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优化光学亚像素定位精度极限——揭示小PSF的像素相位效应 Article
战海洋, 邢飞, 宝竞宇, 孙婷, 陈真真, 尤政, 袁利
《工程(英文)》 2023年 第27卷 第8期 页码 140-149 doi: 10.1016/j.eng.2023.03.009
Subpixel localization techniques for estimating the positions of point-like images captured by pixelated image sensors have been widely used in diverse optical measurement fields. With unavoidable imaging noise, there is a precision limit when estimating the target positions on image sensors, which depends on the detected photon count, noise, point spread function (PSF) radius, and PSF’s intra-pixel position. Previous studies have clearly reported the effects of the first three parameters on the precision limit but have neglected the intra-pixel position information. Here, we develop a localization precision limit analysis framework for revealing the effect of the intra-pixel position of small PSFs. To accurately estimate the precision limit in practical applications, we provide effective PSF (ePSF) modeling approaches and apply the Cramér-Rao lower bound. Based on the characteristics of small PSFs, we first derive simplified equations for finding the best precision limit and the best intra-pixel region for an arbitrary small PSF; we then verify these equations on real PSFs. Next, we use the typical Gaussian PSF to perform a further analysis and find that the final optimum of the precision limit is achieved at the pixel boundaries when the Gaussian radius is as small as possible, indicating that the optimum is ultimately limited by light diffraction. Finally, we apply the maximum likelihood method. Its combination with ePSF modeling allows us to successfully reach the precision limit in experiments, making the above theoretical analysis effective. This work provides a new perspective on combining image sensor position control with PSF engineering to make full use of information theory, thereby paving the way for thoroughly understanding and achieving the final optimum of the precision limit in optical localization.
关键词: Optical measurement Subpixel localization Precision limit optimization Small point spread functions Centroiding Star sensors
姚富强,张毅
《中国工程科学》 2011年 第13卷 第10期 页码 69-75
基于常规直扩体制的不足,笔者分析了跳码扩谱的必要性,提出和研究了一种新的预编码跳码扩谱通信抗干扰技术体制,重点讨论了预编码跳码扩谱的基本原理与自编码跳码扩谱的异同点、关键技术等,最后分析了其基本性能。该体制和性能已在实际中得到初步验证。
游宇航,李元洲,霍然
《中国工程科学》 2005年 第7卷 第7期 页码 86-89
运用网络模型(networks)对火灾在房间之间的蔓延过程进行了分析;计算不同条件下火灾沿不同路径蔓延的概率和时间,找出其中危险的因素;通过加强安全措施,对火灾蔓延过程进行了有效的控制。结果表明,应用网络模型来分析火灾在房间之间的蔓延过程,可对于蔓延的可能性和危险性作出了较好的预测。
《环境科学与工程前沿(英文)》 2021年 第15卷 第3期 doi: 10.1007/s11783-021-1386-6
• Aerosol transmission is an indispensable route of COVID-19 spread.
关键词: SARS-CoV-2 COVID-19 Environmental factor Aerosol transmission Epidemiologic characteristic
A ruptured recurrent small bowel gastrointestinal stromal tumour causing hemoperitoneum
null
《医学前沿(英文)》 2015年 第9卷 第1期 页码 108-111 doi: 10.1007/s11684-014-0344-0
Hemoperitoneum is a rare and potentially life-threatening complication of GIST. We reported a 54-year-old man who developed disseminated intra-abdominal recurrence from a previously resected gastrointestinal stromal tumour (GIST) of the small bowel, and the patient presented with hemoperitoneum. Emergent debulking surgery was performed. A high dose imatinib was prescribed. Despite the presence of residual disease, the patient was well clinically 8 months after the operation. Even though, there is no evidence to support the routine use of debulking surgery in the management of GIST. In our patient, disease progression after second line targeted therapy and the absence of alternative treatment options for spontaneous rupture and hemoperitoneum prompted us to treat the patient aggressively. Resection of the ruptured GIST was carried out for control of bleeding and to prevent recurrent bleeding in this patient with good surgical risks. During the treatment decision-making, the patient’s general condition, the risk of surgery and the extent of dissemination were taken into consideration. In this patient who presented with spontaneous rupture of a small intestinal GIST, the novel use of targeted therapy and aggressive surgical treatment produced reasonably good survival outcome.
关键词: gastrointestinal stromal tumour hemoperitoneum small bowel GIST small bowel neoplasm imatinib
朱凼凼,冯咬齐,向树红
《中国工程科学》 2005年 第7卷 第8期 页码 89-94
概述了国内外动力学模型修正技术的研究状况,研究了近些年发展起来的基于频响函数的动力学模型修正方法;利用航天器振动试验测量所得的频响函数,从理论上介绍了频响函数残差法、设计参数型频响函数法和摄动型频响函数法三种基于频响函数的动力学模型修正方法,为动力学模型修正技术的发展提供参考。
《化学科学与工程前沿(英文)》 2023年 第17卷 第12期 页码 2144-2155 doi: 10.1007/s11705-023-2362-4
关键词: copper sulfide nanoparticles chemodynamic therapy photothermal therapy carbon dots silica nanoparticles
张锡祥
《中国工程科学》 2000年 第2卷 第7期 页码 55-65
文章介绍了从地对空干扰机的发展概况,从单一干扰轰炸瞄准雷达,发展成地对空干扰系统和系列,可以干扰空载作战飞机雷达、导弹制导雷达、精密制导雷达、预警机雷达、星载探测雷达等,分析了这些雷达的干扰原理、干扰方法和干扰机的布局。文章对新体制雷达的干扰压制系数进行了分析,导出各类新体制雷达的干扰压制系数表达式,并提供了计算机仿真和实际试验的结果。文章分析了90年代以来两次现代化局部战争,地对空干扰系统若能发挥作用,将使被入侵国家的损失率下降,使入侵者的损失率升高。地对空干扰系统具有攻防兼备的立体干扰系列功能,需要经费较低,很适合于第三世界国家的需求,具有广泛的发展前景。
Simulation and experimental improvement on a small-scale Stirling thermo-acoustic engine
Mao CHEN,Yonglin JU
《能源前沿(英文)》 2016年 第10卷 第1期 页码 37-45 doi: 10.1007/s11708-015-0390-6
关键词: thermo-acoustic Stirling engine small-scale simulation experiment
Discovery of small molecule degraders for modulating cell cycle
《医学前沿(英文)》 页码 823-854 doi: 10.1007/s11684-023-1027-5
Fine-tuning cell organelle dynamics during mitosis by small GTPases
《医学前沿(英文)》 2022年 第16卷 第3期 页码 339-357 doi: 10.1007/s11684-022-0926-1
Gut microbiota and its implications in small bowel transplantation
null
《医学前沿(英文)》 2018年 第12卷 第3期 页码 239-248 doi: 10.1007/s11684-018-0617-0
The gut microbiota is mainly composed of a diverse population of commensal bacterial species and plays a pivotal role in the maintenance of intestinal homeostasis, immune modulation and metabolism. The influence of the gut microbiota on solid organ transplantation has recently been recognized. In fact, several studies indicated that acute and chronic allograft rejection in small bowel transplantation (SBT) is closely associated with the alterations in microbial patterns in the gut. In this review, we focused on the recent findings regarding alterations in the microbiota following SBT and the potential roles of these alterations in the development of acute and chronic allograft rejection. We also reviewed important advances with respect to the interplays between the microbiota and host immune systems in SBT. Furthermore, we explored the potential of the gut microbiota as a microbial marker and/or therapeutic target for the predication and intervention of allograft rejection and chronic dysfunction. Given that current research on the gut microbiota has become increasingly sophisticated and comprehensive, large cohort studies employing metagenomic analysis and multivariate linkage should be designed for the characterization of host–microbe interaction and causality between microbiota alterations and clinical outcomes in SBT. The findings are expected to provide valuable insights into the role of gut microbiota in the development of allograft rejection and other transplant-related complications and introduce novel therapeutic targets and treatment approaches in clinical practice.
关键词: gut microbiota small bowel transplantation acute rejection chronic rejection mucosal immunity biomarker microbiota-targeted therapy
null
《医学前沿(英文)》 2013年 第7卷 第2期 页码 157-171 doi: 10.1007/s11684-013-0272-4
Non-small-cell lung cancer (NSCLC) is the most common cause of premature death among the malignant diseases worldwide. The current staging criteria do not fully capture the complexity of this disease. Molecular biology techniques, particularly gene expression microarrays, proteomics, and next-generation sequencing, have recently been developed to facilitate effectively its molecular classification. The underlying etiology, pathogenesis, therapeutics, and prognosis of NSCLC based on an improved molecular classification scheme may promote individualized treatment and improve clinical outcomes. This review focuses on the molecular classification of NSCLC based on gene expression microarray technology reported during the past decade, as well as their applications for improving the diagnosis, staging and treatment of NSCLC, including the discovery of prognostic markers or potential therapeutic targets. We highlight some of the recent studies that may refine the identification of NSCLC subtypes using novel techniques such as epigenetics, proteomics, or deep sequencing.
关键词: non-small-cell lung cancer molecular typing individualized medicine molecular-targeted therapy gene expression profiling
Potential functions of esophageal cancer-related gene-4 in the cardiovascular system
Rui Zhou, Yuanshu Liu, Wenjun Huang, Xitong Dang
《医学前沿(英文)》 2019年 第13卷 第6期 页码 639-645 doi: 10.1007/s11684-019-0701-0
关键词: tumor suppressor gene esophageal cancer-related gene-4 cardiovascular disease hypoxia
Performance prediction of switched reluctance generator with time average and small signal models
Jyoti KOUJALAGI, B. UMAMAHESWARI, R. ARUMUGAM
《能源前沿(英文)》 2013年 第7卷 第1期 页码 56-68 doi: 10.1007/s11708-012-0216-8
关键词: generator reluctance switching model small signal model time average model
标题 作者 时间 类型 操作
Aerosol transmission, an indispensable route of COVID-19 spread: case study of a department-store cluster
期刊论文
Silica-based nanoarchitecture for an optimal combination of photothermal and chemodynamic therapy functions
期刊论文
Simulation and experimental improvement on a small-scale Stirling thermo-acoustic engine
Mao CHEN,Yonglin JU
期刊论文
Molecular classification of non-small-cell lung cancer: diagnosis, individualized treatment, and prognosis
null
期刊论文
Potential functions of esophageal cancer-related gene-4 in the cardiovascular system
Rui Zhou, Yuanshu Liu, Wenjun Huang, Xitong Dang
期刊论文