This paper describes a method of calculating the Schur complement of a sparse positive definite matrix A. The main idea of this approach is to represent matrix A in the form of an elimination tree using a reordering a...This paper describes a method of calculating the Schur complement of a sparse positive definite matrix A. The main idea of this approach is to represent matrix A in the form of an elimination tree using a reordering algorithm like METIS and putting columns/rows for which the Schur complement is needed into the top node of the elimination tree. Any problem with a degenerate part of the initial matrix can be resolved with the help of iterative refinement. The proposed approach is close to the “multifrontal” one which was implemented by Ian Duff and others in 1980s. Schur complement computations described in this paper are available in Intel®Math Kernel Library (Intel®MKL). In this paper we present the algorithm for Schur complement computations, experiments that demonstrate a negligible increase in the number of elements in the factored matrix, and comparison with existing alternatives.展开更多
The paper describes an efficient direct method to solve an equation Ax = b, where A is a sparse matrix, on the Intel®Xeon PhiTM coprocessor. The main challenge for such a system is how to engage all available ...The paper describes an efficient direct method to solve an equation Ax = b, where A is a sparse matrix, on the Intel®Xeon PhiTM coprocessor. The main challenge for such a system is how to engage all available threads (about 240) and how to reduce OpenMP* synchronization overhead, which is very expensive for hundreds of threads. The method consists of decomposing A into a product of lower-triangular, diagonal, and upper triangular matrices followed by solves of the resulting three subsystems. The main idea is based on the hybrid parallel algorithm used in the Intel®Math Kernel Library Parallel Direct Sparse Solver for Clusters [1]. Our implementation exploits a static scheduling algorithm during the factorization step to reduce OpenMP synchronization overhead. To effectively engage all available threads, a three-level approach of parallelization is used. Furthermore, we demonstrate that our implementation can perform up to 100 times better on factorization step and up to 65 times better in terms of overall performance on the 240 threads of the Intel®Xeon PhiTM coprocessor.展开更多
With the increasing importance of cloud services worldwide, the cloud infrastructure and platform management has become critical for cloud service providers. In this paper, a novel architecture of intelligent server m...With the increasing importance of cloud services worldwide, the cloud infrastructure and platform management has become critical for cloud service providers. In this paper, a novel architecture of intelligent server management framework is proposed. In this framework, the communication layer is based on the Extensible Messaging and Presence Protocol (XMPP), which was developed for instant messaging and has been proven to be highly mature and suitable for mobile and large scalable deployment due to its extensibility and efficiency. The proposed architecture can simplify server management and increase flexibility and scalability when managing hundreds of thousands of servers in the cloud era.展开更多
Intelligent manufacturing(IM),a driving force behind the fourth industrial revolution,is reshaping the manufacturing sector by enhancing productivity,efficiency,and sustainability.Despite the rapid technological advan...Intelligent manufacturing(IM),a driving force behind the fourth industrial revolution,is reshaping the manufacturing sector by enhancing productivity,efficiency,and sustainability.Despite the rapid technological advancements in IM,comprehensive bibliometric reviews remain limited.This article systematically reviews the latest research in IM,addressing emerging hotspots,key technologies,and their applications across the entire product manufacturing cycle.Bibliometric analysis is employed to identify research trends visualize publication volume,collaboration patterns,research domains,co-citations,and emerging areas of interest.The article then examines key technologies supporting IM,including sensors,the Internet of Things(IoT),big data analytics,cloud computing,artificial intelligence(AI),digital twins,and virtual reality(VR)/augmented reality(AR).Furthermore,it explores the application of these technologies throughout the manufacturing cycle-from intelligent reliability design,material transportation and tracking,to intelligent planning and scheduling,machining and fabrication,monitoring and maintenance,quality inspection and control,warehousing and management,and sustainable green manufacturing—through specific case studies.Lastly,the article discusses future research directions,highlighting the increasing global market and the need for enhanced interdisciplinary collaboration,technological integration,computing power upgrades,and attention to security and privacy in IM.This study provides valuable insights for scholars and serves as a guide for future research and strategic investment decisions,offering a comprehensive view of the IM field.展开更多
Mg-Gd based alloys are an important class of high-performance Mg alloys.In this study,three Mg-Gd alloys with different gadolinium(Gd)contents:Mg-9.54Gd-0.40Zr(wt.%,G10 K),Mg-15.11Gd-0.35Zr(wt.%,G15 K)and Mg-19.67Gd-0...Mg-Gd based alloys are an important class of high-performance Mg alloys.In this study,three Mg-Gd alloys with different gadolinium(Gd)contents:Mg-9.54Gd-0.40Zr(wt.%,G10 K),Mg-15.11Gd-0.35Zr(wt.%,G15 K)and Mg-19.67Gd-0.33Zr(wt.%,G20 K)were prepared by semicontinuous casting and subsequent solution and aging heat treatments.The role of Gd content on microstructures and mechanical properties of the Mg-Gd-Zr alloy is studied.All three as-cast alloys exhibit eutectic phases of Mg_(5)Gd,with the amount increasing as the Gd content rises.Mg_(5)Gd disappears after the solution heat treatment(the G10 K alloy solution-treated at 480℃ for 4 h,the G15 K alloy at 500℃ for 12 h and the G20 K alloy at 520℃ for 24 h,respectively).Aging heat treatment at 200℃ for 64 h after solution introduces numerous prismatic β' precipitates,with a significant increase in their area number density corresponding to increased Gd content.Additionally,the morphology of the β' precipitates exhibits distinct variations:the G10 K alloy is characterized by an enhanced aspect ratio.Consequently,the peak-aged G10 K alloy demonstrates superior strength-ductility synergy,with a yield strength(YS)of 216±1 MPa,an ultimate tensile strength(UTS)of 363±1 MPa,and an elongation(EL)of 8.7±0.6%.This study suggests that plasticity diminishes and precipitation strengthening is limited when the gadolinium content exceeds 15 wt.%.展开更多
Mobile Edge Computing(MEC) is an emerging technology in 5G era which enables the provision of the cloud and IT services within the close proximity of mobile subscribers.It allows the availability of the cloud servers ...Mobile Edge Computing(MEC) is an emerging technology in 5G era which enables the provision of the cloud and IT services within the close proximity of mobile subscribers.It allows the availability of the cloud servers inside or adjacent to the base station.The endto-end latency perceived by the mobile user is therefore reduced with the MEC platform.The context-aware services are able to be served by the application developers by leveraging the real time radio access network information from MEC.The MEC additionally enables the compute intensive applications execution in the resource constraint devices with the collaborative computing involving the cloud servers.This paper presents the architectural description of the MEC platform as well as the key functionalities enabling the above features.The relevant state-of-the-art research efforts are then surveyed.The paper finally discusses and identifies the open research challenges of MEC.展开更多
The effects of Bi addition on the growth of intermetallic compound (IMC) formation in Sn-3.8Ag-0.7Cu solder joints were investigated. The test samples were prepared by conventional surface mounting technology. To inve...The effects of Bi addition on the growth of intermetallic compound (IMC) formation in Sn-3.8Ag-0.7Cu solder joints were investigated. The test samples were prepared by conventional surface mounting technology. To investigate the element diffusion and the growth kinetics of intermetallics formation in solder joint, isothermal aging test was performed at temperatures of 100, 150, and 190℃, respectively. The optical microscope (OM) and scanning electron microscope (SEM) were used to observe microstructure evolution of solder joint and to estimate the thickness and the grain size of the intermetallic layers. The IMC phases were identified by energy dispersive X-ray (EDX) and X-ray diffractometer (XRD). The results clearly show that adding about 1.0% Bi in Sn-Ag-Cu solder alloy system can refine the grain size of the IMC and inhibit the excessive IMC growth in solder joints, and therefore improve the reliability of the Pb-free solder joints. Through observation of the microstructural evolution of the solder joints, the mechanism of inhibition of IMC growth due to Bi addition was proposed.展开更多
We synthesized NiO-loaded TiO2porous p-n junctions by electrophoretic enhanced micro arc oxidation（EEMAO） technique which is a relatively simple and new method for producing composite coatings.Phase structure,chemic...We synthesized NiO-loaded TiO2porous p-n junctions by electrophoretic enhanced micro arc oxidation（EEMAO） technique which is a relatively simple and new method for producing composite coatings.Phase structure,chemical composition,and surface morphology of the NiO—TiO2coatings were investigated by X-ray diffraction（XRD）,X-ray photoelectron spectroscopy（XPS）,and scanning electron microscopy（SEM） techniques,respectively.Photocatalytic efficiency of the samples was studied through measuring the decomposition rate of 4-chlorophenol under UV irradiation.Results showed that the coatings mainly consisted of anatase,rutile,and nickel oxide phases.It was observed that a finer surface morphology,i.e.smaller pores,was obtained at lower voltages.Besides,the amount of nickel oxide loaded to the TiO2host increased with the voltage.The NiO-TiO2composite coatings showed a higher photoactivity than pure TiO2coatings revealing the effective role of NiO in decreasing the recombination rate of photogenerated electrons and holes.The maximum photocatalytic reaction rate constants for TiO2and NiO—TiO2samples were obtained as 0.0064 and 0.0131 min-1,respectively.We also found that there was an optimum concentration of NiO where a maximum photocatalytic activity was achieved.A correlation between growth variables,structure,and photocatalytic efficiency was established.展开更多
Artificial intelligence(AI)algorithms achieve outstanding results in many applicationdomains such as computer vision and natural language processing The performance ofAl models is the outcome of complex and costly mod...Artificial intelligence(AI)algorithms achieve outstanding results in many applicationdomains such as computer vision and natural language processing The performance ofAl models is the outcome of complex and costly model architecture design and trainingprocesses.Hence,it is paramount for model owners to protect their AI models frompiracy-model cloning,illegitimate distribution and use.IP protection mechanisms havebeen applied to Al models,and in particular to deep neural networks,to verify themodel ownership.State-of-the-art AI model ownership protection techniques have beensurveyed.The pros and cons of Al model ownership protection have been reported.The majonity of previous works are focused on watermarking,while more advancedmethods such fingerprinting and attestation are promising but not yet explored indepth.This study has been concluded by discussing possible research directions in thearea.展开更多
To handle the effects of single event upsets（SEU）,which are common to computers in space radiation environment,a new fault-tolerant system with dual-module redundancy is proposed using dynamic reconfigurable techniq...To handle the effects of single event upsets（SEU）,which are common to computers in space radiation environment,a new fault-tolerant system with dual-module redundancy is proposed using dynamic reconfigurable technique of field programmable gate array（FPGA）. This system contains detection and backup alternative functions,that is,the self-detection and self-healing functions can be completed,and consequently a system design with low hardware redundancy and high resource utilization can be achieved successfully. So it can not only detect fault but also repair the fault effectively after failure. Hence,this method is especially practical to the dynamically reconfigurable computers based on FPGAs. Design methodology has been verified by Virtex-4 FPGA on Xilinx Ml403 development platform.展开更多
With the ever-increasing range of video and audio applications in portable handheld devices, demand for high throughput in Wi-Fi networks is escalating. In this paper we introduce several novel features defined in nex...With the ever-increasing range of video and audio applications in portable handheld devices, demand for high throughput in Wi-Fi networks is escalating. In this paper we introduce several novel features defined in next generation WLAN, termed as IEEE 802.11ax standard, and compare between the maximum throughputs received in IEEE 802.11ax and IEEE 802.11ac in a scenario where the AP continuously transmits to one station in the Single User mode. The comparison is done as a function of the modulation/coding schemes in use. In IEEE 802.11ax we consider two levels of frame aggregation. IEEE 802.11ax outperforms IEEE 802.11ac by about 29% and 48% in reliable and unreliable channels respectively.展开更多
Coupled inductor is one appealing technology to improve transient response and reduce output decoupling significantly in interleaved multi-phase voltage regulators (VRs). One well known problem is that coupled inducto...Coupled inductor is one appealing technology to improve transient response and reduce output decoupling significantly in interleaved multi-phase voltage regulators (VRs). One well known problem is that coupled inductor winding structure causes PCB routing path longer than discrete inductor design. This paper investigates possible PCB routing schemes for coupled inductor and conducts a fair and quantitative comparison with discrete inductor in a server VR design. Simulation and measurement are also conducted to verify the analysis.展开更多
A miniaturized square resonator bandpass filter with circular stubs is designed, fabricated, and characterized. Analytical calculations were carried out to determine the critical filter parameters and the design was o...A miniaturized square resonator bandpass filter with circular stubs is designed, fabricated, and characterized. Analytical calculations were carried out to determine the critical filter parameters and the design was optimized using a 3D electromagnetic finite-element solver. The measured results were in good agreement with the designed results. The proposed filter exhibits significant improvement in bandwidth compared to the conventional square resonator bandpass filters.展开更多
The processor is greatly hampered by the large dataset of picture or multimedia data.The logic of approximation hardware is moving in the direction of multimedia processing with a given amount of acceptable mistake.Th...The processor is greatly hampered by the large dataset of picture or multimedia data.The logic of approximation hardware is moving in the direction of multimedia processing with a given amount of acceptable mistake.This study proposes various higher-order approximate counter-based compressor(CBC)using input shuffled 6:3 CBC.In the Wallace multiplier using a CBC is a significant factor in partial product reduction.So the design of 10-4,11-4,12-4,13-4 and 14-4 CBC are proposed in this paper using an input shuffled 6:3 compressor to attain two stage multiplications.The input shuffling aims to reduce the output combination of the 6:3 compressor from 64 to 27.Design of 15-4,10-4,9-4,and 7-3 CBCs are performed using the proposed 6:3 compressor and the results obtained are compared with the existing models.These existing models are constructed using multiplexers and 5-3 CBC.When compared to input shuffled 5-3 the proposed 6:3 compressor shows better results in terms of area,power and delay.An approximation is performed on the 6:3 compressor to further reduce the computational energy of the system which is optimal for multimedia applications.The major contribution of this work is the development of two stage multiplier using various proposed CBC.All designs of the approximate compressor(AC)and true compressor(TC)are analysed with 8 ×8 and 16 × 16 imagemultiplication.The proposed multipliers also provide adequate levels of accuracy,according to the MATLAB simulations,in addition to greater hardware efficiency.As the result approximate circuits over image processing shows the stunning performance in many deep learning network in the current research which is only oriented to multimedia.展开更多
In this paper, we propose a novel uplink power control algorithm, SMST, for multiple-input multiple-output orthogonal frequency-division multiple access （MIMQ-OFDMA）.We perform an extensive system-level simulation t...In this paper, we propose a novel uplink power control algorithm, SMST, for multiple-input multiple-output orthogonal frequency-division multiple access （MIMQ-OFDMA）.We perform an extensive system-level simulation to compare different uplink power control algorithms, including the FPC adopted in 3GPP LTE and LTE-Advanced. Simulations show that SMST adopted in IEEE 802.16m outperforms other algorithms in terms of spectral efficiency, cell-edge performance, interference control, and trade-off control between sector-accumulated throughput and cell-edge user throughput. The SMST performance gain over FPC can be more than 40%展开更多
文摘This paper describes a method of calculating the Schur complement of a sparse positive definite matrix A. The main idea of this approach is to represent matrix A in the form of an elimination tree using a reordering algorithm like METIS and putting columns/rows for which the Schur complement is needed into the top node of the elimination tree. Any problem with a degenerate part of the initial matrix can be resolved with the help of iterative refinement. The proposed approach is close to the “multifrontal” one which was implemented by Ian Duff and others in 1980s. Schur complement computations described in this paper are available in Intel®Math Kernel Library (Intel®MKL). In this paper we present the algorithm for Schur complement computations, experiments that demonstrate a negligible increase in the number of elements in the factored matrix, and comparison with existing alternatives.
文摘The paper describes an efficient direct method to solve an equation Ax = b, where A is a sparse matrix, on the Intel®Xeon PhiTM coprocessor. The main challenge for such a system is how to engage all available threads (about 240) and how to reduce OpenMP* synchronization overhead, which is very expensive for hundreds of threads. The method consists of decomposing A into a product of lower-triangular, diagonal, and upper triangular matrices followed by solves of the resulting three subsystems. The main idea is based on the hybrid parallel algorithm used in the Intel®Math Kernel Library Parallel Direct Sparse Solver for Clusters [1]. Our implementation exploits a static scheduling algorithm during the factorization step to reduce OpenMP synchronization overhead. To effectively engage all available threads, a three-level approach of parallelization is used. Furthermore, we demonstrate that our implementation can perform up to 100 times better on factorization step and up to 65 times better in terms of overall performance on the 240 threads of the Intel®Xeon PhiTM coprocessor.
文摘With the increasing importance of cloud services worldwide, the cloud infrastructure and platform management has become critical for cloud service providers. In this paper, a novel architecture of intelligent server management framework is proposed. In this framework, the communication layer is based on the Extensible Messaging and Presence Protocol (XMPP), which was developed for instant messaging and has been proven to be highly mature and suitable for mobile and large scalable deployment due to its extensibility and efficiency. The proposed architecture can simplify server management and increase flexibility and scalability when managing hundreds of thousands of servers in the cloud era.
基金Supported by National Natural Science Foundation of China(Grant Nos.52375447,52305477 and 52105457)the Shandong Provincial Natural Science Foundation of China(Grant Nos.ZR2023QE057,ZR2024QE100 and ZR2024ME255)+2 种基金Qingdao Municipal Science and Technology Planning Park Cultivation Plan(Grant No.23-1-5-yqpy-17-qy)Shandong Provincial Science and Technology SMEs Innovation Capacity Improvement Project(Grant No.2022TSGC1115)the Special Fund of Taishan Scholars Project。
文摘Intelligent manufacturing(IM),a driving force behind the fourth industrial revolution,is reshaping the manufacturing sector by enhancing productivity,efficiency,and sustainability.Despite the rapid technological advancements in IM,comprehensive bibliometric reviews remain limited.This article systematically reviews the latest research in IM,addressing emerging hotspots,key technologies,and their applications across the entire product manufacturing cycle.Bibliometric analysis is employed to identify research trends visualize publication volume,collaboration patterns,research domains,co-citations,and emerging areas of interest.The article then examines key technologies supporting IM,including sensors,the Internet of Things(IoT),big data analytics,cloud computing,artificial intelligence(AI),digital twins,and virtual reality(VR)/augmented reality(AR).Furthermore,it explores the application of these technologies throughout the manufacturing cycle-from intelligent reliability design,material transportation and tracking,to intelligent planning and scheduling,machining and fabrication,monitoring and maintenance,quality inspection and control,warehousing and management,and sustainable green manufacturing—through specific case studies.Lastly,the article discusses future research directions,highlighting the increasing global market and the need for enhanced interdisciplinary collaboration,technological integration,computing power upgrades,and attention to security and privacy in IM.This study provides valuable insights for scholars and serves as a guide for future research and strategic investment decisions,offering a comprehensive view of the IM field.
基金supported by the National Key Research and Development Program of China (No.2021YFB3701000)the National Natural Science Foundation of China (Nos. 52401158, U21A2047, 52201129, 51821001,U2037601)+1 种基金the China Postdoctoral Science Foundation (No.2023M742219)the Postdoctoral Fellowship Program(Grade B) of CPSF (No. GZB20240419)
文摘Mg-Gd based alloys are an important class of high-performance Mg alloys.In this study,three Mg-Gd alloys with different gadolinium(Gd)contents:Mg-9.54Gd-0.40Zr(wt.%,G10 K),Mg-15.11Gd-0.35Zr(wt.%,G15 K)and Mg-19.67Gd-0.33Zr(wt.%,G20 K)were prepared by semicontinuous casting and subsequent solution and aging heat treatments.The role of Gd content on microstructures and mechanical properties of the Mg-Gd-Zr alloy is studied.All three as-cast alloys exhibit eutectic phases of Mg_(5)Gd,with the amount increasing as the Gd content rises.Mg_(5)Gd disappears after the solution heat treatment(the G10 K alloy solution-treated at 480℃ for 4 h,the G15 K alloy at 500℃ for 12 h and the G20 K alloy at 520℃ for 24 h,respectively).Aging heat treatment at 200℃ for 64 h after solution introduces numerous prismatic β' precipitates,with a significant increase in their area number density corresponding to increased Gd content.Additionally,the morphology of the β' precipitates exhibits distinct variations:the G10 K alloy is characterized by an enhanced aspect ratio.Consequently,the peak-aged G10 K alloy demonstrates superior strength-ductility synergy,with a yield strength(YS)of 216±1 MPa,an ultimate tensile strength(UTS)of 363±1 MPa,and an elongation(EL)of 8.7±0.6%.This study suggests that plasticity diminishes and precipitation strengthening is limited when the gadolinium content exceeds 15 wt.%.
文摘Mobile Edge Computing(MEC) is an emerging technology in 5G era which enables the provision of the cloud and IT services within the close proximity of mobile subscribers.It allows the availability of the cloud servers inside or adjacent to the base station.The endto-end latency perceived by the mobile user is therefore reduced with the MEC platform.The context-aware services are able to be served by the application developers by leveraging the real time radio access network information from MEC.The MEC additionally enables the compute intensive applications execution in the resource constraint devices with the collaborative computing involving the cloud servers.This paper presents the architectural description of the MEC platform as well as the key functionalities enabling the above features.The relevant state-of-the-art research efforts are then surveyed.The paper finally discusses and identifies the open research challenges of MEC.
文摘The effects of Bi addition on the growth of intermetallic compound (IMC) formation in Sn-3.8Ag-0.7Cu solder joints were investigated. The test samples were prepared by conventional surface mounting technology. To investigate the element diffusion and the growth kinetics of intermetallics formation in solder joint, isothermal aging test was performed at temperatures of 100, 150, and 190℃, respectively. The optical microscope (OM) and scanning electron microscope (SEM) were used to observe microstructure evolution of solder joint and to estimate the thickness and the grain size of the intermetallic layers. The IMC phases were identified by energy dispersive X-ray (EDX) and X-ray diffractometer (XRD). The results clearly show that adding about 1.0% Bi in Sn-Ag-Cu solder alloy system can refine the grain size of the IMC and inhibit the excessive IMC growth in solder joints, and therefore improve the reliability of the Pb-free solder joints. Through observation of the microstructural evolution of the solder joints, the mechanism of inhibition of IMC growth due to Bi addition was proposed.
文摘We synthesized NiO-loaded TiO2porous p-n junctions by electrophoretic enhanced micro arc oxidation（EEMAO） technique which is a relatively simple and new method for producing composite coatings.Phase structure,chemical composition,and surface morphology of the NiO—TiO2coatings were investigated by X-ray diffraction（XRD）,X-ray photoelectron spectroscopy（XPS）,and scanning electron microscopy（SEM） techniques,respectively.Photocatalytic efficiency of the samples was studied through measuring the decomposition rate of 4-chlorophenol under UV irradiation.Results showed that the coatings mainly consisted of anatase,rutile,and nickel oxide phases.It was observed that a finer surface morphology,i.e.smaller pores,was obtained at lower voltages.Besides,the amount of nickel oxide loaded to the TiO2host increased with the voltage.The NiO-TiO2composite coatings showed a higher photoactivity than pure TiO2coatings revealing the effective role of NiO in decreasing the recombination rate of photogenerated electrons and holes.The maximum photocatalytic reaction rate constants for TiO2and NiO—TiO2samples were obtained as 0.0064 and 0.0131 min-1,respectively.We also found that there was an optimum concentration of NiO where a maximum photocatalytic activity was achieved.A correlation between growth variables,structure,and photocatalytic efficiency was established.
基金supported by the European Union Horizon 2020 research and innovation program under CPSoSAware project(grant no.871738)by Science Foundation Ireland,grant no.12/RC/2289-P2,Insight Centre for Data Analytics。
文摘Artificial intelligence(AI)algorithms achieve outstanding results in many applicationdomains such as computer vision and natural language processing The performance ofAl models is the outcome of complex and costly model architecture design and trainingprocesses.Hence,it is paramount for model owners to protect their AI models frompiracy-model cloning,illegitimate distribution and use.IP protection mechanisms havebeen applied to Al models,and in particular to deep neural networks,to verify themodel ownership.State-of-the-art AI model ownership protection techniques have beensurveyed.The pros and cons of Al model ownership protection have been reported.The majonity of previous works are focused on watermarking,while more advancedmethods such fingerprinting and attestation are promising but not yet explored indepth.This study has been concluded by discussing possible research directions in thearea.
基金supported by the National Natural Science Foundation of China under Grant No. 60971036the National High Technology Research and Development Program of China under Grant No. 2008AA01Z104+1 种基金the Fundamental Research Funds for the Central Universities under Grant No. ZYGX2009Z004the New Century Excellent Talents in University under Grant No. NCET-08-0087
文摘To handle the effects of single event upsets（SEU）,which are common to computers in space radiation environment,a new fault-tolerant system with dual-module redundancy is proposed using dynamic reconfigurable technique of field programmable gate array（FPGA）. This system contains detection and backup alternative functions,that is,the self-detection and self-healing functions can be completed,and consequently a system design with low hardware redundancy and high resource utilization can be achieved successfully. So it can not only detect fault but also repair the fault effectively after failure. Hence,this method is especially practical to the dynamically reconfigurable computers based on FPGAs. Design methodology has been verified by Virtex-4 FPGA on Xilinx Ml403 development platform.
文摘With the ever-increasing range of video and audio applications in portable handheld devices, demand for high throughput in Wi-Fi networks is escalating. In this paper we introduce several novel features defined in next generation WLAN, termed as IEEE 802.11ax standard, and compare between the maximum throughputs received in IEEE 802.11ax and IEEE 802.11ac in a scenario where the AP continuously transmits to one station in the Single User mode. The comparison is done as a function of the modulation/coding schemes in use. In IEEE 802.11ax we consider two levels of frame aggregation. IEEE 802.11ax outperforms IEEE 802.11ac by about 29% and 48% in reliable and unreliable channels respectively.
文摘Coupled inductor is one appealing technology to improve transient response and reduce output decoupling significantly in interleaved multi-phase voltage regulators (VRs). One well known problem is that coupled inductor winding structure causes PCB routing path longer than discrete inductor design. This paper investigates possible PCB routing schemes for coupled inductor and conducts a fair and quantitative comparison with discrete inductor in a server VR design. Simulation and measurement are also conducted to verify the analysis.
文摘A miniaturized square resonator bandpass filter with circular stubs is designed, fabricated, and characterized. Analytical calculations were carried out to determine the critical filter parameters and the design was optimized using a 3D electromagnetic finite-element solver. The measured results were in good agreement with the designed results. The proposed filter exhibits significant improvement in bandwidth compared to the conventional square resonator bandpass filters.
文摘The processor is greatly hampered by the large dataset of picture or multimedia data.The logic of approximation hardware is moving in the direction of multimedia processing with a given amount of acceptable mistake.This study proposes various higher-order approximate counter-based compressor(CBC)using input shuffled 6:3 CBC.In the Wallace multiplier using a CBC is a significant factor in partial product reduction.So the design of 10-4,11-4,12-4,13-4 and 14-4 CBC are proposed in this paper using an input shuffled 6:3 compressor to attain two stage multiplications.The input shuffling aims to reduce the output combination of the 6:3 compressor from 64 to 27.Design of 15-4,10-4,9-4,and 7-3 CBCs are performed using the proposed 6:3 compressor and the results obtained are compared with the existing models.These existing models are constructed using multiplexers and 5-3 CBC.When compared to input shuffled 5-3 the proposed 6:3 compressor shows better results in terms of area,power and delay.An approximation is performed on the 6:3 compressor to further reduce the computational energy of the system which is optimal for multimedia applications.The major contribution of this work is the development of two stage multiplier using various proposed CBC.All designs of the approximate compressor(AC)and true compressor(TC)are analysed with 8 ×8 and 16 × 16 imagemultiplication.The proposed multipliers also provide adequate levels of accuracy,according to the MATLAB simulations,in addition to greater hardware efficiency.As the result approximate circuits over image processing shows the stunning performance in many deep learning network in the current research which is only oriented to multimedia.
文摘In this paper, we propose a novel uplink power control algorithm, SMST, for multiple-input multiple-output orthogonal frequency-division multiple access （MIMQ-OFDMA）.We perform an extensive system-level simulation to compare different uplink power control algorithms, including the FPC adopted in 3GPP LTE and LTE-Advanced. Simulations show that SMST adopted in IEEE 802.16m outperforms other algorithms in terms of spectral efficiency, cell-edge performance, interference control, and trade-off control between sector-accumulated throughput and cell-edge user throughput. The SMST performance gain over FPC can be more than 40%
