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Development of space-based diffractive telescopes Review Article
Wei Zhao, Xin Wang, Hua Liu, Zi-feng Lu, Zhen-wu Lu,wangxin971241@163.com,liuhua_rain@aliyun.com
Frontiers of Information Technology & Electronic Engineering 2020, Volume 21, Issue 6, Pages 809-962 doi: 10.1631/FITEE.1900529
Keywords： 薄膜衍射光学元件；衍射望远系统；超大口径
Xiong-bin PENG, Guo-fang GONG, Hua-yong YANG, Hai-yang LOU, Wei-qiang WU, Tong LIU
Frontiers of Information Technology & Electronic Engineering 2017, Volume 18, Issue 10, Pages 1624-1634 doi: 10.1631/FITEE.1601104
Keywords： Large-scale reflecting telescope Quantitative feedback theory Electro-hydraulic position control system Micron-level position control capability System identification Robust stability
With Great Expectations, Webb Telescope Finally Lifts Off
Mitch Leslie
Engineering 2022, Volume 11, Issue 4, Pages 3-5 doi: 10.1016/j.eng.2022.02.002
Neutron Diffraction Investigation of the DyFe11Ti Magnetic Structure and Its Spin Reorientations Article
Olivier Isnard, Eder J. Kinast
Engineering 2020, Volume 6, Issue 2, Pages 153-157 doi: 10.1016/j.eng.2019.11.009
In this article, we report on the magnetic structure of DyFe11Ti and its thermal evolution as probed by neutron powder diffraction. A thermodiffraction technique was used to follow the temperature dependence of the magnetic moments, as well as their orientation. The Dy and Fe moments were coupled to each other in an antiparallel manner to form a ferrimagnet, where the easy magnetization direction at 2 K was the [110] axis in the basal (a, b) plane. This magnetic structure underwent two successive spin reorientation phenomena with increasing temperature. A large Dy magnetic moment of 9.7 μB was obtained at low temperatures, and the magnitude decreased rapidly to 7.5 μB at 200 K. The largest Fe magnetic moment was observed on the Fe 8i position. A ThMn12-type crystal structure was preserved in the studied temperature range, despite the large changes of the magnetic structure. A sharp tilt was observed at the first-order spin reorientation, TSR1; the angle between the easy magnetization axis and the crystal c axis was reduced from 90° at 2 K to about 20° at 200 K (where c is the easy axis above 200 K); and the Dy and Fe magnetic moments maintained an antiparallel coupling.
Keywords： Neutron diffraction Magnetic phase diagram Crystal structure
Xiaoping Wang, Weiwei Dong, Peng Zhang, Haoqi Tang, Lanting Zhang, Tieying Yang, Peng Liu, Hong Wang, X.-D. Xiang
Engineering 2022, Volume 10, Issue 3, Pages 81-88 doi: 10.1016/j.eng.2021.05.023
High-throughput powder X-ray diffraction (XRD) with white X-ray beam and an energy-dispersive detector array are demonstrated in this work on a CeO2 powder sample on a bending magnet synchrotron beamline at the Shanghai Synchrotron Radiation Facility (SSRF), using a simulated energy-dispersive array detector consisting of a spatially scanning silicon-drift detector (SDD). Careful analysis and corrections are applied to account for various experimental hardware-related and diffraction angle-related factors. The resulting diffraction patterns show that the relative strength between different diffraction peaks from energy-dispersive XRD (EDXRD) spectra is consistent with that from angle-resolved XRD (ARXRD), which is necessary for analyzing crystal structures for unknown samples. The X-ray fluorescence (XRF) signal is collected simultaneously. XRF counts from all pixels are integrated directly by energy, while the diffraction spectra are integrated by d-spacing, resulting in a much improved peak strength and signal-to-noise (S/N) ratio for the array detector. In comparison with ARXRD, the diffraction signal generated by a white X-ray beam over monochromic light under the experimental conditions is about 104 times higher. The full width at half maximum (FWHM) of the peaks in q-space is found to be dependent on the energy resolution of the detector, the angle span of the detector, and the diffraction angle. It is possible for EDXRD to achieve the same or even smaller FWHM as ARXRD under the energy resolution of the current detector if the experimental parameters are properly chosen.
Keywords： High-throughput experiment White beam X-ray diffraction Energy-dispersive array detector Energy-dispersive X-ray diffraction Angle-resolved X-ray diffraction
Diffractive Deep Neural Networks at Visible Wavelengths Article
Hang Chen, Jianan Feng, Minwei Jiang, Yiqun Wang, Jie Lin, Jiubin Tan, Peng Jin
Engineering 2021, Volume 7, Issue 10, Pages 1485-1493 doi: 10.1016/j.eng.2020.07.032
Optical deep learning based on diffractive optical elements offers unique advantages for parallel processing, computational speed, and power efficiency. One landmark method is the diffractive deep neural network (D2NN) based on three-dimensional printing technology operated in the terahertz spectral range. Since the terahertz bandwidth involves limited interparticle coupling and material losses, this paper
extends D2NN to visible wavelengths. A general theory including a revised formula is proposed to solve any contradictions between wavelength, neuron size, and fabrication limitations. A novel visible light D2NN classifier is used to recognize unchanged targets (handwritten digits ranging from 0 to 9) and targets that have been changed (i.e., targets that have been covered or altered) at a visible wavelength of 632.8 nm. The obtained experimental classification accuracy (84%) and numerical classification accuracy (91.57%) quantify the match between the theoretical design and fabricated system performance. The presented framework can be used to apply a D2NN to various practical applications and design other new applications.
Keywords： Optical computation Optical neural networks Deep learning Optical machine learning Diffractive deep neural networks
Webb Space Telescope Hits Its Stride, Dazzling Astronomers
Mitch Leslie
Engineering 2023, Volume 22, Issue 3, Pages 3-6 doi: 10.1016/j.eng.2023.01.003
Super-resolution Near-field Optical Imaging and its Industrial Development
Wu Shifa
Strategic Study of CAE 2000, Volume 2, Issue 2, Pages 10-14
The super-resolution near-field optical imaging is an advanced project in the front of high engi-neering science and is an industry that should be developed early in the 21th century in China. In this paper, the historical events and PSTM developments in China are introduced. The imaging expressions of all kinds of the super-resolution near-field optical imaging systems are derived and compared with each others. In general, only with the mode of constant separation of tip-sample may obtain the pure optical image of sample, such as the image of refractive index, reflectivity or transmisivity of sample. The evanescent wave emitted from sample surface and the probe tip smaller than the diffraction limit are the two basic conditions of super-resolution in optical imaging. The other key to obtain the super-resolution is the modulated tip with vertical vibration in the mixture field of evanescent wave and propagating wave in near-field. For the transparent sample PSTM is the best to separate the pure optical image and topography of sampe. The author has applied for two invented patents on PSTM, which will be benificial to the development of PSTM industry in China.
Keywords： super-resolution near-field optics imaging surper resolution optical microscope
FAST: The Five-Hundred-Meter Aperture Spherical Radio Telescope
Peng Jiang, Hengqian Gan, Rui Yao, Jinghai Sun, Jiguang Lu, Dongjun Yu, Hui Li, Jinglong Yu, Bin Dong, Xiaoming Chai, Jianing Yin
Engineering 2023, Volume 28, Issue 9, Pages 21-25 doi: 10.1016/j.eng.2023.04.001
Fluorescence nanoscopy in neuroscience Review
Yangyundou Wang,Jian Lin,Qiming Zhang,Xi Chen,Haitao Luan,Min Gu
Engineering 2022, Volume 16, Issue 9, Pages 29-38 doi: 10.1016/j.eng.2020.11.010
Fluorescence nanoscopy provides imaging techniques that overcome the diffraction-limited resolution barrier in light microscopy, thereby opening up a new area of research in biomedical imaging in fields such as neuroscience. Here, we review the foremost fluorescence nanoscopy techniques, including descriptions of their applications in elucidating protein architectures and mobility, the real-time determination of synaptic parameters involved in neural processes, three-dimensional imaging, and the tracking of nanoscale neural activity. We conclude by discussing the prospects of fluorescence nanoscopy, with a particular focus on its deployment in combination with related techniques (e.g., machine learning) in neuroscience.
Keywords： Fluorescence imaging Diffraction limit Nanoscale resolution Neuroscience
Chinese space exploration and scientific motivation
Wu Ji
Strategic Study of CAE 2008, Volume 10, Issue 6, Pages 23-27
After a brief review of the exploration history of the human beings with emphasizing on the Chinese contributions, analysis is given on the motivation of the exploration activities. The scientific motivation is given particular attention. The general description and scientific objectives of four Chinese space exploration programs are given.
Keywords： China’s space exploration China-Russia joint Mars exploration project Kuafu project magnetosphere-ionishper-thermosphere exploration project solar polar orbit radio telescope
Development of High-Pressure Multigrain X-Ray Diffraction for Exploring the Earth’s Interior Review
Li Zhang, Hongsheng Yuan, Yue Meng, Ho-kwang Mao
Engineering 2019, Volume 5, Issue 3, Pages 441-447 doi: 10.1016/j.eng.2019.02.004
The lower mantle makes up more than a half of our planet’s volume. Mineralogical and petrological experiments on realistic bulk compositions under high pressure–temperature (P–T) conditions are essential for understanding deep mantle processes. Such high P–T experiments are commonly conducted in a laser-heated diamond anvil cell, producing a multiphase assemblage consisting of 100 nm to submicron crystallite grains. The structures of these lower mantle phases often cannot be preserved upon pressure quenching; thus, in situ characterization is needed. The X-ray diffraction (XRD) pattern of such a multiphase assemblage usually displays a mixture of diffraction spots and rings as a result of the coarse grain size relative to the small X-ray beam size (3–5 μm) available at the synchrotron facilities. Severe peak overlapping from multiple phases renders the powder XRD method inadequate for indexing new phases and minor phases. Consequently, structure determination of new phases in a high P–T multiphase assemblage has been extremely difficult using conventional XRD techniques. Our recent development of multigrain XRD in high-pressure research has enabled the indexation of hundreds of individual crystallite grains simultaneously through the determination of crystallographic orientations for these individual grains. Once indexation is achieved, each grain can be treated as a single crystal. The combined crystallographic information from individual grains can be used to determine the crystal structures of new phases and minor phases simultaneously in a multiphase system. With this new development, we have opened up a new area of crystallography under the high P–T conditions of the deep lower mantle. This paper explains key challenges in studying multiphase systems and demonstrates the unique capabilities of high-pressure multigrain XRD through successful examples of its applications.
Keywords： High pressure Synchrotron X-ray Multigrain Diamond anvil cell Minerals Petrology Earth’s interior
Engineering, Engineering System, Engineering System Theory, and System of Engineering Science
Wang Liancheng
Strategic Study of CAE 2001, Volume 3, Issue 6, Pages 15-18
Based on analysis of basic contents, nature and feature of engineering, this paper introduces concepts of engineering system and engineering system theory, then discusses objects of study and research methods of engineering system theory using thinking of general system theory. Finally, it expounds meta-discipline standing of engineering system theory in system of engineering science.
Keywords： engineering system system theory discipline
Qian Xuesen and System Engineering
Miao Dongsheng
Strategic Study of CAE 2002, Volume 4, Issue 3, Pages 16-20
This paper have looked back the formation of Qian Xuesen's system engineering idea, given a brief account of the main points of the system engineering theory with Chinese characteristics, and analysed how Qian went beyond system engineering.
Keywords： Qian Xuesen system idea system engineering system science
How to Deal with Revolutions in Train Control Systems
Hideo Nakamura
Engineering 2016, Volume 2, Issue 3, Pages 380-386 doi: 10.1016/J.ENG.2016.03.015
Train control systems ensure the safety of railways. This paper begins with a summary of the typical train control systems in Japan and Europe. Based on this summary, the author then raises the following question regarding current train control systems: What approach should be adopted in order to enhance the functionality, safety, and reliability of train control systems and assist in commercial operations on railways? Next, the author provides a desirable architecture that is likely to assist with the development of new train control systems based on current information and communication technologies. A new unified train control system (UTCS) is proposed that is effective in enhancing the robustness and competitiveness of a train control system. The ultimate architecture of the UTCS will be only composed of essential elements such as point machines and level crossing control devices in the field. Finally, a processing method of the UTCS is discussed.
Keywords： Train control system Railway signaling Communication-based train control system Automatic train protection and block system
Title Author Date Type Operation
Development of space-based diffractive telescopes
Wei Zhao, Xin Wang, Hua Liu, Zi-feng Lu, Zhen-wu Lu,wangxin971241@163.com,liuhua_rain@aliyun.com
Journal Article
Quantitative feedback controller design and test for an electro-hydraulic position control system in a large-scale reflecting telescope
Xiong-bin PENG, Guo-fang GONG, Hua-yong YANG, Hai-yang LOU, Wei-qiang WU, Tong LIU
Journal Article
Neutron Diffraction Investigation of the DyFe11Ti Magnetic Structure and Its Spin Reorientations
Olivier Isnard, Eder J. Kinast
Journal Article
High-Throughput Powder Diffraction Using White X-Ray Beam and a Simulated Energy-Dispersive Array Detector
Xiaoping Wang, Weiwei Dong, Peng Zhang, Haoqi Tang, Lanting Zhang, Tieying Yang, Peng Liu, Hong Wang, X.-D. Xiang
Journal Article
Diffractive Deep Neural Networks at Visible Wavelengths
Hang Chen, Jianan Feng, Minwei Jiang, Yiqun Wang, Jie Lin, Jiubin Tan, Peng Jin
Journal Article
FAST: The Five-Hundred-Meter Aperture Spherical Radio Telescope
Peng Jiang, Hengqian Gan, Rui Yao, Jinghai Sun, Jiguang Lu, Dongjun Yu, Hui Li, Jinglong Yu, Bin Dong, Xiaoming Chai, Jianing Yin
Journal Article
Fluorescence nanoscopy in neuroscience
Yangyundou Wang,Jian Lin,Qiming Zhang,Xi Chen,Haitao Luan,Min Gu
Journal Article
Development of High-Pressure Multigrain X-Ray Diffraction for Exploring the Earth’s Interior
Li Zhang, Hongsheng Yuan, Yue Meng, Ho-kwang Mao
Journal Article
Engineering, Engineering System, Engineering System Theory, and System of Engineering Science
Wang Liancheng
Journal Article
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