基于SIP的VoIP软终端自动测试方法     

叶自宁 《武汉职业技术学院学报》2011,10(5):66-69

VoIP系统已经成为商业应用中重要的一部分,为了促进VoIP应用的健壮性发展,需要一种可以有效检测其安全漏洞的自动安全测试工具。本文提出了一种基于模糊测试的框架,用于检测基于SIP的VoIP软电话安全漏洞。该框架可以自动与软电话用户界面进行交互,并且可以观察软电话的用户界面来检测错误信息。实验证明提出的框架可以检测出以前没有发现的一些漏洞。  相似文献   

一种新的H-CgCr肤色模型的肤色检测方法     

汤三 《许昌学院学报》2011,30(5):73-77

提出一种新的H-CgCr肤色模型进行肤色检测,该模型充分利用色调和色度信息区分肤色像素和非肤色像素.并利用形态学操作去除检测出皮肤区域中毛刺、空洞等噪声.实验结果表明该方法在复杂光照条件下能有效检测出肤色区域.  相似文献   

On theory and methods for advanced detonation-driven hypervelocity shock tunnels     

Zonglin Jiang  Jinping Li  Zongmin Hu  Yunfeng Liu  Hongru Yu 《国家科学评论(英文版)》2020,7(7):1198

This study describes theory and methods for developing detonation-driven shock tunnels in hypervelocity test facilities. The primary concept and equations for high-enthalpy shock tunnels are presented first to demonstrate the unique advantage of shock tubes for aerodynamic ground-based testing. Then, the difficulties in simulating flight conditions in hypervelocity shock tunnels are identified, and discussed in detail to address critical issues underlying these difficulties. Theory and methods for developing detonation drivers are proposed, and relevant progress that has advanced the state of the art in large-scale hypersonic test facilities is presented with experimental verifications. Finally, tailored conditions for detonation-driven shock tunnels are described, laying a solid foundation to achieve long test duration. This interface-matching key issue encountered in developing shock tunnels has been investigated for decades, but not solved for detonation drivers in engineering applications.  相似文献   

On the Performance of Semi- and Nonparametric Item Response Functions in Computer Adaptive Tests     

Carl F. Falk  Leah M. Feuerstahler 《Educational and psychological measurement》2022,82(1):57

Large-scale assessments often use a computer adaptive test (CAT) for selection of items and for scoring respondents. Such tests often assume a parametric form for the relationship between item responses and the underlying construct. Although semi- and nonparametric response functions could be used, there is scant research on their performance in a CAT. In this work, we compare parametric response functions versus those estimated using kernel smoothing and a logistic function of a monotonic polynomial. Monotonic polynomial items can be used with traditional CAT item selection algorithms that use analytical derivatives. We compared these approaches in CAT simulations with a variety of item selection algorithms. Our simulations also varied the features of the calibration and item pool: sample size, the presence of missing data, and the percentage of nonstandard items. In general, the results support the use of semi- and nonparametric item response functions in a CAT.  相似文献   

花样游泳运动员功能性动作能力与力量素质的相关性研究     

陈文佳  章碧玉  沈兆喆 《中国体育科技》2020,(2):71-80,F0003

目的:探讨我国优秀花样游泳运动员功能性动作能力与力量素质的相关性,分析功能动作筛查测试与力量素质测试结果存在的内在联系,从专项视角探讨花样游泳运动项目的训练策略并提出建议。方法:选取国家花样游泳队14名健将级运动员为研究对象,对其进行FMS、握力、上肢力量、股内收肌群力量、躯干核心耐力、下肢爆发力测试,并对测试结果进行相关性分析。结果:1)14名花样游泳运动员FMS测试平均得分为15.21分,有5人测试得分低于运动损伤高风险的临界值(14分);2)FMS测试总分与Keiser坐姿上推(偏相关系数=0.622,P<0.05)、45°股内收肌群横向收缩力量(偏相关系数=0.652,P<0.05)、90°股内收肌群横向收缩力量(偏相关系数=0.746,P<0.01)均呈正相关;3)直线弓步蹲与Keiser坐姿上推(偏相关系数=0.711,P<0.05)、无反向纵跳(偏相关系数=0.661,P<0.05)、有反向纵跳(偏相关系数=0.614,P<0.05)和40 cm跳深跳高(偏相关系数=0.754,P<0.01)均呈正相关;肩部灵活性测试得分与Keiser下蹲上推(偏相关系数=0.575,P<0.05)、45°股内收肌群横向收缩力量(偏相关系数=0.585,P<0.05)以及90°股内收肌群横向收缩力量(r=0.867,P<0.01)均呈正相关,与仰桥耐力呈负相关(偏相关系数=0.701,P<0.05);旋转稳定性与40 cm跳深跳高呈正相关(偏相关系数=0.575,P<0.05)。结论:我国优秀花样游泳运动员髋关节主动灵活性和臀大肌-髂胫束联合等肌群的主动柔韧性较好,但存在膝关节、髋关节稳定性差、躯干核心区肌群控制力不足等问题,受主导臂和主导腿均为右侧影响,运动员身体两侧不平衡明显。运动员FMS测试得分并不能全面反映其力量素质的高低,FMS测试得分与部分力量素质测试结果存在相关性,可能与两种测试均涉及同一动力链结构系统肌群的协同工作和动作存在做功类型的相似性有关。  相似文献   

大学生体质健康测试中运动损伤的调查研究     

朱丽丽  侯毓岭  蒋兰新 《体育科技文献通报》2020,(4):62-63

为了更好地完成《国家学生体质健康标准》的测试工作,本文采用文献资料、逻辑分析、实地考察等方法,对大学生体质健康测试过程中常发生的运动损伤进行了分析,并提出相应的预防措施,为体质健康测试的顺利进行、学生的健康发展、教育主管部门的决策提供了理论依据。  相似文献   

Responses to oral glucose challenge differ by physical activity volume and intensity: A pilot study     

Trevor N. Simper  Cecile Morris  Anthony Lynn  Ciara O'Hagan  Karen Kilner 《运动与健康科学(英文)》2020,9(6):645-650

BackgroundOne-hour postprandial hyperglycemia is associated with increased risk of type 2 diabetes and cardiovascular disease. Physical activity (PA) has short-term beneficial effects on post-meal glucose response. This study compared the oral glucose tolerance test results of 3 groups of people with habitually different levels of PA.MethodsThirty-one adults without diabetes (age 25.9 ± 6.6 years; body mass index 23.8 ± 3.8 kg/m²; mean ± SD) were recruited and divided into 3 groups based on self-reported PA volume and intensity: low activity < 30 min/day of moderate-intensity activity (n = 11), moderately active ≥ 30 min/day of moderate-intensity PA (n = 10), and very active ≥ 60 min/day of PA at high intensity (n = 10). Participants completed an oral glucose tolerance test (50 g glucose) with capillary blood samples obtained at baseline, 15 min, 30 min, 45 min, 60 min, 90 min, and 120 min post-ingestion.ResultsThere were no significant differences between groups for age or body fat percentage or glycated hemoglobin (p > 0.05). The groups were significantly different in terms of baseline glucose level (p = 0.003) and, marginally, for gender (p = 0.053) and BMI (p = 0.050). There was a statistically significant effect of PA on the 1-h postprandial glucose results (p = 0.029), with differences between very active and low activity groups (p = 0.008) but not between the moderately active and low activity groups (p = 0.360), even when baseline glucose level and gender differences were accounted for. For incremental area under the curve there was no significant effect of activity group once gender and body fat percentage had been accounted for (p = 0.401). Those in the low activity group took 15 min longer to reach peak glucose level than those in the very active group (p = 0.012).ConclusionThe results suggest that high levels of PA have a beneficial effect on postprandial blood glucose profiles when compared to low and moderate levels of activity.  相似文献   

主客观信息融合的港口综合能源系统评价指标体系     

何大春  谈健  苏宜强  解翔  宋天立  蔡超  陈曦 《上海海事大学学报》2020,41(3):110-116

为建立绿色港口,实现港口的节能环保,对港口综合能源系统(port integrated energy system,PIES)的评价方法进行研究,提出一种主客观信息融合的PIES评价指标体系,将主观评价与数理统计模型进行结合,兼顾评价过程中的主客观因素,并采用基于马氏距离的统计检验方法对评分矩阵进行修正,实现对PIES的全面评价。通过青岛港董家口港区的调研数据,验证该方法的有效性。  相似文献   

Determination of peak cardiorespiratory fitness parameters in children: which averaging method should we use?     

Joel Blanchard  Samuel Blais  Philippe Chetaille  Michele Bisson  François P. Counil  Thelma H. Girard 《Journal of sports sciences》2019,37(11):1265-1269

The purpose of this study was to identify which averaging methods most accurately measures peak cardiorespiratory fitness (CRF) parameters [peak O₂ uptake (VO₂), peak O₂pulse and peak respiratory exchange ratio (RER)] in a sample of healthy children and adolescents. In this cross-sectional multicenter study, we recruited 278 healthy children aged 12–17 years. We compared the mean peak value of three CRF parameters using the recommended averaging methods (30-second block average) with alternative averaging methods such as moving averages or shorter smoothing periods. We also assessed averaging methods for accuracy by individually reviewing breath-by-breath scatter plots. The 30-second block average method resulted in a lower mean peak VO₂ and in an increased proportion of underestimated peak values. Using a 30-second moving average significantly increased mean peak values which increased accuracy. Similar results were found for peak RER and peak O₂pulse. In conclusion, the currently recommended averaging method (30-second block average) increased the risk of misinterpretation of peak CRF values in children. Using a moving average approach decreased misinterpretation and increased accuracy.  相似文献   

学生体质健康测试第三方机构督查的独立性     

翟继勇  董琴娟 《武汉体育学院学报》2019,53(2):96-101

运用文献资料法、专家访谈法等研究方法,对我国各省份学生体质健康测试第三方机构督查的独立性进行研究。通过对我国各省份学生体质健康测试第三方机构督查独立性的现状、问题、原因及对策的探索,在政策上,可以为教育行政部门改革提供决策思路和参考,在实践上,可以提高学生体质健康测试督查的权威性和有效性,倒逼学生体质健康测试的规范化实施。研究发现,当前我国各省份学生体质健康测试第三方机构督查的独立性差,主要体现在第三方机构与教育厅存在行政隶属关系、存在利益关联、第三方机构工作自主性差3个方面。影响学生体质健康测试第三方机构督查独立性的因素主要为中国传统文化对体育和公民意识的漠视、当事方的利益诉求对第三方机构督查独立性的限制、法规制度缺位、第三方机构发育程度低等。提出保障学生体质健康测试第三方机构督查独立性的对策：教育部对第三方机构督查的责权划分做出设计安排,培养公民意识,扩宽经费来源渠道,第三方机构完善自身治理。  相似文献