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High-speed gears are crucial transmission components found in airplanes and other systems, and they are maintained primarily through oil injection. However, due to their high operating speeds and the influence of oil injection settings, gear surface lubrication efficacy is frequently insufficient, compromising the transmission system's precision, durability, and safety. Currently, the parameter choices for oil injection in high-speed gears mostly rely on empirical judgment, which results in significant time and resource expenses. This study focuses on one pair of internal meshing gears within a specific aircraft gearbox, establishing an oil injection lubrication model for high-speed internal meshing gears using the computational fluid dynamics (CFD) approach. This research provides insights and references for optimizing oil injection parameters and improving lubrication efficiency in high-speed internal meshing gear systems by examining the dynamic characteristics of internal meshing wind resistance in addition to the effects of injection tube position, angle, and speed on lubrication performance. [ABSTRACT FROM AUTHOR]

Most existing architectural studies on ReRAM-based processing-in-memory (PIM) DNN accelerators assume that all weights of the DNN can be mapped to the crossbar at once. However, these studies are over-idealized. ReRAM crossbar resources for calculation are limited because of technological limitations, so multiple weight mapping procedures are required during the inference process. In this article, we propose a static scheduling framework which generates the mapping between DNN weights and ReRAM cells with minimum runtime weight programming cost. We first build a ReRAM crossbar programming latency model by simultaneously considering the DNN weight patterns, ReRAM programming operations, and PIM architecture characteristics. Then, the model is used in the searching process to obtain an optimized weight-to-OU mapping table with minimum online programming latency. Finally, an OU scheduler is used to coordinate the activation sequences of OUs in the crossbars to perform the inference computation correctly. Evaluation results show the proposed framework significantly reduces the weight programming overhead and the overall inference latency for various DNN models with different input datasets. [ABSTRACT FROM AUTHOR]

Prestressed concrete (PC) box girder is an innovative structure that is widely used in large-span bridges. Under eccentric loads such as vehicles, PC girders are inevitably under combined bending and torsion. To study its bending-torsional behavior, a refined full-range analysis model based on the combined action softening truss model (CA-STM) was proposed, where a simple and effective solution procedure and failure criteria were provided. The equilibrium equation, initial estimation equation for torque, and material constitutive model were modified by considering the prestressing effect to improve the CA-STM. An optimized algorithm was also employed to simplify the solution procedure instead of the traditional trial-and-error method, thus increasing the solution rate and stability. The theoretical curves predicted from the improved CA-STM exhibited great agreement with the available experimental results, and the predicted cracking and ultimate loads were also close to the experimental values. Hence, the improved CA-STM can reasonably predict the full-range mechanical response and failure modes of PC box girders subjected to combined bending and torsion, which provides great support to the design evaluation of such bridges. [ABSTRACT FROM AUTHOR]

Background and Objective: The purpose of this study was to determine if chronic periodontitis (CP) may induce hyperinsulinemia and may have the effect of on pancreatic β‐cell proliferation in a rat model. Materials and Methods: Twelve male Sprague–Dawley rats were divided into two groups: the CP group and the control group (Con group). The following contents were evaluated: pathological changes in periodontal soft and hard tissues; serum lipopolysaccharide (LPS) level, serum fasting insulin (FINS) level, fasting blood glucose (FBG) level, and homeostasis model assessment (HOMA) β (HOMA‐β) index; histopathological examination of islets; immunohistochemistry of insulin and p‐Smad2 expression in islets; immunofluorescence of changes in the relative number of β‐cells and the number of Ki67‐positive β‐cells. Western blotting was used to analyze p‐Smad2/Smad2 levels. Results were analyzed by two independent samples t tests. Results: Increased serum LPS level, FINS level, and HOMA‐β index were observed in the rats of the CP group; FBG level did not change significantly; histological assessments showed an enlarged islet area, increased insulin content, relatively increased β‐cells, increased Ki67‐positive β‐cells, and decreased p‐Smad2 expression in islets in the rats of the CP group. Conclusion: Our study results link CP‐induced hyperinsulinemia with changes in islets, such as islet hyperplasia and compensatory β‐cell proliferation, by using a CP rat model. [ABSTRACT FROM AUTHOR]

This article expounds on the challenges of sustainable global energy development to conventional econometrics in energy research. It introduces energy big data's "4V" characteristics, that is, volume, variety, velocity, and veracity. Further, the article presents a series of challenges the "4V" feature brings to conventional econometrics research on energy issues. Then, by reviewing the existing literature, the article proposes the improvement and promotion of conventional econometrics in the three directions of data exploration and variable generation, prediction, and causal inference of machine learning in big data. Finally, the article concludes that the discipline of econometrics will never go out of fashion. Although big data and machine learning will increasingly challenge the conventional econometrics research paradigm, econometrics will be reborn in the way of "phoenix nirvana". This article is categorized under:Emerging Technologies > Digitalization [ABSTRACT FROM AUTHOR]

Outdoor public spaces that provide a comfortable microclimate significantly contribute to urban livability. However, more elaborate investigations are needed to enhance the research-based design of landscape spatial form for optimal thermal comfort performance. This study aimed to optimize the morphological design of urban squares considering summer and winter microclimates by integrating multiple landscape elements of vegetation, waterbodies, buildings, and ground. The built environment microclimate simulation and validation of multi-physics coupling were conducted for thermal comfort, planar heterogeneity diagramming, and spatial typology identification. Further, research through design (RtD) was applied to reconstruct various spatial configurations and orientation forms to compare the relative thermal comfort areas of these geometrical prototypes in the target time period and square core zone. Among the landscape types, two identified spatial types for achieving better thermal comfort are the opening of a windward enclosure structure (ECS) that draws wind into the square in summer and an ECS without a windward opening that creates a more extended wind protection area in winter. Moreover, results of RtD show that the prototype with the smallest orientation angle to the prevailing wind direction has the most optimized thermal comfort during summer, while the form with a smaller angle to the prevailing wind direction is more favorable in winter. These findings provide methodological guidance for climate-adapted landscape square form optimization. [ABSTRACT FROM AUTHOR]

Poverty is a critical social problem in numerous countries. It is a result of many aspects and has been addressed worldwide for a long time. In this study, we construct the multidimensional poverty index (MPI) for migrant workers in China based on Amartya Sen's capabilities approach. Using the Chinese Family Panel Studies (CFPS) data during 2014–2020 and the Alkire–Foster methodology, our study examines the multidimensional poverty of migrant workers using static to dynamic analyses. The results show the following: (1) The multidimensional poverty of migrant workers shows a general decreasing trend over time. (2) Over one third of migrant workers are in severe multidimensional poverty. (3) The in-work poverty of migrant workers is serious, which is reflected in the indicators of employment security, housing provident fund, labor contract, and labor union. (4) Approximately 30% of migrant workers' multidimensional poverty is persistent. It is difficult for them to rid themselves of persistent poverty by their own effort. This study suggests that the government should pay more attention to poverty reduction and capability improvement for migrant workers. [ABSTRACT FROM AUTHOR]

The economic ethics is an abstract variable in economic system, and there is a correlation between the economic ethics and the sustainable economic growth. First of all, the existing researches are discussed from the macro perspective. On this basis, a set of economic ethics system is constructed. Afterwards, from the micro perspective, the necessary conditions for the growth of sustainable economics are obtained through the positive and negative benefit functions of the three dimensions of the government economic ethics, the enterprise economic ethics and the personal economic ethics under the condition of whether to abide by the law and whether to abide by ethics. Finally, the whole economic ethics system is analyzed and the conclusion is obtained that violating the economic ethics will hinder the sustainable growth of economy, while obeying the economic ethics will promote the sustainable growth of economy.

Based on a new development philosophy, this paper constructs an index system for measuring and evaluating high-quality developments in the Yellow River Basin using the entropy weight TOPSIS model and the obstacle degree analysis model to carry out a diagnostic analysis of the spatio-temporal differences in the level of high-quality development and obstacle factors in nine Yellow River Basin provinces from 2010 to 2020. The results show that: (1) During the period 2010–2020, the Yellow River Basin's high-quality development index showed a rising trend and the subindexes showed a trend of "coordinated development > shared development > green development > open development > innovative development". However, the overall level of high-quality development in the basin is not high, and there is still much room for improvement. (2) The global Moran's I of the high-quality development indexes in 2010, 2015 and 2020 are −0.216, −0.204 and −0.103, respectively, indicating that the level of high-quality development in each province and region within the Yellow River Basin is discrete and develops in a spatially unbalanced direction. (3) The obstacle degree analysis shows that green development, innovation development and open development are the main bottlenecks affecting the high-quality development of the basin. The restrictive role of green development is increasingly prominent, and the low level of scientific and technological innovation and achievement transformation, serious resource consumption and low resource utilization rate of industrial development, in addition to the low level of openness to the outside world are becoming key factors hindering the high-quality development of the provinces in the Yellow River Basin. [ABSTRACT FROM AUTHOR]

To study the effects of different parameters on the short-term stiffness and cracking load of precast laminated base slabs, static loading experiments were conducted on five base slabs to obtain their damage patterns, stiffness changes, and deflection. The parametric research on the base slab's short-term stiffness and cracking load was followed by changing the parameters, such as the truss height, truss spacing, and base slab thickness, using finite element refinement modeling based on test cases. The results show: (1) the ductility, short-term stiffness, and cracking load of the base slab can be significantly improved by reducing the truss spacing, and its short-term stiffness and cracking load with the 300 mm truss spacing are relatively improved by comparing to the 60 mm one; (2) increasing the height of truss improves the short-term stiffness, cracking load, and ductility of base slab; however, the improvements decrease with the increase of truss height. With consideration of the cost and construction requirements, the proper truss spacing is provided. [ABSTRACT FROM AUTHOR]

Halometallate ionic liquids provide new opportunities for industrial catalytic processes because of their unique blend of physical and chemical properties. Tunability underpins the success of ionic liquids because small structural changes can have drastic effects on either property. Catalysis can be optimised by adjusting structures to target properties such as Lewis basicity and acidity, but the structural changes have simultaneous impacts on physical properties. In this work, we provide a thorough, methodical, and reliable list of thermal parameters to help define temperature limits to prevent catalyst poisoning and limit the need to replace costly and environmentally demanding solvents. Mechanistic insights show that decomposition is particularly detrimental for halometallate ionic liquids, and life cycle analysis highlights that lower levels of organic cations are better for economic and environmental sustainability. [ABSTRACT FROM AUTHOR]

For a continuous random variable in real number field, there must be a distribution and also a probability density function of this random variable. If there is a known function with this random variable as independent variable, its image is a smooth or piecewise smooth line, there must be at least one function that takes this random variable as its independent variable, these functions are bounded on the image of the first function. Any one of these functions conduct line integral operation to the line segment or arc length of the certain image of the first known function is the cumulative probability of this continuous random variable interval corresponding to the section of the image for line integral operation. A general designation for these functions are linear probability density function of continuous random variables. Conduct line integral operation to the linear probability density function and conduct integral operation to the probability density function have same results of the cumulative probability of continuous random variable. By the way, Line integration including curve integration. According to the uniqueness of the probability, the existence and the number of linear probability density function can be proved and calculated.

Black phosphorus nanosheets (BPNSs) were synthesized with liquid exfoliation combined with the ultrasonic method and loaded with Fe3+ by simply mixing. The morphology, structure and electrochemical properties of the synthesized Fe3+/BPNSs were characterized by transmission electron microscopy (TEM), atomic force microscopy (AFM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and cyclic voltammetry (CV), etc. The load of Fe3+ can improve the electrochemical performance of BPNSs and enhance the sensitivity of the detection. Additionally, Fe3+/BPNSs display good biocompatibility. In this study, immunosensors based on Fe3+/BPNSs were constructed to detect alpha-fetoprotein (AFP). The detection is due to the specific binding between the AFP antigen and antibody on the surface of the immunosensors, which can reduce the current response of Fe3+/BPNSs. The immunosensors have a good linear relationship in the range of 0.005 ng·mL−1 to 50 ng·mL−1, and the detection limit is 1.2 pg·mL−1. The results show that surface modification with metal ions is a simple and effective way to improve the electrochemical properties of BPNSs, which will broaden the prospects for the future application of BPNSs in the electrochemical field. [ABSTRACT FROM AUTHOR]

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A new type of composite structure, the composite box girder with corrugated steel webs (CSWs) and trusses, is proposed recently. In order to investigate the structural behavior under positive and negative bending moments, flexural tests of the continuous girder were carried out, and the failure modes, deformation patterns, strain distribution, and development of the concrete cracks were investigated. Finite element analysis was conducted to investigate the effect of the range of concrete in the steel tube and the thickness of CSWs on the flexural behavior. The experimental and numerical results show that the test beam has a good ductility and integrity under flexural load. The contribution of CSWs to the flexural bearing capacity is very small and can be neglected. Besides, the plane section assumption is still valid when only top concrete slab and bottom steel tubes are concerned. The concrete filled in bottom steel tubes increases the stiffness and the bearing capacity of the girder. Equations to calculate the flexural bearing capacity under positive and negative bending moments were put forward and then verified with experimental results. [ABSTRACT FROM AUTHOR]

IonoSolv pretreatment using protic ionic liquids has shown impressive biomass fractionation performance and ionic liquid recyclability. Lignin condensation during ionoSolov pretreatment can lower its economic value and potentially limit the valorisation of lignin to produce high value materials. Organosolv pretreatment is known for generating a high-quality lignin fraction with a large potential for value-added applications. In this study, a hybrid fractionation process was designed based on ionoSolv and organosolv pretreatments, and was tested on two representative feedstocks, Miscanthus and pine. Compared to ionoSolv processing, the hybrid pretreatment displayed an improved fractionation performance by generating a cellulose-rich pulp which was more enzyme-accessible, and by removing a higher proportion of lignin. Saccharification yields reached 89% and 74% for Miscanthus and pine, respectively. The process was also able to maintain its high fractionation performance up to 50 wt% biomass loading. HSQC spectroscopy and GPC were used to characterise the isolated lignin. Alcohol induced α-alkoxylation took place during lignin fractionation and obstructed the lignin condensation, resulting in an improved quality lignin. A technoeconomic analysis was conducted for this new hybrid pretreatment, showing lower energy consumption for the IL regeneration step at a high organic solvent concentration, suggesting lower environmental impact and higher economic potential. This ionoSolv-organosolv pretreatment could be a milestone for the development of the current ionoSolv pretreatment at commercial scale. [ABSTRACT FROM AUTHOR]

The composite rigid-frame bridge presented in this study is a new type of structural solution that combines the steel–concrete composite box girder and the concrete-filled double-skin steel tube (CFDST) piers with rigid connecting joints. Compared with the conventional prestressed concrete rigid-frame bridge, it shows superior static and dynamic performances. This study performs shake table tests of a 1:10-scaled three-span steel–concrete composite rigid-frame bridge (SCCRFB) to explore its seismic characteristics and damage modes. The details of the bridge model design, construction, measurements, and testing process are presented. The seismic responses of the bridge under one typical near-fault and one far-field ground motions were experimentally investigated. Testing results revealed that the damage to the bridge is mainly located at the upper and lower ends of the CFDST piers, with yielding of the outer steel box and separation between the steel skins and infilled concrete. The testing results also indicated that the near-fault ground motions containing strong velocity pulse could significantly amplify the structural responses compared with the far-field ground motions. Furthermore, a detailed finite element (FE) model of the SCCRFB with CFDST piers is developed and validated by the experimental results, and numerical studies are then carried out to compare the seismic performances of this bridge type and the one supported by the conventional reinforced concrete (RC) piers. The numerical results show that the SCCRFB with CFDST piers exhibits superior seismic performances compared with the traditional bridge, especially when subjected to the near-fault ground motions. This study can provide useful references for the engineering solution and seismic design of long-span, high-pier composite rigid-frame bridges. [ABSTRACT FROM AUTHOR]