Owing to the dramatic mobile IP growth,the emerging Internet of Things,and cloud-based applications,wireless networking is witnessing a paradigm shift.By fully exploiting spatial degrees of freedom,massive multiple-in...Owing to the dramatic mobile IP growth,the emerging Internet of Things,and cloud-based applications,wireless networking is witnessing a paradigm shift.By fully exploiting spatial degrees of freedom,massive multiple-input-multiple-output(MIMO) systems promise significant gains in data rates and link reliability.Although the research community has recognized the theoretical benefits of these systems,building the hardware of such complex systems is a challenge in practice.This paper presents a time division duplex(TDD)-based 128-antenna massive MIMO prototype system from theory to reality.First,an analytical signal model is provided to facilitate the setup of a feasible massive MIMO prototype system.Second,a link-level simulation consistent with practical TDDbased massive MIMO systems is conducted to guide and validate the massive MIMO system design.We design and implement the TDDbased 128-antenna massive MIMO prototype system with the guidelines obtained from the link-level simulation.Uplink real-time video transmission and downlink data transmission under the configuration of multiple single-antenna users are achieved.Comparisons withstate-of-the-art prototypes demonstrate the advantages of the proposed system in terms of antenna number,bandwidth,latency,and throughput.The proposed system is also equipped with scalability,which makes the system applicable to a wide range of massive scenarios.展开更多
Overview The growing trends for convergence of functionality and divergence in standards are creating new opportunities for test engineers to develop next generation test systems that greatly contribute to acceleratin...Overview The growing trends for convergence of functionality and divergence in standards are creating new opportunities for test engineers to develop next generation test systems that greatly contribute to accelerating the product devel- opment cycle as well as maintaining test system longevity because they are possible to upgrade to the rapid techno- logical advancement.The approach to test system devel-展开更多
IntroductionThe PXI industry standard has quickly gained adoption and grown in prevalence in automated test systems since its release in 1998. PXI is being selected as the platform of choice for thousands of applicati...IntroductionThe PXI industry standard has quickly gained adoption and grown in prevalence in automated test systems since its release in 1998. PXI is being selected as the platform of choice for thousands of applications, from areas such as military and aerospace, consumer electronics, and communications, to process control and industrial automation. One of the key elements driving the rapid adoption of PXI is its use of PCI in the communication backplane. Now, as the commercial PC industry drastically improves the available bus bandwidth by evolving PCI to PCI Express, PXI has the ability to meet even more application needs by integrating PCI Express into the PXI standard.展开更多
An optimal test method for paint is proposed; additionally, the Field and Laboratory Emission Cell (FLEC) method used in Europe is applied as a substitute for the 20 L small chamber method. The emission factors of t...An optimal test method for paint is proposed; additionally, the Field and Laboratory Emission Cell (FLEC) method used in Europe is applied as a substitute for the 20 L small chamber method. The emission factors of total volatile organic compounds (TVOC) and formaldehyde from oil-based paint, emulsion paint, and water-dispersion paint with a coating weight of 300 g/m2, cured for 24/48 hours, were measured using the 20 L small chamber method. The emission rate of TVOC and formaldehyde from all paints began to stabilize after approximately 7 days after 24/48 hours of curing even though Korean standards stipulate that paint should be measured and analyzed after the third day of application. The emission factor of TVOC and formaldehyde from oil-based, emulsion, and water-dispersion paints were also measured using the FLEC method. There was good correlation between the 20 L small chamber method and the FLEC method for oil-based, emulsion, and water-dispersion paint emissions. With the FLEC method, using paints prepared under identical conditions, the emission rate was stable 24 hours after installation of samples because the air flow rate of FLEC is much higher than that of a 20 L small chamber, and the relative cell volume of FLEC is much smaller than that of a 20 L small chamber.展开更多
This paper discusses about the purity of strengthened pure platinum wire and the development method of platinum micro wire, in order to solve the difficulties of low tensile strength, easy to break, and low rate of mi...This paper discusses about the purity of strengthened pure platinum wire and the development method of platinum micro wire, in order to solve the difficulties of low tensile strength, easy to break, and low rate of micro wire. And it contrasts some performance of strengthened pure platinum wire and sponge Pt wire. The researches draw a conclusion that the thermoelectric properties of strengthened pure platinum micro wire was in accordance with national standards and satisfied users' requirements.展开更多
Multicore processing is generating considerable buzz with in the PC industry,largely because both Intel and AMD have released initial versions of their own multicore processors.These first multicore processors contain...Multicore processing is generating considerable buzz with in the PC industry,largely because both Intel and AMD have released initial versions of their own multicore processors.These first multicore processors contain two cores,or computing engines,located in one physical processor-hence the name dual-core processors.展开更多
基金supported in part by the National Science Foundation(NSFC) for Distinguished Young Scholars of China with Grant 61625106the National Natural Science Foundation of China under Grant 61531011the Hong Kong,Macao and Taiwan Science and Technology Cooperation Program of China(2016YFE0123100)
文摘Owing to the dramatic mobile IP growth,the emerging Internet of Things,and cloud-based applications,wireless networking is witnessing a paradigm shift.By fully exploiting spatial degrees of freedom,massive multiple-input-multiple-output(MIMO) systems promise significant gains in data rates and link reliability.Although the research community has recognized the theoretical benefits of these systems,building the hardware of such complex systems is a challenge in practice.This paper presents a time division duplex(TDD)-based 128-antenna massive MIMO prototype system from theory to reality.First,an analytical signal model is provided to facilitate the setup of a feasible massive MIMO prototype system.Second,a link-level simulation consistent with practical TDDbased massive MIMO systems is conducted to guide and validate the massive MIMO system design.We design and implement the TDDbased 128-antenna massive MIMO prototype system with the guidelines obtained from the link-level simulation.Uplink real-time video transmission and downlink data transmission under the configuration of multiple single-antenna users are achieved.Comparisons withstate-of-the-art prototypes demonstrate the advantages of the proposed system in terms of antenna number,bandwidth,latency,and throughput.The proposed system is also equipped with scalability,which makes the system applicable to a wide range of massive scenarios.
文摘Overview The growing trends for convergence of functionality and divergence in standards are creating new opportunities for test engineers to develop next generation test systems that greatly contribute to accelerating the product devel- opment cycle as well as maintaining test system longevity because they are possible to upgrade to the rapid techno- logical advancement.The approach to test system devel-
文摘IntroductionThe PXI industry standard has quickly gained adoption and grown in prevalence in automated test systems since its release in 1998. PXI is being selected as the platform of choice for thousands of applications, from areas such as military and aerospace, consumer electronics, and communications, to process control and industrial automation. One of the key elements driving the rapid adoption of PXI is its use of PCI in the communication backplane. Now, as the commercial PC industry drastically improves the available bus bandwidth by evolving PCI to PCI Express, PXI has the ability to meet even more application needs by integrating PCI Express into the PXI standard.
基金Supported by the National Research Foundation of Korea (NRF) by the Korea Government (MEST) (No. 2011-0001031)
文摘An optimal test method for paint is proposed; additionally, the Field and Laboratory Emission Cell (FLEC) method used in Europe is applied as a substitute for the 20 L small chamber method. The emission factors of total volatile organic compounds (TVOC) and formaldehyde from oil-based paint, emulsion paint, and water-dispersion paint with a coating weight of 300 g/m2, cured for 24/48 hours, were measured using the 20 L small chamber method. The emission rate of TVOC and formaldehyde from all paints began to stabilize after approximately 7 days after 24/48 hours of curing even though Korean standards stipulate that paint should be measured and analyzed after the third day of application. The emission factor of TVOC and formaldehyde from oil-based, emulsion, and water-dispersion paints were also measured using the FLEC method. There was good correlation between the 20 L small chamber method and the FLEC method for oil-based, emulsion, and water-dispersion paint emissions. With the FLEC method, using paints prepared under identical conditions, the emission rate was stable 24 hours after installation of samples because the air flow rate of FLEC is much higher than that of a 20 L small chamber, and the relative cell volume of FLEC is much smaller than that of a 20 L small chamber.
文摘This paper discusses about the purity of strengthened pure platinum wire and the development method of platinum micro wire, in order to solve the difficulties of low tensile strength, easy to break, and low rate of micro wire. And it contrasts some performance of strengthened pure platinum wire and sponge Pt wire. The researches draw a conclusion that the thermoelectric properties of strengthened pure platinum micro wire was in accordance with national standards and satisfied users' requirements.
文摘Multicore processing is generating considerable buzz with in the PC industry,largely because both Intel and AMD have released initial versions of their own multicore processors.These first multicore processors contain two cores,or computing engines,located in one physical processor-hence the name dual-core processors.