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Featured Application: The application of this work is fuel cell hybrid electric vehicles. It solves the problem of balancing between the economy of the vehicle and the lifetime of the energy sources during the power distribution process. The energy management strategy plays an essential role in improving the fuel economy and extending the energy source lifetime for fuel cell hybrid electric vehicles (FCHEVs). However, the traditional energy management strategy ignores the lifetime of the energy sources for good fuel economy. In this work, an adaptive equivalent consumption minimization strategy considering performance degradation (DA-ECMS) is proposed by incorporating fuel cell and battery performance degradation models and establishing an optimal covariate predictor based on a long short-term memory (LSTM) neural network. The comparative simulations show that, compared with the adaptive equivalent consumption minimization strategy (A-ECMS), the DA-ECMS reduces the fuel cell stack voltage degradation by 17.1%, 23.2%, and 16.6% for the Worldwide Harmonized Light Vehicle Test Procedure (WLTP), the China Light-Duty Vehicle Test Cycle (CLTC), and the New European Driving Cycle (NEDC), respectively, and the corresponding battery capacity degradation is reduced by 5.1%, 11.1%, and 11.2%. The average relative error between the hardware-in-the-loop (HIL) test and simulation results of the DA-ECMS is 5%. In conclusion, the proposed DA-ECMS can effectively extend the lifetime of the fuel cell and battery compared to the A-ECMS. [ABSTRACT FROM AUTHOR]

The Yangtze River Basin serves as an essential ecological shelter in China, yet it has encountered escalating aquatic ecological challenges. Exploring the spatial–temporal changes and the trade-off–synergy relationships of water-related ecosystem services (WESs) is necessary for formulating management and planning policies targeting the sustainable development of watersheds. In this study, the InVEST model is utilized to evaluate the spatial–temporal variations in water yield (WY), water purification (WP), and soil conservation (SC) in the Yangtze River Basin using remote-sensed data from 2001 to 2021. The spatial overlay method and a correlation analysis were adopted to reveal the trade-off–synergy relationship among the three WESs. Additionally, we performed a comparative analysis across the grid and sub-basin scales. The results showed that the multi-year average WY, WP, and SC were 536.10 mm, 1.32 kg/ha, and 250.08 t/ha, representing increasing rates of 4.74 mm/a, −0.001 kg/ha/a, and 1.88 t/ha/a, respectively. Moreover, the trade-off–synergy relationships of WESs exhibited spatial variability; specifically, the WY-WP, WP-SC, and WY-SC pairs demonstrated reduced synergy magnitude over time. The WES interactions were stable across the scales of interest, while synergy strength showed noticeable variability. The findings may contribute to the sustainable development of the Yangtze River Basin and enhance the comprehensive management of WESs. [ABSTRACT FROM AUTHOR]

In recent years, deep convolutional neural networks (DCNNs) have shown promising performance in medical image analysis, including breast lesion classification in 2D ultrasound (US) images. Despite the outstanding performance of DCNN solutions, explaining their decisions remains an open investigation. Yet, the explainability of DCNN models has become essential for healthcare systems to accept and trust the models. This paper presents a novel framework for explaining DCNN classification decisions of lesions in ultrasound images using the saliency maps linking the DCNN decisions to known cancer characteristics in the medical domain. The proposed framework consists of three main phases. First, DCNN models for classification in ultrasound images are built. Next, selected methods for visualization are applied to obtain saliency maps on the input images of the DCNN models. In the final phase, the visualization outputs and domain-known cancer characteristics are mapped. The paper then demonstrates the use of the framework for breast lesion classification from ultrasound images. We first follow the transfer learning approach and build two DCNN models. We then analyze the visualization outputs of the trained DCNN models using the EGrad-CAM and Ablation-CAM methods. We map the DCNN model decisions of benign and malignant lesions through the visualization outputs to the characteristics such as echogenicity, calcification, shape, and margin. A retrospective dataset of 1298 US images collected from different hospitals is used to evaluate the effectiveness of the framework. The test results show that these characteristics contribute differently to the benign and malignant lesions' decisions. Our study provides the foundation for other researchers to explain the DCNN classification decisions of other cancer types. [ABSTRACT FROM AUTHOR]

To implement sustainable water resource management, the industries that produce a huge amount of wastewater are aiming to recycle wastewater. Reverse osmosis (RO) is an advanced membrane process that can produce potable water from wastewater. However, the presence of diverse pollutants in the wastewater necessitates effective pretreatment to ensure successful RO implementation. This study evaluated the efficiency of microfiltration (MF) and ultrafiltration (UF) as two pretreatment methods prior to RO, i.e., MF-RO and UF-RO, for recycling poultry slaughterhouse wastewater (PSWW). The direct treatment of PSWW with RO (direct RO) was also considered for comparison. In this study, membrane technology serves as a post treatment for PSWW, which was conventionally treated at Sanderson Farm. The results demonstrated that all of the processes, including MF-RO, UF-RO, and direct RO treatment of PSWW, rejected 100% of total phosphorus (TP), over 91.2% of chemical oxygen demand (COD), and 87% of total solids (TSs). Total nitrogen (TN) levels were reduced to 5 mg/L for MF-RO, 4 mg/L for UF-RO, and 9 mg/L for direct RO. In addition, the pretreatment of PSWW with MF and UF increased RO flux from 46.8 L/m2 h to 51 L/m2 h, an increase of approximately 9%. The product water obtained after MF-RO, UF-RO, and direct RO meets the required potable water quality standards for recycling PSWW in the poultry industry. A cost analysis demonstrated that MF-RO was the most economical option among membrane processes, primarily due to MF operating at a lower pressure and having a high water recovery ratio. In contrast, the cost of using RO without MF and UF pretreatments was approximately 2.6 times higher because of cleaning and maintenance expenses related to fouling. This study concluded that MF-RO is a preferable option for recycling PSWW. This pretreatment method would significantly contribute to environmental sustainability by reusing well-treated PSWW for industrial poultry purposes while maintaining cost efficiency. [ABSTRACT FROM AUTHOR]

In this paper, an effective numerical method is proposed for a linear complementarity problem (LCP) arising in the valuation of American bond options under the Cox–Ingersoll–Ross (CIR) model. Firstly, a variable substitution is used to simplify the linear complementary model. Secondly, the finite difference method is adopted to discretize the simplified model, and an equivalent variational form is obtained. Based on the positive definiteness of the discretized matrix, a projection and contraction method (PCM) is adopted for the resulting discretized variational problem. Finally, numerical experiments highlight the effectiveness and performance of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Although the existing cardiac diffusion tensor imaging (DTI) denoising methods have achieved promising results, most of them are dependent on the number of diffusion gradient directions, noise distributions, and noise levels. To address these issues, we propose a novel self-supervised cardiac DTI denoising network, Node2Node, which firstly expresses the diffusion-weighted (DW) image volumes along different directions as a graph, then the graph framelet transform (GFT) is implemented to map the DW signals into the GFT coefficients at different spectral bands, allowing us to accurately match the DW image pairs. After that, using the matched image pairs as input and target, a ResNet-like network is used to denoise in a self-supervised manner. In addition, a novel edge-aware loss based on pooling operation is proposed to retain the edge. Through comparison with several state-of-the-art methods on synthetic, ex vivo porcine, and in vivo human cardiac DTI datasets, we showed that the root mean square error (RMSE) of DW images and the average angular error (AAE) of fiber orientations obtained using Node2Node are the smallest, improved by 47.5% and 23.7%, respectively, on the synthetic dataset, demonstrating that Node2Node is not sensitive to the properties of the dataset. [ABSTRACT FROM AUTHOR]

This paper carried out wind tunnel tests and numerical analysis to study the effect of the spatial position of deflector plates on the vortex-induced vibration (VIV) of a double-deck truss girder. The wind tunnel tests found that setting the web deflector plate and the lower chord deflector plate significantly suppressed the VIV. In order to study the suppression mechanism of the deflector plate on VIV, numerical simulations were conducted using the computational fluid dynamics (CFD) method. We analyzed the suppression mechanism of the deflector plate on VIV by combining the vertical amplitude obtained by numerical simulation with the change in the vorticity magnitude and direction. The results showed that the flow velocity around the lower surface of the airflow was reduced, resulting in significantly lower vorticity at the exact position of the lower chord deflector plate and web deflector plate section compared to the original section. The web deflector plate and the lower chord deflector plate broke the vortex shedding mode in the wake flow region, and the vortex shedding frequency was far away from the self-oscillation frequency of the double-deck truss girder, thus suppressing the VIV. [ABSTRACT FROM AUTHOR]

Large-span suspension bridges are susceptible to wind loads. Therefore, a more precise analysis of their wind-induced vibration response is necessary to ensure the structure's absolute safety. This investigation conducted wind tunnel tests for the construction and completion stages to reveal the vortex-induced vibration (VIV) phenomenon of a double-deck suspension bridge. The results showed that no VIV occurred during the construction stage. However, the inclusion of railings significantly deteriorated the aerodynamic performance of the suspension bridge, leading to significant VIV at +3° and +5° wind angles of attack. Additionally, reducing the railing ventilation rate can significantly suppress the VIV amplitude. A new analysis method based on computational fluid dynamics (CFD) simulation is proposed to investigate the VIV mechanism of the double-deck truss girder. Twenty-nine measurement points were used to explore the vortex that causes VIV. The numerical simulations found that the area above and aft of the upper deck dominated the vertical VIV, while the aft of the lower deck dominated the torsional VIV. Furthermore, the intensity of the vortex in these areas was significantly lower during the construction stage. Moreover, reducing the railing ventilation rate significantly suppresses the torsional VIV by reducing the intensity of the vortex in the region behind the lower deck. [ABSTRACT FROM AUTHOR]

Root rot caused by Fusarium oxysporum is a serious root disease that affects the growth and yield of peanut crops worldwide. Identifying resistance genes is of great significance for both conventional and molecular breeding. At present, there are a few identified disease resistance genes, and the defense response mechanism against this pathogen remains unclear. Using transcriptome analysis techniques, 21 differentially expressed genes (DEGs) were identified in plants treated with Bacillus thuringiensis TG5 and carbendazim. Among these DEGs, the TIFY10A protein gene, pyruvate decarboxylase, and UDP glycosyltransferase 74B1 genes play an important role in early resistance to root rot in peanut plants, leading to regulatory factors that trigger immunity. Our study provides important information on the response mechanism of peanut plants to F. oxysporum-induced root rot and the protective benefits of colonization by the microbial pesticide, B. thuringiensis. [ABSTRACT FROM AUTHOR]

In this study, a modified maximum tangential stress criterion by considering T-stress and uniaxial compression tests have been utilized to theoretically and experimentally reveal the fracture initiation mechanism of a center-symmetric closed crack in compacted clay. The results show that wing cracks occur in the linear elastic phase of the stress-strain curve. In the plastic phase of the stress-strain curve, the wing cracks extend gradually and the shear cracks occur. The crack initiation stress and peak stress of compacted clay first decrease with the rise in pre-crack inclination angle (β = 0°–40°), and then increase with the rise in pre-crack inclination angle (β = 50°–90°). When the pre-crack inclination angle is relatively small or large (β ≤ 10° or β ≥ 70°), the crack type is mainly tension cracks. Secondary shear cracks occur when the pre-crack inclination angle is 10°–80°. When the dimensionless crack length is larger than 0.35, the crack types include wing-type tension cracks and secondary shear cracks. The experimental results were compared with the theoretical values. It was found that the critical size rc of compacted clay under compression-shear loading was 0.75 mm, smaller than the value calculated by the empirical formula (12 mm). The MTS criterion considering T-stress can be used to predict the compression-shear fracture behavior of compacted clay. [ABSTRACT FROM AUTHOR]

As sustainable structures like steel structures become more widely used, so do their construction issues. Improper lifting measures of long-span spatial steel structures may delay the construction period and even cause safety accidents. These problems have hindered the realization of sustainable buildings. Few studies on long-span spatial steel structures considered time-varying mechanical characteristics during the construction process. During the construction process, it will be found that the installed structure does not meet the required accuracy, and the installed content needs to be removed and re-constructed. This will cause idle work and rework, which will result in a waste of resources and is not conducive to sustainable development. Therefore, it is necessary to study the lifting construction process of long-span spatial steel structures and form a refined construction method. Based on the lifting construction process of the maintenance hangar roof of Chengdu Tianfu International Airport, this study proposes a time-varying mechanical analysis method for synchronous and asynchronous integral lifting of long-span space steel structures basing the Building Information Model (BIM). The force on the lifting point is analyzed during the hoisting construction process when the single-point asynchronous integral lifting and the interlaced point asynchronous integral lifting are carried out. The adverse effect of the displacement difference between lifting points during asynchronous integral lifting is proved. It provides a reference for the safe construction of long-span spatial steel structure lifting and also helps to improve the sustainability of construction projects. [ABSTRACT FROM AUTHOR]

The inter-regional freight volume is a crucial factor for transportation infrastructure planning and investment decision-making. However, existing studies on freight volume estimation have mainly focused on the total freight volume within a specific region, without taking freight flow into consideration. In this research, a gravity model was employed to estimate the inter-regional trade coefficient matrix based on the input–output tables of the 31 provinces in China in 2017. The inter-regional freight volume was then determined by converting the value flow into freight flow. To determine the model parameters, we used information from 2017 and subsequently validated the results using dates from 2012 to 2020. We also studied the impact of industrial structure change on freight volume by simulating dates from the aforementioned model in 2017. The results indicated that the model can effectively simulate inter-regional freight volume while taking into account the influence of industrial restructuring. [ABSTRACT FROM AUTHOR]

The long-span double-deck truss girder bridge has become a recommend structural form because of its good performance on traffic capacity. However, the vortex-induced vibration (VIV) characteristics for double-deck truss girders are more complicated and there is a lack of related research. In this research, wind tunnel tests were utilized to investigate the VIV characteristics of a large-span double-deck truss girder bridge. Meanwhile, the VIV suppression effect of the aerodynamic mitigation measures was measured. Furthermore, the VIV suppression mechanism was studied from the perspective of vortex shedding characteristics. The results indicated that the double-deck truss girder had a significant VIV when the wind attack angles were +3° and +5°. The aerodynamic mitigation measures had an influence on the VIV response of the double-deck truss girder. The upper chord fairing and lower chord inverted L-shaped deflector plate played a crucial role in suppressing VIV. Numerical analysis indicated that vortex shedding above the upper deck or in the wake region may dominate vertical VIV, while vortex shedding in the wake region of the lower deck may dominate torsional VIV. The upper chord fairing and lower chord inverted L-shaped deflector plate disrupted the original vortex shedding pattern in both regions, thereby suppressing VIV. This research can provide a foundation for bridge design and vibration suppression measures for large-span double-deck truss girder bridges. [ABSTRACT FROM AUTHOR]

This paper investigates the effects of support friction on mixed-mode I/II fracture behavior of compacted clay using notched deep beam (NDB) specimens under symmetric fixed support. Numerical models of 330 NDB specimens were established considering the crack inclination angle, crack length, support span, and support friction coefficient, and the normalized fracture parameters (YI, YII, and T*) of NDB specimens were calibrated. The numerical results showed that the values of YI, YII, and T* decreased at different degrees after considering the support friction. Notably, the support friction coefficient could significantly change the loading pattern at the crack tip. To verify this phenomenon, 12 compacted clay NDB specimens were prepared, and a mixed-mode I/II fracture test was performed under fixed support conditions; the phenomenon of asymmetric crack propagation was studied. The test data were processed using the numerical calibration results of YI, YII, and T* with and without consideration of friction. Afterward, the test data were compared and analyzed by combining the generalized maximum tangential stress (GMTS) and the maximum tangential stress (MTS) criteria. The analysis indicated that the real fracture characteristics of compacted clay NDB specimens could not be reflected when conducting mixed-mode I/II fracture tests under symmetric fixed support conditions if the test results were analyzed by YI, YII, and T* without considering support friction, as in previous studies. [ABSTRACT FROM AUTHOR]

Rock-socketed pile is widely used in coastal wharf, Marine bridge, and Marine power engineering, and the end bearing function is considered more in the design process. However, the lateral friction resistance of rock-socketed piles is an important bearing part, and the load transfer mechanism of the pile–soft rock interface is an important research focus. In this paper, a comparative analysis was adopted in the test, and ten groups of test specimens were made, including five groups of natural and saturated mudstone specimens, respectively. The characteristics of interfacial load transfer were analyzed through the shear test of a pile–mudstone interface. A calculation model for the vertical bearing capacity of rock-socketed piles based on the softening of lateral friction resistance was established, and the effects of interface relative displacement, lateral positive pressure, pile length, and pile stiffness on the vertical bearing capacity of rock-socketed piles were analyzed. The results show that the shear strength of the pile–rock interface is lower than that of the mudstone interface, and the interfacial shear strength shows the characteristics of "first increasing, then decreasing, and finally flattening with the increase of shear displacement". The vertical ultimate bearing capacity and residual bearing capacity under saturation were 89.49% and 89.73% of the natural state, respectively. With the increase of pile side pressure, the proportion of pile side friction resistance increased by 39.96%, and the pile side friction resistance was fully exerted. With the increase of pile length, the vertical ultimate bearing capacity of pile foundation increased, and the residual bearing capacity change value increased from 6.80% to 16.97%. However, the increase in pile stiffness had little effect on the vertical bearing capacity. The calculation model can provide a certain reference for the design and calculation of rock-socketed piles in soft rock areas. [ABSTRACT FROM AUTHOR]

Fire safety evacuation has been used in numerous different kinds of buildings. This research conducts a scientometric review of fire safety evacuation applications and advances in the buildings to clarify the research trends of fire evacuation in the future and provide guidance for relevant research. A total of 3312 journals and conference proceedings were analyzed through different dimensions. The result proves that evacuation environments concentrate mainly on residential building, commercial building, school, and railway station. The characteristics of the evacuee have been gradually refined in recent years, including children, the elderly, patients, and vulnerable groups. The main experimental approaches of fire safety evacuation are evacuation drills, site records, and VR/AR experiments. The crowd behavior models mainly consist of six types: a cellular automata model, a social force model, a lattice gas model, a game-theoretic model, an animal agent-based model, and a computer agent-based model. The analysis results in the theoretical method are becoming gradually closer to the behavioral characteristics and movement data of the crowd during the actual evacuation with improvements of practical considerations. The study of evacuation drills, disaster rescue, emergencies, and other external environmental factors will become the forefront of future research, and subway stations, airports, high-rise building, and other personnel places will be the focus of the study of crowd evacuation. [ABSTRACT FROM AUTHOR]

Underwater blasting technology has been widely used in inland waterway improvement projects. However, due to the particularity and complexity of underwater blasting, it is difficult to predict the transmission patterns of underwater blasting shock waves. Therefore, based on the Guoyuan Port Phase II project in Chongqing, the transmission patterns and influencing factors of underwater drilling blast shock wave pressure were investigated by field monitoring and numerical simulation. In this study, a total of 45 groups of shock wave pressures were measured, and the underwater shock wave pressure transmission formula obtained through data fitting was P = 27.39 × (Q1/3/R)1.25. Furthermore, the shock wave pressure transmission process in water was numerically simulated, and the simulation results were verified using field monitoring data. The results showed that the simulation and measured results were consistent. Finally, the influence of water depth, flow rate, and flow direction on the transmission pattern of shock wave pressure was analyzed, based on a numerical simulation method. The results showed that the more blastholes there are, the smaller the peak pressure of the shock wave. The lower the depth of blasting, the faster the decay of shock wave pressure. The flow rate has less effect on the shock wave pressure. At flow rates of 1, 2, 3, and 4 m/s in the range of 0 to 50 m, the shock wave pressure in the upstream flow decreased by 5.7%, 7.4%, 9.1%, and 10.2%, respectively, compared with that in the downstream flow. This study provides a theoretical basis for safety control of underwater drilling blasting engineering in inland waterways. [ABSTRACT FROM AUTHOR]

Poultry slaughterhouses produce a large amount of wastewater, which is usually treated by conventional methods. The traditional techniques face some challenges, especially the incapability of recovering valuable nutrients and reusing the treated water. Therefore, membrane technology has been widely adopted by researchers due to its enormous advantages over conventional methods. Pressure-driven membranes, such as microfiltration (MF), ultrafiltration (UF), nanofiltration (NF), and reverse osmosis (RO), have been studied to purify poultry slaughterhouse wastewater (PSWW) as a standalone process or an integrated process with other procedures. Membrane technology showed excellent performance by providing high efficiency for pollutant removal and the recovery of water and valuable products. It may remove approximately all the pollutants from PSWW and purify the water to the required level for discharge to the environment and even reuse for industrial poultry processing purposes while being economically efficient. This article comprehensively reviews the treatment and reuse of PSWW with MF, UF, NF, and RO. Most valuable nutrients can be recovered by UF, and high-quality water for reuse in poultry processing can be produced by RO from PSWW. The incredible performance of membrane technology indicates that membrane technology is an alternative approach for treating PSWW. [ABSTRACT FROM AUTHOR]

The Dallas-Fort Worth (DFW) area that experiences high temperature and intense solar radiation falls into the moderate nonattainment classification. The variation in meteorological parameters plays an important role in ambient ozone levels variation. Meteorological influences need to be decoupled from ozone data for long-term trend analysis. Temporal separation of maximum daily average 8-h ozone (MDA8 ozone), maximum daily temperature (TMAX), daily average solar radiation (DASR), and daily average wind speed (DAWS) were conducted using Kolmogorov-Zurbenko (KZ) filter for ozone records at Keller (C17), Arlington (C61), Red Bird (C402) monitoring stations in the DFW area from 2003 to 2017. Temporal separation, regression analysis, and meteorological detrending were performed. The long-term component had a clear and stable trend. The contribution of the long-term component to total variation was negligible, which is less than 2%. This is due to the removal of the data noise from the original time series data. The seasonal component had a major contribution (55% to 72%) in the total variation of the maximum temperature and solar radiation. However, the short-term component was dominant in the total variation of the MDA8 ozone (41–54%) and wind speed (68–79%). Regression analysis showed the baseline component bears the highest correlation than the short-term and raw. Solar radiation had the highest correlation to the MDA8 ozone, followed by temperature data in all three stations. Meteorological detrending showed the detrended long-term ozone had an increasing trend. The increasing trend was significant at C402 with a trend of 0.19 ± 0.006 ppb/y (0.398 R2), whereas slight increasing trends were found at C17 (0.072 ± 0.006 (0.107 R2)) and at C61 (0.019 ± 0.007 (0.005 R2)). The increasing trend of long-term components of MDA8 ozone was justified by the increasing level of NOx and VOCs from the mobile sources in the DFW area. [ABSTRACT FROM AUTHOR]

Chitosan has emerged as a biodegradable, nontoxic polymer with multiple beneficial applications in the agricultural and biomedical sectors. As nanotechnology has evolved as a promising field, researchers have incorporated chitosan-based nanomaterials in a variety of products to enhance their efficacy and biocompatibility. Moreover, due to its inherent antimicrobial and chelating properties, and the availability of modifiable functional groups, chitosan nanoparticles were also directly used in a variety of applications. In this review, the use of chitosan-based nanomaterials in agricultural and biomedical fields related to the management of abiotic stress in plants, water availability for crops, controlling foodborne pathogens, and cancer photothermal therapy is discussed, with some insights into the possible mechanisms of action. Additionally, the toxicity arising from the accumulation of these nanomaterials in biological systems and future research avenues that had gained limited attention from the scientific community are discussed here. Overall, chitosan-based nanomaterials show promising characteristics for sustainable agricultural practices and effective healthcare in an eco-friendly manner. [ABSTRACT FROM AUTHOR]

Unconventional oil and gas extraction generates large quantities of produced water (PW). Due to strict environmental regulations, it is important to recover and reuse PW. In this study, commercial polyethersulfone (PES) ultrafiltration (UF) membranes were surface-modified with zwitterionic polymer 3-(3,4-Dihydroxyphenyl)-l-alanine (l-DOPA) solution to alleviate membrane fouling during the ultrafiltration of shale oil PW of the Permian Basin. UF membranes were coated in l-DOPA solution by using a dip coating technique. Membrane characterization tests confirmed successful l-DOPA coating on UF membranes. While performing the experiments, permeate flux behaviors of the uncoated and coated membranes and antifouling resistance of the zwitterionic coating were evaluated. Among the coated UF membranes with varying coating times from one day to three days, the three-day coated UF membrane showed a good flux performance and the highest fouling resistance. The flux reduced by 38.4% for the uncoated membrane, while the reduction was 16% for the three-day coated membrane after the 5 h ultrafiltration of PW. Both improvements of the flux performance and recovery ratio are attributed to a negatively-charged surface developed on the membranes after the zwitterionic coating. The UF pretreatment also improved the flux behavior of the later forward osmosis (FO) process for PW treatment. [ABSTRACT FROM AUTHOR]

Electricity generation from coal is one of the leading contributors to greenhouse gas emissions in the U.S. and has adverse effects on the environment. Biomass from forest residue can be co-fired with coal to reduce the impact of fossil-fuel power plants on the environment. W. A. Parish power plant (WAP, Richmond, TX, USA) located in the greater Houston area is the largest coal and natural gas-based power generation facility in Texas and is the subject of the current study. A life cycle assessment (LCA) study was performed with SimaPro® and IMPACT 2002+ method, for the replacement of 5%, 10%, and 15% coal (energy-basis) with forest residue at the WAP power plant in Texas. Results from the LCA study indicate that life cycle air emissions of CO2, CO, SO2, PM2.5, NOX, and VOC could reduce by 13.5%, 6.4%, 9.5%, 9.2%, 11.6%, and 7.7% respectively when 15% of coal is replaced with forest residue. Potential life cycle impact decreased across 9 mid-point impact categories of, human/aquatic toxicity, respiratory organics/inorganics, global warming, non-renewable energy, mineral extraction, aquatic acidification, and terrestrial acidification/nitrification. The potential impact across damage/end-point categories of human health, ecosystem quality, climate change, and resources reduced by 8.7%, 3.8%, 13.2%, and 14.8% respectively for 15% co-firing ratio. [ABSTRACT FROM AUTHOR]

The last decade witnessed a quantum increase in wind energy contribution to the U.S. renewable electricity mix. Although the overall environmental impact of wind energy is miniscule in comparison to fossil-fuel energy, the early stages of the wind energy life cycle have potential for a higher environmental impact. This study attempts to quantify the relative contribution of individual stages toward life cycle impacts by conducting a life cycle assessment with SimaPro® and the Impact 2002+ impact assessment method. A comparative analysis of individual stages at three locations, onshore, shallow-water, and deep-water, in Texas and the gulf coast indicates that material extraction/processing would be the dominant stage with an average impact contribution of 72% for onshore, 58% for shallow-water, and 82% for deep-water across the 15 midpoint impact categories. The payback times for CO2 and energy consumption range from 6 to 14 and 6 to 17 months, respectively, with onshore farms having shorter payback times. The greenhouse gas emissions (GHG) were in the range of 5–7 gCO2eq/kWh for the onshore location, 6–9 CO2eq/kWh for the shallow-water location, and 6–8 CO2eq/kWh for the deep-water location. A sensitivity analysis of the material extraction/processing stage to the electricity sourcing stage indicates that replacement of lignite coal with natural gas or wind would lead to marginal improvements in midpoint impact categories. [ABSTRACT FROM AUTHOR]