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Copyright of Integrated Intelligent Energy is the property of Editorial Department of Integrated Intelligent Energy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Engineering Management / Gongcheng Guanli Xuebao is the property of Journal of Engineering Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents a method to establish typical operating conditions for train traction systems by combining site-based short trip analysis with nonparametric tests, in order to overcome various obstacles, such as inadequate efficiency testing results based on rated points of train traction systems, which often fail to accurately reflect the actual energy efficiency level of systems during long-distance operation under multiple conditions, and the existing absence of typical operating conditions essential for supporting the evaluation of traction systems' energy efficiency levels and guiding the energy-saving design of products. First, short trips were categorized, screened and randomly combined. Then, the optimal short-trip combination was identified through nonparametric tests. Subsequently, the typical operating conditions were developed, taking the traction system of an electric locomotive model as a case study. Furthermore, the proposed method was verified by analyzing errors in operating characteristic parameters and assessing the similarities in velocity-force (V-F) distribution probability two-dimensional matrix. The verification results revealed a deviation between the constructed typical operating conditions and the characteristic values derived from sampled data at 4.54%, and the consistency in V-F distribution probabilities at 98.06%. These findings indicate that the method proposed in this paper accurately reflects the actual operating characteristics of train traction systems, with the established typical operating conditions closely aligning with the actual operating conditions of train traction systems, underscoring their potential for aiding in energy-saving design and energy efficiency evaluation for train traction systems.

【Objective】This paper discusses full lifecycle energy efficiency of optical communication systems in the purpose of energy conservation and carbon reduction. It aims to establish a universal model for description of energy efficiency, which covers all stages of system lifecycle, and it is not limited to specific technologies or network structures. It also analyzes the key influencing factors for improvement of energy efficiency of optical communication systems.【Methods】This paper explores the useful work and energy consumption of optical communication systems, to establish a universal model for energy efficiency. In the expression of useful work, in addition to the commonly used factor data rate, distance factor is introduced as an important factor. The paper recommends that the value generated by data transmissions which meet specific quality requirements and maintaining network connectivity in specific scenario applications should be considered in the description of the useful efficacy. The description method is named as comprehensive useful efficacy. In the discussion of energy consumption, the system lifecycle is decomposed into four stages: manufacturing, installation and construction, operation and maintenance, and waste recycling. Main influencing factors of energy efficiency improvement are discussed based on the established model.【Results】Main results of the research include: (1) Distance factor can be one of the main factors for evaluating the useful work of a system, and distance factors affect energy consumption at various stages of the system's lifecycle; (2) For new scenarios and applications, setting weights for data transmissions which meet specific quality requirements and assigning values for maintaining connectivities status in description of the system useful work could reflect the value brought by the energy cost of the system to meet the needs of scenario applications; (3) Energy consumption factors of each stage of the life cycle should be considered in evaluation of energy consumption of the full lifecycle, and the energy consumption of each stage should be converted into unit time based on the system operating life for accumulation; (4) Optimized network topology and routing design, reduction of line losses, as well as evolution of optical transmission technology and equipment/facility energy saving technologies, are important means to reduce energy consumptions throughout the entire lifecycle of the system and improve the energy efficiency.【Conclusion】This paper discusses the comprehensive useful work and full life cycle energy consumption of optical communication systems, and establishes a universal model to describe the full life cycle energy efficiency of the system. This model takes distance as an important influencing factor in the expression of the useful efficiency and also energy consumption of the system, which corresponds the value of the optical communication system based on communication distance with the energy consumption in the life-cycle caused by distances. It also suggests considering the value generated by data transmissions which meet specific quality requirements and maintaining network connectivity in the evaluation of the useful efficiency. This model could comprehensively evaluate the energy efficiency of optical communication systems, for improvements of system energy efficiency, and could adapt and promote applications of optical communication systems in new scenarios.

Aiming at the situation of imperfect spectrum sensing of cognitive radio in actual cognitive ultra-dense network sce- narios, this paper proposed a resource allocation scheme based on imperfect spectrum sensing. The target was to maximize the energy efficiency of secondary network in cognitive ultra-dense network with imperfect spectrum sensing while taking into ac- count cross-tier/co-tier interference constraints and ensuring users quality of service. And this paper constructed the energy efficiency optimization problem based on the network model, which was a mixed integer non-convex programming problem, then transformed it into an equivalent convex optimization problem by the time-sharing relaxation method and Dinkelbach me- thod, and finally used the Lagrangian dual method to get its optimal solution, thereby obtained the sub-channel and power allo- cation strategy for optimal energy efficiency. Based on this, this paper proposed an iterative sub-channel and power allocation algorithm. In order to trade off the computational complexity, this paper also proposed a practical sub-channel and power allo- cation algorithm. Simulation results show that the proposed algorithms effectively improve energy efficiency. [ABSTRACT FROM AUTHOR]

Copyright of Study on Optical Communications / Guangtongxin Yanjiu is the property of Study on Optical Communications Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Nanchang University (Engineering & Technology) is the property of Nanchang University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Refrigeration is the property of Journal of Refrigeration Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The green transformation of the manufacturing industry is an important segment in high-quality development, and the vigorous development of the digital economy has provided a new impetus. Taking the balanced panel data of 277 cities in China from 2011 to 2021 as the sample, this study used the super-efficient SBM model containing unexpected output to measure the effects of the green transformation of the manufacturing industry at the city level, measured the digital economy index at the city level based on the entropy weight method, and then used the general nesting spatial model to empirically analyze the impact of the digital economy on the green transformation of the manufacturing industry. After drawing the basic conclusions, this study further applied the mediation effect model and the two-zone spatial econometric model to analyze the mediation and moderation factors of the digital economy on the green transformation of the manufacturing industry. The results indicated that: (1) The green transformation of manufacturing industry among Chinese cities presented a spatial clustering feature, specifically manifested as the siphon effect, which means that the green transformation of manufacturing industry in a city was not conducive to the green transformation of manufacturing industry in its surrounding cities. (2) The digital economy not only significantly promoted the green transformation of the manufacturing industry in this city, but also in the surrounding cities. This conclusion remained valid after a series of endogeneity and robustness tests. (3) Mediation analysis found that the promotion of the digital economy in the green transformation of the manufacturing industry occurred through three channels: promoting green technology innovation, optimizing resource allocation efficiency, and improving green credit. (4) Moderation analysis indicated that the relationship between the digital economy and the green transformation of the manufacturing industry was affected by energy efficiency, and lower energy efficiency weakened the role of the digital economy. Compared to existing research, this study improves the theoretical mechanism of the digital economy-manufacturing green transformation relationship from the perspectives of resources and credit and explores the moderation factors in this relationship from the energy perspective. The spatial econometric model in this study also comprehensively considers the spatial correlation caused by geographical and economic factors, which is progress compared to previous studies that only considered geographical spatial correlation. Based on the research results, this study proposes relevant implications to accelerate the development of the digital economy, improve energy efficiency, accelerate green technology innovation, improve resource allocation efficiency, and optimize green credit. [ABSTRACT FROM AUTHOR]

In addressing the challenge of the multiplicative fading introduced by passive reconfigurable intelligent surface (RIS) in high-speed railway scenarios, an effective solution is the deployment of an active RIS. However, the conventional fully-connected architecture of active RIS, characterized by a multitude of active elements, results in excessive hardware costs and power consumption. Consequently, a sub-connected architecture of active RIS was proposed, with the aim of simultaneously considering the system's energy efficiency and the transmission rate in trainground communication. Initially, a system model for active RIS-assisted multi-user scenarios was established, taking into account the distinctive features of the high-speed railway environment. Subsequently, the problem of maximizing system energy efficiency was formulated by considering constraints on the maximum transmission power of the base station, the transmission power of the active RIS, and the phase-shift matrix of the active RIS. Through the utilization of Lagrange dual transformation and quadratic transformation from fractional programming theory, the non-convex problem was transformed into a convex optimization problem. Finally, an alternating optimization algorithm was proposed for the joint optimization of beamforming and the phase-shift matrix of the active RIS. Simulation results indicate that, compared to traditional passive RIS and fully-connected of active RIS architectures, the proposed solution effectively addresses the multiplicative fading issue. Additionally, the proposed solution achieves higher energy efficiency while meeting user transmission rate requirements [ABSTRACT FROM AUTHOR]

Addressing the optimization problem during the simultaneous energy and information transmission stage in the simultaneous wireless information and power transfer (SWIPT), an optimal energy efficiency strategy based on mmWave cooperative communication small cell is proposed to maximize the link energy efficiency. This strategy, under the joint constraints of minimum link transmission rate and minimum collected energy, employs a power splitting mode at the receding end of energy-constrained user devices. By optimizing transmit power control and power splitting factors, it aims to maximize the systems link energy efficiency. Recognizing the original problem as a nonconvex fractional programming problem with NP-hard characteristics, the Dinkelbach method is utilized to transform the objective function into a convex optimization problem that is easier to solve. An iterative algorithm is designed to find the optimal solution through cross iterations. Simulation results demonstrate that the proposed strategy outperforms traditional power control methods and maximum transmit power approaches in optimizing system energy efficiency. [ABSTRACT FROM AUTHOR]

Copyright of Economic Science / Jingji Kexue is the property of Economic Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To solve the problems of energy limitation, spectrum shortage, and serious co-frequency interference in the unmanned aerial vehicle (UAV)-assisted D2D (device-to-device) communication network under passive eavesdropping, the concept of the network secrecy energy efficiency was introduced by taking into account the secrecy rate and transmit power constraints of each user. Based on the physical layer secure transmission theory, the joint optimization problem of spectrum multiplexing and power control strategies was investigated to maximize the network secrecy energy efficiency. The problem was a nonlinear nonconvex problem, a resource allocation algorithm combining Dinkelbach's algorithm and the convex approximation algorithm was proposed to transform the nonconvex optimization problem into a geometric planning problem through the convex approximation algorithm and ensure that the original problem converges to the global optimal solution by Dinkelbach's algorithm. Simulation results show that the proposed algorithm can effectively mitigate the co-channel interference, improve the network secrecy energy efficiency, and balance the relationship between the secure communication performance and power consumption of the network. [ABSTRACT FROM AUTHOR]

In the face of the high power consumption issue caused by the dense deployment of base stations in cell-free networks, a wideband cell-free network system with sub-connected active reconfigurable intelligent surface (RIS) was proposed. Firstly, based on the constraints of maximum power consumption at the active RIS, amplification factor, and maximum power consumption at the base station, a joint precoding design problem for the base station and RIS was formulated to maximize the energy efficiency. To solve the non-convex problem, advanced techniques including alternating optimization, block coordinate descent, Lagrange dual reconstruction, and multidimensional complex quadratic transformation were applied to transform the original problem into multiple sub-problems. By iteratively solving each sub-problem, the solutions of the original problem was ultimately obtained. The simulation results validate the effectiveness of the proposed scheme. [ABSTRACT FROM AUTHOR]

Copyright of Telecommunications Science is the property of Beijing Xintong Media Co., Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to optimize the energy efficiency and spectral efficiency of decoded-and-forwarded full-duplex relay network in imperfect channel state information, this paper proposed an energy efficiency and spectral efficiency balancing strategy based on this network model. It could replace the non-convex multi-objective optimization problem to a convex single-objective optimization problem by constructing a compromise optimization function of energy efficiency and spectral efficiency. It used derivation method and Lagrange multiplier method to solve the optimal relay transmission power under different compromise factors. The simulation results show that changing the compromise factor can change the energy efficiency and spectral effectiveness of the system and obtain the performance tradeoff of energy efficiency and spectrum effectiveness. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Electrochemistry is the property of Journal of Electrochemistry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Refrigeration is the property of Journal of Refrigeration Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Refrigeration Technology is the property of Shanghai Society of Refrigeration and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Agricultural machinery is ever-increasingly either displacing or augmenting human labor with the development of the economy and technology. Among them, fuel efficiency has a significant impact on energy conservation and emission reduction, indicating high economic and social significance. Particularly, a tractor is one of the most typical agricultural machinery. In this study, the overall energy efficiency of tractors was evaluated under actual operating conditions. The performance of tractors was also measured comprehensively. The actual energy efficiency of tractors was clearly defined and calculated as well. The common operating points of tractor engines were extracted by K-means clustering and pairwise comparison matrix, according to the shortest distance partition. The energy efficiency of 186 162 kW tractors was analyzed to propose the classification standard using tractor energy efficiency. Energy efficiency limits and energy efficiency ratio limits were determined at all levels. The average energy efficiency was compared using different operating links. The results showed that there was a significant difference in the distribution and weight between the actual eight operating points and the ISO steady-state eight operating points. The main reason was that the ISO steady-state eight operating point was targeted at nonroad diesel engines, covering a wide range of engine models, power, and applications. However, the actual eight operating points were more specific, and refined for the actual operating conditions of multiple 162 kW tractor engines. The error range of tractor energy efficiency was −0.483-0.487 (kW·h)/kg using two datasets of working conditions. Therefore, the energy efficiency calculation was necessary and meaningful using the actual eight working conditions. In addition, there was a significant difference in the tractor energy efficiency using actual operating conditions, where 50% of tractor energy efficiency values were distributed in the range of 3.20 to 3.65 (kW·h)/kg, with an average value of 3.42 (kW·h)/kg. This difference was attributed to the driving habits of agricultural machinery operators, the tractor maintenance and repair levels, as well as the tractor age, resulting in the varying degrees of reduction in engine performance indicators. Then, the grading was constructed using the tractor energy efficiency, where 3.07 (kW·h)/kg was determined as the qualification limit of actual energy efficiency in the tractor. The limit values were also determined for the tractor energy efficiency ratio for levels 1-4. As such, the classification of energy efficiency levels was achieved for tractors. There was a significant variation in the average energy efficiency at different operation stages of each tractor. The rotary tillage mode presented the highest value of average energy efficiency, whereas, the walking mode was the lowest. The trend was attributed to the different engine loads of tractors at different operating stages. Therefore, there was great potential for the real-world energy efficiency performance of tractors from a user perspective. The actual operating performance of tractors was explored to establish an evaluation system applicable to the energy efficiency performance of tractors in the real world. The findings can provide the basic data for energy-saving and emission reduction in tractor engines. A strong reference can be also offered to assess the energy efficiency of agricultural machinery on application subsidy suitable for the level of green operation. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Data Acquisition & Processing / Shu Ju Cai Ji Yu Chu Li is the property of Editorial Department of Journal of Nanjing University of Aeronautics & Astronautics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Beijing University of Technology is the property of Journal of Beijing University of Technology, Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Xinyang Normal University Natural Science Edition is the property of Journal of Xinyang Normal University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] Energy efficiency improvement is an effective means to increase the synergy between economic development and energy conservation and emission reduction. In this study, the effects of market integration on regional energy efficiency and mechanisms were examined to provide a theoretical support and policy reference for efficiency improvement of China’s unified large market construction policy. [Methods] The stochastic frontier analysis (SFA) model was used to measure the energy efficiency of 239 prefecture-level cities in China from 2006 to 2019, and the growth of energy efficiency was decomposed into three aspects: technological progress, technical efficiency change, and scale efficiency change; the panel fixed effect and mediation effect models were used to analyze the effect of market integration on regional energy efficiency, heterogeneity, and mechanism. [Results] The study found that: (1) Market integration can effectively promote regional energy efficiency, and the improvement of scale efficiency and technological progress are the key paths of market integration improving energy efficiency. (2) Market integration is more likely to improve energy efficiency in regions with high innovation levels and high population densities, and for regions with weaker innovation bases and lower population densities, the development of market integration can take the lead in improving regional scale efficiency and technological progress. (3) Market integration is more likely to improve regional energy efficiency by promoting the agglomeration of productive services. (4) Market integration can help alleviate the disparity of energy efficiency between regions. [Conclusion] The construction of a large national unified market to promote regional market integration is conducive to the effect of regional scale efficiency and technological progress, which in turn improves regional energy efficiency and promotes effective synergy between economic development and energy conservation and emission reduction.

Copyright of Journal of Refrigeration is the property of Journal of Refrigeration Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Telecommunication Engineering is the property of Telecommunication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Exploring the green economic effects of digital economy development from the dual perspective of reducing urban pollution emissions and improving urban energy efficiency is in line with the requirements of the times for a Chinese path to modernization. This study analyzed the spatial and temporal patterns of digital economy development in China based on panel data from 280 Chinese cities at the prefecture level and above from 2011 to 2019 using ArcGIS spatial analysis and adopted the fixed effects model, the difference-indifferences model, and the spatial Durbin model to test the ‘emission reduction’ and ‘efficiency enhancement’ effects of digital economy development. The results showed that: ① China’ s digital economy development as a whole showed an incremental trend, and the regional development gap was narrowing. In terms of spatial evolution pattern, the development pattern of advance zones evolved from sporadic distribution to multi-point coverage, and the number of promotion areas distributed around the advance areas gradually increased, forming a group development pattern with the advance areas. ② The development of the digital economy was conducive to reducing about 4% of urban pollution emissions and improving about 9% of urban energy efficiency, and this conclusion still held after a series of robustness tests and endogeneity discussions. ③ The impact of digital economy development on ‘emission reduction’ and ‘efficiency enhancement’ differed by geographical location, administrative level, and resource endowment. Among them, the digital economy development in the eastern region only enhanced efficiency but did not reduce emissions, while the digital economy development in non-eastern regions, central cities, and non-resource-based cities both reduced emissions and enhanced efficiency. ④ Industrial structure upgrading was the intermediary mechanism for ‘emission reduction’ and ‘efficiency enhancement’ of digital economy development, while human capital was only the intermediary mechanism for ‘efficiency enhancement’ of digital economy development. ⑤ The digital economy development was conducive to ‘emission reduction’ and ‘efficiency enhancement’ in a region, but through the spatial spillover effect on neighboring regions, only ‘efficiency enhancement,’ not ‘emission reduction’ was achieved. This study suggests that we should continue to strengthen the foundation of digital economy development. While being alert to the development gap between regions, we should try to improve the data element resource system, focus on cultivating versatile talents, and promote the transformation and upgrading of traditional industries, so as to help the region form a synergy for digital economy development and achieve the ‘winwin’ goal of reducing pollution emissions and improving energy efficiency for the whole society. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Chongqing University of Technology (Natural Science) is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Data Acquisition & Processing / Shu Ju Cai Ji Yu Chu Li is the property of Editorial Department of Journal of Nanjing University of Aeronautics & Astronautics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Rural Water & Hydropower is the property of China Rural Water & Hydropower Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Refrigeration is the property of Journal of Refrigeration Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An energy efficiency optimization transmission scheme using angular information-based channel state in-formation (AI-CSI) was proposed for indoor communications, which integrated the power line communication (PLC) with radio frequency (RF) wireless communication. Specifically, by considering that the Wi-Fi wireless network and the PLC network were the primary and secondary networks, an optimization problem was established to maximize the total energy efficiency of the secondary network. Then, in order to solve the problem, the beam forming weight vector was obtained by using zero-forcing method based on AI-CSI, and an optimization algorithm joint Dinkelbach with Lagrange multiplier was further presented to achieve the optimal power allocation. Finally, computer simulations were given to verify the effectiveness and superiority of the proposed scheme. Besides, the influence of key parameters such as the number of employed antennas and served users was also analyzed. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Refrigeration Technology is the property of Shanghai Society of Refrigeration and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Extract residue of coal liquefaction residue (ERCLR) is a solid mixture of high carbon, high ash, high sulfur, and complex composition, mainly including unconverted coal, inorganic minerals, and coal liquefaction catalyst. The effective use of ERCLR, which has high utilization value based on high hydrogen-to-carbon ratio, not only improves the thermal efficiency and economy of coal liquefaction process, but also reduces the emissions of pollutants. The energy efficiency analysis, environmental impact, and economic analysis of three power generation systems were calculated and analyzed by Aspen Plus. The three power generation systems are ERCLR gasification combined cycle power generation system, ERCLR combustion power generation system, and ERCLR pyrolysis combustion power generation system. The results show that the energy efficiency of ERCLR gasification combined cycle power generation system is 47.5%, which is better than that of ERCLR combustion power generation system (43%) and ERCLR pyrolysis combustion power generation system (45.3%). The flue gas emission of ERCLR gasification combined cycle power generation system has lower impact on environment than that of the other two systems. ERCLR gasification combined cycle power generation system provides a lower cost of electricity (0.44 CNY/kWh), compared with ERCLR combustion power generation system (0.48 CNY/kWh) and ERCLR pyrolysis combustion power generation system (0.69 CNY/kWh). Therefore, ERCLR gasification combined cycle power generation system has significant advantages over the other two utilization approaches. For the recovery and utilization of ERCLR, ERCLR gasification combined cycle can be given priority to power generation.

In the case of finite alphabet inputs, information transmission rate limit of orthogonal frequency division multiplexing (OFDM) visible light communications (VLC) and radio frequency (RF) aggregation systems is still unknown. Therefore, the unclosed expression information transmission rate and its lower bound with closed expression of OFDM VLC-RF aggregation system are derived based on mutual imformation function, and the problem of energy efficiency maximization is studied based on the two communication rates. Specifically, the energy efficiency maximization problem satisfying the spectrum efficiency (SE) threshold, total electric power and average optical power constraints is studied. At the same time, the Dinkelbach-type algorithm is used to transform the energy efficiency maximization nonconvex problem into a series of convex sub-problems, and then the interior point algorithm is used to solve it. Simulation results show that when SE threshold increases, energy efficiency first remains constant and then decreases, and energy efficiency based on the lower bound of information transmission rate can be used as a low complexity approximation of energy efficiency based on information transmission rate. The finite alphabet inputs VLC-RF aggregation system studied in this paper provides a new direction for practical communication aggregation system research.

Copyright of Telecommunications Science is the property of Beijing Xintong Media Co., Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In MEC combining IRS and resource allocation strategies to improve system energy efficiency is a current hot topic of research at home and abroad. This paper aimed to maximize energy efficiency in IRS-assisted MEC system through joint optimization of the computing frequency at users, transmit power and time, and the IRS discrete phase-shift based on the transmission mode of hybrid non-orthogonal multiple access. Since the optimization process involved non-convex fractional programming problems that are difficult to solve, this paper proposed a Dinkelbach-SCA algorithm with two iterative-steps. Firstly, this paper converted the initial problem into a tractable form via Dinkelbach' s method, optimization of IRS discrete phase shift by separating variables. Then, by introducing auxiliary variables, and leveraging successive convex approximation, the paper decoupled the relationship between transmit power and time while converted the non-convex problem to a convex one. Hence, the paper could obtain optimal solution. The simulation results show that the energy efficiency of the proposed system scheme is better than other comparison ones, and the energy efficiency of the system increases with the decrease of the minimum computational data amount of user 2. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Chongqing University of Posts & Telecommunications (Natural Science Edition) is the property of Chongqing University of Posts & Telecommunications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to promote China′s energy conservation and emission reduction and advance high-quality economic development, this paper analyzed the relationship between green technology innovation and energy efficiency in China′s coastal areas, empirical test the internal transmission mechanism between them through intermediary variables, and put forward countermeasures and suggestions. The results showed that green technology innovation could improve energy efficiency, but there was a threshold effect between them. When the threshold was crossed, the effect of green technology innovation on energy efficiency was weakened. Industrial structure, urbanization level and informatization level were the intermediary transmission factors of green technology innovation to improve energy efficiency. In the future, China should further improve the top-level design of ecological civilization, optimize the industrial structure and layout, reasonably control the scale of cities and towns and population, and drive the development of industrialization with informatization.

Copyright of Telecommunication Engineering is the property of Telecommunication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The energy-consuming right trading system is a market-oriented environmental regulation policy based on source control in China, the implementation of which aims to help the realization of the goal of controlling total energy consumption and energy intensity and to promote green development. Based on the panel data of prefecture-level cities from 2012 to 2019, this article theoretically analyzed the mechanism of the action of the energy-consuming right trading system; applied the multi-period PSM-DID method to empirically test whether the energy-consuming right trading system had achieved win-win development for both the environment and the economy; and tested the robustness of the findings by replacing variable settings, adding control variables, and applying placebo tests. In addition, the short-term and long-term impact paths of the environmental and economic effects of the energy-consuming right trading system are theoretically analyzed and empirically tested respectively. The findings were as follows: (1) The implementation of the energy-consuming right trading system effectively reduced the total emission and emission intensity of energy pollutants and realized positive benefit for the environment. Besides, the reduction in emission intensity was more significant. (2) The energy-consuming right trading system not only increased the quantity of economic development, but also pulled up the economic growth rate, thus realizing a positive benefit to the economy. (3) The results of the dynamic effect analysis showed that the energy-consuming right trading system did not have a persistent effect on the total amount and intensity of pollution emissions. But it had a more significant and persistent effect on the rate and level of economic development. (4) Since the energy-consuming right trading system was in the early pilot stage, it mainly achieved environmental and economic dividends through the short-term path of improving energy efficiency and not the long-term path of industrial structure upgrading or energy structure adjustment. Based on this, we should further build and improve the energy-consuming right trading market and improve the design of the system to ensure standardization, convenience, and transparency during the operation and enhance the degree of marketization. It is also of great importance to accelerate the development of new energy, new technologies, and new industries to promote green transformation and decarbonization in the energy industry. Furthermore, we should build a comprehensive and coordinated environmental policy system by promoting the coordinated implementation of the energy-consuming right trading system with other environmental regulation policies based on emission control, realizing the benefits of ' 1 + 1 >2.' [ABSTRACT FROM AUTHOR]

Copyright of Journal of Data Acquisition & Processing / Shu Ju Cai Ji Yu Chu Li is the property of Editorial Department of Journal of Nanjing University of Aeronautics & Astronautics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bulletin of the Chinese Ceramic Society is the property of Bulletin of the Chinese Ceramic Society Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

5G network is considered as enabler for Smart Grids (SG). However, it is inefficient and costly to travel over large area and penetrate physical blind area in SG. The significant improvement in this work is proposing 5G loRa converged network to offer a seamless, large scale, zero wiring, and real-time IoT monitoring strategy. On the basis of this framework, multiple LoRa Ad-Hoc network can coalesce with the 5G SG network via 5G LoRa intelligent gateway. Experiments and tests in real scenarios demenstrate that the proposed 5G LoRa Ad-Hoc networking enables the achievement of communication blind and wide-area SG IoT monitoring. The collection of information is accurate and the system runs stably. By introducing Charnes-Cooper transform and Lagrange Multiplier iteration algorithm, the resource allocation problem is formulated as a mixed integer relaxation optimization, aiming to maximize the sum energy efficiency of multi-hop LoRa. Simulation results unveil that the optimal number of active LoRa nodes and resource allocation in each cluster exists to maximize the area energy efficiency. Analysis also validates the existing ultimate efficiency of our proposed model, which is 6.2 times higher than that of static benchmark algorithms in terms of energy efficiency and QoS requirements.

Copyright of Telecommunication Engineering is the property of Telecommunication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The fused filament fabrication 3D printing energy efficiency was predated and optimized based on response surface method and support vector regression model. Firstly, the Taguchi method was used to design the six factor three level orthogonal test, based on the response surface method, three factors that had a significant impact on processing energy efficiency were obtained, namely layer height, printing speed and hot bed temperature. Then, the prediction model of processing energy efficiency was established by support vector regression method, and compared with BP neural network method, the results show that the modeling and prediction performance of support vector regression method Is better. Finally, the optimization model aiming at processing time and energy efficiency was established, and NSGA-II, MOEA/D, SPEA2 and MOPSO were used to solve the model respectively, the Pareto front of the four algorithms was analyzed and compared, the results show that NSGA-II performs best in solving this problem, the optimization results obtained by NSGA-II algorithm were compared with the experimental results, which reflects the effectiveness and rationally of the optimization results of NSGA-II algorithm. [ABSTRACT FROM AUTHOR]

The energy efficiency of wireless networks has gradually become an important indicator for evaluating network performance. It's very important to improve the energy efficiency of the coexisting 4G and 5G networks as there are differences in energy efficiency of them. Firstly, the energy consumption composition of base station was analyzed, energy consumption models for 4G and 5G base stations through measured data were established, and then its energy efficiency was evaluated through simulations. The results show that 4G and 5G have their own optimal energy-efficiency areas separated by the critical point of 500 Mbit/s, above which the 5G energy efficiency is better. When dual networks operate simultaneously under the proposed-solution where only 4G is used when the throughput is less than 500 Mbit/s and only 5G is used otherwise, the power consumption of a single station can be reduced by 53.4% and the energy efficiency can be improved by 116.4%. [ABSTRACT FROM AUTHOR]