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The accurate perception of external environment information through the robot foot is crucial for the mobile robot to evaluate its ability to traverse terrain. Adequate foot-end contact signals can provide robust support for robot motion control and decision-making processes. The shape and uncertain rotation of the wheel-legged robot foot end represent a significant challenge to sensing the robot foot-end contact state, which current foot-end sensing schemes cannot solve. This paper presents a sensing method for the tire stress field of wheel-legged robots. A finite element analysis was conducted to study the deformation characteristics of the foot-end tire under force. Based on this analysis, a heuristic contact position estimator was designed that utilizes symmetrical deformation characteristics. Strain sensors, arranged in an array, extract the deformation information on the inner surface of the tire at a frequency of 200 Hz. The contact position estimator reduces the dimensionality of the data and fits the eigenvalues to the estimated contact position. Using support vector regression, the force estimator utilizes the estimated contact position and sensor signal to estimate the normal reaction force, designated as FZ. The sensing system is capable of detecting the contact position on the wheel circumference (with a root mean square error of 1.150°), as well as the normal force of 160 N on the Z axis (with a root mean square error of 6.04%). To validate the efficacy of the sensor detection method, a series of randomized and repeated experiments were conducted on a self-constructed test platform. This novel approach offers a promising avenue for perceiving contact states in wheel-legged robots. [ABSTRACT FROM AUTHOR]

This study investigates the performance of a 4-MIX engine utilizing hydrogen combustion in pure oxygen, water injection, and the application of the early-intake valve closure (EIVC) Miller cycle. Transitioning from a standard petrol–oil mix to hydrogen fuel with pure oxygen combustion aims to reduce emissions. Performance comparisons between baseline and oxyhydrogen engines showed proportional growth in the energy input rate with increasing rotational speed. The oxyhydrogen engine exhibited smoother reductions in brake torque and thermal efficiency as rotational speed increased compared to the baseline, attributed to hydrogen's higher heating value. Water injection targeted cylinder and exhaust temperature reduction while maintaining a consistent injected mass. The results indicated a threshold of around 2.5 kg/h for the optimal water injection rate, beyond which positive effects on engine performance emerged. Investigation into the EIVC Miller cycle revealed improvements in brake torque, thermal efficiency, and brake specific fuel consumption as early-intake valve closure increased. Overall, the EIVC model exhibited superior energy efficiency, torque output, and thermal efficiency compared to alternative models, effectively addressing emissions and cylinder temperature concerns. [ABSTRACT FROM AUTHOR]

Fat synthesis and lipolysis are natural processes in growth and have a close association with health. Fat provides energy, maintains physiological function, and so on, and thus plays a significant role in the body. However, excessive/abnormal fat accumulation leads to obesity and lipid metabolism disorder, which can have a detrimental impact on growth and even harm one's health. Aside from genetic effects, there are a range of factors related to obesity, such as excessive nutrient intake, inflammation, glycometabolism disease, and so on. These factors could serve as potential targets for anti-obesity therapy. Quercetin is a flavonol that has received a lot of attention recently because of its role in anti-obesity. It was thought to have the ability to regulate lipid metabolism and have a positive effect on anti-obesity, but the processes are still unknown. Recent studies have shown the role of quercetin in lipid metabolism might be related to its effects on inflammatory responses and glycometabolism. The references were chosen for this review with no date restrictions applied based on the topics they addressed, and the databases PubMed and Web of Sicence was used to conduct the references research, using the following search terms: "quercetin", "obesity", "inflammation", "glycometabolism", "insulin sensitivity", etc. This review summarizes the potential mechanisms of quercetin in alleviating lipid metabolism through anti-inflammatory and hypoglycemic signaling pathways, and describes the possible signaling pathways in the interaction of inflammation and glycometabolism, with the goal of providing references for future research and application of quercetin in the regulation of lipid metabolism. [ABSTRACT FROM AUTHOR]

Phrase comprehension (PC) aims to locate a specific object in an image according to a given linguistic query. The existing PC methods work in either a fully supervised or proposal-based weakly supervised manner, which rely explicitly or implicitly on expensive region annotations. In order to completely remove the dependence on the supervised region information, this paper proposes to address PC in a proposal-free weakly supervised training paradigm. To this end, we developed a novel cascaded searching reinforcement learning agent (CSRLA). Concretely, we first leveraged a visual language pre-trained model to generate a visual–textual cross-modal attention heatmap. Accordingly, a coarse salient initial region of the referential target was located. Then, we formulated the visual object grounding as a Markov decision process (MDP) in a reinforcement learning framework, where an agent was trained to iteratively search for the target's complete region from the salient local region. Additionally, we developed a novel confidence discrimination reward function (ConDis_R) to constrain the model to search for a complete and exclusive object region. The experimental results on three benchmark datasets of Refcoco, Refcoco+, and Refcocog demonstrated the effectiveness of our proposed method. [ABSTRACT FROM AUTHOR]

Nowadays, increasing the penetration of renewable heat technologies is an important approach to minimise global primary energy use and reduce CO2 emissions for a sustainable future. Thermoelectric heat pumps, which have some unique characteristics in comparison with conventional vapour compression heat pumps, can be integrated with solar thermal energy storage to form a promising renewable heat technology. However, currently, a reliable numerical model for TeHPs suitable for building energy simulation is lacking and the benefits achievable for a TeHP thanks to the integration with heat storage are unclear. To solve these issues, in this work, an experimental apparatus consisting of a water-to-air TeHP unit with a heat storage tank is modelled and tested for the first time, under the scenarios with thermal energy storage and without thermal energy storage, respectively. The results found that the developed numerical model could well predict the output performance of the TeHP unit, with deviations within 12%. Additionally, the output performance of the TeHP unit when combined with a heat storage tank is better than that of the TeHP unit without heat storage, in terms of the maximum temperature achieved in the testing box, the temperature response speed of the testing box, and the coefficient of performance (COP) of the TeHP unit. This work not only paves the way for the following building-integrated simulations of TeHP units, but also provides guidance for the design of the integrated systems that include TeHPs and thermal energy storage. [ABSTRACT FROM AUTHOR]

This paper investigated the effects of exhaust gas recirculation (EGR) on homogeneous charge compression ignition (HCCI) combustion in internal combustion engines. The exhaust valve closing (EVC) timings were scanned to obtain a set of baseline operating points for HCCI, and the coupling control of the internal and external EGR was explored. The results indicate that external EGR delays HCCI ignition timing and slows down the combustion speed. As the internal EGR rate increases, the maximum external EGR ratio that can be tolerated decreases. For HCCI detonation operating points with low internal EGR rates, the addition of up to 10% of external EGR can control the pressure rise rate peak to less than 10 bar/°CA, resulting in reduced fuel consumption and increased indicated mean effective pressure (IMEP). However, for HCCI operating points with high internal EGR rates, the effect of external EGR is mainly observed in the control of the pressure rise rate, with limited increase in IMEP. Additionally, an increasing external EGR rate leads to a significant decrease in nitrogen oxide (NOx) emissions, while carbon monoxide (CO) and hydrocarbon (HC) emissions slightly increase before engine misfire occurs. These findings suggest that the coupling control of internal and external EGR should be explored further, particularly in relation to reducing the negative valve overlap (NVO) angle and improving combustion efficiency. [ABSTRACT FROM AUTHOR]

This paper analyses and evaluates a design for a distributed renewable power system for a British winery. A winery in Wiltshire, England, is used for a case study. The consumption of this winery is first analysed, then potential means of generation are discussed. The resulting design is a combination of 156 1.6 × 1 m2 photovoltaic panels; a 2 × 12 m2 modular anaerobic digester using winery and farm waste to produce 0.00287 kg/s of biogas; and a biogas combined heat and power generator to supply 188 MWhe and 44 MWht per year. This was analysed technically, using ECLIPSE, and economically. The design would reduce the carbon footprint of a winery by 41,100 kgCO2/year. The techno-economic performance was compared with traditional power generation means; the designed system is technically viable, and financial incentives allow it to compete economically with alternatives. The cost of the design varies more with technology price than incentives, demonstrating that as technology improves incentives will quickly no longer be required. [ABSTRACT FROM AUTHOR]

A novel self-calibration comparator for a 12-bit 2.5 MSPS successive approximation register analog-to-digital converter (SAR ADC) applied in a touch microcontroller unit (MCU) with small area, high precision, fast response speed, and low-voltage detection is proposed in this paper. A combination of input/output offset storage (IOS/OOS) and an offset trimming circuit was employed to reduce the offset of the cascade preamplifier and the operational transconductance amplifier (OTA), a novel offset trimming circuit with a 5-bit digital controller was designed to further reduce the residual offset voltage, and an improved self-calibration technology was also implemented to compensate the conversion error in SAR ADC system to a minimum. Simulation and measured results show that the input-referred offset calibrating range is ±9.15 mV at 0.61 mV/step, the low-voltage detection of SAR ADC is realized by compensating the conversion error to a minimum, and the effective number of bits (ENOB) and figure of merit (FoM) at 5 V supply and 2.5 M/s rate in the 12-bit SAR ADC with a 95 nm CMOS are 11.33 bits and 726.6 fJ/conversion-step, respectively. The proposed self-calibration comparator applied in the SAR ADC system can automatically eliminate the offset voltage caused by nonidealities and meet the requirements of the touch MCU. [ABSTRACT FROM AUTHOR]

Diesel engines play a very significant role in the automotive industry, but the total emissions of diesel engines are more than 1.8 times that of petrol engines. It is therefore important for diesel engines to control emissions. Theoretically, the Miller cycle can be used to achieve NOx reductions by changing the effective compression ratio, while it has become increasingly popular in recent years with the increasing maturity of current turbocharging technology. Based on Ricardo WAVE software, this paper analyses the NOx emissions and engine performance of diesel engines by modelling and simulating their operation under different loads with two types of Miller cycles (EIVC and LIVC) at different degrees. Simulation of engines operating under different loads allows a more comprehensive study of the effects of the Miller cycle on the engine, and a specific analysis in the context of the actual engine operating environment. The result is that both versions of the Miller cycle are most effective in reducing NOx emissions at 10% load, showing a maximum reduction of 21% for EIVC and 37% for LIVC. However, as the Miller cycle decreases engine power, the paper further investigates the application of turbocharger systems in the EIVC Miller cycle, with results showing a 32% increase in brake power at 10% load and −25% EIVC Miller cycle degree. Both ethanol-fueled diesel-cycle and Miller cycle engines were also analyzed, and a reduction in NOx emissions was observed, as well as hydrogen engine performance and NOx emissions. [ABSTRACT FROM AUTHOR]

The free-piston engine is a type of none-crank engine that could be operated under variable compression ratio, and this provides it flexible fuel applicability and low engine emission potential. In this work, several 1-D engine models, including conventional gasoline engines, free-piston gasoline engines and free-piston hydrogen engines, have been established. Both engine performance and emission performance under engine speeds between 5–11 Hz and with different equivalent ratios have been simulated and compared. Results indicated that the free-piston engine has remarkable potential for NOx reduction, and the largest reduction is 57.37% at 6 Hz compared with a conventional gasoline engine. However, the figure of NOx from the hydrogen free-piston engine is slightly higher than that of the gasoline free-piston engine, and the difference increases with the increase of engine speed. In addition, several factors and their relationships related to hydrogen combustion in the free-piston engine have been investigated, and results show that the equivalent ratio φ = 0.88 is a vital point that affects NOx production, and the ignition advance timing could also affect combustion duration, the highest in-cylinder temperature and NOx production to a large extent. [ABSTRACT FROM AUTHOR]

A new design of a sorption-selective catalytic reduction (SCR) system is proposed to improve ammonia storage density and meet the ammonia demand for high NOx conversion efficiency at a relatively lower temperature (<100 °C) compared to urea-SCR systems. The major components are a main unit and a start-up unit that each contain a metal halide ammine as the sorbent. The start-up unit can operate without any external heat source, but spontaneously releases ammonia at the ambient temperature and is only used when the main unit is being warmed up for action. The selection criteria for the metal halide ammine for each unit is discussed. The working pair of SrCl2 as the main ammine and NH4Cl as the start-up ammine is further analyzed as an example to be used in the sorption-SCR system for a diesel engine, the NOx emissions of which were experimentally measured in different operation modes. Based on the experimental data of engine emissions and kinetic models of the chemisorption between ammines and ammonia, the dynamic performance of the sorption system with a total capacity of 180 L sorbent composite in different layouts was investigated and compared. It was found that the achievable desorption conversion degree was lower in smaller reactors and was more sensitive to operating conditions in smaller reactors compared to larger reactors. This suggests that a system using a small reactor layout requires some extra volume to completely meet the required capacity compared to a larger reactor layout. However, because systems with large reactors tend to respond slowly, as they have more thermal mass and take a longer time for preparation, there is a design trade-off required to have optimal performance and balance between the main unit and the start-up unit. In the case studied in this work, a system using three rechargeable reactors with a volume of 60 L each was found to be the preferable layout; it could have about a 90% desorption conversion degree and required around 10 min of warm-up time. Meanwhile, the coupled start-up unit should have a capacity of around 165 mL at least. [ABSTRACT FROM AUTHOR]

The CCHP system is a reasonable and effective method to improve the current situation of energy use. Capacity allocation is of great significance in improving the performance of the CCHP system. Due to the particularity of chemical enterprises' production process, the demand for cooling, heating, and power load is also relatively particular, which makes the dynamic loads challenging to be satisfied. Because of the above problems, the structure of the typical CCHP system is improved, embodied in the collocation of multi-stage lithium bromide chiller, and the use of various energy storage devices. Based on the improved ant lion intelligent optimization (ALO) algorithm, the comprehensive evaluation index coupled with energy benefit, economic benefit, and environmental benefit, is taken as the objective function, and the equipment capacity configuration of the CCHP system for chemical enterprises is studied. Considering winter, summer, and transition seasons, the results show that the system is better than the typical CCHP system. The annual cost savings of the new structural system are up to 13%, and the carbon dioxide emissions of the new structural system are reduced by up to 36.39%. The primary energy utilization rate of the new structure system is increased by 18%, and the comprehensive evaluation index also performs better. The optimal index can reach 0.814. [ABSTRACT FROM AUTHOR]

Many thermal resources are not reasonably used in the chemical industry's production process. To recover the waste heat from organic waste residue-calcium carbonate (CaCO3), which is added to inhibit hydrogen production, an organic Rankine cycle (ORC) system is applied in this research. An ORC system can reuse the low-temperature waste heat that is not fully utilized. In this study, the mathematical model of the biomass ORC power generation system is constructed. Five organic working fluids, R11, R113, R123, R141b, and R245fa, were selected from the physical characteristics and safety of working fluids. The system application case is the low-temperature heat absorption in a chemical industry's production process. The system is simulated by Aspen Plus V11 software, so as to study and analyze the influence of different working fluids and working conditions on the system performance and to obtain the preferred working fluids under different working conditions. At the same time, the economic evaluation and entropy method of the system are evaluated by using the investment profit rate PRI from different angles. It can be found that R11 and R141b have advantages, but R11 does not have advantages in environmental aspects. Through research, it is found that it is difficult to have a working fluid that can adapt to the biomass ORC power generation system under any working conditions. This paper can provide a basis for the subsequent research and selection of working fluids in the biomass ORC system. [ABSTRACT FROM AUTHOR]

Vienna rectifiers are widely used, but they have problems of zero-crossing current distortion and midpoint potential imbalance. In this paper, an improved hybrid modulation strategy is proposed. According to the phase difference between the reference voltage vector and the input current vector, the dynamic current crossing distortion sector is divided at each phase current crossing, and the discontinuous pulse width modulation strategy is adopted in the sector to suppress the redundant small vector mutation and improve the current crossing distortion. To solve the problem of midpoint potential balance, a space vector modulation strategy is adopted outside the sector to control the midpoint potential balance by allocating the time of small vector action by voltage balance factor. Finally, the effectiveness of the proposed method is verified by simulation and experiment. [ABSTRACT FROM AUTHOR]

The free-piston engine generator (FPEG) is a linear energy conversion device with the objective of utilisation within a hybrid-electric automotive vehicle power system. In this research, the piston dynamic characteristics of an FPEG is compared with that of a conventional engine (CE) of the same size, and the difference in the valve timing is compared for both port scavenging type and valve scavenging type, with the exhaust valve closing timing is selected as the parameter. A zero-dimensional simulation model is developed in Ricardo WAVE software (2016.1), with the piston dynamics obtained from the simulation model in Matlab/SIMULINK (R2017a). For the CE and FEPG using scavenging ports, in order to improve its power output to the same level as that of a CE, the inlet gas pressure is suggested to be improved to above 1.2 bar, approximately 0.2 bar higher than that used for a CE. If a CE cylinder with exhaust valves is adopted or referred to during the development of an FPEG prototype, the exhaust valve is suggested to be closed earlier to improve its power output, and a higher intake pressure is also suggested if its output power is expected to be the same or higher than that of a CE. [ABSTRACT FROM AUTHOR]

In this paper, validated simulations using Ricardo WAVE have been performed to investigate the effect of the Miller cycle and low-carbon fuels on the performance (power, torque, BTE and BSFC) and emissions of a diesel engine. The results show that the increased Miller cycle effect (larger deviation of the advanced or retarded intake valve closing from the standard intake valve closing time) will decrease NOx, CO and HC emissions, and slightly improve brake thermal efficiency (BTE) and brake specific fuel consumption (BSFC) with slight loss in engine performance and increase in soot emissions. An engine running B0 (diesel with 0% Biodiesel in the blend) with a −18% Miller cycle effect has a reduction in NOx of 9% and CO of 4.3% with a decrease of 1.6% in power at the rated engine speed. Using low carbon fuels drastically reduces emissions with reduced BTE and increased BSFC. When used in conjunction, the Miller cycle and low-carbon fuels have an improved effect on both performance and emissions. The optimal results demonstrate that using B60 (60% Biodiesel in the blend) and a −8% Miller effect contributes to a 1.5% improvement in power, 1.2% in BTE, 13.3% in NOx, 38.5% in CO, 8.9% in HC, and 33.0% in soot at a cost of 6.0% increase in BSFC. The results show that it is an easy way to reduce NOx, CO, HC and soot emissions and increase the BTE of the engine by combining Miller cycle and low-carbon fuels. [ABSTRACT FROM AUTHOR]

The thermal efficiency of an efficient gasoline engine is only about 40% and it will produce a large number of harmful products. Curbing harmful emissions and enhancing thermal efficiency have always been the goals pursued and emission regulations are also being tightened gradually. As one of the main consumers of fossil fuels, automobile engines must further reduce fuel consumption and emissions to comply with the concept of low-carbon development, which will also help them compete with electric vehicles. Homogeneous charge compression ignition (HCCI) combustion combined with variable valve actuation (VVA) technology is one of the important ways to improve engine emissions and economy. HCCI combustion based on VVA can only be realized at small and medium loads. The actual application on the entire vehicle needs to be combined with spark ignition (SI) combustion to achieve full working condition coverage. Therefore, HCCI combustion needs fast valve response characteristics; however, the valve lift and timing of the existing VVA mechanisms are mostly controlled separately, resulting in poor valve response. In order to solve this problem, the cam driven hydraulic variable valve actuation (CDH-VVA) mechanism was designed. The valve lift and timing can be adjusted at the same time and the switching of valve lift and timing can be completed in 1~2 cycles. A set of combustion mode switching data is selected to show the response characteristics of the CDH-VVA mechanism. When switching from spark ignition (SI) to HCCI, it switches to HCCI combustion after only one combustion cycle and it switches to stable HCCI combustion after two combustion cycles, which proves the fast response characteristics of the CDH-VVA mechanism. At the same time, the CDH-VVA mechanism can form the intake port exhaust gas recirculation (EGR), as one type of internal EGR. This paper studies the HCCI combustion characteristics of the CDH-VVA mechanism in order to optimize it in the future and enable it to realize more forms of HCCI combustion. At 1000 rpm, if the maximum lift of the exhaust valve (MLEV) is higher than 5.0 mm or lower than 1.5 mm, HCCI combustion cannot operate stably, the range of excess air coefficient (λ) is largest when the MLEV is 4.5 mm, ranging from 1.0~1.5. Then, as the MLEV decreases, the range of λ becomes smaller. When the MLEV drops to 1.5 mm, the range of λ shortens to 1.0~1.3. The maximum value of the MLEV remains the same at the three engine speeds (1000 rpm, 1200 rpm and 1400 rpm), which is 5.0 mm. The minimum value of the MLEV gradually climbs as the engine speed increase, 1000 rpm: 1.5 mm, 1200 rpm: 2.0 mm, 1400 rpm: 3.0 mm. With the increase of engine speed, the range of indicated mean effective pressure (IMEP) gradually declines, 3.53~6.31 bar (1000 rpm), 4.11~6.75 bar (1200 rpm), 5.02~6.09 bar (1400 rpm), which proves that the HCCI combustion loads of the intake port EGR are high and cannot be extended to low loads. The cyclic variation of HCCI combustion basically climbs with the decrease of the MLEV and slightly jumps with the increase of the engine speed. At 1000 rpm, when the MLEV is 5.0 mm, the cyclic variation range is 0.94%~1.5%. As the MLEV drops to 1.5 mm, the cyclic variation range rises to 3.5%~4.5%. Taking the maximum value of the MLEV as an example, the cyclic variation range of 1000 rpm is 0.94%~1.5%, 1200 rpm becomes 1.5%~2.3% and 1400 rpm rises to 2.0%~2.5%. [ABSTRACT FROM AUTHOR]

Simple Summary: Excessive fat deposit is one of the major problems in finishing Ningxiang pigs, and adversely affects the breeding. The study aimed to investigate the effects of diet with betaine supplementation (basal diet + 0.2% betaine) on the growth performance, slaughter performance, meat quality and the genes expression related to fat deposition in finishing Ningxiang pigs. The results indicated that diet with betaine supplementation decreased back fat thickness and fat percentage, and increased the lean meat percentage as well. In addition, it reduced the fat deposition by regulating the genes expression. These findings provided a reference for breeding Ningxiang pigs. The present study was conducted to investigate the effects of diet with betaine supplementation on the growth performance, carcass quality and fat deposition in finishing Ningxiang pigs. A total of 24 Ningxiang pigs (43.6 ± 5.34 kg of average body weight) was randomly divided into two groups, with 6 replicates per treatment and 2 pigs per replicate. The treatments included a control group (basal diet) and a test group (basal diet + 0.2% betaine). The whole trial lasted 81 days. At the end of the experiment, one pig (close to the average body weight of all experimental pigs) per replicate was slaughtered to determine the carcass traits, meat quality and the mRNA expression levels of genes relate to fat deposition (one pig per replicate was randomly selected and fasted for 12 h, n = 6). Results indicated that growth performance was not changed with betaine supplementation. However, dietary with betaine supplementation decreased back fat thickness and fat percentage, and increased the lean meat percentage as well (p < 0.05). In addition, diet with betaine supplementation reduced drip loss, water loss, cooking loss, shear force and b × 24 h value of meat (p < 0.05). There was no difference in total moisture, ether extract and crude protein of longissimus thoracis between the control and test group. Dietary with betaine supplementation decreased ether extract and total cholesterol (p < 0.05) in liver. Dietary with betaine supplementation upregulated the mRNA expression levels of adipose triglyceride lipase (ATGL) and sirtuin 1 (Sirt1), while downregulated the mRNA expression levels of fatty acid synthase (FAS) and acetyl CoA carboxylase (ACC) in subcutaneous fat of back (p < 0.05). Besides, dietary with betaine supplementation upregulated the fatty acid binding protein 4 (FABP4) mRNA expression of longissimus thoracis in finishing Ningxiang pigs (p < 0.05). These results showed that diet supplemented with betaine could improve the slaughtering performance and meat quality, and regulate the genes expression to affect the fat deposition in finishing Ningxiang pigs. [ABSTRACT FROM AUTHOR]

Polyoxymethylene dimethyl ether (PODE) is a low-viscosity oxygenated fuel that can improve the volatility of blended fuels. In this work, the macroscopic and microscopic spray characteristics of diesel-PODE3-4 under different ambient temperatures and injection pressures (IP) are studied. The studied blends consisted of pure diesel (P0), two diesel blend fuels of 20% (P20) and 50% (P50) by volume fraction of PODE3-4. The Mie scattering and Schlieren imaging techniques are used in the experiment. The results show that with the increase in IP, the vapor phase penetration distance and the average cone angle of the three fuels increased, and the Sauter mean diameter (SMD) of the three fuels decreased. When the ambient temperature increased, the vapor phase projection area and the average vapor phase cone angle of P20 and P50 increased, and the SMD decreased, but the vapor phase projection area of pure diesel did not change significantly. The results indicate that the blended fuel with PODE3-4 has better spray characteristics than P0 at low temperature, and the SMD hierarchy between the three fuels is P0 > P20 > P50. Through the visualization experiment, it is helpful to further understand the evaporation characteristics of different fuel properties and develop appropriate alternative diesel fuel. [ABSTRACT FROM AUTHOR]

This paper focuses on the investigation and optimisation of the Miller cycle, methanol, ethanol and turbocharging when applied to a high-performance gasoline engine. These technologies have been applied both individually and concurrently to test for potential compounding effects. Improvements have been targeted with regards to both emission output and performance. Also assessed is the capability of the engine to operate when exclusively powered by biofuels. This has been carried out numerically using the 1D gas dynamics tool 'WAVE', a 1D Navier–Stokes equation solver. These technologies have been implemented within the McLaren M838T 3.8L twin-turbo engine. The Miller cycle early intake valve close (EIVC) improved peak efficiency by 0.17% and increased power output at low and medium loads by 11%. Reductions of 6% for both NOx and CO were also found at rated speed. The biofuels achieved NOx and CO reductions of 60% and 96% respectively, alongside an efficiency increase of 2.5%. Exclusive biofuel use was found to be feasible with a minimum 35% power penalty. Applied cooperatively, the Miller cycle and biofuels were not detrimental to each other, compounding effects of a further 0.05% efficiency and 2% NOx improvements were achieved. [ABSTRACT FROM AUTHOR]

Simple Summary: The present study indicated that excessive energy enhanced fat deposition by upregulating expression of lipogenic genes in the longissimus thoracis of a Chinese fat-type pig. In addition, impairment in meat quality resulted in reduced meat tenderness and increased cross-sectional area of muscle fiber aroused by promoting glycolytic muscle fibers differentiation in muscles. These results provided a new perspective on the energy needs of Ningxiang pigs. This study investigated the effects of excessive or restrictive energy on growth performance, meat quality, intramuscular fat (IMF) deposition, and related gene expression in finishing Ningxiang pigs. A total of 36 Ningxiang pigs (43.26 ± 3.21 kg) were randomly assigned to three treatments (6 pens of 2 piglets per treatment) and fed by one of three dietary treatments until the pigs of each treatment weighed approximately 75 kg equally. The three treatments were control diet (digestible energy, DE:13.02 MJ/kg, CON), excessive energy diet (DE 15.22 MJ/kg, EE), and restrictive energy diet (DE 10.84 MJ/kg, RE). Results showed that EE improved average daily gain (ADG) and feed conversion ratio (FCR) (p < 0.01), while nothing significantly changed by RE except FCR increasing (p < 0.01). EE increased the content of IMF and triglycerides (TG) (p < 0.05), L*24h and b*45min (p < 0.01), while decreasing cooking loss and meat tenderness in longissimus thoracis (LT) (p < 0.05). b*24h was significantly increased with the increase of energy level (p < 0.01). Meanwhile, EE increased the cross-sectional area (CSA) of muscle fiber and the mRNA expression of myosin heavy chain (MyHC) IIb, acetyl CoA carboxylase (ACC), fatty acid synthase (FAS), and adipocyte fatty-acid binding protein (FABP4) (p < 0.05). In addition, throughout: A diet supplemented with excessive energy promoted IMF deposition by positively changing lipogenic potential while decreasing tenderness by increasing glycolytic muscle fibers, which together affected meat quality. In terms of growth performance and meat quality, the present study suggests that the low-energy diet is suitable for finishing Ningxiang pigs. [ABSTRACT FROM AUTHOR]

The United Kingdom has abundant renewable energy resources from wind, solar, biomass and others. Meanwhile, domestic sector consumes large amount of electricity and natural gas. This paper aims to explore the potentials of a hybrid renewable energy system (HRES) to supply power and heat for a household with the optimal configuration. A typical house in the United Kingdom is selected as a case study and its energy consumption is collected and analysed. Based on energy demands of the house, a distributed HRES including wind turbine, solar photovoltaic (PV) and biogas genset is designed and simulated to satisfy the power and heat demands. Hybrid Optimization Model for Electric Renewable (HOMER) Software is used to conduct this technoeconomic analysis. It is found that the HRES system with one 1-kW wind turbine, one 1-kW sized biogas genset, four battery units and one 1-kW sized power converter is the most feasible solution, which can supply enough power and heat to meet the household demands. In addition, the HRES system has the lowest net present cost (NPC) of $14,507 and the lowest levelized cost of energy (LCOE) of $0.588 kW−1·h−1. The case study is also quite insightful to other European countries. [ABSTRACT FROM AUTHOR]

There are few experimental reports combining hybrid energy storage and diesel engine generators as the power source of distributed power generation systems. In this article, a distributed power generation with energy storage system (DG-ES) which contains a diesel engine generator and an energy storage unit is set up and tested in the laboratory to satisfy the dynamic changing load. The hybrid energy storage system is composed of a lead-acid battery and a supercapacitor. The DG-ES supplied power to meet the domestic load demand successfully under different seasons. A simulation model of this system was also set up in MATLAB software used to guide to the experimental operation of this system. The simulation results has 2.69% and 2.35% error. The results of the experimental tests show the DG-ES can provide enough power to meet the dynamic loads of the selected house, especially at peak time in both winter and summer time. Computational simulation results show that the performance of DG-ES is improved by 3.61% in summer and 1.86% in winter when the system's operations are optimised. [ABSTRACT FROM AUTHOR]

Over 90% of global yam production is from West Africa where it provides food and income for above 300 million smallholders' farmers. However, the major challenge of yam is 10–40% post-harvest losses due to the lack of appropriate storage facilities. This paper assesses a biogas-driven cogeneration system, which could supply electricity and cold storage for 'yam bank' within a rural community. Considering 200 households' Nigerian village as a case study, crop residues are used as anaerobic digestion feedstock to produce biogas, which is subsequently used to power an internal combustion engine. Result shows that the system could store 3.6 tonnes of yam tubers each year and provide enough electricity for domestic and commercial activities. At the current electricity tariff of USD0.013·kWh−1 for rural areas, the system is unable to payback during its life span. The proposed USD0.42·kWh−1 by Nigerian Rural Electrification Agency seems good with less than 3 years discounted payback period but brings about extra burden on poor rural households. Based on the income from cold storage, electricity tariff of USD0.105·kWh−1 with an interest rate of 4% is suggested to be reasonable which results in 6.84 years discounted payback period especially considering non-monetary benefits of renewable energy system. [ABSTRACT FROM AUTHOR]

Small-scale organic Rankine cycle (ORC) systems driven by solar energy are compared in this paper, which aims to explore the potential of power generation for domestic utilisation. A solar thermal collector was used as the heat source for a hot water storage tank. Thermal performance was then evaluated in terms of both the conventional ORC and an ORC using thermal driven pump (TDP). It is established that the solar ORC using TDP has a superior performance to the conventional ORC under most working conditions. Results demonstrate that power output of the ORC using TDP ranges from 72 W to 82 W with the increase of evaporating temperature, which shows an improvement of up to 3.3% at a 100 °C evaporating temperature when compared with the power output of the conventional ORC. Energy and exergy efficiencies of the ORC using TDP increase from 11.3% to 12.6% and from 45.8% to 51.3% when the evaporating temperature increases from 75 °C to 100 °C. The efficiency of the ORC using TDP is improved by up to 3.27%. Additionally, the exergy destruction using TDP can be reduced in the evaporator and condenser. The highest exergy efficiency in the evaporator is 96.9%, an improvement of 62% in comparison with that of the conventional ORC, i.e., 59.9%. Thus, the small-scale solar ORC system using TDP is more promising for household application. [ABSTRACT FROM AUTHOR]