检索结果-内蒙古大学图书馆

conference on Material Technologies and applications to Optics, Structures, Components, and Sub-systems IV

作者： Goodman, William A. Nejhad, Mehrdad N. Ghasemi Minei, Brenden M. Stuecker, John N. Anderson, Tristin M. Goodman Technol LLC 9551 Giddings Ave NE Albuquerque NM 87109 USA Univ Hawaii Manoa Dept Mech Engn Hawaii Nanotechnol Labs 2540 Dole St Holmes Hall 302 Honolulu HI 96822 USA Robocasting Enterprises LLC 5660 Pino Ave NE Albuquerque NM 87109 USA

ISBN: (数字)9781510628960

ISBN: (纸本)9781510628960

Of interest to Jet Propulsion Laboratory and multiple NASA cost centers are laser communications telescopes (LCTs) with 30 to 100 cm clear aperture, wavefront error (WFE) less than 62 nm, cumulative WFE and transmission loss not to exceed 3-dB in the far field, advanced thermal and stray light design for operation while sun-pointing (3-degrees from the edge of the sun);-20 degrees C to 50 degrees C operational range (wider range preferred), and areal density <65kg/m(2). Telescope dimensional stability, low scatter, extreme lightweighting, and precision structures are a common theme across the NASA 2017 Physics of the Cosmos (PCOS) and Cosmic Origins (COR) Program Annual Technology Reports. Multiple Priority Tier 1-4 technology gaps can be found, and the higher priorities require a solution in time for the next Decadal Survey. A common solution of interest that has been cited is silicon carbide and 3D printing or additive manufacturing. RoboSiCT technologies provide both. Under NASA SBIR I Contract #80NSSC18P1995 the Goodman Technologies (GT) team performed feasibility demonstrations of 3D printed and additively manufactured off-axis RoboSiCT mirror substrates and coarse and fine threaded RoboSiCT bolts. RoboSiC-S provides the degree of passive athermality required for the LCT optical pathlength and wavefront error stability, concomitant with low areal density mirrors (7.75-10 kg/m(2)) and structures (4-5 kg/m(2)), and a theoretical first unit cost for an LCT with a fast steering mirror is $1.5M, a factor of 3-4 less than current LCTs. Team GT will further explore a preliminary Gregorian LCT on NASA SBIR II Contract #80NSSC19C0138.

关键词： Lasercom telescopes silicon carbide dimensionally stable additive manufacturing 3D printing space optics space opto-mechanical structures trusses booms leading edges thermal protection systems space radiation shielding

来源：评论

学校读者我要写书评

暂无评论

Adaptive sensor Fault Detection and Isolation using Unscented Kalman Filter for Vehicle Positioning

Adaptive Sensor Fault Detection and Isolation using Unscente...

引用

International conference on Intelligent Transportation

作者： Daiki Mori Hideki Sugiura Yoshikazu Hattori Toyota Central R&D Labs. Inc. Nagakute Japan

ISBN: (纸本)9781538670255

There is an increasing demand for sub-meter vehicle localization for advanced safety and autonomous systems. Fault detection and isolation (FDI) for sensor systems, such as camera, LIDAR, GNSS, and V2x has been a challenge because their performances are significantly affected by weather, geographical changes, and even spoofing. In this paper, a sensor FDI using Student's t-distribution based adaptive unscented Kalman filter is presented. The proposed filter evaluate each sensor by Hotelling's T 2 test utilizing the predicted sensor output and its covariance. This method can assess the correlation between data that is generated within the same sensor, for accurate fault detection. In addition, measurement noise is adaptively updated by identifying both the covariance and the degree of freedom of the outlier robust Student's t-distribution. The robustness and accuracy of the localization and measurement noise estimation is confirmed through simulation and an experiment on a highway scenario. Furthermore, the result also shows that the precise FDI can be achieved without any prior information regarding sensor measurement noise. The proposed algorithm enhances the reliability of future position based systems such as autonomous control or V2V safety brake.

关键词： Noise measurement Kalman filters Mathematical model Global navigation satellite system Fault detection Axles Robustness

来源：评论

学校读者我要写书评

暂无评论

Theory of intensity to phase noise conversion of fiber optic sensors using phase generated carrier scheme 8

Theory of intensity to phase noise conversion of fiber optic...

引用

conference on advanced sensor systems and applications VIII

作者： Wang, Zhanghai Li, Dongming Ge, Huiliang Hangzhou Inst Appl Acoust Hangzhou 310023 Zhejiang Peoples R China

ISBN: (纸本)9781510622418

The photodetection intensity noise to demodulated phase noise conversion process of fiber optic sensors using phase generated carrier (PGC) scheme is investigated through theoretical calculation and experimental verification. Several categories of intensity noise are calculated, according to their relation between intensity noise power spectral density and photodetection current. The results revealed that demodulated phase noise power level increases by several decibels over the relative intensity noise power level of detected light power signal. Phase noise power level could also fluctuate with demodulated phase signal. Increase of phase noise power level varies according to the noise type, as well as the fluctuation amplitude. For noises that intensity noise power level unrelated to detected light power, such as electronic noise of detector circuit, phase noise power level increases by about 3.7 dB and do not fluctuate with demodulated phase signal. For noises that intensity noise power level proportional to detected light power, such as signal-amplified spontaneous emission(ASE) beat noise of optical amplifiers, phase noise power level fluctuates with demodulated phase signal by about 5.7 decibels and averagely increases about 3.7 decibels over a 2 pi period of demodulated phase signal. For noises that intensity noise power level proportional to square of detected light power, such as light source relative intensity noise, phase noise power level fluctuates with demodulated phase signal by about 9.0 decibels and averagely increases about 4.8 decibels over a 2 pi period of demodulated phase signal. Verification experiments are demonstrated on electronic noise, ASE-signal beat noise and light source relative intensity noise separately.

关键词： fiber optic sensor intensity to phase noise conversion power spectral density phase generated carrier

来源：评论

学校读者我要写书评

暂无评论

Energy Efficient Control Methods of HVAC systems for Smart Campus

Energy Efficient Control Methods of HVAC Systems for Smart C...

引用

IEEE Green Technologies conference (GreenTech)

作者： Gupta, Smit Petrie, Caleb Rao, Vittal Nutter, Brian Texas Tech Univ Dept Elect & Comp Engn Lubbock TX 79409 USA

ISBN: (纸本)9781538651834

The incorporation of advanced sensor data acquisition techniques, concepts of cyber physical systems, and the Internet of Things (IoT) devices into infrastructures and building energy management systems is enabling the smart city deployments. The main emphasis of this paper is to design and implementation of energy efficient controls into the heating, ventilation, and air conditioning (HVAC) systems of the commercial buildings. These systems are responsible for providing acceptable indoor air quality and thermal comfort to the occupants. By tuning and implementing advanced control systems into the existing HVAC systems, energy consumption can be reduced by 20-30%. The traditional control techniques are compared with two advanced control techniques: Pattern Recognition Adaptive Controller (PRAC) and Model Predictive Control (MPC). The salient features of the advanced control techniques are presented. By utilizing the existing hardware and software systems, the proposed control techniques are implemented on one of the academic buildings of the Texas Tech University campus. The preliminary results obtained in the minimization of simultaneous heating and cooling and energy savings of the HVAC systems are presented in the paper.

关键词： Building energy management systems energy saving by minimizing simultaneous heating and cooling advanced controls for HVAC systems

来源：评论

学校读者我要写书评

暂无评论

RealTime Wireless Monitoring System of CO_2 and CH_4 in Juliaca-Peru

RealTime Wireless Monitoring System of CO_2 and CH_4 in Juli...

引用

IEEE International conference on Intelligent Data Acquisition and advanced Computing systems

作者： Javier Mendoza Montoya Jose Chilo Universidad Andina Néstor Cáceres Velásquez Juliaca Peru University of Gävle

This paper presents a measurement system to greenhouse gases (GHG) monitoring. GHGs are formed by the emission of Carbon Dioxide (CO_2) and Methane (CH_4) from vehicles and near located landfills in Juliaca city in Peru. A wireless system is developed using MOS sensors (MQ2, MQ4, TGS2611 and MQ-135), Arduino-nano, xBee wireless communications modules and the interface to the computer is written in Python. The system was tested in real field measurements and the results show gas concentration difference in different points of the city. We could observe that the CO_2 content in places with a large number of vehicles is high and places with organic waste, like fresch product market, the CH_4 content is also high.

关键词： sensors Pollution measurement Wireless sensor networks Wireless communication Monitoring Urban areas Carbon dioxide

来源：评论

学校读者我要写书评

暂无评论

An Efficient AUV-aided Data Collection in Underwater sensor Networks 32

An Efficient AUV-aided Data Collection in Underwater Sensor ...

引用

32nd IEEE International conference on advanced Information Networking and applications (AINA)

作者： Ghoreyshi, Seyed Mohammad Shahrabi, Alireza Boutaleb, Tuleen Glasgow Caledonian Univ Sch Engn & Built Environm Glasgow Lanark Scotland

ISBN: (纸本)9781538621950

From the view of routing protocols in Underwater sensor Networks (UWSNs), mobile data-gathering mechanisms using Autonomous Underwater Vehicle (AUV) have received significant attention because of data collection capability via short-range communications. In this paper, a new Cluster-based AUV-aided Data Collection scheme (CADC) for large-scale UWSNs is proposed to make a trade-off between energy saving and data gathering latency. Our scheme consists of three phases: discovery phase, clustering phase, and data gathering phase. Neighbouring information is exchanged and then collected by AUV during the discovery phase. The collected information is used in the clustering phase in order to determine the cluster heads and members. Then, the AUV tour is planned such that all cluster heads are visited while shortening the tour length of the AUV. To cluster the sensors and cover their heads with the shortest possible tour, we first propose an optimal algorithm to find the global optimal solution, and then propose an efficient algorithm to obtain the near-optimal solution in the less computational time. CADC is scalable and also applicable in both connected and disconnected networks. In terms of energy-latency trade-off, CADC can effectively keep the tour length short while prolonging the network lifetime compared to those of mobile data-gathering approaches. The effectiveness of CADC is validated through an extensive simulation study which reveals the performance improvement in the packet delivery ratio, energy saving, and data gathering latency.

关键词： sensors Energy consumption Relays Logic gates Clustering algorithms Routing protocols"

来源：评论

学校读者我要写书评

暂无评论

Conductive Hierarchical Hairy Fibers for Highly Sensitive, Stretchable, and Water-Resistant Multimodal Gesture-Distinguishable sensor, VR applications

引用

advanced FUNCTIONAL MATERIALS 2019年第50期29卷 1905808-1905808页

作者： Choi, Seunghoon Yoon, Kukro Lee, Sanggeun Lee, Heon Joon Lee, Jaehong Kim, Da Wan Kim, Min-Seok Lee, Taeyoon Pang, Changhyun Sungkyunkwan Univ SKKU Dept SKKU Adv Inst Nanotechnol SAINT 2066 Seobu Ro Suwon 16419 Gyeonggi Do South Korea Yonsei Univ Sch Elect & Elect Engn Nanobio Device Lab 50 Yonsei Ro Seoul 03722 South Korea Sungkyunkwan Univ SKKU Sch Chem Engn 2066 Seobu Ro Suwon 16419 Gyeonggi Do South Korea Korea Res Inst Stand & Sci Ctr Mech Metrol 267 Gajeong Ro Daejeon 34113 South Korea

Conductive fibers, which are highly adaptable to the morphologies of the human body, are attractive for the development of wearable systems, smart clothing, and textronics to detect various biological signals and human motions. A fiber-based conductive sensor interconnected with hierarchical microhairy architectures, exhibiting remarkable stretchability (<200%) and sensitivity for various stimuli (pressure, stretching, and bending), is developed. For distinguishability of multiple gestures, two hierarchical hairy conductive fibers are twisted to fabricate a fiber-type sensor, which monitors distinct waveforms of electrical signals retrieved from pressure, stretching, and bending. This sensor is highly robust under repeated appliances of external stimuli over multiple cyclic tests of various modes (<2200 cycles for each stimulus). Upon formation of a self-assembled monolayer, it exhibits stable performance even under wet conditions. For practical applications, this sensor can be weaved into a smart glove to demonstrate a pressure and gesture-discernible wearable controller for virtual reality (VR) interface, shedding light on advances in wearable electronics with medical and healthcare functionalities and VR systems.

关键词： biosensors conductive fibers hierarchical structures wearable electronics

来源：评论

学校读者我要写书评

暂无评论

Origin-mediated Sink Mobility Support for Large-scale Phenomena Monitoring in IWSNs 32

Origin-mediated Sink Mobility Support for Large-scale Phenom...

引用

32nd IEEE International conference on advanced Information Networking and applications (AINA)

作者： Kim, Myung-Eun Son, Youngsung Kim, Cheonyong Yim, Yongbin Kim, Sang-Ha Elect & Telecommun Res Inst IoT Res Div Daejeon South Korea Chungnam Natl Univ Dept Comp Engn Daejeon South Korea

ISBN: (纸本)9781538621950

Large-scale phenomena monitoring such as fire or toxic gas monitoring is one of major applications in industrial wireless sensor networks. A multitude of sources stemming from a large-scale phenomenon brings heavy communication overhead to report data to a sink. Many researches have focused on monitoring a large-scale phenomenon and reporting to a static sink with an energy-efficient way. Recently, large-scale phenomena monitoring needs a mobile sink for real-time response. However, the sink mobility support in large-scale phenomenon monitoring brings challenging issues. Given the existing approaches to support sink mobility in individual object detection, a mobile sink should establish one to-many communication with all sources of a large-scale phenomenon for location update. The one-to-many communication between a mobile sink and all sources triggers early energy depletion and thus reduces the network lifetime. In this paper, we propose the origin-mediated communication scheme exploiting a hierarchy-based architecture to resolve the one-to-many communication problem. The origin node builds the virtual backbone network to propagate a location update message on behalf of the mobile sink. Simulation results show that the proposed scheme outperforms all the other work and exhibits significant amounts of savings in terms of the entire network's energy consumption.

关键词： large-scale phenomena monitoring sink mobility energy efficiency industrial wireless sensor networks

来源：评论

学校读者我要写书评

暂无评论

CMNS: An Energy-Efficient Communication Scheme for Wireless sensor Networks 12

CMNS: An Energy-Efficient Communication Scheme for Wireless ...

引用

12th IEEE International conference on advanced Networks and Telecommunications systems (ANTS)

作者： Majumder, Pratham Dash, Lucy Sinha, Koushik Sinha, Bhabani P. Indrashil Univ Dept Comp Sci & Engn Rajpur Gujarat India SOA Univ Dept Comp Sci & Engn Bhubaneswar India Southern Illinois Univ Dept Comp Sci Carbondale IL USA

ISBN: (纸本)9781538681343

A new technique for energy-efficient communication in wireless sensor networks is proposed here which is based on a novel source coding of multiple sensor data coupled with the use of silent communication strategy. The source coding technique exploits high temporal correlation between sensor data by first appropriately interleaving the bits of two consecutive sensor data values and then representing every two consecutive bits of this interleaved dual message by one of four symbol values so that the overall message length is reduced by a factor of two. After that, any occurrence of the same symbol value in consecutive positions of this string is replaced by a null symbol. The transmitter is kept silent during the periods of these null symbols following the strategy of silent communication to save transmitter energy. We propose a hybrid modulation / demodulation technique using non-coherent frequency-shift keying (FSK) and amplitude-shift keying (ASK) to implement this communication scheme, termed as Compression with Multiple Null Symbols (CMNS). From simulation results with various real-life sensor data, we find that CMNS provides transmitter energy savings ranging from 73.16% to 46.6% and receiver energy saving of 50% over conventional BFSK. When compared with other existing schemes, we see from simulation with all these sensor data sets that CMNS provides an improvement over Quint Fibonacci Number System (QFNS), the best known similar scheme, in transmitter energy savings ranging from 9.96% to 113.46% and an improvement in receiver energy savings ranging from 4.85% to 27.94%. These results establish that our proposed scheme is very suitable for multihop communication in low cost wireless sensor network applications.

关键词： Energy-efficient communication wireless sensor networks non-coherent detection communication through silence silent symbol

来源：评论

学校读者我要写书评

暂无评论

Performance evaluation of micro-hydro power plant based on a case study of 2 × 650 kW

引用

AIP conference Proceedings 2022年第1期2453卷

作者： Garry Asattar Candrasa Arif Nur Afandi A. Aripriharta 1Electrical Engineering Universitas Negeri Malang Malang Indonesia 2Smart Power and Advanced Energy Systems (SPAES) Center Batu Indonesia 3Center for Advanced Material for Renewable Energy (CAMRY) Universitas Negeri Malang Malang Indonesia

Indonesia has been acknowledged as a country with abundant renewable energy, one of which is water energy. The potential for water energy in Indonesia has been immense, comprising approximately of75,000 MW. However, from the abundance of existing energy, Indonesia could solely maximize around 7% from the existing capacity. One of the functions is the establishment of a hydroelectric power plant. Mini-hydro Power Plant (MHPP), hereinafter referred to as MHPP, is a small-scale power plant that utilizes hydropower under a capacity of 1 MW generated from irrigation channels, rivers, or natural waterfalls, by utilizing the height of the falls and the amount of discharged water, stipulated in the Regulation of the Minister of Energy and Mineral Resources No. 08 of 2011. Lodagung MHPP, situated in Ludoyo District, Blitar Regency is managed by PT. Jasa Tirta 1. Lodagung MHPP operates by utilizing irrigation canals, originally utilized to channel water from the dam to the rice fields. The Lodagung MHPP has 2 generating units of 2 × 650 kW, initially operating in 2017. Upon observing that the Lodagung MHPP is regarded asa new MHPP, this study aims to analyze the performance evaluation by utilizing Matlab Simulink modeling, further compared with the output power and generated by the generator. The results of the research on the Lodagung MHPP indicated that the Hgross parameter value was 13.25 m, the Hloss value was 2.681 m, and the Hnet was 10.569 m. The power generation for the duration of 10 months obtained the average value of the sensor on the turbine of 1024.72 and power on the generator of 968.40, while the turbine results in the Simulink simulation were 1120.63 and the generator was 1059.18. The comparison result of the power difference between the turbine and generator was 95.91 indicating an error of 8%.

关键词：

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：