多级防火墙技术研究与应用探讨

在计算机信息技术和互联网飞速发展的今天,互联网在人类的生活、工作、学习中占据着重要地位。然而计算机网络安全是其与之俱来不可避免的问题。本文将基于多级防火墙技术,分析当前计算机网络中存在的安全隐患,针对这些实际问题探讨如何有效应用多级防火墙技术,实现对计算机网络安全的维护。     

基于模型修正技术的模拟集成电路几何规划优化方法

为了兼顾模拟集成电路设计优化的求解精度和计算效率,提出一种基于正项式模型修正技术的几何规划优化方法.首先将模拟集成电路的设计目标与约束简化为正项式模型,然后在采用几何规划方法迭代优化的过程中利用晶体管级SPICE仿真不断修正这一正项式模型.实例表明,与传统基于公式的优化方法和基于仿真的优化方法相比,该方法能够在尽量保证计算效率和全局最优解的前提下使优化精度满足晶体管级SPICE仿真的要求.     

改进的门单元多输入跳变电流源模型

电压信号的非线性问题和多输入跳变现象给时序分析带来了严重挑战.为更好地解决此问题,文中设计电路对门单元输入端和内部节点间的密勒电容进行了验证,从器件结构上分析了其来源,并通过引入该电容改进了已有多输入跳变电流源模型,以获得更高的模型精度;同时将二输入门单元模型扩展到多输入门单元,并详述了建模方法.多种门单元上的数值实验结果表明,与已有模型相比,在可接受的时间开销内,文中模型能够显著地提高门单元时延和输出波形的仿真精度.     

pH传感器温度补偿模型研究

水质pH值在线监测对提高水产品健康养殖至关重要,本文将无线传感器网络与pH值传感器相集成,设计了pH值监测的无线传感器网络系统。为克服pH值测量过程中温度对测量结果的影响,提出了一种pH传感器温度补偿模型,该模型通过pH传感器和PT100铂电阻温度传感器分别测量溶液的pH值和温度,利用最小二乘法对pH值和电压进行线性分析,建立pH传感器的温度补偿模型。实验结果表明,该补偿模型测量精度高,能够实现较精确的pH值在线监测。     

“三位一体”数字校园的设计与实现

介绍了集＂日常管理＂、＂水平评估＂、＂决策规划＂三位于一体的数字校园设计方案。通过规范基础数据,采用ESB整合各业务子系统,解决＂信息孤岛＂问题,并为状态数据采集提供便利。利用BI软件进行数据挖据,为管理者进行科学规划和决策提供数据支持。系统采用单点登录,个性化的门户展现满足了各类用户对资源和服务的需求。     

Dump技术在Solaris系统恢复中的应用研究

对Solaris操作系统核心部分、数据文件部分的备份和恢复方法进行了描述,论述了Dump技术在Solaris系统恢复中的应用.分析表明,Dump技术是Solaris操作系统恢复技术中最为快捷有效的方法之一,它可以使系统快速地恢复正常,保证系统的稳定运行.     

Differential Evolution Algorithm Based Self-adaptive Control Strategy for Fed-batch Cultivation of Yeast

In the fed-batch cultivation of Saccharomyces cerevisiae, excessive glucose addition leads to increased ethanol accumulation, which will reduce the efficiency of glucose utilization and inhibit product synthesis. Insufficient glucose addition limits cell growth. To properly regulate glucose feed, a different evolution algorithm based on self-adaptive control strategy was proposed, consisting of three modules (PID, system identification and parameter optimization). Performance of the proposed and conventional PID controllers was validated and compared in simulated and experimental cultivations. In the simulation, cultivation with the self-adaptive control strategy had a more stable glucose feed rate and concentration, more stable ethanol concentration around the set-point (1.0 g•L^-1), and final biomass concentration of 34.5 g-DCW•L^-1, 29.2% higher than that with a conventional PID control strategy. In the experiment, the cultivation with the self-adaptive control strategy also had more stable glucose and ethanol concentrations, as well as a final biomass concentration that was 37.4% higher than that using the conventional strategy.     

Evaluating Visual Properties via Robust HodgeRank

International Journal of Computer Vision - Nowadays, how to effectively evaluate visual properties has become a popular topic for fine-grained visual comprehension. In this paper we study the...     

Sensitive attribute privacy preservation of trajectory data publishing based on l-diversity

Distributed and Parallel Databases - The widely application of positioning technology has made collecting the movement of people feasible for knowledge-based decision. Data in its original form...     

Research on the Effects of Institutional Liquidation Strategies on the Market Based on Multi-agent Model

Based on the multi-agent model, an artificial stock market with four types of traders is constructed. On this basis, this paper focuses on comparing the effects of liquidation behavior on market liquidity, volatility, price discovery efficiency and long memory of absolute returns when the institutional trader adopts equal-order strategy, Volume Weighted Average Price (VWAP) strategy and Implementation Shortfall (IS) strategy respectively. The results show the following: (1) the artificial stock market based on multi-agent model can reproduce the stylized facts of real stock market well; (2) among these three algorithmic trading strategies, IS strategy causes the longest liquidation time and the lowest liquidation cost; (3) the liquidation behavior of institutional trader will significantly reduce market liquidity, price discovery efficiency and long memory of absolute returns, and increase market volatility; (4) in comparison, IS strategy has the least impact on market liquidity, volatility and price discovery efficiency, while VWAP strategy has the least impact on long memory of absolute returns.