Convolutional neural networks(CNNs) exhibit excellent performance in the areas of image recognition and object detection, which can enhance the intelligence level of spacecraft. However, in aerospace, energetic partic...Convolutional neural networks(CNNs) exhibit excellent performance in the areas of image recognition and object detection, which can enhance the intelligence level of spacecraft. However, in aerospace, energetic particles, such as heavy ions, protons, and alpha particles, can induce single event effects(SEEs) that lead CNNs to malfunction and can significantly impact the reliability of a CNN system. In this paper, the MNIST CNN system was constructed based on a 28 nm systemon-chip(SoC), and then an alpha particle irradiation experiment and fault injection were applied to evaluate the SEE of the CNN system. Various types of soft errors in the CNN system have been detected, and the SEE cross sections have been calculated. Furthermore, the mechanisms behind some soft errors have been explained. This research will provide technical support for the design of radiation-resistant artificial intelligence chips.展开更多
Based on the mechanism of chip breaking and the principle of semi-solid thixomolding, the lathe process of AZ91D magnesium alloys chips used in semi-solid thixotropic injection molding process was studied. With three ...Based on the mechanism of chip breaking and the principle of semi-solid thixomolding, the lathe process of AZ91D magnesium alloys chips used in semi-solid thixotropic injection molding process was studied. With three kinds of turning tools, such as 31303C5, 31003C and 31303C, different chips were gotten. And by one tool with different lathe parameters, different chips were gotten. The results show that, under the needed condition of the thixotropic injection molding machine, the ideal chips are gotten and the size of magnesium alloy chips must be about 35mm, and the turning tool is chosen, whose chip breaker groove is narrower and the depth of cutting is more than 3mm as well as the amount of feed is larger than 0.3mm. The deformation occurs on the microstructure of the chips, and the residual stress is important to the later microstructure of semi-solid state in injection molding.展开更多
A new method of manufacturing micro-flow channels on graphite composite bipolar plate(GCBPP) microplaning using specially designed multi-tooth tool is proposed. In this method, several or even dozens of parallel micro...A new method of manufacturing micro-flow channels on graphite composite bipolar plate(GCBPP) microplaning using specially designed multi-tooth tool is proposed. In this method, several or even dozens of parallel micro-flow channels ranging from 100 μm to 500 μm in width can be produced simultaneously. But, edge chippings easily occur on the rib surface of GCBPP during microplaning due to brittleness of graphite composites. Experimental results show that edge chippings result in the increase of contact resistance between bipolar plate and carbon paper at low compaction force. While the edge chippings scarcely exert influence on the contact resistance at high compaction force. Contrary to conventional view, the edge chippings can significantly improve performance of microfuel cell and big edge chippings outperform small edge chippings. In addition, the influence of technical parameters on edge chippings was investigated in order to obtain big, but not oversized edge chippings.展开更多
In the Paper,the author introduces an embedded design verification test based on specific chips to solve the technical problems of microwave circuit test and fault diagnosis.The author explains embedded design of micr...In the Paper,the author introduces an embedded design verification test based on specific chips to solve the technical problems of microwave circuit test and fault diagnosis.The author explains embedded design of microwave circuit modules and approach of hardware design and software design,and finally verifies the embedded design of microwave circuit modules based on specific chips.展开更多
A sequential injection analysis (SIA) system based on polydimethylsiloxane (PDMS) chip with integrated pneumatic-actuated valves was developed. A novel SIA operation mode using multiphase laminar flow effect and pneum...A sequential injection analysis (SIA) system based on polydimethylsiloxane (PDMS) chip with integrated pneumatic-actuated valves was developed. A novel SIA operation mode using multiphase laminar flow effect and pneumatic microvalve control was proposed. The sample and reagent solutions were synchronously loaded and injected in the chip-based sample injection module instead of multi-step sequential injection by a multiposition valve and a reciprocating pump as in conventional SIA system. The sample and reagent injection volumes were reduced to ca. 1.1 nL. The present system has the advantages of simple structure, fast and convenient operation, low sample and reagent consumption, and high degree of integration and automation. The system operation conditions were optimized using fluorescein as model sample. Its feasibility in biological analysis was preliminarily demonstrated in enzyme inhibition assay.展开更多
A high-throughput sample introduction system for chip-based microfluidic analysis was developed. The sampling system was composed of a capillary sampling probe attached to the microchip channel and an array of horizon...A high-throughput sample introduction system for chip-based microfluidic analysis was developed. The sampling system was composed of a capillary sampling probe attached to the microchip channel and an array of horizontally positioned micro-sample vials with slits fabricated on the bottom of each vial for pass-through of the sampling probe. The micro-sample vials array was fixed on a homebuilt platform capable of moving linearly under computer control. Sample introduction was performed by linearly moving the array of vials,allowing the probe inlet to sequentially enter the solutions in the vials through the slits. The use of a slotted vial array in the sample introduction system allowed convenient and rapid sample change with low sample volume in 10\+\{-9\} L range and high sampling frequency without requiring mechanical valves and pumps. The system was applied to achieve continuously automated sample change in a chip-based flow injection analysis system with absorption detection by using a liquid-core waveguide capillary flow-cell. High sampling throughput of 600 h -1 was obtained in this system with a sample consumption of only 4.3 nL for each cycle.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.12305303)the Natural Science Foundation of Hunan Province of China(Grant Nos.2023JJ40520,2021JJ40444,and 2019JJ30019)+3 种基金the Research Foundation of Education Bureau of Hunan Province of China(Grant No.20A430)the Science and Technology Innovation Program of Hunan Province(Grant No.2020RC3054)the Natural Science Basic Research Plan in the Shaanxi Province of China(Grant No.2023-JC-QN-0015)the Doctoral Research Fund of University of South China。
文摘Convolutional neural networks(CNNs) exhibit excellent performance in the areas of image recognition and object detection, which can enhance the intelligence level of spacecraft. However, in aerospace, energetic particles, such as heavy ions, protons, and alpha particles, can induce single event effects(SEEs) that lead CNNs to malfunction and can significantly impact the reliability of a CNN system. In this paper, the MNIST CNN system was constructed based on a 28 nm systemon-chip(SoC), and then an alpha particle irradiation experiment and fault injection were applied to evaluate the SEE of the CNN system. Various types of soft errors in the CNN system have been detected, and the SEE cross sections have been calculated. Furthermore, the mechanisms behind some soft errors have been explained. This research will provide technical support for the design of radiation-resistant artificial intelligence chips.
文摘Based on the mechanism of chip breaking and the principle of semi-solid thixomolding, the lathe process of AZ91D magnesium alloys chips used in semi-solid thixotropic injection molding process was studied. With three kinds of turning tools, such as 31303C5, 31003C and 31303C, different chips were gotten. And by one tool with different lathe parameters, different chips were gotten. The results show that, under the needed condition of the thixotropic injection molding machine, the ideal chips are gotten and the size of magnesium alloy chips must be about 35mm, and the turning tool is chosen, whose chip breaker groove is narrower and the depth of cutting is more than 3mm as well as the amount of feed is larger than 0.3mm. The deformation occurs on the microstructure of the chips, and the residual stress is important to the later microstructure of semi-solid state in injection molding.
基金Project(51075155)supported by the National Natural Science Foundation of ChinaProject(2013ZZ017)supported by the Fundamental Research Funds for the Central Universities,China
文摘A new method of manufacturing micro-flow channels on graphite composite bipolar plate(GCBPP) microplaning using specially designed multi-tooth tool is proposed. In this method, several or even dozens of parallel micro-flow channels ranging from 100 μm to 500 μm in width can be produced simultaneously. But, edge chippings easily occur on the rib surface of GCBPP during microplaning due to brittleness of graphite composites. Experimental results show that edge chippings result in the increase of contact resistance between bipolar plate and carbon paper at low compaction force. While the edge chippings scarcely exert influence on the contact resistance at high compaction force. Contrary to conventional view, the edge chippings can significantly improve performance of microfuel cell and big edge chippings outperform small edge chippings. In addition, the influence of technical parameters on edge chippings was investigated in order to obtain big, but not oversized edge chippings.
文摘In the Paper,the author introduces an embedded design verification test based on specific chips to solve the technical problems of microwave circuit test and fault diagnosis.The author explains embedded design of microwave circuit modules and approach of hardware design and software design,and finally verifies the embedded design of microwave circuit modules based on specific chips.
基金supported by the National Natural Science Foundation of China (20825517, 20890020)Ministry of Science and Technology of China (2007CB714503)
文摘A sequential injection analysis (SIA) system based on polydimethylsiloxane (PDMS) chip with integrated pneumatic-actuated valves was developed. A novel SIA operation mode using multiphase laminar flow effect and pneumatic microvalve control was proposed. The sample and reagent solutions were synchronously loaded and injected in the chip-based sample injection module instead of multi-step sequential injection by a multiposition valve and a reciprocating pump as in conventional SIA system. The sample and reagent injection volumes were reduced to ca. 1.1 nL. The present system has the advantages of simple structure, fast and convenient operation, low sample and reagent consumption, and high degree of integration and automation. The system operation conditions were optimized using fluorescein as model sample. Its feasibility in biological analysis was preliminarily demonstrated in enzyme inhibition assay.
文摘A high-throughput sample introduction system for chip-based microfluidic analysis was developed. The sampling system was composed of a capillary sampling probe attached to the microchip channel and an array of horizontally positioned micro-sample vials with slits fabricated on the bottom of each vial for pass-through of the sampling probe. The micro-sample vials array was fixed on a homebuilt platform capable of moving linearly under computer control. Sample introduction was performed by linearly moving the array of vials,allowing the probe inlet to sequentially enter the solutions in the vials through the slits. The use of a slotted vial array in the sample introduction system allowed convenient and rapid sample change with low sample volume in 10\+\{-9\} L range and high sampling frequency without requiring mechanical valves and pumps. The system was applied to achieve continuously automated sample change in a chip-based flow injection analysis system with absorption detection by using a liquid-core waveguide capillary flow-cell. High sampling throughput of 600 h -1 was obtained in this system with a sample consumption of only 4.3 nL for each cycle.
