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In order to design an involute spline made of PEEK (polyetheretherketone)-based material with better performance and improve the design rules of involute splines, initially, an involute splines design theory for PEEK (polyetheretherketone)-based materials is presented, which combines international standards (ISO 4156, 1. 2. 3, 2005), American standards (ANSI B92.2M. 1989), and traditional empirical formulas. Second, using the involute splines calibration method in international standards as a guide, we developed the involute splines calibration method for PEEK-based materials by estimating the impact of energy consumption caused by viscoelasticity on temperature field calibration. Next, the contact characteristics of the designed spline were analyzed using ABAQUS2022 software to confirm the accuracy and reliability of the design and calibration methods. Finally, finite element simulation was used to analyze the influence of different pressure angles, moduli, combined lengths, and other parameters on the contact characteristics of the spline in order to realize the optimal design of PEEK-based material involute splines, to offer a theoretical foundation and improved design methodology for cylindrical straight-tooth involute splines. [ABSTRACT FROM AUTHOR]

Glass curtain walls (GCWs) have become prevalent in office buildings, owing to their lightweight and modular characteristics. However, their lower thermal resistance, compared to opaque walls, results in increased energy consumption. Incorporating phase-change materials (PCMs) provides a viable solution through which to address the susceptibility of GCWs to external conditions, thus enhancing thermal performance and mitigating energy concerns. This study delves into the influences of the glazing solar heat gain coefficient (SHGC), the glazing heat transfer coefficient (U-value), and PCM thickness on the energy performance of buildings. Using Design Builder (DB) software version 6.1.0.006, a multi-story office building was simulated in different climatic zones in China, covering the climatic characteristics of severe cold, cold, hot summer and warm winter, cold summer and winter, and mild regions. The simulation results quantitatively elucidated the effects of the glazing parameters and the number of PCMs on thermal regulation and energy consumption. A sensitivity analysis identified the glazing SHGC as the most influential factor in energy consumption. Additionally, by employing Response Surface Methodology (RSM), the researchers aimed to achieve a balance between minimal building energy consumption and economic cost, ultimately determining an optimal design solution. The results demonstrated significant energy savings, ranging from 20.16% to 81.18%, accompanied by economic savings, ranging from 15.78% to 79.54%, across distinct climate zones in China. [ABSTRACT FROM AUTHOR]

Glass curtain walls (GCWs) have become prevalent in office buildings, owing to their lightweight and modular characteristics. However, their lower thermal resistance, compared to opaque walls, results in increased energy consumption. Incorporating phase-change materials (PCMs) provides a viable solution through which to address the susceptibility of GCWs to external conditions, thus enhancing thermal performance and mitigating energy concerns. This study delves into the influences of the glazing solar heat gain coefficient (SHGC), the glazing heat transfer coefficient (U-value), and PCM thickness on the energy performance of buildings. Using Design Builder (DB) software version 6.1.0.006, a multi-story office building was simulated in different climatic zones in China, covering the climatic characteristics of severe cold, cold, hot summer and warm winter, cold summer and winter, and mild regions. The simulation results quantitatively elucidated the effects of the glazing parameters and the number of PCMs on thermal regulation and energy consumption. A sensitivity analysis identified the glazing SHGC as the most influential factor in energy consumption. Additionally, by employing Response Surface Methodology (RSM), the researchers aimed to achieve a balance between minimal building energy consumption and economic cost, ultimately determining an optimal design solution. The results demonstrated significant energy savings, ranging from 20.16% to 81.18%, accompanied by economic savings, ranging from 15.78% to 79.54%, across distinct climate zones in China.

• A bibliometric analysis of the relevant literature on tunnel lighting was conducted. • The literature is sorted by energy saving, visual comfort, and low carbon. • The relationship between energy saving and low carbon is discussed. • The relationship between energy saving and comfort is also discussed. • The optimization methods of tunnel light environment are summarized. A reasonable and applicative tunnel light environment is important to ensure driving safety. This review aims to contribute to this growing area of research by exploring the tunnel lighting, which expands from safety to visual comfort, energy saving, and low carbon This paper employs bibliometric method to a visual analysis of the relevant literature and summarizes current research efforts and development directions. Firstly, the literature is visually presented by CiteSpace to elaborate the state-of-art with the dimensions of the timeline graph, the keyword co-occurrence graph, and the institutions & countries co-occurrence graph. Afterwards the literature is reviewed from three major perspectives: energy saving, visual comfort, and low carbon. Current research is mainly on luminaire arrangement, auxiliary lighting and other measures to reduce energy consumption. Visual comfort is mainly improved by optimizing the light environment's physical quantities, e.g. luminance, color temperature, color rendering etc. Current measures to achieve low carbon targets include green energy, green photoconductivity, green luminaires and green operation. Energy saving, visual comfort and low carbon are interrelated and complementary. However, a systematic understanding of how tunnel lighting contributes to carbon emission is still lacking. There is still room for development in tunnel lighting to achieve full intelligent control and the goal of carbon neutrality. [ABSTRACT FROM AUTHOR]

The traditional hydraulic transmission system for wheel loaders is inefficient and, in power matching, prevents improvement in performance during spading and transport. This paper proposes a power reflux hydraulic transmission system (PRHTS) with a capacity adjustment device, which retains both flexible transmission and the advantages of the low-speed high-torque characteristics while improving transmission efficiency, and the capacity adjustment device can meet the requirements for the capacity factor of the hydraulic transmission system during spading and transport. Based on numerical calculations and an analysis of the basic characteristics of the proposed PRHTS, a method for the optimal design of power matching systems for wheel loaders is proposed. The results for matching show that compared with traditional hydraulic transmission systems, the proposed method increases the range of the high-efficiency working area (η ≥ 75%) during transport by 384 r·min–1, enhances average efficiency during transport by 10.99%, reduces the average working fuel consumption rate by 10.61 g·(kW·h)–1, and increases the average output power by 36.72 kW while ensuring the original power performance and fuel economy of the wheel loader during spading. [ABSTRACT FROM AUTHOR]

This paper presents an optimized design method for an LCL filter for a grid connected photovoltaic system. This method is based on the Fast Fourier Transform (FFT) of the current and voltage which provides the current ripples thus allowing to find the LCL filter passives elements. A trick which consists of inductances fragmentation is adopted in order to reduce the volume and the cost of the filter. Then, we do an analysis taking into account the impact of our neighbors' consumption. This system is controlled by a decoupled active and reactive power control (PQ control) using a Phase Locked Loop (PLL) for the system's synchronization. Finally, we present and discuss the results of our simulation obtained by Matlab software (simulink and simpowersystems) in order to highlight the proposed study. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of the present paper is to study the X-ray energy utilization efficiency that is inherent in the improved design of actual X-ray digital imaging systems in industrial applications. Both the X-ray energy utilization efficiency and the light intensity of the X-ray beam are lowered distinctly while the distance of the focal length is increased for high spatial resolution and high sensitivity. Furthermore, the utilization efficiency is even lowered for improving the tube current to maintain the light intensity. The theoretical analysis and the experimental results show that the sensitivity, spatial resolution and X-ray energy utilization efficiency should be synthetically considered in an optimized X-ray imaging system. [Copyright &y& Elsevier]

The power reflux hydraulic transmission system (PRHTS) with a capacity adjustment device presents a high transmission efficiency, a wider range of high-efficiency area (η ≥ 75%), low speed, high torque, and adjustable capacity factor to correspond to the various working modes of a wheel loader. Herein, based on the working principle of a capacity adjustment device and cluster analysis of V-pattern working condition data, the shift strategy of a capacity adjustment device was designed. By combining the output characteristics of the PRHTS and V-pattern working condition data analysis, the optimal gear ratio was developed. The simulation results demonstrated that, in a V-pattern working condition, the average transmission efficiency of the PRHTS and traction were improved by 6.94% and 8.74%, respectively, based on the shovel efficiency and fuel consumption which are consistent with the traditional hydraulic transmission system. In traction conditions, the average traction force increased by 20.92%, the dynamic factor increased by 19.75%, and the average constant-speed fuel consumption per 100 km decreased by 11.66%, which considerably improved the power and fuel economy of the wheel loader during traction conditions. [ABSTRACT FROM AUTHOR]