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我国台湾排污许可监测/检测管理经验及启示——以大气固定源为例 被引量:5
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作者 孙飞翔 刘金淼 +2 位作者 肖俊霞 李媛媛 温英民 《环境与可持续发展》 2017年第6期125-130,共6页
我国台湾环境监测/检测贯穿许可证申请、编写、查核到执法的全过程,有依据、成体系、重细节。本文通过对其进行梳理总结,得出几点启示:一是监测/检测在许可证管理中要有规可依;二是许可证监测/检测需要规范;三是许可证管理中要加大在线... 我国台湾环境监测/检测贯穿许可证申请、编写、查核到执法的全过程,有依据、成体系、重细节。本文通过对其进行梳理总结,得出几点启示:一是监测/检测在许可证管理中要有规可依;二是许可证监测/检测需要规范;三是许可证管理中要加大在线监测技术的应用;四是环境监测信息要主动向公众公开;五是许可制度实施需要加强引入社会力量参与监测/检测;六是要加大惩处,提高企业违法违规代价。 展开更多
关键词 排污许可 监测/检测 大气固定源
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砖石质不可移动文物本体监测/检测技术研究进展 被引量:4
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作者 吴宜峰 赵金鑫 +2 位作者 乔云飞 李爱群 邓扬 《防灾减灾工程学报》 CSCD 北大核心 2022年第3期623-637,共15页
砖石质不可移动文物作为历史文化的重要组成部分,一直受自然灾害、周边环境以及人类活动的影响,其本体健康状况始终处于风险之中。鉴于此,首先总结了砖石质不可移动文物本体的主要病害及成因,包括变形、渗漏水、风化与内部劣化;然后针... 砖石质不可移动文物作为历史文化的重要组成部分,一直受自然灾害、周边环境以及人类活动的影响,其本体健康状况始终处于风险之中。鉴于此,首先总结了砖石质不可移动文物本体的主要病害及成因,包括变形、渗漏水、风化与内部劣化;然后针对不同病害综述了对应的多种监测/检测技术的原理及特征,并根据实际工程案例进一步分析了各监测/检测技术的应用方法;在此基础上对比了各技术的优势与缺陷并给出了实用性的建议。研究发现,针对砖石质不可移动文物本体上述病害的监测/检测技术已取得了一系列进展,监测设备种类多、特征不一,鉴于砖石质不可移动文物的易损性与不可代替性以及各种技术自身的局限性,在技术选择时,需要结合监测的多样化需求,如无损、实时、低成本等,确定出最优的监测方案。最后,根据现有的监测/检测技术研究基础,提出了灵活调整监测策略、提高监测/检测技术的普适性、加强监测/检测内容的针对性、探索多技术的联合应用、注重关键技术与协作模式的创新等若干需要继续探索的问题。 展开更多
关键词 砖石质不可移动文物 监测/检测技术 监测内容 技术原理 技术应用方法
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金属增材制造在线监测/检测技术的研究进展 被引量:3
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作者 肖明颖 范振红 +3 位作者 高华兵 王建东 果春焕 姜风春 《热加工工艺》 北大核心 2020年第24期1-7,共7页
金属增材制造是近年来迅速发展起来的一种先进制造技术,该技术采用离散、沉积成形,无需任何辅助,实现零部件快速制造,已在航空航天、生物医疗、汽车制造等领域获得广泛关注和应用;但金属增材制造工艺可重复性差、产品稳定性不足、产品... 金属增材制造是近年来迅速发展起来的一种先进制造技术,该技术采用离散、沉积成形,无需任何辅助,实现零部件快速制造,已在航空航天、生物医疗、汽车制造等领域获得广泛关注和应用;但金属增材制造工艺可重复性差、产品稳定性不足、产品质量较低,大大限制了该技术的进一步工业应用。在线监测/检测技术能实时监控成形过程,发现制造缺陷,消除上述问题对该技术的工业应用限制。以在线监测/检测的原理为出发点,按照视觉成像、温度场、光谱、声音和电信号等不同信号采集原理分类,综述了在线监测/检测技术在金属增材制造领域的研究现状;分析了现有技术的不足,并对该技术的发展进行了展望。 展开更多
关键词 金属 增材制造 在线监测/检测 研究现状 发展趋势
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NEW ALGORITHM FOR RECEIVER AUTONOMOUS INTEGRITY MONITORING 被引量:4
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作者 杨传森 徐肖豪 +1 位作者 刘瑞华 赵鸿盛 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2010年第2期155-161,共7页
A new integrity metric for navigation systems is proposed based on the measurement domain. Proba-hilistic optimization design offers tools for fault detection by considering the required navigation performance (RNP)... A new integrity metric for navigation systems is proposed based on the measurement domain. Proba-hilistic optimization design offers tools for fault detection by considering the required navigation performance (RNP) parameter and the uncertainty noise. The choice of the proper performance parameter provided the single-valued mapping with the missed detection probability estimates the probability of failure. The desirable characteristics of the residual sensitivity matrix are exploited to increase the efficiency for identifying erroneous observations. The algorithm can be used to support the performance specification and the efficient calculation of the integrity monitoring process. The simulation for non-precision approach (NPA) validates both the viability and the effectiveness of the proposed algorithm. 展开更多
关键词 required navigation performance (RNP) non-precision approach (NPA) receiver autonomous integrity monitoring (RAIM) failure detection and exclusion (FDE)
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Comparative Studies on Detection of Antibodies against Infectious Bursal Disease Virus with Test Strips and Agar Gel Immunodiffusion Method
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作者 张进良 张文通 +3 位作者 胡思顺 毕丁仁 王喜亮 肖运才 《Agricultural Science & Technology》 CAS 2012年第9期1826-1828,共3页
[Objective] This study aimed to compare the detection results of antibodies against infectious bursal disease virus with test strips and agar gel immunodiffusion method. [Method] Antibodies against infectious bursal d... [Objective] This study aimed to compare the detection results of antibodies against infectious bursal disease virus with test strips and agar gel immunodiffusion method. [Method] Antibodies against infectious bursal disease virus in chicken serum were detected using test strips developed in our laboratory, and the results were comparad^with that using traditional agar diffusion method. [Result] The comparative study of the two methods showed that the sensitivity of test strips was eight times over agar gel immunodiffusion; test strips showed higher detection rate in the deter- mination test of 216 clinical samples, with high specificity, easy preservation, and simple and rapid operation, thereby being more suitable for the monitoring of clinical antibodies. [Conclusion] Test strips could replace the existing serological methods, having great promotion and application value in antibody monitoring. 展开更多
关键词 Infectious bursal disease Agar gel immunodiffusion Test strips
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A Study on the Monitoring System for the FMS
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作者 邱广华 陆士毅 王信义 《Journal of Beijing Institute of Technology》 EI CAS 1992年第2期151-157,共7页
Introduces a new monitoring method in FMS explicated in some detail by means of the MSF(Monitoring System of FMS)under development by the au- thors.In order to push FMS technology forword,enhance machining flexibility... Introduces a new monitoring method in FMS explicated in some detail by means of the MSF(Monitoring System of FMS)under development by the au- thors.In order to push FMS technology forword,enhance machining flexibility and the flexibility of human operaters and equipment in a FMS,the authors have made some breakthroughs in traditional ways of single item,unit monitoring and self-han- dling,and suggested the idea of integrated inspection and put the MSF into more practicability.The working status of FMS can be monitored on the CRT of a micro- computer of the MSF,system troubles will be shown with icons,by the flash of the system characteristic symbol or by alarming,and so on.This explores a new way for FMS inspection in a wholly integrated manner. 展开更多
关键词 MONITORING flexible manufacture systems(FMS)/single detection integrated inspection
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Damage alarming for bridge expansion joints using novelty detection technique based on long-term monitoring data 被引量:4
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作者 缪长青 邓扬 +1 位作者 丁幼亮 李爱群 《Journal of Central South University》 SCIE EI CAS 2013年第1期226-235,共10页
Damage alarming and safety evaluation using long-term monitoring data is an area of significant research activity for long-span bridges. In order to extend the research in this field, the damage alarming technique for... Damage alarming and safety evaluation using long-term monitoring data is an area of significant research activity for long-span bridges. In order to extend the research in this field, the damage alarming technique for bridge expansion joints based on long-term monitoring data was developed. The effects of environmental factors on the expansion joint displacement were analyzed. Multiple linear regression models were obtained to describe the correlation between displacements and the dominant environmental factors. The damage alarming index was defined based on the multiple regression models. At last, the X-bar control chart was utilized to detect the abnormal change of the displacements. Analysis results reveal that temperature and traffic condition are the dominant environmental factors to influence the displacement. When the confidence level of X-bar control chart is set to be 0.003, the false-positive indications of damage can be avoided. The damage sensitivity analysis shows that the proper X-bar control chart can detect 0.1 cm damage-induced change of the expansion joint displacement. It is reasonably believed that the proposed technique is robust against false-positive indication of damage and suitable to alarm the possible future damage of the expansion joints. 展开更多
关键词 damage alarming expansion joint TEMPERATURE traffic condition control chart suspension bridge
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ReTweeting Analysis and Prediction in Microblogs: An Epidemic Inspired Approach 被引量:11
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作者 王昊 李义萍 +1 位作者 冯卓楠 冯铃 《China Communications》 SCIE CSCD 2013年第3期13-24,共12页
Microblogs currently play an important role in social communication. Hot topics currently being tweeted can quickly become popular within a very short time as a result of retweeting. Gaining an understanding of the re... Microblogs currently play an important role in social communication. Hot topics currently being tweeted can quickly become popular within a very short time as a result of retweeting. Gaining an understanding of the retweeting behavior is desirable for a number of tasks such as topic detection, personalized message recommendation, and fake information monitoring and prevention. Interestingly, the propagation of tweets bears some similarity to the spread of infectious diseases. We present a method to model the tweets' spread behavior in microblogs based on the classic Susceptible-Infectious-Susceptible (SIS) epidemic model that was developed in the medical field for the spread of infectious diseases. On the basis of this model, future retweeting trends can be predicted. Our experiments on data obtained from the Chinese micro-blogging website Sina Weibo show that the proposed model has lower predictive error compared to the four commonly used prediction methods. 展开更多
关键词 tweets retweeting PREDICTION SIS epidemic model
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Simultaneous Detection of Three Arboviruses Using a Triplex RT-PCR Enzyme Hybridization Assay
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作者 DanDong Shi—hongFu +3 位作者 Li-huaWang ZhiLv Tai-yuanLi Guo.dongLiang 《Virologica Sinica》 SCIE CAS CSCD 2012年第3期179-186,共8页
Arboviruses represent a serious problem to public health and agriculture worldwide. Fast, accurate identification of the viral agents of arbovirus-associated disease is essential for epidemiological surveillance and l... Arboviruses represent a serious problem to public health and agriculture worldwide. Fast, accurate identification of the viral agents of arbovirus-associated disease is essential for epidemiological surveillance and laboratory investigation. We developed a cost-effective, rapid, and highly sensitive one-step "triplex RT-PCR enzyme hybridization" assay for simultaneous detections of Japanese Encephallitis virus (JEV, Flaviviridae), Getah virus (GETV, Togaviridae), and Tahyna virus (TAHV, Bunyaviridae) using three pairs of primers to amplify three target sequences in one RT-PCR reaction. The analytical sensitivity of this assay was 1 PFU/mL for JEV, 10 PFU/mL for GETV, and 10 PFU/mL for TAHV. This assay is significantly more rapid and less expensive than the traditional serological detection and single RT-PCR reaction methods. When "triplex RT-PCR enzyme hybridization" was applied to 29 cerebrospinal fluid (CSF) samples that were JEV-positive by normal RT-PCR assay, all samples were strongly positive for JEV, but negative for GETV and TAHV, demonstrating a good sensitivity, specificity, and performance at CSF specimen detection. 展开更多
关键词 Japanese Encephalitis virus (JEV) Getah Virus (GETV) Tahyna Virus (TAHV) Multiplex RT-PCR Enzyme Hybridization
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Analysis of Detected Avalanches Using Meteorological Data of Nearby Monitoring Stations in Ischgl, Austria
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作者 Lisa Jobstl Arnold Studeregger +2 位作者 Amulf Wurzer Daniel Stock Richard Koschuh 《Journal of Environmental Science and Engineering(B)》 2014年第2期87-90,共4页
A set of detected avalanches from January to April 2012 on a hillside southeast of lschgl, Austria is given. The avalanches are off-the-cut or caused by blast. The meteorological data of two monitoring stations nearby... A set of detected avalanches from January to April 2012 on a hillside southeast of lschgl, Austria is given. The avalanches are off-the-cut or caused by blast. The meteorological data of two monitoring stations nearby the hillside are taken for analysing the weather situation. The meteorological parameters air temperature, wind intensity and wind speed, relative humidity, precipitation and snow depth are investigated for similarities short before and during an avalanche. The avalanches are grouped into three categories and meteorological characteristics are found for each category. Thereby the avalanche hazard for the observed hillside is better assessed and an infrastructure safety by avalanche control due to concerted avalanche blasts is more effective. The result of the analysis shows three kinds of hazard weather conditions, which increase the avalanche hazard: warm air temperatures cause a settlement of the snow pack, but in the beginning of the process a weakening in the snow pack happens. Rapidly decreasing of the air temperature cause cracks in the snow pack and the combination of fresh snow and strong wind speed leads to accumulation of snow on sheltered slopes. 展开更多
关键词 Detected avalanches meteorological weather stations avalanche danger snow pack
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Clinical course of sub-centimeter-sized nodules detected during surveillance for hepatocellular carcinoma
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作者 Yang Won Min Geum-Youn Gwak +5 位作者 Min Woo Lee Moon Seok Choi Joon Hyoek Lee Kwang Cheol Koh Seung Woon Paik Byung Chul Yoo 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第21期2654-2660,共7页
AIM: To evaluate the outcome of sub-centimeter-sized nodules (SCSNs) detected during surveillance for hepatocellular carcinoma (HCC) in patients at risk. METHODS: We retrospectively analyzed a total of 142 patients wi... AIM: To evaluate the outcome of sub-centimeter-sized nodules (SCSNs) detected during surveillance for hepatocellular carcinoma (HCC) in patients at risk. METHODS: We retrospectively analyzed a total of 142 patients with liver cirrhosis or chronic hepatitis B or C without a prior history of HCC in whom a SCSN was detected during HCC surveillance. We calculated the rate of HCC development from SCSNs in the study population and analyzed the differences in the baseline clinical characteristics and imaging features between the patients with SCSNs that eventually developed into HCC and patients with SCSNs that did not develop into HCC.RESULTS: During 667 person-years of follow-up, HCC developed in 33 patients. The calculated HCC development rate was 4.9% per year. The cumulative one-, two-, three- and five-year HCC development rates were 5.6%, 10.6%, 14.1% and 20.4%, respectively. Upon baseline comparison, the HCC group was older (54.4 ± 8.3 years vs 48.9 ± 9.4 years; P = 0.003) and had lower albumin levels (3.56 ± 0.58 g/dL vs 3.84 ± 0.55 g/dL; P = 0.012) and higher baseline alpha-fetoprotein (AFP) levels (8.5 ng/mL vs 5.4 ng/mL; P = 0.035) compared to the non-HCC group. Nodule pattern and initial radiologic diagnosis also differed between the two groups. Multivariate analysis revealed that age [P = 0.012, odds ratio (OR) =1.075, 95% confidence interval (CI) =1.016-1.137], sex (P = 0.009, OR = 3.969, 95% CI: 1.403-11.226), and baseline AFP level (P = 0.024, OR = 1.039, 95% CI: 1.005-1.073) were independent risk factors for developing HCC. CONCLUSION: The overall risk of HCC development in patients with SCSNs is similar to that in liver cirrhosis patients. Patients with these risk factors need to be closely monitored during follow-up. 展开更多
关键词 Chronic liver disease Hepatocellular carcinoma Risk factor Sub-centimeter-sized nodule
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Utilization of Data Communication according to the IEC61850 Standard for Nuclear Power Plant Electrical Equipment Testing 被引量:1
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作者 Milos Kaska Oto Marecek 《Journal of Energy and Power Engineering》 2014年第4期765-769,共5页
This paper deals with an integration of directly measured electrical parameters with data acquired by data communication from protections and terminals into an advanced monitoring system. Based on the periodic test, t... This paper deals with an integration of directly measured electrical parameters with data acquired by data communication from protections and terminals into an advanced monitoring system. Based on the periodic test, the authors of this paper present the possibility of an extended evaluation and more accurate analysis of transient and failure events. For periodical testing, as implemented during the commissioning of power plants in the Czech Republic, a monitoring system of electrical equipment has been used, to record the courses of important electrical parameters and thus, proving the proper functioning of complex technological systems in various operation modes. Data from monitoring system were used to prove the successful results of the test or as a base data for further analysis of failures. The monitoring system has proved itself as a very useful device also when recording unexpected failure events, the cause of which was very quickly and accurately detected by the follow-up analysis. Initially, only the voltage and current data from measuring transformers, analogue transducers and contact relays were used as input data for the monitoring system. After the implementation of new digital protection technology and controlling terminals with inner data recorder, the data from digital devices could be also utilized for the monitoring system. 展开更多
关键词 Power plant data communication emergency source TRANSIENT FAILURE TERMINAL electrical protection.
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Secure Data Aggregation Approach Based on Monitoring in Wireless Sensor Networks 被引量:1
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作者 Dong Xiaomei Li Shanshan 《China Communications》 SCIE CSCD 2012年第6期14-27,共14页
In order to avoid internal attacks during data aggregation in wireless sensor networks, a grid-based network architecture fit for monitoring is designed and the algorithms for network division, initialization and grid... In order to avoid internal attacks during data aggregation in wireless sensor networks, a grid-based network architecture fit for monitoring is designed and the algorithms for network division, initialization and grid tree construction are presented. The characteristics of on-off attacks are first studied and monitoring mechanisms are then designed for sensor nodes. A Fast Detection and Slow Recovery (FDSR) algorithm is proposed to prevent on-off attacks by observing the behaviors of the nodes and computing reputations. A recovery mechanism is designed to isolate malicious nodes by identifying the new roles of nodes and updating the grid tree. In the experiments, some situations of on-off attacks are simulated and the results are compared with other approaches. The experimental results indicate that our approach can detect malicious nodes effectively and guarantee secure data aggregation with acceptable energy consumption. 展开更多
关键词 data aggregation wireless sensor net-work MONITORING on-off attack RECOVERY
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Computational Study of the A0 Scattered Field Due to an Edge Delamination
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作者 Nithurshan Nadarajah Benjamin Steven Vien +1 位作者 Wing Kong Chiu L. R. Francis Rose 《Journal of Mechanics Engineering and Automation》 2015年第4期229-236,共8页
Delamination detection presents a pertinent problem for SHM be no visible signs of the damage on the surface of the structure. (structural health monitoring), as in most cases, there may This study investigates the ... Delamination detection presents a pertinent problem for SHM be no visible signs of the damage on the surface of the structure. (structural health monitoring), as in most cases, there may This study investigates the scattering of a zeroth-order anti-symmetric (A0) Lamb wave mode by an edge delamination using the commercial FE (finite element) package ABAQUS. The Ao Lamb mode is chosen because the corresponding stress distribution is more sensitive to delamination than is the case for symmetric modes. The paper presents results for the scatter field for various angles of incidence, and for varying defect sizes. The regime of small defect size relative to the incident wavelength is of particular interest for SHM as it corresponds to early damage detection. It is shown that, in this regime the scattered field appears to originate from a point source at the origin of the delamination, and the corresponding amplitude is linearly proportional to area of the delamination. These results can be used to guide the use of Lamb waves to detect and quantify edge delamination in plate-like structures. 展开更多
关键词 Structural health monitoring Lamb waves wave scattering delamination damage.
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Orthogonal nonnegative matrix factorization based local hidden Markov model for multimode process monitoring 被引量:3
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作者 Fan Wang Honglin Zhu +1 位作者 Shuai Tan Hongbo Shi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第7期856-860,共5页
Traditional data driven fault detection methods assume that the process operates in a single mode so that they cannot perform well in processes with multiple operating modes. To monitor multimode processes effectively... Traditional data driven fault detection methods assume that the process operates in a single mode so that they cannot perform well in processes with multiple operating modes. To monitor multimode processes effectively,this paper proposes a novel process monitoring scheme based on orthogonal nonnegative matrix factorization(ONMF) and hidden Markov model(HMM). The new clustering technique ONMF is employed to separate data from different process modes. The multiple HMMs for various operating modes lead to higher modeling accuracy.The proposed approach does not presume the distribution of data in each mode because the process uncertainty and dynamics can be well interpreted through the hidden Markov estimation. The HMM-based monitoring indication named negative log likelihood probability is utilized for fault detection. In order to assess the proposed monitoring strategy, a numerical example and the Tennessee Eastman process are used. The results demonstrate that this method provides efficient fault detection performance. 展开更多
关键词 Multimode processFault detectionHidden Markov modelOrthogonal nonnegative matrix factorization
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A virtual machine-based invasion detection system for the virtual computing environment
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作者 曾宇 Wang Jie +2 位作者 Sun Ninghui Li Jun Nie Hua 《High Technology Letters》 EI CAS 2006年第4期379-384,共6页
Under virtualization idea based on large-scale dismantling and sharing, the implementing of network interconnection of calculation components and storage components by loose coupling, which are tightly coupling in tra... Under virtualization idea based on large-scale dismantling and sharing, the implementing of network interconnection of calculation components and storage components by loose coupling, which are tightly coupling in traditional server, achieves computing capacity, storage capacity and service capacity distri- bution according to need in application-level. Under the new server model, the segregation and protection of user space and system space as well as the security monitoring of virtual resources are the important factors of ultimate security guarantee. This article presents a large-scale and expansible distributed invasion detection system of virtual computing environment based on virtual machine. The system supports security monitoring management of global resources and provides uniform view of security attacks under virtual computing environment, thereby protecting the user applications and system security under capacity services domain. 展开更多
关键词 virtual computing environment oriented virtual machine-based invasion detection system (VIDS) capacity services computing
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The Air Pollution Concern within the Holy Prophet Mosque in AI.Madianh AI-Munawarah
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作者 A.A. Bazzaz A.K. Al-Juhani +1 位作者 N.S. Al-Erwi K.N. Kurdi 《Journal of Environmental Science and Engineering》 2011年第5期550-556,共7页
Using air pollution detecting equipments ITX, ATX620 and IBRID-MX6 Multi gas monitors a pioneer research was carried out to assess the levels of the exhausted gas emission in double-floored car parks of the Holy Proph... Using air pollution detecting equipments ITX, ATX620 and IBRID-MX6 Multi gas monitors a pioneer research was carried out to assess the levels of the exhausted gas emission in double-floored car parks of the Holy Prophet Mosque in Al-Madinah A l-Munawarah from early 12:00 to 14:00 of Friday and from 19:00 to 22:30 at holy month, Ramadan. The percentage of both carbon monoxide (CO) and nitrogen dioxide (NO2) had significantly increased (p 〈 0.05-0.005). The peak levels of these air pollutants were between 13:15-13:20 during Fridays. The increase in the emission of these exhausted gases was concomitant with the significant decrease (p 〈 0.05) in oxygen (02) levels but the latter recovered its levels after 13:20 hours. The arithmetic total mean density of vehicle per minute (vpm) at Salam Road, the busiest road of Al-Madinah, during hours (07:00-09:00), (13:00-15:00) and (17:00-19:00) of both Friday and Saturdays respectively were (8/45, 16/40 and 36/43). The increase in air pollution has been attributed to a dramatic increase in number of public cars use the car parks during these times, the consequent congestion at entries, the excess or/and poor consumption of fuels being utilized and the inadequate ventilation. 展开更多
关键词 Air pollution holy prophet mosque Al-Madinah Al-Munawarah.
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A Method of Peak Detecting for Nanosecond Pulse in Optical Performance Monitoring System
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作者 FENG Lihui ZHANG Qing +2 位作者 LIU Xiang ZUO Lin YANG Aiying 《China Communications》 SCIE CSCD 2014年第2期78-82,共5页
In optical performance monitoring system,the analog to digital converter is needed to detect the peak of nanosecond pulse and get the signal envelope.A scheme based on a designed anti-aliasing filter and analog to dig... In optical performance monitoring system,the analog to digital converter is needed to detect the peak of nanosecond pulse and get the signal envelope.A scheme based on a designed anti-aliasing filter and analog to digital converter is proposed to broaden the nanosecond pulse and make it easier for the analog to digital converter to catch the peak of the nanosecond pulse.The experimental results demonstrate that,with the proposed scheme,the optical performance system needs less time to get the recovered eye-diagram of high speed optical data signal,and is robust to phase mismatch in the analog to digital converter circuit. 展开更多
关键词 optical performance monitoringsystem (OPM) pulse peak detection anti-aliasing filter analog-to-digital converter
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Monitoring Freeway Incident Detection Using a Hotelling T2 Control Chart
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作者 Joonse Lim Young Seon Jeong Youngsul Jeong 《Computer Technology and Application》 2012年第5期361-367,共7页
In real-life freeway transportation system, a few number of incident observation (very rare event) is available while there are large numbers of normal condition dataset. Most of researches on freeway incident detec... In real-life freeway transportation system, a few number of incident observation (very rare event) is available while there are large numbers of normal condition dataset. Most of researches on freeway incident detection have considered the incident detection problem as classification one. However, because of insufficiency of incident events, most of previous researches have utilized simulated incident events to develop freeway incident detection models. In order to overcome this drawback, this paper proposes a wavelet-based Hotelling 7a control chart for freeway incident detection, which integrates a wavelet transform into an abnormal detection method. Firstly, wavelet transform extracts useful features from noisy original traffic observations, leading to reduce the dimensionality of input vectors. Then, a Hotelling T2 control chart describes a decision boundary with only normal traffic observations with the selected features in the wavelet domain. Unlike the existing incident detection algorithms, which require lots of incident observations to construct incident detection models, the proposed approach can decide a decision boundary given only normal training observations. The proposed method is evaluated in comparison with California algorithm, Minnesota algorithm and conventional neural networks. The experimental results present that the proposed algorithm in this paper is a promising alternative for freeway automatic incident detections. 展开更多
关键词 Freeway incident incident detection algorithms Hotelling T2 control chart wavelet transforms feature selection.
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Wireless environmental monitoring system for transformer substation based on acoustic sensor
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作者 朱昌平 Huang Yon.gliang Shan Minglei 《High Technology Letters》 EI CAS 2012年第4期394-400,共7页
In this paper, an indoor environmental monitoring solution is proposed for the transformer sub- station system by using the ZigBee technology. It mainly analyzes the principle of sulfur hexafluoride sensor based on th... In this paper, an indoor environmental monitoring solution is proposed for the transformer sub- station system by using the ZigBee technology. It mainly analyzes the principle of sulfur hexafluoride sensor based on the acoustic method and puts forward a difference data processing method of single- channel and temperature compensation point at power consumption issues for sensor detection. The method not only reduces the sensor power consumption, but also ensures the accuracy and extends the lifetime of wireless sensor nodes effectively. This paper also analyzes the design of the base sta- tion mode, and demonstrates the running processes of routers and sensors. The feasibility of the pro- posed approach has been testified and proved. 展开更多
关键词 environmental monitoring acoustic sensor ZigBee wireless network CC2430
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