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Design and verification of an FPGA programmable logic element based on Sense-Switch pFLASH

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Frontiers of Information Technology & Electronic Engineering 2024年第4期25卷 485-499页

作者： Zhengzhou cao Guozhu LIU yanfei ZHANG Yueer SHAN Yuting XU No.58 Research Institute China Electronics Technology Group CorporationWuxi 214035China

This paper proposes a kind of programmable logic element(PLE)based on Sense-Switch pFLASH technology.By programming Sense-Switch pFLASH,all three-bit look-up table(LUT3)functions,partial four-bit look-up table(LUT4)functions,latch functions,and d flip flop(DFF)with enable and reset functions can be realized.Because PLE uses a choice of operational logic(COOL)approach for the operation of logic functions,it allows any logic circuit to be implemented at any ratio of combinatorial logic to register.This intrinsic property makes it close to the basic application specific integrated circuit(ASIC)cell in terms of fine granularity,thus allowing ASIC-like cell-based mappers to apply all their optimization potential.By measuring Sense-Switch pFLASH and PLE circuits,the results show that the“on”state driving current of the Sense-Switch pFLASH is about 245.52μA,and that the“off”state leakage current is about 0.1 pA.The programmable function of PLE works normally.The delay of the typical combinatorial logic operation AND3 is 0.69 ns,and the delay of the sequential logic operation DFF is 0.65 ns,both of which meet the requirements of the design technical index.

关键词： Field programmable gate array(FPGA) Programmable logic element(PLE) Boolean logic operation Look-up table Sense-Switch pFLASH Threshold voltage

Effects of Primary Carbide Size and Type on the Sliding Wear and Rolling Contact Fatigue Properties of M50 Bearing Steel

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金属学报:英文版 2023年第8期36卷 1336-1352页

作者： Liqi Yang Weihai Xue Siyang Gao yanfei cao Hongwei Liu Deli Duan Dianzhong Li Shu Li Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China

The influences of primary carbide size and type on the sliding wear behavior and rolling contact fatigue (RCF) properties of M50 bearing steel were systematically investigated under oil lubrication condition. A major breakthrough was achieved in the influence of primary carbide on tribological behavior. The opposite effect brought by primary carbide size on the sliding wear resistance and RCF life of M50 bearing steel was determined. Wear resistance increased with an increase in the studied primary carbide size, whereas RCF life decreased significantly. Compared with the 0 R and R positions with a relatively small carbide size, the wear volume of the 1/2 R position with a large carbide size was the smallest. Compared with the 0 R and R positions, the L10 life of the 1/2 R position decreased by 82.7% and 84.8%, respectively. On the basis of the statistical correlation between primary carbide size and the two tribological properties, a critical maximum carbide size of 5-10 μm was proposed to achieve optimal tribological performance. This research suggests that the equivalent diameter of the primary carbide should be controlled to be smaller than 10 μm, but further decreasing primary carbide size to less than 5 μm is unnecessary. The influence of primary carbide type in M50 bearing steel on sliding wear resistance was also discussed. Results indicate that the MC-type carbides with higher elastic modulus and microhardness exhibit better wear resistance than the M2C-type carbides.

关键词： Carbide size Carbide type Sliding wear Rolling contact fatigue M50 bearing steel

Analysis of the thermal performance of the novel assembled Chinese solar greenhouse with a modular soil wall in winter of Yinchuan,China

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International Journal of Agricultural and Biological Engineering 2022年第5期15卷 70-77页

作者： yanfei cao Hongjun Xu Miao Shi Xueyan Zhang Yahong Zhang Zhirong Zou College of Horticulture Northwest A&F UniversityYangling 712100ShaanxiChina Key Laboratory of Protected Horticulture Engineering in Northwest Ministry of Agriculture and Rural AffairsYangling 712100ShaanxiChina College of Horticulture Xinjiang Agricultural UniversityUrumqi 830052China School of Agriculture Ningxia UniversityYinchuan 750021China

In order to improve the thermal insulation and storage performance of Chinese solar greenhouses in winter,a novel assembled Chinese solar greenhouse(ACSG)without energy supplement in cold climatic areas was designed to evaluate and compare its thermal performance with that of conventional Chinese solar greenhouse(CSG).The thermal properties of both greenhouses were tested in field on cold winter days in Ningxia,China.The results indicated that the land utilization rate of ACSG was 19.3%higher than that of CSG.On a typical sunny day(the lowest outdoor temperature was−22.0℃)and typical cloudy day(the lowest outdoor temperature was−19.7℃)during the experiment,the minimum indoor temperature of ACSG was respectively 1.7℃and 2.0℃higher than that of CSG.The results for 24 consecutive days(the average outdoor daily minimum air temperature was−19.0℃)showed that the average minimum indoor temperature of ACSG was 1.4℃higher than that of CSG(p<0.05).The modular soil wall attached with colored steel polystyrene boards would be exploited as the north wall of CSG in Yinchuan area.

关键词： thermal performance solar greenhouse north wall composite wall structure soil block

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美国交通系统公共艺术规划策略与启示

规划师 2024年第6期40卷 152-158页

作者：王燕斐曹汝平上海工程技术大学艺术设计学院

长期以来,我国公共艺术的规划主要集中在城市雕塑领域,交通管理部门缺乏对交通系统公共艺术的专项规划,导致交通项目中的公共艺术实践成为“无源之水,无本之木”。以美国为研究对象,总结归纳其交通系统公共艺术规划的发展阶段、具体策略... 详细信息

长期以来,我国公共艺术的规划主要集中在城市雕塑领域,交通管理部门缺乏对交通系统公共艺术的专项规划,导致交通项目中的公共艺术实践成为“无源之水,无本之木”。以美国为研究对象,总结归纳其交通系统公共艺术规划的发展阶段、具体策略,认为我国有必要针对交通领域公共艺术的实际问题给予制度层面的保障,尽快出台公共艺术专项规划政策及规划规范,明确公众参与的定义及细则,实现“专职专项、分级分类、有效参与”的规划,以支持我国交通系统公共艺术的永续发展和公众参与的有效落实。

关键词：公共艺术规划交通系统美国

Application performances of two greenhouses with new types of backwall in Yangling,China

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International Journal of Agricultural and Biological Engineering 2022年第3期15卷 62-71页

作者： Yachen Sun Haotian Wang Chenmeng Zhu Hongyi Lyu Xuanhe Zhang yanfei cao Jianming Li Zhirong Zou Encai Bao College of Architecture and Urban Planning Tongji UniversityShanghai 200092China Key Laboratory of Protected Horticultural Engineering in Northwest Ministry of Agriculture and Rural AffiairsDepartment of HorticultureNorthwest A&F UniversityYangling 712100ShaanxiChina Office of Academic Affairs Fudan UniversityShanghai 200433China Institute of Agricultural Facilities and Equipment Jiangsu Academy of Agricultural ScienceKey Laboratory of Protected Agriculture Engineering in the Middle and Lower Reaches of Yangtze RiverMinistry of Agriculture and Rural AffairsNanjing 210014China

In order to investigate the application performances of the solar greenhouses with new types of backwall(greenhouse W_(2),and greenhouse W_(3))and the ordinary clay brick backwall greenhouse(greenhouse W_(1)),and provide a theoretical basis for the construction of solar greenhouse in Yangling Demonstration Zone,Shaanxi,China,two greenhouses with different new types of backwall were designed.The backwall of one of them was built with lightweight aggregate concrete block(greenhouse W_(2))and that of the other one was assembled with a row of sand-filled cement pipes(greenhouse W_(3)).The tested greenhouses were constructed in Yangling Demonstration Zone.Based on the data collected on typical sunny and cloudy days,the indoor temperature,inside wall temperature,and the heat flow of the greenhouses with new types of backwall were compared with those detected in the ordinary clay brick backwall solar greenhouse,and the tested results were numerically simulated.According to the comparison of the physiological indicators of tomatoes planted in the greenhouses and the construction costs,the greenhouse type with the best practicability was found.The results indicated that:The average air temperature in greenhouses W_(1),W_(2),and W_(3)and outside was 15.1℃,15.9℃,17.3℃,and−0.4℃ on the night of a sunny day,and the air temperature in W_(3)was the highest.The average air temperature in greenhouses W_(1),W_(2),and W_(3)and outside were 9.5℃,13.3℃,11.0℃,and−5.5℃ on the night of a cloudy day,the air temperature in W_(2)was the highest.In the depth of 0-330 mm from the interface of the backwalls,the walls were obviously affected by the solar radiation,and the temperature changed greatly.The wall temperature on the sunny days exhibited an ascending order of W_(1),W_(2),W_(3),while on the cloudy days was in the ascending order of W_(1),W_(3),W_(2).The wall of W_(3)absorbed the most heat during the daytime and released the most heat at night on the sunny day,while W_(2)exhibited the second most heat absorption during the daytime,howev

关键词： application performances solar greenhouse backwall temperature

Solidification microstructure of Cr4Mo4V steel forged in the semi-solid state

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Journal of Materials Science & Technology 2020年第3期38卷 170-182页

作者： Weifeng Liu yanfei cao Yifeng Guo Mingyue Sun Bin Xu Dianzhong Li Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China College of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

Semi-solid forging of iron-based alloys during solidification has unique characteristics distinct from those of the classical hot forging.With the aim of acquiring precise knowledge concerning the microstructural evolution of bearing steel Cr4 Mo4 V in this process,a series of semi-solid forging experiments were carried out in which samples were wrapped in a designed pure iron sheath.The effects of forging temperature and forging reduction on the grain morphology and liquid flow behavior were investigated,respectively.By forging solidifying metal(FSM),bulky primary dendrites were broken and spheroidal grains with an average shape factor of 0.87 were obtained at 1360?C.With the decreasing forging temperature to 1340?C,the microstructural homogeneity can be improved.On the other hand,it shows that a higher forging reduction(50%)is essential for the spheroidization of grains and elimination of liquid segregation.Those microstructural characteristics are related to different motion mechanisms of solid and liquid phases at different forging temperatures.Additionally,the effect of semi-solid forging on the eutectic carbides was also investigated,and the results demonstrate that the higher diffusion capacity and less liquid segregation jointly lower the large eutectic carbides and consequently cause its uniform distribution during FSM.

关键词： Solidification Semi-solid forging Microstructure Eutectic carbides

Effects of Rare Earth elements on microstructure evolution and mechanical properties of 718H pre-hardened mold steel

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Journal of Materials Science & Technology 2020年第15期47卷 245-256页

作者： Hanghang Liu Paixian Fu Hongwei Liu yanfei cao Chen Sun Ningyu Du Dianzhong Li Shenyang National Laboratory for Materials Science Shenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

718 H Pre-ha rdened mold steels with diffe rent Rare Earth(RE) contents were prepared to investigate the influence of RE on microstructure evolution and mechanical properties through a series of experiments and theoretical analysis.The results indicated that the toal oxygen(T.O) content decreased from 15 ppm to 6 ppm with 0.022 wt% RE addition,which is attributed to the active chemical properties of RE elements.For test steels,RE additions of 0.012 wt% and 0.022 wt% were significantly effective for refining inclusions by eliminating 11.5% large-sized inclusions with diameter exceeding 10 μm compared with that of ORE steel.RE addition contributed to modify irregular MnS and Al2 O3 inclusions into ellipsoidal RE-inclusions(RE2 O,RES,RE2 O2 S and REAlO3).The purification of molten steel and the modification of inclusions by RE treatment have significant effects on improvement of the fatigue crack growth tests(FCG) inhibition ability and impact energy as well as the isotropy.However,excessive addition of RE elements(0.07 wt%)seriously reduced the impact energy,ultimate tensile strength and FCG inhibition ability due to rapidly increase of the volume fraction of large-sized inclusions.In addition to the inclusions formed by RE treatment,trace solid solution RE atoms improve the stability of undercooled austenite,resulting in the transformation region of bainite and perlite of 0.07 RE steel shifting to the bottom right and prolonging the incubation period compared with that of ORE steel.

关键词： 718H steel Rare Earth Inclusion evolution Phase transformation Mechanical properties

Revisiting dynamics and models of microsegregation during polycrystalline solidification of binary alloy

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Journal of Materials Science & Technology 2021年第15期74卷 155-167页

作者： Tongzhao Gong Yun Chen Shanshan Li yanfei cao Dianzhong Li Xing-Qiu Chen Guillaume Reinhart Henri Nguyen-Thi Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei230026China Aix Marseille Univ Universite de ToulonCNRSIM2NPMarseilleFrance

Microsegregation formed during solidification is of great importance to material properties.The conventional Lever rule and Scheil equation are widely used to predict solute segregation.However,these models always fail to predict the exact solute concentration at a high solid fraction because of theoretical assumptions.Here,the dynamics of microsegregation during polycrystalline solidification of refined Al-Cu alloy is studied via two-and three-dimensional quantitative phase-field simulations.Simulations with different grain refinement level,cooling rate,and solid diffusion coefficient demonstrate that solute segregation at the end of solidification(i.***.when the solid fraction is close to unit)is not strongly correlated to the grain morphology and back diffusion.These independences are in accordance with the Scheil equation which only relates to the solid fraction,but the model predicts a much higher liquid concentration than simulations.Accordingly,based on the quantitative phase-field simulations,a new analytical microsegregation model is derived.Unlike the Scheil equation or the Lever rule that respectively overestimates or underestimates the liquid concentration,the present model predicts the liquid concentration in a pretty good agreement with phase-field simulations,particularly at the late solidification stage.

关键词： Microsegregation Grain refinement Cooling rate Back diffusion Phase-field method

Influence of thermodynamic disfigurement on the convective heat transfer of solar greenhouse

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International Journal of Agricultural and Biological Engineering 2020年第4期13卷 55-60页

作者： Yachen Sun yanfei cao Haotian Wang Changji Zhou Jinxin Xiao Chengyao Jiang Jianming Li Encai Bao Zhirong Zou Key Laboratory of Protected Horticultural Engineering in Northwest Ministry of Agriculture and Rural AffairsDepartment of HorticultureNorthwest A&F UniversityYangling 712100ShaanxiChina Academy of Agricultural Planning and Engineering Ministry of Agriculture and Rural AffairsBeijing 100125China Institute of Agricultural Facilities and Equipment Jiangsu Academy of Agricultural SciencesKey Laboratory of Protected Agriculture Engineering in the Middle and Lower Reaches of Yangtze RiverMinistry of Agriculture and Rural AffairsNanjing 210014China

Solar greenhouse is a typical greenhouse without any additional heating system,which has developed rapidly in Northern China.However,due to the construction quality,management methods,especially the long-term use and other factors,there are usually different degrees of thermodynamic disfigurements in the envelop enclosure of solar greenhouse.The purpose of this study was to investigate the influences of thermodynamic disfigurement on the temperature distribution and convective heat transfer of solar greenhouse.In this study,the east and west compartments of a typical solar greenhouse which is located in Yangling,China(108°4′E,34°16′N)were tested.The air temperature of each compartment was collected using temperature recorders,and the thermal infrared images of different compartment envelopes were obtained by a thermal infrared imager on a typical cloudy day.Convective heat transfer coefficients and heat flux densities of different compartment envelopes in the solar greenhouse were calculated.The results showed that the temperature difference can be displayed in the thermal infrared images of compartment envelopes,the surface temperature of the front roof was the lowest,followed by the back roof,the wall surface temperature was the highest.The minimum average surface temperature of the front roof in the eastern compartment was only 3.8℃,which was 6.8℃ and 9.2℃ lower than the average surface temperature of the back roof and back wall,respectively.The surface average temperature of thermodynamic disfigurements located at the bottom of the south side in the front roof of the eastern compartment,whose area accounted for 16.5%of the total front roof in the eastern compartment,was only 5.4℃.Compared with non-thermodynamic disfigurement,the average convective heat transfer coefficient and heat flux density of thermodynamic disfigurements in the front roof of the eastern compartment were increased by 20.3%and 110.3%,respectively.The average air temperature in the eastern compartment was 3.5℃ lower than the average air tem

关键词： solar greenhouse thermodynamic disfigurement convective heat transfer thermal infrared image