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This study deals with the urban microgrid energy management that is dedicated to individual and collective self-consumption by providing flexibility to the distribution grid (DG). The proposed urban community microgrid is interconnected to a DG and it consists of an association of centralized storage units (called community energy storage system), community intermittent renewable generation, and intelligent energy management system (EMS). One of the main advantages of urban microgrid is that, in case of faults in the DG, it can cut existing interconnections and continue to supply the responsible community in the island mode. In this study, the developed urban microgrid EMS is based on the predictive control management through the day-ahead optimal power flow (DA-OPF) strategy. The main contributions of this work can be defined by two points. The first point is related to a development of the DA-OPF strategy for the urban microgrid based on the intelligent deep learning data forecasting and the mixed-integer nonlinear programming optimization methods. The second point concerns a development of an optimization function integrating the concept of ancillary services of DG flexibility. Experimental results and economical evaluation are presented in this article. By using the proposed strategies, it results in an important electricity price reduction for the considered urban microgrid, compared to a conventional distribution system and basic operation schemes.

This research presents an example of the energy transition process application on conventional French urban communities and particularly, its possible integration into the Urban Communities Smart Grids (UCSG). For this, it was chosen one of typical urban community - Alfortville (94140), Paris region, France. The aim is to define all UCSG components and the adapted UCSG structure for the further application of the efficient, renewable, economic and resilient Day-Ahead Optimal Power Flow (DA-OPF) energy management, giving the opportunity to get additional distribution grid flexibility. The integration of UCSG’s DA-OPF management requires the centralized control and involves the integration of centralized battery storage systems (CESS) and distributed PV generation. It was determined the optimal penetration rate and size of distributed PV and CESS. The final considered UCSG simplified scheme and its components was defined. The efficient DA-OPF management strategy was applied on the obtained community scheme. The DA–OPF is based on a data forecast system that uses a Deep Learning (DL) Long Short-term Memory network (LSTM) and is formulated as a mathematical Mixed-Integer Nonlinear Programming (MINLP) model. The real data simulation UCSG showed significant benefits and an electricity price reduction for the considered urban community compared to a conventional case, as well as the easy applicability of proposed method. The efficiency and versatility of this research allow its easy application to others similar urban communities under UCSG integration.

This article deals with the world energy transition process and in particular with the European target to reach the distributions grids additional flexibility. It introduces notions of flexibility, its advantages and the actual crucial utility for the distribution grid, also as new sources of flexibility thought demand side ancillary services. Due to the distributed renewable energy deployment, smaller and smaller consumers become prosumers and can also provide additional electricity or ancillary services to the distribution grid among conventional and centralized sources. Actual research studied application of previously presented the up and down-regulation flexibility ancillary services algorithm for the prosumer’s battery energy storage system participation. The practical evaluation applied this algorithm on the real prosumers case, situated in the Paris region, France, with the aim to evaluate the attractiveness, feasibility and practicability of ancillary services participation in the current French legislation frameworks. The technical and economic analysis of the real data evaluation presents from one side the economical attractiveness of this service participation for the considered real prosumer without degradation of its battery storage lifetime. From another side, it allows the distribution grid to achieve much needed additional flexibility.

STUDY QUESTION How efficacious is transplantation of ovarian cortex previously exposed to chemotherapy? SUMMARY ANSWER Prior exposure to chemotherapy did not disrupt the function of cryopreserved ovarian tissue after transplantation. WHAT IS KNOWN ALREADY Ovarian tissue cryopreservation (OTC) followed by ovarian tissue transplantation (OTT) is an efficacious technique for restoration of female fertility. At least 130 children have been born following this procedure. To date, little is known about the efficacy of OTT in patients exposed to cancer chemotherapy prior to OTC. STUDY DESIGN, SIZE, DURATION This study evaluates the recovery of ovarian function and fertility in 31 consecutive patients who had received OTT, between 2005 and 2015. PARTICIPANTS/MATERIALS, SETTING, METHODS Thirty one patients, wanting children, were transplanted with autologous ovarian cortex, among which 22 patients (71%) had been exposed to chemotherapy before OTC. Recovery of ovarian function was considered total once menstruation occurred. Ovarian function recovery (OFR), ovarian graft survival, and incidence of pregnancy were related to previous chemotherapy exposure, type of chemotherapy and graft characteristics (number of grafted fragments and follicular density). MAIN RESULTS AND ROLE OF CHANCE The amount of ovarian tissue collected was the only parameter to show any significant change between patients with versus without previous chemotherapy. At 1 year after OTT, the cumulative incidence of OFR was 83% (93% in patients exposed to chemotherapy and 67% in others (P = 0.14)). A low follicular density (

The present paper deals with the experimentation of a hydrogenated Palm Kernel vegetable fat as a novel bio-based Phase Change Material (PCM). This bio-based PCM with 26.53 °C of melting temperature and 74.35 J/g of the latent heat capacity of fusion was recovered from abundant and renewable underused feedstocks. The purpose is to trap this PCM without leakages into the internal microstructure of a prepared supporting material (matrix) first; and then to propose the resulting composite-PCM for a practical application of passive TES in building envelopes. This matrix was prepared from available, low-cost and eco-friendly components. However, natural clay and cellulose fibers were principally used in the preparation of the PCMs’ supporting material. 53 wt percent (wt%) of the bio-based PCM were successfully incorporated in this matrix after the direct immersion method thanks to the capillary and surface tension forces . Differential Scanning Calorimetry (DSC) results showed that the Thermal energy storage characteristics of the obtained composite-PCM are suitable for building applications. This melts at 27.33 °C with 40.27 J/g of latent heat capacity of fusion. Thermo Gravimetric Analysis (TGA) revealed that the prepared composite-PCM maintains a good thermal reliability in its working temperature range. The Hot-Disk results proved that the addition of graphite improved its thermal conductivity . Fourier Transformed Infrared Spectroscopy (FT-IR) confirmed the chemical stability of the prepared material. Finally, Scanning Electron Microcopy (SEM) showed that the bio-based PCM is successfully retained by the microstructure of the prepared matrix after the impregnation process.

The use of bio-based Phase Change Materials (bio-PCM) is an effective mean to enhance the building’s Thermal Energy Storage (TES) capacity with low-cost and eco-friendly materials. The present study encompasses the results of thermal, physico-chemical and mechanical characterizations of a novel composite bio-PCM developed in the laboratory to improve the thermal comfort in the building’s indoor environments. We tested a non-cocoa Vegetable Fat (VF) recovered from confectionery manufacturing industry. The VF is incorporated into a mineral board prepared from Natural Clay (NC) and Cellulose Fibers (CF). Phase change temperatures and TES capacity of the composite at melting and freezing cycles are measured with Differential Scanning Calorimetry (DSC) to be at 34.83 °C, 22.34 °C and 60.41 J/g, 62.39 J/g respectively. The Scanning Electron Microcopy (SEM) showed that the VF was evenly distributed into the microstructure of the mineral board. Results of thermal stability tests (more than 2000 cycles) confirmed that the composite bio-PCM is thermally and chemically stable. The compressive strength of the supporting material was slightly reduced after the incorporation of the bio-PCM, but it remains within the accepted limits for non-structural building applications. This research on thermal and mechanical properties has revealed that this homemade PCM panel could be a potential candidate for an application in buildings of hot and dry climates.

This study works with the application of the Demand Response (DR) program in the residential building sector. DR helps to resolve many power system problems of Distributed Grid (DG) as the congestion in the generation, the lack of flexibility and the high electricity demand during the Peak Hours (PH). The DR is already largely applied in the industry sector. Nevertheless, in the residential building sector, which represents around 35 % of European energy consumption, its large intronization actually is possible due to systems of smart managing and metering, dispatching and automation. Buildings can reach supplemental economic benefits from participation in the DR program additionally to energy efficiency or/and building insulation improvement. This work studies the possibility of economic benefits from Ancillary Services (AS) DR program participation due to the Building Thermal Inertia (BTI). The real test case produced with the real smart home test platform demonstrates the considerable attractiveness of this AS method. It brings additional economic benefits for the final householders with the respect of thermal comfort of the building. For DG this method brings an additional gain of flexibility which it really needs to compensate the increasing large penetration of renewable energies.

This study presents a method to consider residential Battery Energy Storage Systems (BESSs) for providing Ancillary Services (ASs). Residential prosumers with Renewable Energy Sources (RESs) can use BESS to increase the local self-consumption. To obtain additional benefits, BESSs can also be managed to provide ASs. This brings additional benefits to prosumers and provides additional flexibility to the Distribution Grid (DG). As individual participation in the electricity market is not economically feasible, prosumers should be aggregated and operated by a local aggregator. The aggregator intercommunicates with the System Operator (SO), analyses the possibility of auxiliary services provision, and can make an offer/bid to the Ancillary Service Market (ASM). Once the offer/bid is accepted, the aggregator can operate the BESSs of the prosumers accordingly. This study analyses the economic attractiveness of prosumers' participation in the up and down-regulation.

In this paper, an innovative method for managing a smart-community microgrid (SCM) with a centralized electrical storage system (CESS) is proposed. The method consists of day-ahead optimal power flow (DA–OPF) for day-ahead SCM managing and its subsequent evaluation, considering forecast uncertainties. The DA–OPF is based on a data forecast system that uses a deep learning (DL) long short-term memory (LSTM) network. The OPF problem is formulated as a mathematical mixed-integer nonlinear programming (MINLP) model. Following this, the developed DA–OPF strategy was evaluated under possible operations, using a Monte Carlo simulation (MCS). The MCS allowed us to obtain potential deviations of forecasted data during possible day-ahead operations and to evaluate the impact of the data forecast errors on the SCM, and that of unit limitation and the emergence of critical situations. Simulation results on a real existing rural conventional community endowed with a centralized community renewable generation (CCRG) and CESS, confirmed the effectiveness of the proposed operation method. The economic analysis showed significant benefits and an electricity price reduction for the considered community if compared to a conventional distribution system, as well as the easy applicability of the proposed method due to the CESS and the developed operating systems.

Resumen: En base a simulaciones térmicas dinámicas con el software EnergyPlus se propone un módulo experimental de un espacio habitable para el poblado de Imata, Perú, a 4519 msnm, con condiciones climáticas severas de muy bajas temperaturas. Se realizó simulaciones para cinco configuraciones del módulo, añadiendo sucesivamente componentes bioclimáticas, tales como mejoras en el aislamiento de la envolvente, tragaluz e invernadero adosado. Para el mes de más bajas temperaturas, la temperatura media en el módulo de mejor configuración es 11 °C superior a la temperatura media en el módulo correspondiente a espacios habitables típicos de Imata. La temperatura nocturna promedia mínima es 18.4 °C superior a la correspondiente temperatura exterior (- 4 °C). Para mantener en el interior una temperatura de 16.3 °C (modelo adaptivo), se requiere, en promedio anual, una energía diaria de 12 kWh para el módulo típico y 1 kWh para el mejor diseño. Abstract: Based on dynamic thermal simulations with the EnergyPlus software, an experimental module of a rural dwelling is proposed for the village of Imata, Peru, at 4519 meters above sea level, with severe climatic conditions of very low temperatures. Simulations were carried out for five module configurations, successively adding bioclimatic components, such as improvements in the insulation of the enclosure, skylight and attached greenhouse. For the month with the lowest temperatures, the average temperature in the best configuration module is 11 °C higher than the average temperature in the module corresponding to typical Imata houses. The minimum average night temperature is 18.4 °C higher than the corresponding outside temperature (- 4 °C). To maintain a temperature of 16.3 °C inside the module (adaptive model), on annual average, a daily energy of 12 kWh is required for the typical module, and 1 kWh for the best design.

This study aims to develop a novel composite Phase Change Material (PCM) using eco-friendly and low-cost components for an application of improving thermal inertia of building envelopes. The Coconut fat recovered from underused feedstocks was selected as a bio-based PCM for its good Thermal Energy Storage (TES) characteristics. This bio-based PCM was incorporated in a composite matrix prepared in the laboratory from natural clay and cellulose fibers. The direct immersion method with no vacuum treatment was followed as a simple incorporation process of the bio-based PCM into its matrix. The results of thermal and physicochemical characterizations show that the prepared composite-PCM has the potential to be used for passive TES in building envelopes in order to enhance their thermal inertia.

This research work encompassed the results of experimentation of an innovative composite (Plaster/white Vaseline) for indoor thermal regulation of physiological birth rooms using the Latent Heat Thermal Energy Storage (LHTES) concept. The indoor temperatures of these specific sanitary rooms need to be continually stabilized approximately at 35 °C. Accordingly, white Vaseline (petroleum jelly) was recovered from health facilities and then tested as an alternative PCM for a LHTES application at constant temperatures. The white petroleum jelly used in this work is mainly composed of microcrystalline wax and liquid paraffin; its phase change temperatures were found to be respectively at 36.56 °C and 35.53 °C for melting and solidification cycles with an enthalpy value of 95.38 J/g (±1.23). In addition to these suitable thermal properties, the substance is safe and available at low-cost. A mineral matrix prepared essentially from plaster was experimented to trap the PCM into its microstructure in order to prevent any risk of leakage during the phase change process . Finally, the innovative composite (Plaster/white Vaseline) underwent thermal and physico-chemical characterization tests that identified its properties and revealed a potential efficiency of the novel material for passive thermal regulation of physiological birth room's indoor environments.

The adobe is a widely used traditional material in popular constructions in rural areas of Peru and more generally in Andean countries. In order to increase comfort and energy efficiency of constructions, it is necessary to better know the thermal characteristics of the adobe, seen as a bio-composite material. Different adobes have been studied. Effective thermal conductivity and heat capacity were measured by means of a hot parallel-plate method. Density was estimated using a pycnometer and measuring physical dimensions and mass of each sample, which allowed the calculation of thermal effusivity and diffusivity. Some numerical simulation results displayed good agreement with experimental outcomes. The work presented here has implications for future studies of this traditional building material and might potentially help solving the problem of sustainable housing.

This paper deals with energy management in the urban microgrid dedicated to individual and collective self-consumption. This microgrid is connected to the national grid, with a possibility of bidirectional power flow. The studied microgrid consists of some building integrated photovoltaic systems, a community photovoltaic field and a community storage unit. The provided household devices and public services can be classified in three categories, namely as adjustable, schedulable, and critical loads. In this paper, a concept of self-consumption in urban areas is studied and the decision support laws in the management of energy flow are developed and proposed. The paper addresses aspects related to the overall supervision of the system, whose performance depends on the quality of the means of real time communication and information exchange. The study is performed according to a methodology that is based on a load forecasting methodology to develop the Energy Flow Management algorithm, which is validated using an experimental test bench. As contribution, this paper proposes a development of an optimized energy management strategy in an urban self-consumption microgrid based on an intelligent load forecasting method. The results are presented and analysed in this paper.

Objective To describe our surgical techniques for laparoscopic ovarian tissue harvesting and orthotopic ovarian cortex grafting (LOOCG). Design This video article uses surgical cases to demonstrate the detailed surgical techniques. Institutional Review Board approval was not required for this video presentation. Setting University hospital. Patient(s) Patients presenting with indication for fertility preservation by means of ovarian tissue harvesting and orthotopic ovarian cortex grafting (in case of setting up a high risk of gonadotoxicity treatment or patients presenting with a pathology with risk of premature ovarian failure). Intervention(s) Ovarian tissue harvesting: The entire ovary is harvested by placing an EndoGIA stapler to ensure the control of infundibulopelvic ligament and then, after reloading, the section of the mesovarium. LOOCG one-step procedure: A large and superficial incision of the peritoneum is performed to create a peritoneal pocket. The fragments of ovarian cortex are secured with the use of nonresorbable surgical wire (Prolene 5.0) and introduced into the peritoneal pocket. The peritoneum is not closed after placing the graft. Main Outcome Measure(s) Value and feasibility of LOOCG. Restoration of endocrine function and fertility results. Result(s) Thirty-four patients were included from November 2011 to October 2017. LOOCG restored ovarian endocrine activity in 88.2% of cases. Ten patients had become pregnant (29.4%), and the same number gave birth to at least one child. Conclusion(s) Our surgical approach is simple, safe, and reproducible and seems to be as effective as previously described techniques. It deserves to be proposed to patients eligible for ovarian cortex grafting.

International audience

This paper presents a rural exemplar house built in San Francisco de Raymina (a high Andean village 3700 masl) in southern Peru that integrates passive and sustainable solar heating techniques. A climatic analysis of this village was carried out using measurements of meteorological parameters recorded throughout a whole year. The annually averaged temperature, relative humidity and horizontal daily solar energy were 8.3 °C, 73.1% and 5.2 kWh/m2, respectively. The temperatures outside and inside the most rural dwellings are almost the same, so they do not offer any protection specially, during nights when the temperature can reach values below zero. The thermal behavior of the house was modeled with the m2m tool, and an experimental validation was carried out. With the use of m2m, it was possible to create an energy balance during the month of June 2014 (the winter cold and dry season) to determine the energy loss/gain contributions by each wall and to assess how air exchanges (the flow rates of which were deduced using an inversion approach, as they could not be directly measured) between the exterior and interior influence the thermal behavior of the whole house. Infiltration contributed approximately 48.6% of the daily energy losses, while the main solar gains were from the skylights (21.8%) and the adobe walls, which absorbed heat during the day and released heat at night.

Economic growth and the development of global markets have been coupled with energy use, which have caused an increase in global energy demand and created pressure on the supply of energy resources. This special volume section reports advances being made towards sustainable cleaner production and sustainable energy options. The section presents a selection of papers that show leading examples of the application of sustainable management, green production, and renewable energy. An overview framework is proposed to categorise the papers and to show key actors, factors and technologies for resource efficiency, cleaner production and sustainable energy. The themes covered by the papers include drivers of such sustainable practices. Five of these papers focus on the role of technology, regulatory framework, and customers' efforts in fostering the development and adoption of greener technologies. Another group of seven papers gives examples of on how to use green chemistry and cleaner energy sources such as biomass to foster transition to sustainable production. The last paper addresses the effect of environmental practices on firm's performance. The special volume section highlights the importance of multidisciplinary approaches that integrate social and technological perspectives to solve current sustainability problems and to promote the development of sustainable energy and sustainable production.

In general cases, particularly in developing countries, the weakness of the national electric grid is due to overloading, infrastructures aging, high temperatures and bad weather. In such systems, the interruptions of electricity supply can take several hours to days. To prevent the power deficit, consumers can use diesel generators that are very noisy and highly polluting. But, as alternative, renewable energy sources and storage devices can be used for load shifting. This can help to improve the grid resiliency and the supply continuity. But, to do this, it is necessary to have efficient methodology of weakness analysis and resiliency factors estimation. In this paper, experimental data are used to define the main parameters of the system performance based on the IEEE Std Std 1366TM-2012 indexes.

Over the world, some rural people and communities are facing a limited access of energy services. It is very costly and not profitable to connect these areas national electrical grid. So, the use of the renewable energies can be an interesting alternative. In this paper, design of a photovoltaic system is studied by applying an optimization method. The study case is based on a centralized PV power production to supply energy to distributed rural communities’ loads. The design of PV panels, storage batteries, power converters and security devices can be very constraining. For this reason, multicriteria optimization method can be applied to the system parameters by using different configurations and operating scenarios. These can take into account the energy and power needs of each community activities and the natural resources (water access, solar radiation) of sites. According to the location of the consumption points, some constraints and decision rules have to be defined and taken into account in the optimization method. As example, data collected in rural communities from Niger Republic (West Africa) are used in this study.

This paper presents the different approaches of a Hybrid Renewable Energy System (HRES) injection power management. The HRES is connected to the Grid and to the Consumer by using a three-phase system. The two main operation states of the HRES are the Grid connected and OffGrid modes. Two different systems of control and management of the three-phase inverter of the HRES are needed. This inverter is responsible for power exchange between interior part of the HRES, as the PV production and the Storage system, and the external part, as the Three-phase system of HRES and the Consumer. The work describes the method of voltage control in the Off-grid mode, and the current control in the Grid connected mode with voltage synchronization with practical validation.

This paper mainly includes the preparation, characterization and thermal properties of Stearic Acid/Olive Pomace Powder (SA/OPP) and Stearic Acid/Olive Pomace Powder/Graphite (AS/OPP) as a new form-stable composite phase change material for thermal energy storage, which are prepared by impregnation method followed by uniaxial compression. The graphite is added to improve thermal conductivity of SA/OPP form-stable composite PCM. Environmental Scanning Electron Microscope (ESEM), Fourier Transform Infrared (FT-IR), Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis and Hot Disk Analyzer measurements are using to characterized morphology, chemical structure, thermal performances, thermal stability and thermal conductivity of form-stable composite PCMs, respectively. The DSC analysis reveals that the melting and freezing temperatures and the latent heats of the SA/OPP form-stable composite PCM are measured as 55 °C and 51 °C, 111 J/g and 109 J/g, respectively. In addition, thermal conductivity of the form-stable composite PCM is increased by adding 7 wt % of graphite.

This study is focused on the preparation and characterization of thermal properties and thermal reliability of Paraffin (Pa)/Red Brick (Br) composite as form-stable phase change material (PCM). The maximum mass fraction of Pa retained in Br was found as 40 wt% without the leakage of Pa, in melted state even when it's heated over the melting point of Pa. The materials used, red brick powder (Br), paraffin (Pa), expanded graphite (EG) and PCM composite are characterized by Laser Particle Size, by Environmental Scanning Electron Microscopy and Spectroscopy Infrared Fourier Transform. The thermo-physical properties of composites MCPs are studied by Differential Scanning Calorimetry. The results show that the composite to form stabilized prevents leakage of the phase change material from the matrix. The surface of the clay matrix is fully charged paraffin by a physical attraction. The FT-IR analysis shows that there is no chemical reaction between the matrix and the MCP. From differential scanning calorimetry (DSC) analysis, the melting and freezing temperatures and latent heats of the form-stable PCM were measured as 52.73 °C and 55.8 °C and 41.32 J/g and 42.39 J/g. Thermal conductivity of form-stable Pa/Br/EG (10%) composite (0.52 Wm−1K−1) was found to be 3 times higher than that of pure Pa (0.1716 Wm−1K−1). Based on all results, it was concluded that the form-stable Pa/EG (40/60 w/w%) has considerable latent heat energy storage potential because of its good thermal properties, thermal and chemical reliability and thermal conductivity.

In general cases, particularly in developing countries, the weakness of the national electric grid is due to overloading, high temperatures and bad weather. In such systems, the interruptions of electricity supply can take several hours to days. To prevent the power deficit, consumers can use diesel generators that are very noisy and highly polluting. But, as alternative, this paper proposes a combination of wind generator, PV and storage devices for load shifting. This can help to improve the grid resilience and the supply continuity. This paper presents a methodological analysis of the grid weakness, based on experimental data. The Expected Energy Not Supplied (EENS) is estimated and a multi-objective optimization method is applied for the system sizing. The main objective of this study is to develop strategy of renewable sources and storage sizing for resilience improvement of a weak grid. Costs of penalties are integrated to the fitness function that minimizes the cycle cost, and the results are presented and analyzed.

This paper presents a study of a building heating and comfort based on solar thermal system consisting of a solar thermal collector, a water storage tank, a boiler and a low temperature radiator. The formalism of Bond Graph is used for modeling of the solar water heater using a thermostat regulated hot water radiator for heating a building. The model is simulated through Matlab/Simulink software and its performance is analyzed.

This paper studies a Hybrid Renewable Energy System (HRES) as a reliable source of the power supply in the case of the connection to the grid. The grid connection imposes restrictions to the power delivered and harmonic content on the HRES. This causes the HRES to use multiple control systems and subsystems, as the normalization of the measurements, the current control, active harmonic compensation, synchronization, etc., described in this paper. Particular attention was paid to interactions in the storage system of the HRES. The durability of the HRES can be increased by the combination of the supercapacitors and batteries. This requires a power management solution for controlling the energy storage system. The aim of the supercapacitors is to absorb/inject the high-frequency fluctuations of the power and to smooth out the power of the batteries system of the HRES. This can be possible owing to the use of a low-pass second order filter, explained in this paper, which separates the high-frequency component of the storage system reference for the supercapacitor from the low-frequency component for the batteries system. This solution greatly increases the reliability and durability of the HRES.

International audience; This article is presented in the framework of the increasing interest for the use of latent heat transfer slurries for cooling processes. Paraffin serves as a latent heat storage material, and a polymer network acts as the supporting material. The phase change material melts around 7°C with a latent heat of fusion of 115 kJ/kg. Differential scanning calorimetry and indentation analysis were employed to investigate the thermal properties and mechanical stability of the material under freezing–thawing cycles. Results indicated that the form-stable phase change material with the advantages of no liquid leakage constitutes a potential material in the field of low-temperature thermal energy storage. Experimental investigation is made to study the melting process of a single slurry in an agitated bath. Analysis of data permits the development of a phenomenological correlation adapted to the millimetric dimension of the particle, leading to an estimation of the melting phase change time duration as a function of the main parameters of the problem.

To meet the needs always more accurate and demanding in the construction industry, mechanical and thermal or acoustic features of building materials have known significant improvements over the last two decades. Researchers in materials science and civil engineering are constantly listening to the industry and continue to innovate in this field. The current trend is the search for new materials, called intelligent, where several properties as mechanical and physico-chemical are combined. In our case, the aim was to develop a new construction material reaching the construction standards, --- i.e. with acceptable mechanical properties --- but which is also able to perform other functions such as thermal insulation or sound insulation. To do this, we chose to strengthen a cement mortar with natural fibers obtained from poultry feather. A physical and chemical stability behavior is obtained thanks to a treatment performed before their incorporation into the composite matrix. The fibers are introduced in a mortar matrix as a substitute for mineral or synthetic fibers which are traditionally used for this purpose. The cylindrical and prismatic specimens were then prepared with the composite in order to determine the mechanical characteristics of this composite. Compression tests and three-point bending were carried out for this purpose. To determine the thermal conductivity of composites, several plates with different percentages of fiber, whose size is 300x300x10 mm3, was chosen in order to be adaptable to the experimental device, were fabricated.

This paper deals with the battery energy management for the case of isolated locations when they are equipped by wind turbines using energy storage devices. To cover the shortfall or the overflow of those kind of generation caused suddenly by the wind variation, the energy storage device is a necessity to improve our isolated wind farm. From this condition a great part of the energy distribution is managed at the DC form the batteries. Those later are linked via DC-DC converters. The main idea of this paper is focused on DC-Bus voltage and currents control based on the fractional order PID. So a fractional order and integer order PID are applied. Their performance in the case of DC/DC converter for batteries discharging. PID controller is used to enhance output characteristics of the converter and a fractional order controller is proposed to achieve best performance to maintain stability of the dc link. The proposed control has been investigated through Matlab/Simulink environment.

This paper deals the study of the lead-acid behavior and its modelling based on the Kinetic Battery Model. Results of experimental tests are used to realize the analysis and to estimate the model parameters. These last can serve for prediction and estimation of the battery lifetime according to the actual operating conditions.

We present an analytical general solution of the well-known heat conduction problem in a one-dimensional homogeneous slab by using an expansion of the only delayed part of the temperature field function on an infinite eigen functions set. We propose to split the searched solution of the general problem in an instantaneous part and a delayed one which, with whatever boundary conditions combination, verifies Dirichlet conditions and then avoids the Gibbs problem. A space sampling and a reduction of the eigen basis produce a useful and usable numerical model which may be as accurate as required. The results we present may be used directly to numerically calculate solutions to a given problem and may be reused as a basis for more complex problems as multilayer walls or whole thermal systems studies.

The objective was to evaluate the viral infection effects on infertility treatment outcome in HIV-1 or hepatitis C (HCV) monoinfected infertile serodiscordant couples, in a retrospective case-controlled, university-based study. Clinical pregnancy rate for HIV-1 or HCV infertile serodiscordant couples was not significantly different from that for seronegative controls.

Objective To evaluate the pertinence of kinetic observations of embryonic development 25 hours after IVF, with a view to optimizing the choice of embryos for transfer. Design Retrospective study of 471 cycles with embryo transfer. Setting University Hospital. Intervention(s) Observations of changes in zygotes, in the 25th hour after insemination (25 h PI). Main Outcome Measure(s) Identification of three stages of development: two cells (2C), loss of the pronuclei (in syngamy; 0PN) and persistence of the two pronuclei (2PN). Embryonic morphology at 48 hours, according to the stages identified at 25 hours, was correlated with the rates of implantation and clinical pregnancy. Result(s) Two thousand four hundred seventy-eight day-2 embryos were observed. The number of blastomeres on day 2 differed significantly according to stage of development at 25 hours (2C: 69.8% vs. 0PN: 55% and 2PN: 24.6%). Implantation rates were significantly lower for cycles in which only 2PN embryos were produced (7%, n=160) than for cycles with at least one 2C embryo and/or, preferably, a 0PN embryo (14.4%). The implantation rate was significantly lower for the transfer of only 2PN embryos (7.6%) than for the transfer of only embryos that had advanced further by 25 h PI (15.2%). If only one type of embryo was transferred (2PN vs. 2C or 0PN), for embryos with a similar morphology at 48 hours, four-blastomere embryos derived from 2PN embryos implanted less efficiently than those derived from 2C and/or 0PN embryos. Conclusion(s) Observation at 25 h PI is a simple, rapid, and cheap method for identifying the best embryos to transfer. A lack of zygote development at 25 hours is associated with a poor prognosis, unless the zygote concerned has two to three cells on day 2. The development of zygotes with 2PN at 25 h PI should be taken into account as a function of their development at 48 hours.

In this paper, the Rainflow Cycles Counting Method is applied to estimate the supercapacitors lifetime. Several studies can be found in the literature but in most of them, estimation methods of supercapacitors lifetime are based only on the Ac-Impedance Spectroscopy Method or on the Cyclic voltammetry. The using of these methods is very fastidious and need a very high number of experimental cycling tests. Sometimes, it can be interesting to have a simplest but accurate method to estimate the life cycles of the supercapacitor. So, abacus can be realized by manufacturer to guide users or to be used in the Supercapacitor Energy Management System (SEMS) simulations. In this paper, a strategy, based on the Rainflow Cycle Counting Method, is established from long term experimental tests. This can facilitate an online estimation of the supercapacitor lifetime and storage energy management.

This paper presents the principal methods available for phase change material (PCM) implementation in different storage applications. The first part is devoted to a non-exhaustive overview of the various chemical processes used to develop stable PCM (such as microencapsulation, emulsion polymerization or suspension polycondensation, polyaddition, etc.) based on the available literature. The second part deals with shape-stabilized PCM, developed from an intimate combination of a polymer matrix and a phase change element. Materials able to include more thermal energy as usual ones are interesting as they increase the thermal inertia of the system that presents by this way advantages. The energy efficiency of buildings may be improved including PCMs that store and provide enthalpy from one hand and without any significant temperature modification during the phase change process on the other hand. If the solid phase of the PCM does not present any problem, it is not the same for the liquid phase which must be maintained mechanically at its assigned location. Furthermore, the PCM in the solid (and furthermore in the liquid phase) does not have mechanical properties which allow to use it as a structural material able to support charge loads. This paper presents different methods to distribute and maintain the PCM in the thermal solid matrix.

We propose a new inverse method which consists of building an “inverse model.” The model synthesis [1], which allows us to gather several coupled elementary models in a single one, can be used to permute some outputs with some inputs of the direct model, solving a special coupling between the direct model and a particular one called “inversor.” The model synthesis then provides an inverse model which can be used to perform usual simulations. We show the principles of the method, the practical “ticks,” and demonstrate with an example that it is an easy-to-use and efficient method.

In the case of collective buildings, heat fluxes between adjacent units are generally not taken into account and induce an over- or an under-estimation of every unitary heating or cooling demand. We show that the heat fluxes between adjacent units can be considered as unknown solicitations and then estimated with inverse methods. We propose a definition of an individual reference consumption. In order to be usable in practice, the whole proposed methodology verifies the confidentiality of measured data concerning every unit. The direct model used in the inversion process is a state model that describes all the heat transfer in the units; it is obtained by using a usual spatial discretisation method. It is assumed that the required experimental measurements for indoor temperature, heating power and for all climatic solicitations applied to the units are available. We illustrate the methodology with a unit controlled at a particular set point temperature and bordered by neighbour units controlled at different set points temperature (three cases are studied). The obtained results are commented and show that the seasonal energy stolen can be a high percentage of the whole energy demand of a unit.

In this paper, wind generator and photovoltaic systems are associated to the diesel generator to supply energy to the DC-bus. The maximum power point tracking methods are applied to the wind generator and photovoltaic systems to increase the renewable energy contributions and to reduce the fuel consumption. Interactions between sources are studied, and the storage device characteristics are analyzed in aims to make a choice of the appropriate storage technologies. The interest of combining the ultracapacitors with the battery, as storage devices, is prospected, and the number of cycles is estimated by using the rainflow counting method. The experimental tests bench is designed in a reduced scale, and some simulations and experimental results are presented and analyzed.