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多孔径光学成像系统及其光场采集数学模型 Review Article

祁启明,傅瑞罡,邵铮铮,王平,范红旗

《信息与电子工程前沿(英文)》 2022年 第23卷 第6期   页码 823-844 doi: 10.1631/FITEE.2100058

摘要:

受昆虫复眼启发,为提高光学成像质量,如获得高分辨率图像或大视场图像,研究者提出了许多多孔径光学成像系统。光场采集数学模型是联系多孔径光学成像系统结构设计与应用的纽带,但光场采集数学模型较少被关注。本文系统梳理了典型多孔径光学成像系统(仿生复眼、光场相机、相机阵列),总结了不同结构下多孔径光学成像系统的一般性光场采集数学模型。列出的数学模型既可用于计算特定多孔径光学成像系统的关键指标,如视场大小和子图像重叠比等,也可作为数学工具,便于研究者完成对成像系统的定量设计与评估。

关键词: 多孔径光学成像系统;仿生复眼;光场相机;相机阵列;光场采集模型    

Development of real-time onion disease monitoring system using image acquisition

Du-Han KIM, Kyeong-Hwan LEE, Chang-Hyun CHOI, Tae-Hyun CHOI, Yong-Joo KIM

《农业科学与工程前沿(英文)》 2018年 第5卷 第4期   页码 469-474 doi: 10.15302/J-FASE-2018213

摘要:

In this study, real-time disease monitoring was conducted on onion which is the most representative crop in Republic of Korea, using an image acquisition system newly developed for the mobile measurement of phenotype. The purpose of this study was to improve the accuracy of prediction of disease and state variables by processing images acquired from monitoring. The image acquisition system was consisted of two parts, a motorized driving system and a PTZ (pan, tilt and zoom) camera to take images of the plants. The acquired images were processed as follows. Noise was removed through an image filter and RGB (red, green and blue) colors were converted to HSV (hue, saturation and value), which enabled thresholding of areas with different colors and properties for image binarization by comparing the color of onion leaf with ambient areas. Four objects with the most significant browning in the onion leaf to the naked eye were selected as the samples for data acquired. The thresholding method with image processing was found to be superior to the naked eye in identifying accurate disease areas. In addition, it was found that the incidence of disease was different in each disease area ratio. As a result, the use of image acquisition system in image processing analysis will enable more prompt detection of any changes in the onion and monitoring of disease outbreaks during the crop lifecycle.

关键词: imaging acquisition system     disease     downy mildew     onion    

A Miniature Meta-Optical System for Reconfigurable Wide-Angle Imaging and Polarization-Spectral Detection

Fei Zhang,Minghao Liao,Mingbo Pu,Yinghui Guo,Lianwei Chen,Xiong Li,Qiong He,Tongtong Kang,Xiaoliang Ma,Yuan Ke,Xiangang Luo,

《工程(英文)》 doi: 10.1016/j.eng.2023.07.008

摘要: Wide-angle imaging and spectral detection play vital roles in tasks such as target tracking, object classification, and anti-camouflage. However, limited by their intrinsically different architectures, as determined by frequency dispersion requirements, their simultaneous implementation in a shared-aperture system is difficult. Here, we propose a novel concept to realize reconfigurable dual-mode detection based on electrical-control tunable metasurfaces. As a proof-of-concept demonstration, the simultaneous implementation of wide-angle imaging and polarization-spectral detection in a miniature shared-aperture meta-optical system is realized for the first time via the electrical control of cascaded catenary-like metasurfaces. The proposed system supports the imaging (spectral) resolution of approximately 27.8 line-pairs per millimeter (lp·mm−1; ∼80 nm) for an imaging (spectral) mode from 8 to 14 μm. This system also bears a large field of view of about 70°, enabling multi-target recognition in both modes. This work may promote the miniaturization of multifunctional optical systems, including spectrometers and polarization imagers, and illustrates the potential industrial applications of meta-optics in biomedicine, security, space exploration, and more.

关键词: Metasurfaces     Reconfigurable     Imaging     Spectral    

Analysis and control of micro-stepping characteristics of ultrasonic motor

Ning CHEN, Jieji ZHENG, Xianliang JIANG, Shixun FAN, Dapeng FAN

《机械工程前沿(英文)》 2020年 第15卷 第4期   页码 585-599 doi: 10.1007/s11465-019-0577-3

摘要: Micro-stepping motion of ultrasonic motors satisfies biomedical applications, such as cell operation and nuclear magnetic resonance, which require a precise compact-structure non-magnetization positioning device. When the pulse number is relatively small, the stopping characteristics have a non-negligible effect on the entire stepwise process. However, few studies have been conducted to show the rule of the open-loop stepwise motion, especially the shutdown stage. In this study, the modal differences of the shutdown stage are found connected with amplitude and velocity at the turn-off instant. Changes of the length in the contact area and driving zone as well as the input currents, vibration states, output torque, and axial pressure are derived by a simulation model to further explore the rules. The speed curves and vibration results in functions of different pulse numbers are compared, and the stepwise motion can be described by a two-stage two-order transfer function. A test workbench based on the Field Programmable Gate Array is built for acquiring the speed, currents, and feedback voltages of the startup–shutdown stage accurately with the help of its excellent synchronization performances. Therefore, stator vibration, rotor velocity, and terminal displacements under different pulse numbers can be compared. Moreover, the two-stage two-order model is identified on the stepwise speed curves, and the fitness over 85% between the simulation and test verifies the model availability. Finally, with the optimization of the pulse number, the motor achieves 3.3 µrad in clockwise and counterclockwise direction.

关键词: ultrasonic motor     stepping characteristics     pulse number control     synchronous acquisition system     precise positioning    

风险矩阵法在武器装备采办风险评估中的运用

李忠民,魏一鸣,汤淑春,陈健

《中国工程科学》 2006年 第8卷 第6期   页码 95-99

摘要:

在对国外广泛采用的风险矩阵评估方法进行全面分析和系统总结的基础上,对风险矩阵方法在我国武器装备采办风险评估中的运用进行了探讨,并从风险影响和风险概率两个准则入手,以某武器型号采办为例示范性地进行了风险评估,从而为制定科学合理的武器装备采办风险管理提供决策依据。

关键词: 风险矩阵方法     风险评估     武器装备采办    

evaluation of renal function using diffusion weighted imaging and diffusion tensor imaging in type 2

null

《医学前沿(英文)》 2014年 第8卷 第4期   页码 471-476 doi: 10.1007/s11684-014-0365-8

摘要:

This work aims to estimate the value of diffusion weighted imaging (DWI) and diffusion tensor imaging (DTI) in detecting early-stage kidney injury in type 2 diabetic patients with normoalbuminuria (NAU) versus microalbuminuria (MAU) prospectively. A total of 30 T2DM patients with normal kidney function were recruited and assigned to the NAU group (n = 14) or MAU group (n= 16) according to 8 h overnight urinary albuminuria excretion rate (AER) results. A contemporary cohort of health check-up recipients were included as controls (n = 12). DWI and DTI scans were performed on bilateral kidney using SE single-shot EPI, and apparent diffusion coefficient (ADC) and fractional anisotropy (FA) of the renal parenchyma was determined from ADC and FA maps of the three groups. ADC and FA values were compared among the three groups. According to DWI with a b value of 400 s/mm2, the MAU and NAU groups showed significantly lowered mean ADC values compared with the healthy controls (P<0.01). The mean ADC in the MAU group [(2.22±0.07)×10–3 mm2/s] was slightly lower than that of the NAU group [(2.31±0.22)×10–3 mm2/s], but this difference was not statistically significant (P>0.05). The FA value in the MAU group was higher than that in the control group (0.45±0.07 vs. 0.39±0.03, = 0.004) but did not differ from that in the NAU group (0.42±0.03) (P>0.05). ADC and FA values may be more sensitive than urine AER in reflecting early-stage kidney injury and, hence, may facilitate earlier detection and quantitative evaluation of kidney injury in T2DM patients. Combined evaluation of ADC and FA values may provide a better quantitative approach for identifying diabetic nephropathy at early disease stages.

关键词: type 2 diabetes mellitus     microalbuminuria     diffusion weighted imaging     diffusion tensor imaging     early-stage kidney injury    

Quality control based on electrode displacement and force in resistance spot welding

Chuntao JI, Lipeng DENG

《机械工程前沿(英文)》 2010年 第5卷 第4期   页码 412-417 doi: 10.1007/s11465-010-0114-x

摘要: The behaviors of electrode displacement and force during spot welding under various conditions, such as different weld currents, electrode forces, and welding times, were studied. Tests were conducted on a 170?kVA MFDC spot welder. Data were collected via a multichannel high-speed data acquisition system and were analyzed with MATLAB. Behaviors of 5182 aluminum and mild steel in spot welding were compared. Results show that nugget expansion rate does not reach zero for aluminium as it does for mild steel as nugget grew to a certain size. A linear relationship is found between the nugget size and maximum expansion that facilitates online weld quality evaluation. An electrode force peak is observed and believed relevant to the sufficient nugget size.

关键词: aluminum     electrode displacement     electrode force     nugget size     data acquisition    

Carbon dots-based fluorescence sensor for two-photon imaging of pH in diabetic mice

《化学科学与工程前沿(英文)》 2023年 第17卷 第3期   页码 298-306 doi: 10.1007/s11705-022-2212-9

摘要: Herein, a reversible pH fluorescent sensor was developed using caffeic acid as the precursor by one-step solvothermal synthesis method. The carbon dots-based sensor (CA-CDs) exhibited pH-dependent increase in fluorescence intensity and showed linear relationship in the range of pH 6.60 and 8.00. Notably, the fluorescence sensor has a reversible response to pH change. Finally, the CA-CDs has been successfully applied for two-photon imaging of the pH in liver and kidney of diabetic mice. Imaging results showed that the pH value in kidney of diabetic mice was lower than that of the normal mice, while the pH value in liver of diabetic mice was almost the same as that of the normal mice. The present study provides a simple analytical method for pH detection suitable for in vivo.

关键词: carbon dots     two-photon imaging     pH     diabetic mice    

In vivo imaging of hematopoietic stem cell development in the zebrafish

Panpan Zhang, Feng Liu

《医学前沿(英文)》 2011年 第5卷 第3期   页码 239-247 doi: 10.1007/s11684-011-0123-0

摘要: imaging is crucial for developmental biology and can further help to follow cell development/differentiation in normal and pathological conditions. Recent advances in optical imaging techniques has facilitated tracing of the developmental dynamics of a specific organ, tissue, or even a single cell. The zebrafish is an excellent model for imaging of hematopoiesis due to its transparent embryo at early stage; moreover, different zebrafish hematopoietic stem cells (HSCs) transgenic lines have been demonstrated as very useful tools for illustrating the details of the HSC developmental process. In this review, we summarize recent studies related to the non-invasive imaging of HSC transgenics, to show that zebrafish transgenic lines are powerful tools for developmental biology and disease. At the end of the review, the perspective and some open questions in this field will be discussed.

关键词: hematopoietic stem cell     hematopoiesis     in vivo imaging     transgenics     zebrafish    

西堠门大桥结构监测系统的设计与实现(II):系统实现

刘志强,李娜,郭健 ,冯良平,宋刚

《中国工程科学》 2010年 第12卷 第7期   页码 101-106

摘要:

采用“西堠门大桥结构监测系统的设计与实现(I):系统设计”中的设计方法,为西堠门大桥设计并实现桥梁结构监测系统。研究西堠门大桥结构监测系统的总体设计方案、子系统的设计方案及其软硬件的实现。分析西堠门大桥结构监测系统在运营中监测的桥梁荷载和结构响应。研究结果表明,西堠门大桥结构监测系统正常运行,实现了预期设计功能,基于工业以太网分布式数据采集与传输系统在桥梁结构监测系统中得以成功应用,可在其他工程中加以推广。

关键词: 桥梁     结构监测系统     工业以太网     分布式数据采集系统     系统集成    

Anefficient quadrature demodulator for medical ultrasound imaging

Hao ZHOU,Yin-fei ZHENG

《信息与电子工程前沿(英文)》 2015年 第16卷 第4期   页码 301-310 doi: 10.1631/FITEE.1400205

摘要: Quadrature demodulation is used in medical ultrasound imaging to derive the envelope and instantaneous phase of the received radio-frequency (RF) signal. In quadrature demodulation, RF signal is multiplied with the sine and cosine wave reference signal and then low-pass filtered to produce the base-band complex signal, which has high computational complexity. In this paper, we propose an efficient quadrature demodulation method for B-mode and color flow imaging, in which the RF signal is demodulated by a pair of finite impulse response filters without mixing with the reference signal, to reduce the computational complexity. The proposed method was evaluated with simulation and in vivo experiments. From the simulation results, the proposed quadrature demodulation method produced similar normalized residual sum of squares (NRSS) and velocity profile compared with the conventional quadrature demodulation method. In the in vivo color flow imaging experiments, the time of the demodulation process was 5.66 ms and 3.36 ms, for the conventional method and the proposed method, respectively. These results indicated that the proposed method can maintain the performance of quadrature demodulation while reducing computational complexity.

关键词: B-mode ultrasound imaging     Color flow imaging     Quadrature demodulation     Finite impulse response filter    

光场成像技术:模型、标定、重建及应用 Review

Hao ZHU, Qing WANG, Jingyi YU

《信息与电子工程前沿(英文)》 2017年 第18卷 第9期   页码 1236-1249 doi: 10.1631/FITEE.1601727

摘要: 光场成像是计算摄像学领域一项新兴技术。基于对成像模型和光路的创新设计,光场相机不仅记录了三维物体的空间强度,而且捕获了物理世界中的角度信息。这为解决三维重建、显著区域检测、目标识别等计算机视觉问题提供了新途径。本文首先回顾了光场相机的三个关键问题,包括成像模型、标定理论以及重建方法。然后,系统介绍了光场成像技术在信息学、物理学、医学和生物学等领域的应用现状。最后,讨论了光场成像目前存在的问题,并展望了光场成像技术的应用前景。

关键词: 光场成像;全光函数;成像模型;标定;重建    

Simultaneous acquisition of CT angiography and whole brain CT perfusion images by using multiphase dynamic

Weiwei CHEN, Jianpin QI, Wenzhen ZHU, Wenhua HUANG, Jinmei SONG

《医学前沿(英文)》 2009年 第3卷 第2期   页码 230-235 doi: 10.1007/s11684-009-0023-8

摘要: We implemented a new protocol — multiphase dynamic helical scan to acquire CT angiography (CTA) and whole brain CT perfusion (CTP) images simultaneously with single scan on 16 multidetector CT (MDCT). A total of 90 patients who were randomly assigned into 3 groups were included in our study. Each group underwent CT scan by using the new protocol, traditional CTA and CTP protocol, respectively. The image quality of CTA, the CTP parameter values and the X-ray doses were measured and compared between the new protocol and the traditional protocols. There was no statistically significant difference in the CTA image quality between the above methods ( =0.55). For CTP parameters, the new protocol tended to overestimate the blood volume (BV) and blood flow (BF) value, and to underestimate the mean transit time (MTT) value compared with the traditional method. However, there was no statistically significant difference in BV, BF, and MTT value between the two methods except permeability surface (PS) ( >0.05). The volume CT dose index (CTDIvol) and dose length product (DLP) of our protocol were lower than the traditional one. The new protocol can obtain valuable diagnostic information in a shorter time without significant compromise in image quality. In addition, it reduces the radiation dose as well as contrast medium usage on the patient.

关键词: computed tomography angiography     computed tomography perfusion    

Synthesis and application of superparamagnetic iron oxide nanoparticles in targeted therapy and imaging

Liangqian Tong, Ming Zhao, Shu Zhu, Jing Chen

《医学前沿(英文)》 2011年 第5卷 第4期   页码 379-387 doi: 10.1007/s11684-011-0162-6

摘要: Superparamagnetic iron oxide (SPIO) nanoparticles have become a popular strategy of cancer treatment and molecular imaging because of their versatile properties and biocompatibility. A variety of studies have shown the exciting potential of functionalized SPIO nanoparticles, such as surface-coated, targeted ligand-conjugated, and/or drug-loaded SPIO nanoparticles, as powerful tools for targeted imaging and therapy. Moreover, the applications of SPIO nanoparticles that integrate diagnosis and therapy in SPIO nanoparticles facilitate the monitoring of therapeutic efficacy during treatment. In the present review, we primarily concentrate on the recent advancements in the field of SPIO nanoparticles in terms of synthesis, targeted therapy, and cancer imaging.

关键词: nanoparticles     superparamagnetic iron oxide     targeted therapy     molecular imaging     cancer    

A highly selective fluorescent probe for real-time imaging of UDP-glucuronosyltransferase 1A8 in living

《化学科学与工程前沿(英文)》 2022年 第16卷 第1期   页码 103-111 doi: 10.1007/s11705-021-2064-8

摘要: Uridine diphosphate (UDP)-glucuronosyltransferases (UGTs) are enzymes involved in the biotransformation of important endogenous compounds such as steroids, bile acids, and hormones as well as exogenous substances including drugs, environmental toxicants, and carcinogens. Here, a novel fluorescent probe BDMP was developed based on boron-dipyrromethene (BODIPY) with high sensitivity for the detection of UGT1A8. The glucuronidation of BDMP not only exhibited a red-emission wavelength (λex/λem = 500/580 nm), but also displayed an excellent UGT1A8-dependent fluorescence signal with a good linear relationship with UGT1A8 concentration. Based on this perfect biocompatibility and cell permeability, BDMP was successfully used to image endogenous UGT1A8 in human cancer cell lines (LoVo and HCT15) in real time. In addition, BDMP could also be used to visualize UGT1A8 in tumor tissues. These results suggested that BDMP is a promising molecular tool for the investigation of UGT1A8-mediated physiological function in humans.

关键词: UDP-glucuronosyltransferase 1A8     fluorescent probe     subtype selectivity     fluorescence imaging    

标题 作者 时间 类型 操作

多孔径光学成像系统及其光场采集数学模型

祁启明,傅瑞罡,邵铮铮,王平,范红旗

期刊论文

Development of real-time onion disease monitoring system using image acquisition

Du-Han KIM, Kyeong-Hwan LEE, Chang-Hyun CHOI, Tae-Hyun CHOI, Yong-Joo KIM

期刊论文

A Miniature Meta-Optical System for Reconfigurable Wide-Angle Imaging and Polarization-Spectral Detection

Fei Zhang,Minghao Liao,Mingbo Pu,Yinghui Guo,Lianwei Chen,Xiong Li,Qiong He,Tongtong Kang,Xiaoliang Ma,Yuan Ke,Xiangang Luo,

期刊论文

Analysis and control of micro-stepping characteristics of ultrasonic motor

Ning CHEN, Jieji ZHENG, Xianliang JIANG, Shixun FAN, Dapeng FAN

期刊论文

风险矩阵法在武器装备采办风险评估中的运用

李忠民,魏一鸣,汤淑春,陈健

期刊论文

evaluation of renal function using diffusion weighted imaging and diffusion tensor imaging in type 2

null

期刊论文

Quality control based on electrode displacement and force in resistance spot welding

Chuntao JI, Lipeng DENG

期刊论文

Carbon dots-based fluorescence sensor for two-photon imaging of pH in diabetic mice

期刊论文

In vivo imaging of hematopoietic stem cell development in the zebrafish

Panpan Zhang, Feng Liu

期刊论文

西堠门大桥结构监测系统的设计与实现(II):系统实现

刘志强,李娜,郭健 ,冯良平,宋刚

期刊论文

Anefficient quadrature demodulator for medical ultrasound imaging

Hao ZHOU,Yin-fei ZHENG

期刊论文

光场成像技术:模型、标定、重建及应用

Hao ZHU, Qing WANG, Jingyi YU

期刊论文

Simultaneous acquisition of CT angiography and whole brain CT perfusion images by using multiphase dynamic

Weiwei CHEN, Jianpin QI, Wenzhen ZHU, Wenhua HUANG, Jinmei SONG

期刊论文

Synthesis and application of superparamagnetic iron oxide nanoparticles in targeted therapy and imaging

Liangqian Tong, Ming Zhao, Shu Zhu, Jing Chen

期刊论文

A highly selective fluorescent probe for real-time imaging of UDP-glucuronosyltransferase 1A8 in living

期刊论文