The power Internet of Things(IoT)is a significant trend in technology and a requirement for national strategic development.With the deepening digital transformation of the power grid,China’s power system has initiall...The power Internet of Things(IoT)is a significant trend in technology and a requirement for national strategic development.With the deepening digital transformation of the power grid,China’s power system has initially built a power IoT architecture comprising a perception,network,and platform application layer.However,owing to the structural complexity of the power system,the construction of the power IoT continues to face problems such as complex access management of massive heterogeneous equipment,diverse IoT protocol access methods,high concurrency of network communications,and weak data security protection.To address these issues,this study optimizes the existing architecture of the power IoT and designs an integrated management framework for the access of multi-source heterogeneous data in the power IoT,comprising cloud,pipe,edge,and terminal parts.It further reviews and analyzes the key technologies involved in the power IoT,such as the unified management of the physical model,high concurrent access,multi-protocol access,multi-source heterogeneous data storage management,and data security control,to provide a more flexible,efficient,secure,and easy-to-use solution for multi-source heterogeneous data access in the power IoT.展开更多
The catalytic conversion of CO_(2) to fuels or chemicals is considered to be an effective pathway to mitigate the greenhouse effect. To develop new types of efficient and durable catalysts, it is critical to identify ...The catalytic conversion of CO_(2) to fuels or chemicals is considered to be an effective pathway to mitigate the greenhouse effect. To develop new types of efficient and durable catalysts, it is critical to identify the catalytic active sites, surface intermediates, and reaction mechanisms to reveal the relationship between the active sites and catalytic performance. However, the structure of a heterogeneous catalyst usually dynamically changes during reaction, bringing a great challenge for the identification of catalytic active sites and reaction pathways. Therefore, in-situ/operando techniques have been employed to real-time monitor the dynamic evolution of the structure of active sites under actual reaction conditions to precisely build the structure–function relationship. Here, we review the recent progress in the application of various in-situ/operando techniques in identifying active sites for catalytic conversion of CO_(2) over heterogeneous catalysts. We systematically summarize the applications of various optical and X-ray spectroscopy techniques, including Raman spectroscopy, Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and X-ray absorption spectroscopy (XAS), in identifying active sites and determining reaction mechanisms of the CO_(2) thermochemical conversion with hydrogen and light alkanes over heterogeneous catalysts. Finally, we discuss challenges and opportunities for the development of in-situ characterization in the future to further enlarge the capability of these powerful techniques.展开更多
Integration of the high-quality Ga Sb layer on an Si substrate is significant to improve the Ga Sb application in optoelectronic integration.In this work,a suitable ion implantation fluence of 5×10^(16)-cm^(-2)H ...Integration of the high-quality Ga Sb layer on an Si substrate is significant to improve the Ga Sb application in optoelectronic integration.In this work,a suitable ion implantation fluence of 5×10^(16)-cm^(-2)H ions for Ga Sb layer transfer is confirmed.Combining the strain change and the defect evolution,the blistering and exfoliation processes of Ga Sb during annealing is revealed in detail.With the direct wafer bonding,the Ga Sb layer is successfully transferred onto a(100)Si substrate covered by 500-nm thickness thermal oxide SiO_(2)layer.After being annealed at 200℃,the Ga Sb layer shows high crystalline quality with only 77 arcsec for the full width at half maximum(FWHM)of the x-ray rocking curve(XRC).展开更多
Sensor nodes are mainly shielded in the field with limited power supply. In Wireless Sensor Networks, there must be a requirement of an efficient power management, because sensor nodes are deployed in unman attended a...Sensor nodes are mainly shielded in the field with limited power supply. In Wireless Sensor Networks, there must be a requirement of an efficient power management, because sensor nodes are deployed in unman attended area with non-rechargeable batteries. Power management can be done by different methods of routing protocols. The proposed Reliable Rim Routing (3R) technique is based on hybrid routing protocol for homogeneous and heterogeneous system for WSNs to ameliorate the performance of the overall system. In 3R, total node deployment area can be multipart in terms of rim and in each rim, and some of the sensor nodes transmit their sensed data directly to base station, and meanwhile remaining sensor nodes send the data through clustering technique to base station like SEP. Proposed 3R technique implementation proves its enhanced WSNs lifetime of 70% energy consumption and 40% throughput compared with existing protocols. Simulation and evaluation results outperformed in terms of energy consumption with increased throughput and network lifetime.展开更多
In this study,high-gravity intensified heterogeneous catalytic ozonation is utilized for treatment of phenol-containing wastewater,and the kinetics of the direct reaction between ozone and phenol in the presence of ex...In this study,high-gravity intensified heterogeneous catalytic ozonation is utilized for treatment of phenol-containing wastewater,and the kinetics of the direct reaction between ozone and phenol in the presence of excess tertiary butanol(TBA)is investigated.It is revealed that the direct reaction between ozone and phenol in the rotating packed bed(RPB)follows the pseudo-first-order kinetics with a reaction rate constant higher than that in the conventional bubbling reactor(BR).Under different conditions of temperature,initial pH,high-gravity factor,and gaseous ozone concentration,the apparent reaction rate constant varies in the range of 0.0160–0.115 min-1.An empirical power-exponential model is established to characterize the effects of these parameters on the direct reaction between ozone and phenol by high-gravity intensified heterogeneous catalytic ozonation.展开更多
Due to advances in semiconductor techniques, many-core processors have been widely used in high performance computing. However, many applications still cannot be carried out efficiently due to the memory wall, which h...Due to advances in semiconductor techniques, many-core processors have been widely used in high performance computing. However, many applications still cannot be carried out efficiently due to the memory wall, which has become a bottleneck in many-core processors. In this paper, we present a novel heterogeneous many-core processor architecture named deeply fused many-core (DFMC) for high performance computing systems. DFMC integrates management processing ele- ments (MPEs) and computing processing elements (CPEs), which are heterogeneous processor cores for different application features with a unified ISA (instruction set architecture), a unified execution model, and share-memory that supports cache coherence. The DFMC processor can alleviate the memory wall problem by combining a series of cooperative computing techniques of CPEs, such as multi-pattern data stream transfer, efficient register-level communication mechanism, and fast hardware synchronization technique. These techniques are able to improve on-chip data reuse and optimize memory access performance. This paper illustrates an implementation of a full system prototype based on FPGA with four MPEs and 256 CPEs. Our experimental results show that the effect of the cooperative computing techniques of CPEs is significant, with DGEMM (double-precision matrix multiplication) achieving an efficiency of 94%, FFT (fast Fourier transform) obtaining a performance of 207 GFLOPS and FDTD (finite-difference time-domain) obtaining a performance of 27 GFLOPS.展开更多
Nowadays,the management of resource contention in shared cloud remains a pending problem.The evolution and deployment of new application paradigms(e.g.,deep learning training and microservices)and custom hardware(e.g....Nowadays,the management of resource contention in shared cloud remains a pending problem.The evolution and deployment of new application paradigms(e.g.,deep learning training and microservices)and custom hardware(e.g.,graphics processing unit(GPU)and tensor processing unit(TPU))have posed new challenges in resource management system design.Current solutions tend to trade cluster efficiency for guaranteed application performance,e.g.,resource over-allocation,leaving a lot of resources underutilized.Overcoming this dilemma is not easy,because different components across the software stack are involved.Nevertheless,massive efforts have been devoted to seeking effective performance isolation and highly efficient resource scheduling.The goal of this paper is to systematically cover related aspects to deliver the techniques from the coordination perspective,and to identify the corresponding trends they indicate.Briefly,four topics are involved.First,isolation mechanisms deployed at different levels(micro-architecture,system,and virtualization levels)are reviewed,including GPU multitasking methods.Second,resource scheduling techniques within an individual machine and at the cluster level are investigated,respectively.Particularly,GPU scheduling for deep learning applications is described in detail.Third,adaptive resource management including the latest microservice-related research is thoroughly explored.Finally,future research directions are discussed in the light of advanced work.We hope that this review paper will help researchers establish a global view of the landscape of resource management techniques in shared cloud,and see technology trends more clearly.展开更多
基金supported by the National Key Research and Development Program of China(grant number 2019YFE0123600)。
文摘The power Internet of Things(IoT)is a significant trend in technology and a requirement for national strategic development.With the deepening digital transformation of the power grid,China’s power system has initially built a power IoT architecture comprising a perception,network,and platform application layer.However,owing to the structural complexity of the power system,the construction of the power IoT continues to face problems such as complex access management of massive heterogeneous equipment,diverse IoT protocol access methods,high concurrency of network communications,and weak data security protection.To address these issues,this study optimizes the existing architecture of the power IoT and designs an integrated management framework for the access of multi-source heterogeneous data in the power IoT,comprising cloud,pipe,edge,and terminal parts.It further reviews and analyzes the key technologies involved in the power IoT,such as the unified management of the physical model,high concurrent access,multi-protocol access,multi-source heterogeneous data storage management,and data security control,to provide a more flexible,efficient,secure,and easy-to-use solution for multi-source heterogeneous data access in the power IoT.
基金supported by Yunnan Fundamental Research Projects(No.202201BE070001-014)Doctoral Scientific Research Foundation of Hubei University of Automotive Technology(No.BK202336)+4 种基金National Natural Science Foundation of China(No.52071035)Program for Science and Technology Innovation Team in Colleges of Hubei Province(No.T2021012)Outstanding Young Scientific&Technological Innovation Team Plan of Colleges and Universities in Hubei Province(No.T201518 and No.T201811)Major Science and Technology Project of Hubei Province(No.2022AAA001)Key R&D Project of Hubei Province(No.2021BAB019)。
基金Authors acknowledge the financial support from the National Natural Science Foundation of China(NSFC)under Grant No.21978148 and 21808120.
文摘The catalytic conversion of CO_(2) to fuels or chemicals is considered to be an effective pathway to mitigate the greenhouse effect. To develop new types of efficient and durable catalysts, it is critical to identify the catalytic active sites, surface intermediates, and reaction mechanisms to reveal the relationship between the active sites and catalytic performance. However, the structure of a heterogeneous catalyst usually dynamically changes during reaction, bringing a great challenge for the identification of catalytic active sites and reaction pathways. Therefore, in-situ/operando techniques have been employed to real-time monitor the dynamic evolution of the structure of active sites under actual reaction conditions to precisely build the structure–function relationship. Here, we review the recent progress in the application of various in-situ/operando techniques in identifying active sites for catalytic conversion of CO_(2) over heterogeneous catalysts. We systematically summarize the applications of various optical and X-ray spectroscopy techniques, including Raman spectroscopy, Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and X-ray absorption spectroscopy (XAS), in identifying active sites and determining reaction mechanisms of the CO_(2) thermochemical conversion with hydrogen and light alkanes over heterogeneous catalysts. Finally, we discuss challenges and opportunities for the development of in-situ characterization in the future to further enlarge the capability of these powerful techniques.
基金the National Key Research and Development Program of China(Grant No.2017YFE0131300)the National Natural Science Foundation of China(Grant Nos.U1732268,61874128,11622545,61851406,11705262,61875220,and 61804157)+6 种基金the Frontier Science Key Program of Chinese Academy of Sciences(Grant Nos.QYZDYSSW-JSC032 and ZDBS-LY-JSC009)the Chinese–Austrian Cooperative Research and Development Project(Grant No.GJHZ201950)the Shanghai Science and Technology Innovation Action Plan Program,China(Grant No.17511106202)the Program of Shanghai Academic Research Leader,China(Grant No.19XD1404600)the Shanghai Youth Top Talent Program,Shanghai Sailing Program,China(Grant Nos.19YF1456200 and 19YF1456400)the K.C.Wong Education Foundation,China(Grant No.GJTD2019-11)the NCBiR within the Polish–China(Grant No.WPC/130/NIR-Si/2018)。
文摘Integration of the high-quality Ga Sb layer on an Si substrate is significant to improve the Ga Sb application in optoelectronic integration.In this work,a suitable ion implantation fluence of 5×10^(16)-cm^(-2)H ions for Ga Sb layer transfer is confirmed.Combining the strain change and the defect evolution,the blistering and exfoliation processes of Ga Sb during annealing is revealed in detail.With the direct wafer bonding,the Ga Sb layer is successfully transferred onto a(100)Si substrate covered by 500-nm thickness thermal oxide SiO_(2)layer.After being annealed at 200℃,the Ga Sb layer shows high crystalline quality with only 77 arcsec for the full width at half maximum(FWHM)of the x-ray rocking curve(XRC).
文摘Sensor nodes are mainly shielded in the field with limited power supply. In Wireless Sensor Networks, there must be a requirement of an efficient power management, because sensor nodes are deployed in unman attended area with non-rechargeable batteries. Power management can be done by different methods of routing protocols. The proposed Reliable Rim Routing (3R) technique is based on hybrid routing protocol for homogeneous and heterogeneous system for WSNs to ameliorate the performance of the overall system. In 3R, total node deployment area can be multipart in terms of rim and in each rim, and some of the sensor nodes transmit their sensed data directly to base station, and meanwhile remaining sensor nodes send the data through clustering technique to base station like SEP. Proposed 3R technique implementation proves its enhanced WSNs lifetime of 70% energy consumption and 40% throughput compared with existing protocols. Simulation and evaluation results outperformed in terms of energy consumption with increased throughput and network lifetime.
基金supported by the Fund for Shanxi Province Higher Education“1331 Project”for Improving Quality and Efficiency Construction(nuc2021-006)Key Research&Development Plan of Shanxi Province(201903D321059)+1 种基金Scientific Activities of Selected Returned Overseas Professionals in Shanxi Province(20200004)Transformation and Cultivation Projects of Scientific and Technological Achievements in Universities of Shanxi Province Institutions(2020CG040).
文摘In this study,high-gravity intensified heterogeneous catalytic ozonation is utilized for treatment of phenol-containing wastewater,and the kinetics of the direct reaction between ozone and phenol in the presence of excess tertiary butanol(TBA)is investigated.It is revealed that the direct reaction between ozone and phenol in the rotating packed bed(RPB)follows the pseudo-first-order kinetics with a reaction rate constant higher than that in the conventional bubbling reactor(BR).Under different conditions of temperature,initial pH,high-gravity factor,and gaseous ozone concentration,the apparent reaction rate constant varies in the range of 0.0160–0.115 min-1.An empirical power-exponential model is established to characterize the effects of these parameters on the direct reaction between ozone and phenol by high-gravity intensified heterogeneous catalytic ozonation.
基金Supported by the National Natural Science Foundation of China (No. 60872018), the Natural Science Foundation of Education Committee of Jiangsu Province ( No. 11KJB510014) and Scientific Research Foundation of NUPT ( No. NY210004).
文摘Due to advances in semiconductor techniques, many-core processors have been widely used in high performance computing. However, many applications still cannot be carried out efficiently due to the memory wall, which has become a bottleneck in many-core processors. In this paper, we present a novel heterogeneous many-core processor architecture named deeply fused many-core (DFMC) for high performance computing systems. DFMC integrates management processing ele- ments (MPEs) and computing processing elements (CPEs), which are heterogeneous processor cores for different application features with a unified ISA (instruction set architecture), a unified execution model, and share-memory that supports cache coherence. The DFMC processor can alleviate the memory wall problem by combining a series of cooperative computing techniques of CPEs, such as multi-pattern data stream transfer, efficient register-level communication mechanism, and fast hardware synchronization technique. These techniques are able to improve on-chip data reuse and optimize memory access performance. This paper illustrates an implementation of a full system prototype based on FPGA with four MPEs and 256 CPEs. Our experimental results show that the effect of the cooperative computing techniques of CPEs is significant, with DGEMM (double-precision matrix multiplication) achieving an efficiency of 94%, FFT (fast Fourier transform) obtaining a performance of 207 GFLOPS and FDTD (finite-difference time-domain) obtaining a performance of 27 GFLOPS.
基金Project supported by the National Key R&D Program,China(No.2016YFB1000204)。
文摘Nowadays,the management of resource contention in shared cloud remains a pending problem.The evolution and deployment of new application paradigms(e.g.,deep learning training and microservices)and custom hardware(e.g.,graphics processing unit(GPU)and tensor processing unit(TPU))have posed new challenges in resource management system design.Current solutions tend to trade cluster efficiency for guaranteed application performance,e.g.,resource over-allocation,leaving a lot of resources underutilized.Overcoming this dilemma is not easy,because different components across the software stack are involved.Nevertheless,massive efforts have been devoted to seeking effective performance isolation and highly efficient resource scheduling.The goal of this paper is to systematically cover related aspects to deliver the techniques from the coordination perspective,and to identify the corresponding trends they indicate.Briefly,four topics are involved.First,isolation mechanisms deployed at different levels(micro-architecture,system,and virtualization levels)are reviewed,including GPU multitasking methods.Second,resource scheduling techniques within an individual machine and at the cluster level are investigated,respectively.Particularly,GPU scheduling for deep learning applications is described in detail.Third,adaptive resource management including the latest microservice-related research is thoroughly explored.Finally,future research directions are discussed in the light of advanced work.We hope that this review paper will help researchers establish a global view of the landscape of resource management techniques in shared cloud,and see technology trends more clearly.