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基于YOLO-OpenMax的水声通信信号开集识别方法
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作者 李杰 李勇斌 +2 位作者 郑娄 王彬 黄焱 《信息工程大学学报》 2024年第3期258-264,271,共8页
水声通信信号调制方式随着技术进步从典型的传统调制方式发展为水声通信机厂商私有开发的新型调制方式,这使得现有的水声通信信号闭集调制识别技术实用性受到制约,但现阶段鲜有研究基于深度学习的水声通信信号调制方式的开集识别方法。... 水声通信信号调制方式随着技术进步从典型的传统调制方式发展为水声通信机厂商私有开发的新型调制方式,这使得现有的水声通信信号闭集调制识别技术实用性受到制约,但现阶段鲜有研究基于深度学习的水声通信信号调制方式的开集识别方法。针对此现状,提出一种基于YOLO图像检测识别网络和OpenMax模型的开集识别方法。利用YOLOv5网络的输出特点,将传统OpenMax模型的处理方法进行改进,提出一种两步测试方法,实现了在多径信道下的水声通信信号的开集识别。仿真实验表明:在归一化系数为0.5,信噪比等于10 dB条件下的归一化开集识别准确率达到90%以上,实测数据同样验证了本文方法的有效性。 展开更多
关键词 水声通信 调制方式识别 开集识别 两步测试流程
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Effects of subject’s wakefulness state and health status on approximated entropy during eye opening and closure test of routine EEG examination
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作者 Maen Alaraj Tadanori Fukami Fumito Ishikawa 《Journal of Biomedical Science and Engineering》 2012年第2期75-94,共20页
This study tested a novel method designed to provide useful information for medical diagnosis and treatment. We measured electroencephalography (EEG) during a test of eye opening and closing, a common test in routine ... This study tested a novel method designed to provide useful information for medical diagnosis and treatment. We measured electroencephalography (EEG) during a test of eye opening and closing, a common test in routine EEG examination. This test is mainly used for measuring the degree of alpha blocking and sensitivity during eyes opening and closing. However, because these factors depend on the subject’s awareness, drowsiness can interfere with accurate diagnosis. We sought to determine the optimal EEG frequency band and optimal brain region for distinguishing healthy individuals from patients suffering from several neurophysiological diseases (including dementia, cerebrovascular disorder, schizophrenia, alcoholism, and epilepsy) while fully awake, and while in an early drowsy state. We tested four groups of subjects (awake healthy subjects, drowsy healthy subjects, awake patients and drowsy patients). The complexity of EEG band frequencies over five lobes in the human brain was analyzed using wavelet-based approximate entropy (ApEn). Two-way analysis of variance tested the effects of the two factors of interest (subjects’ health state, and subjects’ wakefulness state) on five different lobes of the brain during eyes opening and closing. The complexity of the theta and delta bands over frontal and central regions, respectively, was significantly greater in the healthy state during eyes opening. In contrast, patients exhibited increased complexity of gamma band activity over the temporal region only, during eyes-close. The early drowsy state and wakefulness state increased the complexity of theta band activity over the temporal region only during eyes-close and eyes-open states respectively, and this change was significantly greater in control subjects compared with patients. We propose that this method may be useful in routine EEG examination, to aid medical doctors and clinicians in distinguishing healthy individuals from patients, regardless of whether the subject is fully awake or in the early stages of drowsiness. 展开更多
关键词 EEG ROUTINE EXAMINATION Eyes opening and Closing test Discrete Wavelet Approximate ENTROPY
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THE BRIEF INTRODUCTION OF CHANGCHUN JINGYUETAN OPEN REMOTE SENSING STUDY AND TEST SITE OF THE CHINESE ACADEMY OF SCIENCES
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《遥感信息》 CSCD 1990年第A02期51-52,共2页
In 1979, the Changchun Jingyuetan Remote Sensing Study and Test Site (RSSTS)began its work, and it was formally established in 1985. The RSSTS is subordinated the Changchun Branch of Chinese Academy of Sciences and is... In 1979, the Changchun Jingyuetan Remote Sensing Study and Test Site (RSSTS)began its work, and it was formally established in 1985. The RSSTS is subordinated the Changchun Branch of Chinese Academy of Sciences and is supported by the Changchun Institute of Geography and Changchun Institute of Optics and Fine Machnics, Chinese Academy of Sciences. It is under the management of the Resource & Environment Bureau of Chinese Academy of Sciences and it is the study base of remote sensing basis and application tests in China. The RSSTS is situated in the Jingyuetan scenic spot of the suburbs of Changchun City, Jilin Province. It is located at 43°40′—43°50′N and 125°18′-125°18′E. 展开更多
关键词 THE BRIEF INTRODUCTION OF CHANGCHUN JINGYUETAN open REMOTE SENSING STUDY AND test SITE OF THE CHINESE ACADEMY OF SCIENCES work SITE
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China Opens Testing Method of Anti-Infective Agents in Cosmetics to Public Consultation
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《China Detergent & Cosmetics》 2018年第4期40-40,共1页
On 14 September, China released a cosmetic testing method standardizing new requirements to test for anti -infective agents in cosmetic products. The draft is for public consultation until 28 Sep, 2018.“Testing Metho... On 14 September, China released a cosmetic testing method standardizing new requirements to test for anti -infective agents in cosmetic products. The draft is for public consultation until 28 Sep, 2018.“Testing Method of Anti-infective Agents in Cosmetics” is used to screen for the presence of 36 kinds of antiinfective agents in cosmetic product types such as liquid water-based, cream, lotion, etc. and determine the quality and quantity by High Performance Liquid Chromatography- Tandem Mass Spectrometry (HPLC-MS/MS). 展开更多
关键词 China opens testING METHOD determine the QUALITY
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基于Open CASCADE的快速干涉检查 被引量:3
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作者 蔡东海 屠立群 《轻工机械》 CAS 2010年第2期82-84,共3页
本文给出了一种快速干涉检查方法,该方法主要包括相对运动确立、模型简化、离散时间表及干涉检查。通过Open CASCADE编程进行实例验证,该方法能快速有效实现虚拟样机中动态仿真时的干涉检查。
关键词 机构学 虚拟样机 动态仿真 干涉检查 open CASCADE软件
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宁心解郁胶囊对慢性应激抑郁模型大鼠Open-Field行为的影响 被引量:2
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作者 孙亚男 邹忆怀 朱陵群 《天津中医药》 CAS 2014年第1期42-46,共5页
[目的]探讨宁心解郁胶囊的抗抑郁作用及可能的机制。[方法]以孤养加慢性轻度不可预见性应激方法建立大鼠抑郁模型,用Open-Field方法进行行为学评定,观察模型大鼠给药前后的行为学变化。[结果]经过孤养加慢性轻度不可预见性应激方法造模... [目的]探讨宁心解郁胶囊的抗抑郁作用及可能的机制。[方法]以孤养加慢性轻度不可预见性应激方法建立大鼠抑郁模型,用Open-Field方法进行行为学评定,观察模型大鼠给药前后的行为学变化。[结果]经过孤养加慢性轻度不可预见性应激方法造模后的大鼠,Open-Field行为学评定中模型组大鼠的总路程、平均速度、中央活动路程、中央活动时间、各角的活动路程和时间均较空白组有统计学差异(P<0.05)。治疗后大鼠的总活动路程、平均速度、中央活动时间、中央活动路程、下边活动路程、下边活动时间、各角的活动路程和时间均较模型组有统计学差异(P<0.05),活动路程较模型组增加,活动时间较模型组增加,且以中剂量组效果显著。[结论]宁心解郁胶囊具有抗抑郁作用,对大鼠抑郁行为有明显改善。 展开更多
关键词 宁心解郁胶囊 慢性应激抑郁模型 open—Field实验 行为学
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应用Open Meta-Analysis软件实现诊断准确性试验的Meta分析 被引量:1
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作者 何倩 吴君怡 +4 位作者 陶圆 许杨鹏 喻亚宇 张超 牛玉明 《中国循证心血管医学杂志》 2016年第9期1029-1032,共4页
Open Meta-Analysis软件是用于二分类数据、连续型数据以及诊断数据Meta分析的开放软件,该软件提供了四种模型来执行诊断准确性试验的Meta分析,即诊断随机效应模型、倒方差混合效应模型、双变量模型和分层综合受试者工作特征曲线法,其... Open Meta-Analysis软件是用于二分类数据、连续型数据以及诊断数据Meta分析的开放软件,该软件提供了四种模型来执行诊断准确性试验的Meta分析,即诊断随机效应模型、倒方差混合效应模型、双变量模型和分层综合受试者工作特征曲线法,其中前两者为单变量模型,只能执行单个指标合并,而后两者为双变量模型,能够对灵敏度和特异度之间的负相关性进行综合分析。本文以实例就Open Meta-Analysis软件实现诊断准确性试验Meta分析做相关简述。 展开更多
关键词 诊断准确性试验 倒方差混合效应模型 双变量模型 HSROC open Meta-Analysis软件
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基于OpenXml的《液压与气动》试题库系统的建设与组卷 被引量:1
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作者 王小萍 黄春 +1 位作者 李昭鸿 彭婧 《装备制造技术》 2015年第11期302-304,共3页
本文通过研究目前试题库的应用技术和发展现状,并根据《液压与气动》课程的特点,进行了机械基础系列课程试题库软件的需求分析,建立了软件模型,提出具有控制整个试卷中各种难度试题的分布的解决方案。同时,使用OpenXml技术实现试题的预... 本文通过研究目前试题库的应用技术和发展现状,并根据《液压与气动》课程的特点,进行了机械基础系列课程试题库软件的需求分析,建立了软件模型,提出具有控制整个试卷中各种难度试题的分布的解决方案。同时,使用OpenXml技术实现试题的预览,并在试题库软件中进行实现组卷、修改和答案生成。该课题以高职液压与气动教学中大量的试题为基础,结合教学的实际需求,利用OpenXml技术完成了《液压与气动》课程试题库软件系统的开发。该软件具有智能性、独立性和开放性的特点。 展开更多
关键词 高职 液压与气动 试题库 openXml技术 组卷
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OpenFlow交换机协议一致性测试集模型研究
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作者 曾帅 殷志坚 《电信网技术》 2016年第5期67-69,共3页
针对当前的Open Flow交换机协议测试技术的研究现状,介绍了两个Open Flow交换机协议一致性测试的测试集模型。
关键词 open Flow交换机 一致性测试 测试集
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基于OpenStack的云测试平台及其性能分析研究 被引量:18
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作者 丁小盼 周浩 +2 位作者 贺珊 陈朱管 郭东辉 《软件》 2015年第1期6-10,共5页
云测试是基于云计算的软件测试新模式。在传统的软件测试中,当测试任务高并发、原有的硬件资源无法满足测试时间要求时,需要更换硬件资源、重新配置测试环境。使用云测试可以实现按需分配硬件资源、无需重新配置测试环境,因而比传统软... 云测试是基于云计算的软件测试新模式。在传统的软件测试中,当测试任务高并发、原有的硬件资源无法满足测试时间要求时,需要更换硬件资源、重新配置测试环境。使用云测试可以实现按需分配硬件资源、无需重新配置测试环境,因而比传统软件测试更能节省测试成本。介绍了如何在OpenStack云平台上配置和运行软件代码覆盖率测试工具SAT。实验表明,当测试任务高并发时,所搭建的云测试平台可以在不用重新配置环境的情况下满足用户对测试时间的要求,降低了用户测试成本。 展开更多
关键词 云计算 openSTACK 软件测试 云测试平台 SAT
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基于Open XML和有限自动机的试卷自动生成系统
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作者 林晓 吴为民 刘勇峰 《顺德职业技术学院学报》 2023年第3期38-43,共6页
考试出题讲究高保密性和高时效性,不允许将题目事先导入数据库再自动生成试卷,需要现场从大量的WORD文档中直接抽取题目并排版生成试卷,这是一项耗时耗力的工作。本研究利用Open XML文档的开源性,直接对DOCX和XLSX文档的内容进行分析读... 考试出题讲究高保密性和高时效性,不允许将题目事先导入数据库再自动生成试卷,需要现场从大量的WORD文档中直接抽取题目并排版生成试卷,这是一项耗时耗力的工作。本研究利用Open XML文档的开源性,直接对DOCX和XLSX文档的内容进行分析读取,并利用有限状态自动机原理对文档的内容进行分类处理,自动生成试卷、答案卷和答题卡文档。实验表明这种方法能够正确按照要求生成试卷,既解决了考试中的保密性要求又提高了工作效率,节省了人力成本。 展开更多
关键词 open XML标准 有限自动机 试卷自动生成
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Overburden management in open pits: options and limits in large limestone quarries 被引量:6
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作者 Claudio Oggeri Taddeo Maria Fenoglio +1 位作者 Alberto Godio Raffaele Vinai 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2019年第2期217-228,共12页
The management of overburden is an important task in open pit exploitations. Site topography and morphology as well as geological and geotechnical properties of natural and remoulded materials are the most important f... The management of overburden is an important task in open pit exploitations. Site topography and morphology as well as geological and geotechnical properties of natural and remoulded materials are the most important factors affecting the disposal phase. Economic and environmental requirements must be followed in order to achieve the best reclamation results, keeping into account site constraints such as slope stability, hauling and dumping issues, and interactions with groundwater. This paper deals with the above mentioned issues, illustrating a rational approach applied on the case of a large limestone quarry where the thickness of the overburden is relevant and the spoil material has to be dumped in a flooded pit. The proposed multidisciplinary approach led to the selection of most suitable methods for excavation, transportation and disposal. The selection was based on a detailed laboratory and site characterisation that defined favorable and adverse factors to be considered during the preliminary study of a large quarrying project. 展开更多
关键词 open pit OVERBURDEN Soil testING LIMESTONE QUARRY Muck ON-SITE testING
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Effect of Coarse Aggregate Size on and Crack Opening in Normal and Relationship between Stress High Strength Concretes 被引量:4
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作者 Jun ZHANG Qian LIU Lin WANG 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2005年第5期691-700,共10页
Fine and coarse aggregates play an important role in the fracture of concrete. However, quantitative information available on the effect of the coarse aggregate size on the fracture properties of concrete is still lim... Fine and coarse aggregates play an important role in the fracture of concrete. However, quantitative information available on the effect of the coarse aggregate size on the fracture properties of concrete is still limited. In the present paper, the effect of coarse aggregate size (single grade of 5~10, 10~16, 16~20 and 20~25 mm) on stress-crack opening (σ-w) relation in normal and high strength concretes (compressive strength of 40 and 80 MPa, respectively) was studied. The investigation was based on three-point bending tests implemented by fictitious crack analysis. The result shows that coarse aggregate size and cement matrix strength significantly influence the shape of σ-w curve. For a given total aggregate content, in normal strength concrete, smaller size of aggregate leads to a high tensile strength and a sharp stress drop after the peak stress. The smaller the coarse aggregate, the steeper the σ-w curve. By contrast, in high strength concrete, the effect of aggregate size on σ-w relation almost vanishes. A similar σ-w relation is obtained for the concrete except for the case of 20~25 mm coarse aggregate size. The stress drop after the peak stress is more significant for high strength concrete than that for normal strength concrete. Meanwhile, the smaller the coarse aggregate size, the higher the flexural strength. Fracture energy and characteristic length increase with increasing coarse aggregate size in both normal and high strength concretes. 展开更多
关键词 Aggregate size Stress-crack opening relation Fracture energy Bending test
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Responses of wind-induced internal pressure in a two-compartment building with a dominant opening and background porosity Part 1:Theoretical formulation and experimental verification 被引量:6
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作者 余先锋 全涌 顾明 《Journal of Central South University》 SCIE EI CAS 2012年第10期2940-2948,共9页
The equations governing wind-induced internal pressure responses for a two-compartment building with a dominant opening and background porosity were derived.The unsteady form of the Bernoulli equation,the law of mass ... The equations governing wind-induced internal pressure responses for a two-compartment building with a dominant opening and background porosity were derived.The unsteady form of the Bernoulli equation,the law of mass conservation,and adiabatic equation were used for the derivation.The precision of the governing equations was verified by a wind tunnel test on a rigid model of a low-rise building.The results show that the governing equations can effectively analyze the wind-induced internal pressure responses.The internal pressure responses in both compartments are suppressed due to the additional damping provided by background porosity.The responses of internal pressure in both compartments,especially in the compartment without an external opening,decrease with increased lumped leakage area. 展开更多
关键词 dominant opening internal pressure background porosity additional damping wind tuunel test
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Optimization of food deprivation and sucrose preference test in SD rat model undergoing chronic unpredictable mild stress 被引量:10
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作者 Li-Wen He Li Zeng +5 位作者 Na Tian Yi Li Tong He Dong-Mei Tan Qian Zhang Yi Tan 《Animal Models and Experimental Medicine》 CSCD 2020年第1期69-78,共10页
Background:The chronic unpredictable mild stress(CUMS)model has long been considered the best model for exploring the pathophysiological mechanisms underlying depression.However,there are no widely recognised standard... Background:The chronic unpredictable mild stress(CUMS)model has long been considered the best model for exploring the pathophysiological mechanisms underlying depression.However,there are no widely recognised standards for strategies for modeling and for behavioral testing.The present study aimed to optimize the protocols for food deprivation and the sucrose preference test(SPT)for the CUMS model.Methods:We first evaluated the effects of different long periods of food deprivation on the body weight of Sprague Dawley(SD)rats by testing food deprivation for 24 hours(8:00-8:00^+),food deprivation for 12 hours during the daytime(8:00-20:00)and food deprivation for 12 hours at night(20:00-8:00^+).Next,we established a SD rat CUMS model with 15 different stimulations,and used body weight measurement,SPT,forced swim test(FST),open field test(OFT)and Morris water maze(MWM)test to verify the success of the modeling.In the SPT,consumption of sucrose and pure water within 1 and 12 hours was measured.Results:Twelve hours of food deprivation during the daytime(8:00-20:00)had no effect on body weight,while 12 hours of food deprivation at night(20:00-8:00^+)and 24 hours of food deprivation(8:00-8:00^+)significantly reduced the mean body weight of the SD rats.When SPT was used to verify the successful establishment of the CUMS rat model,sucrose consumption measured within 12 hours was less variable than that measured within 1 hour.Conclusions:Twelve hours of food deprivation in the daytime(8:00-20:00)may be considered a mild stimulus for the establishment of a CUMS rat model.Measuring sucrose consumption over 12 hours is recommended for SPT. 展开更多
关键词 chronic unpredictable MILD stress forced SWIM test MORRIS water MAZE open field test SUCROSE preference test weight body
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Wind-induced internal pressure fluctuations of structure with single windward opening 被引量:2
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作者 余世策 楼文娟 孙炳楠 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第3期415-423,共9页
A frequency domain method for estimating wind-induced fluctuating internal pressure of structure with single windward opening is presented in this paper and wind tunnel tests were carried out to verify the theory. The... A frequency domain method for estimating wind-induced fluctuating internal pressure of structure with single windward opening is presented in this paper and wind tunnel tests were carried out to verify the theory. The nonlinear differential equation of internal pressure dynamics and iteration algorithm were applied to calculate fluctuating internal pressure and time domain analysis was used to verify the accuracy of the proposed method. A simplified estimation method is also provided and its scope of application is clarified. The mechanism of internal pressure fluctuation is obtained by using the proposed method in the frequency domain and a new equivalent opening ratio is defined to evaluate internal pressure fluctuation. A series of low-rise building models with various openings and internal volumes were designed for wind tunnel tests with results agreeing well with analytical results. It is shown that the proposed frequency domain method based on Gaussian distribution of internal pressure fluctuations can be applied to predict the RMS internal pressure coefficient with adequate accuracy for any opening dimensions, while the simplified method can only be used for structure with single dominant opening. Helmholtz resonance is likely to occur when the equivalent opening ratio is adequately high, and controlling individual opening dimension is an effective strategy for avoiding Helmholtz resonance in engineering. 展开更多
关键词 Single windward opening Internal pressure Iteration algorithm Equivalent opening ratio Wind tunnel test
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Open SSL分组加密的时间侧信道分析 被引量:2
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作者 周伟 郑世珏 《信息技术》 2019年第1期6-10,共5页
随着互联网的快速发展,尤其是网络银行、电子商务等的发展,网络传输过程中的信息安全问题显得尤为重要。Open SSL是对SSL协议的实现,可以用于保证通信双方的数据完整性、保密性,并对通信双方进行身份验证。Open SSL对于侧信道攻击的防... 随着互联网的快速发展,尤其是网络银行、电子商务等的发展,网络传输过程中的信息安全问题显得尤为重要。Open SSL是对SSL协议的实现,可以用于保证通信双方的数据完整性、保密性,并对通信双方进行身份验证。Open SSL对于侧信道攻击的防御较薄弱。对Open SSL加密算法库中7种分组加密算法加密时间的数据样本进行统计分析,最终得出利用时间侧信道进行有效攻击时所需要的最小样本量,对改进Open SSL加密算法及过程提供支持。 展开更多
关键词 open SSL 加密时间 对称加密算法 侧信道 假设检验
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用于开源学习社区的openEuler性能分布式测试实验平台开发 被引量:1
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作者 黄靖茹 李钊兴 +1 位作者 裴喜龙 徐志宇 《软件导刊》 2022年第1期222-225,共4页
为对openEuler开源操作系统的性能进行高质高效的分布式测试,开发一种基于树莓派(RPi)的实验平台。硬件方面以3块RPi通过1台交换机组建局域网,构成1个一主二从的集群,分别采用SD卡和移动硬盘作为主、辅存储器;软件方面以openEuler作为整... 为对openEuler开源操作系统的性能进行高质高效的分布式测试,开发一种基于树莓派(RPi)的实验平台。硬件方面以3块RPi通过1台交换机组建局域网,构成1个一主二从的集群,分别采用SD卡和移动硬盘作为主、辅存储器;软件方面以openEuler作为整个RPi集群的操作系统,Ceph和Seafile分别管理集群的存储资源分配和云存储,通过Frp开放内网IP,支持开源学习社区成员通过互联网访问实验平台、测试等。该实验平台组成简单、成本低廉,后续可通过在openEuler开源学习社区进行推广和大规模学生实验,实现对其各项性能的分布式测试。 展开更多
关键词 开源学习社区 openEuler 操作系统测试 云盘 持续集成
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Dynamic response of support systems during excavation of underground openings
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作者 ?.Aydan 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2019年第5期954-964,共11页
Rockburst,earthquake and blasting cause some dynamic loads on rock support and rock reinforcement system.Elements of rock support and rock reinforcement are generally made of steel bar or cables,which are resistant ag... Rockburst,earthquake and blasting cause some dynamic loads on rock support and rock reinforcement system.Elements of rock support and rock reinforcement are generally made of steel bar or cables,which are resistant against corrosion.These support elements may be subjected to vibrations induced by turbines,vehicle traffic and long-term corrosion in addition to dynamic loading caused by earthquake,rockburst and blasting.In this study,some theoretical,numerical and experimental studies are conducted on rockbolts and rock anchors under shaking and impulsive loading.Then the outcomes of these studies are presented and their practical implications are discussed accordingly. 展开更多
关键词 Rockbolt Dynamic behaviour PULL-OUT test Planar SLIDING UNDERGROUND openINGS SLOPES
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基于OpenSees的墩柱CFRP抗震加固研究 被引量:1
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作者 李晓蒙 《山西建筑》 2016年第16期29-31,共3页
以某墩柱的拟静力试验为基础,通过Open Sees软件,总结了CFRP抗震加固方法,对采用不同层数CFRP加固的墩柱的抗震性能进行了分析,结果表明,采用含纤特征值来表述CFRP加固量的方法简单、有效、合理,经CFRP加固后墩柱的水平承载力、延性水... 以某墩柱的拟静力试验为基础,通过Open Sees软件,总结了CFRP抗震加固方法,对采用不同层数CFRP加固的墩柱的抗震性能进行了分析,结果表明,采用含纤特征值来表述CFRP加固量的方法简单、有效、合理,经CFRP加固后墩柱的水平承载力、延性水平均得到了改善,但增加值不与CFRP层数成正比。 展开更多
关键词 拟静力试验 CFRP open SEES 抗震加固
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