CsPbX_(3)-based(X=I,Br,Cl)inorganic perovskite solar cells(PSCs)prepared by low-temperature process have attracted much attention because of their low cost and excellent thermal stability.However,the high trap state d...CsPbX_(3)-based(X=I,Br,Cl)inorganic perovskite solar cells(PSCs)prepared by low-temperature process have attracted much attention because of their low cost and excellent thermal stability.However,the high trap state density and serious charge recombination between low-temperature processed TiO_(2)film and inorganic perovskite layer interface seriously restrict the performance of all-inorganic PSCs.Here a thin polyethylene oxide(PEO)layer is employed to modify TiO_(2)film to passivate traps and promote carrier collection.The impacts of PEO layer on microstructure and photoelectric characteristics of TiO_(2)film and related devices are systematically studied.Characterization results suggest that PEO modification can reduce the surface roughness of TiO_(2)film,decrease its average surface potential,and passivate trap states.At optimal conditions,the champion efficiency of CsPbI_(2)Br PSCs with PEO-modified TiO_(2)(PEO-PSCs)has been improved to 11.24%from 9.03%of reference PSCs.Moreover,the hysteresis behavior and charge recombination have been suppressed in PEO-PSCs.展开更多
Micromixing efficiency is an important parameter for evaluating the multiphase mass transfer performance and reaction efficiency of microreactors.In this work,the novel curved capillary reactor with different shapes w...Micromixing efficiency is an important parameter for evaluating the multiphase mass transfer performance and reaction efficiency of microreactors.In this work,the novel curved capillary reactor with different shapes was designed to generate Dean flow,which was used to enhance the liquid-liquid micromixing performance.The Villermaux-Dushman probe reaction was employed to characterize the micromixing performance in different curved capillary microreactors.The effects of experiment parameters such as liquid flow rate,inner diameter,tube length,and curve diameter on micromixing performance were systematically investigated.Under the optimal conditions,the minimum value of the segmentation factor XS was 0.008.It was worth noting that at the low Reynolds number(Re<30),the change of curved shape on the capillary microreactor can significantly improve the micromixing performance with XS reduced by 37.5%.Further,the correlations of segment index XS with dimensionless factor such as Reynolds number or Dean number were developed,which can be used to predict the liquid-liquid micromixing performance in capillary microreactors.展开更多
In China,the oversupply of coal occurred in 2009,and from that year onwards,China’s coal economy began a low-carbon and clean transformation.Evaluating transformation performance is the research goal of this paper.Th...In China,the oversupply of coal occurred in 2009,and from that year onwards,China’s coal economy began a low-carbon and clean transformation.Evaluating transformation performance is the research goal of this paper.The data collection for this paper includes data on deep processing of Chinese coal products from 2009 to 2020,as well as data on asset structure evolution and financial performance of 34 listed companies in the Chinese coal mining.Entropy value method is used to calculate the entropy value of low-carbon transformation,and the regression analysis is used to study the performance of cleaner transformation,the conclusion is as follows:(1)From 2009 to 2020,in China’s total energy consumption,coal consumption accounted for 71.6%in 2009 and 56.8%in 2020,the goals set by the state have been achieved.(2)The national goal of reducing the proportion of coal consumption and reducing carbon emissions has forced the transformation of deep processing of coal products.The transformation of coal enterprises towards low-carbon and clean production has achieved remarkable results.(3)From 2009 to 2020,the non coal industry income of 34 listed companies in China’s coal mining industry increased by 8.21%annually.At the same time,the asset structure was adjusted,and nearly 80%of the asset structure evolution showed an orderly development trend.(4)The regression analysis results show that the entropy value of coal deep processing products and the entropy value of asset structure adjustment are significantly related to transformation performance.The paper proposes to summarize the successful experience of China’s coal energy economic transformation,lay a foundation for achieving the carbon peak and carbon neutral goals in the future,further increase the intensity of coal deep processing,increase the proportion of clean energy in total energy consumption,and strive to control asset operation towards the goal of increasing the proportion of non coal industry income.展开更多
The Mixed Refrigerant(MR)component is an important factor influencing the performances of natural gas lique-faction processes.However,there is a lack of systematic research about the utilization of propane pre-cooled(...The Mixed Refrigerant(MR)component is an important factor influencing the performances of natural gas lique-faction processes.However,there is a lack of systematic research about the utilization of propane pre-cooled(C3/MRC).In this paper,this mixed refrigerant cycle liquefaction process is simulated using the HYSYS software and the main influential parameters involved in the process are varied to analyze their influence on the liquefaction rate and power consumption.The results show that an effective way for lowering the power consumption of the compressor consists of reducing the flow through the compressor through optimization of the percentage of mixed refrigerant.The power consumption of the compressor in the hybrid refrigeration process is affected by both flow and pressure ratios.Its specific power consumption can be reduced by increasing the flow and decreasing the pressure ratio at the same time.The increase in refrigerant pressure at the high-pressure end can significantly mitigate the energy loss of the heat exchanger and compressor.展开更多
A set of indices for performance evaluation for business processes with multiple inputs and multiple outputs is proposed, which are found in machinery manufacturers. Based on the traditional methods of data envelopmen...A set of indices for performance evaluation for business processes with multiple inputs and multiple outputs is proposed, which are found in machinery manufacturers. Based on the traditional methods of data envelopment analysis (DEA) and analytical hierarchical process (AHP), a hybrid model called DEA/AHP model is proposed to deal with the evaluation of business process performance. With the proposed method, the DEA is firstly used to develop a pairwise comparison matrix, and then the AHP is applied to evaluate the performance of business process using the pairwise comparison matrix. The significant advantage of this hybrid model is the use of objective data instead of subjective human judgment for performance evaluation. In the case study, a project of business process reengineering (BPR) with a hydraulic machinery manufacturer is used to demonstrate the effectiveness of the DEA/AHP model.展开更多
Solidification processes of Al7SiMg-xY(0.1wt%,0.3wt%,0.5wt%) alloys were investigated by thermal analysis.The microstructures were observed by using optical microscopy and scanning electron microscopy.Effects of diffe...Solidification processes of Al7SiMg-xY(0.1wt%,0.3wt%,0.5wt%) alloys were investigated by thermal analysis.The microstructures were observed by using optical microscopy and scanning electron microscopy.Effects of different concentrations of yttrium on tensile performance both as cast and T6 heat treated were studied at room temperature,respectively.The results show that little changes happen in liquidus with increases concentration of yttrium.While it results in obvious depression of solidus and eutectic arrest temperature in solidification process.Moreover,the solidification range increases significantly.The performance is better when concentration of yttrium is 0.1wt%.With increment of yttrium,more large flake-like compounds of yttrium gather in grain boundaries,performance especially the elongation of the alloy decrease remarkably.展开更多
To solve the critical problems of lithium rich cathode materials, e.g., structure instability and short cycle life, we have successfully prepared a ZrO2-coated and Zr-doping xLi2MnO3·(1–x)LiMO2 hollow architectu...To solve the critical problems of lithium rich cathode materials, e.g., structure instability and short cycle life, we have successfully prepared a ZrO2-coated and Zr-doping xLi2MnO3·(1–x)LiMO2 hollow architecture via one-time sintering process. The modified structural materials as lithium-ion cathodes present good structural stability and superior cycle performance in LIBs. The discharge capacity of the ZrO2-coated and Zr-doped hollow pristine is 220 mAh g-1 at the 20th cycle at 0.2 C(discharge capacity loss, 2.7%)and 150 m Ah g-1 at the 100 th cycle at 1 C(discharge capacity loss, 17.7%), respectively. However, hollow pristine electrode only delivers 203 m Ah g-1 at the 20 th cycle at 0.2 C and 124 mAh g-1 at the 100 th cycle at 1 C, respectively, and the corresponding to capacity retention is 92.2% and 72.8%, respectively.Diffusion coefficients of modified hollow pristine electrode are much higher than that of hollow pristine electrode after 100 cycles(approach to 1.4 times). In addition, we simulate the adsorption reaction of HF on the surface of ZrO2-coated layer by the first-principles theory. The calculations prove that the adsorption energy of HF on the surface of ZrO2-coated layer is about-1.699 e V, and the ZrO2-coated layer could protect the hollow spherical xLi2MnO3·(1–x)LiMO2 from erosion by HF. Our results would be applicable for systematic amelioration of high-performance lithium rich material for anode with the respect of practical application.展开更多
This paper selected the corn processing industry technology innovation alliance in Heilongjiang Province as the research object, evaluated the operational performance of the alliance by using analytic hierarchy proces...This paper selected the corn processing industry technology innovation alliance in Heilongjiang Province as the research object, evaluated the operational performance of the alliance by using analytic hierarchy process(AHP) and fuzzy comprehensive evaluation methods. AHP empirical results showed that the satisfaction of information communication and the satisfaction of the management process were the weakest. And the order from high to low on the level of indicators of the impact for the alliance was the result of alliance operations and the process of alliance operations, the behavioral attitude of alliance members. Besides, the results of fuzzy comprehensive evaluation showed that the operational performance of the corn processing industry technology innovation alliance in Heilongjiang Province was in the general level.展开更多
The doping process and thermoelectric properties of donor-acceptor(D-A)type copolymers are investigated with the representative poly([2,6-4,8-di(5-ethylhexylthienyl)benzo[1,2-b;3,3-b]dithiophene]3-fluoro-2-[(2-ethylhe...The doping process and thermoelectric properties of donor-acceptor(D-A)type copolymers are investigated with the representative poly([2,6-4,8-di(5-ethylhexylthienyl)benzo[1,2-b;3,3-b]dithiophene]3-fluoro-2-[(2-ethylhexyl)-carbonyl]thieno[3,4-b]thiophenediyl))(PTB7-Th).The PTB7-Th is doped by Fe Cl;and only polarons are induced in its doped films.The results reveal that the electron-rich donor units within PTB7-Th lose electrons preferentially at the initial stage of the oxidation and then the acceptor units begin to be oxidized at a high doping concentration.The energy levels of polarons and the Fermi level of the doped PTB7-Th remain almost unchange with different doping levels.However,the morphology of the PTB7-Th films could be deteriorated as the doping levels are improved,which is one of the main reasons for the decrease of electrical conductivity at the later stage of doping.The best electrical conductivity and power factor are obtained to be 42.3 S·cm^(-1);and 33.9μW·mK^(-1),respectively,in the doped PTB7-Th film at room temperature.The power factor is further improved to 38.3μW·mK^(-1);at 75℃.This work may provide meaningful experience for development of D-A type thermoelectric copolymers and may further improve the doping efficiency.展开更多
In recent years, the widespread adoption of parallel computing, especially in multi-core processors and high-performance computing environments, ushered in a new era of efficiency and speed. This trend was particularl...In recent years, the widespread adoption of parallel computing, especially in multi-core processors and high-performance computing environments, ushered in a new era of efficiency and speed. This trend was particularly noteworthy in the field of image processing, which witnessed significant advancements. This parallel computing project explored the field of parallel image processing, with a focus on the grayscale conversion of colorful images. Our approach involved integrating OpenMP into our framework for parallelization to execute a critical image processing task: grayscale conversion. By using OpenMP, we strategically enhanced the overall performance of the conversion process by distributing the workload across multiple threads. The primary objectives of our project revolved around optimizing computation time and improving overall efficiency, particularly in the task of grayscale conversion of colorful images. Utilizing OpenMP for concurrent processing across multiple cores significantly reduced execution times through the effective distribution of tasks among these cores. The speedup values for various image sizes highlighted the efficacy of parallel processing, especially for large images. However, a detailed examination revealed a potential decline in parallelization efficiency with an increasing number of cores. This underscored the importance of a carefully optimized parallelization strategy, considering factors like load balancing and minimizing communication overhead. Despite challenges, the overall scalability and efficiency achieved with parallel image processing underscored OpenMP’s effectiveness in accelerating image manipulation tasks.展开更多
[Objective] The paper was to compare the effects of traditional granulating process and post-expanding lower temperature granulating process on starch gelatinization degree and in vitro protein digestibility of conver...[Objective] The paper was to compare the effects of traditional granulating process and post-expanding lower temperature granulating process on starch gelatinization degree and in vitro protein digestibility of conversation feed, and growth performance of piglets. [Method] Sixty weaned piglets, 25 days old, were randomly divided into two groups, six replicates each group, and each replicate contained five piglets. Piglets in control group were fed with the conversation feed developed by traditional granulating process, and those in experimental group were fed with the conservation feed developed by post-expanding lower temperature granulating process. The trial lasted 28 d. [Result] Compared to traditional granulating process, post-expanding lower temperature granulating process significantly enhanced starch gelatinization degree of conservation feed by56.9%(P〈0.05), and significantly improved in vitro protein digestibility of conservation feed by 11.48%(P〈0.05). Compared to the control group, the feed intake of piglets in experimental group was increased by 21.63%(P〈0.05); the average daily gain was increased by 27.61%(P〈0.05); the diarrhea rate was lowered; and the feed gain ratio was improved by 4.51%(P〉0.05). The results suggested that post-expanding lower temperature granulating process effectively enhanced feed digestion and absorption of piglets. [Conclusion] The paper provides a theoretical basis and practical reference for improvement of production process of conservation feed.展开更多
Evaluating performance of individual features of WiMAX technology is a topic of widespread discussion. Currently, there is no quantitative way of measuring WiMAX technology so that wireless operators can meet their de...Evaluating performance of individual features of WiMAX technology is a topic of widespread discussion. Currently, there is no quantitative way of measuring WiMAX technology so that wireless operators can meet their design objectives. This paper outlines a set of design criteria for WiMAX and provides a decision-making aid that ranks the importance of criteria using Analytic Hierarchy Process (AHP). This ranking should sufficiently reflect market expectations of the relative importance of various design criteria. A model integrating AHP priorities with enhanced Data Envelopment Analysis (DEA) is the basis for formulating a technological value in simple, comparable format. A case study is provided to show how this technological value is used to evaluate a three year network deployment plan. In the future, this model could be extended to WiMAX equipment suppliers for the purpose of validating performance targets of individual criteria, and enhancing supplier roadmaps for future network development.展开更多
It is acknowledged that lacking of interdisciplinary communication amongst designers can result in poor coordination performance in building design. Viewing communication as information processing activity, this paper...It is acknowledged that lacking of interdisciplinary communication amongst designers can result in poor coordination performance in building design. Viewing communication as information processing activity, this paper aims to explore the relationship between interdisciplinary information processing (IP) and design coordination performance. Both amount and quality are concerned regarding information processing. 698 project based samples are collected by questionnaire survey from design institutes in China's Mainland. Statistical data analysis shows that the relationship between information processing amount and design coordination performance follows a nonlinear exponential expression: performance = 3.691 (1-0.235IP amount) rather than reverted U curve. It implies that design period is too short to allow information overload. It indicates that the main problem in interdisciplinary communication in design institute in China is insufficient information. In additional, it is found the correlation between IP quality and coordination process performance is much stronger than that between IP amount and coordination process performance. For practitioners, it reminds design mangers to pay more attention to information processing quality rather than amount.展开更多
Based on the analysis of the common limitations of business processmanagement (BPM) methodologies and the requirements of small and medium sized-enterprises (SMEs),the importance of a 'performance construct' o...Based on the analysis of the common limitations of business processmanagement (BPM) methodologies and the requirements of small and medium sized-enterprises (SMEs),the importance of a 'performance construct' of BPM methodologies is identified, a six-phaseperformance-driven BPM methodology for the production and operation processes of Chinese SMEs isdeveloped. A case study on the process management of a medium-sized enterprise shows a successfulexample of running the methodology.展开更多
Some statistical characteristics of signal and noise in shallow-water acoustical channel were analysed . Based on the differences in some statistical characteristics between the signal and the noise , the authors deve...Some statistical characteristics of signal and noise in shallow-water acoustical channel were analysed . Based on the differences in some statistical characteristics between the signal and the noise , the authors developed a new kind of signal processing technique-digital time correlative accumulation to operate sonar systems at a low data rate . Theoretical analyses and expermental results show . the false-alarm probability can be reduced to a low value of less than 10 -4 while the detection probability can reach a relatively high value of more than 0.9. By using the statistical averages of the multiple range detection value , the authors can greatly improve the accuracy of the detection . The method can be used for some other related fields, for example , ultrasonic detection in air medium .展开更多
Graph processing has been widely used in many scenarios,from scientific computing to artificial intelligence.Graph processing exhibits irregular computational parallelism and random memory accesses,unlike traditional ...Graph processing has been widely used in many scenarios,from scientific computing to artificial intelligence.Graph processing exhibits irregular computational parallelism and random memory accesses,unlike traditional workloads.Therefore,running graph processing workloads on conventional architectures(e.g.,CPUs and GPUs)often shows a significantly low compute-memory ratio with few performance benefits,which can be,in many cases,even slower than a specialized single-thread graph algorithm.While domain-specific hardware designs are essential for graph processing,it is still challenging to transform the hardware capability to performance boost without coupled software codesigns.This article presents a graph processing ecosystem from hardware to software.We start by introducing a series of hardware accelerators as the foundation of this ecosystem.Subsequently,the codesigned parallel graph systems and their distributed techniques are presented to support graph applications.Finally,we introduce our efforts on novel graph applications and hardware architectures.Extensive results show that various graph applications can be efficiently accelerated in this graph processing ecosystem.展开更多
Steels are widely used as structural materials,making them essential for supporting our lives and industries.However,further improving the comprehensive properties of steel through traditional trial-and-error methods ...Steels are widely used as structural materials,making them essential for supporting our lives and industries.However,further improving the comprehensive properties of steel through traditional trial-and-error methods becomes challenging due to the continuous development and numerous processing parameters involved in steel production.To address this challenge,the application of machine learning methods becomes crucial in establishing complex relationships between manufacturing processes and steel performance.This review begins with a general overview of machine learning methods and subsequently introduces various performance predictions in steel materials.The classification of performance pre-diction was used to assess the current application of machine learning model-assisted design.Several important issues,such as data source and characteristics,intermediate features,algorithm optimization,key feature analysis,and the role of environmental factors,were summarized and analyzed.These insights will be beneficial and enlightening to future research endeavors in this field.展开更多
We introduce a new type of robust forward criterion under model uncertainty,called the G-forward performance process,which extends the classical notion of forward performance process to the G-expectation framework.We ...We introduce a new type of robust forward criterion under model uncertainty,called the G-forward performance process,which extends the classical notion of forward performance process to the G-expectation framework.We then derive the representations of homothetic G-forward performance processes in a single stochastic factor model with uncertainty,building on the well-posedness of ergodic and infinite horizon backward stochastic differential equations driven by G-Brownian motion(G-BSDEs)with quadratic generators.展开更多
An alpha-uniformized Markov chain is defined by the concept of equivalent infinitesimalgenerator for a semi-Markov decision process (SMDP) with both average- and discounted-criteria.According to the relations of their...An alpha-uniformized Markov chain is defined by the concept of equivalent infinitesimalgenerator for a semi-Markov decision process (SMDP) with both average- and discounted-criteria.According to the relations of their performance measures and performance potentials, the optimiza-tion of an SMDP can be realized by simulating the chain. For the critic model of neuro-dynamicprogramming (NDP), a neuro-policy iteration (NPI) algorithm is presented, and the performanceerror bound is shown as there are approximate error and improvement error in each iteration step.The obtained results may be extended to Markov systems, and have much applicability. Finally, anumerical example is provided.展开更多
基金financially supported by the Guangzhou Basic and Applied Basic Research Foundation,China(No.303523)。
文摘CsPbX_(3)-based(X=I,Br,Cl)inorganic perovskite solar cells(PSCs)prepared by low-temperature process have attracted much attention because of their low cost and excellent thermal stability.However,the high trap state density and serious charge recombination between low-temperature processed TiO_(2)film and inorganic perovskite layer interface seriously restrict the performance of all-inorganic PSCs.Here a thin polyethylene oxide(PEO)layer is employed to modify TiO_(2)film to passivate traps and promote carrier collection.The impacts of PEO layer on microstructure and photoelectric characteristics of TiO_(2)film and related devices are systematically studied.Characterization results suggest that PEO modification can reduce the surface roughness of TiO_(2)film,decrease its average surface potential,and passivate trap states.At optimal conditions,the champion efficiency of CsPbI_(2)Br PSCs with PEO-modified TiO_(2)(PEO-PSCs)has been improved to 11.24%from 9.03%of reference PSCs.Moreover,the hysteresis behavior and charge recombination have been suppressed in PEO-PSCs.
基金supports of National Natural Science Foundation of China(22308057)Outstanding Talent Introduction Funds from Fuzhou University(0040-511175)Fuzhou University Testing Fund of precious apparatus(2023T003).
文摘Micromixing efficiency is an important parameter for evaluating the multiphase mass transfer performance and reaction efficiency of microreactors.In this work,the novel curved capillary reactor with different shapes was designed to generate Dean flow,which was used to enhance the liquid-liquid micromixing performance.The Villermaux-Dushman probe reaction was employed to characterize the micromixing performance in different curved capillary microreactors.The effects of experiment parameters such as liquid flow rate,inner diameter,tube length,and curve diameter on micromixing performance were systematically investigated.Under the optimal conditions,the minimum value of the segmentation factor XS was 0.008.It was worth noting that at the low Reynolds number(Re<30),the change of curved shape on the capillary microreactor can significantly improve the micromixing performance with XS reduced by 37.5%.Further,the correlations of segment index XS with dimensionless factor such as Reynolds number or Dean number were developed,which can be used to predict the liquid-liquid micromixing performance in capillary microreactors.
基金fund major project“Research on China’s Natural Resources Capitalization and Corresponding Market Construction”(No.:15zdb163)Construction project of key disciplines of business administration in Jiangsu Province during the 14th five-year plan(SJYH2022-2/285).
文摘In China,the oversupply of coal occurred in 2009,and from that year onwards,China’s coal economy began a low-carbon and clean transformation.Evaluating transformation performance is the research goal of this paper.The data collection for this paper includes data on deep processing of Chinese coal products from 2009 to 2020,as well as data on asset structure evolution and financial performance of 34 listed companies in the Chinese coal mining.Entropy value method is used to calculate the entropy value of low-carbon transformation,and the regression analysis is used to study the performance of cleaner transformation,the conclusion is as follows:(1)From 2009 to 2020,in China’s total energy consumption,coal consumption accounted for 71.6%in 2009 and 56.8%in 2020,the goals set by the state have been achieved.(2)The national goal of reducing the proportion of coal consumption and reducing carbon emissions has forced the transformation of deep processing of coal products.The transformation of coal enterprises towards low-carbon and clean production has achieved remarkable results.(3)From 2009 to 2020,the non coal industry income of 34 listed companies in China’s coal mining industry increased by 8.21%annually.At the same time,the asset structure was adjusted,and nearly 80%of the asset structure evolution showed an orderly development trend.(4)The regression analysis results show that the entropy value of coal deep processing products and the entropy value of asset structure adjustment are significantly related to transformation performance.The paper proposes to summarize the successful experience of China’s coal energy economic transformation,lay a foundation for achieving the carbon peak and carbon neutral goals in the future,further increase the intensity of coal deep processing,increase the proportion of clean energy in total energy consumption,and strive to control asset operation towards the goal of increasing the proportion of non coal industry income.
基金supported by the Science Development Funding Program of Dongying of China(Grant No.DJ2021006)Science Development Funding Program of Dongying of China(Grant No.DJ2021008).
文摘The Mixed Refrigerant(MR)component is an important factor influencing the performances of natural gas lique-faction processes.However,there is a lack of systematic research about the utilization of propane pre-cooled(C3/MRC).In this paper,this mixed refrigerant cycle liquefaction process is simulated using the HYSYS software and the main influential parameters involved in the process are varied to analyze their influence on the liquefaction rate and power consumption.The results show that an effective way for lowering the power consumption of the compressor consists of reducing the flow through the compressor through optimization of the percentage of mixed refrigerant.The power consumption of the compressor in the hybrid refrigeration process is affected by both flow and pressure ratios.Its specific power consumption can be reduced by increasing the flow and decreasing the pressure ratio at the same time.The increase in refrigerant pressure at the high-pressure end can significantly mitigate the energy loss of the heat exchanger and compressor.
基金This project is supported by National Natural Science Foundation of China (No. 70471009)Natural Science Foundation Project of CQ CSTC, China (No. 2006BA2033).
文摘A set of indices for performance evaluation for business processes with multiple inputs and multiple outputs is proposed, which are found in machinery manufacturers. Based on the traditional methods of data envelopment analysis (DEA) and analytical hierarchical process (AHP), a hybrid model called DEA/AHP model is proposed to deal with the evaluation of business process performance. With the proposed method, the DEA is firstly used to develop a pairwise comparison matrix, and then the AHP is applied to evaluate the performance of business process using the pairwise comparison matrix. The significant advantage of this hybrid model is the use of objective data instead of subjective human judgment for performance evaluation. In the case study, a project of business process reengineering (BPR) with a hydraulic machinery manufacturer is used to demonstrate the effectiveness of the DEA/AHP model.
文摘Solidification processes of Al7SiMg-xY(0.1wt%,0.3wt%,0.5wt%) alloys were investigated by thermal analysis.The microstructures were observed by using optical microscopy and scanning electron microscopy.Effects of different concentrations of yttrium on tensile performance both as cast and T6 heat treated were studied at room temperature,respectively.The results show that little changes happen in liquidus with increases concentration of yttrium.While it results in obvious depression of solidus and eutectic arrest temperature in solidification process.Moreover,the solidification range increases significantly.The performance is better when concentration of yttrium is 0.1wt%.With increment of yttrium,more large flake-like compounds of yttrium gather in grain boundaries,performance especially the elongation of the alloy decrease remarkably.
基金the financial support by the Natural Science Foundation of Guangdong Province(2019A1515012111)the National Natural Science Foundation of China(51804199 and 51604081)+2 种基金the Science and Technology Innovation Commission of Shenzhen(JCYJ20190808173815205 and 20180123)the Shenzhen Science and Technology Program(KQTD20180412181422399)“Chenguang Program”supported by Shanghai Education Development Foundation and Shanghai Municipal Education Commission(16CG40)。
文摘To solve the critical problems of lithium rich cathode materials, e.g., structure instability and short cycle life, we have successfully prepared a ZrO2-coated and Zr-doping xLi2MnO3·(1–x)LiMO2 hollow architecture via one-time sintering process. The modified structural materials as lithium-ion cathodes present good structural stability and superior cycle performance in LIBs. The discharge capacity of the ZrO2-coated and Zr-doped hollow pristine is 220 mAh g-1 at the 20th cycle at 0.2 C(discharge capacity loss, 2.7%)and 150 m Ah g-1 at the 100 th cycle at 1 C(discharge capacity loss, 17.7%), respectively. However, hollow pristine electrode only delivers 203 m Ah g-1 at the 20 th cycle at 0.2 C and 124 mAh g-1 at the 100 th cycle at 1 C, respectively, and the corresponding to capacity retention is 92.2% and 72.8%, respectively.Diffusion coefficients of modified hollow pristine electrode are much higher than that of hollow pristine electrode after 100 cycles(approach to 1.4 times). In addition, we simulate the adsorption reaction of HF on the surface of ZrO2-coated layer by the first-principles theory. The calculations prove that the adsorption energy of HF on the surface of ZrO2-coated layer is about-1.699 e V, and the ZrO2-coated layer could protect the hollow spherical xLi2MnO3·(1–x)LiMO2 from erosion by HF. Our results would be applicable for systematic amelioration of high-performance lithium rich material for anode with the respect of practical application.
基金Supported by Technology Research and Development Project of Heilongjiang Province(GB14D202)
文摘This paper selected the corn processing industry technology innovation alliance in Heilongjiang Province as the research object, evaluated the operational performance of the alliance by using analytic hierarchy process(AHP) and fuzzy comprehensive evaluation methods. AHP empirical results showed that the satisfaction of information communication and the satisfaction of the management process were the weakest. And the order from high to low on the level of indicators of the impact for the alliance was the result of alliance operations and the process of alliance operations, the behavioral attitude of alliance members. Besides, the results of fuzzy comprehensive evaluation showed that the operational performance of the corn processing industry technology innovation alliance in Heilongjiang Province was in the general level.
基金supported by the National Key Research and Development Program of China(Grant No.Q2019YFE0107200)。
文摘The doping process and thermoelectric properties of donor-acceptor(D-A)type copolymers are investigated with the representative poly([2,6-4,8-di(5-ethylhexylthienyl)benzo[1,2-b;3,3-b]dithiophene]3-fluoro-2-[(2-ethylhexyl)-carbonyl]thieno[3,4-b]thiophenediyl))(PTB7-Th).The PTB7-Th is doped by Fe Cl;and only polarons are induced in its doped films.The results reveal that the electron-rich donor units within PTB7-Th lose electrons preferentially at the initial stage of the oxidation and then the acceptor units begin to be oxidized at a high doping concentration.The energy levels of polarons and the Fermi level of the doped PTB7-Th remain almost unchange with different doping levels.However,the morphology of the PTB7-Th films could be deteriorated as the doping levels are improved,which is one of the main reasons for the decrease of electrical conductivity at the later stage of doping.The best electrical conductivity and power factor are obtained to be 42.3 S·cm^(-1);and 33.9μW·mK^(-1),respectively,in the doped PTB7-Th film at room temperature.The power factor is further improved to 38.3μW·mK^(-1);at 75℃.This work may provide meaningful experience for development of D-A type thermoelectric copolymers and may further improve the doping efficiency.
文摘In recent years, the widespread adoption of parallel computing, especially in multi-core processors and high-performance computing environments, ushered in a new era of efficiency and speed. This trend was particularly noteworthy in the field of image processing, which witnessed significant advancements. This parallel computing project explored the field of parallel image processing, with a focus on the grayscale conversion of colorful images. Our approach involved integrating OpenMP into our framework for parallelization to execute a critical image processing task: grayscale conversion. By using OpenMP, we strategically enhanced the overall performance of the conversion process by distributing the workload across multiple threads. The primary objectives of our project revolved around optimizing computation time and improving overall efficiency, particularly in the task of grayscale conversion of colorful images. Utilizing OpenMP for concurrent processing across multiple cores significantly reduced execution times through the effective distribution of tasks among these cores. The speedup values for various image sizes highlighted the efficacy of parallel processing, especially for large images. However, a detailed examination revealed a potential decline in parallelization efficiency with an increasing number of cores. This underscored the importance of a carefully optimized parallelization strategy, considering factors like load balancing and minimizing communication overhead. Despite challenges, the overall scalability and efficiency achieved with parallel image processing underscored OpenMP’s effectiveness in accelerating image manipulation tasks.
基金Supported by Animal Genetic Resources and Utilization Innovation Platform of Foshan City(FCG[2014]136)Foshan Engineering Research Center for Animal Breeding(FK[2015]182)
文摘[Objective] The paper was to compare the effects of traditional granulating process and post-expanding lower temperature granulating process on starch gelatinization degree and in vitro protein digestibility of conversation feed, and growth performance of piglets. [Method] Sixty weaned piglets, 25 days old, were randomly divided into two groups, six replicates each group, and each replicate contained five piglets. Piglets in control group were fed with the conversation feed developed by traditional granulating process, and those in experimental group were fed with the conservation feed developed by post-expanding lower temperature granulating process. The trial lasted 28 d. [Result] Compared to traditional granulating process, post-expanding lower temperature granulating process significantly enhanced starch gelatinization degree of conservation feed by56.9%(P〈0.05), and significantly improved in vitro protein digestibility of conservation feed by 11.48%(P〈0.05). Compared to the control group, the feed intake of piglets in experimental group was increased by 21.63%(P〈0.05); the average daily gain was increased by 27.61%(P〈0.05); the diarrhea rate was lowered; and the feed gain ratio was improved by 4.51%(P〉0.05). The results suggested that post-expanding lower temperature granulating process effectively enhanced feed digestion and absorption of piglets. [Conclusion] The paper provides a theoretical basis and practical reference for improvement of production process of conservation feed.
文摘Evaluating performance of individual features of WiMAX technology is a topic of widespread discussion. Currently, there is no quantitative way of measuring WiMAX technology so that wireless operators can meet their design objectives. This paper outlines a set of design criteria for WiMAX and provides a decision-making aid that ranks the importance of criteria using Analytic Hierarchy Process (AHP). This ranking should sufficiently reflect market expectations of the relative importance of various design criteria. A model integrating AHP priorities with enhanced Data Envelopment Analysis (DEA) is the basis for formulating a technological value in simple, comparable format. A case study is provided to show how this technological value is used to evaluate a three year network deployment plan. In the future, this model could be extended to WiMAX equipment suppliers for the purpose of validating performance targets of individual criteria, and enhancing supplier roadmaps for future network development.
文摘It is acknowledged that lacking of interdisciplinary communication amongst designers can result in poor coordination performance in building design. Viewing communication as information processing activity, this paper aims to explore the relationship between interdisciplinary information processing (IP) and design coordination performance. Both amount and quality are concerned regarding information processing. 698 project based samples are collected by questionnaire survey from design institutes in China's Mainland. Statistical data analysis shows that the relationship between information processing amount and design coordination performance follows a nonlinear exponential expression: performance = 3.691 (1-0.235IP amount) rather than reverted U curve. It implies that design period is too short to allow information overload. It indicates that the main problem in interdisciplinary communication in design institute in China is insufficient information. In additional, it is found the correlation between IP quality and coordination process performance is much stronger than that between IP amount and coordination process performance. For practitioners, it reminds design mangers to pay more attention to information processing quality rather than amount.
文摘Based on the analysis of the common limitations of business processmanagement (BPM) methodologies and the requirements of small and medium sized-enterprises (SMEs),the importance of a 'performance construct' of BPM methodologies is identified, a six-phaseperformance-driven BPM methodology for the production and operation processes of Chinese SMEs isdeveloped. A case study on the process management of a medium-sized enterprise shows a successfulexample of running the methodology.
文摘Some statistical characteristics of signal and noise in shallow-water acoustical channel were analysed . Based on the differences in some statistical characteristics between the signal and the noise , the authors developed a new kind of signal processing technique-digital time correlative accumulation to operate sonar systems at a low data rate . Theoretical analyses and expermental results show . the false-alarm probability can be reduced to a low value of less than 10 -4 while the detection probability can reach a relatively high value of more than 0.9. By using the statistical averages of the multiple range detection value , the authors can greatly improve the accuracy of the detection . The method can be used for some other related fields, for example , ultrasonic detection in air medium .
基金supported by the National Key Research and Development Program of China under Grant No.2023YFB4502300.
文摘Graph processing has been widely used in many scenarios,from scientific computing to artificial intelligence.Graph processing exhibits irregular computational parallelism and random memory accesses,unlike traditional workloads.Therefore,running graph processing workloads on conventional architectures(e.g.,CPUs and GPUs)often shows a significantly low compute-memory ratio with few performance benefits,which can be,in many cases,even slower than a specialized single-thread graph algorithm.While domain-specific hardware designs are essential for graph processing,it is still challenging to transform the hardware capability to performance boost without coupled software codesigns.This article presents a graph processing ecosystem from hardware to software.We start by introducing a series of hardware accelerators as the foundation of this ecosystem.Subsequently,the codesigned parallel graph systems and their distributed techniques are presented to support graph applications.Finally,we introduce our efforts on novel graph applications and hardware architectures.Extensive results show that various graph applications can be efficiently accelerated in this graph processing ecosystem.
基金supported by the National Natural Science Foundation of China (No.51701061)the Natural Science Foundation of Hebei Province (Nos.E2023202047 and E2021202075)+1 种基金the Key-Area R&D Program of Guangdong Province (No.2020B0101340004)Guangdong Academy of Science (2021GDASYL-20210102002).
文摘Steels are widely used as structural materials,making them essential for supporting our lives and industries.However,further improving the comprehensive properties of steel through traditional trial-and-error methods becomes challenging due to the continuous development and numerous processing parameters involved in steel production.To address this challenge,the application of machine learning methods becomes crucial in establishing complex relationships between manufacturing processes and steel performance.This review begins with a general overview of machine learning methods and subsequently introduces various performance predictions in steel materials.The classification of performance pre-diction was used to assess the current application of machine learning model-assisted design.Several important issues,such as data source and characteristics,intermediate features,algorithm optimization,key feature analysis,and the role of environmental factors,were summarized and analyzed.These insights will be beneficial and enlightening to future research endeavors in this field.
基金The research of Falei Wang is supported by the National Natural Science Foundation of China(Grant Nos.12171280 and 12031009)the Natural Science Foundation of Shandong Province(Grant Nos.ZR2021YQ01 and ZR2022JQ01)the National Key Research&Development Program of China(Grant No.2018YFA0703900).
文摘We introduce a new type of robust forward criterion under model uncertainty,called the G-forward performance process,which extends the classical notion of forward performance process to the G-expectation framework.We then derive the representations of homothetic G-forward performance processes in a single stochastic factor model with uncertainty,building on the well-posedness of ergodic and infinite horizon backward stochastic differential equations driven by G-Brownian motion(G-BSDEs)with quadratic generators.
文摘An alpha-uniformized Markov chain is defined by the concept of equivalent infinitesimalgenerator for a semi-Markov decision process (SMDP) with both average- and discounted-criteria.According to the relations of their performance measures and performance potentials, the optimiza-tion of an SMDP can be realized by simulating the chain. For the critic model of neuro-dynamicprogramming (NDP), a neuro-policy iteration (NPI) algorithm is presented, and the performanceerror bound is shown as there are approximate error and improvement error in each iteration step.The obtained results may be extended to Markov systems, and have much applicability. Finally, anumerical example is provided.