Muscular tissue regeneration may be enhanced in vitro by means of mechanical stimulation, inducing cellular alignment and the growth of functional fibers. In this work, a novel bioreactor is designed for the radial stimulation of porcine-derived diaphragmatic scaffolds aiming at the development of clinically relevant tissue patches. A Finite Element (FE) model of the bioreactor membrane is developed, considering two different methods for gripping muscular tissue patch during the stimulation, i.e., suturing and clamping with pliers. Tensile tests are carried out on fresh and decellularized samples of porcine diaphragmatic tissue, and a fiber-reinforced hyperelastic constitutive model is assumed to describe the mechanical behavior of tissue patches. Numerical analyses are carried out by applying pressure to the bioreactor membrane and evaluating tissue strain during the stimulation phase. The bioreactor designed in this work allows one to mechanically stimulate tissue patches in a radial... [more]

The output generations of renewable energy sources (RES) depend basically on climatic conditions, which are the main reason for their uncertain nature. As a result, the performance and security of distribution systems can be significantly worsened with high RES penetration. To address these issues, an analytical study was carried out by considering different penetration strategies for RES in the radial distribution system. Moreover, a bi-stage procedure was proposed for optimal planning of RES penetration. The first stage was concerned with calculating the optimal RES locations and sites. This stage aimed to minimize the voltage variations in the distribution system. In turn, the second stage was concerned with obtaining the optimal setting of the voltage control devices to improve the voltage profile. The multi-objective cat swarm optimization (MO-CSO) algorithm was proposed to solve the bi-stages optimization problems for enhancing the distribution system performance. Furthermore, th... [more]

Climate changes will have a huge impact on society, one that cannot be truly predicted. However, what is known is that our dependence on fossil feedstock for energy, fuel and chemical production will need to shift towards more biobased and circular feedstock. This paper describes part of an important technology development that uses biogenic and plastic-containing waste streams for the co-production of aromatics with fuels and/or chemicals. This paper captures the first decade of this technology development from idea towards a large Process Demonstration Unit operated and validated within a large gasification R&D infrastructure. The scale-up was successful, with supporting tools to optimize and identify the limits of the technology. Benzene and toluene are directly removed from the product gas with 97% and 99% efficiency, respectively. The next steps will be to include this development in larger piloting and demonstrations for the co-production of aromatics from biomass gasification (b... [more]

In the context of wave resource assessment, the description of wave climate is usually confined to significant wave height and energy period. However, the accurate joint description of both linear and directional wave energy characteristics is essential for the proper and detailed optimization of wave energy converters. In this work, the joint probabilistic description of wave energy flux and wave direction is performed and evaluated. Parametric univariate models are implemented for the description of wave energy flux and wave direction. For wave energy flux, conventional, and mixture distributions are examined while for wave direction proven and efficient finite mixtures of von Mises distributions are used. The bivariate modelling is based on the implementation of the Johnson−Wehrly model. The examined models are applied on long-term measured wave data at three offshore locations in Greece and hindcast numerical wave model data at three locations in the western Mediterranean, the Nort... [more]

The rise of personalised and highly complex drug product profiles necessitates significant advancements in pharmaceutical manufacturing and distribution. Efforts to develop more agile, responsive, and reproducible manufacturing processes are being combined with the application of digital tools for seamless communication between process units, plants, and distribution nodes. In this paper, we discuss how novel therapeutics of high-specificity and sensitive nature are reshaping well-established paradigms in the pharmaceutical industry. We present an overview of recent research directions in pharmaceutical manufacturing and supply chain design and operations. We discuss topical challenges and opportunities related to small molecules and biologics, dividing the latter into patient- and non-specific. Lastly, we present the role of process systems engineering in generating decision-making tools to assist manufacturing and distribution strategies in the pharmaceutical sector and ultimately em... [more]

Ethyl ester production from palm fatty acid distillate (PFAD) with ethanol in the presence of sulfuric acid and potassium hydroxide was performed in a continuous three-step process using the ultrasound clamps and an ultrasonic probe. The ultimate goal was to produce biodiesel from the PFAD. In the first and second esterification steps, 16 units of a 400 W ultrasound clamp (20 kHz) were attached 100-m apart along each tubular reactor. In the third transesterification step, a 1000-W ultrasonic homogenizer (18 kHz) was used in a 100-mL continuous reactor. A composite central design of experiments and the response surface methodology (RSM) were used to develop predictive models and identify the optimal conditions of each step based on the purities of ethyl ester. The optimal conditions in the first step were 46.1 vol.% ethanol, 1.4 vol.% sulfuric acid, and purity 66.68 wt.% ethyl ester. In the second step, the optimized conditions were 57 vol.% ethanol, and 2.1 vol.% sulfuric acid, purity... [more]

In recent years, liposomes have gained increasing attention for their potential applications as drug delivery systems in the pharmaceutic, cosmetic and food industries. However, they have a tendency to aggregate and are sensitive to degradation caused by several factors, which may limit their effectiveness. A promising approach to improve liposomal stability is to modify liposomal surfaces by forming polymeric layers. Among natural polymers, chitosan has received great interest due to its biocompatibility and biodegradability. This review discussed the characteristics of this combined system, called chitosomes, in comparison to those of conventional liposomes. The coating of liposomes with chitosan or its derivatives improved liposome stability, provided sustained drug release and increased drug penetration across mucus layers. The mechanisms behind these results are highlighted in this paper. Alternative assembly of polyelectrolytes using alginate, sodium hyaluronate, or pectin with c... [more]

Biodiesel is one the most sought after alternate fuels in the current global need for sustainable and renewable energy sources due to their lower emissions and no major modification requirement to existing engines. However, the performance and productivity of the biodiesel production process are significantly dependent on the process parameters. In this regard, a novel hybrid genetic programming-gray wolf optimizer approach for the process optimization of biodiesel production is proposed in this paper. For an illustration of the proposed approach, kinematic viscosity is expressed as a symbolic regression metamodel to account for the influence of catalyst concentration, reaction temperature, alcohol-to-oil molar ratio, and reaction time. Then, the genetic programming-based symbolic regression metamodel is used as an objective function by the gray wolf optimizer to optimize the process parameters. The obtained results show that the proposed approach is simple, accurate, and robust.

In this study, a targeted oxygen-enrichment technology was proposed to enhance coal combustion in an ironmaking blast furnace. The coal flow and combustion characteristics under targeted oxygen-enrichment were investigated using the computational fluid dynamics (CFD) method. The results showed that oxygen utilization and coal burnout were significantly increased under targeted oxygen-enrichment. The coal burnout at 24% O2 concentration was 86.29%, which was the maximum and indicated an increase of 13.13%. However, the cooling effect of room-temperature oxygen had some adverse effects on coal combustion. Given this, the effect of coal particle temperature on coal combustion was investigated based on targeted oxygen-enrichment. The coal combustion process was further enhanced. The coal burnout at a 600 K particle temperature and 25% oxygen concentration was 91.12% and had an increase of 17.96%, which was the maximum.

The mixed collector can improve low rank coal flotation efficiency, but its synergistic mechanism needs to be further explored. In this paper, oleic acid-dodecane (OA-D), oleic acid (OA), and dodecane (D) were employed to treat the low rank coal for revealing new synergistic mechanism of the mixed collector. First the surface free energy of the coal, the surface free energy of coal-water and coal-water-coal were calculated. Then wetting heat measurement, X-ray Photoelectron Spectroscopy (XPS) and FTIR were used to analyze synergistic mechanism of the mixed collector in depth. The results showed that OA-D obtained a higher combustible recovery than using OA and D, respectively. The essence of synergetic mechanism of OA-D was that they formed a relatively ordered “supramolecular structure” on the low rank coal surface, especially there were hydrophobic and van der Waals forces between the oleic acid chain and the dodecane chain that can promote the formation of a continuous collector fil... [more]

The potential for utilizing industrial waste heat for district heating is enormous. There is, however, often a temporal mismatch between the waste heat availability and the heating demand, and typically fossil-based peak boilers are used to cover the remaining heat demand. This study investigates the potential of applying a thermal energy storage tank at the district heating supply system at Mo Industrial Park in Norway, where waste heat from the off-gas of a ferrosilicon production plant is the main heating source. To cover peak heating demands, boilers based on CO gas, electricity, and oil are applied. The reduction in peak heating costs and emissions is evaluated as a function of tank size for two different scenarios: (1) a scenario where CO gas, which is a byproduct from another nearby industry, is the main peak heating source; and (2) a scenario where no CO gas is available, and electricity is the main peak heating source. The highest economic viability is obtained with the smalle... [more]

This study examines the applicability of the ice storage systems in the small commercial refrigerated showcases through experimental analysis. R-404A is used as the working fluid and various influence of parameter settings and improvements, are discussed in details. In the ice storage system, the condenser is changed from air-cooling (refrigeration mode) to an immersion type that is placed in an ice storage tank, the corresponding condensing temperature and pressure are reduced appreciably. This increased the efficiency and can effectively reduce the peak power consumption. The reduction of the condensing temperature and pressure increased the coefficient of performance (COP) from 3.6 (refrigeration mode) to 6.35 (melting mode), effectively enhancing the refrigeration efficiency. The results indicated that the ice storage system could effectively increase the coefficient of performance from 3.6 to 6.35 during ice melting when compared to the conventional refrigeration system. It also c... [more]

Energy storage is a key solution to supply renewable electricity on demand and in particular batteries are becoming attractive for consumers who install PV panels. In order to minimize their electricity bill and keep the grid stable, batteries can combine applications. The daily match between PV supply and the electricity load profile is often considered as a determinant for the attractiveness of residential PV-coupled battery systems, however, the previous literature has so far mainly focused on the annual energy balance. In this paper, we analyze the techno-economic impact of adding a battery system to a new PV system that would otherwise be installed on its own, for different residential electricity load profiles in Geneva (Switzerland) and Austin (U.S.) using lithium-ion batteries performing various consumer applications, namely PV self-consumption, demand load-shifting, avoidance of PV curtailment, and demand peak shaving, individually and jointly. We employ clustering of the hous... [more]

The study examines the implications of educating prosumers regarding Internet of Things (IoT) use and monitoring to reduce power consumption in the home and encourage energy conservation, sustainable living, and behavior change. Over 15 months, 125 households and household owners received training regarding IoT plug equipment, usage monitoring, and energy reduction. A face to face survey was then conducted regarding power consumption reductions, frequency of monitoring, and user satisfaction compared to the previous year. The study found that participating households used around 5% less energy compared to average households. The reduction rate was found to have increased when more appliances were connected to smart plugs and their power usage was monitored more frequently. Power usage also fell in a greater level when participants were more satisfied with being given smart plugs and related education. Moreover, energy reduction rates increase when smart plugs were used for cooling and... [more]

Modern electrical grids are transitioning from a centralized generation architecture to an architecture with significant distributed, intermittent generation. This transition means that the formerly sharp distinction between energy producers (utility companies) and consumers (residences, businesses, etc.) are blurring: end-users both produce and consume energy, making energy management and public policy more complex. The goal of the Open Power Quality (OPQ) project is to design and implement a low cost, distributed power quality sensor network that provides useful new forms of information about modern electrical grids to producers, consumers, researchers, and policy makers. In 2019, we performed a pilot study involving the deployment of an OPQ sensor network at the University of Hawaii microgrid for three months. Results of the pilot study validate the ability of OPQ to collect accurate power quality data in a way that provides useful new insights into electrical grids.

In this work, the dynamic combustion characteristics in a scramjet engine were investigated using three diagnostic data analysis methods: DMD (Dynamic Mode Decomposition), STFT (Short-Time Fourier Transform), and CEMA (Chemical Explosive Mode Analysis). The data for the analyses were obtained through a 2D numerical experiment using a DDES (Delayed Detached Eddy Simulation) turbulence model, the UCSD (University of California at San Diego) hydrogen/oxygen chemical reaction mechanism, and high-resolution schemes. The STFT was able to detect that oscillations above 50 kHz identified as dominant in FFT results were not the dominant frequencies in a channel-type combustor. In the analysis using DMD, it was confirmed that the critical point that induced a complete change of mixing characteristics existed between an injection pressure of 0.75 MPa and 1.0 MPa. A combined diagnostic analysis that included a CEMA was performed to investigate the dynamic combustion characteristics. The difference... [more]

Vehicle platooning has been proposed as one of the potential technologies for intelligent transport systems to improve transportation and energy efficiency in urban cities. Despite extensive studies conducted on the platooning of heavy-duty trucks, literature on the analysis of urban vehicle platoons has been limited. To analyse the impact of platooning in urban environments, this paper studies the influence of intervehicle distance, platoon size and vehicle speed on the drag coefficient of the vehicles in a platoon using computational fluid dynamics (CFD). Two vehicle models—a minibus and a passenger car—are analysed to characterise the drag coefficients of the respective platoons. An analysis of energy consumption is conducted to evaluate the energy savings with platooning using a longitudinal dynamics simulation. The results showed a reduction in the average drag coefficient of the platoon of up to 24% at an intervehicle distance of 1 m depending on the number of vehicles in the pla... [more]

Prussian Blue analogues (PBAs) are a promising class of electrode active materials for batteries. Among them, copper nitroprusside, Cu[Fe(CN)5NO], has recently been investigated for its peculiar redox system, which also involves the nitrosyl ligand as a non-innocent ligand, in addition to the electroactivity of the metal sites, Cu and Fe. This paper studies the dynamics of the electrode, employing surface sensitive X-ray Photoelectron spectroscopy (XPS) and bulk sensitive X-ray absorption spectroscopy (XAS) techniques. XPS provided chemical information on the layers formed on electrode surfaces following the self-discharge process of the cathode material in the presence of the electrolyte. These layers consist mainly of electrolyte degradation products, such as LiF, LixPOyFz and LixPFy. Moreover, as evidenced by XAS and XPS, reduction at both metal sites takes place in the bulk and in the surface of the material, clearly evidencing that a self-discharge process is occurring. We observe... [more]

This paper presents a series of economic efficiency studies comparing three different investment variants: without energy storage, with energy stored in batteries and hydrogen installation with a PEM fuel cell stack for a location in Poland. To reach a target, the current solar potential in Poland, the photovoltaic (PV) productivity, the capacity of the energy storage in batteries as well as the size of the hydrogen production system were calculated. The solar potential was determined using archival meteorological data and the Krieg estimation method. A laboratory scale PV system (1 kW) was used to estimate the decrease in real solar installation power during the last 10 years of operation. All analyses were made for a 100 kW photovoltaic array located in Poland using static and dynamic methods of investment project assessment, such as Simply Bay Back Period (SPBP) or Net Present Value (NPV). The results showed that the SPBP amounted to 8.8 years and NPV 54,896 € for non-storage system... [more]

The valorization of residual biomass plays today a decisive role in the concept of “circular economy”, according to which each waste material must be reused to its maximum extent. The collection and energy valorization at the local level of biomass from forest management practices and wildfire prevention cutting can be settled in protected areas to contribute to local decarbonization, by removing power generation from fossil fuels. Despite the evident advantages of bioenergy systems, several problems still hinder their diffusion, such as the need to assure their reliability by extending the operating range with materials of different origin. The Italian project “INNOVARE—Innovative plants for distributed poly-generation by residual biomass”, funded by the Italian Ministry of Economic Development (MISE), has the main scope of improving micro-cogeneration technologies fueled by biomass. A micro-combined heat and power (mCHP) unit was chosen as a case study to discuss pros and cons of bio... [more]

This paper proposes a novel multifunctional isolated microinverter which is able to extract the maximum available power from a solar photovoltaic module and inject it into the power grid, while simultaneously charging a battery energy storage system (BESS). The proposed microinverter integrates a novel DC−DC power converter and a conventional DC−AC power converter. The DC−DC power converter is able to send electrical energy to the secondary side of a high-frequency transformer and to the BESS, using only two power switches. Throughout this paper, the converter topology, the operation modes, the control algorithms, and the development of a laboratory prototype of the proposed microinverter are described in detail. Moreover, simulation and experimental results are presented to demonstrate the feasibility of the proposed solution.

This study aims to provide a thermodynamic comparison between supercritical CO2 cycles and ORC cycles utilizing flue gases as waste heat source. Moreover, the possibility of using CO2 mixtures as working fluids in transcritical cycles to enhance the performance of the thermodynamic cycle is explored. ORCs operating with pure working fluids show higher cyclic thermal and total efficiencies compared to supercritical CO2 cycles; thus, they represent a better option for high-temperature waste heat recovery provided that the thermal stability at a higher temperature has been assessed. Based on the improved global thermodynamic performance and good thermal stability of R134a, CO2-R134a is investigated as an illustrative, promising working fluid mixture for transcritical power cycles. The results show that a total efficiency of 0.1476 is obtained for the CO2-R134a mixture (0.3 mole fraction of R134a) at a maximum cycle pressure of 200 bars, which is 15.86% higher than the supercritical carbon... [more]

The complexity of modern hybrid powertrains poses new challenges for the optimal control concerning, on one hand, the thermal engine to maximize its efficiency, and, on the other hand, the vehicle to minimize the noxious emissions and CO2. In this context, the engine calibration has to be conducted by considering simultaneously the powertrain management, the vehicle characteristics, and the driving mission. In this work, a calibration methodology for a two-stage boosted ultra-lean pre-chamber spark ignition (SI) engine is proposed, aiming at minimizing its CO2 and pollutant emissions. The engine features a flexible variable valve timing (VVT) control of the valves and an E-compressor, coupled in series to a turbocharger, to guarantee an adequate boost level needed for ultra-lean operation. The engine is simulated in a refined 1D model. A simplified methodology, based on a network of proportional integral derivative (PID) controllers, is presented for the calibration over the whole oper... [more]

The HVAC system represents the main auxiliary load in electric vehicles, but passengers’ thermal comfort expectations are always increasing. Hence, a compromise is needed between energy consumption and thermal comfort. The present paper proposes a real-time thermal comfort management strategy that adapts the thermal comfort according to the energy available for operating the HVAC system. The thermal comfort is evaluated thanks to the “Predicted Mean Vote”, representative of passenger’s thermal sensations. Based on traffic and weather predictions for a given trip, the algorithm first estimates the energy required for the traction and the energy available for thermal comfort. Then, it determines the best thermal comfort that can be provided in these energetic conditions and controls the HVAC system accordingly. The algorithm is tested for a wide variety of meteorological and traffic scenarios. Results show that the energy estimators have a good accuracy. The absolute relative error is ab... [more]

Designing eco-friendly products involves energy efficiency improvements. Eco-friendly products must consider not only raw materials and manufacturing processes to improve energy efficiency but also energy needed when designing them. This research shows how eco-routing (ER), eco-charging (EC), eco-driving (EDR), vehicle-to-grid (V2G) and electric vehicles (EVs) can contribute to the reduction of energy consumption during product design. To do this, a group of 44 engineers assigned to the project was chosen to assess the total energy available for V2G when driving EVs from their homes to the design center by using ER, ED and EC by running an application coded by the authors. The energy stored in EVs was used to quantify the reduction in energy consumption of the buildings present in the design center. The results show that the energy saving ranges from 2.89% to 6.9% per day—in other words, 93 kWh per day during the design process. In addition, the fact of making the design process greene... [more]