both from thermal comfort and energy saving point of view and it is the most suitable for our temperate climates because it can be used as a passive cooling sistem too. In particular the paper present an experimental and numerical analisys carried out on a case study with nine different solar passive systems in Ancona, Italy. We carried out a detailed study of the lodging provided by the solar wall by the monitoring and the evaluation of the indoor conditions. Analyzing the monitored data, on the base of recognized models of comfort (ISO, ASHRAE, Givoni-s BBCC), is emerged that the solar wall has an optimal behavior in the middle seasons. In winter phase this passive system gives more advantages in terms of energy consumptions than the other systems, because it gives greater heat gain and therefore smaller consumptions. In summer, when outside air temperature return in the mean seasonal value, the indoor comfort is optimal thanks to an efficient transversal ventilation activated from the same wall.

Keywords: Building envelope, energy saving, passive solarwall, thermal comfort.

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2618 Theoretical Review on Influencing Factors in the Design of Parabolic Trough Collector

Authors: S. N. Vijayan, S. Sendhil Kumar

Abstract:

Recent years have an upward trend in the research of renewable energy sector, due to the low availability of resources and huge consumption of conventional energies. Considerable renewable energy can be achieved from the available solar power with the utilization of collecting systems. Parabolic trough concentrating collector systems are mostly used to utilize maximum availability of solar power. This paper reviews the contributing factors for the overall performance of parabolic trough collectors. Its performance depends on the operating parameters such as the type of receiver and the collector material, medium of heat transfer, type of application and various climatic conditions.

Keywords: Solar radiation, parabolic trough collector, thermal analysis, efficiency.

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2617 Development of Better Quality Low-Cost Activated Carbon from South African Pine Tree (Pinus patula) Sawdust: Characterization and Comparative Phenol Adsorption

Authors: L. Mukosha, M. S. Onyango, A. Ochieng, H. Kasaini

Abstract:

The remediation of water resources pollution in developing countries requires the application of alternative sustainable cheaper and efficient end-of-pipe wastewater treatment technologies. The feasibility of use of South African cheap and abundant pine tree (Pinus patula) sawdust for development of lowcost AC of comparable quality to expensive commercial ACs in the abatement of water pollution was investigated. AC was developed at optimized two-stage N2-superheated steam activation conditions in a fixed bed reactor, and characterized for proximate and ultimate properties, N2-BET surface area, pore size distribution, SEM, pHPZC and FTIR. The sawdust pyrolysis activation energy was evaluated by TGA. Results indicated that the chars prepared at 800oC and 2hrs were suitable for development of better quality AC at 800oC and 47% burn-off having BET surface area (1086m2/g), micropore volume (0.26cm3/g), and mesopore volume (0.43cm3/g) comparable to expensive commercial ACs, and suitable for water contaminants removal. The developed AC showed basic surface functionality at pHPZC at 10.3, and a phenol adsorption capacity that was higher than that of commercial Norit (RO 0.8) AC. Thus, it is feasible to develop better quality low-cost AC from (Pinus patula) sawdust using twostage N2-steam activation in fixed-bed reactor.

Keywords: Activated carbon, phenol adsorption, sawdust integrated utilization, economical wastewater treatment.

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2616 A Comparative Analysis of Solid Waste Treatment Technologies on Cost and Environmental Basis

Authors: Nesli Aydin

Abstract:

Waste management decision making in developing countries has moved towards being more pragmatic, transparent, sustainable and comprehensive. Turkey is required to make its waste related legislation compatible with European Legislation as it is a candidate country of the European Union. Improper Turkish practices such as open burning and open dumping practices must be abandoned urgently, and robust waste management systems have to be structured. The determination of an optimum waste management system in any region requires a comprehensive analysis in which many criteria are taken into account by stakeholders. In conducting this sort of analysis, there are two main criteria which are evaluated by waste management analysts; economic viability and environmentally friendliness. From an analytical point of view, a central characteristic of sustainable development is an economic-ecological integration. It is predicted that building a robust waste management system will need significant effort and cooperation between the stakeholders in developing countries such as Turkey. In this regard, this study aims to provide data regarding the cost and environmental burdens of waste treatment technologies such as an incinerator, an autoclave (with different capacities), a hydroclave and a microwave coupled with updated information on calculation methods, and a framework for comparing any proposed scenario performances on a cost and environmental basis.

Keywords: Decision making, economic viability, environmentally friendliness, stakeholder, waste management systems.

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2615 Factors in a Sustainability Assessment of New Types of Closed Cavity Façades

Authors: Zoran Veršić, Josip Galić, Marin Binički, Lucija Stepinac

Abstract:

With the current increase in CO2 emissions and global warming, the sustainability of both existing and new solutions must be assessed on a wide scale. As the implementation of closed cavity façades (CCF) is on the rise, various factors must be included in the analysis of new types of CCF. This paper aims to cover the relevant factors included in the sustainability assessment of new types of CCF. Several mathematical models are being used to describe the physical behavior of CCF. Depending on the type of CCF, they cover the main factors which affect the durability of the façade: thermal behavior of various elements in the façade, stress and deflection of the glass panels, pressure and the moisture control in the cavity. CCF itself represents a complex system in which all mentioned factors must be considered mutually. Still, the façade is only an envelope of a more complex system, the building. Choice of the façade dictates the heat loss and the heat gain, thermal comfort of inner space, natural lighting, and ventilation. Annual energy consumption for heating, cooling, lighting, and maintenance costs will present the operational advantages or disadvantages of the chosen façade system in economic and environmental aspects. Still, the only operational viewpoint is not all-inclusive. As the building codes constantly demand higher energy efficiency as well as transfer to renewable energy sources, the ratio of embodied and lifetime operational energy footprint of buildings is changing. With the drop in operational energy CO2 emissions, embodied energy emissions present a larger and larger share in the lifecycle emissions of the building. Taking all into account, the sustainability assessment of a façade, as well as other major building elements, should include all mentioned factors during the lifecycle of an element. The challenge of such an approach is a timescale. Depending on the climatic conditions on the building site, the expected lifetime of a glazed façade can exceed 25 years. In such a timespan, some of the factors can be estimated more precisely than the others. However, the ones depending on the socio-economic conditions are more likely to be harder to predict than the natural ones like the climatic load. This work recognizes and summarizes the relevant factors needed for the assessment of a new type of CCF, considering the entire lifetime of a façade element in an environmental aspect.

Keywords: Assessment, closed cavity façade, life cycle, sustainability.

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2614 Management of Meskit (Prosopis juliflora) Tree in Oman: The Case of Using Meskit (Prosopis juliflora) Pods for Feeding Omani Sheep

Authors: S. Al-Khalasi, O. Mahgoub, H. Yaakub

Abstract:

This study evaluated the use of raw or processed Prosopis juliflora (Meskit) pods as a major ingredient in a formulated ration to provide an alternative non-conventional concentrate for livestock feeding in Oman. Dry Meskit pods were reduced to lengths of 0.5- 1.0 cm to ensure thorough mixing into three diets. Meskit pods were subjected to two types of treatments; roasting and soaking. They were roasted at 150оC for 30 minutes using a locally-made roasting device (40 kg barrel container rotated by electric motor and heated by flame gas cooker). Chopped pods were soaked in tap water for 24 hours and dried for 2 days under the sun with frequent turning. The Meskit-pod-based diets (MPBD) were formulated and pelleted from 500 g/kg ground Meskit pods, 240 g/kg wheat bran, 200 g/kg barley grain, 50 g/kg local dried sardines and 10 g/kg of salt. Twenty four 10 months-old intact Omani male lambs with average body weight of 27.3 kg (± 0.5 kg) were used in a feeding trial for 84 days. They were divided (on body weight basis) and allocated to four diet combination groups. These were: Rhodes grass hay (RGH) plus a general ruminant concentrate (GRC); RGH plus raw Meskit pods (RMP) based concentrate; RGH plus roasted Meskit pods (ROMP) based concentrate; RGH plus soaked Meskit pods (SMP) based concentrate Daily feed intakes and bi-weekly body weights were recorded. MPBD had higher contents of crude protein (CP), acid detergent fibre (ADF) and neutral detergent fibre (NDF) than the GRC. Animals fed various types of MPBD did not show signs of ill health. There was a significant effect of feeding ROMP on the performance of Omani sheep compared to RMP and SMP. The ROMP fed animals had similar performance to those fed the GRC in terms of feed intake, body weight gain and feed conversion ratio (FCR).This study indicated that roasted Meskit pods based diet may be used instead of the commercial concentrate for feeding Omani sheep without adverse effects on performance. It offers a cheap alternative source of protein and energy for feeding Omani sheep. Also, it might help in solving the spread impact of Meskit trees, maintain the ecosystem and helping in preserving the local tree species.

Keywords: Growth, Meskit, Omani sheep, Prosopis juliflora.

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2613 The Analysis of Internet and Social Media Behaviors of the Students in the Higher School of Vocational and Technical Sciences

Authors: Mehmet Balci, Sakir Tasdemir, Mustafa Altin, Ozlem Bozok

Abstract:

Our globalizing world has become almost a small village and everyone can access any information at any time. Everyone lets each other know who does whatever in which place. We can learn which social events occur in which place in the world. From the perspective of education, the course notes that a lecturer use in lessons in a university in any state of America can be examined by a student studying in a city of Africa or the Far East. This dizzying communication we have mentioned happened thanks to fast developments in computer and internet technologies. While these developments occur in the world, Turkey that has a very large young population and whose electronic infrastructure rapidly improves has also been affected by these developments. Nowadays, mobile devices have become common and thus, it causes to increase data traffic in social networks. This study was carried out on students in the different age groups in Selcuk University Vocational School of Technical Sciences, the Department of Computer Technology. Students’ opinions about the use of internet and social media were obtained. The features such as using the Internet and social media skills, purposes, operating frequency, accessing facilities and tools, social life and effects on vocational education and so forth were explored. The positive effects and negative effects of both internet and social media use on the students in this department and findings are evaluated from different perspectives and results are obtained. In addition, relations and differences were found out statistically.

Keywords: Computer technologies, internet use, social network, higher vocational school.

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2612 Investigating Daylight Quality in Malaysian Government Office Buildings Through Daylight Factor and Surface Luminance

Authors: Mohd Zin Kandar, Mohd Sabere Sulaiman, Yong Razidah Rashid, Dilshan Remaz Ossen, Aminatuzuhariah MAbdullah, Lim Yaik Wah, Mansour Nikpour

Abstract:

In recent years, there has been an increasing interest in using daylight to save energy in buildings. In tropical regions, daylighting is always an energy saver. On the other hand, daylight provides visual comfort. According to standards, it shows that many criteria should be taken into consideration in order to have daylight utilization and visual comfort. The current standard in Malaysia, MS 1525 does not provide sufficient guideline. Hence, more research is needed on daylight performance. If architects do not consider daylight design, it not only causes inconvenience in working spaces but also causes more energy consumption as well as environmental pollution. This research had surveyed daylight performance in 5 selected office buildings from different area of Malaysian through experimental method. Several parameters of daylight quality such as daylight factor, surface luminance and surface luminance ratio were measured in different rooms in each building. The result of this research demonstrated that most of the buildings were not designed for daylight utilization. Therefore, it is very important that architects follow the daylight design recommendation to reduce consumption of electric power for artificial lighting while the sufficient quality of daylight is available.

Keywords: Daylight factor, Field measurement, Daylighting quality, Tropical

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