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Abstract: There is a large value in making Pulp and Paper mills more energy efficient. ABB has developed an energy assessment service where opportunities to save energy in the paper machine are identified. The energy assessment is done by quantifying energy flows, benchmarking energy users, data mining and steam sensitivity analysis and by experiments and additional measurements at the paper machine. Energy quantification helped in identifying main energy consumer, benchmarking was useful to assess the gap between operating performance and best performance whereas data mining and steam sensitivity analysis helped in studying the impact of key operating variables on performance of paper machines. After the assessment an action plan was presented to the mill for energy efficiency improvement together with a return on investment. [Copyright &y& Elsevier]

Abstract: The market for small Solar CombiSystems (SCSs) is penalized by its lack of common performance test method. The methodology proposed in this paper is based on the SCSPT procedure which tests each combisystem as a whole system on a semi-virtual test bench. Test results are used to identify a “Gray Box” model of the tested SCS, which includes an Artificial Neural Network. This model can then simulate the behavior of the system for any climate and any building. Results of all those simulations are finally used according to the FSC procedure in order to characterize the tested SCS performances with a simple curve. An experimental study of this methodology with two real SCS is presented in this paper. [Copyright &y& Elsevier]

Abstract: This paper presents an approach to measure, characterize and simulate photometric performances of light transmission efficiency of an innovative transparent concrete panel for façades. The transparency was obtained by a texture of PMMA resin insertions in the fiber reinforced concrete panel. In the first part of the paper integrating sphere measurements were collected to derive spectral optical properties of the panel. The optical properties of a specimen were measured for incidence angles between normal and 60° and the spectral results were reported. The data collected during the measures were used to: create and validate a simplified Radiance model of the panel and to optimize simulation parameters to estimate properly the total internal reflections effects thought the PMMA resin insertions. [Copyright &y& Elsevier]

Abstract: Urban neighborhoods could represent an optimal scale for the implementation of innovative energy strategies. However, barriers at the economic, regulatory and administrative level are still present. In this framework, it is important to operate on three levels of the energy system: by reducing energy demand; by optimizing generation and management system, and by integrating local renewable energy sources. In recent years, as a result of an important agreement with the Italian Ministry of Environment, Lombardy Region has supported numerous measures for energy efficiency and renewable resources integration among its territory. The funding supported different actions such as improvements of the buildings envelope, substitution of old gas boilers for heat generation with more efficient components, integration of solar thermal systems in buildings, hydrogen and more sustainable mobility, and district heating plants, which present contribution concerns. About district heating the incentives were provided within two different calls: one aimed at the creation of plants and district heating networks and another for the extension of existing systems. Main aim of the research is to evaluate effects, effectiveness, pros and cons of the several calls for funding; to that end a methodology was developed in order to collect the data and elaborate representative energy, environmental and economic indicators. The most important characteristics, conditions and technical features of the considered plants are described in the present paper trying to provide information on the effectiveness of the supporting measures taken in order to orient future choices and to identify the most promising strategies and technologies for improving energy and environmental performances of communities. In particular present paper is related to 10 district heating plants: 6 are based on biomass and located in mountain areas, 3 are based on natural gas and located in urban areas, while the last is connected to the urban waste to energy plant. One of the important lesson is learned is that district heating (fuelled by biomass, fossil, waste and CHP or not) represents an innovative field of knowledge far from standard: in general each plant has to be evaluated on the basis of specify characteristics and it is very hard to find out average performances from the environmental and economic point of view. The results obtained during the monitoring campaign could help in providing information on the effectiveness of the supporting measures adopted and also to orient future choices by Lombardy Region and, in particular, to identify the most promising technologies for improving energy and environmental performances of communities and to develop a model for the optimization of energy use in the built environment. [Copyright &y& Elsevier]

Abstract: This paper presents practical performance study of one axis mechanical tracking of PV grid connected system, which is designed, studied, and analyzed comparing with a fixed PV system at HIAST with capacity of 100 watts with tilt angle 35 degrees. This paper presents and compares the capital costs of tracking and fixed systems and the energy injected into the grid. [Copyright &y& Elsevier]

Abstract: In this paper, the ways of employing energy storage devices in hybrid powered orthoses have been discussed. Since these devices have many unrivalled advantages, they are environmentally safe, they store kinetic energy as potential energy and release it when it is needed and they do not need external power supply. In this paper an energy storage device (linear extension spring) has been implemented in FES-cycling, the efficiency has been calculated for different spring positions and different spring constants. It was clear that FES-cycling efficiency increases when the spring constant increases, then the pedal, spring and the overall powers were calculated, and it appears that by leaning the spring position the overall power will be always positive, and the spring absorbs the exceeded pedal energy and releases it when the pedal power is negative. This study highlights the importance of using energy storage devices to improve FES-cycling performance, which has been proven that such improvement is highly related to the mechanical design of the bicycle. [Copyright &y& Elsevier]

Abstract: A detailed mathematical simulation and experimental investigation of airflow in solar chimneys is studied in this paper. Several experimental studies were carried out on the solar chimney; their choice depends on the parameter of the design and the thermal performances for different geometrical configurations. The experimental tests show that the field speeds in the chimney is influenced by the width of the channel and also of the angle of inclination of the chimney. Therefore, investigations have been carried out in this paper to find the effect of inclination on the performance of solar chimney in Ouargla Province, Algeria. The simulation of this problem is implemented into the commercial CFD code Fluent 6.3. 26. The conservation equations of mass, continuity and energy are solved by the Finite Volume Method. The validation of the results is presented. An good agreement between the experimental results and simulation ones is observed. [Copyright &y& Elsevier]

Abstract: The need for air-conditioning in the Mediterranean countries is higher and higher due to the effects of global warming. This paper deals with an investigation of a high performance, solar-driven air-conditioning system, the project entitled “Mediterranean AIRCOND”, is funded by the European Community under the „Community Activities in the Field of the specific program for RTD and demonstration on “Energy, Environment and Sustainable Development”. “AIRCOND” aims to study and investigate performances of advanced solar driven air conditioning system; the field system is composed of three sub systems: the heating loop, the ejector cycle and the cold storage-air handling units: The heating loop is composed of a solar array of 60 square meters evacuated tube solar collectors; installed at a tilt angle of 45o and facing to south, a 3000 L tank which is used as hot water storage in order to cover the required energy by the ejector cycle. The cold water produced by the ejector cycle will be then transferred in a 900L cold storage tank filled with 800L micro-encapsulated phase change material (MEPCM) for cold storage. It is designed to meet the dynamic cooling load. The ejector was tested at the School of the Built Environment in the University of Nottingham in UK and then transferred to Tunisia for field evaluation. Many previous theory studies have been fulfilled on this technology but never been performed experimentally at this level. This paper presents the research effort made and the experience gained during the implementation of the whole system: Different operation strategies were followed during more than one year to make the ejector cycle functional. The whole procedure has turned out to be very difficult; it was particularly difficult to obtain a deep vacuum and to ensure a good vacuum quality; this is a necessary working condition for the ejector cycle. Successful ejector tests were obtained during 8min, 15min and 40min, after many investigations; later experiments led to 3hours of continuous working. Results are very promising; the installation is still under tests in order to obtain a whole day permanent working of the ejector cycle and so of all the solar installation. [Copyright &y& Elsevier]

Abstract: This paper analysis the cushion performance of the bucket unit for molded pulp material model, which based on the ANSYS software to simulate the compression test and study the effect variety of the draft angle and the height on the model. [Copyright &y& Elsevier]

Abstract: Power is the most important, the most widely used and the most convenient energy in modern society. However, grid system and the scale of construction and operation efficiency research are less coordination. This paper is mainly based on the grid, through the research of grid input-output characteristic, based on which establishing a more objective evaluation system from the economic angle and using the data envelopment analysis to evaluate their relative effectiveness. Finally, through the analysis for grid construction, this paper provides a set of scientific assessment method for the grid construction according to different state. [Copyright &y& Elsevier]

Abstract: Heterojunction silicon wafer solar cells, using a microcrystalline silicon (μc-Si:H) thin-film emitter and a very thin intrinsic amorphous silicon (a-Si:H) passivation layer between the crystalline silicon wafer and the emitter layer, have been reported to exhibit stable performance and high efficiency. Desired properties for the emitter layer include wide bandgap, low surface and interface recombination, and good doping efficiency. In this study, we report on the thin-film properties of p-doped μc-Si:H emitter layers deposited using RF (13.56MHz) PECVD, at different SiH4/H2 gas flow ratios, pressures, and temperatures at the same RF power. Trends relating deposition conditions to relevant film characteristics such as thickness, crystalline fraction and conductivity are discussed. Finally, device relevant symmetrical p+/i/c-Si/i/p+ heterojunction lifetime test structures are investigated, using the optimised parameters for p-doped μc-Si:H layers (discussed in this paper) and for intrinsic a-Si:H layers (discussed in a companion paper ). These exhibit promising effective lifetimes of up to 2.4ms at an injection level of 1015cm-3. [Copyright &y& Elsevier]

Abstract: This paper shows the topology of grid-connected green power system and the performances of the front-end threephase power inverter by applying an advanced state feedback control. The proposed topology benefits a common DCAC inverter which injects the generated power into the grid. The control structure of the power inverter is of vector control type, in synchronous reference frame, and it uses the power balance concept. The solution presented in this paper adds supplementary benefits to the power system beside to the conventional state feedback control: the designed input filter assures zero steady state error and an adequate component is added for dynamic rejection of the load disturbance. The obtained experimental results are shown. [Copyright &y& Elsevier]

Abstract: A new design of decentralized load-frequency controller for interconnected power systems with ac-dc parallel using Particle Swarm Optimization (PSO) algorithm is proposed in this paper. A HVDC link is connected in parallel with an existing ac tie-line to stabilize the frequency oscillations of the ac system. Any optimum controller selected for load frequency control of interconnected power systems should not only stabilize the power system but also reduce the system frequency and tie line power oscillations and settling time of the output responses. In practice Load Frequency Control (LFC) systems use simple Proportional Integral (PI) or Integral (I) controller parameters are usually tuned based on classical or trial-and-error approaches, they are incapable of obtaining good dynamic performance for various load change scenarios in multi-area power system. For this reason, in this paper the PI and I control parameters are tuned based on PSO algorithm method for the LFC control in the two-area power system. A two area interconnected thermal power system is considered to demonstrate the validity of the proposed controller. The simulation results show that the proposed controller provides better dynamic responses with minimal frequency and tie-line power deviations, quick settling time and guarantees closed-loop stability margin. [Copyright &y& Elsevier]

Abstract: This paper presents a method of calculating an advance angle in order to increase the torque-to-current ratio of a brushless DC (BLDC) motor. The BLDC motor is widely used in various industrial fields because of its high energy density and low maintenance. Because the BLDC motor drives with a square-wave current of electrical 120 degrees duration, the phase current must be commuted every 60 electrical degrees of rotation. Owing to the inductance levels of the motor winding process, the commutation induces a phase lag and deviations from the ideal square-wave current form. These non-ideal characteristics reduce the torque-to-current ratio. Advancing the commutation timing can improve the torque-to-current ratio. This paper analyzes the torque performances of the BLDC motor and proposes a method of calculating the advance angle in order to improve the torque-to-current ratio. The simulation results of a 20W, 20,000rpm BLDC motor verify the effectiveness of the proposed calculation method. [Copyright &y& Elsevier]

Abstract: Prefect fore-separation technology is the precondition and key to realize garbage synthesis treatment and increase resource utilization ratio. To the lower purity quotient and efficiency of plastic and paper separation, main factors influencing performance of horizontal flow separation are analyzed in detail, and reasonable processing and design parameter are studyed in this paper. Horizontal flow separator of urban garbage that structure is reasonable and parameter can be adjusted is designed. Technology reference and support is provided to production of urban garbage treatment factory. [Copyright &y& Elsevier]

Abstract: Robot is widely used in industrial domain and pose accuracy of end-effector is an important indicator for judging robot performance. Calibration is a necessary for operating industrial robot and an effective and efficient means of accuracy improvement. This paper describes the development of a calibration procedure for a five degree of freedom serial robot using the laser tracker. The main goal of this paper is to utilize measurements relative to the end-effector of the robot to compensate errors. The robot kinematic model is computed to help identify the deviations. Robot parameter deviations can be identified so that the nominal parameters can be corrected. The experimental results are validated effectively. [Copyright &y& Elsevier]

Abstract: The higher power microwave heating source, in the industrial and engineering needs, is obtained through inputting microwave energy of multi-open feed into cavity via near-field radiation, resulting in the coupling of each feed. Meanwhile, the initial situation, the ratio of fluid and the permittivity are highly nonlinear in the process of microwave heating during technical operation process by microwave heating process cycling fluid medium. This paper is presented an improved Anti-predatory Particle Swarm Optimization (APSO) algorithm to optimize the three parameters of PID controller, and is applied to control the complicated and coupling of microwave heating. It is shown through intelligent calculation and simulation experiments that the improved APSO has good performance. And this paper provides an alternative for control of multi-couple and uncertain objects in industry. [Copyright &y& Elsevier]

Abstract: Enterprises are pushed into a global competition based on internet with the boom of information technology, and e-Business has been the main platform of businesses. Efficient and effective e-business system has been one of the key factors that enterprises gain sustained competitive advantages in the knowledge-based economy. The performance evaluation of e-business system is significant because the process can help us find the defects and. obstacles of ebusiness system. Based on mathematics and human psychology algorithm, the Analytic Hierarchy Process (AHP) is a structured technique for dealing with complex decisions and project evaluation This paper presents an application of the AHP in the performance evaluation of e-business system by developing a fuzzy comprehensive evaluation model and a grey clustering method. In the last part of this paper, a case study is illustrated the application of the evaluation model and the evaluation process. [Copyright &y& Elsevier]

Abstract: The paper uses Oracle as the background database server and applies mainstream technology such as Struts to design and implement a training system based on WEB. The system can implement online study, online test, staff management, staff group management, curriculum management, curriculum system management, staff studying situation management, test management, test papers management and staff test score management.etc. The system fulfills the practical demand of the company training department and reaches the design goal in performance so that it can become the key measure to process daily business for the training department. [Copyright &y& Elsevier]

Abstract: Wireless Multimedia Sensor Networks (WMSNs) is comprised of video sensor, digital signal processing unit and digital radio interface. Owing to ubiquitously retrieve multimedia content such as video and audio streams, still images, and scalar sensor data from the environment, the Quality of Service(QoS) problem of WMSNs becomes a hot research. In this paper, we will discuss the parameters for QoS performance evaluation, classify some typical protocols which proposed in the literature both at home and abroad, give a comprehensive description of these algorithms or protocols, and compare them from the aspects of layered architecture, communication model, energy efficiency, etc. Finally, the paper also concludes with a discussion on the future directions and challenges in the areas of QoS routing in WMSNs. [Copyright &y& Elsevier]

Abstract: Digital Fountain code is a forward error correction code developed in recent years. The code does not need to know the channel information, and can be decoded with high probability. LT code is the first practical digital fountain code, it has fully inherited the advantages of digital fountain code. This paper introduces the concept and the classifications of Digital Fountain code, especially about the encoding and decoding process, the degree distribution and the application environment of LT code; the parameters of the degree distribution of LT code are discussed through the simulation, the optimization parameters of LT code are given and the importance of each parameter is analyzed; the paper has obtained the specific value of the decoding failure probability of Digital Fountain code; the effects of the amount of data received on LT code as well as the best amount of data have been studied; Finally, a model about how the Digital Fountain code can be used in the real application is given, make it gradually been used in the practical application. [Copyright &y& Elsevier]

Abstract: Performances of full-wave detectors used in ultra-wideband (UWB) communications have not been addressed in the literature. This paper discusses the basic signal detection scheme and error performances of this receiver architecture. The theoretical bit error probability is derived using Gaussian approximation that satisfies well in UWB systems. Simulation results are provided in the additive white Gaussian (AWGN) channel model which shows that the bit error rate (BER) of full-wave detectors is almost identical to energy detectors (EDs) with merely a small power disadvantage. Besides, this paper indicates that due to different features of signal detection techniques from EDs, it is potential for full-wave detectors to achieve an appropriate tradeoff between error performance and system complexity. [Copyright &y& Elsevier]

Abstract: This paper presents a secure spatial steganography system against some powerful spatial steganalysis by employing HVS characteristics and chaotic technique. Firstly, this paper gives the embedding model, and then specifies the two key points of the embedding model: HVS JND model and generation of embedding location, which make the proposed method more imperceptible and more anti-extracting. By the security analysis to the embedding model, the security of proposed method is proved. Finally, experimental results show our method''s better performance than conventional spatial embedding scheme. [Copyright &y& Elsevier]

Abstract: Shape optimization design has been paid more attention in many industrial fields, but the application of automatic method for naval ship hydrodynamic design has not reached the same level of maturity. Even so, it introduces numerical tools, combines with CFD and optimization methods, which contribute to ship design, can improve the ship performance, and reduce the cost of development and building. This paper proposes to apply the CFD technology to automatic optimization of hull form of naval ship, and builds hull form optimization frame based on CFD, to execute form optimization for sonar position of surface combatant –David Taylor model basin (DTMB) 5415 ship model. The result illustrates that the research of the paper has great value in engineering application. [Copyright &y& Elsevier]

Abstract: The paper analyses the performance of four kinds of control strategy on parallel hybrid active power filter (PHAPF) qualitatively, which has the best topology superiority on hybrid active power filter. On the basis of it, the paper proposes novel APF capacity analysis method on PHAPF, and the novel method provides theoretical support for quantitative analyzing the APF capacity under the different control strategy, and it plays an important part in the controlling the APF capacity and reducing the cost of PHAPF. [Copyright &y& Elsevier]

Abstract: Godson-3A as the latest multi-core generation of Godson microprocessor family targets to the low cost servers and high-performance computers. As Godson-3A adopts the scalable mesh of crossbar topology and provides extensive I/O support based on crossbars, we can implement the architectures of servers or computers in various ways. But for each design, the proper design and implementation of BIOS plays an important role in making full use of flexibility provided by the hardware design of Godson-3A. This paper introduces the two-level scalable architecture implemented inside Godson-3A, lists multiple architectures of Godson-3A systems, and discusses the realization of software routing configuration mechanism by the crossbar switch in detail. Based on the above analysis, this paper analyzes the design and implementation of BIOS to realize the correct functions and improve the performance of various Godson-3A systems. [Copyright &y& Elsevier]

Abstract: A fast development of high speed railways is witnessed in recent years as well as the performance of its wireless communication systems, GSM-R. In GSM-R systems, a large percentage of call outage is induced by handoff process. Thus, handover is a critical issue of reliability performance in GSM-R systems. Most of existing investigation and practical designs for handover in GSM-R systems are mainly based on single antenna without considering the specificity of the train as hard handover. In this paper, we take full use of the length of the train and propose a novel scheme of seamless fast handover based on Dual-Antenna. In this scheme, two antennas are respectively installed at the head and the end of the train and the proper coordination of the two antennas turn it to a soft handover. In the interlacing area of two antenna cells, the head antenna handover in advance while the end antenna connects to the current cell until the front antenna connect the new cell reliably. In this way, we can achieve a seamless and fast soft handover. This paper introduces the details of the scheme and analyzes the feasibility. Simulation results show that the proposed scheme is more efficient than existing schemes in terms of handover delay and reliability. [Copyright &y& Elsevier]

Abstract: E-commerce''s constant development has caused great changes to the enterprises’ logistics and the operation of supply chain. This change is embodied in the management of supply chain based on the electronic commerce characterized by Informatization and integration. The paper analyzes the insufficiency of traditional performance evaluation method which exists in the supply chain, discusses the supply chain management under the electronic commerce environment, and at the end of the paper, the author proposes system structure of the management performance evaluation of supply chain. [Copyright &y& Elsevier]

Abstract: The algorithm based on context similarity has the drawback that it will cost more time if not all the attributes are detected, this paper views the context attributes as attribute stream and the BOAS (Bayesian on the Attributes Stream) algorithm based on context knowledge is proposed in this paper. BOAS algorithm firstly calculates the undetected attribute of terrorism group identifier, and then uses conditional probability and Bayesian theorem to predict the future terrorist behavior. In this way, it avoids handling the undetected attributes in the original algorithm, but also avoids computing the context similarity based on distance function repeatedly. Thus, it improves the performance efficiency. The experiment result shows that BOAS algorithm proposed in this paper reduces computation time while it assures the accuracy of the prediction. [Copyright &y& Elsevier]

Abstract: This paper gives a novel temporal Tomlinson-Harashima Precoding (THP) and spatial detection joint processing algorithm for Multiple-Input Multiple-Output (MIMO) frequency selective fading channels. Generally spatial and temporal signals are processed at transmitter side, or at receiver side, both are very complex indeed. In this paper, we propose a novel temporal THP (T-THP) and spatial decision feedback equalization (S-DFE) detection joint processing technique, at transmitter, T-THP to each sub-channel of MIMO channel model is performed, through this step, the channel model is changed into flat fading MIMO channel; Then at receiver side, adopt MIMO detection to cancel interference from different antenna or multi-user, and at last, the estimated signal will be got. Using this solution, we can change the space and time 2-dimension''s operation into two 1-dimension''s operation separately, and in each space, the algorithm is relative simple. From algorithm analysis and performance comparison, we can see the validation and advantage of this method suggested in this paper [Copyright &y& Elsevier]

Abstract: A time synchronized SFN(Single Frequency Network) Adapter of CMMB(China Mobile Multimedia Broadcasting) system is proposed in this paper, which is designed based on the FPGA and associated with a PCI interface chip structure.This design improves the portability and upgrade performance of system by integrating all functions of the PCI controller,Adapter of SFN,ASI interface and GPS interface on one chip of FPGA and on chip of PCI interface.The process of design is described in detail and the implementation of the main functional modules is presented in this paper. [Copyright &y& Elsevier]

Abstract: This paper presents dynamic voltage restorer (DVR) with vector control strategy for mitigating power quality in power distribution systems. Whenever power quality problems, voltage sag/swell, occur DVR has to automatically detect and inject voltage components. The detection unit should be fast enough to know the variation of all phase voltages, including magnitude and phase, to trigger the DVR to inject appropriate voltage components with required phase angles within very short period of time. Here, control strategy adopted for driving the DVR plays and important role in its performance. Any delay in the process or incorrect injection would be harmful to sensitive loads that are vulnerable to voltage sag/swell. This paper illustrates vector control strategy based on decoupling control to enhance performance of DVR during the process of compensation. It was found out that voltage sags/swells can be corrected faster with the proposed control strategy compared to conventional methods. [Copyright &y& Elsevier]

Abstract: This paper applies the method of factor analysis to construct the indicator system of low carbon economy and evaluates the performance of development of low carbon economy of 15 resource-based cities. The paper documents that the development performance of low carbon economy of Daqing ranks No. 3 among 15 cities, performance of inter-industry adjustment ranks No.14, energy efficiency ranks No.3, effectiveness of environmental improvement ranks No.1, and performance of secondary industry adjustment ranks No.10. The results show that Daqing has advantages in energy efficiency and effectiveness on environmental improvement, and but needs to improve its performance of in inter-industry adjustment and secondary industry adjustment. [Copyright &y& Elsevier]

Abstract: Portland cement can play a major role in providing cost-effective, long-term zonal isolation for CO2 capture and storage (CCS) used to mitigate climate change. However, achieving zonal isolation with Portland cement under supercritical CO2 environment for the required 1,000 year trapping period may be challenging. Some laboratory researchers report that Portland cement disintegrates when exposed to CO2, leading to potential leakage into the atmosphere or other to underground zones. Other researchers cite Portland cement samples from 30–50 year old CO2 EOR wells where sealing integrity was maintained, even though carbonation was found. In this paper we will discuss reasons likely for this disparity between research lab test results and actual well performance data. Carbonation of Portland cement is a thermodynamically favorable process and therefore difficult to avoid. But the effects can be minimized by various reactive chemical components optimized for the specific thermodynamic conditions. Our research shows partial carbonation of Portland cement is not detrimental unless the mechanical integrity is insufficient to provide effective zonal isolation. For these studies we have developed CO2 treatment test cells capable of producing conditions up to 200 °F and 2,000 psi. In addition, various analytical instruments including x-ray diffraction (XRD), thermo-gravimetric analysis (TGA) and mechanical properties measurement devices have been used for this study. In this paper we will discuss the importance of understanding the percentage of carbonation and depth of CO2 penetration, and how to control these factors by optimizing the cement blend. Interestingly, we found the amount of Portlandite { Ca(OH)2} that forms due to cement hydration and the cement-to-water ratio dictates the depth of penetration as well as percentage carbonation. The implications of this in relation to the long term chemical integrity of the cement sheath under downhole CCS conditions is discussed. This paper also includes the results of recent studies on the changes in mechanical properties of a properly optimized Portland cement blend for a period of up to one year. During this period, measurements were made at different time intervals to examine cement specimen treated with CO2 at 200 °F and 2,000 psi in the presence of water. The results show carbonation without any sign of loss of mechanical or sealing integrity that could lead to zonal isolation failure. Results from a separate set of experiments show the following: (1) Carbonation could be minimized by reducing the Portland cement content by adding Pozzolanic materials and by reducing the permeability and (2) Carbonation could help heal micro-cracks that may be caused by various well operations or ageing. However, such carbonation-induced healing is limited only to a certain width of cracks. In summary of this research, it is recommend that: (1) a high quality primary cement job be performed in adherence to all industry best practices; (2) the cement blend be properly optimized to minimize long-term CO2 corrosion; and (3) the sheath be designed for long-term mechanical integrity. This paper will discuss a comprehensive approach that may be taken to help ensure longer-term effective zonal isolation in new CO2 wells and remedial solutions for old wells and for plugging and abandoning wells. [Copyright &y& Elsevier]

Abstract The solar thermoelectric generation（STEG）cogeneration system can provide heating and electric power simultaneously. Precedent studies on the STEG system were focused on getting higher electrical efficiency of the system and creating a new record. Optimization of thermal performance and evaluation of thermal efficiency are usually completed by calculation or numerical simulation. In this paper, a novel design of STEG cogeneration system was proposed. The system can work in three modes according to seasonal demand of hot water and electric power. A series of experiments were carried out in different working modes under variable conditions to evaluate the performance of the system. The results show that the system can generate 0.2 kW·h of electrical energy and about 100L of hot water at 41 °C in 1 day when solar irradiation is 1000 W/m2. The collector efficiency and electrical efficiency are calculated to be 42.2% and 2.1%, respectively. [ABSTRACT FROM AUTHOR]

Abstract Organic Rankine Cycle (ORC) is known as one of the best method amongst the other low-grade energy recovery methods. ORC can be applied for different applications such as geothermal, solar thermal and waste heat. However, the application of ORC in these applications requires the selection of suitable working fluid for better performance. So, this paper focuses on performance evaluation of ORCs for different working fluids. The modelling work was performed using MATLAB and, a thermo-physical database, REFPROP. The evaluation is performed based on the performance of the working fluid. The results reveal that MD2M & cyclopentane for temperature ranges 50 - 100 ⁰C, butane, neopentane & R245fa for 100 - 150 ⁰C, ethanol, methanol and propanone for 150-200 ⁰C and Water, m-Xylene and p-Xylene for 200 - 320 ⁰C are better working fluids for energy extraction. [ABSTRACT FROM AUTHOR]

Thermo Vapour Compressor TVC is the heart or prime mover of Multi-Effect Desalination MED system, it is also described as a steam ejector. Steam ejector is an economical device that utilizes high pressure steam to compress low pressure steam without any rotating parts or external power sources. The ejector performance is highly dependent on its geometry and operating conditions. The aim of the present work is to design and obtain steam ejector geometry, based on pre-specified operating conditions, and to investigate the flow behavior inside the ejector by using Computational Fluid Dynamics CFD through using “ANSYS FLUENT 14.5” software. In first section of this paper, 1-D mathematical model is carried out to predict the ejector geometry at designed operating conditions. The second part, describes the flow behavior inside the designed model of the ejector by CFD. CFD is a most reliable tool to reveal the phenomenon of the mixing process at different parts of the supersonic turbulent flow ejector and to study the effect of operating conditions on the effective ejector area. Obtaining such effects, using experimental work, is much costly and difficult. Finally, the results show the effect of the operating conditions on the entrainment ratio and the critical back pressure. [ABSTRACT FROM AUTHOR]

Thermo Vapour Compressor TVC is the heart or prime mover of Multi-Effect Desalination MED system, it is also described as a steam ejector. Steam ejector is an economical device that utilizes high pressure steam to compress low pressure steam without any rotating parts or external power sources. The ejector performance is highly dependent on its geometry and operating conditions. The aim of the present work is to design and obtain steam ejector geometry, based on pre-specified operating conditions, and to investigate the flow behavior inside the ejector by using Computational Fluid Dynamics CFD through using “ANSYS FLUENT 14.5” software. In first section of this paper, 1-D mathematical model is carried out to predict the ejector geometry at designed operating conditions. The second part, describes the flow behavior inside the designed model of the ejector by CFD. CFD is a most reliable tool to reveal the phenomenon of the mixing process at different parts of the supersonic turbulent flow ejector and to study the effect of operating conditions on the effective ejector area. Obtaining such effects, using experimental work, is much costly and difficult. Finally, the results show the effect of the operating conditions on the entrainment ratio and the critical back pressure. [ABSTRACT FROM AUTHOR]

Abstract: This paper introduces the overview of China''s solar water heater industry. The share of non-pressurized compact SWHs is about 80%. Due to its low pressure-resistant, the thermal performance testing for non-pressurized SWHs is not as easy as the pressurized system. The pressure for the supplied water for the testing must be lower enough to ensure the tested SWH cannot be damaged. So, except the method identified in ISO 9459-2, China national standard introduces another way to test the thermal performance for the non-pressurized SWHs. It uses a pump to mix the water in the non- pressurized water tank, records the temperature at the beginning and the end of the test, and calculates the heat gain under the daily irradiation. This test method is much closer to the real using situation for these SWHs. In 2012, China will issue a new national standard for solar water heaters Minimum allowable values of energy efficiency and energy efficiency grades for domestic solar water heating systems. This standard requires all products sold in China should be labeled with the energy efficiency grade. The energy efficiency grade is calculated with the value obtained by the thermal performance test. A complicated test system like a testing laboratory is not suitable for the factories in China. A compact automatic test facility to assist the factory to determine its products’ energy efficiency grade is needed. This test facility has user-friendly interface developed with LabView, can perform the test and print the test report automatically. [Copyright &y& Elsevier]

Abstract: From 2009 to 2011, the Ministère des Ressources naturelles et de la Faune (MRNF), which is the ministry responsible for natural resources and wildlife in Quebec, supported a pilot project aiming to develop the solar domestic water heater (SDWH) market in Québec. Seventy participants took part in this program, of which 23 agreed to be part of a campaign for monitoring the energy performance of their solar system. The Laboratoire des technologies de l’énergie (LTE) of the Hydro-Québec Research Institute was commissioned by the MRNF to conduct the monitoring. The main results of the study are published in this paper. [Copyright &y& Elsevier]

Abstract: This paper presents a study of the effect of key design parameters on energy performance of two-storey single family dwellings and small scale neighborhoods, in a mid-latitude northern climate. Design parameters include the geometric shapes of dwelling units and their assemblage in a neighborhood. The effects of the design parameters are presented in a matrix that relates design parameters to performance criteria. An example for an evaluation system of the performance of design alternatives is proposed, based on design parameter effects and weights assigned to different performance criteria. Performance criteria considered are heating and cooling energy consumptions, solar energy generation, and shift of peak of electricity generation. The evaluation system is a decision-aiding tool, which enables selection of design parameter values leading to optimal performance for the assumed performance criteria. A design methodology is proposed for the design of solar optimized housing units and neighborhoods, based on the matrix of results and the evaluation system. [Copyright &y& Elsevier]

Abstract: The aim of this paper is to explore the concept of Solar Urban Planning with the goal of developing an operative methodology to achieve the best conditions towards Zero Energy Building (ZEB). In the last two centuries there has been a transformation in the form of cities, from being relatively compact to a confused urban sprawl. By 2020, all new buildings constructed in the European Union will have to be “nearly zero energy” in response to the Energy Performance of Building Directive. The ZEB goal is technically achievable but dependents on various conditions of the urban structure. By 2050, the population will grow from 7 to 9 billion, the facts are clear and the time to act is now. The task to provide high solar performances buildings could be attained in a better way if the urban planning process integrates a solar energy approach to both new and existing urban environments. A “new step” that determines the solar potential of an urban area, implements a model connected to the needs of buildings and their capacity to produce energy from solar resource integrating solar analysis with parametric urban design, represents a useful tool to be added into the conception phase of urban planning. The methodology has been applied to a case study in Portugal to plan the correct orientation and form of new buildings to guarantee the optimal efficiency of photovoltaic roof and façade systems and calculate their solar energy production. Considering the importance and the complexity to minimize the use of cooling system and reduce the buildings energy consumption, multiple actions are required. Solar urban design is a “new phase” of sustainable urban planning, a phase that has wide horizons of development and could provide new solutions to the worlds energy problem by reducing its consumption and improves the performance of future buildings. [Copyright &y& Elsevier]

Abstract: Impact of users on thermal behaviour of a building and a building''s impact on the use of different spaces are two aspects that are subject of post occupancy evaluation of the present paper. The building was designed according to passive concepts, including Insulated envelope and internal thermal mass; also computer simulations were used to optimize thermal performance of different components of the design. The evaluation was done by using quantitative method to document climate and interior lighting. A qualitative method was also used for analysis of building use and perception of indoor climate by users. High windows were placed in the hall and lobby for night flush to cool the building during summer. However, the difficulty of opening them had led that night ventilation was never practiced. In winter, less window''s areas would be sufficient to satisfy the thermal comfort during the day while ensuring a sufficient level of natural lighting. Daylight level measured in the morning shows that the level of illumination is acceptable; however it remains below the required minimum during the afternoon during fall, winter and spring. Small to medium windows, (4-10% of floor area) on west orientation could improve the daylight during the afternoon. Also, a late closing of the youth club would be desirable for the spring, summer and fall when days are long. The results of the interviews describe a high level of satisfaction from users with regard to indoor climate. Bioclimatic design has a positive impact on the use of the youth. [Copyright &y& Elsevier]

Abstract: This paper is summarizing the results of a research carried out for assessing thermal performances of Trombe walls integrated in lightweight constructions. Phase-change materials, substituting heavy thermal storage mass, have been used in order to improve the energy performance of the system. For evaluating the device sensibility to external environmental conditions, five Australian cities (representative of five different climatic zones) have been considered. Furthermore, variations of PCM position in the external envelope and of melting point temperatures have been taken in account in order to define the most suitable technology for each climatic area. [Copyright &y& Elsevier]

Abstract: The European Union has set a goal that the energy use in the built environment shall be reduced by 41% to the year 2050 compared to 2005-2006. This could introduce new opportunities for solar thermal systems in cold countries. In such countries, like Sweden and Canada, the economy in solar thermal collector installation projects is often spoiled by the fact that most of heating energy demand of the building occurs during periods when the available solar energy is low. The present paper investigates the performance of solar thermal systems subjected to different quota between space heating and domestic hot water demand (DHW). This study investigates the performance of a solar thermal system integrated to four different buildings with varying heating loads in two different locations, Sweden and Canada. Models of single family houses are created which are able to simulate the total heating demand with different heating demand profiles but the same DHW demand. Simulations are performed in TRNSYS, an advanced tool used to simulate transient systems. Results indicate that solar combisystems tend to generate more useful energy and therefore be more cost effective when installed in buildings with higher heating demands. [Copyright &y& Elsevier]

Abstract: The paper investigates experimentally the thermal performance of a ventilated double skin facade (DSF) with phase change material (PCM) in its air channel, during the heating season in the Mediterranean climate. Two identical house-like cubicles located in Puigverd de Lleida (Spain) were monitored during winter 2012, and in one of them, a ventilated facade with PCM was located in the south wall. The ventilated facade can operate under mechanical or natural ventilation mode and its thermal control depends on the weather conditions and the energetic demand of the building. The experimental results conclude that even though the use of the ventilated facade with PCM improves significantly the thermal behaviour of the whole building (working as a heat supplier in free floating tests, and reducing significantly the electrical consumption of the HVAC systems), these improvements might be increased if a thermal control is used. [Copyright &y& Elsevier]

Abstract: This paper presents the analysis of the experimental tests performed with an absorption refrigeration advanced Solar-GAX system, designed for 10.5kW (3 Ton) of cooling using ammonia-water mixture. The system designed for operation at heat source temperatures of around 200°C, consists of an absorber and generator of a falling film type and air cooled finned tube condenser and absorber, being an option for areas with water scarcity. Heat source temperatures of 160°C were established to simulate the conditions of using solar thermal concentrating technology to supply heat the system, this means the system operating at partial load. Cooling capacities from 3 to 7kW were obtained, with an average coefficient of performance (COP) of 0.37. Thermal stability was rapidly reached, after only 15minutes of operation. [Copyright &y& Elsevier]

Abstract: The Drake Landing Solar Community in Okotoks, Alberta, Canada utilizes a solar thermal system with borehole seasonal storage to supply space heating to 52 detached energy-efficient homes through a district heating network. Systems of similar size and configuration have been constructed in Europe, however, this is the first system of this type designed to supply more than 90% of the space heating with solar energy and the first operating in such a cold climate (5200 degree C-days). Solar heat captured in 2293 m2 of flat-plate collectors, mounted on the roofs of detached garages, is stored in soil underground and later when needed for space heating, is extracted and distributed through a district system to each home in the subdivision. Independent solar domestic hot water systems installed on every house are designed to supply more than 50% of the water heating load. Annual greenhouse gas emission reductions from energy efficiency improvements and solar energy supply exceed 5 tonnes per house. The seasonal storage utilizes approximately 34,000 m3 of earth and a grid of 144 boreholes with single u-tube heat exchangers. The system is configured to maintain the centre of the field at the highest temperature to maximize heating capacity and the outer edges at the lowest temperature to minimize losses. A short -term thermal storage consisting of 240 m3 of water is used to interconnect the collection, distribution and seasonal heat storage subsystems. The system has undergone detailed monitoring since it was brought into service in July 2007 to characterize its performance and to improve the TRNSYS model employed in its design. A solar fraction of 97% in its fifth year of operation, convincingly confirms the design target, a solar fraction of more than 90% in year five, has been met. This paper describes the system and its operation, presents 5 years of measured performance and compares those results against the TRNSYS predicted performance for the same period. [Copyright &y& Elsevier]

Abstract: This paper focuses on the analysis of the operation of a solar cool ing system based upon an adsorption chiller. The air-conditioned building studied is a laboratory located in a temperate climate region (Belgium). The monitoring reveals thermal and electrical coefficient of performance (COP) of the cooling system for different time scale (10s to1 month). The whole system including solar collectors, adsorption machine, recooling unit and hot storage is simulated. The models are then confronted to the measurements. Measurement period is shared between 2011 and 2012. Enhancements have been achieved during winter 2011 to have a more efficient system operation. The aim of this experimental work is to describe, for both measurement periods, the influence of operating conditions on the energy efficiency (thermal behavior and electrical consumption). On the simulation point of view, the main objective is to find accurate models for all the components. The adsorption chiller model is not yet precise enough to evaluate the performance of solar cooling in other conditions. [Copyright &y& Elsevier]

Abstract: Energy requirements for new buildings show the strong direction given by UE Directives to improve energy performance in buildings according to economic feasibility. Nowadays it is possibile to const ruct new buildings reaching a substancial reduction in energy consumption containing prices and time for the construction. In architectural competitions are always included architectural, energy and economic parameters of quality which are decisive in the success of the project design. A Housing Contest to collect projects with high performance and low cost for residential buildings for the Municipality of Comune di Milano, Italy, and the future construtions in the local area was launched by the to involve architects and professionals on the future development of the urban landscape giving specific requirements to achieve high performance. These requirements were focused on energy quality, acoustic quality, quality of the building site, guaranteed time schedule, prefabrication, economic affordability in comparison with the market trend of costs. The project presented in the paper is one of the chosen building by the Municipality to represent a pilot project for possible future constructions. In the Contest all the design group were in team with a builder to verify and guarantee the costs of the construction. The high energy performance required coupled to the low cost assured by the projects gave the Municipality a good example of how is possible to fulfill quality levels recommended by EU Directives and national regulations. In the Contest a high energy performance for heating was compulsory. The project described in the following paragraphs not only fulfill this energy requirement but also is almost self-sufficiency since it provides the energy for heating, cooling and common electrical demand. [Copyright &y& Elsevier]