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Key technologies and applications of agricultural energy Internet for agricultural planting and fisheries industry

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Information Processing in Agriculture 2023年第3期10卷 416-437页

作者： Xueqian fu Haosen Niu College of Information and Electrical Engineering China Agricultural UniversityBeijingChina National Innovation Center for Digital Fishery China Agricultural UniversityBeijingChina Key Laboratory of Smart Farming Technologies for Aquatic Animal and Livestock Ministry of Agriculture and Rural AffairsBeijingChina Beijing Engineering and Technology Research Center for Internet of Things in Agriculture BeijingChina

Energy consumption in the agricultural sector is significant,reaching 20%of the total energy consumption in *** Energy Internet,an important extension of Energy Internet in the agricultural field,significantly contributes to agricultural *** technologies of Agricultural Energy Internet are vital factors supporting its *** article systematically reviews the key technologies of Agricultural Energy Internet for two areas:agriculture and *** working mechanisms and power consumption characteristics of some state-of-the-art new-energy agricultural intelligent equipment are *** addition,the principles and profit methods underlying the agro-industrial complementary operation model are ***,against the Agricultural Energy Internet background,the development trends of some state-of-theart new energy agricultural intelligent equipment,agro-industrial complementary,and carbon–neutral technology are proposed in this paper,providing novel perspectives on the promotion of the development of Agricultural Energy Internet and related technological innovation *** unmanned farm is the main form of the future agricultural system,which is powered by the Agricultural Energy Internet based on smart agriculture and a smart *** will become the inevitable trend of modern agriculture to replace oil agriculture with electric *** electricity in farming is mainly generated by renewable *** energy power generation has low carbon emissions and is the future direction for the development of agricultural energy *** addition,the Internet of Things will be further strengthened to realize automation and intelligence of agricultural energy systems。

关键词： Agricultural Energy Internet Agricultural equipment Agricultural planting Fisheries industry Carbon neutrality

TPM-Based Remote Attestation for Wireless Sensor Networks

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Tsinghua Science and Technology 2016年第3期21卷 312-321页

作者： Donglai fu Xinguang Peng Software School of North University of China Taiyuan 030051China School of Computer Science&Technology Taiyuan University of TechnologyTaiyuan 030051China.

It is essential to design a protocol to allow sensor nodes to attest to their trustworthiness for mission- critical applications based on Wireless Sensor Networks （WSNs）. However, it is a challenge to evaluate the trustworthiness without appropriate hardware support. Hence, we present a hardware-based remote attestation protocol to tackle the problem within WSNs. In our design, each sensor node is equipped with a Trusted Platform Module （TPM） which plays the role of a trusted anchor. We start with the formulation of remote attestation and its security. The complete protocol for both single-hop and multi-hop attestations is then demonstrated. Results show the new protocol is effective, efficient, and secure.

关键词： network security wireless sensor networks remote attestation trusted platform module

Reduction rules-based search algorithm for opportunistic replacement strategy of multiple life-limited parts

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Chinese Journal of Aeronautics 2018年第1期31卷 21-30页

作者： Xuyun fu Shisheng ZHONG Department of Mechanical Engineering Harbin Institute of Technology at Weihai

The opportunistic replacement of multiple Life-Limited Parts （LLPs） is a problem widely existing in industry. The replacement strategy of LLPs has a great impact on the total maintenance cost to a lot of equipment. This article focuses on finding a quick and effective algorithm for this problem. To improve the algorithm efficiency, six reduction rules are suggested from the perspectives of solution feasibility, determination of the replacement of LLPs, determination of the maintenance occasion and solution optimality. Based on these six reduction rules, a search algorithm is proposed. This search algorithm can identify one or several optimal solutions. A numerical experiment shows that these six reduction rules are effective, and the time consumed by the algorithm is less than 38 s if the total life of equipment is shorter than 55000 and the number of LLPs is less than 11. A specific case shows that the algorithm can obtain optimal solutions which are much better than the result of the traditional method in 10 s, and it can provide support for determining tobe-replaced LLPs when determining the maintenance workscope of an aircraft engine. Therefore, the algorithm is applicable to engineering applications concerning opportunistic replacement of multiple LLPs in aircraft engines.

关键词： Aircraft engine Maintenance occasion Opportunistic replacement Reduction rules Replacement of life-limited parts

Contribution of tropical cyclone rainfall at categories to total precipitation over the Western North Pacific from 1998 to 2007

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Science China Earth Sciences 2015年第11期58卷 2015-2025页

作者： CHEN FengJiao fu YunFei School of Earth and Space Sciences University of Science and Technology of China State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences

Based on 10 years precipitation data from Tropical Rainfall Measurement Mission （TRMM） Multi-satellite Precipitation Analysis （TMPA） 3B42 and the best track data from China Meteorological Administration （CMA）, the seasonal, monthly and annual contribution of tropical cyclone （TC） precipitation to the total rainfall are analyzed over the Western North Pacific （WNP） during 1998 to 2007 from May to December. The results show that：（1） TC seasonal rainfall contribution ranges from 4% in inland regions to above 40% in ocean-regions of 15°N-25°N. TCs at higher categories contribute much more to the total precipitation. （2） On monthly scale, TCs contribute 60% to the total rainfall regionally during whole TC season, which is the maximum contribution. The peak contribution of TC rainfall averaged in multi-months of the ten years occurs in August （28%） over the whole ocean impacted by TC and in December （23%） over the whole land impacted by TC, respectively. （3） On annual scale, the maximum contribution of TC precipitation to the total rainfall are in 2004 （-30%） over ocean and in 1998 （-20%） over land, respectively. （4） The contribution of TC precipitation to the total rainfall increases 6% （decreases 6%） in El Nino （La Nifia） years compared with neutral years.

关键词： tropical cyclone precipitation contribution 3B42 WNP ENSO

RFID Based e-quality Tracking in Service-oriented Manufacturing Execution System

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Chinese Journal of Mechanical Engineering 2012年第5期25卷 974-981页

作者： fu Yingbin JIANG Pingyu State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong UniversityXi'an 710049China

The method of acquiring the real-time data has influenced the implementation of the manufacturing execution system （MES）. Accompanied with turning the MES into service-oriented manufacturing execution system （so-MES）, real-time e-quality tracking （e-QT）, in which real-time data are computed, has played more and more important roles in manufacturing. This paper presents an e-QT model through the study of real-time status data tracking and quality data collecting. An implementing architecture of the e-QT model is constructed on the basis of radio frequency identification devices （RFID） data-tracking network. In order to develop the e-QT system, some key enabling technologies, such as configuration, data collection, and data processing, etc, are studied. The relation schema between hardware is built for the RFID data-tracking network based on the configuration technique. Real-time data are sampled by using data collecting technique. furthermore, real-time status and quality data in a shop-floor can be acquired in terms of using the real-time data computing method. Finally, a prototype system is developed and a running example is given so as to verify the feasibility of methods proposed in this paper. The proposed research provides effective e-quality tracking theoretical foundation through the use of RFID technology for the discrete manufacturing.

关键词： real-time tracking data collection radio frequency identification devices

Modelling of pressure-strain correlation in compressible turbulent flow

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Acta Mechanica Sinica 2008年第1期24卷 37-43页

作者： Siyuan Huang Song fu Department of Engineering Mechanics Tsinghua University100084 Beijing China

Previous studies carried out in the early 1990s conjectured that the main compressible effects could be associated with the dilatational effects of velocity fluctuation. Later, it was shown that the main compressibility effect came from the reduced pressure-strain term due to reduced pressure fluctuations. Although better understanding of the compressible turbulence is generally achieved with the increased DNS and experimental research effort, there are still some discrepancies among these recent findings. Analysis of the DNS and experimental data suggests that some of the discrepancies are apparent if the compressible effect is related to the turbulent Mach number, Mt. From the comparison of two classes of compressible flow, homogenous shear flow and inhomogeneous shear flow （mixing layer）, we found that the effect of compressibility on both classes of shear flow can be characterized in three categories corresponding to three regions of turbulent Mach numbers： the low-Mr, the moderate-Mr and high-Mr regions. In these three regions the effect of compressibility on the growth rate of the turbulent mixing layer thickness is rather different. A simple approach to the reduced pressure-strain effect may not necessarily reduce the mixing-layer growth rate, and may even cause an increase in the growth rate. The present work develops a new second-moment model for the compressible turbulence through the introduction of some blending functions of Mt to account for the compressibility effects on the flow. The model has been successfully applied to the compressible mixing layers.

关键词： Compressible turbulence Reynolds stresses Second-moment closure Turbulent Mach number Mixing layer

function S-rough sets and two law forecast

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Journal of Systems Engineering and Electronics 2009年第2期20卷 332-338页

作者： fu Haiyan Shi Kaiquan School of Mathematics and System Sciences Shandong Univ. Jinan 250100 P. R. China School of Information Science and Technology Hainan Normal Univ. Haikou 571158 P. R. China

function S-rough sets has the properties of dynamics, heredity, and memory. function S-rough sets is penetrated and crossed with the issue of economic law forecast, then a new forecast model based on function S-rough sets namely the two law forecast model is proposed, which includes upper law forecast model and lower law forecast model; and its＇ implement algorithm is given. Finally, the validity of the model is demonstrated by the forecast for region economic development of Hainan Province.

关键词： function S-rough sets two law forecast dynamic economic system

Unmanned aerial vehicle positioning based on multi-sensor information fusion

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Geo-Spatial Information Science 2018年第4期21卷 302-310页

作者： Wenjun Li Zhaoyu fu The 710th Research Institute of China Shipbuilding Industry Corporation YichangChina

Unmanned aerial vehicle(UAV)positioning is one of the key techniques in the field of UAV *** the high positioning precision of UAV can be achieved through global positioning system(GPS),the frequency of updating signal in GPS is low and the energy consumption of GPS module is huge,which does not satisfy the real-time demand of UAV *** this paper,a multi-sensor information fusion method based on GPS,inertial navigation system(INS),and the visible light sensors is proposed for UAV *** Kalman filter combining with simulated annealing algorithm is used to estimate the position error between GPS or INS and the visible light sensors,and then the motion trajectory is corrected according to this position error ***,the positioning accuracy of UAV can be improved in case of only INS being *** results demonstrate that the proposed method can remarkably improve the positioning accuracy and greatly reduce the energy consumption.

关键词： Kalman filter algorithm simulated annealing algorithm target tracking integrated positioning system

A Numerical Study on Pressure Drop in Microchannel Flow with Different Bionic Micro-Grooved Surfaces

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Journal of Bionic Engineering 2012年第1期9卷 99-109页

作者： Jing Cui Yabo fu School of Airport Civil Aviation University of China Tianjin 30300 P. R. China College of Physics and electronic engineering Taizhou University Taizhou 318000 P. R. China

The studies of bionics reveal that some aquatic animals and winged insects have developed an unsmoothed surface possessing good characteristics of drag reduction. In this paper, four types of bionic surfaces, placoid-shaped, V-shaped, rib- let-shaped, and ridge-shaped grooved surfaces, are employed as the microchannel surfaces for the purpose of reducing pressure loss. Lattice Boltzmann Method （LBM）, a new numerical approach on mescoscopic level, is used to conduct the numerical investigationsr. The results show that the micro-grooved surfaces possess the drag reduction performance. The existence of the vortices formed within the grooves not only decrease the shear force between fluid and wall but also minimize the contact area between fluid and walls, which can lead to a reduction of pressure loss. The drag reduction coefficient （η） for these four types of micro-structures could be generalized as follows： ηridge_shaped 〉 ηv-shaped 〉 ηplacoid-shaped 〉 ηriblet-shaped. Besides, the geometrical optimizations for the ridge-shaped grooves, which have the highest drag reduction performance, are performed as well. The results suggest that, for the purpose of drag reduction, the ridge-shaped grooves with smaller width to height ratio are recommended for the lower Reynolds number flow, while the ridge-shaped grooves with larger width to height ratio are be more suitable for the larger Reynolds number flow.

关键词： microchannel bionic grooves drag reduction lattice Boltzmann method