检索结果-内蒙古大学图书馆

conference on Infrared Technology and applications xxxVI

作者： Li, Chuan Han, C. J. Skidmore, D. Hess, Cory DRS Reconnaissance Surveillance & Target Acquisit Dallas TX USA

ISBN: (纸本)9780819481245

Significant progress has been made over the past decade on uncooled focal plane array (UFPA) technology development and production capacity at DRS as well as other domestic and overseas suppliers. This resulted in the proliferation of uncooled IR detectors in commercial and military markets. The uncooled detectors are widely used in firefighting, surveillance, industrial process monitoring, machine vision, and medical applications. In the military arena, uncooled detectors are fielded among diverse systems such as weapon sights, driver enhancement viewers, helmet-mounted sights, airborne and ground surveillance sensors including UAVs and robot vehicles. Pixel dimensions have continually decreased with an increase in pixel performance. This paper presents an overview of the DRS 25- and 17-micron pixel pitch uncooled VOx detector technology development and production status. The DRS uncooled FPA products include 320x240 and 640x480 arrays while the larger 1024x768 17-micron pitch array is at engineering prototype quantities. Current production of the 25-micron pitch 320x240 and 640x480 arrays exceeds 5,000 units per month, supporting U. S. military systems such as Army thermal weapon sights (TWS) and driver vision enhancers (DVE). Next generation systems are moving towards the 17-micron pixel pitch detectors. Advancement in small pixel technology has enabled the 17-micron pitch detectors performance to surpass their 25-micron pitch counterparts. To meet future production demand of the 17-micron pitch UFPAs, DRS has made significant investment in production infrastructure to upgrade its tools. These investments include a new DUV stepper, coater, and plasma etcher plus improvements in its manufacturing techniques to enhance yield. These advanced tools reduce the minimum line width in production below 0.35 mu m and are now being used to manufacture the 17-micron 320x240 and 640x480 arrays. To further technology development, DRS continues to engage in R&D activities focus

关键词： sensors Staring arrays Bolometers Signal processing Infrared sensors Detector development Microbolometers Infrared detectors Manufacturing sensor performance

来源：评论

学校读者我要写书评

暂无评论

A highly flexible piezoelectret-fiber pressure sensor based on highly aligned P(VDF-TrFE) electrospun fibers

A highly flexible piezoelectret-fiber pressure sensor based ...

引用

conference on Active and Passive Smart Structures and Integrated systems

作者： Ke, Jun-Yi Chu, Hsin-Jung Hsu, Yu-Hsiang Lee, Chih-Kung Natl Taiwan Univ Inst Appl Mech Taipei Taiwan Natl Taiwan Univ Dept Engn Sci & Ocean Engn Taipei Taiwan

ISBN: (数字)9781510608146

ISBN: (纸本)9781510608139;9781510608146

P(VDF-TrFE) is a ferroelectric material having a strong piezoelectric effect, a good chemical stability, chemical resistance and biocompatibility. Therefore, it is suitable for the development of flexible pressure sensors in biological applications. Using electrospinning method and a drum collector, P(VDF-TrFE) nanofibers are aligned and formed an ultrathin film sheet with a thickness of 15 to 30 mu m. A 140 degrees C annealing process and a corona discharge poling process are conducted to increase the performance of beta phase piezoelectricity. Based on this technology, a highly flexible piezoelectret pressure sensor is developed for measuring muscle movement on the surface of human body. The orientation of electrospun P(VDF-TrFE) fibers and poling direction are studied to enhance the sensitivity of the piezoelectret-fiber pressure sensor. Preliminary study shows that the sensitivity of piezoelectret-fiber pressure sensor can be 110.37 pC/Pa with a high signal to noise ratio. sensor design, experimental studies, and biological application are detailed in this paper.

关键词： Electrospinning flexible sensor P(VDF-TrFE) pressure sensor

来源：评论

学校读者我要写书评

暂无评论

A comparative study on simulation vs. real time deployment in wireless sensor networks

引用

JOURNAL OF systems AND SOFTWARE 2011年第1期84卷 45-54页

作者： Shakshuki, Elhadi M. Malik, Haroon Sheltami, Tarek R. Acadia Univ Jodrey Sch Comp Sci Wolfville NS B4P 2R6 Canada Queens Univ Sch Comp Kingston ON K7L 3N6 Canada

Increasing deployment density and shrinking size of wireless sensor nodes requires small equipped battery size. This means emerging wireless sensor nodes must compete for efficient energy utilization. Medium Access Control (MAC) protocols play a vital role in energy consumption of sensor node as it controls the radio activities. Customized or open source simulators play an important role to measure the performance effectiveness of MAC protocols based on the fact that they are flexible, reduce experimental overhead and cost. Nevertheless, these benefits come at the cost of results accuracy. In this paper, we investigate differences of the behaviour of our agent based S-MAC protocols in real deployment compared to the results produced using our custom based simulator, which ignores the lower layers effects such as packet collision and overhearing. We use network simulator 2 (ns2), an open source simulator, which provides a complete protocol stack. We further try to find and explain the rationale of the variance of results produced by real deployment and that of simulators. (C) 2010 Elsevier Inc. All rights reserved.

关键词： MAC protocol ns2 Wireless sensor network

来源：评论

学校读者我要写书评

暂无评论

An entity maintenance and connection service for sensor networks 03

An entity maintenance and connection service for sensor netw...

引用

1st International conference on Mobile systems, applications and Services

作者： Blum, B Nagaraddi, P Wood, A Abdelzaher, T Son, S Stankovic, J Univ Virginia Dept Comp Sci Charlottesville VA 22904 USA

ISBN: (纸本)1931971099

In this paper we present a middleware architecture for coordination services in sensor networks that facilitates interaction between groups of sensors which monitor different environmental events. It sits on top of the native routing infrastructure and exports the abstraction of mobile communication endpoints maintained at the locations of such events. A single logical destination is created and maintained for every environmental event of interest. Such destinations are uniquely labeled and can be used for communication by application-level algorithms for coordination and sensory data management between the different event locales. For example, they may facilitate coordination, in a distributed intrusion scenario, among nodes in the vicinity of the intruders. We evaluate our middleware architecture using GloMoSim, a wireless network simulator Our results illustrate the success of our architecture in maintaining event-related communication endpoints. We provide an analysis of how architectural and network dependent parameters affect our performance. Additionally we provide a proof of concept implementation on a real sensor network testbed (Berkeley's MICA Motes).

关键词： Information management

来源：评论

学校读者我要写书评

暂无评论

MICROWAVE RADIOMETER sensor TECHNOLOGY RESEARCH FOR EARTH-SCIENCE MEASUREMENTS

MICROWAVE RADIOMETER SENSOR TECHNOLOGY RESEARCH FOR EARTH-SC...

引用

CONF ON MICROWAVE INSTRUMENTATION FOR REMOTE SENSING OF THE EARTH

作者： HARRINGTON, RF BAILEY, MC KENDALL, BM SCHROEDER, LC LAWRENCE, RW CAMPBELL, TG Old Dominion Univ. (United States) NASA Langley Research Ctr. (United States)

ISBN: (纸本)081941171X

A research program has been initiated at NASA Langley Research Center to investigate the critical technologies for developing advanced microwave radiometers suitable for Earth science observations. A significant objective of this research is to enable microwave measurements with adequate spatial resolutions for a number of Earth science parameters, such as sea ice, precipitation, soil moisture, sea surface temperature, and wind speed over oceans. High spatial resolution microwave sensing from space with reasonable swath widths and revisit times favor large real aperture radiometer systems. However, the size requirements for such systems are in conflict with the need to emphasize small launch vehicles. This paper describes a tradeoff between the science requirements, basic operational parameters, test configurations, and expected sensor performance for a satellite radiometer concept. The preliminary designs of real aperture systems utilizing novel light-weight compact-packaging techniques are used as a means of demonstrating this technology.

关键词： Radiometry Reflectors Antennas Microwave radiation Calibration Imaging systems Space operations Spatial resolution Receivers Soil science

来源：评论

学校读者我要写书评

暂无评论

Evaluating the Efficiency of a Night-Time, Middle-Range Infrared sensor for applications in Human Detection and Recognition

Evaluating the Efficiency of a Night-Time, Middle-Range Infr...

引用

conference on Infrared Imaging systems - Design, Analysis, Modeling, and Testing xxIII

作者： Bourlai, Thirimachos Von Dollen, John Mavridis, Nikolaos Kolanko, Christopher W Virginia Univ POB 6201 Morgantown WV 26506 USA

ISBN: (纸本)9780819490339

In law enforcement and security applications, the acquisition of face images is critical in producing key trace evidence for the successful identification of potential threats. In this work we, first, use a near infrared (NIR) sensor designed with the capability to acquire images at middle-range stand-off distances at night. Then, we determine the maximum stand-off distance where face recognition techniques can be utilized to efficiently recognize individuals at night at ranges from 30 to approximately 300 ft. The focus of the study is on establishing the maximum capabilities of the mid-range sensor to acquire good quality face images necessary for recognition. For the purpose of this study, a database in the visible (baseline) and NIR spectrum of 103 subjects is assembled and used to illustrate the challenges associated with the problem. In order to perform matching studies, we use multiple face recognition techniques and demonstrate that certain techniques are more robust in terms of recognition performance when using face images acquired at different distances. Experiments show that matching NIR face images at longer ranges (i.e. greater than about 300 feet or 90 meters using our camera system) is a very challenging problem and it requires further investigation.

关键词： Near infrared Cameras Facial recognition systems Imaging systems Databases Video Detection and tracking algorithms Eye sensors Visible radiation

来源：评论

学校读者我要写书评

暂无评论

Data Mining Approach to Situation-aware sensor Actuation in Wireless sensor Networks 4

Data Mining Approach to Situation-aware Sensor Actuation in ...

引用

4th International conference on Future Generation Communication Technologies (FGCT)

作者： Yoon, Jong P. Ortiz, Juan Mercy Coll Cybersecur Math CS Dobbs Ferry NY 10522 USA

ISBN: (纸本)9781479982677

As wireless sensor networks (WSN) are used in seemingly limitless applications with more sensor types available, large sensor data sets are acquired and transmitted for additional processing. These large data sets may cause network traffics slow unnecessarily. The unfiltered transmission of raw data will also consume the WSN batteries inefficiently. In recent years, a few techniques have been developed for event-driven WSNs and sensor collaborations. For example, in traffic surveillance camera systems, video clips are transmitted in the event of car collision noises. Event-driven services run as a preset parameter of surveillance sensing. It is likely that there may be a false-positive event which drives video data to be transmitted unnecessarily, or false-negative event which misses alarms, both leading to accurate surveillance. This paper proposes an adaptive technique for event-driven WSNs, in which learning from a classification process is employed to fine-tune pre-defined data-driven WSNs. Unlike to traditional data classification techniques, outliers of collected sensor data will be one of the critical data points. The proposed technique functions more proactively by being aware of the environmental situation changes. The contribution of this paper includes an adaptive technique of acquiring and utilizing sensor data.

关键词： collaborating sensors data mining approach

来源：评论

学校读者我要写书评

暂无评论

Miniature Modular sensor for Chemical Species Tomography with Enhanced Spatial Resolution

Miniature Modular Sensor for Chemical Species Tomography wit...

引用

2023 IEEE International conference on Imaging systems and Techniques, IST 2023

作者： Zhang, Rui xia, Jiangnan McCann, Hugh Liu, Chang Ahmed, Ihab Pourkashanian, Mohamed Gough, Andrew Armstrong, Ian Lengden, Michael Johnstone, Walter University of Edinbutgh School of Engineering Edinburgh United Kingdom University of Sheffield Department of Mechanical Engineering Sheffield United Kingdom University of Strathclyde Department of Electronic and Electrical Engineering Glasgow United Kingdom

ISBN: (纸本)9798350330830

The introduction of low/zero-carbon fuels in gas turbine engines poses challenges to the stability and efficiency of combustion processes. As a result, there is a growing demand for advanced imaging techniques that can provide enhanced spatial resolution to monitor and analyze the physiochemical parameters involved. Chemical Species Tomography (CST), utilizing multiple line-of-sight Laser Absorption Spectroscopy (LAS) measurements, has gained popularity in industrial applications due to its non-intrusive nature, robustness, and high sensitivity. Typically, existing CST sensors have few centimeters beam spacing and are highly customized for specific applications. Therefore, the limited beam spacing, and lack of generality pose challenges in terms of providing sufficient sampling and adaptability for wider application scenarios. To enhance the spatial resolution as well as improve the reconfiguration of the CST sensors, this paper proposes a miniature modular CST sensor with a 1cm beam spacing. The use of off-The-shelf components significantly reduces the cost of the system, making it more practical for industrial implementation. Experimental evaluation of the prototype sensor has been conducted for measurements of temperature and water vapor concentration. The results show consistent and accurate measurements, indicating good reliability of the sensor. The proposed miniature modular sensor offers increased flexibility and adaptability to the various CST systems, paving the way for its commercialization in industrial settings. © 2023 IEEE.

关键词： Tomography

来源：评论

学校读者我要写书评

暂无评论

Spatial aggregation query in dynamic geosensor networks

Spatial aggregation query in dynamic geosensor networks

引用

2nd International conference on Space Information Technology

作者： Yi Baolin Feng Dayang xiao Shisong Zhao Erdun Cent China Normal Univ Dept Comp Sci Wuhan 430079 Peoples R China

ISBN: (纸本)9780819469601

Wireless sensor networks have been widely used for civilian and military applications, such as environmental monitoring and vehicle tracking. In many of these applications, the researches mainly aim at building sensor network based systems to leverage the sensed data to applications. However, the existing works seldom exploited spatial aggregation query considering the dynamic characteristics of sensor networks. In this paper, we investigate how to process spatial aggregation query over dynamic geosensor networks where both the sink node and sensor nodes are mobile and propose several novel improvements on enabling techniques. The mobility of sensors makes the existing routing protocol based on information of fixed framework or the neighborhood infeasible. We present an improved location-based stateless implicit geographic forwarding (IGF) protocol for routing a query toward the area specified by query window, a diameter-based window aggregation query (DWAQ) algorithm for query propagation and data aggregation in the query window, finally considering the location changing of the sink node, we present two schemes to forward the result to the sink node. Simulation results show that the proposed algorithms can improve query latency and query accuracy.

关键词： wireless sensor networks spatial aggregation query geosensor networks window query

来源：评论

学校读者我要写书评

暂无评论

Sensing performance of electrically conductive fabrics and dielectric electro active polymers for parachutes

Sensing performance of electrically conductive fabrics and d...

引用

conference on sensors and Smart Structures Technologies for Civil, Mechanical, and Aerospace systems 2011

作者： Favini, Eric Niezrecki, Christopher Manohar, Sanjeev K. Willis, David Chen, Julie Niemi, Eugene Desabrais, Kenneth Charette, Christine Univ Massachusetts Lowell Dept Mech Engn One Univ Ave Lowell MA 01854 USA US Army Natick Soldier Res Dev & Engn Ctr Natick MA 01760 USA

ISBN: (纸本)9780819485434

This paper quantifies the sensing capabilities of novel smart materials in an effort to improve the performance, better understand the physics, and enhance the safety of parachutes. Based upon a recent review of actuation technologies for parachute applications, it was surmised that the actuators reviewed could not be used to effectively alter the drag or lift (i.e. geometry, porosity, or air vent openings) of a parachute during flight. However, several materials showed potential for sensing applications within a parachute, specifically electrically conductive fabrics and dielectric electro-active polymers. This paper introduces several new conductive fabrics and provides an evaluation of the sensing performance of these smart materials based upon test results using mechanical testing and digital image correlation for comparison.

关键词： smart parachute intelligent parachute smart fabric parachute sensor carbon nanotube sensor electrically conductive fabric sensor Danfoss Polypower A/S dielectric electro active polymer sensor

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：