检索结果-南通市图书馆

A peak enhancement of frequency response of waveguide integrated silicon-based germanium avalanche photodetector

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Semiconductors 2024年第7期45卷 61-68页

作者： linkai Yi Daoqun liu Wenzheng Cheng Daimo li Guoqi Zhou Peng Zhang Bo Tang Bin li Wenwu Wang Yan Yang zhihua li Institute of Microelectronics Chinese Academy of SciencesBeijing 100029China School of Electronic Electrical and Communication Engineering University of Chinese Academy of SciencesBeijing 100049China

Avalanche photodetectors(APDs) featuring an avalanche multiplication region are vital for reaching high sensitivity and responsivity in optical transceivers. Waveguide-coupled Ge-on-Si separate absorption, charge, and multiplication(SACM)APDs are popular due to their straightforward fabrication process, low optical propagation loss, and high detection sensitivity in optical communications. This paper introduces a lateral SACM Ge-on-Si APD on a silicon-on-insulator(SOI) wafer, featuring a 10 μm-long, 0.5 μm-wide Ge layer at 1310 nm on a standard 8-inch silicon photonics platform. The dark current measures approximately 38.6 μA at-21 V, indicating a breakdown voltage greater than-21 V for the device. The APDs exhibit a unitgain responsivity of 0.5 A/W at-10 V. At-15 V, their responsivity reaches 2.98 and 2.91 A/W with input powers of-10 and-25 dBm, respectively. The device's 3-dB bandwidth is 15 GHz with an input power of-15 dBm and a gain is 11.68. Experimental results show a peak in impedance at high bias voltages, attributed to inductor and capacitor(LC) circuit resonance, enhancing frequency response. Furthermore, 20 Gbps eye diagrams at-21 V and-9 dBm input power reveal signal to noise ratio(SNRs) of 5.30. This lateral SACM APD, compatible with the stand complementary metal oxide semiconductor(CMOS) process,shows that utilizing the peaking effect at low optical power increases bandwidth.

关键词： photodetectors optical communications responsivity 3-dB bandwidth

An accurate diagnostic approach for urothelial carcinomas based on novel dual methylated DNA markers in small-volume urine

在线全文

学校读者我要写书评

暂无评论

Chinese Medical Journal 2024年第2期137卷 232-234页

作者： Yucai Wu Di Cai Jian Fan Chang Meng Shiming He zhihua li lianghao Zhang Kunlin Yang Aixiang Wang Xinfei li Yicong Du Shengwei Xiong Mancheng Xia Tingting li Lanlan Dong YanqingGong liqun Zhou Xuesong li Department of Urology Peking University First HospitalBeijing 100034China Institute of Urology Peking UniversityBeijing 100034China National Urological Cancer Center Beijing 100034China Urogenital Diseases(Male)Molecular Diagnosis and Treatment Center Peking UniversityBeijing 100034China Wuhan Ammunition life-tech Company Ltd.WuhanHubei 430200China

Diagnostic methods for urothelial carcinomas(UCs)are often invasive or have suboptimal *** of exfoliated cell DNA or cell-free DNA in urine has shown great promise in the diagnosis of ***,most current studies have focused on bladder cancer(BCa),and only a few high-plex methylated DNA panels based on large-volume urine have been reported to exhibit both high sensitivity and specificity.[1,2]The purpose of this study was to identify universal biomarkers for BCa and upper tract urothelial carcinoma(UTUC)using a small volume of *** developed a dual-target diagnostic panel comprising the novel marker AL021918.2 and the well-known BCa biomarker Vimentin(VIM).This panel can accurately detect UCs using only 1.8 mL of full-voided urine.

关键词： urine bladder diagnosis

基于深度强化学习的多用户计算卸载优化模型和算法

在线全文

学校读者我要写书评

暂无评论

电子与信息学报 2024年第4期46卷 1321-1332页

作者：李志华余自立江南大学人工智能与计算机学院无锡214122

在移动边缘计算(MEC)密集部署场景中,边缘服务器负载的不确定性容易造成边缘服务器过载,从而导致计算卸载过程中时延和能耗显著增加。针对该问题,该文提出一种多用户计算卸载优化模型和基于深度确定性策略梯度(DDPG)的计算卸载算法。首... 详细信息

在移动边缘计算(MEC)密集部署场景中,边缘服务器负载的不确定性容易造成边缘服务器过载,从而导致计算卸载过程中时延和能耗显著增加。针对该问题,该文提出一种多用户计算卸载优化模型和基于深度确定性策略梯度(DDPG)的计算卸载算法。首先,考虑时延和能耗的均衡优化建立效用函数,以最大化系统效用作为优化目标,将计算卸载问题转化为混合整数非线性规划问题。然后,针对该问题状态空间大、动作空间中离散和连续型变量共存,对DDPG深度强化学习算法进行离散化改进,基于此提出一种多用户计算卸载优化方法。最后,使用该方法求解非线性规划问题。仿真实验结果表明,与已有算法相比,所提方法能有效降低边缘服务器过载概率,并具有很好的稳定性。

关键词：移动边缘计算计算卸载深度强化学习资源分配

在线全文

学校读者我要写书评

暂无评论

基于SSTDR的光伏连接器故障检测

高电压技术 2024年第4期50卷 1508-1517页

作者：李智华张豪吴春华汪飞上海大学上海市电站自动化技术重点实验室上海200444

随着运行时间的增长,光伏连接器会出现氧化、老化、松动等现象,易导致接触不良、发热等问题,最终可能引起断路、电弧等故障,对光伏系统的高效、安全运行造成不良影响。由于光伏连接器故障会引起其等效阻抗的变化,该文采用扩频时域反射法... 详细信息

随着运行时间的增长,光伏连接器会出现氧化、老化、松动等现象,易导致接触不良、发热等问题,最终可能引起断路、电弧等故障,对光伏系统的高效、安全运行造成不良影响。由于光伏连接器故障会引起其等效阻抗的变化,该文采用扩频时域反射法(spread spectrum time domain reflectometry,SSTDR)来进行检测:通过向光伏连接器所在的光伏组件串注入正弦高频信号调制的伪随机序列序列测试信号,分析入射信号与反射信号的相关特性,再与健康状态下的特性进行比较,来实现光伏连接器故障在线诊断。对此进行仿真计算并在4块光伏板组成的光伏组串中进行实验,发现开路故障时包络面积最大可达到5×10^(5),而脱离故障时包络面积最小为0.8×10^(5),二者皆远大于健康时的包络面积0.07×10^(5),可有效诊断光伏连接器是否发生故障。

关键词：光伏连接器 SSTDR 故障检测传输线特征阻抗

维普期刊数据库博看期刊

面向物联网僵尸网络多阶段攻击的异常流量检测方法

在线全文

学校读者我要写书评

暂无评论

计算机科学 2024年第8期51卷 379-386页

作者：陈亮李志华江南大学人工智能与计算机学院江苏无锡214112

针对如何从海量的网络流量数据中高效检测出物联网僵尸网络多阶段攻击行为,提出了一种基于多尺度混合残差网络(Multi-scale Hybrid Residual Network,MHRN)的物联网僵尸网络攻击检测(IoT Botnet Attack Detection based on MHRN,IBAD-MH... 详细信息

针对如何从海量的网络流量数据中高效检测出物联网僵尸网络多阶段攻击行为,提出了一种基于多尺度混合残差网络(Multi-scale Hybrid Residual Network,MHRN)的物联网僵尸网络攻击检测(IoT Botnet Attack Detection based on MHRN,IBAD-MHRN)方法。首先,为了减少检测模型的计算参数,在数据预处理中提出基于方差阈值法的特征选择(Feature Selection based on Variance Threshold,FS-VT)算法;其次,采取一种将数据样本转换为图像样本的数据图像化处理策略,充分挖掘深度学习模型的潜能;然后,为了弥补传统僵尸网络检测模型表征能力有限的不足,提出了一种基于多尺度混合残差网络的物联网僵尸网络多阶段攻击检测模型,该模型通过混合方式融合了不同尺度深度提取的特征信息,再通过残差连接消除网络加深造成的网络退化影响;最后,集成上述模型和算法,进一步提出了一种物联网僵尸网络攻击检测方法IBAD-MHRN。实验结果表明,IBAD-MHRN方法的检测准确率和F1值均达到了99.8%,与表现较好的卷积神经网络方法相比在准确率和F1值上分别有0.14%和0.36%的提升,能够有效且高效地检测物联网僵尸网络多阶段攻击。

关键词：物联网僵尸网络方差阈值法残差网络多阶段攻击

全移相双有源全桥直流变换器的瞬态电流偏置抑制策略

在线全文

学校读者我要写书评

暂无评论

电工技术学报 2024年第4期39卷 1116-1131页

作者：吴春华陈修淋李智华汪飞上海大学电气工程系上海市电站自动化技术重点实验室上海200444

针对双有源全桥(DAB)直流变换器在功率突变时产生的电流偏置问题,该文提出一种新的瞬态直流偏置抑制策略。首先,以基于全移相调制的双有源全桥直流变换器为研究对象,分析DAB变换器产生直流偏置的原因及危害。然后,在全局电感电流应力最... 详细信息

针对双有源全桥(DAB)直流变换器在功率突变时产生的电流偏置问题,该文提出一种新的瞬态直流偏置抑制策略。首先,以基于全移相调制的双有源全桥直流变换器为研究对象,分析DAB变换器产生直流偏置的原因及危害。然后,在全局电感电流应力最优结果的基础上,对功率在四个工作区域突变时产生的瞬态直流偏置问题进行详细分析,推导各种电流突变情况下的直流偏置表达式,并据此提出一种新的过渡态引入方法,对于不同的功率突变状态可以得到统一的过渡移相角表达式,简化了控制过程。接着,根据所得过渡态结果,提出统一的载波调制方法,并对调制策略的适用性进行分析。最后,通过实验平台验证了所提方法可以有效消除功率突变时产生的电流偏置。

关键词：双有源全桥(DAB)变换器功率突变瞬态直流偏置抑制全移相控制载波调制

在线全文

学校读者我要写书评

暂无评论

人偏肺病毒融合蛋白疫苗研究进展

中华微生物学和免疫学杂志 2024年第7期44卷 608-613页

作者：王怡丹李智华毕研伟李倩倩中国医学科学院医学生物学研究所病原体感染防控教育部重点实验室(北京协和医学院)昆明650031 云南大学生命科学学院昆明650091

人偏肺病毒是一种常见的呼吸道病毒,属肺炎病毒科偏肺病毒属,2001年首次发现于荷兰,全球广泛分布,能够反复感染婴幼儿、老年人及免疫功能低下者,并引起急性呼吸道感染。目前,尚无有效的预防性疫苗批准上市。本文主要概述人偏肺病毒的病... 详细信息

人偏肺病毒是一种常见的呼吸道病毒,属肺炎病毒科偏肺病毒属,2001年首次发现于荷兰,全球广泛分布,能够反复感染婴幼儿、老年人及免疫功能低下者,并引起急性呼吸道感染。目前,尚无有效的预防性疫苗批准上市。本文主要概述人偏肺病毒的病毒学和流行病学特征,介绍其潜在疫苗关键免疫原融合蛋白的结构和抗原位点,以及基于融合蛋白设计的亚单位疫苗、减毒活疫苗和核酸疫苗研究的最新进展。

关键词：人偏肺病毒疫苗融合蛋白抗原设计

在线全文

学校读者我要写书评

暂无评论

云数据中心能耗感知的虚拟机优化放置方法

计算机应用 2024年第S1期44卷 156-163页

作者：苏苗苗李志华江南大学人工智能与计算机学院江苏无锡214122

随着云数据中心规模的不断扩大,能耗快速增长、资源利用率低的问题日益突出,导致云数据中心运行成本的增加和资源的浪费。针对该问题,提出一种基于改进多目标粒子群优化的能耗和资源感知的虚拟机放置(IMPSO-ERVMP)方法。首先,以最小化... 详细信息

随着云数据中心规模的不断扩大,能耗快速增长、资源利用率低的问题日益突出,导致云数据中心运行成本的增加和资源的浪费。针对该问题,提出一种基于改进多目标粒子群优化的能耗和资源感知的虚拟机放置(IMPSO-ERVMP)方法。首先,以最小化能耗、剩余资源均衡度和服务等级协议(SLA)违背率为优化目标,构建多目标虚拟机放置优化模型;其次,利用Tent映射对多目标粒子群优化(PSO)算法的种群进行初始化以提高初始解的质量,并利用余弦变换动态调整飞行参数以平衡算法的探索和开发能力,同时在位置更新中引入柯西变异机制对最优粒子的位置向量进行扰动;最后,利用改进的多目标PSO算法求解模型的Pareto最优解,得到最佳虚拟机放置序列。仿真结果表明,IMPSO-ERVMP方法与所参考的虚拟机放置方法相比,在能耗、资源利用率以及服务质量评价指标上表现良好。

关键词：云数据中心多目标优化多目标粒子群优化虚拟机放置服务质量

The real-world study of the clinical characteristics, diagnosis, and treatment of advanced pancreatic cancer in China

在线全文

学校读者我要写书评

暂无评论

胰腺病学杂志(英文) 2024年第1期7卷 1-9页

作者： Cui Jiujie Fu Qihan Chen Xiaobing Wang Yanling li Qi Wang Feng li zhihua Dai Guanghai Wang Yusheng Zhang Hongmei liang Houjie Zhou Jun Yang liu Wang Fenghua Zheng Leizhen Chen Xiaofeng Gong Ping liu Jiang Yuan Ying Wang lin Cheng Yuejuan Zhang Jun Zhou Yuhong Guo Weijian Zhan Xianbao Zou Zhengyun li Da Zeng Shan li Enxiao li Zhiwei Teng Zan Cao Dan Kan Jie Xiong Jianping Quan Ming Yao Jiayu Yang Haiyan Wang liwei Department of Medical Oncology Renji Hospital School of Medicine Shanghai Jiao Tong University Shanghai China Department of Medical Oncology The First Affiliated Hospital College of Medicine Zhejiang University Hangzhou China Department of Medical Oncology Affiliated Cancer Hospital of Zhengzhou University Henan Cancer Hospital Zhengzhou China Department of Medical Oncology Shanghai General Hospital Shanghai Jiao Tong University Shanghai China Department of Medical Oncology The First Affiliated Hospital of Zhengzhou University Zhengzhou China Department of Medical Oncology Sun Yat-sen Medical Hospital Sun Yat-sen University Guangzhou China Medical Oncology Chinese PLA General Hospital Beijing China Department of Gastrointestinal Oncology Shanxi Provincial Cancer Hospital Affiliated to Shanxi Medical University Taiyuan China Department of Clinical Oncology Xijing Hospital Air Force Medical University Xi’an China Department of Oncology and Southwest Cancer Center Southwest Hospital Third Military Medical University (Army Military Medical University) Chongqing China Department of Gastrointestinal Oncology Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/ Beijing) Peking University Cancer Hospital &amp Institute Beijing China Cancer Center Department of Medical Oncology Zhejiang Provincial People’s Hospital People’s Hospital of Hangzhou Medical College Hangzhou China Department of Medical Oncology Sun Yat-sen University Cancer Center State Key Laboratory of Oncology in South China Collaborative Innovation Center for Cancer Medicine Guangzhou Guangdong China Oncology Department Xin Hua Hospital Affiliated to Shanghai JiaoTong University School of Medicine Shanghai China Department of Oncology the First Affiliated Hospital with Nanjing Medical University Nanjing China Department of Oncology The First Affiliated Hospital School of Medicine Shihezi University Shihezi China Department of Oncology People’s Hospital of Xinjia

Objective: Real-world diagnostic and treatment data for pancreatic cancer in China are lacking. As such, the present study investigated the clinical characteristics, diagnosis, and treatment of advanced pancreatic cancer (including locally advanced and metastatic disease) in the Hospital-based Advanced Pancreatic Cancer Cohort in China of the China Pancreas Data Center ***: A total of 5349 Chinese patients with advanced pancreatic cancer were identified from a database. The entire course of real-world pancreatic cancer management was ***: The proportion of patients with advanced pancreatic cancer was higher among males than females (62.4% vs 37.6%, respectively). Patients typically had a history of hypertension (30.8%), diabetes (21.6%), and cholangitis (20.2%). Abdominal pain (51.6%), abdominal distension (27.1%), jaundice (20.1%), and weight loss (16.3%) were the main symptoms observed in patients with advanced pancreatic cancer in this cohort. Serum carbohydrate antigen (CA)19-9 is one of the most common tumor markers. In the present study, 2562 patients underwent first-line therapy. The median progression-free survival (PFS) for patients undergoing first-line therapy was 4.1 months. The major options for first-line therapy included gemcitabine (GEM) plus S-1 (GS/X) (23.4%), nab-paclitaxel plus GEM (AG) (18.1%), oxaliplatin, irinotecan, and leucovorin-modulated fluorouracil (FOLFIRINOX; 11.9%), nab-paclitaxel plus S-1 (AS) (8.9%), and GEM combined with oxaliplatin/cisplatin (GEMOX/GP) (7.6%). The AS and GS/X regimens were associated with the highest PFS ***: This is the first study to report multicenter, real-world data regarding advanced pancreatic cancer in China. Results revealed that real-world treatment options differed from guideline recommendations, and PFS was shorter than that in previously reported data. Improving intelligent follow-up systems and standardizing diagnosis and treatment of pancreatic cancer is recomm

关键词： Advanced pancreatic cancer China Pancreas Data Center Chinese First-line regimens Real-world study