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Search Results: 1 - 10 of 127099 matches for " Linbo Li "
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Study of Supper Resolution Processing Methods for Thick Pinhole Image  [PDF]
Hongwei Xie, Faqiang Zhang, Jianhua Zhang, Zeping Xu, Linbo Li
Journal of Signal and Information Processing (JSIP) , 2013, DOI: 10.4236/jsip.2013.42030
Abstract:

An image super resolution reconstruction method was used to improve the spatial resolution of the thick pinhole imaging system and to mitigate the limitations of the image spatial resolution of the hardware of the image diagnostic system. The thick pinhole is usually applied into the diagnostics of the high energy neutron radiation image. Due to the impacts among its energy flux, spatial resolution and effective field of view, in dealing with the large area radiation source, the spatial resolution of the thick pinhole neutron image cannot meet the requirements for high precision modeling of the radiation source image. In this paper, the Lucy-Richardson image super resolution reconstruction method was used to simulate the thick pinhole imaging and super resolution image reconstruction. And the spatial resolution of the image could be increased by over three times after the image super resolution reconstruction. Besides, in dealing with the pseudo-noise, plum blossom shape appeared in the image super resolution reconstruction. The analysis of the source of the pseudo-noise was made based on the simulation of the image reconstruction under various conditions according to the characteristics of the thick pinhole image configuration.

Performance Evaluation of the Thick Pinhole Gamma Rays Diagnostic System*  [PDF]
Hongwei Xie, Jinchuan Chen, Linbo Li, Qiang Yi
Journal of Analytical Sciences, Methods and Instrumentation (JASMI) , 2018, DOI: 10.4236/jasmi.2018.83003
Abstract: The diagnostic methods for the profile of the radiation source were estab-lished at first based on the pinhole imaging principle. In this paper, the relationships among various parameters of the gamma-rays crammer such as the modulation transfer function (MTF), the noise power spectrum (NPS), the signal-noise ratio (SNR) and the detective quantum efficiency (DQE) are developed and studied experimentally on the cobalt radiation source. The image diagnostic system is consisting with rays-fluorescence convertor (YAG crystal), optical imaging system, MCP image intensifier, CCD camera and other devices. The spatial resolution of the modulation transfer function (MTF) at 10% intensity was measured as 1 lp/mm by knife-edge method. The quantum of the measurement system is about 150 under weak radiation condition due to the single particle detection efficiency of the system. The dynamic range was inferred preliminarily as about 437. The required radiation intensity was calculated using the experiment result for the (SNR) = 1, 5, 10, respectively. The theoretical investigation results show that the radiation image with (SNR) = 1 can be only obtained when the pinhole diameter is 0.7 mm, object distance and image distance are both 200 cm, and the radiation intensity is about 1.0 × 1012 Sr-1·cm-2.
Evaluation of Major Factors Affecting Spatial Resolution of Gamma-Rays Camera  [PDF]
Hongwei Xie, Jianhua Zhang, Jinchuan Chen, Faqiang Zhang, Linbo Li, Jianming Qi, Yanyun Chu
Journal of Analytical Sciences, Methods and Instrumentation (JASMI) , 2013, DOI: 10.4236/jasmi.2013.34029
Abstract:

The spatial resolution of the gamma-rays camera was measured on a60Co gamma-rays source with edge method. The gamma-rays camera is consisting with rays-fluorescence convertor, optical imaging system, MCP image intensifier, CCD camera, electronic control system and other devices, and is mainly used in the image diagnostics of the intense pulse radiation sources [1]. Due to the relatively big quantum detective efficiency (DQE) and quantum gain of the gamma-rays, etc., the experimental data were processed by averaging multiple images and fitting curves. According to the experimental results, the spatial resolution MTF (modulation transfer function) at the 10% intensity was about 2lp/mm. Meanwhile, because of the relatively big dispersion effects of the fluorescence transmissions in the scintillator and the optical imaging system, the maximal single-noise ratio (SNR) of the camera was found to be about 5:1. In addition, the spatial resolution of the camera was measured with pulse X-rays with 0.3MeV in average energy and exclusion of the effects of secondary electrons from consideration. Accordingly, the spatial resolution MTF at the 10% intensity was about 5lp/mm. This could be an additional evidence to verify the effects of secondary electrons induced by the 1.25MeV gamma-rays in the scintillator upon the spatial resolution. Based on our analysis, the dispersion sizes of the secondary electrons in the scintillator are about 0.4mm-0.6mm. Comparatively, as indicated by the detailed analysis of the spatial resolutions of the MCP image intensifier and CCD devices, both of them have little effect on the spatial resolution of the gamma-rays camera that could be well neglected.

A Structured Construction of Optimal Measurement Matrix for Noiseless Compressed Sensing via Analog Polarization
Linbo Li,Hessam Mahdavifar,Inyup Kang
Mathematics , 2012,
Abstract: In this paper, we propose a method of structured construction of the optimal measurement matrix for noiseless compressed sensing (CS), which achieves the minimum number of measurements which only needs to be as large as the sparsity of the signal itself to be recovered to guarantee almost error-free recovery, for sufficiently large dimension. To arrive at the results, we employ a duality between noiseless CS and analog coding across sparse additive noisy channel (SANC). Extending Renyi Information Dimension to Mutual Information Dimension (MID), we show the operational meaning of MID to be the fundamental limit of asymptotically error-free analog transmission across SANC under linear analog encoding constraint. We prove that MID polarizes after analog polar transformation and obeys the same recursive relationship as BEC. We further prove that analog polar encoding can achieve the fundamental limit of achievable dimension rate with vanishing Pe across SANC. From the duality, a structured construction scheme is proposed for the linear measurement matrix which achieves the minimum measurement requirement for noiseless CS.
MASKING OF SYMMETRICAL PHASE FUNCTION
对称相位函数掩模化的研究

Bai Linbo,Du Chunlei,Li Zhan,
白临波
,杜春雷,李展

光子学报 , 2000,
Abstract: 本文对各种连续对称相位函数及其特性进行了分析,讨论了相位函数的2π调制、2^N和N-1法量化等问题及数据处理过程,提出二元衍射元件CIF(Caltech Intermediate Form)格式掩模数据的生成方法,并建立了实用软件,为激光直写技术实现二元衍射光学元件制作提供了有效的手段。
Fast Tensor Principal Component Analysis via Proximal Alternating Direction Method with Vectorized Technique  [PDF]
Haiyan Fan, Gangyao Kuang, Linbo Qiao
Applied Mathematics (AM) , 2017, DOI: 10.4236/am.2017.81007
Abstract: This paper studies the problem of tensor principal component analysis (PCA). Usually the tensor PCA is viewed as a low-rank matrix completion problem via matrix factorization technique, and nuclear norm is used as a convex approximation of the rank operator under mild condition. However, most nuclear norm minimization approaches are based on SVD operations. Given a matrix \"\" , the time complexity of SVD operation is O(mn2), which brings prohibitive computational complexity in large-scale problems. In this paper, an efficient and scalable algorithm for tensor principal component analysis is proposed which is called Linearized Alternating Direction Method with Vectorized technique for Tensor Principal Component Analysis (LADMVTPCA). Different from traditional matrix factorization methods, LADMVTPCA utilizes the vectorized technique to formulate the tensor as an outer product of vectors, which greatly improves the computational efficacy compared to matrix factorization method. In the experiment part, synthetic tensor data with different orders are used to empirically evaluate the proposed algorithm LADMVTPCA. Results have shown that LADMVTPCA outperforms matrix factorization based method.
Evaluation on the Financial Competitiveness of Chinese Listed Real Estate Companies Based on Entropy Method
Wei Lin,Linbo Shao
Quantitative Finance , 2013,
Abstract: The real estate is a pillar industry of China's national economy. Due to changes in policy and market conditions, the real estate companies are facing greater pressures to survive in a competitive environment. They must improve their financial competitiveness. Based on the conceptual framework of financial competitiveness, this paper presented a financial competitiveness evaluation index system, covering four aspects, including profitability, solvency, sustainable development and operational capacity. Entropy value method is applied to determine the index weight. 105 listed real estate company's financial competitiveness are evaluated, the results show that: high-scoring company has strong profitability, sustainable development and operational capacity; low-scoring company has weak profitability and poor ability of sustainable development; solvency doesn't affect the company's financial competitiveness obviously.
Interactions of miR-34b/c and TP53 Polymorphisms on the Risk of Intracranial Aneurysm
Lijuan Li,Xiutian Sima,Peng Bai,Lushun Zhang,Hong Sun,Weibo Liang,Jianxing Liu,Lin Zhang,Linbo Gao
Clinical and Developmental Immunology , 2012, DOI: 10.1155/2012/567586
Abstract: Several lines of evidence indicate that inflammatory processes play a key role in the happening and development of intracranial aneurysm (IA). Recently, polymorphisms in the TP53 gene were shown to be associated with inflammation and inflammatory disease. The aim of this study was to investigate the interactions of miR-34b/c and TP53 Arg72-Pro polymorphisms on the risk of IA in a Chinese population. A total of 590 individuals (including 164 patients with IA and 426 controls) were involved in this study. The polymorphisms (i.e., miR-34b/c rs4938723 and TP53 Arg72-Pro) were genotyped by polymerase chain reaction-restriction fragment length polymorphism assay and DNA sequencing. We found that the CC genotype of miR-34b/c rs4938723 was significantly associated with a decreased risk of IA compared with the TT genotype. Moreover, a significant gene interaction of the carriers with the combined genotypes of miR-34b/c rs4938723CC and TP53 Arg72Pro CG/CC/GG had a decreased risk of IA, compared with those carrying miR-34b/c rs4938723CT/TT
SYNTHESIS OF AROMATIC POLYESTERS FROM ESTERS OF DIPHENOLIC ACID AND ISOPHTHALOYL CHLORIDE BY INTERFACIAL POLYCONDENSATION
界面缩聚法制备间苯二甲酰双酚酸酯聚芳酯

ZHANG Ping,WU Linbo,BU Zhiyang,LI Bogeng,
张萍
,吴林波,卜志扬,李伯耿

高分子学报 , 2008,
Abstract: 以四丁基氯化铵为相转移催化剂,双酚酸甲酯或双酚酸乙酯与间苯二甲酰氯界面缩聚,合成得到了侧链含酯基的聚芳酯.在吡啶、三乙胺、碳酸氢钠、氢氧化钠中选择合适的催化剂,既可以发生聚合反应又不会使双酚酸酯的酯基发生水解.聚合反应在7种溶剂中进行,通过探讨聚合反应机理以解释溶剂对聚合反应产率以及聚合物特性黏数的影响.以二氯甲烷为溶剂,在优化的聚合条件下较高产率地得到了高特性黏数的聚合物.DSC及TGA分析表明,间苯二甲酰双酚酸酯类聚芳酯具有比间苯二甲酰双酚酸好的热稳定性,热分解温度可从200℃提高到300℃.
Functional polymorphism of the NFKB1 gene promoter is related to the risk of dilated cardiomyopathy
Bin Zhou, Li Rao, Ying Peng, Yanyun Wang, Yi Li, Linbo Gao, Yu Chen, Hui Xue, Yaping Song, Miao Liao, Lin Zhang
BMC Medical Genetics , 2009, DOI: 10.1186/1471-2350-10-47
Abstract: A total of 177 DCM patients and 203 control subjects were successfully investigated. The NFKB1 -94 insertion/deletion ATTG polymorphism was genotyped by using PCR-PAGE.Genotype frequency of NFKB1 -94 insertion/deletion ATTG polymorphism in DCM patients was significantly different from that in control subjects (P = 0.015) and the ATTG2 carrier (ATTG1/ATTG2 + ATTG2/ATTG2) was susceptible to DCM.Our data suggested that NFKB1 -94 insertion/deletion ATTG polymorphism is associated with DCM.Dilated cardiomyopathy (DCM), characterized by left ventricular dilation and systolic dysfunction, is the most common form of heart muscle disease, comprising 60% of the cases of identified cardiomyopathy [1]. This disorder is clinically heterogeneous, ranging from affected individuals with clinical presentations of severe symptoms, including heart failure and sudden death, and asymptomatic individuals. The clinical course of DCM, almost regardless of the underlying cause, may be progressive, with roughly 50% of individuals reported to die within 5 years of diagnosis without transplantation [1,2]. Although longer survival has been accomplished recently with improved medical therapies and interventions, early examinations are necessary to improve the DCM prognosis. The etiology of DCM is multifactorial and many different clinical conditions can lead to phenotype of DCM. It has become evident that genetic factors play an important role in the etiology and pathogenesis of DCM. To date, DCM-associated mutations in many different genes have been reported, but still these mutations explain only a minority of the etiology of DCM [3]. Some susceptibility genes have been shown to be associated with an increased risk of developing a DCM. These include HLA-DQA1*0501, HLA-DRB1*1401, exon 8 C/T of Endothelin receptor A, Leu10Pro of TGF-beta1, G994T of PAF acetyl hydrolase, MMP-3 5A/6A, and so on [4-6]. With more knowledge about susceptibility genes and pathways involved in DCM, strategies may emerg
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