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基于K-means聚类和改进蚁群算法的跨境电商仓储选址优化研究
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作者 邱国斌 易玉涛 《物流研究》 2026年第1期84-92,共9页
为解决传统选址方法无法动态适配跨境场景的问题,本文针对跨境电商仓储选址的复杂性与灵活性,结合跨境电商特有的国际物流成本、关税政策、区域市场需求、汇率波动等核心要素,构建基于K-means聚类和改进蚁群算法的跨境电商仓储选址模型... 为解决传统选址方法无法动态适配跨境场景的问题,本文针对跨境电商仓储选址的复杂性与灵活性,结合跨境电商特有的国际物流成本、关税政策、区域市场需求、汇率波动等核心要素,构建基于K-means聚类和改进蚁群算法的跨境电商仓储选址模型。本研究通过在多约束条件下的MATLAB软件仿真模拟,将现有选址与优化后选址进行比较。研究表明,该模型能够有效优化跨境电商仓储选址方案,为企业在全球供应链布局中提供科学决策支持。 展开更多
关键词 跨境电商 仓储选址 改进蚁群算法 MATLAB仿真 K-meANS聚类
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基于MC-UVE-GA和GA-MC-UVE算法联用构建电子烟烟液中烟碱含量快检的近红外模型
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作者 陈丹 邓惠敏 +7 位作者 龙杰 李长昱 李郸 孙浩巍 张轲 李明 王春琼 陈黎 《分析试验室》 北大核心 2025年第11期1617-1623,共7页
为提高电子烟烟液中烟碱含量傅里叶变换近红外(FT-NIR)预测模型的准确性,将光谱数据采用标准正态变量变换(SNV)算法预处理后,分别采用蒙特卡洛无信息变量消除法(MC-UVE)、遗传算法(GA)以及2种算法联用(MC-UVE-GA和GA-MC-UVE)选择波数变... 为提高电子烟烟液中烟碱含量傅里叶变换近红外(FT-NIR)预测模型的准确性,将光谱数据采用标准正态变量变换(SNV)算法预处理后,分别采用蒙特卡洛无信息变量消除法(MC-UVE)、遗传算法(GA)以及2种算法联用(MC-UVE-GA和GA-MC-UVE)选择波数变量,并基于筛选后的变量建立了偏最小二乘(PLS)回归模型。对比不同算法的预测效果,2种算法联用后所建模型的预测均方根误差(RMSEP)更低,且校正均方根误差(RMSEC)更接近于RMSEP,过拟合风险小,最优的GA和MC-UVE联用偏最小二乘(GA-MC-UVE-PLS)回归模型所用波数变量为50个,仅占全谱的3.2%,其交叉验证决定系数(RCV2)从全谱时的0.991提高到了0.994,交叉验证均方根误差(RMSECV)和RMSEP从全谱时的0.810和0.836分别降低至0.690和0.698。通过MC-UVE和GA算法的联用,能在初选变量基础上再精选出更少、更有效的变量,有效提高模型的预测精度和泛化能力。 展开更多
关键词 近红外光谱 蒙特卡洛无信息变量消除法 遗传算法 电子烟烟液 烟碱
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E-MS算法的收敛性
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作者 徐平峰 陈婷 尚来旭 《吉林大学学报(理学版)》 CAS 北大核心 2019年第5期1127-1130,共4页
考虑E-MS算法的收敛性.首先,给出观测广义信息准则(GIC)最小值点的必要条件;其次,在模型空间有限性、参数空间紧性、Q函数连续性的条件下,证明E-MS算法产生序列的极限点满足观测GIC最小值点的必要性,是对E-MS算法全局收敛性的补充;再次... 考虑E-MS算法的收敛性.首先,给出观测广义信息准则(GIC)最小值点的必要条件;其次,在模型空间有限性、参数空间紧性、Q函数连续性的条件下,证明E-MS算法产生序列的极限点满足观测GIC最小值点的必要性,是对E-MS算法全局收敛性的补充;再次,给出满足该必要条件但不满足全局收敛条件高斯图模型的一个实例;最后,证明E-MS算法的全局收敛性. 展开更多
关键词 缺失数据 模型选择 观测GIC e-ms算法
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Systematic calibration of a 2-m Ring Solar Telescope based on local interferometry and model comparison
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作者 Renai Liu Jinpeng Li +2 位作者 Zuozifei Song Changyu Zeng Yichun Dai 《Astronomical Techniques and Instruments》 2025年第3期175-185,共11页
To address the installation challenges of a 2-m ring Gregorian telescope system,and similar optical systems with a small width-to-radius ratio,we propose a detection method combining local interferometry with a compar... To address the installation challenges of a 2-m ring Gregorian telescope system,and similar optical systems with a small width-to-radius ratio,we propose a detection method combining local interferometry with a comparison model.This method enhances the precision of system calibration by establishing a dataset that delineates the relationship between secondary mirror misalignment and wavefront aberration,subsequently inferring the misalignment from interferometric detection results during the calibration process.For the 2-m ring telescope,we develop a detection model using five local sub-apertures,enabling a root-mean-square detection accuracy of 0:0225λ(λ=632:8 nm)for full-aperture wavefront aberration.The calibration results for the 2-m Ring Solar Telescope system indicate that the root-mean-square value of sub-aperture wavefront aberration reaches 0.104λ,and the root-mean-square value of spliced full-aperture measurement yields reaches 0.112λ.This method offers a novel approach for calibrating small width-toradius ratio telescope systems and can be applied to the calibration of other irregular-aperture optical systems. 展开更多
关键词 Local aperture Model comparison 2-m Ring Solar Telescope System calibration Splicing algorithm
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基于E-MS算法的含缺失数据图模型选择的模拟研究
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作者 孙聚波 徐平峰 《佳木斯大学学报(自然科学版)》 CAS 2015年第5期741-743,共3页
图模型是处理高维数据的有力工具,其中图模型的选择是统计推断的重要方面.利用E-MS算法进行缺失数据的图模型选择.E-MS算法是基于EM迭代思想的,把模型下的参数和模型选择参数统一为新的参数,这样模型选择就成为E-M迭代过程的一部分.最... 图模型是处理高维数据的有力工具,其中图模型的选择是统计推断的重要方面.利用E-MS算法进行缺失数据的图模型选择.E-MS算法是基于EM迭代思想的,把模型下的参数和模型选择参数统一为新的参数,这样模型选择就成为E-M迭代过程的一部分.最后给出了3,4,5变量情形下的模拟研究. 展开更多
关键词 列联表 图模型 模型选择 e-ms算法
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DM2患者血清CysC、β_2-m及sE-selectin检测的临床意义 被引量:2
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作者 陈斌 陈峻 胡必成 《放射免疫学杂志》 CAS 2013年第3期360-361,共2页
本文对75例2型糖尿病(DM2)患者及50例健康对照者血液中的血清胱抑素C(CysC)、β2-微球蛋白(β2-m)及可溶性E选择素(sE—selectin)的浓度进行了测定和分析,现报告如下。
关键词 Se-SeLeCTIN 血清CYSC 临床意义 Β2-m 患者 DM2 可溶性e选择素 β2-微球蛋白
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一种基于正态分布交叉的ε-MOEA 被引量:33
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作者 张敏 罗文坚 王煦法 《软件学报》 EI CSCD 北大核心 2009年第2期305-314,共10页
实数编码的多目标进化算法常使用模拟二进制交叉(simulated binary crossover,称SBX)算子.通过对SBX以及进化策略中变异算子进行对比分析,并引入进化策略中的离散重组算子,提出了一种正态分布交叉(normal distribution crossover,称NDX... 实数编码的多目标进化算法常使用模拟二进制交叉(simulated binary crossover,称SBX)算子.通过对SBX以及进化策略中变异算子进行对比分析,并引入进化策略中的离散重组算子,提出了一种正态分布交叉(normal distribution crossover,称NDX)算子.首先在一维搜索空间实例中对NDX与SBX算子进行比较和分析,然后将NDX算子应用于Deb等人提出的稳态多目标进化算法ε-MOEA(ε-dominance based multiobjective evolutionary algorithm)中.采用NDX算子的ε-MOEA(记为ε-MOEA/NDX)算法在多目标优化标准测试集ZDT和DTLZ的10个函数上进行了实验比较.实验结果和分析表明,采用NDX的ε-MOEA所求得的Pareto最优解集质量明显优于经典算法ε-MOEA/SBX和NSGA-Ⅱ. 展开更多
关键词 进化多目标优化 ε-mOeA(ε-dominance BASeD MULTIOBJeCTIVe eVOLUTIONARY algorithm) 正态分布交叉 模拟二进制交叉
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细菌觅食算法与K-means结合的Web用户会话聚类 被引量:2
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作者 凌海峰 王浩 《计算机工程与应用》 CSCD 2012年第36期121-124,176,共5页
Web用户会话聚类是电子商务领域的NP-难问题,目的是发现相似的用户访问行为模式。该问题难度在于对大规模的Web会话进行聚类,且每个会话都表示为高维向量。提出一种细菌觅食算法和K-means相结合的优化算法,用知名的数据集测试其有效性。... Web用户会话聚类是电子商务领域的NP-难问题,目的是发现相似的用户访问行为模式。该问题难度在于对大规模的Web会话进行聚类,且每个会话都表示为高维向量。提出一种细菌觅食算法和K-means相结合的优化算法,用知名的数据集测试其有效性。对Web会话进行聚类,与流行的聚类算法进行比较,实验结果显示该算法高效且性能更优。 展开更多
关键词 WeB使用挖掘 细菌觅食优化 K-meANS算法 会话聚类 电子商务
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E-mail的安全问题与保护措施 被引量:1
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作者 张震 《航空计算技术》 2000年第2期42-44,48,共4页
全面分析了E -mail的安全问题 ,并提出了应该采用的有效方法 ,以保护E -mail系统能安全运行。
关键词 电子邮件 安全性 防火墙 加密算法 e-mail炸弹 PGP
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E-mail信息加密技术与算法分析
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作者 张连永 刘永强 +1 位作者 崔淑明 朱虹 《首都师范大学学报(自然科学版)》 2007年第2期19-22,共4页
分析了E-mail信息网络传递的现状,使用E-mail存在的不安全隐患.提出了一种有效地保护E-mail信息安全传递的加密技术和算法.
关键词 e-mAIL 软件 算法
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E-mail的安全问题与保护措施
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作者 张震 李竹林 刘兴平 《微机发展》 2000年第5期79-80,F003,共3页
本文全面分析了E -mail安全问题 ,并提出了应该采用的有效方法 ,以保护E -mail系统能安全运行。
关键词 电子邮件 安全性 防火墙 加密算法 PGP
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改进的k-means算法在电子商务目标客户细分中的应用研究 被引量:1
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作者 夏同胜 黄雨辰 《吉林工程技术师范学院学报》 2015年第3期58-60,共3页
本文针对k-means算法的不足,对其进行了改进,并将改进后的k-means算法应用于水果类电子商务网站的客户数据分析,算法显著地提高了聚类的质量,从而提高了电子商务企业开展营销活动的有效性和针对性。
关键词 电子商务 客户细分 K-meANS算法
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A study on the dynamic tie points ASI algorithm in the Arctic Ocean 被引量:9
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作者 HAO Guanghua SU Jie 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第11期126-135,共10页
Sea ice concentration is an important parameter for polar sea ice monitoring. Based on 89 GHz AMSR-E (Advanced Microwave Scanning Radiometer for Earth Observing System) data, a gridded high-resolution passive microw... Sea ice concentration is an important parameter for polar sea ice monitoring. Based on 89 GHz AMSR-E (Advanced Microwave Scanning Radiometer for Earth Observing System) data, a gridded high-resolution passive microwave sea ice concentration product can be obtained using the ASI (the Arctic Radiation And Turbulence Interaction Study (ARTIST) Sea Ice) retrieval algorithm. Instead of using fixed-point values, we developed ASi algorithm based on daily changed tie points, called as the dynamic tie point ASI algorithm in this study. Here the tie points are expressed as the brightness temperature polarization difference of open water and 100% sea ice. In 2010, the yearly-averaged tie points of open water and sea ice in Arctic are estimated to be 50.8 K and 7.8 K, respectively. It is confirmed that the sea ice concentrations retrieved by the dynamic tie point ASI algorithm can increase (decrease) the sea ice concentrations in low-value (high-value) areas. This improved the sea ice concentrations by present retrieval algorithm from microwave data to some extent. Comparing with the products using fixed tie points, the sea ice concentrations retrieved from AMSR-E data by using the dynamic tie point ASI algorithm are closer to those obtained from MODIS (Moderate-resolution Imaging Spectroradiometer) data. In 40 selected cloud-free sample regions, 95% of our results have smaller mean differences and 75% of our results have lower root mean square (RMS) differences compare with those by the fixed tie points. 展开更多
关键词 dynamic tie points ASI algorithm sea ice concentration AMSR-e MODIS
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A modified Gillespie algorithm for E.coli gene regulation systems
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作者 罗若愚 《生物物理学报》 CAS CSCD 北大核心 2009年第S1期10-10,共1页
The dynamics of complex gene regulation systems can be simulated by the Gillespie algorithm. The classic Gillespie algorithm is appropriate to simulate a stochastic
关键词 COLI A modified Gillespie algorithm for e.coli gene regulation systems GeNe
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A study of multiyear ice concentration retrieval algorithms using AMSR-E data 被引量:3
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作者 HAO Guanghua SU Jie 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第9期102-109,共8页
In recent years, the rapid decline of Arctic sea ice area (SIA) and sea ice extent (SIE), especially for the multiyear (MY) ice, has led to significant effect on climate change. The accurate retrieval of MY ice ... In recent years, the rapid decline of Arctic sea ice area (SIA) and sea ice extent (SIE), especially for the multiyear (MY) ice, has led to significant effect on climate change. The accurate retrieval of MY ice concentration retrieval is very important and challenging to understand the ongoing changes. Three MY ice concentration retrieval algorithms were systematically evaluated. A similar total ice concentration was yielded by these algorithms, while the retrieved MY sea ice concentrations differs from each other. The MY SIA derived from NASA TEAM algorithm is relatively stable. Other two algorithms created seasonal fluctuations of MY SIA, particularly in autumn and winter. In this paper, we proposed an ice concentration retrieval algorithm, which developed the NASA TEAM algorithm by adding to use AMSR-E 6.9 GHz brightness temperature data and sea ice concentration using 89.0 GHz data. Comparison with the reference MY SIA from reference MY ice, indicates that the mean difference and root mean square (rms) difference of MY SIA derived from the algorithm of this study are 0.65×10^6 km^2 and 0.69×10^6 km^2 during January to March, -0.06×10^6 km^2 and 0.14×10^6 km^2during September to December respectively. Comparison with MY SIE obtained from weekly ice age data provided by University of Colorado show that, the mean difference and rms difference are 0.69×10^6 km^2 and 0.84×10^6 km^2, respectively. The developed algorithm proposed in this study has smaller difference compared with the reference MY ice and MY SIE from ice age data than the Wang's, Lomax' and NASA TEAM algorithms. 展开更多
关键词 multiyear ice concentration retrieval algorithms AMSR-e data
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Diagnosis related group grouping study of senile cataract patients based on E-CHAID algorithm 被引量:9
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作者 AiJing Luo Wei-Fu Chang +6 位作者 Zi-Rui Xin Hao Ling Jun-Jie Li Ping-Ping Dai Xuan-Tong Deng Lei Zhang Shao-Gang Li 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2018年第2期308-313,共6页
AIM: To figure out the contributed factors of the hospitalization expenses of senile cataract patients(HECP) and build up an area-specified senile cataract diagnosis related group(DRG) of Shanghai thereby formula... AIM: To figure out the contributed factors of the hospitalization expenses of senile cataract patients(HECP) and build up an area-specified senile cataract diagnosis related group(DRG) of Shanghai thereby formulating the reference range of HECP and providing scientific basis for the fair use and supervision of the health care insurance fund.METHODS: The data was collected from the first page of the medical records of 22 097 hospitalized patients from tertiary hospitals in Shanghai from 2010 to 2012 whose major diagnosis were senile cataract. Firstly, we analyzed the influence factors of HECP using univariate and multivariate analysis. DRG grouping was conducted according to the exhaustive Chi-squared automatic interaction detector(E-CHAID) model, using HECP as target variable. Finally we evaluated the grouping results using non-parametric test such as Kruskal-Wallis H test, RIV, CV, etc.RESULTS: The 6 DRGs were established as well as criterion of HECP, using age, sex, type of surgery and whether complications/comorbidities occurred as the key variables of classification node of senile cataract cases.CONCLUSION: The grouping of senile cataract cases based on E-CHAID algorithm is reasonable. And the criterion of HECP based on DRG can provide a feasible way of management in the fair use and supervision of medical insurance fund. 展开更多
关键词 diagnosis related group senile cataract hospitalization expenses e-CHAID algorithm
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Scheduling Algorithm for Multimedia Services in IEEE 802.16e OFDM System
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作者 董国军 戴居丰 《Transactions of Tianjin University》 EI CAS 2008年第1期31-36,共6页
Based on five scheduling types and their QoS requirements defined in IEEE 802.16e specification, this paper proposes a new scheduring algorithm for non-real-time or real-time multimedia services. Taking the performanc... Based on five scheduling types and their QoS requirements defined in IEEE 802.16e specification, this paper proposes a new scheduring algorithm for non-real-time or real-time multimedia services. Taking the performances of efficiency, fairness and complexity into consideration, the proposed algorithm enhances the efficiency of air interface resource at the expense of the short-time unfairness, but ensures the long-time fairness. Moreover, the proposed algorithm introduces an efficient QoS assurance mechanism, which implements the functions of congestion control, queuing management and traffic management. The simulation results based on a simplified traffic model show that the proposed algorithm guarantees better performances of efficiency and fairness than conventional algorithms, without increasing the algorithm complexity. Especially on the occasion of heavy-traffic requirement, the performance of efficiency and fairness can be improved by 50% at most. 展开更多
关键词 Ieee 802.16e scheduling algorithm SUBCHANNeL efficiency FAIRNeSS COMPLeXITY
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A Multi-stage Heuristic Algorithm for Matching Problem in the Modified Miniload Automated Storage and Retrieval System of E-commerce 被引量:2
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作者 WANG Wenrui WU Yaohua WU Yingying 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第3期641-648,共8页
E-commerce, as an emerging marketing mode, has attracted more and more attention and gradually changed the way of our life. However, the existing layout of distribution centers can't fulfill the storage and picking d... E-commerce, as an emerging marketing mode, has attracted more and more attention and gradually changed the way of our life. However, the existing layout of distribution centers can't fulfill the storage and picking demands of e-commerce sufficiently. In this paper, a modified miniload automated storage/retrieval system is designed to fit these new characteristics of e-commerce in logistics. Meanwhile, a matching problem, concerning with the improvement of picking efficiency in new system, is studied in this paper. The problem is how to reduce the travelling distance of totes between aisles and picking stations. A multi-stage heuristic algorithm is proposed based on statement and model of this problem. The main idea of this algorithm is, with some heuristic strategies based on similarity coefficients, minimizing the transportations of items which can not arrive in the destination picking stations just through direct conveyors. The experimental results based on the cases generated by computers show that the average reduced rate of indirect transport times can reach 14.36% with the application of multi-stage heuristic algorithm. For the cases from a real e-commerce distribution center, the order processing time can be reduced from 11.20 h to 10.06 h with the help of the modified system and the proposed algorithm. In summary, this research proposed a modified system and a multi-stage heuristic algorithm that can reduce the travelling distance of totes effectively and improve the whole performance of e-commerce distribution center. 展开更多
关键词 e-commerce modified miniload automated storage/retrieval system matching problem multi-stage heuristic algorithm
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Logarithmic Growth Algorithm of Sleep Mode of Broadband Mobile Access Terminal
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作者 唐朝伟 邵艳清 唐晖 《Transactions of Tianjin University》 EI CAS 2010年第6期452-456,共5页
The sleep mode which works upon low arrival traffic is introduced in IEEE802.16e standard to reduce the power consumption of the mobile access terminal. Due to the rapid growth in the sleep interval in the exponential... The sleep mode which works upon low arrival traffic is introduced in IEEE802.16e standard to reduce the power consumption of the mobile access terminal. Due to the rapid growth in the sleep interval in the exponential growth algorithm prescribed in IEEE802.16e, the power saving efficiency of the mobile access terminal is limited and the average delay time of receiving data frames is prolonged when the arrival rate of data frames is low. To obtain lower power consumption and shorter average delay time, the l... 展开更多
关键词 Ieee802.16e sleep mode mobile access terminal average power consumption average delay time logarithmic growth algorithm
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e-mail的安全性研究
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作者 尚小林 《西安邮电学院学报》 1999年第2期16-19,共4页
全面研究了e-mail的工作原理和e-mail的安全性问题,提出了应该采取的安全性防范措施。
关键词 安全性 防火墙 加密算法 电子邮件 INTeRNeT
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