A method of detecting dry, icy and wet road surface conditions based on scanniag detection of single wavelength backward power is proposed in this letter. The detector is used to receive the backward scattered power w...A method of detecting dry, icy and wet road surface conditions based on scanniag detection of single wavelength backward power is proposed in this letter. The detector is used to receive the backward scattered power which changes with the incidence angle. The relationship between backward power and incidence angle is used to find out the effective angle range and distinguish method. Experiment and simulation show that it is feasible to classifv these three conditions within incidence angle of 5.3 degree.展开更多
Detection of sulfur-oxidizing bacteria has largely been dependent on targeted gene sequencing technology or traditional cell cultivation, which usually takes from days to months to carry out. This clearly does not mee...Detection of sulfur-oxidizing bacteria has largely been dependent on targeted gene sequencing technology or traditional cell cultivation, which usually takes from days to months to carry out. This clearly does not meet the requirements of analysis for time-sensitive samples and/or complicated environmental samples. Since energy-dispersive X-ray spectrometry(EDS) can be used to simultaneously detect multiple elements in a sample, including sulfur, with minimal sample treatment, this technology was applied to detect sulfur-oxidizing bacteria using their high sulfur content within the cell. This article describes the application of scanning electron microscopy imaging coupled with EDS mapping for quick detection of sulfur oxidizers in contaminated environmental water samples, with minimal sample handling. Scanning electron microscopy imaging revealed the existence of dense granules within the bacterial cells, while EDS identified large amounts of sulfur within them. EDS mapping localized the sulfur to these granules. Subsequent 16S rRNA gene sequencing showed that the bacteria detected in our samples belonged to the genus Chromatium, which are sulfur oxidizers. Thus, EDS mapping made it possible to identify sulfur oxidizers in environmental samples based on localized sulfur within their cells, within a short time(within 24 h of sampling). This technique has wide ranging applications for detection of sulfur bacteria in environmental water samples.展开更多
The active Lamb wave and piezoelectric transducer (PZT)-based structural health monitoring (SHM) technology is a kind of efficient approach to estimate the health state of aircraft structure. In practical applicat...The active Lamb wave and piezoelectric transducer (PZT)-based structural health monitoring (SHM) technology is a kind of efficient approach to estimate the health state of aircraft structure. In practical applications, PZT networks are needed to monitor large scale structures. Scanning many of the different PZT actuator-sensor channels within these PZT networks to achieve on-line SHM task is important. Based on a peripheral component interconnect extensions for instrumentation (PXI) platform, an active Lamb wave and PZT network-based integrated multi-channel scanning system (PXI-ISS) is developed for the purpose of practical applications of SHM, which is compact and portable, and can scan large numbers of actuator-sensor channels and perform damage assessing automatically. A PXI-based 4 channels gain-programmable charge amplifier, an external scanning module with 276 actuator-sensor channels and integrated SHM software are proposed and discussed in detail. The experimental research on a carbon fiber composite wing box of an unmanned aerial vehicle (UAV) for verifying the functions of the PXI-ISS is mainly discussed, including the design of PZTs layer, the method of excitation frequency selection, functional test of damage imaging, stability test of the PXI-ISS, and the loading effect on signals. The experimental results have verified the stability and damage functions of this system.展开更多
An integration processing system of three-dimensional laser scanning information visualization in goaf was developed. It is provided with multiple functions, such as laser scanning information management for goaf, clo...An integration processing system of three-dimensional laser scanning information visualization in goaf was developed. It is provided with multiple functions, such as laser scanning information management for goaf, cloud data de-noising optimization, construction, display and operation of three-dimensional model, model editing, profile generation, calculation of goaf volume and roof area, Boolean calculation among models and interaction with the third party soft ware. Concerning this system with a concise interface, plentiful data input/output interfaces, it is featured with high integration, simple and convenient operations of applications. According to practice, in addition to being well-adapted, this system is favorably reliable and stable.展开更多
In this paper,an Internet of Things(IoT)honeypot scanning and detection system is proposed based on an authorization mechanism.For the functional characteristics of different devices existing in the IoT environment,an...In this paper,an Internet of Things(IoT)honeypot scanning and detection system is proposed based on an authorization mechanism.For the functional characteristics of different devices existing in the IoT environment,an authorization and authentication system was designed based on device MAC and randomly generated key for requesting permissions from devices with asset management and traffic monitoring.Subsequently,an authorized access network model was constructed between devices and the authorization system,which inveigles the scanning requests from unauthorized devices into the IoT honeypot based on the authorized authentication algorithm.Specifically,an IoT honeypot system was built and a data collection module,a data preprocessing module,and a scan detection module were installed in it to perform detection and output feedback on the traffic redirected to the honeypot.The experimental results show that our designed system can efficiently identify whether the device is authorized or not in the IoT system and successfully detect the illegal scanning requests from non-authorized devices.展开更多
Single electron transistors(SETs) are known to be extremely sensitive electrometers owing to their high charge sensitivity. In this work, we report the design, fabrication, and characterization of a silicon-on-insul...Single electron transistors(SETs) are known to be extremely sensitive electrometers owing to their high charge sensitivity. In this work, we report the design, fabrication, and characterization of a silicon-on-insulatorbased SET scanning probe. The fabricated SET is located about 10 m away from the probe tip. The SET with a quantum dot of about 70 nm in diameter exhibits an obvious Coulomb blockade effect measured at 4.1 K. The Coulomb blockade energy is about 18 me V, and the charge sensitivity is in the order of 10^-(5)–10(^-3)e/Hz^(1/2). This SET scanning probe can be used to map charge distribution and sense dynamic charge fluctuation in nanodevices or circuits under test, realizing high sensitivity and high spatial resolution charge detection.展开更多
文摘A method of detecting dry, icy and wet road surface conditions based on scanniag detection of single wavelength backward power is proposed in this letter. The detector is used to receive the backward scattered power which changes with the incidence angle. The relationship between backward power and incidence angle is used to find out the effective angle range and distinguish method. Experiment and simulation show that it is feasible to classifv these three conditions within incidence angle of 5.3 degree.
基金Supported by the Basic Scientific Fund for National Public Research Institutes of China(Nos.GY02-2011T10,2015P07)the Qingdao Talent Program(No.13-CX-20)+1 种基金the National Natural Science Foundation of China(Nos.31100567,41176061)the National Natural Science Foundation for Creative Groups(No.41521064)
文摘Detection of sulfur-oxidizing bacteria has largely been dependent on targeted gene sequencing technology or traditional cell cultivation, which usually takes from days to months to carry out. This clearly does not meet the requirements of analysis for time-sensitive samples and/or complicated environmental samples. Since energy-dispersive X-ray spectrometry(EDS) can be used to simultaneously detect multiple elements in a sample, including sulfur, with minimal sample treatment, this technology was applied to detect sulfur-oxidizing bacteria using their high sulfur content within the cell. This article describes the application of scanning electron microscopy imaging coupled with EDS mapping for quick detection of sulfur oxidizers in contaminated environmental water samples, with minimal sample handling. Scanning electron microscopy imaging revealed the existence of dense granules within the bacterial cells, while EDS identified large amounts of sulfur within them. EDS mapping localized the sulfur to these granules. Subsequent 16S rRNA gene sequencing showed that the bacteria detected in our samples belonged to the genus Chromatium, which are sulfur oxidizers. Thus, EDS mapping made it possible to identify sulfur oxidizers in environmental samples based on localized sulfur within their cells, within a short time(within 24 h of sampling). This technique has wide ranging applications for detection of sulfur bacteria in environmental water samples.
基金Foundation items: National High-tech Research and Development Program of China (2007AA03Z117) National Natural Science Foundation of China (50830201) Graduate Education Innovation Project of Nanjing University of Aeronautics and Astronautics of China (BCXJ09-01).
文摘The active Lamb wave and piezoelectric transducer (PZT)-based structural health monitoring (SHM) technology is a kind of efficient approach to estimate the health state of aircraft structure. In practical applications, PZT networks are needed to monitor large scale structures. Scanning many of the different PZT actuator-sensor channels within these PZT networks to achieve on-line SHM task is important. Based on a peripheral component interconnect extensions for instrumentation (PXI) platform, an active Lamb wave and PZT network-based integrated multi-channel scanning system (PXI-ISS) is developed for the purpose of practical applications of SHM, which is compact and portable, and can scan large numbers of actuator-sensor channels and perform damage assessing automatically. A PXI-based 4 channels gain-programmable charge amplifier, an external scanning module with 276 actuator-sensor channels and integrated SHM software are proposed and discussed in detail. The experimental research on a carbon fiber composite wing box of an unmanned aerial vehicle (UAV) for verifying the functions of the PXI-ISS is mainly discussed, including the design of PZTs layer, the method of excitation frequency selection, functional test of damage imaging, stability test of the PXI-ISS, and the loading effect on signals. The experimental results have verified the stability and damage functions of this system.
基金Project(51274250)supported by the National Natural Science Foundation of ChinaProject(2012BAK09B02-05)supported by the National Key Technology R&D Program during the 12th Five-year Plan of China
文摘An integration processing system of three-dimensional laser scanning information visualization in goaf was developed. It is provided with multiple functions, such as laser scanning information management for goaf, cloud data de-noising optimization, construction, display and operation of three-dimensional model, model editing, profile generation, calculation of goaf volume and roof area, Boolean calculation among models and interaction with the third party soft ware. Concerning this system with a concise interface, plentiful data input/output interfaces, it is featured with high integration, simple and convenient operations of applications. According to practice, in addition to being well-adapted, this system is favorably reliable and stable.
基金This work was supported by project of State Grid Shandong Electric Power Company(No.520627200001).
文摘In this paper,an Internet of Things(IoT)honeypot scanning and detection system is proposed based on an authorization mechanism.For the functional characteristics of different devices existing in the IoT environment,an authorization and authentication system was designed based on device MAC and randomly generated key for requesting permissions from devices with asset management and traffic monitoring.Subsequently,an authorized access network model was constructed between devices and the authorization system,which inveigles the scanning requests from unauthorized devices into the IoT honeypot based on the authorized authentication algorithm.Specifically,an IoT honeypot system was built and a data collection module,a data preprocessing module,and a scan detection module were installed in it to perform detection and output feedback on the traffic redirected to the honeypot.The experimental results show that our designed system can efficiently identify whether the device is authorized or not in the IoT system and successfully detect the illegal scanning requests from non-authorized devices.
基金Project supported by the Instrument Developing Project of the Chinese Academy of Sciences(No.YZ201152)the National Natural Science Foundation of China(No.11403084)+1 种基金the Fundamental Research Funds for Central Universities(Nos.JUSRP51510,JUDCF12032)the Graduate Student Innovation Program for Universities of Jiangsu Province(No.CXLX12_0724)
文摘Single electron transistors(SETs) are known to be extremely sensitive electrometers owing to their high charge sensitivity. In this work, we report the design, fabrication, and characterization of a silicon-on-insulatorbased SET scanning probe. The fabricated SET is located about 10 m away from the probe tip. The SET with a quantum dot of about 70 nm in diameter exhibits an obvious Coulomb blockade effect measured at 4.1 K. The Coulomb blockade energy is about 18 me V, and the charge sensitivity is in the order of 10^-(5)–10(^-3)e/Hz^(1/2). This SET scanning probe can be used to map charge distribution and sense dynamic charge fluctuation in nanodevices or circuits under test, realizing high sensitivity and high spatial resolution charge detection.