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海上溢油模拟目标的日盲紫外反射特性研究

光谱学与光谱分析 2025年第3期45卷 637-644页

作者：龚博文毛石磊陈波中国科学院大学空间X射线-极紫外研究室北京101408 中国科学院长春光学精密机械与物理研究所吉林长春130033

海上溢油会对环境造成极大破坏,及时准确探测及识别对溢油的治理具有至关重要的作用。日盲紫外溢油监测受太阳背景辐射影响更小,可以提高溢油监测的准确率。研究设计并搭建水面油膜在日盲紫外、中波紫外和长波紫外波段反射光谱测试光路... 详细信息

海上溢油会对环境造成极大破坏,及时准确探测及识别对溢油的治理具有至关重要的作用。日盲紫外溢油监测受太阳背景辐射影响更小,可以提高溢油监测的准确率。研究设计并搭建水面油膜在日盲紫外、中波紫外和长波紫外波段反射光谱测试光路,对海洋溢油的四种模拟目标(95#汽油、35#柴油、20#柴油、轻质原油)展开反射光谱测试,分析了反射率随油膜厚度的变化趋势。采用单层膜特征矩阵模拟计算不同厚度油膜在不同波长下的反射率。实验与仿真结果表明,成品油和原油在日盲紫外波段的反射率均比海水更高,反射率随油膜厚度的改变近似周期性震荡最后趋近于纯油的反射率,周期大小和反射率峰值主要由油的复折射率和油膜厚度决定,实验与数值模拟结果相符。研究结果表明,水面油膜与水体背景在日盲紫外波段的反射光有较高的可区分度、反射率震荡变化的油膜厚度范围更小,采用主动式日盲紫外反射光谱探测海面溢油可以提高检测准确度,为全天时全天候溢油监测提供可能。

关键词：日盲紫外海水面油膜反射光谱油水反射对比度

Impacts of information about COVID-19 on pig farmers'production willingness and behavior:Evidence from China

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Journal of Integrative Agriculture 2024年第4期23卷 1429-1441页

作者： Huan Chen lei mao Yuehua Zhang School of Public Affairs Zhejiang UniversityHangzhou 310058China School of Insurance Central University of Finance and EconomicsBeijing 100081China Innovation Center of Yangtze River Delta Zhejiang UniversityJiaxing 314100China

This paper examines the impacts of information about COVID-19 on pig farmers'production willingness by using endorsement experiments and follow-up surveys conducted in 2020 and 2021 in *** results show that,first,farmers were less willing to scale up production when they received information about *** information in 2020 that the second wave of COVID-19 might occur without a vaccine reduced farmers'willingness to scale up by 13.4%,while the information in 2021 that COVID-19 might continue to spread despite the introduction of vaccine reduced farmers'willingness by 4.4%.Second,farmers whose production was affected by COVID-19 were considerably less willing to scale up,given the access to COVID-19 ***,farmers'production willingness can predict their actual production behavior.

关键词： COVID-19 randomized experiment information treatment production willingness

Performance Analysis and Prediction of Double-Server Polling System Based on BP Neural Network

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Chinese Journal of Electronics 2020年第6期29卷 1046-1053页

作者： YANG Zhijun mao lei GAN Jianhou DING Hongwei School of Information Science and Technology Yunnan University Educational Instruments and Facilities Service Center Educational Department of Yunnan Province Key Laboratory of Education Informalization for Nationalities of Ministry of Education Yunnan Normal University

To solve the poor performance of the single-server polling system in high traffic and the complex analysis of the multi-server polling system,a synchronous double-server polling system is proposed,and its performance is analyzed using a Backpropagation(BP) neural network prediction *** data are processed and analyzed,and a three-layer multiinput single-output BP network model is constructed to predict the performance of the polling system under different arrival rates of information *** the prediction stage,first,the data are processed and the average queue length under different information arrival rates is used to form a ***,a multiinput single-output BP neural network is constructed for *** results show that the algorithm can accurately predict the performance of the double-server polling system,thereby facilitating research regarding polling systems.

关键词： backpropagation neural nets queueing theory three-layer multiinput single-output BP network model prediction stage information arrival rates multiinput single-output BP neural network performance analysis single-server polling system complex analysis multiserver polling system synchronous double-server polling system backpropagation neural network prediction algorithm information packets Polling system BP neural network Prediction Average queue length Long-short term memory (LSTM)

Characterizing ship-induced hydrodynamics in a heavy shipping traffic waterway via intensified field measurements

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Water Science and Engineering 2020年第4期13卷 329-338页

作者： Li-lei mao Yi-mei Chen Xin Li Department of Port Waterway and Coastal EngineeringSoutheast UniversityNanjing 211189China

Ship-induced hydrodynamics play an important role in shaping the cross-sectional profile of inland waterways and produce a large amount of pressure on the fluvial *** study aimed at quantifying the characteristics of ship-induced waves and currents in a heavy shipping traffic waterway via intensified field measurements conducted in the Changzhou segment of the Grand Canal,in Jiangsu Province,*** on the processed hydrodynamic data,waves and currents caused by single ships and multiple ships were *** single ships,the shipinduced wave heights estimated with empirical formulas were not consistent with the *** by the loading conditions of barges,the drawdown height was characterized by the ratio of ship speed to its limit *** maximum non-dimensional ship-induced wave height was parameterized by a nonlinear combination of the depth Froude number and a blockage *** multiple ships,when ships closely followed each other or interlaced each other's paths,it was difficult to characterize the superposition of several ship *** magnitudes of current velocities induced by single ships and multiple ships were respectively nine and six times as large as those of natural *** may result in more severe sediment(re)suspension than natural flows.©2020 Hohai *** and hosting by Elsevier *** is an open access article under the CC BY-NC-ND license(http://***/licenses/by-nc-nd/4.0/).

关键词： Ship-induced waves Drawdown Field measurements Current velocity Sediment(re)suspension Grand Canal

Advances in preoperative assessment of liver function

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Hepatobiliary & Pancreatic Diseases International 2014年第4期13卷 361-370页

作者： Peng-lei Ge Shun-Da Du Yi-lei mao Department of Liver Surgery Peking Union Medical College (PUMC) Hospital Chinese Academy of Medical Sciences and PUMC

BACKGROUND： Postoperative liver failure remains a lifethreatening complication. Preoperative evaluation of liver function is essential in reducing the complications after hepatectomy. However, it is difficult to accurately evaluate liver function before surgery because of the limitations of the liver function tests available. Recent advances in liver function tests improved the ability to assess liver function. The present review was to analyze these methods and their *** SOURCES： MEDLINE was searched using the terms of ＂liver function test＂, ＂liver function evaluation＂ and ＂galactosyl serum albumin＂. Relevant articles published in English and Chinese from 1961 to 2014 were ***： Although serological tests are used frequently in practice, they reflect the degree of total liver damage or function, not the remnant of liver function. Child-Pugh score and model for end-stage liver disease（MELD） score assess whole liver function, and are particularly useful in determining whether patients with hepatocellular carcinoma and cirrhosis are candidates for resection or transplantation, but cannot determine the safe extent or removal. The indocyanine green and other metabolic quantitative liver function tests can evaluate functional hepatocytes, making them more accurate in predicting liver function. Computed tomography（CT）volumetry can provide anatomic information on the remnant liver volume but not on functional volume. 99mTc-galactosyl serum albumin scintigraphy, combined with single photon emission computed tomography, CT and three-dimensional reconstruction, may be a better quantitative measure of liver function, especially of remnant liver ***： Tests used to evaluate liver functional reserve and to predict surgical risk have limitations. 99mTc-galactosylserum albumin scintigraphy, which can more accurately evaluate the whole and regional liver function, may be promising in predicting resection margins and risks of liver failure.

关键词： liver function test hepatectomy asialoglycoprotein galactosyl serum albumin

Liver injury in COVID-19:What do we know now?

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Hepatobiliary & Pancreatic Diseases International 2020年第5期19卷 407-408页

作者： Hua-Yu Yang Bao Jin Yi-lei mao Department of Liver Surgery Peking Union Medical College(PUMC)HospitalPUMC&Chinese Academy of Medical Sciences(CAMS)Beijing 100730China

Coronavirus disease 2019(COVID-19)caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection has become a global *** large cohort studies have reported liver injury in COVID-19 ***,we reviewed the manifestations and causes of liver injury in COVID-19 patients and the effects of liver injury on the clinical outcomes based on the published literature.

关键词： acute respiratory injury

Novel 3D preclinical model systems with primary human liver cells: Recent progresses, applications and future prospects

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Hepatobiliary & Pancreatic Diseases International 2021年第2期20卷 105-107页

作者： Jian-Gang Zhang Hua-Yu Yang Yi-lei mao Department of Liver Surgery Peking Union Medical College(PUMC)HospitalPUMC&Chinese Academy of Medical Sciences(CAMS)Beijing 100730China

Liver plays a central role in various physiological functions,including metabolism,biliary secretion,production of plasma proteins,regulation of hormones as well as *** of its multidimensional functions,liver diseases such as viral hepatitis,non-alcoholic fatty liver disease,non-alcoholic steato-hepatitis,fibrosis and liver cancer may lead to serious consequences.

关键词： metabolism liver Liver

Research progress and prospects of circulating tumor cells in hepatocellular carcinoma

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Hepatobiliary & Pancreatic Diseases International 2022年第6期21卷 514-515页

作者： Chang-Can Li Hua-Yu Yang Yi-lei mao Department of Liver Surgery Peking Union Medical College(PUMC)HospitalPUMC&Chinese Academy of Medical Sciences(CAMS)Beijing 100730China

Hepatocellular carcinoma(HCC)is one of the most common cancers and is the second leading cause of cancer-related deaths worldwide[1,2].The main therapies for HCC include surgical re-section,local ablation,or liver transplantation,which are only applied to early-stage ***,most patients at the time of initial HCC diagnosis have already progressed to an advanced stage,and survival can only be prolonged finitely via palliative therapies,such as transarterial chemoembolization,systemic ther-apy with tyrosine kinase inhibitors,and selective internal radiation therapy[3,4].Moreover,as HCC has a high recurrence rate,the treatment efficacy is not satisfactory[5].Currently,the diagnosis and monitoring of HCC primarily depend on serum biomarker de-tection,pathological examination,and imaging *** serum markers display poor diagnostic performance,and imaging and pathological examinations have limitations in diagnostic accu-racy and sensitivity[6,7].Therefore,we urgently require better ap-proaches for the diagnosis and monitoring of HCC.

关键词： diagnosis arterial primarily

Combination of tumor-associated regulatory T cell deletion and PD-1/PD-L1 blockade: A promising immunotherapy for hepatocellular carcinoma?

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Hepatobiliary & Pancreatic Diseases International 2018年第2期17卷 93-94页

作者： Hua-Yu Yang Le-Jia Sun Yi-lei mao Department of Liver Surgery Peking Union Medical College (PUMC) Hospital PUMC & Chinese Academy of Medical Sciences

During the past decades,the treatment of hepatocellular carcinoma(HCC)has been limited to surgical resection and liver transplantation,but the prognosis is still ***,tumor immunotherapy,particularly immune checkpoints programmed cell death-1/programmed cell death ligand-1(PD-1/PD-L1)blockade,brings a breakthrough for HCC[1,2].However,anti-PD-1/PD-L1 immunotherapy is not satisfactory and the response rates were between 20%and 30%[3].How to improve the efficacy of PD-1/PD-L1blockade is the main issue.

关键词： HCC PD A promising immunotherapy for hepatocellular carcinoma Combination of tumor-associated regulatory T cell deletion and PD-1/PD-L1 blockade