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[Display omitted] • Difference in working principle of Solar Thermoelectric Generators (STEGs) and PV-TEG Hybrid Generators is discussed. • Design parameter optimization of TEG only system is not same as that for STEG and PV-TEG hybrid system. • Enhancement in the concentration ratio improves TEGs efficiency, leading to increased conversion efficiency of the hybrid system. • Micro-channel heat pipe significantly reduces the number of TEG used, thus, reducing the overall cost of the system. With the continuously increasing demand for energy, reduction in greenhouse gas emission for daily energy usage is a challenging task. Solar energy based technologies possess the potential to address this challenge since sun is a renewable and abundant source that does not produce any emissions. It would be additional benefit if in the process of using such technologies, wasted heat energy is also converted into electrical energy. Thus, integration of thermoelectric and photovoltaic hybrid systems offers the flexibility to exploit solar spectrum across full wavelength. Thermoelectric Generator (TEG) when integrated with solar electricity conversion technologies result in fabrication of (i) solar thermoelectric generators (STEGs) and (ii) photovoltaic-thermoelectric (PV-TEG) hybrid devices with enhanced efficiency. Improvements in the conversion efficiencies of these technologies would aid in making solar energy at par with conventional forms of energy generation. This paper reviews the prospect of integrating TEG with solar electricity conversion technologies by examining the recent efforts in the field. In particular, the difference in the working of these two type of devices have been focussed on. This review presents in-depth analysis of the state-of-the-art methods used to achieve optimum performance. Moreover, various applications are stated and PV efficiency and losses are discussed along with possible resolutions. Furthermore, recent advancements in these device technologies have been compiled and cost and commercialization aspects have been focussed on. The review aids as a guide to select appropriate procedure of optimizing the performance in these devices as per requirements and specific application. [ABSTRACT FROM AUTHOR]

According to scientific studies dealing with the statistics of ICE (internal combustion engine) failures, most of them are registered in the ignition system (25%) and the power system (35%). The operable state of the ICE fuel system can be maintained by developing effective testing methods. For the purpose of theoretical research, a DBD-4 testing device was designed in the methodological part of the research. The use of the developed methodologies and instrumentation allowed carrying out experimental studies to diagnose the operability of the fuel supply system. Analyzing the obtained experimental data, it can be affirmed that: there is a stable relationship between the change in the ICE crankshaft speed and the change in the injection duration of the electromagnetic injector; the degree of wear of the electric fuel pump (EFP) is determined by the shift of the stable value of the crankshaft speed to the zone of low speed values at the same injection durations. The data obtained after testing the EFP allows planning a further algorithm of actions to maintain the operability of the fuel supply system. [ABSTRACT FROM AUTHOR]

• The study investigates shipboard power systems and distortion evaluation in "EXPERT 3." • The study analyzes distortions in converter-based propulsion systems with variable-frequency drives. • The study confirms MATLAB model accuracy at ship synchronous generators. • The paper introduces a resonance-based compensating device, validated experimentally. • The research investigates methods for managing high-frequency disturbances. This research addresses electromagnetic compatibility and power quality (EMC and PQ) challenges in shipboard electric power systems (SEPS) with dynamic positioning (DP) capabilities, focusing on the self-propelled floating crane (SPFC) "EXPERT 3." Our goal is to enhance methodologies for evaluating power quality indicators (PQI) related to voltage and current waveform distortions, specifically in converter-based propulsion complexes (CBPCs) featuring variable-frequency regulated asynchronous drives (VFDs). We investigate harmonic current and voltage distortions, reactive power generation, and power factor (PF) in SEPS "EXPERT 3″ during the operation of VFDs with conventional semiconductor power converters (SPCs). A refined MATLAB model considers equipment and cable network parameters, validating distortion indicators at ship synchronous generators (SGs). PQI compliance with international maritime standards is verified at the point of common coupling (PCC) for various VFD configurations with pulse width modulated (PWM) SPCs and filter-compensating devices (FCDs). We propose an improved controlled FCD (CFCD) incorporating a resonance filter (RF) and a controllable reactor compensator (CRC). CFCD efficiency in various VFD configurations is experimentally validated. We analyze harmonic distortions of voltage and current, including high-frequency (HF) commutations in VFDs with input thyristor-based rectifiers (TBRs), considering parasitic "phase-hull" capacitances of cable line segments (CLS). Our study examines harmonics in CBPC-based SEPS in two sub-frequency ranges: low-frequency (LF) − 0 to 2 kHz and high-frequency (HF) − 2 kHz to 500 kHz.© 2017 Elsevier Inc. All rights reserved. [ABSTRACT FROM AUTHOR]

Ethiopia's cattle population is among the largest in Africa and is burdened by frequent foot-and-mouth disease (FMD) outbreaks. FMD is caused by several distinct and highly contagious viral strains that can result in acute disease in cattle, causing losses in productivity and impeding international trade. This economic simulation study considered four main sources of losses due to FMD in cattle: reduced milk yield, draft power yield, fertility, and increased mortality. Economic losses were estimated per case across age-sex strata in 89 Ethiopian administrative zones for the years 2010–2021 using a wide range of data to estimate distributions for 30 input variables in a series of Monte Carlo simulations. It was estimated that an average case of FMD in Ethiopian cattle results in losses (mean values reported followed 95 % confidence intervals in brackets) of US dollars (USD) 11 (USD 7–USD 16) per case. Losses resulting from an average outbreak were estimated to be USD 2300 (USD 1400–USD 3300), while national annual losses were estimated to be USD 0.9 Mil. (USD 0.2 Mil.–USD 2.3 Mil.). Per cow-year, based on a national cow population of approximately 39 Mil. head, these estimated annual losses are equivalent to losses of only USD 0.02 (USD 0.01–USD 0.06). Nationally, these losses were significantly less than previously estimated in the literature, with currently estimated losses more accurately reflecting the economic burden of FMD in Ethiopian cattle over the past decade. The relatively small estimated losses suggest that control efforts based on widespread vaccination in countries with primarily extensive cattle production systems, such as Ethiopia, are unlikely to be economically sound. Sensitivity analyses suggested losses would be far greater in intensive systems, and that certainty surrounding incidence rates is paramount to the formulation of economically sound animal healthpolicy in regions with endemic FMD. [ABSTRACT FROM AUTHOR]

Pakistan's power distribution utilities (DISCOs) face significant challenges, including outdated infrastructure, theft, and financial constraints, leading to inefficiencies and higher costs. A new framework proposes a strategy for operational enhancement and sector reforms, focusing on modernizing management, increasing capacity, improving network reliability, and implementing advanced metering and automated solutions. It aims to bolster transactional accuracy, safety, and inventory management, recalibrate subsidies, and ensure rigorous IT oversight for loss reduction and maintenance optimization. The framework promotes sustained investment and professional development, striving for financial stability and accountability while empowering DISCOs with the autonomy to maintain efficiency and engage consumers more effectively. [Display omitted] • A framework prioritizes modernization, bolstering capacity, and improving network reliability. • Efforts include automated solutions, advanced metering, and integrated billing for operational refinement. • Pushes for subsidy recalibration, sector planning, and IT oversight to strengthen infrastructure. • Emphasizes continual growth, reducing losses, and maintaining reform momentum. • Seeks to empower DISCOs while enforcing accountability through incentives and surveillance. [ABSTRACT FROM AUTHOR]

The thermal behavior of perovskite solar cells (PSCs) can significantly affect their performance, and its investigation leads to a deep understanding of PSCs optimization. In this paper, the electrical and thermal behavior of a PSC is studied. To this end, the optical generation rate is calculated for the standard AM 1.5 solar spectrum and then is applied to calculate the current-voltage characteristics. Examining the efficiency (considering the recombination) for different materials of the electron and hole transfer layers (ETM, HTM, respectively), a structure with better merits is selected. The results revealed that Spiro-OMeTAD as the HTM layer leads to better results than the inorganic one. Hence, the Spiro-OMeTAD-based PSC structures were selected for the thermal modeling section. In the final step, considering the heat generated due to losses (resulting from resistive heating and non-radiative recombination), the thermal behavior of devices is surveyed. The structures with geometrical dimensions of a practical PSC (deposited on a glass substrate with a SiO 2 passivation layer) show operating temperatures between 73 °C to 76°C and 80°C to 84.5°C for ZnO and TiO 2 as ETMs, respectively. The high heat generated in the perovskite layer can accelerate its undesirable chemical reactions. Surveying the temperature distribution of PSCs can pave the way to study its effects on ion migration and the corrosion of contacts, which are the main drawbacks of such low-cost energy harvesters. [ABSTRACT FROM AUTHOR]

The paper describes the properties of glycerol produced by transesterification, especially the ester content in the glycerol phase (ester losses) including the distribution of esters according to higher fatty acids. Glycerol, produced by transesterification of oil as a side product – the polar glycerol phase, is an important chemical raw material. The decreasing of ester losses is important because it (i) increases the ester yield and especially (ii) decreases the cost of glycerol purification. The transesterification of oils (rapeseed, olive, palm, sunflower and Camelina Sativa) with various distributions of fatty acids was carried out by methanol, ethanol and butanol including different transesterification stopping. The losses of ethyl and butyl esters are much higher than losses of methyl ester (approximately 2–3x). The distribution of ethyl and butyl esters in the glycerol phase is the same as in the ester phase, whereas distribution of methyl ester is different and depends on the way of transesterification stopping. The reason is the different polarity of methyl esters, which depends on the type of fatty acid. The polarity increases with increasing of double bonds, i.e. the most soluble is methyl ester of linolenic acid in the glycerol phase. [Display omitted] [ABSTRACT FROM AUTHOR]

To further improve the efficiency of the wafer-based silicon photovoltaic (PV) module, producers are introducing new module designs with cut-cells. Since smaller solar cells might be affected by partial shading even more and earlier than full-size cells, the energy performance simulations of partially shaded modules are crucial. A detailed shading analyses of partially shaded modules with different cut cell designs are presented not only on a single case scenario but on annual energy yield simulations using Spice, where a shading scenario over the whole module by the use of a new 3D shading horizon profile of selected shading objects is calculated. The annual simulations reveal that regardless the module design almost all cells in the module are confronted by reverse bias, which can deteriorate the module performance significantly. Simulation results with three different shading objects on five different module topologies at five locations showed that the best cut-cell module design depends strongly by the micro location and shading objects; however, in general the string of solar cells connected in series should be aligned with the shading shape around noontime as much as possible. A comprehensive annual energy performance evaluation of partially shaded cut-cell modules revealed; that with a correct cell layout of cut-cells in a PV module, the shading losses can be reduced by 30–50% if comparing to the standard PV module design. • Annual energy performance model of partially shaded modules. • Energy balance model for partially shaded modules. • Comprehensive electrical evaluation of the partially shaded module on the cell level. [ABSTRACT FROM AUTHOR]

• An intuitive methodology for assessment of shading losses in PV systems is proposed. • The methodology proposes tools for shadow prediction and power output estimation. • A study of different shadow pattern impact was performed. • The annual shading losses of a PV plant were evaluated. Frequently, PV systems are affected by dirt, dust or shadowing from surrounding elements, such as trees and buildings. The shadows can cause partial shading conditions, when the irradiance is not uniform on PV installation, which lead to losses of power. Thus, the shadow prediction is primordial for a better output power estimation and to minimize its losses. The aim of this article is to propose a methodology using intuitive and available tools for shading prediction and losses assessment on PV installations. A study about the shadow pattern and module orientation (portrait and landscape) influence and an analysis of the shading losses on a PV plant were performed in order to demonstrate the applicability of the methodology. The shading effect is drastic when the shading is parallel to the short edge, whereas the effect is lower when it is parallel to the long edge. On the other hand, the losses due to shading and the difference in the position of the modules (landscape or portrait) have a lower impact on the photovoltaic plant case. It was concluded that the methodology is feasible and applicable for shading impact evaluation, despite limitations for large systems due to the simulation time. [ABSTRACT FROM AUTHOR]

Performance of electric motors and losses in terms of heat and temperature are reviewed in this paper. Airgap eccentricity, electromagnetic performance, effect of temperature and losses are shown as factors affecting the efficiency. Several methods of computer aided analyses are listed. Temperature distribution in an induction motor is shown through the results of a simulation. Different cooling methods are reviewed. Future directions for research include cryogenic cooling, heat pipes and usage of phase change materials. [ABSTRACT FROM AUTHOR]

• Developed free-piston stirling cryocooler (FPSC) and tested for LNG (re)liquefaction. • Developed numerical model that reflects a damping effect on the displacer. • Explained dynamics of the piston and displacer using a phasor diagram. • Classified mechanical and thermal losses of the FPSC. This research paper discusses the free-piston Stirling cryocooler (FPSC) in conjunction with a dual-opposed linear compressor. The system was tested under various operational conditions. The developed compressor can produce mass flow with an efficiency exceeding 60%; a loss analysis was conducted with care. The dynamic and thermal aspects of the experimental results are extensively verified via the numerical model. The model describes the physical characteristics of the Stirling cryocooler when a damping effect is applied to the displacer. The damping effect incorporated in the model is expressed through a function of the expansion work at the cold-end. It was also confirmed that the damped motion of the displacer is more suitable than undamped motions for describing real situations. The relevant dynamic characteristics of the piston and the displacer are also explained through the introduction of a phasor diagram. The developed model explains the physics of the Stirling cryocooler well, while accurately explaining the quantity of losses (i.e. heat conduction, imperfection of regenerator and shuttle heat transfer) that are distributed at its cold-end. The thermal load is regulated at various cold-end temperatures of 110 K, 120 K, 150 K and 190 K, and the system is capable of exerting maximum Carnot efficiencies of 25%, 27%, 28% and 29%, respectively. [ABSTRACT FROM AUTHOR]

• First dynamic model of water-related energy for showering. • More than 85% of water heating is lost down the drain. • Reusing energy with a heat exchanger reduces losses by 41%. • "Super" insulation of hot-water pipes reduces losses from 5% to 4%. • Data of minutely monitored shower events. Shower systems, related hot-water systems and pipe losses dominate residential water-related energy. However, many time-based technological, behavioural and environmental factors influence water use and related energy consumption. This has meant that, to date, the performance of these systems has been relatively poorly understood. Here we build on earlier stationary modelling and analysis to develop and apply a Dynamic Water-Related Energy Material Flow Analysis Model in Households (DYNWAREHO). We use this to evaluate a highly monitored household to answer "What are the key energy pathways, their relative importance, and the key factors of influence, in household shower and hot-water supply systems? We explore how significantly hot-water losses can be influenced by showering behaviour and/or technological changes such as pipe insulation. We show that in the household studied, over 85% of the energy used for water heating flows as waste down the drain. Losses are the second largest energy user and account for more than 10% in the studied household. Energy use for actual "showering" accounts for less than 5% of the total. New technologies could influence this significantly. This result clarifies the significant wastage of energy inherent in the design and use of current shower systems. The analysis shows various options designed to improve design and management; it was made possible by the creation of the DYWAREHO model, applicable to any household, and calibrated on a specific Australian household. If acted upon through policy decisions and an appropriate design of shower and wastewater systems, the research can substantially improve the management of water-related energy. [ABSTRACT FROM AUTHOR]

Highlights • Six months of storage of Calabrian laricio pine wood chips were studied. • The influence of different covers (uncover, PP sheet, PVC sheet) was analyzed. • Chemical and physical properties of wood chips were monitored for all storage period. • Open-air uncovered storage is suitable for storage periods less than 2 months. • The smallest loss of energy content (26%) was registered by the pile under PP sheet. Abstract This study evaluated the influence of storage method on the physical and chemical properties of laricio pine wood chips for energy generation in the region of Basilicata, Italy. The storage of wood chips is a key factor in the wood fuel supply chain because it allows to compensate temporal differences between production and consumption stages. Experimental trials were performed analyzing three storage methods of wood chips: uncovered pile, under vapour-permeable and waterproof cover (PP sheet), and under waterproof PVC cover (PVC sheet). During six months of storage (from August 2016 to January 2017), only the wood chips pile covered under PP sheet registered a decrease in moisture content (about -19%). Use of cover made of vapour-permeable material was also found to improve the heating value of biomass (about +15%). However, the ash content was observed to increase throughout the storage period, reaching the maximum value for the uncovered wood chips pile (about +74%). No statistically significant differences between PP and PVC sheets were detected for dry matter losses, while significant energy losses were found in every kind of storage system. As a result of the analyzed weather conditions, open-air uncovered storage is suitable for short-term storage periods (less than 2 months), while for long-term period the use of permeable covers is more profitable. [ABSTRACT FROM AUTHOR]

Focusing on a high-pressure turbine, this study conducts a multi-objective optimization aimed to improve its aerodynamic and erosion resistance performances. With a self-adaptive updated Kriging model first applied, the Latin hypercube sampling method and NSGA-II algorithm are then used to find trade-off solutions. The sensitivity analysis shows that the efficiency is mainly influenced by the flow angles near trailing edges of three selected blade spans, among which the flow angle near the trailing edge of middle span is the most significant, followed by the root span and tip span, while the dominant design parameters affecting the erosion are the flow angles near trailing edges of middle span and tip span. After optimization, the erosion around the middle span on pressure side and middle chord on suction side is significantly reduced due to the decrease of impact velocity and impact frequency, and the increase of impact angle. Besides, the low-velocity fluid regions near the pressure side of middle span and the trialing edge of tip are greatly reduced, which can relieve the blockage of flow passage. At all axial sections considered, the optimized blade is shown to significantly reduce losses near the tip and suction side, especially at 80% axial section. • Aerodynamic and anti-erosion performances of a high-pressure turbine are optimized. • Trade-off solutions are found with Kriging model, LHS method and NSGA-II algorithm. • The most dominant design variables affecting efficiency and erosion are obtained. • Original and optimized blades are compared to reveal performance enhancement. [ABSTRACT FROM AUTHOR]

Highlights • Additional renewable energy and storage reduce the cost or rural electrification compared to pure grid extension. • The reliability of the central power grid and of the microgrid are introduced as important parameters. • Results on 20 test cases show that these parameters influence the choice of rural electrification strategy. • Local, renewable energy generation reduces drastically the grid losses: from 23.2% to 8.7% in the best scenario. Abstract Globally, 1.2 billion people have yet to be granted access to electricity. Another 2.4 billion receive an intermittent electrical supply due to undersized and unreliable rural power grids. However, existing rural electrification programs focus mostly on extending the central power grid, thus providing an intermittent supply and increasing the losses on the power grid. In the literature, extension of the central grid is unilaterally compared with a stand-alone microgrid solution. In the model for rural electrification presented in this paper, the extension of the central grid is supplemented with local renewable energy generation and storage. The “reliability of the central power grid”, the “expected reliability of electrical supply in the village”, and the “losses” are also introduced as important design parameters. The usefulness and relevance of the proposed model was illustrated through 20 test cases. For Kanjikuzhi, an Indian village, additional renewable energy can reduce the average cost of electricity by 26%, diminish power interruptions by 40% and decrease grid losses by 62.5%, compared to a simple extension of the central power grid. [ABSTRACT FROM AUTHOR]

Damaged grains that are not useful for food or feed are abundant and cheap. The main objective of this paper was to valorize damaged rice grains for bioethanol production using presacchararification step followed by simultaneous saccharification and fermentation (SSF) by using waste brewer’s yeast. Presacchararification step was carried out using crude amylases that produce naturale isolate Paenibacillus chitinolyticus CKS1. Maltose, a fermentable sugar, was the main product during presaccharification. Statistical design, central composite design (CCD), was used for optimization of process parameters for ethanol production, yeast cell yield and utilized sugars. Under optimal conditions 0.5% malt extract, 3.84% inoculum and 2.76 days of fermentation maximum ethanol production of 4.69% was achieved. The obtained ethanol concentration was in a good correlation with yeast cell yield and utilized reducing sugars. The results obtained in this study indicate that the economical production of ethanol could be achieved using cheap waste materials also using low cost enzymes derivated from natural bacterial isolates. [ABSTRACT FROM AUTHOR]

Lubricating oils are used throughout the economy. This comprises lubricant types such as engine oils, compressor oils, hydraulic oils, machine oils, and metal working oils among other types. Succeeding their intended use span, a relevant share of lubricating oils can be recovered as waste oils which need to be treated as hazardous waste. In the EU, a legal and institutional framework has been established to ensure a high-quality recycling and a disposal that is compatible with the best public interest. To periodically evaluate the efficacy of the legal framework and its implementation in the EU member states, the end-of-life situation of waste oils needs to be investigated periodically. So far, there is no consistent method for the (retrospective) evaluation of the efficacy of the legal framework which can be adapted by the single states. In this article, a methodological framework for the analysis of waste oil flows on a country level is presented. While this framework explicitly focuses on the situation in the EU, its application to non-EU member states is possible, but potential differences in the availability of required input data need to be considered thoroughly. The presented calculation model is exemplarily applied to the situation in Germany and Belgium in 2015. In Germany about three quarters of the collected waste oil go to (domestic) re-refining. In Belgium, most waste oil is exported and re-refined abroad. [ABSTRACT FROM AUTHOR]

An active phosphate glass system co-doped with Nd 3+ and Yb 3+ rare earth, optically active ions was studied using steady-state and time-resolved luminescence spectroscopies. Because this system exhibits great potential for the development of multiple pump channel Yb 3+ lasers, this work attempts to identify losses in order to establish the limits of its radiative efficiency. To achieve this, multiple upconverted visible emissions related to Nd 3+ ions were observed in experiments carried out under near-infrared excitation at around 800 nm. An analysis was carried out to clarify if these upconverted emissions were governed by excited-state absorption of pump radiation or energy transfer between the rare earth ions. Another potential source of losses is related to energy back-transfer from Yb 3+ to Nd 3+ ions. However, no evidence of this phenomenon was observed, which is a good result for laser applications. Finally, the luminescence dynamics of the Yb 3+ ions were investigated in the framework of fast-diffusion processes. [ABSTRACT FROM AUTHOR]

A probabilistic approach to decision-optimal design and damage control is developed for structural systems that can gradually accumulate damage by nonlinear behavior under sequences of dynamic loads, whose occurrence can be idealized by renewal stochastic processes. To minimize consequences and damages during the life cycle of a structure, a damage threshold is established as a measure of damage control. If structural damages are lesser than such a damage threshold the structure is not repaired, otherwise the structure is repaired or rebuilt. The proposed approach is generalized and capable of describing particular cases for the optimization of expected losses. One of them is the well-known case used as a basis for many current design criteria in which it is assumed that the structure is repaired or rebuilt systematically after some damage or failure. The present work extends the ideas and models reported in several seminal papers. However, the proposed approach has the advantage that it takes into account cumulative structural damage over time, allows evaluating objectively the cost of damages and sets an optimum repairing damage threshold. Finally, the probabilistic formulation is illustrated through its application to a building subjected to sequences of earthquakes. [ABSTRACT FROM AUTHOR]

Concerning the primary aim of attending to the requirements used in the monitoring of induction motor efficiency, along with prioritizing a low intrusion level, the Literature presents various methods that need only the voltages, currents and some rotor speed cases. In a general sense, these methods estimate the torque on the machine shaft, along with calculate the output power and efficiency, through the use of a variety of different techniques. In this context, the present study proposes a real time wireless monitoring method over the operation conditions and efficiency of the three-phase induction motors. The method proposed herein estimates through the values measured on the three-phase voltages and currents and the equivalent circuit of the machine, the torque and speed of the shaft. Based on these estimates, both output power and efficiency can be calculated. The equivalent circuit of the machine is estimated through an iterative algorithm that uses only the data from the machine plate and the resistance of the stator, as will be shown in this study. [ABSTRACT FROM AUTHOR]

Modular multilevel converters (MMC) inherent features are gaining more attention for dc voltage transmission systems. One of the main research paths regarding the converter performance deals with its voltage modulation. Specifically, for medium voltage applications with relatively small number of submodules, the voltage modulation techniques impact on the MMC performance needs to be studied. This work provides an extensive review of the carrier-based pulse with modulation (CB-PWM) techniques proposed to be applied on previous multilevel inverter versions. The CB-PWM methods were adapted to be compatible with an additional cell ranking and selection algorithm to ensure equal energy distribution on the arm cells. The state-of-the-art of zero sequence signals (ZSS) applied on three-phase inverters is also reviewed. The alliance between the ZSS with the CB-PWM, as well as the nearest level modulation (NLM), has an important impact on the MMC harmonic content, efficiency and voltage ripple of its cells capacitors. A 15 MW 28-cell-based MMC is used to investigate each particular combination between the modulation method and the common mode ZSS. [ABSTRACT FROM AUTHOR]

Total or partial shading conditions have a significant impact rate on the capability of delivering energy, in addition to the on-site environmental condition which effects the PV module output production. Generally, the shading effect is caused by the PV generator inter-row configurations, cloudy perturbations, the buildings and trees. In this paper, an investigation study has been carried out by testing different PV module types (mono-crystalline, polycrystalline) under different shading rates. The obtained IV characteristics have been treated through the Bishop model where the power losses occurred on the PV module output, have been evaluated. The measured and estimated I-V characteristic plots illustrated a good agreement and the used model provides an accurate power losses prediction caused by different shading effects, even in desert areas. [ABSTRACT FROM AUTHOR]

Condensation is a very prevalent phenomenon both in nature and technology. It has a significant influence on the power and losses of the steam turbine for instance. Therefore, it is essential to investigate the effect of condensing flows on steam turbine losses and power, given the fact that the steam turbine is a common machine in many types of power plants based on fossil fuel combustion and nuclear or solar energy. This work aims to address the gaps in existing literature by presenting a comprehensive classification of losses caused by condensation in a 200 MW industrial-scale steam turbine low-pressure stage. Our study not only predicts the proportion of each loss type but also analyzes the impact of the gas model on condensation losses in detail. Firstly, a non-equilibrium condensation model is presented and the reliability and accuracy of the model is checked by comparing its results with the available experimental data in a nozzle and a steam turbine cascade. Secondly, the influence of the gas model on the losses is analysed in the nozzle. It is found that the CFD results of calculations using the real gas model fit the experimental data better than those obtained with the use of the ideal gas model. Also, the expansion line (process line) calculated by the real gas model is more reasonable, which indicates that the real gas model should be adopted in the condensation numerical calculation. Besides, the loss coefficients and efficiency are used to make a quantitative assessment of the CFD results. At last, the effect of the adiabatic and the non-adiabatic flow (considering non-equilibrium condensation) on the turbine performance is investigated numerically under a part-load (140 MW) and an over-load (216 MW) in a 200 MW industrial-scale steam turbine. It can be expected that the coexistence of aerodynamic and thermodynamic losses must lead to an interaction between them and in consequence to difficulties in loss identification in condensing steam flows. Besides, the thermal efficiency taking account of condensation decreases by about 0.7% compared with that ignoring the condensation phenomenon in part-load operating conditions, but the power value is slightly higher than that obtained if condensation is ignored, increasing by about 0.1 MW. However, it is not only thermal efficiency that drops substantially, but the obtained power is also reduced by approximately 0.42 MW under the over-load. It can be concluded that the power loss due to condensation can be reduced through an adequate decrease in overall power. The conclusions obtained from this work can provide the fundamental guidance for the industrial-scale steam turbine operation. [Display omitted] • A non-equilibrium condensation model is built and verified. • A clear classification of the losses is present for a 200 MW industrial-scale steam turbine. • The non-equilibrium condensation will significantly reduce the steam turbine thermal efficiency. • Power loss caused by the condensation can be decreased by suitably lowering the overall power in steam turbine. [ABSTRACT FROM AUTHOR]

The Sundarban Biosphere Reserve (SBR) in India is highly vulnerable to cyclones and tidal surges due to its geographical location and low-lying coastal morphology. This deltaic tract experiences frequent cyclones that incur loss of life and property. Despite this, the SBR lacks a systematic and effective disaster warning/management plan that benefits all residents/stakeholders. Hence, it is imperative to assess the mitigation measures currently in place to effectively counter the risks arising from an increasing frequency of tropical cyclones therein. This paper examines the efficiency of the existing early warning systems (EWS) and emergency preparedness in the SBR. Data was collected at the household level on EWS, community preparedness and the economic losses occurring due to cyclones in the last ten years through field surveys. The Poisson distribution model was used to understand the relation of losses with the EWS. Our results reveal that a lack of early warning awareness and delays in emergency preparedness have made coastal communities more vulnerable. The SBR lacks an adequate disaster management plan for minimizing such losses and policy interventions are urgently required to safeguard coastal communities during and in the aftermath of cyclones. Possible improvements in existing strategies for reducing cyclone vulnerability are suggested. [Display omitted] • Assessed the effectiveness of early warning systems (EWS) and emergency preparedness. • The Poisson distribution model was used to understand the relation of losses with EWS. • Lack of EWS and delay emergency preparedness have made coastal communities vulnerable. • Improvement in the existing EWS strategies for reducing cyclone vulnerability in the SBR. [ABSTRACT FROM AUTHOR]

Global population increase will require rapid increase of food production from existing agricultural land by 2050, which will inevitably mean the increase of agricultural productivity. Due to agricultural sustainable intensification since the 1990s, crop production in Huantai County of northern China has risen to 15 t ha − 1 yr − 1 for the annual wheat–maize rotation system. We examined the temporal dynamics of nitrogen (N) budget, N losses, and N use efficiency (NUE) during the 35 years (1980–2014) in Huantai. The results revealed that atmospheric N deposition increased 220% while reactive N losses decreased by 21.5% from 1980s to 2010s. During 1980–2002, annual N partial factor productivity (PFP N ), apparent NUE and N recovery efficiency (RE N ) increased from 20.3 to 40.7 kg grain kg − 1 N fert , from 36.5% to 71.0%, and from 32.4% to 57.7%, respectively; meanwhile, reactive N losses intensity, land use intensity and N use intensity decreased by 69.8%, 53.4%, 50.0%, respectively, but without further significant changes after 2002. Overall increases in NUE and decreases in N losses were largely due to the introduction of optimized fertilization practice, mechanization and increased incorporation of crop straw in Huantai. Straw incorporation was also significant in soil N stock accrual and fertility improvement. By 2030, northern China may reach the lowest end of PFP N values in developed countries (> 45 kg grain kg − 1 N fert ). These agricultural sustainable intensification practices will be critical in maintaining high grain yields and associated decreases in environmental pollution, although water use efficiency in the region still needs to be improved. [ABSTRACT FROM AUTHOR]

Forest inventories comprise observations, models and sampling. Airborne LiDAR has established its role in providing observations of canopy geometry and topography. These data are input for estimation of important forest properties to support forestry-related decision-making. A major deficiency in forest remote sensing is tree species identification. This study examines the option of using multi-footprint airborne LiDAR data. Features of such sensor design exist in recently introduced multispectral laser scanners. The first objective was to acquire radiometrically normalized, multi-footprint (11, 22, 44 and 59 cm) waveform (WF) data that characterize 1064-nm backscatter reflectance on the interval scale. The second objective was to analyze and validate the data quality in order to draw the correct conclusions about the effect of footprint size on WFs from natural and man-made targets. The experiment was carried out in Finland. Footprint variation was generated by acquiring data at different flying heights and by adjusting the transmitted power. The LiDAR campaign was successful and the data were of sufficient quality, except for a 1 dB trend due to the atmosphere. Significant findings were made concerning the magnitude of atmospheric losses, the linearity of the amplitude scale and the bandwidth characteristics of the receiver, the stability of the transmitter, the precision of the amplitude data and the transmission losses in canopies and power lines, as well as the response of WF attributes to footprint size in forest canopies. Multi-footprint data are a promising approach although the tree species-specific signatures were weak. [ABSTRACT FROM AUTHOR]

Frosty Pod Rot, caused by Moniliophthora roreri (Cif. & Par.) Evans et al. (1986), is considered the main pathogenic factor affecting the cocoa crops in Colombia and in other Central and South America countries. In this paper we present relevant characteristics of the disease with emphasis on the symptomatology, the life cycle and epidemiologic elements setting out the ground for its control. We also mention the results of three successful experiences in Colombia (the number of diseased pods obtained was the lowest) using strict removal of affected pods beginning once a week during the first three months and then every harvesting round as the main procedure of cultural control. The removed pods were discarded on the ground. [ABSTRACT FROM AUTHOR]

In this paper, the performance of both silicon carbide (SiC) MOSFETs and silicon (Si) IGBTs based electric vehicle (EV) traction systems are investigated and compared comprehensively, particularly from the efficiency point of view. Both conduction loss and switching loss of SiC-MOSFETs are analyzed and modeled taking temperature effect into account. Such approach yields a more accurate prediction of SiC losses. The temperature distribution of SiC-Inverter is described by ANSYS finite element analysis (FEA), and compared with Si counterparts. According to the lower losses and higher thermal conductivity, SiC exhibits much lower temperature than Si under the same power rating and cooling condition. Subsequently, this paper goes further by conducting an investigation of the effect of SiC-Inverter on the motor efficiency. Experimental results show that the SiC-based inverter-motor traction system has observably higher efficiency of overall system compared to the Si-based traction system, and first explore that the motor has extremely high efficiency under low speed and light load when it is driven by a SiC-MOSFETs based inverter due to the higher switching speed of SiC MOSFETs. Meanwhile, the experimental results also confirm the losses models of SiC MOSFETs. [ABSTRACT FROM AUTHOR]

The alternate arm converter (AAC) is an emerging dc-fault tolerant multilevel converter topology aimed at high-power and HVDC applications. This paper addresses the suitability of modular multilevel converter (MMC) submodules (SMs) for the AAC. Bipolar SMs are applicable for AACs depending on the complexity, controllability, device count, and operating losses. However, only the full-bridge SM (FB-SM) and the cross-connected SM (CC-SM) are fully controllable and functional in AACs. Based on the loss analysis of FB-SM- and CC-SM-based AAC with different device configurations, it is shown that: (i) complex SM structures do not benefit the operation of AAC, and (ii) the FB-SM provides the most functional advantages in an AAC. [ABSTRACT FROM AUTHOR]

Multi-terminal high voltage dc (HVdc) grids can eventually became a feasible solution to transport energy to remote and/ or distant areas and its exploitation depend, among other things, on the performance of the converter terminals. Therefore, to optimize the power transmission strategy along such a grid, it is necessary to recognize the efficiency of all the converters in all points of operation, namely with the different load conditions. In this vision, the aim of this work is to provide the methodology to model the modular multilevel converter (MMC) efficiency by means of a mathematical expression that can describe, over a broad range of active and reactive power flow combinations, the power losses generated by the semiconductors. According to the presented methodology, a polynomial-based model with a reduced number of coefficients is deducted, in such a way that can be directly used for optimal power flow (OPF) studies. The accuracy of the proposed model is characterized by an absolute relative error, at the worst scenario, approximately equal to 3%. [ABSTRACT FROM AUTHOR]

Previous research has shown that people are risk-seeking in the face of losses. We propose that this risk-seeking orientation is a palliative approach response to deal with a discrepancy between people's desire to avoid losses versus the possibility of loss. An expectancy violation (which induces behavioral approach responses) would therefore strengthen people's risk-seeking in the context of losses. Two experiments (Study 1 and Study 2) which were conducted in the context of the Asian Disease Problem demonstrated that people high in trait behavioral approach (trait BA) were more risk-seeking following an expectancy violation (state BA) than in a control condition. As expected, this was only the case for decisions framed in terms of losses, but not in terms of gains (Study 1). Taken together, our findings highlight the interacting motivational influences of situation-induced state behavioral approach and trait behavioral approach in understanding risky decision-making in the face of losses. [ABSTRACT FROM AUTHOR]

The Stirling machine has many successful applications mainly thanks to its high efficiency, fast cool-down, small size, light weight, low power consumption and high reliability (heating and cooling). A Beta type Stirling refrigerator is studied experimentally and numerically. The mathematical model takes into account complex phenomena related to compressible fluid mechanics, thermodynamics and heat transfer losses. A special attention is paid to the effect of geometric parameters such as dead and swept volumes respectively in compression and expansion spaces. Regenerator length, diameter and porosity are also discussed and optimal parameters are proposed. The effect of speed on the cold end temperature and refrigerator's performances is also investigated. Net cooling capacity, input power and COP were estimated at different conditions. Results allow understanding the physical processes occurring in the refrigerator and for predicting its performance. [ABSTRACT FROM AUTHOR]

Mechanical punching of electrical steels causes a degradation of their magnetic characteristics which can extend several millimeters from the cut edge. So, in the field of industrial applications, particularly that of small electrical machines, the stator core made of rigid and thin teeth would be subject to more losses. Thus, this topic of the effect of punching has to be submitted to further deep characterization and development in order to give some insight into the different mechanisms. In this framework, this paper evaluates the combined effect of punching and frequency on the magnetization curve and iron losses in thin SiFe and CoFe soft magnetic sheets. These alloys are typically suitable for the manufacture of high-speed electrical machines used in on board applications (aircraft power generators, automotive, etc). Two SiFe alloys and a CoFe alloy have been investigated. First, different rectangular samples of variable width (15, 10, 5, 3 mm) have been industrially punched. Then, a dedicated magnetic characterization has been made, using basically a mini-Epstein frame. Measurements have been performed from 50 Hz to 1 kHz and from 0.3 T to near saturation. Both rolling and transverse directions have been considered. Finally, a first attempt to predict the degradation due to the punching is presented. A useful description of the magnetic permeability as a function of B and f is given and the degradation parameters are estimated based on the knowledge of the reference permeability. [ABSTRACT FROM AUTHOR]

Turboexpander constitutes one of the vital components of Claude cycle based helium refrigerators and liquefiers that are gaining increasing technological importance. These turboexpanders which are of radial inflow in configuration are generally high-speed micro turbines, due to the low molecular weight and density of helium. Any improvement in efficiency of these machines requires a detailed understanding of the flow field. Computational Fluid Dynamics analysis (CFD) has emerged as a necessary tool for the determination of the flow fields in cryogenic turboexpanders, which is often not possible through experiments. In the present work three-dimensional transient flow analysis of a cryogenic turboexpander for helium refrigeration and liquefaction cycles were performed using Ansys CFX®, to understand the flow field of a high-speed helium turboexpander, which in turn will help in taking appropriate decisions regarding modifications of established design methodology for improved efficiency of these machines. The turboexpander is designed based on Balje's n s d s diagram and the inverse design blade profile generation formalism prescribed by Hasselgruber and Balje. The analyses include the study of several losses, their origins, the increase in entropy due to these losses, quantification of losses and the effects of various geometrical parameters on these losses. Through the flow field analysis it was observed that in the nozzle, flow separation at the nozzle blade suction side and trailing edge vortices resulted in loss generation, which calls for better nozzle blade profile. The turbine wheel flow field analysis revealed that the significant geometrical parameters of the turbine wheel blade like blade inlet angle, blade profile, tip clearance height and trailing edge thickness need to be optimised for improved performance of the turboexpander. The detailed flow field analysis in this paper can be used to improve the mean line design methodology for turboexpanders used in helium refrigeration and liquefaction cycles. [ABSTRACT FROM AUTHOR]

This paper discusses the losses analysis of low power high-frequency Wireless Power Transfer Systems (WPTSs). Ideal models for efficiency evaluation of WPTS can predict performances that are quite far from the real ones. The model proposed in this paper includes semiconductor devices losses, as well as modulation of duty-cycle and phase for the secondary side rectifier. The global influence of semiconductor devices and control parameters on the overall WPTS performances is numerically determined by solving the herein discussed non linear equations system. Experimental measurements realized on a 2 W@6.78 MHz WPTS demonstrate the validity of this analysis. [ABSTRACT FROM AUTHOR]

• Performance evaluation of different PV pumping systems installed in the south of Algeria. • The performance of the PVS was evaluated using the SV method. • Degradation assessment of 3 brands of sc-Si based technologies under outdoor tests. • The system losses estimation is used for degradation assessment. • PV panel degradation is between 0.88 and 2.44 %/year, which is related to the period of exposure. Any photovoltaic (PV) system technology must have been experienced for at least a year to provide valuable information about its seasonal behavior, which requires knowledge of the effects of each component of the PV installation chain. An experimental bench of different PV pumping systems using different PV panels was tested, which these PV systems (PVSs) consist of many brands of single-crystalline silicon (sc-Si) based technologies, including three manufacturers: ET-M53675, Isofotón (I-75 and I-100). This paper used the SV (sophisticated verification) method of analyzing and evaluating PVS performances in detail, for which we have developed a process to achieve good accuracy calculation, intended to estimate their various losses. This method was applied to the databases collected between 2014 and 2020. The output of real energy relative to its installed energy for four PVS configurations is between 72.7 % and 93.6 %, and in some cases it goes down to 48.8 %. This experimental study was extended to assess the degradation rate (DR) of PV panels exposed for long periods in the Saharan environment. Results show that after 2.5 years of operation for the ET-M53675 panels that are newly installed keep the same peak power, while PV panels that have been in operation for between 8 and 10 years have lost between 14.2 % and 19.5 % of their initial power value for Isofotón I-100 and Isofotón I-75 modules, respectively. The installed power in the Isofotón I-100 modules that have operated for more than 14 years has degraded by 23.59 %. This study is an effort to check and assess the feasibility of PVSs and the defects in PV modules found in newer and older installations in a desert environment at real operating conditions to enrich the databases concerning the DR of the various PV panels in the various environments around the world. [ABSTRACT FROM AUTHOR]

The growing need and interest for sustainability and preservation of our natural resources has long before been theoretically adapted and nourished in the minds and thoughts of Greek water professionals and Authorities executive associates. However, the long term planning and sustainable water management that aims at ongoing, constantly adaptable methodologies and strategies have not yet found a commonly practical application and have rather remained a discussion for almost every Water Utility in Greece. In 2013, the Utility of the city of Drama in northern Greece took the first step nationally towards the direction of implementing worldwide applied methodologies and IWA concepts. They realized that investing on a project that would ultimately provide them with the necessary equipment and the required know-how to assess their network's losses and the possible improvement interventions and strategies instead of just moving forward with changes without having previously estimated their results, makes more sense in the long term, capturing thus the essence of sustainability. The procedures, results and conclusions deriving from this project implementation will be presented within this paper. [ABSTRACT FROM AUTHOR]

In this study, a seismic risk analysis for Bucharest (Romania) is performed using six intermediate-depth Vrancea earthquake scenarios, defined as a function of magnitude, focal depth and source-to-site distance. For each scenario, 2000 individual ground motion simulations for Bucharest are considered. The simulations are performed using a recently derived spatial correlation model for Vrancea intermediate-depth seismic events. Subsequently, for each individual earthquake scenario, an estimation of the damage, losses and casualties is obtained. Moreover, a community resilience metrics, defined in terms of recovery of the housing capacity is evaluated using a model available in the literature. Finally, based on the recent experience of Italian earthquakes, an estimation of the number of operators and of the number of tents necessary after an earthquake is provided. [ABSTRACT FROM AUTHOR]

This paper presents an optimal and simultaneous allocation of the photovoltaic panel (PV) and wind turbine (WT) with the reconfiguration of radial distribution networks to reduce power losses cost and improve reliability. Determining the optimal optimization variables are very important to obtain the maximum benefits of renewable resource allocation and network reconfiguration, i.e. achieving the lowest losses and reliability cost. Problem optimization variables are the location, size and power factor of PV and WT as well as network tie-line switches states. Operational constraints include renewable sources size and radiality constraints. The optimization is conducted using an improved salp swarm algorithm (ISSA). Operators of the differential evolutionary (DE) algorithm are used to enhance the performance of conventional salp swarm algorithm (SSA) to prevent trapping in local optima and to increase the convergence speed in achieving the global optimal solution. The methodology is implemented on IEEE 33 and 69 bus distribution networks in various scenarios of renewable sources allocation and reconfiguration and simulation results including the cost of losses, cost of reliability improvement and net saving is presented before and after the optimization. The simulation results show that the ISSA is easily able to find the location and size of the renewable units optimally as well as the best network configuration in different scenarios. The results clear that optimal and simultaneous allocation of WTs and reconfiguration using ISSA has the lowest losses and reliability improvement cost, more net saving and better network performance than the other scenarios. The superiority of the ISSA is also confirmed in solving the problem in comparison with conventional SSA and also the previous studies. • ISSA is proposed for optimal and simultaneous allocation of the PVs and WTs with the reconfiguration of radial distribution networks. • The objective function is designed for reducing power loss costs and improving reliability. • Operators of the differential evolutionary (DE) algorithm are used to enhance the performance of conventional Salp Swarm Algorithm (SSA). • The superiority of the ISSA is confirmed in comparison with conventional SSA and also previous studies. [ABSTRACT FROM AUTHOR]

• A screening Normal Metal layer significantly decreases the spin wave losses caused by a lossy Ferromagnetic Material. • Metal/Air/YIG layered structure lead to higher confinement of the spin waves field within the air gap. • The power flow density at YIG/Air interface is maximal when the air gap of the layered structure is equal to a quarter wavelength of spin waves. We present theoretical and experimental results on the losses and confinement of spin waves (SW) in a Ferromagnetic/Normal Metal/Air/Ferrite multilayer structure. The above structure can be used for the creation of a desired topology of static magnetic field in a thin ferrite film, used as SW waveguide. It is shown that a screening Normal Metal (NMe) layer, inserted between SW waveguide and ferromagnetic (FM) layer, significantly decreases the SW losses caused by a lossy FM. It is also shown that the SW amplitude increases within the air gap (d) between a Ferrite film and NMe layer, when the gap satisfies the relation kd = 1, where k is SW wavenumber. The power flow density at Ferrite/Air interface is maximal when d is equal to a quarter wavelength of SW. [ABSTRACT FROM AUTHOR]

[Display omitted] • Continuous filament electrodes permit studies on electrode filament arrangements. • Continuous filament electrodes allow for side electrical contact without compression. • A common charge-transfer rate constant, k 0 of 2.2·10-4 cm s−1, was estimated. • Mass-transfer resistance improved with non-uniform filament spatial density. The most commonly used electrodes in redox flow batteries are carbon fiber felts, which are assemblies of randomly oriented short fibers. The avenues to improve cell performance are usually pre-treatment to enhance their catalytic activity, modifications of their porosity, and reducing resistivity by increasing compression. Our investigations focus on carbon electrodes made of continuous carbon filaments, where filaments were arranged in specific geometric patterns in order to investigate the effect of the fiber density and spatial distribution across direction of flow on the cell performance. To identify the source of cell voltage losses, electrochemical evaluations were performed with electrochemical impedance spectroscopy (EIS), and compared with commonly used felt electrodes. The electrochemically reversible ferri/ferrocyanide system at 50% state-of-charge (SOC) was used as redox probe for both anolyte and catholyte to avoid varying electrode activities of anode/cathode due to differences in redox species. The findings generate electrode design considerations to reduce voltage losses in redox flow batteries. [ABSTRACT FROM AUTHOR]

This paper aims to calculate an estimate of the initial stress voltage distribution in the transformer windings through their losses (that can be reduced by varying the construction parameters such as conductor section and size of the core window) through the numerical interpolation applied in capacitances of distribution transformers 30, 45, 75 and 112.5 kVA, 15 kV class. The calculations of the projects were organized into sets, with simultaneous variation of three construction parameters, totaling analysis of 10,648 projects of each power transformers arranged in three-dimensional arrays. The equation of the constant voltage distribution ( α -factor) according to the losses through the quadratic polynomial and cubic splines for the of LV and HV windings is formulated. [ABSTRACT FROM AUTHOR]

In this paper, symmetric spoof surface plasmon (SSP) mode on the doubly corrugated metal surfaces is indentified as long-range spoof surface plasmon (LRSSP) because of its extreme low propagation loss and symmetric dominant field profile so as short-range SSP (SRSSP) for anti-symmetric mode. Based on theoretical calculation and numerical simulation of finite integration method, symmetric and anti-symmetric SSP modes with various gap sizes between these two identical corrugated metal surfaces are investigated in terahertz (THz) regime and good agreement is realized. Besides, the low loss superiority of LRSSP diminishes along with the increased gap size. This work opens up new avenues to utilize this long-range surface mode in far-infrared, THz or lower frequency band and can find many potential applications such as low-loss waveguide, filters and novel electronic sources. [ABSTRACT FROM AUTHOR]

The power output delivered from a photovoltaic module highly depends on the amount of irradiance, which reaches the solar cells. Many factors determine the ideal output or optimum yield in a photovoltaic module. However, the environment is one of the contributing parameters which directly affect the photovoltaic performance. The authors review and evaluate key contributions to the understanding, performance effects, and mitigation of power loss due to soiling on a solar panel. Electrical characteristics of PV (Voltage and current) are discussed with respect to shading due to soiling. Shading due to soiling is divided in two categories, namely, soft shading such as air pollution, and hard shading which occurs when a solid such as accumulated dust blocks the sunlight. The result shows that soft shading affects the current provided by the PV module, but the voltage remains the same. In hard shading, the performance of the PV module depends on whether some cells are shaded or all cells of the PV module are shaded. If some cells are shaded, then as long as the unshaded cells receive solar irradiance, there will be some output although there will be a decrease in the voltage output of the PV module. This study also present a few cleaning method to prevent from dust accumulation on the surface of solar arrays. [ABSTRACT FROM AUTHOR]

Genetic Algorithm with special constraint handling procedure is proposed for the discrete optimization problem of capacitor placement and sizing in distribution system for cost reduction and power quality improvement. We use gene encoding that enables simple integer representation of possible different number of capacitors of various standard sizes to be placed on a bus. A pair-wise comparison in tournament selection operator is used so that it does not require any penalty parameter tuning, thus avoiding the most difficult aspect of the selection of appropriate penalty parameters. Proposed Penalty Free Genetic Algorithm (PFGA) is tested on 18-bus, 69-bus and 141-bus systems and the obtained results are better than the results from other methods. Simulations with different load models are also performed. It is shown that load models where active and reactive loads are voltage dependent, such as residential, commercial and industrial, constant Z and constant I model lead to completely different solutions. Therefore, careful load modeling should be put in place in order to obtain more realistic picture of the total savings. [ABSTRACT FROM AUTHOR]

We consider the Jaynes–Cummings model to describe the interaction of a Cooper pair box and a nanomechanical resonator in the presence of a Kerr medium and losses. The evolution of the entropy of both subsystems and the Cooper pair box population inversion were calculated numerically. It was found that population inversion and entropy increase when the frequency of the nanoresonator is time-dependent, even in the presence of losses; the effect is very sensitive to detuning and disappears in resonant regime. We also compare effects of the losses on each subsystem. [ABSTRACT FROM AUTHOR]

Wood biomass is one of the main sources of biofuel for bioenergy production worldwide. Generally, the exclusive use of comminuted biomass in automated boilers is preferred because these woodchips consist of homogeneous particles with a specified size. Wood biomass is harvested mainly in autumn and winter, whereas the demand for biomass-fired power stations is continuous throughout the year. Nevertheless, large amounts of woodchips are also produced in the spring and summer from residual materials obtained from the utilisation of conventional poplar plantations. This study focused on uncovered small and medium woodchip piles. In particular, the influence of form, density, and the size of piles on the biofuel quality during woodchip storage was analysed. The woodchip moisture contents and dry matter losses were considered when evaluating the storage dynamics. The results suggest that a storage system can be selected to service only the needs of thermal stations because any difference between the form (trapezoidal and cone), volume (35 and 70 m 3 ), and density of the piles was observed on woodchip quality analysis. In fact, a mean moisture content of 18% and average dry matter losses of 10% were recorded at the end of storage period for all treatments. Notably, the climate conditions and storage periods affected the results of this experiment. [ABSTRACT FROM AUTHOR]

Genes are frequently lost or gained in malignant tumors and the analysis of these changes can be informative about the underlying tumor biology. Retinoblastoma is a pediatric intraocular malignancy, and since deletions in chromosome 13 have been described in this tumor, we performed genome wide sequencing with the Illumina platform to test whether recurrent losses could be detected in low coverage data from DNA pools of Rb cases. An in silico reference profile for each pool was created from the human genome sequence GRCh37p5; a chromosome integrity score and a graphics 40 Kb window analysis approach, allowed us to identify with high resolution previously reported non random recurrent losses in all chromosomes of these tumors. We also found a pattern of gains and losses associated to clear and dark cytogenetic bands respectively. We further analyze a pool of medulloblastoma and found a more stable genomic profile and previously reported losses in this tumor. This approach facilitates identification of recurrent deletions from many patients that may be biological relevant for tumor development. [ABSTRACT FROM AUTHOR]

Perforated plates have many advantages compared to other differential type flow meters. Their permanent pressure loss could be lower than that of the standard orifice plates but significantly higher than that of the flow nozzles and the venturi meters. This high permanent pressure loss increases the energy consumption and hence the cost of flow metering. Therefore, the present study aims at minimizing the permanent pressure loss of perforated plates by optimizing their hole geometry. A convergent–divergent hole geometry is proposed for use with perforated plates. This geometry was numerically investigated and optimized by solving the Reynolds Averaged Navier–Stocks Equation (RANS) at different hole geometries. Numerical results show that the optimized convergent–divergent hole geometry reduces the permanent pressure loss by 51.7% at Reynolds number Re =3.5×10 4 . The discharge coefficient of the optimized perforated plate is higher than that of the flow nozzle and comparable to that of the venturi meter. Moreover, a significant improvement of the cavitation number was recorded for the perforated plate with optimized convergent–divergent hole geometry. [ABSTRACT FROM AUTHOR]