构建网络安全防护体系   总被引：1，自引：0，他引：1  

侯立志 《承德职业学院学报》2004,9(4):74-76

随着计算机技术和通信技术的发展,计算机网络将日益成为工业、农业和国防等方面的重要信息交换手段,渗透到社会生活的各个领域.网络安全问题日益突出,为了提高网络的整体安全水平必须全方位的构建网络安全防护体系,本文介绍网络安全防护体系的构建过程,并描述网络安全防护体系结构.  相似文献   

A color image segmentation method as used in the study of ancient monument decay     

Rossella Cossu  Laura Chiappini 《Journal of Cultural Heritage》2004,5(4):385-391

In the cultural heritage area, it is of fundamental importance to characterize and classify the conservation state of the materials constituting ancient monuments, in order to study and monitor their decay. Generally, the decay diagnosis is provided by “naked eye” analysis done by expert scientists “walking around” the artifact and recording the conservation state of each individual element they observe. In this paper, a color image segmentation approach, based on histogram threshold and edge detection techniques is presented, to extract degradation regions, characterized by holes or cavities, from color images of stone-materials. The goal is to provide an aid to the decay diagnosis by segmenting degraded regions from color images, computing quantitative data, such as the area and perimeter of the extracted zones, and processing qualitative information, such as various levels of depth detected into the same zones. Since color is a powerful tool in the distinction between objects, a segmentation technique based on color, instead of intensity only, has been used to provide a clearer discrimination between regions. The study case concerns the impressive remains of the Roman Theatre in the city of Aosta (Italy). In particular, we have processed and analyzed some color images of the theatre puddingstones, acquired by a camera.  相似文献   

金属焊接质量的红外成像检测     

王景中  徐小青 《上海海事大学学报》2001,22(3):214-216

介绍一种基于红外成像技术的金属焊接质量的无损检测方法.首先介绍了检测的基本原理和检测装置,然后详细给出了以边缘检测为基础的缺陷检测方法及检测结果.最后通过比较说明,利用红外成像技术对金属焊接质量进行无损检测是一种很有效的方法.  相似文献   

基于双目点云的三维物体检测准确性分析     

刘王超  娄鑫 《中国科学院大学学报》2022,39(5):677-683

双目相机虽然能通过算法生成密集的深度数据,但其在精度上与激光雷达生成的深度数据有着较大的差距,特别是在纹理不明显的区域。针对这种现象,尝试使用激光雷达的精确点云来排除由双目相机产生的pseudo-LiDAR数据中与之差别较大的部分点,然后将优化后的pseudo-LiDAR用以进行三维物体检测。实验结果显示,将pseudo-LiDAR数据中的不准确点（坏点）排除,有助于提高检测准确率,最多可提高21.02%。因此,如何不依赖激光雷达数据来排除pseudo-LiDAR点云中的坏点是进一步提高双目相机系统检测准确率的关键。  相似文献   

A Framework for Policies and Practices to Improve Test Security Programs: Prevention,Detection, Investigation,and Resolution (PDIR)          下载免费PDF全文

Steve Ferrara 《Educational Measurement》2017,36(3):5-23

Test security is not an end in itself; it is important because we want to be able to make valid interpretations from test scores. In this article, I propose a framework for comprehensive test security systems: prevention, detection, investigation, and resolution. The article discusses threats to test security, roles and responsibilities, rigorous training for everyone involved in testing, and an evaluation of current practices in test security. I call on everyone responsible for testing programs—the Association of Test Publishers, Council of Chief State School Officers, National Council on Measurement in Education, U.S. Department of Education, and state assessment program managers, their vendors, and the research community—to collaborate on guidelines and practices for security violation prevention, detection, investigation, and resolution.  相似文献   

The cumulative and residual fatigue response associated with soccer-specific activity performed on different playing surfaces     

Richard Michael Page  Ben Langley  Mitchell James Finlay  Matt Greig  Christopher Brogden 《Journal of sports sciences》2020,38(5):568-575

ABSTRACT

This study aimed to assess the effect of playing surface (Natural [NT] and Artificial [AT] Turf) on the fatigue response to a soccer-specific exercise protocol (SSEP). Eighteen male soccer players completed the SSEP on NT and AT with pre-, post-, and 48 h post-assessments of eccentric knee flexor (eccKF) and concentric knee extensor peak torque (PT), peak countermovement (CMJ) and squat jump (SJ) height, and Nordic hamstring break angle. No significant main effects for surface or any surface and time interactions were observed for any of the outcome measures, except for eccKF PT recorded at 3.14 rad·s^-1, which was significantly lower 48 h post-trial in the AT condition (AT = 146.3 ± 20.4 Nm; NT = 158.8 ± 24.7 Nm). Main effects for time were observed between pre- and post-trial measures for eccKF PT at all angular velocities, Nordic break angle, CMJ and SJ height. Nordic break angle, and both CMJ and SJ height were significantly impaired 48 h post-trial when compared to pre-trial. The findings of the current study suggest surface dependent changes in eccKF PT which may have implications for recovery and subsequent performance after competition on AT.  相似文献   

低重复率稿件中的学术不端行为检测与防范     

吴昔昔  贾建敏  吴健敏  王小同 《编辑学报》2016,28(3):266-269

重复率低却存在抄袭的稿件,其原因可能为单一的检测系统存在漏洞,新发表的论文上传数据库存在时间差,作者对稿件的有意识“修饰”,以及网络时代造假手段多样化.为此,文中提出以下措施:使用多种数据库进行文字检测,从查重报告中发现问题,建立有效的审稿专家数据库、网站教育和警示,充分利用网络资源,加快稿件处理进程,增强编辑的责任意识等,以利于更好地防范学术不端行为.  相似文献   

A learning-based method to detect and segment text from scene images     

JIANG Ren-jie QI Fei-hu XU Li WU Guo-rong ZHU Kai-hua 《浙江大学学报(A卷英文版)》2007,8(4):568-574

This paper proposes a learning-based method for text detection and text segmentation in natural scene images. First, the input image is decomposed into multiple connected-components (CCs) by Niblack clustering algorithm. Then all the CCs including text CCs and non-text CCs are verified on their text features by a 2-stage classification module, where most non-text CCs are discarded by an attentional cascade classifier and remaining CCs are further verified by an SVM. All the accepted CCs are output to result in text only binary image. Experiments with many images in different scenes showed satisfactory performance of our proposed method.  相似文献   

Predictive value of ventilatory inflection points determined under field conditions     

Christian Heyde  Hubert Mahler  Kai Roecker  Albert Gollhofer 《Journal of sports sciences》2016,34(9):787-793

The aim of this study was to evaluate the predictive potential provided by two ventilatory inflection points (VIP₁ and VIP₂) examined in field without using gas analysis systems and uncomfortable facemasks. A calibrated respiratory inductance plethysmograph (RIP) and a computerised routine were utilised, respectively, to derive ventilation and to detect VIP₁ and VIP₂ during a standardised field ramp test on a 400 m running track on 81 participants. In addition, average running speed of a competitive 1000 m run (S_1k) was observed as criterion. The predictive value of running speed at VIP₁ (S_VIP1) and the speed range between VIP₁ and VIP₂ in relation to VIP₂ (VIP_SPAN) was analysed via regression analysis. VIP_SPAN rather than running speed at VIP₂ (S_VIP2) was operationalised as a predictor to consider the covariance between S_VIP1 and S_VIP2. S_VIP1 and VIP_SPAN, respectively, provided 58.9% and 22.9% of explained variance in regard to S_1k. Considering covariance, the timing of two ventilatory inflection points provides predictive value in regard to a competitive 1000 m run. This is the first study to apply computerised detection of ventilatory inflection points in a field setting independent on measurements of the respiratory gas exchange and without using any facemasks.  相似文献   

Effects of high-intensity interval training on cardiometabolic risk factors in overweight/obese women     

Abbie E. Smith-Ryan  Eric T. Trexler  Hailee L. Wingfield  Malia N.M. Blue 《Journal of sports sciences》2016,34(21):2038-2046

The purpose of this study was to evaluate two practical interval training protocols on cardiorespiratory fitness, lipids and body composition in overweight/obese women. Thirty women (mean ± SD; weight: 88.1 ± 15.9 kg; BMI: 32.0 ± 6.0 kg · m²) were randomly assigned to ten 1-min high-intensity intervals (90%VO₂ peak, 1 min recovery) or five 2-min high-intensity intervals (80–100% VO₂ peak, 1 min recovery) or control. Peak oxygen uptake (VO₂ peak), peak power output (PPO), body composition and fasting blood lipids were evaluated before and after 3 weeks of training, completed 3 days per week. Results from ANCOVA analyses demonstrated no significant training group differences for any primary variables (P > 0.05). When training groups were collapsed, 1MIN and 2MIN resulted in a significant increase in PPO (?18.9 ± 8.5 watts; P = 0.014) and time to exhaustion (?55.1 ± 16.4 s; P = 0.001); non-significant increase in VO₂ peak (?2.36 ± 1.34 ml · kg^?1 · min^?1; P = 0.185); and a significant decrease in fat mass (FM) (??1.96 ± 0.99 kg; P = 0.011). Short-term interval exercise training may be effective for decreasing FM and improving exercise tolerance in overweight and obese women.  相似文献