检索结果-南通市图书馆

Inaudible Sound Covert Channel with Anti-Jamming Capability: Attacks vs. Countermeasure

Journal of Electronic Science and Technology 2022年第4期20卷 396-415页

作者： Xiao-Hang Wang Shou-bin Li Ying-Tao Jiang Amit Kumar Singh bi-Yun Ma le-Tian Huang Mei Yang Fen Guo School of Cyber Science and Technology Zhejiang UniversityHangzhou 310012 ZJU-Hangzhou Global Scientific and Technological Innovation Center Hangzhou 310012 School of Software Engineering South China University of TechnologyGuangzhou 510006 Department of Electrical and Computer Engineering University of NevadaLas Vegas 89154 School of Computer Science and Electronic Engineering University of EssexColchester CO43SQ School of Electronics and Information Engineering South China University of TechnologyGuangzhou 510640 School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 610054

When an inaudible sound covert channel(ISCC)attack is launched inside a computer system,sensitive data are converted to inaudible sound waves and then *** receiver at the other end picks up the sound signal,from which the original sensitive data can be *** a forceful countermeasure against the ISCC attack,strong noise can be used to jam the channel and literally shut down any possible sound data *** this paper,enhanced ISCC is proposed,whose transmission frequency can be dynamically ***,if the transmitter detects that the covert channel is being jammed,the transmitter and receiver both will switch to another available frequency and re-establish their communications,following the proposed communications *** results show that the proposed enhanced ISCC can remain connected even in the presence of a strong jamming noise ***,a detection method based on frequency scanning is proposed to help to combat such an anti-jamming sound *** the proposed countermeasure,the bit error rate(BER)of the data communications over enhanced ISCC soars to more than 48%,essentially shutting down the data transmission,and thus neutralizing the security threat.

关键词： Countermeasure inaudible sound covert channel(ISCC)

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Survival benefits and disparities in radiation therapy for elderly patients with pancreatic ductal adenocarcinoma

引用

World Journal of Gastrointestinal Oncology 2023年第1期15卷 155-170页

作者： bi-Yang Cao Qian-Qian Wang le-Tian Zhang Chen-Chen Wu Fang Tong Wei Yang Jing Wang Department of Radiation Oncology First Medical Center of Chinese PLA General HospitalBeijing 100853China Medical School of Chinese PLA Beijing 100853China

BACKGROUND older patients represent a unique subgroup of the cancer patient population,for which the role of cancer therapy requires special ***,the outcomes of radiation therapy(RT)in elderly patients with pancreatic ductal adenocarcinoma(PDAC)are not well-defined in the *** To explore the use and effectiveness of RT in the treatment of elderly patients with PDAC in clinical *** Data from patients with PDAC aged≥65 years between 2004 and 2018 were collected from the Surveillance,Epidemiology,and End Results *** logistic regression analysis was performed to determine factors associated with RT *** survival(OS)and cancer-specific survival(CSS)were evaluated using the Kaplan–Meier method with the log-rank *** and multivariate analyses with the Cox proportional hazards model were used to identify prognostic factors for *** score matching(PSM)was applied to balance the baseline characteristics between the RT and non-RT *** analyses were performed based on clinical *** A total of 12245 patients met the inclusion criteria,of whom 2551(20.8%)were treated with RT and 9694(79.2%)were *** odds of receiving RT increased with younger age,diagnosis in an earlier period,primary site in the head,localized disease,greater tumor size,and receiving chemotherapy(all Ple(median OS:14.0 vs 11.0 mo;HR for OS:0.818,95%CI:0.768–0.872,Pled that the survival benefits(OS and CSS)of RT were more significant in patients aged 65 to 80 years,in regional and distant stages,with no surgery,and receiv

关键词： Pancreatic ductal adenocarcinoma Elderly Radiotherapy Effectiveness Disparities Surveillance,Epidemiology,and End Results

来源：

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

基于轻量化高效层聚合网络的黄花成熟度检测方法

引用

农业机械学报 2024年第2期55卷 268-277页

作者：吴利刚陈乐周倩史建华马宇波山西大同大学机电工程学院大同037003 山西大同大学煤炭工程学院大同037003 山西大同大学商学院大同037003 山西大同大学物理与电子科学学院大同037003

针对黄花传统人工识别效率低,辨识标准不统一的问题,提出基于轻量化和高效层聚合过渡网络的黄花成熟度识别方法LSEB YolO v7。首先,引入轻量化卷积对高效层聚合网络和过渡模块进行轻量化处理,减少模型计算量。其次,在特征提取与特征融... 详细信息

针对黄花传统人工识别效率低,辨识标准不统一的问题,提出基于轻量化和高效层聚合过渡网络的黄花成熟度识别方法LSEB YolO v7。首先,引入轻量化卷积对高效层聚合网络和过渡模块进行轻量化处理,减少模型计算量。其次,在特征提取与特征融合网络之间增加通道注意力机制,提升模型检测性能。最后,在特征融合网络中,优化通道信息融合方式,使用双向特征金字塔网络替换Concatenate,增加信息融合通道,持续提升模型性能。实验结果表明:与原始模型相比,在黄花成熟度检测中,改进后的LSEB YolO v7模型参数量和浮点运算量分别减少约2.0×10^(6)和7.7×10^(9)。训练时长由8.025 h降低至7.746 h,模型体积压缩约4 MB。同时,训练精确率和召回率分别提升约0.64个百分点和0.14个百分点,mAP@0.5和mAP@0.5:0.95分别提升约1.84个百分点和1.02个百分点。此外,调和均值性能保持不变,均为84.00%。LSEB YolO v7算法可均衡模型复杂性与性能,为黄花成熟度检测和智能化采摘设备提供技术支持。

关键词：黄花成熟度深度学习注意力机制信息融合机制轻量化

来源：

维普期刊数据库博看期刊

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Improved Design of a 25 MW Gas Turbine Plant Using Combined Cycle Application

引用

Journal of Power and Energy Engineering 2015年第8期3卷 1-14页

作者： Barinaadaa Thaddeus lebele-Alawa Anthony Kpegele le-ol Department of Mechanical Engineering Rivers State University of Science and Technology Port Harcourt Nigeria

This paper presents the improved design of a 25 MW gas turbine power plant at Omoku in the Niger Delta area of Nigeria, using combined cycle application. It entails retrofitting a steam bottoming plant to the existing 25 MW gas turbine plant by incorporating a heat recovery steam generator. The focus is to improve performance as well as reduction in total emission to the environment. Direct data collection was performed from the HMI monitoring screen, log books and manufacturer’s manual. Employing the application of MATLAB, the thermodynamics equations were modeled and appropriate parameters of the various components of the steam turbine power plant were determined. The results show that the combined cycle system had a total power output of 37.9 MW, made up of 25.0 MW from the gas turbine power plant and 12.9 MW (an increase of about 51%) from the steam turbine plant, having an HRSG, condenser and feed pump capacities of 42.46 MW, 29.61 MW and 1.76 MW respectively. The condenser cooling water parameters include a mass flow of 1180.42 kg/s, inlet and outlet temperatures of 29.8°C and 35.8°C respectively. The cycle efficiency of the dry mode gas turbine was 26.6% whereas, after modification, the combined cycle power plant overall efficiency is 48.8% (about 84% increases). Hence, SIEMENS steam turbine product of MODEL: SST-150 was recommended as the steam bottoming plant. Also the work reveals that a heat flow of about 42.46 MW which was otherwise being wasted in the exhaust gas of the 25 MW gas turbine power plant could be converted to 12.9 MW of electric power, thus reducing the total emission to the environment.

关键词： Gas Turbine Steam Turbine HRSG Combined Cycle Power Output Overall Efficiency Condenser Cooling Water

来源：

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

Risk factors,prognostic predictors,and nomograms for pancreatic cancer patients with initially diagnosed synchronous liver metastasis

引用

World Journal of Gastrointestinal Oncology 2023年第1期15卷 128-142页

作者： bi-Yang Cao Fang Tong le-Tian Zhang Yi-Xin Kang Chen-Chen Wu Qian-Qian Wang Wei Yang JingWang Department of Radiation Oncology First Medical Center of Chinese PLA General HospitalBeijing 100853China Medical School of Chinese PLA Beijing 100853China

BACKGROUND Liver metastasis(LM)remains a major cause of cancer-related death in patients with pancreatic cancer(PC)and is associated with a poor ***,identifying the risk and prognostic factors in PC patients with LM(PCLM)is essential as it may aid in providing timely medical interventions to improve the prognosis of these ***,there are limited data on risk and prognostic factors in PCLM *** To investigate the risk and prognostic factors of PCLM and develop corresponding diagnostic and prognostic *** Patients with primary PC diagnosed between 2010 and 2015 were reviewed from the Surveillance,Epidemiology,and Results *** factors were identified using multivariate logistic regression analysis to develop the diagnostic *** least absolute shrinkage and selection operator Cox regression model was used to determine the prognostic factors needed to develop the prognostic *** performance of the two nomogram models was evaluated using receiver operating characteristic(ROC)curves,calibration plots,decision curve analysis(DCA),and risk subgroup *** Kaplan-Meier method with a logrank test was used for survival *** We enrolled 33459 patients with PC in this *** them,11458(34.2%)patients had LM at initial *** at diagnosis,primary site,lymph node metastasis,pathological type,tumor size,and pathological grade were identified as independent risk factors for LM in patients with ***>70 years,adenocarcinoma,poor or anaplastic differentiation,lung metastases,no surgery,and no chemotherapy were the independently associated risk factors for poor prognosis in patients with *** C-index of diagnostic and prognostic nomograms were 0.731 and 0.753,*** two nomograms could accurately predict the occurrence and prognosis of patients with PCLM based on the observed analysis results of ROC curves,calibration plots,and DCA *** prognostic nomogram could strati

关键词： Pancreatic neoplasms Neoplasm metastasis Liver Prognosis Nomograms Surveillance,Epidemiology,and End Result program

来源：

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

Molecular Identification and Expression Analysis of GhHYDRA1 Gene, a Homologue of HYDRA1 Gene From Upland Cotton (Gossypium hirsutum L.)

引用

Agricultural Sciences in China 2011年第1期10卷 41-48页

作者： ZANG Zhen-le HU Ming-yu LI Xian-bi CHEN Kui-jun LIAO Peng XIAO Yue-hua HOU lei PEI Yanand LUO Ming Key Laboratory of biotechnology and Crop Quality Improvement Ministry of Agriculture/Biotechnology Research Center SouthwestUniversity Chongqing 400716 P.R.China

Beside as precursors of BRs biosynthesis, more and more evidences supported that phytosterols play an important role in plant growth and development. To investigate the effects of phytosterols on the fiber development of upland cotton （Gossypium hirsutum L.） and the molecular base of sterol regulating cotton fiber growth, a homologue of HYDRA1 was cloned from upland cotton （cv. Xuzhou 142） by screening cotton fiber EST database and contigging the candidate ESTs. The GhHYDRA1 encoded a polypeptide of 218 amino acid residues and the deduced amino acid sequences had high homology with the members of HYDRA1 in Populus trichocarpa, Solanum tuberosum, and Arabidopsis thaliana. Moreover, GhHYDRA1 had comparable transmembrane regions to AtHYDRA1 in sequence, length, order, and spacing, except for a C-terminal polylysine cluster. Quantitative real-time RT-PCR analysis revealed that the higher expression levels of GhHYDRA1 gene were detected in 6 to 12 DPA （days post anthesis） fibers, while the lower levels were observed in 0 DPA ovule （with fibers） and 16 to 18 DPA fibers. These results indicated that GhHYDRA1 is the homologue of HYDRA1 gene and plays a crucial role in fiber elongation. Furthermore, auxin and BL up-regulated the expression level of GhHYDRA1 while ABA and KT down-regulated the expression level of GhHYDRA1 in cotton ovule and fiber growth. The result suggested that phytosterols play a role in the interaction of plant hormones.

关键词： cotton fiber phytosterols brassinosteroids GhHYDRA1

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

上海大金山岛不同植被类型土壤细菌群落的变异

引用

植物生态学报 2024年第3期48卷 377-389页

作者：杨安娜李曾燕牟凌杨柏钰赛碧乐张立张增可王万胜杜运才由文辉阎恩荣华东师范大学生态与环境科学学院上海200241 上海市金山区海洋海塘管理所上海201508

揭示次生演替过程中土壤细菌群落对植被类型变化的响应格局,有助于深化对生态系统地上地下相互作用机制的理解。该研究以上海大金山岛处于演替前、中和后期的落叶灌丛、落叶阔叶林和常绿阔叶林为对象,通过测定土壤碳、氮、磷含量以及土... 详细信息

揭示次生演替过程中土壤细菌群落对植被类型变化的响应格局,有助于深化对生态系统地上地下相互作用机制的理解。该研究以上海大金山岛处于演替前、中和后期的落叶灌丛、落叶阔叶林和常绿阔叶林为对象,通过测定土壤碳、氮、磷含量以及土壤细菌群落特征,分析土壤细菌多样性、类群关系网络结构和标志性类群如何随植被演替而更替。结果发现:土壤养分含量在常绿阔叶林显著高于落叶阔叶林,但土壤细菌多样性在落叶阔叶林显著高于常绿阔叶林,土壤养分含量和细菌多样性在落叶灌丛处于中等水平。土壤细菌的相关性网络节点、密度和复杂性在落叶阔叶林最高,在落叶灌丛中等,在常绿阔叶林最低。落叶灌丛和落叶阔叶林的优势土壤细菌分别为根瘤菌目(Rhizobiales)和伯克氏菌目(Burkholderiales)等具有潜在固氮功能的类群,常绿阔叶林的优势土壤细菌为黄单胞菌目(Xanthomonadales)和嗜热芽菌目(Thermogemmatisporales)等具有潜在致病和抗病性功能的类群以及酸杆菌目(Acidobacteriales)等与纤维素降解相关的类群。该结果表明:海岛植被演替过程中,植物种类组成和土壤养分供给性的改变会极大地重塑土壤细菌多样性、群落组成、互作网络结构和标志类群。海岛常绿阔叶林显著更低的土壤细菌多样性、趋于松散简化的细菌网络结构以及具有潜在致病和抗病功能的标志类群的出现,说明了顶极群落地下部分对地上部分退化趋势的响应。

关键词：次生演替岛屿灌丛森林细菌多样性 16S rDNA

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

25CrMo4合金结构钢的力—磁效应

引用

哈尔滨工程大学学报 2019年第8期40卷 1524-1529页

作者：毕贞法孔乐上海应用技术大学轨道交通学院

为了实现磁记忆检测技术在列车轮对检测方面的应用,需要对轮对所用材料的力-磁效应进行研究。以25CrMo4合金结构钢为例,对其板状试件进行准静态拉伸,通过专用的磁记忆信号采集仪器记录板件在不同载荷下的磁记忆信号,提取各载荷下的信号... 详细信息

为了实现磁记忆检测技术在列车轮对检测方面的应用,需要对轮对所用材料的力-磁效应进行研究。以25CrMo4合金结构钢为例,对其板状试件进行准静态拉伸,通过专用的磁记忆信号采集仪器记录板件在不同载荷下的磁记忆信号,提取各载荷下的信号的常用信号特征,分析了其应力与磁记忆信号的关系。实验结果表明,随着载荷的增加,磁记忆信号随着实验试件的载荷增加而有较大影响。

关键词：高速列车 25CrMo4钢准静态拉伸金属磁记忆检测力-磁效应法向分量切向分量梯度

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

高吸收锗硅酸盐掺铋光纤及其增益性能研究

引用

中国激光 2024年第2期51卷 130-135页

作者：刘少坤何乐殷晓科褚应波戴能利李进延华中科技大学武汉光电国家研究中心湖北武汉430074

目前基于掺铒光纤放大器(EDFA)的光纤通信骨干网络仅能有效利用C+L波段(1524~1625 nm)。在E+S波段,锗硅酸盐掺铋光纤可进一步扩展放大器的增益带宽,具有重要研究价值,但其过长的使用长度严重制约了其应用。报道了一种高吸收锗硅酸盐掺... 详细信息

目前基于掺铒光纤放大器(EDFA)的光纤通信骨干网络仅能有效利用C+L波段(1524~1625 nm)。在E+S波段,锗硅酸盐掺铋光纤可进一步扩展放大器的增益带宽,具有重要研究价值,但其过长的使用长度严重制约了其应用。报道了一种高吸收锗硅酸盐掺铋光纤,其使用长度得到大大缩短,同时具有高增益。基于前向泵浦结构测试了掺铋光纤的增益性能,泵浦功率和波长分别为367 mW和1310 nm,输入信号总功率为-20 dBm。结果表明,50 m长的光纤在1414~1479 nm实现了大于20 dB的增益,65 m长的光纤的增益在1450 nm处达到最大(33 dB),单位长度增益系数达0.51 dB/m。研究结果证明了锗硅酸盐掺铋光纤在WDM光纤通信网络中的实际应用潜力。

关键词：光纤光学锗硅酸盐掺铋光纤高吸收 E+S波段放大

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

用于U波段高效放大的高锗掺铋光纤

引用

中国激光 2024年第6期51卷 189-194页

作者：刘少坤殷晓科何乐褚应波戴能利李进延华中科技大学武汉光电国家研究中心湖北武汉430074

掺铋(bi)光纤由于其超宽带近红外发光性能引起了广泛关注,然而实现U波段高效放大的高锗(Ge)掺铋光纤在国内依然尚未研制成功,这是因为在掺铋光纤中实现高掺锗是一项极具挑战的工艺难点,同时如何实现bi向Ge相关铋活性中心高效转化也是一... 详细信息

掺铋(bi)光纤由于其超宽带近红外发光性能引起了广泛关注,然而实现U波段高效放大的高锗(Ge)掺铋光纤在国内依然尚未研制成功,这是因为在掺铋光纤中实现高掺锗是一项极具挑战的工艺难点,同时如何实现bi向Ge相关铋活性中心高效转化也是一个难题。基于改进的化学气相沉积技术,制备了一种纤芯GeO2摩尔分数约为42%的高锗掺铋光纤。其吸收测试结果显示,在1650 nm处出现明显的Ge相关铋活性中心的吸收峰。通过单级放大系统表征了其放大性能,在1670 nm处实现了26.3 dB的最高增益,增益效率达0.165 dB/mW。

关键词：光纤光学高锗掺铋光纤改进的化学气相沉积 U波段放大

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：