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141.
张猛 《青年论坛》2006,(5):100-102
随着网络技术的广泛应用以及网络安全的日益重要,虚拟专用网VPN得到广泛应用。如何对VPN网络进行有效管理成为一个迫切需要解决的问题。本文从实际需求出发,提出了一个对VPN网络进行策略管理的模型,该模型效率较高,具有较大的现实意义。  相似文献   
142.
社会稳定历来就是执政者和普通百姓都十分关注的问题。我国正处于社会转型期,社会稳定问题理所当然备受关注。但是,如何维护社会稳定?如何创造出一种对社会稳定的测量方法,能够在社会将要失稳之前就超前预警和预控社会的政治局面?这无疑是一个既有现实意义,又有理论价值的重大课题。对此,采用系统动态分析的方法和社会指标技术,建立一套能够对社会稳定的程度进行计量的工具——社会稳定指标体系,对于国家各级政府完善社会预警机制,维护社会稳定会大有裨益。  相似文献   
143.
中国城市社区组织管理模式的构建与创新   总被引:1,自引:0,他引:1  
我国城市社区建设与管理工作已取得了很大成绩,各地也形成了各具特色的社区组织管理模式。但综观全国城市社区组织管理的现状,大多处于初级的经验型层面,存在着很多问题。因此,有必要从科学的组织管理理念出发,构建一种新型的城市社区组织管理模式,使城市社区组织管理逐步由行政管理体制向法制保障下的社区居民自治体制转变,并且随着社区建设的发展而不断完善。  相似文献   
144.
构建学习型政府是当代社会经济发展的客观要求.结构再造是构建学习型政府的基础,文化重塑是构建学习型政府的核心,机制创建是构建学习型政府的保障.  相似文献   
145.
《Science & justice》2021,61(6):669-677
In forensic identification, the use of foot dimensions to predict stature is a requisite. For Taiwanese male stature prediction, available information about stature estimation using foot dimensions is still lacking. Therefore, the primary purpose of this study was to establish Taiwanese adult male stature prediction models for various foot dimensions. A total of 2,072 male 3D foot models were collected and the subjects' ages ranged from 18 to 59 years old. Thirteen foot dimensions for each foot were utilized in this study. Bilateral differences were tested using paired t-tests. Stature predictions based on different foot dimensions were conducted using simple linear and stepwise regression methods. The results showed significant bilateral differences in the majority of the selected foot dimensions (p < 0.001). Foot length had the highest positive correlation with stature in the right and left foot. Using length-related dimensions generated better prediction accuracy (0.356 < R2 < 0.533, 4.193 < SEE < 4.928), whereas the worst accuracy was observed with angle-related dimensions (0.001 < R2 < 0.023; 6.072 < SEE < 6.137) when employing a single foot dimension to estimate Taiwanese male stature. Stepwise regression analysis results indicated that the coefficient of determination was improved to 0.590 and 0.593 by applying five and six foot parameters to predict stature, respectively. The findings of the present study suggest that these stature estimation equations can be applied to predict Taiwanese male stature in the forensic science field.  相似文献   
146.
目的尸体角膜随死后时间延长发生的形态学变化是规律性较好的指标,常用来判断死亡时间(postmortem interval,PMI)。本文尝试用机器视觉代替人的肉眼主观判断,收集尸体样本以建立通过人体角膜图像推断PMI的模型。方法收集实际案例建立包含505例人体死后角膜图像的数据库,PMI范围为0.24h(约死后14min)至492h(约死后20.5d),大致分为三类(依次为:0~<6h、6~<20h、20h及以上)或二类(0~<15h、15h及以上);使用由华盛顿大学陈天奇博士提出的Xgboost模型分别进行二分类与三分类分析;使用多种卷积神经网络模型分别进行分类和回归学习,并通过比较最终选择了由微软研究院提出的ResNet模型进行分析。结果Xgboost在三分类时预测准确率依次为71.8%、40.7%、65.7%,二分类时为90%、48.5%。ResNet分类模型中,精准率、召回率在三分类时分别依次为:81%、75%,30%、50%,61%、71%,二分类时为:70%、92%,76%、38%。ResNet回归模型中,比较整个模型的预测结果,0~6h内的预测值与真实值较为接近,均值误差为0.5616,均方误差为0.5873,6h之后开始出现较大误差。结论分类和回归模型都在0~6h之内得到了很好的结果,说明在此时间段内,角膜图像噪声较低,可预测性强。  相似文献   
147.
As an alternative to sprawling development, smart growth combines proximity to work, proximity to shopping and other destinations, neighborhood housing mix, shared and paid parking, complete street designs, and proximity to public transit. This article uses a stated-choice experiment to determine residents' attitudes toward these various aspects of smart growth in the Salt Lake region of Utah. Utah is a conservative state, where attitudes toward auto-oriented suburbia may be more positive than in other parts of the United States. So, one might wonder whether changing national attitudes toward smart growth, documented in several surveys, apply to residents of the Salt Lake region. In this stated-choice experiment, respondents were asked to choose between pairs of housing scenarios with different attributes and different prices. Mixed logit (random parameters logit) was used to relate individuals' choices to attributes, prices, and sociodemographic characteristics of respondents. The results show that, generally, respondents have positive attitudes toward most aspects of smart growth but still express preferences for single-family neighborhoods with free parking in their own driveways or garages. Different life cycle cohorts have different preferences. Proximity to work is more important for childless young adults. Young families with children place higher value on living in a neighborhood with only single-family homes and transit access. Retired empty nesters favor a mix of housing types over single-family housing on one-acre-plus lots. The results suggest that while residents of the Salt Lake region like suburban neighborhoods with primarily single-family houses, they would also like to have improved accessibility to amenities in the suburbs.  相似文献   
148.
This article explores the role that ground troops play in aerial campaigns. Specifically, it intends to explain how ground troops affect the duration of aerial bombing campaigns. It distinguishes between the effect of ground troops on the duration of aerial campaigns that are selective and on those that are more general and less discriminate (using newly coded data on aerial strategies). The effect of ground troops may vary depending on how air power is being used. Ground troops may increase the duration of aerial campaigns in cases in which selective strategies are used during the aerial bombing campaign. In these cases, states lose the possibility of quick, “clean” victories once ground troops are introduced. In the cases of the less-discriminate bombing campaigns, the effect of ground troops is the opposite: They shorten the duration of the bombing campaign, possibly through the increased effectiveness of a combined arms approach.  相似文献   
149.
Drunk driving is a serious threat to public safety. All available and appropriate tools for curbing this threat should be employed to their full extent. The handheld pre‐arrest breath test instrument (PBT) is one tool for identifying the alcohol‐impaired driver and enforcing drunk driving legislation. A set of data was evaluated (n = 1779) where the PBT instrument was employed in drunk driving arrests to develop a multivariate predictive model. When maintained and operated by trained personnel, the PBT provides a reasonable estimate of the evidential test result within the relevant forensic range (95% prediction interval:  ± 0.003 g/210 L). ROC analysis shows that a multivariate model for PBT prediction of the evidentiary alcohol concentration above versus below the legal limit of 0.08 g/210 L has excellent performance with an AUC of 0.96. These results would be of value in evidential hearings seeking to admit the PBT results in drunk driving trials.  相似文献   
150.
The Covenant of Mayors (CM) is the mainstream European movement involving local authorities who voluntarily commit to increase energy efficiency and the use of renewable energy sources within their territories with the aim of reducing CO2 emissions and meet the European Union objectives by 2020. One country that has a greater number of signatories of this agreement is Spain. This article analyzes which factors influence the decision of Spanish local authorities to join the ever‐growing movement. An empirical model is formulated to describe the behavior of Spanish local governments, this being a binary choice model which is a function of various political, economic, and technical factors. Among the prominent factors that influence this decision are population, availability of renewable energy, fiscal and environmental stress, citizens’ political preference, the contagion effect of neighboring municipalities, the existence of covenant coordinators, and finally, economic motivations.  相似文献   
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