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Effect of chip rate on the ranging accuracy in a regenerative pseudo-noise ranging system

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第2期12卷 132-139页

作者： Jian-wen JIANG Wei-jun YANG Chao-jie ZHANG xiao-jun jin Zhong-he jin Department of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

The ranging accuracy of a pseudo-noise ranging system is mainly decided by range jitter and time delay discrimination. Many factors can affect the ranging accuracy, one of which is the chip rate. In digital signal processing, the time delay discrimination and autocorrelation function of sampled ranging sequences of different chip rates are very different. An approximation simulation model is established according to an in-phase quadrature (I/Q) correlator which is used to evaluate the time delay. Simulation results of the range jitter and time delay discrimination show that the chip rate which provides a non-integer sample-to-chip rate ratio can achieve a higher ranging accuracy, and some test results validate the simulation model. In some design missions, the simulation results may help to select an optimum sample-to-chip rate ratio to satisfy the design requirement on the ranging accuracy.

关键词： Ranging accuracy Range jitter Time delay discrimination Sample-to-chip rate ratio Integration time Autocorrelation function Fractional chip period delay

An online error calibration method for spaceflight TT&C systems based on LEO-ground DDGPS

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Frontiers of Information Technology & Electronic Engineering 2019年第6期20卷 829-841页

作者： Qiao WANG xiao-jun jin Wei ZHANG Shi-ming MO Zhao-bin XU Zhong-he jin Micro-Satellite Research Center Zhejiang University Hangzhou 310027 China

To overcome the shortcomings of the traditional measurement error calibration methods for spaceflight telemetry, tracking and command(TT&C) systems, an online error calibration method based on low Earth orbit satellite-to-ground doubledifferential GPS(LEO-ground DDGPS) is proposed in this study. A fixed-interval smoother combined with a pair of forward and backward adaptive robust Kalman filters(ARKFs) is adopted to solve the LEO-ground baseline, and the ant colony optimization(ACO) algorithm is used to deal with the ambiguity resolution problem. The precise baseline solution of DDGPS is then used as a comparative reference to calibrate the systematic errors in the TT&C measurements, in which the parameters of the range error model are solved by a batch least squares algorithm. To validate the performance of the new online error calibration method, a hardware-in-the-loop simulation platform is constructed with independently developed spaceborne dual-frequency GPS receivers and a Spirent GPS signal generator. The simulation results show that with the fixed-interval smoother, a baseline estimation accuracy(RMS, single axis) of better than 10 cm is achieved. Using this DDGPS solution as the reference, the systematic error of the TT&C ranging system is effectively calibrated, and the residual systematic error is less than 5 cm.

关键词： Spaceflight low Earth orbit (LEO) Filter Optimization Calibration

Efficacy and safety of itraconazole as empirical antifungal therapy in febrile neutropenic patients with hematologic malignancies： an open-lable, multicenter, observational trial in a Chinese cohort

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Chinese Medical Journal 2011年第22期124卷 3670-3675页

作者： CHENG Shu ZHOU Jian-feng ZOU Ping HUANG xiao-jun jin Jie SHEN Zhi-xiang Department of Hematology Shanghai Ruijin Hospital Medical School of Shanghai Jiao Tong University Shanghai 200025 China

Background Invasive fungal infection （IFI） is a common and fatal complication in neutropenic patients with hematological malignancy. Empirical antifungal therapy is widely used in practice due to the difficulty of pathogens determination and illness of the hosts. The aim of this study was to evaluate the efficacy and safety of itraconazole as empirical antifungal therapy for persistent fever in neutropenic patients with hematologic malignancies. Methods Two hundred and seventy-four patients with hematologic malignancies who had suspected fungal infections were enrolled in 18 centers across China between April 2008 and April 2009. Empirical antifungal therapy with intravenous itraconazole 200 mg twice daily was given for the first two days, followed by 200 mg once daily for the next 12 days. Oral itraconazole solution was sequential for follow-up therapy if necessary. Five composite end points were evaluated for the response, which was more restrictive and adopted for the first time in such study in China. Results The intent-to-treat analysis included data from 274 patients （full analysis set, FAS）, of whom 248 were included as the per-protocol population （PPS）. As the composite end point of five indices was concerned, the overall response rate was 43.4%. Seperately, defervescence was achieved in 90% of patients in which 55.5% occured during neutropenia. The mean time to defervescence was 2.71 days. Absence of breakthrough IFI during drug administration or within the first 7 days after study completion was observed in 71.5% of patients. Fifty-five point five percent patients with IFI at baseline was successfully treated. Ninety point five percent patients survived for at least 7 days after completing the study. PPS analysis revealed that the duration of neutropenia 〉10 days was a statistically significant negative predictor for the response. The withdrawal rate due to drug-related toxicity or lack of efficacy was 11.0%. The incidence of adverse events was 22.6%, in w

关键词： itraconazole, hematologic malignancy febrile neutropenia empirical therapy

Determination of Carbon by Means of Microwave Plasma Torch Atomic Emission Spectrometry

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Chemical Research in Chinese Universities 1996年第1期12卷 32-36页

作者： ZHANG Han-qi YUAN Xiang-lin YE Dong-mei ZHAO xiao-jun and jin Qin-han (Department Of Chemistry, Jilin University, Changchun, 130023)ZHU Zhi-ping(Department of Chemistry, Northeast Normal University, Changchun, 130024) JILIN UNIV DEPT CHEM CHANGCHUN 130023 PEOPLES R CHINA NE NORMAL UNIV DEPT CHEM CHANGCHUN 130024 PEOPLES R CHINA

The determination of carbon by means of microwave plasma torch atomic emission spectrometry(MPT-AES) was studied. Aqueous samples were introduced with a pneumatic nebulization system. The detection limit for carbon wa... 详细信息

关键词： Microwave plasma torch Atomic emission spectrometry Carbon

Angiomyolipoma with minimal fat： differentiation from renal cell carcinoma at helical CT

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Chinese Medical Journal 2013年第5期126卷 991-992页

作者： ZHAO xiao-jun PU jin-xian PING Ji-gen ZANG jin LU Yong XI Qi-lin HOU Wen-jie Department of Urology I:irst Affiliated llospital Soochow University Suzhou Jiangsu 215006 China

Renal cell carcinoma （RCC） accounts for 85%-90% of -all kidney tumors. Although the majority of renal tumors in surgical series are malignant, a number of patients do undergo nephrectomy tbr benign lesions,Such minimal l：at angiomyolipomas （AML） are visually indistinguishable from RCC and present particular diagnostic difficulties. In this study, CT number in region of whole mass （ROW） is advocated.

关键词： CT scan renal cell carcinoma angiomyolipomas

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Lurie型直接控制系统的绝对稳定性

控制理论与应用 2007年第4期24卷 665-668页

作者：赵立英肖劲军刘贺平北京科技大学应用科学学院北京100083 北京科技大学信息工程学院北京100083

Lurie型控制系统是一类非常典型的非线性控制系统,具有广泛的实际工程应用背景.本文利用Popov频域法,研究了一类Lurie型直接控制系统的绝对稳定性.在系统矩阵无对角线相等情形假设的一般条件下,给出了该类系统绝对稳定的一些充分必要条... 详细信息

Lurie型控制系统是一类非常典型的非线性控制系统,具有广泛的实际工程应用背景.本文利用Popov频域法,研究了一类Lurie型直接控制系统的绝对稳定性.在系统矩阵无对角线相等情形假设的一般条件下,给出了该类系统绝对稳定的一些充分必要条件.这些结论推广了前人所取得的研究成果.

关键词： Lurie型控制系统 Popov频率判据绝对稳定性

High mobility group box 1 in the central nervous system:regeneration hidden beneath inflammation

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Neural Regeneration Research 2025年第1期20卷 107-115页

作者： Hanki Kim Bum jun Kim Seungyon Koh Hyo jin Cho Xuelian jin Byung Gon Kim jun Young Choi Department of Brain Science Ajou University School of MedicineSuwonSouth Korea Department of Biomedical Sciences Ajou University Graduate School of MedicineSuwonSouth Korea Department of Neurology Ajou University School of MedicineSuwonSouth Korea Department of Geriatrics The Affiliated Suqian First People’s Hospital of Nanjing Medical UniversitySuqianJiangsu ProvinceChina

High-mobility group box 1 was first discovered in the calf thymus as a DNA-binding nuclear protein and has been widely studied in diverse fields,including neurology and ***-mobility group box 1 in the extracellular space functions as a pro-inflammatory damage-associated molecular pattern,which has been proven to play an important role in a wide variety of central nervous system disorders such as ischemic stroke,Alzheimer’s disease,frontotemporal dementia,Parkinson’s disease,multiple sclerosis,epilepsy,and traumatic brain *** drugs that inhibit high-mobility group box 1 as a damage-associated molecular pattern,such as glycyrrhizin,ethyl pyruvate,and neutralizing anti-high-mobility group box 1 antibodies,are commonly used to target high-mobility group box 1 activity in central nervous system *** it is commonly known for its detrimental inflammatory effect,high-mobility group box 1 has also been shown to have beneficial pro-regenerative roles in central nervous system *** this narrative review,we provide a brief summary of the history of high-mobility group box 1 research and its characterization as a damage-associated molecular pattern,its downstream receptors,and intracellular signaling pathways,how high-mobility group box 1 exerts the repair-favoring roles in general and in the central nervous system,and clues on how to differentiate the pro-regenerative from the pro-inflammatory *** targeting high-mobility group box 1 in the central nervous system may benefit from differentiating between the two functions rather than overall suppression of high-mobility group box 1.

关键词： central nervous system damage-associated molecular pattern ethyl pyruvate glycyrhizzin high mobility group box 1 inflammation neural stem cells neurodevelopment oligodendrocyte progenitor cells redox status regeneration

Preliminary Design of a System for Picking up Audio-Signals From Bubble Detectors GAO Si-ze1,NI Bang-fa,ZHANG Gui-ying,xiao Cai-jin,LIU Cun-xiong, CHEN Zhe1,NIE Peng,LIU Chao1,ZHAO Chang-jun (*** of Physics Science and Engineering Technology,Guang

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Preliminary Design of a System for Picking up Audio-Signals ...

Optimal Procurement Contract between Contractor and Supplier in Large-Scale Projects

作者： GAO Si-ze NI Bang-fa ZHANG Gui-ying xiao Cai-jin LIU Cun-xiong CHEN Zhe NIE Peng LIU Chao ZHAO Chang-jun College of Physics Science and Engineering Technology Guangxi University

This system is designed to pick up sound signals from large volume,low-threshold energy, low-background superheated droplets bubble detectors.A sound-sensitive bubble detector is composed of a container filled with a mixture of superheated droplets and gel,a temperature and pressure control system,and an audio acquisition system attached on the outer surface of the *** superheated droplets are in a metastable and superheated state at ambient temperature and *** the outside

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Optimal Procurement Contract between Contractor and Supplier...