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In 2015, the Chinese government set ultra-low emission standards for thermal power to alleviate the pressure of increasing total pollutants from energy demand. This paper analyzes the policy effect of ultra-low emission in different regions based on panel data of 1202 thermal power enterprises, and the results of hierarchical linear model show that the total amount of air pollutants emitted by thermal power enterprises showed a decreasing trend during 2017–2021, realizing the dual control of concentration and total amount. Due to the differences in primary energy structure, industrial structure and economic development level of different regions, the total emission reduction of thermal power pollutants is affected differently. First, the proportion of the region's secondary industry in the region's GDP is negatively correlated with the decrease of the total pollutant emission of local thermal power enterprises. Second, the higher the per capita GDP of the region, the more significant the decrease in the total amount of pollutants, economic development is conducive to pollutant emission reduction. Third, the higher the proportion of thermal power in local energy, the more obvious the reduction of total pollutant emissions of thermal power enterprises, indicating that the implementation of ultra-low emission policies in these regions is more thorough. In addition, the environmental protection tax plays a positive role in the total emission reduction, and the higher the sulfur dioxide tax rate, the more significant the reduction of total pollutants of thermal power enterprises. To further reduce the total amount of pollutants in thermal power, more coordinated efforts of environmental and economic policies are needed. [Display omitted] • The ultra-low emission policy can achieve dual control of pollutants. • The total pollutant emission reduction has obvious regional differences. • Environmental protection tax can reduce the total amount of pollutants. • The coordinated emission reduction of different pollutants is not obvious. [ABSTRACT FROM AUTHOR]

In this latest work, the Newly Modified Robust Tensor Principal Component Analysis (New RTPCA) using affine transformation and L 2,1 norms is proposed to remove the outliers and heavy sparse noises in signal processing. This process is done by decomposing the original data matrix as the low-rank heavy sparse noises. The determination of the potential variables is casted as constrained convex optimization problem, and the Alternating Direction Method of Multipliers (ADMM) method is considered to reduce the computational loads in an iterative manner. The simulation results validate the effectiveness of the new method as compared with that of the state-of-the-art methods. [ABSTRACT FROM AUTHOR]

In this paper, we developed a new robust part-based model for facial landmark localization and detection via affine transformation. In contrast to the existing works, the new algorithm incorporates affine transformations with the robust regression to tackle the potential effects of outliers and heavy sparse noises, occlusions and illuminations. As such, the distorted or misaligned objects can be rectified by affine transformations and the patterns of occlusions and outliers can be explicitly separated from the true underlying objects in big data. Moreover, the search of the optimal parameters and affine transformations is cast as a constrained optimization programming. To mitigate the computations, a new set of equations is derived to update the parameters involved and the affine transformations iteratively in a round-robin manner. Our way to update the parameters compared to the state of the art of the works is relatively better, as we employ a fast alternating direction method for multiplier (ADMM) algorithm that solves the parameters separately. Simulations show that the proposed method outperforms the state-of-the-art works on facial landmark localization and detection on the COFW, HELEN, and LFPW datasets. [ABSTRACT FROM AUTHOR]

Optical Wireless Communications (OWCs) can play vital role in providing communication in healthcare infrastructure's, where contagious patients are admitted or treated as well as other patients are coming without any side effects as of radio frequency communication. In this paper, we propose high-speed cost-efficient free space optical (FSO) system for transmission of information (20 Gbps) inside healthcare premises comprising of number of buildings by integrating mode division multiplexing (MDM) scheme. The MDM scheme uses Laguerre Gaussian (LG) 00 and 01 modes whereas a simple On off Key (OOK) encoding scheme is employed for the proposed MDM-FSO system. The reported results show the efficient transmission of 20 Gbps data over 27 km of FSO link under clear atmospheric condition. Moreover, the proposed MDM-FSO link is evaluated under the impact of different fog conditions—low, medium and heavy. [ABSTRACT FROM AUTHOR]

Unit pricing for domestic waste, or pay-as-you-throw (PAYT), affords a promising policy option for waste classification and reduction at source. As an emerging economy, China intends to adopt the sophisticated instrument of unit pricing. The public attitude to this policy is of high relevance for its actual implementation. For the first time in China, this paper quantitatively examined the acceptability of the policy among urban residents by randomly delivering 632 questionnaires by taking Beijing, a megacity expected to introduce the practice, as an example. Based on the ordered logit model, determinants of acceptability were empirically tested including intrinsic, external and demographic factors. The results show that the acceptability rate of PAYT in Beijing is less than half, with the proportion of firm support reaching only 42.6%. The respectively low acceptability rate indicates substantial compliance costs, due to intensive resistance to policy implementation and more resources to be invested to promote acceptability. Empirical analysis further indicates that (1) regarding demographic features, aged or less educated residents tend to accept unit pricing, (2) as for intrinsic factors, a friendly environmental attitude, deeper understanding of charging policy and better social perception can significantly improve the public acceptability of the policy, and (3) in terms of external factors, better property services and transparent funding mechanisms play significant roles in enhancing public acceptability. These findings are further confirmed by replacing the dependent variable with either the willingness to pay for household waste disposal or the acceptability of the operated sewage treatment fee. The status of residents' preference for specific pricing methods is further investigated with underlying reasons being revealed. For developing regions with an urgent demand for waste reduction, it is proposed to install unit pricing in time to avoid possible growing social acceptability costs. Specific measures are proposed including changes in intrinsic factors, paying attention to focus groups, and building social consensus for unit pricing. [Display omitted] • Public acceptability of unit pricing policy is quantitatively examined in Beijing. • A random face-to-face survey is designed and conducted by covering 632 households. • The acceptability rate is only 42.6%, indicating high policy compliance costs. • Demographic, intrinsic and external factors play roles in improving acceptability. • Specific suggestions are proposed for regions like Beijing to introduce the policy. [ABSTRACT FROM AUTHOR]

Epoxy composites with excellent toughness and strength have been successfully fabricated by direct incorporation of graphite fluoride (GrF) without using any solvent or surfactant modification. Owing to the strong interfacial interactions, the glass transition temperature of GrF/epoxy composites exhibits a significant improvement as observed by dynamic mechanical analysis. Mechanical characterizations on GrF/epoxy composites suggest that the optimal increase of tensile strength and Young's modulus is achieved at a low filler concentration of 0.5 wt%, which is attributed to the favorable level of the GrF dispersion in the epoxy matrix. A maximum toughening effect is obtained at the concentration of 1 wt% GrF in the epoxy matrix with a 1.5-fold improvement in fracture toughness. The generation of crack pinning and crack deflection in epoxy due to the existence of GrF platelets is proposed to be the main toughening mechanism. Besides, microcracks resulted from pulling out, layer breakage and interfacial debonding of GrF platelets also contribute to the improvement in the fracture toughness of GrF/epoxy composites. [ABSTRACT FROM AUTHOR]

In this work, we propose a novel method for head pose estimation and face recovery, particularly to solve the potential impacts of noises in signal processing to get an efficient and effective model that is more resilient with annoying effects through adding affine transformation with the low-rank robust subspace regression. Consequently, the corrupted images can be correctly recovered by affine transformations to render more best regression outcomes. Thereby, we need to search so as to get optimal parameters which can be regarded as convex constrained optimization techniques. Afterward, the alternating direction method for multipliers (ADMM) approach is considered and a new set of updated equations is well established so as to update the optimization parameters and affine transformations iteratively in a round-robin manner. Additionally, the convergence of these new updating equations is well scrutinized as well. Thus, the experimental simulations reveal that the proposed method outperforms the state-of-the-art works for head pose estimation and face recovery on some public databases. [ABSTRACT FROM AUTHOR]

In this paper, we propose a novel robust algorithm for image recovery via affine transformations, the weighted nuclear, L ∗ , w , and the L 2,1 norms. The new method considers the spatial weight matrix to account the correlated samples in the data, the L 2,1 norm to tackle the dilemma of extreme values in the high-dimensional images, and the L ∗ , w norm newly added to alleviate the potential effects of outliers and heavy sparse noises, enabling the new approach to be more resilient to outliers and large variations in the high-dimensional images in signal processing. The determination of the parameters is involved, and the affine transformations are cast as a convex optimization problem. To mitigate the computational complexity, alternating iteratively reweighted direction method of multipliers (ADMM) method is utilized to derive a new set of recursive equations to update the optimization variables and the affine transformations iteratively in a round-robin manner. The new algorithm is superior to the state-of-the-art works in terms of accuracy on various public databases. [ABSTRACT FROM AUTHOR]

Conventional reconnaissance camera systems have been flown on manned aircraft, where the weight, size, and power requirements are not stringent. However, today, these parameters are important for unmanned aerial vehicles (UAVs). This article provides a solution to the design of airborne large aperture infrared optical systems, based on a monocentric lens that can meet the strict criteria of aerial reconnaissance UAVs for a wide field of view (FOV) and lightness of airborne electro-optical pod cameras. A monocentric lens has a curved image plane, consisting of an array of microsensors, which can provide an image with 368 megapixels over a 100° FOV. We obtained the initial structure of a five-glass (5GS) asymmetric monocentric lens with an air gap, using ray-tracing and global optimization algorithms. According to the design results, the ground sampling distance (GSD) of the system is 0.33 m at 3000 m altitude. The full-field modulation transfer function (MTF) value of the system is more than 0.4 at a Nyquist frequency of 70 lp/mm. We present a primary thermal control method, and the image quality was steady throughout the operating temperature range. This compactness and simple structure fulfill the needs of uncrewed airborne lenses. This work may facilitate the practical application of monocentric lens in UAVs. [ABSTRACT FROM AUTHOR]

Pointer meter is widely utilized in the fields of modern industry. Nowadays, intelligent inspection robots are gradually employed in place of labors for inspection task. Pointer meter recognition is one of the most important tasks of inspection robots. This article presents a lightweight pointer meter recognition algorithm, which is suitable for deployment on inspection robots. First, pointer meter is identified by pruned YOLOv5. Afterwards, the dial and the pointer are segmented through improved Deeplabv3+ in which the JPU and depthwise separable convolutions are utilized in lieu of dilated convolutions. After perspective transform and central-line extraction of pointer, the reading of the pointer meter can be determined using the angle method. Experimental results verify the FPS of pruned YOLOv5 improves 13.18% compared to original YOLOv5 and the FPS of improved Deeplabv3+ improves 45.74% compared to original Deeplabv3+. Additionally, the reading accuracy of the algorithm is 98.40% and average fiducial error is 0.32%, which indicate good accuracy. The relative standard deviation of reading is less than 1.4%, which indicates good stability of proposed algorithm. This study proposes a lightweight and accurate pointer meter recognition algorithm based on improved Deeplabv3+, the algorithm is ported to NVIDIA Jetson TX2 NX to verify its stability and accuracy. [ABSTRACT FROM AUTHOR]

Effective electromagnetic interference (EMI) shielding materials have garnered substantial interest for their efficacy in attenuating electromagnetic wave energy, ensuring data confidentiality, ensuring the operational stability of fragile electronic systems. To begin, artificially cultured diatom frustules (DF)-derived porous silica (DFPS) skeletons were constructed as templates in this study. Porous ceramics hot-pressed at 800 °C displayed a high compressive strength with a high specific surface area due to their three-dimensional (3D) multilayered and porous structures. Then, mechanically robust Ti 3 C 2 T x /DFPS composites with exceptional EMI shielding performance were fabricated by immersing porous DF-based ceramics into Ti 3 C 2 T x solutions and annealing in an argon environment to increase the materials' shielding efficiency (SE). The EMI SE of composites hot-pressed at 800 °C achieved the maximum EMI SE of 43.2 dB in the X-band and a compressive strength of 67.5 MPa, establishing a hitherto unreported balance of mechanical characteristics and shielding performance. Prolonged transmission paths, multiple dissipation, scattering and reflection of electromagnetic energy were achieved using a well-maintained hierarchical porous silica framework decorated with MXene, with adsorption caused by surface MXene serving as the primary shielding mechanism for the composites. Due to their superior overall performance, MXene/DFPS EMI shielding composites have a bright future in the aircraft sector as delicate electronic device components. [ABSTRACT FROM AUTHOR]

To solve the problem of inflexibility of offline hand–eye calibration in "eye-in-hand" modes, an online hand–eye calibration method based on the ChArUco board is proposed in this paper. Firstly, a hand–eye calibration model based on the ChArUco board is established, by analyzing the mathematical model of hand–eye calibration, and the image features of the ChArUco board. According to the advantages of the ChArUco board, with both the checkerboard and the ArUco marker, an online hand–eye calibration algorithm based on the ChArUco board is designed. Then, the online hand–eye calibration algorithm, based on the ChArUco board, is used to realize the dynamic adjustment of the hand–eye position relationship. Finally, the hand–eye calibration experiment is carried out to verify the accuracy of the hand–eye calibration based on the ChArUco board. The robustness and accuracy of the proposed method are verified by online hand–eye calibration experiments. The experimental results show that the accuracy of the online hand–eye calibration method proposed in this paper is between 0.4 mm and 0.6 mm, which is almost the same as the offline hand–eye calibration accuracy. The method in this paper utilizes the advantages of the ChArUco board to realize online hand–eye calibration, which improves the flexibility and robustness of hand–eye calibration. [ABSTRACT FROM AUTHOR]

Chitosan, as a hydrophilic, renewable, biodegradable, and cost-effective natural polymer, holds great promise in humidity sensor applications. This study proposes a green high-performance capacitive humidity sensor based on chitosan (CS)-sodium chloride (NaCl) composites. The CS-NaCl films were fabricated through a simple drip coating method, and their surface morphology and structure were characterized using SEM, XRD, FTIR and XPS techniques. The pure chitosan humidity sensor demonstrates an impressive response of 1180.17 % with excellent linearity. The introduction of NaCl markedly boosted the sensor response, with CS-50 wt% NaCl composites exhibiting a 72-fold increase (86, 492.84 %) in capacitance response compared to pure CS films. The contact angle test demonstrated that the chitosan film exhibited good hydrophilicity, which was further enhanced by the addition of NaCl. XRD and FTIR characterization confirmed that NaCl altered the structural properties of chitosan, disrupted hydrogen bonds, and consequently increased the mobility of polarizing groups and the dielectric constant. A water adsorption model was developed to elucidate the humidity sensing mechanism of the CS-NaCl sensor. The CS-NaCl composite material presents advantages such as easy preparation, high sensitivity, eco-friendliness, and promising practical applications in humidity sensing. [Display omitted] • Novel chitosan-based humidity sensor: green, cost-effective and easy to prepare. • Chitosan-sodium chloride humidity sensor with a greatly high capacitive response. • Enhanced interfacial and ionic polarization due to NaCl. • Excellent linearity of sensor response curve. [ABSTRACT FROM AUTHOR]

Abstract The green efficiency of water resources is important for industrial cleaner production and sustainable development. Existing studies pay much attention to the economic efficiency of water resource utilisation, ignoring its green efficiency. In order to solve this problem, an index of green total factor water efficiency (GTFWE) that can reflect the economic efficiency and green efficiency of water resources is constructed based on the DEA-SBM model with undesirable output. In addition, GTFWE is comprised of green total factor water management efficiency (GTFWME) and green total factor water environmental efficiency (GTFWEE) using the four-stage DEA model. The empirical results show that GTFWE in China's industry is at a low level, the effect of GTFWEE on GTFWE is generally increasing, and GTFWME is decreasing. However, there are large differences in these trends between regions and provinces in China. The GTFWME of Beijing, Tianjin, and seven other provinces needs improvement, while the GTFWME and GTFWEE of Hebei, Inner Mongolia, and other 15 provinces is low and also need improving. In contrast, both GTFWME and GTFWEE are high in the Shandong and Guangdong provinces. This paper provides a method for assessing GTFWE in China's industry and proposes some important policy implications for promoting the efficiency of China's industrial green total factor water resources. [ABSTRACT FROM AUTHOR]

This paper introduces a methodology to examine the effect of technological learning on industrial air pollutants intensity in China. It is based upon the theory of learning curves and environmental learning curves. In this way it is possible to estimate the effect of technological learning on industrial air pollutants intensity in two steps. First, we build a multi-factor environmental learning curve model to investigate the relationship between technological learning and industrial air pollutants intensity. At the second stage of the analysis, we assess whether and how different types of technological learning can reduce industrial air pollutants intensity based on a mediating effect model. The results show that there is a causal relationship between technological learning and industrial air pollutants intensity. Moreover, different types of technological learning have the same influence way on industrial air pollutants intensity: learning-by-doing can significantly reduce industrial air pollutants intensity through energy efficiency; and the same is true with learning-by-researching and learning-by-importing. In addition, different types of technological learning have different influence degree on industrial air pollutants intensity: learning-by-doing is the leading contributor to the reduction in industrial air pollutants intensity, while the contribution of learning-by-researching is the smallest. [ABSTRACT FROM AUTHOR]

[Display omitted] • The article provides a cost-effective and high-performance flexible aerogel for large-scale subambient daytime radiative cooling. • The aerogel cooler with hierarchically network structure provides a high solar reflectance and atmospheric window emissivity. • The radiative cooler exhibits high compression fatigue resistance and robust fire resistance. Radiative cooling is a passive cooling technology that radiates heat directly to outer space without any additional energy input and is therefore of great significance in reducing the consumption of energy. However, the radiative cooling in subambient daytime is difficult to implement and usually requires complicated structural designs, such as photonic crystals and metamaterials, which are neither cost-effective nor scalable. Here, we demonstrate that silica-alumina nanofibrous aerogels (SAFAs) synthesized by electrospinning can provide a high solar reflectance of ∼95 % and a high atmospheric window emissivity of ∼93 %, owing to the scattering reflection and selective emission of the fiber network in aerogel. During field tests, the SAFAs remain more than 5 °C below the ambient temperature, theoretically yielding a radiative cooling power of ∼133.1 W m−2. Through scalable manufacturing routes, the SAFAs exhibit high compression fatigue resistance, robust fire resistance and excellent thermal insulation. The low cost and high performance of these SAFAs present great potential for large-scale passive radiative cooling applications. [ABSTRACT FROM AUTHOR]

In the field of governing our "Plastic Planet", polylactic acid (PLA) has been considered to be a promising and ecologically friendlier alternative to traditional petroleum-based plastics. However, PLA-based products degrade slowly in the natural environment, likely resulting in a large accumulation of PLA waste worldwide in the near future. Herein, we have incorporated artificially cultured diatom frustules (DFs) into PLA, and found an improvement of more than eightfold on the degradation rate, from more than 24 months to 3 months or even less, as compared with the pure PLA. Mechanistic investigations illustrate that DFs change the degradation behavior of PLA from surface erosion to bulk erosion by the induced microfibril crystals. Simulation analysis verifies that the unstable crack propagation inside the PLA matrix greatly accelerates the degradation. The method developed in this work provides an efficient way to achieve rapid and adjustable degradation of biodegradable polymers for the urgent and widespread usage of green plastic productions. [Display omitted] [ABSTRACT FROM AUTHOR]

Waterborne bonded solid lubricating coatings (BSLCs) are normally prepared by physical blending, the basic components of which, however, exhibit poor wetting and dispersing properties and interfacial bonding strength. This article focuses on the structural design and chemical modification of waterborne polyurethane to optimize the adhesion of BSLCs thereof. By virtue of further compounding with polytetrafluoroethylene emulsions, a series of novel environmentally-friendly waterborne BSLCs have been successfully prepared, and then by adjusting the interface bonding between the resin and the lubricant in the coatings, the lubrication and wear resistance of the prepared BSLCs are systematically optimized. Experimental results demonstrate that the prepared waterborne BSLCs can effectively reduce the consumption of fossil resources and show superior physicochemical properties, lubrication and wear resistance, which are comparable to those of the organic solvent-based coatings. Furthermore, through systematic analysis of the damage morphology, structural variations and chemical compositions of the wear marks, the tribological mechanisms of the prepared BSLCs are illustrated. The current study help to promote the development of environment-friendly solid lubricating materials, and provides alternatives for the use of organic solvent-based BSLCs for reducing pollutions. [Display omitted] • Adhesion strength of the waterborne polyurethane is enhanced via chemical modification from level 5 to level 1. • Waterborne polyurethane BSLCs are novel green lubricating materials with superior physicochemical properties. • Tribological performances of waterborne coatings with mass ratio of 0.9 are comparable to the organic-based coatings. • Tribological mechanisms are systematically investigated concerning the wear marks. [ABSTRACT FROM AUTHOR]

Herein we design a fiber sensor able to simultaneously measure the temperature and the pressure under harsh conditions, such as strong electromagnetic interference and high pressure. It is built on the basis of the fiber-optic Fabry–Perot (F–P) interference and the temperature sensitive mechanism of fluorescent materials. Both halogen lamps and light-emitting diodes (LED) are employed as the excitation light source. The reflected light from the sensor contains the low coherent information of interference cavity and the fluorescent lifetime. This information is independent due to the separate optical path and the different demodulation device. It delivers the messages of pressure and temperature, respectively. It is demonstrated that the sensor achieved pressure measurement at the range of 120–400 KPa at room temperature with a sensitivity of 1.5 nm/KPa. Moreover, the linearity of pressure against the cavity length variation was over 99.9%. In the meantime, a temperature measurement in the range of 25–80 °C, with a sensitivity of 0.0048 ms/°C, was obtained. These experimental results evince that this kind of sensor has a simple configuration, low-cost, and easy fabrication. As such, it can be particularly applied to many fields. [ABSTRACT FROM AUTHOR]