An IP Format Based Algorithm for ZigBee Routing Protocol Optimization

Learning from the conventional practice of network IP address format, this paper proposed an IP-format-based algorithm for ZigBee energy-balanced routing protocol optimization. The algorithm combines node’s cluster address and node’s network short address into a new address and divides the address’s field as IP-format. So that the address will contain information of the network’s topology and provide decision base for a routing algorithm to optimize the original algorithm selection criteria. Meanwhile, in order to improve the ratio of valid data packets and reduce routing overhead, the new algorithm controls the general direction and the number of hops of the RREQ packets to reduce unwarranted data packet transmission. Finally, the simulation carried out on NS platform demonstrates the algorithm’s superiority on network’s delay jitter, overhead and residual energy.

A Plant Image Compression Algorithm Based on Wireless Sensor Network

This paper designs and implements an image transmission algorithm applied to plant information collection based on the wireless sensor network. It can effectively reduce the volume of transmitted data, low-energy, high-availability image compression algorithm. This algorithm mainly has two aspects of improvement measures: the first is to reduce the number of pixels that transmit images, from interlaced scanning to interlaced neighbor scanning;the second is to use JPEG image compression algorithm [1], changing the value of the quantization table in the algorithm [2]. After image compression, the image data volume is greatly reduced;the transmission efficiency is improved;and the problem of excessive data volume during image transmission is effectively solved.

Improved CoSaMP Reconstruction Algorithm Based on Residual Update

A large number of sparse signal reconstruction algorithms have been continuously proposed, but almost all greedy algorithms add a fixed number of indices to the support set in each iteration. Although the mechanism of selecting the fixed number of indexes improves the reconstruction efficiency, it also brings the problem of low index selection accuracy. Based on the full study of the theory of compressed sensing, we propose a dynamic indexes selection strategy based on residual update to improve the performance of the compressed sampling matching pursuit algorithm (CoSaMP). As an extension of CoSaMP algorithm, the proposed algorithm adopts a residual comparison strategy to improve the accuracy of backtracking selected indexes. This backtracking strategy can efficiently select backtracking indexes. And without increasing the computational complexity, the proposed improvement algorithm has a higher exact reconstruction rate and peak signal to noise ratio (PSNR). Simulation results demonstrate the proposed algorithm significantly outperforms the CoSaMP for image recovery and one-dimensional signal.

A Lightweight MVC Framework Based on Code Decoupling Principle

This paper analyzed the problems in the existing framework, and achieved a reasonable framework based on reflection and aspect-oriented programming combined with annotations to map the request parameters, and inversion of the control of the various components. The proposed framework reduced the volume of the application context, and achieved the purpose that dependencies between the various components are controlled by the framework. Based on the problems existing in the known framework, the lightweight MVC framework was implemented and the proposed framework was tested by JMeter test tool. The test results showed that the framework proposed in this paper can respond to requests faster, improve access throughput and enhance application performance and user experience. The framework proposed in this paper combined the functions of MVC and IOC to minimize the volume of external dependencies in the development and greatly improved the efficiency of Web applications development.

Agricultural Traceable and Marketing System Based on iOS-Platform and Wireless Sensor Network

With the rapid development of Things of Internet and its related technologies such as Wireless Sensor Network and remote access system development, its application on agricultural and farming domain has become a new research direction. This paper discusses a practical and efficient system by applying mobile software development technologies and ZigBee communication network. To achieve a compact and flexible iOS-based client, this study takes advantage of Model-View-ViewModel pattern as well as Client/Server style. Several encryption technologies such as Message Digest algorithm and Rivest Shamir Adleman algorithm are combined to ensure information security. Compared to the common portable marketing system, the proposed system also provides accurate growth information which is collected by wireless sensor network, and proposes a more flexible design pattern for mobile client hence obtaining a better performance on iOS devices.

Design and Implementation of Agricultural Information Acquisition System Based on ZigBee and Qt

This paper introduces the design and implementation of agricultural products information collection system based on Qt and ZigBee platform. It consists of three subsystems mainly based in acquisition of images, temperature and humidity values which are passed to the regional gateway. The regional gateway is equipped with embedded Linux operating system and deployed Qt runtime library. The function of transmitting the static image of agricultural products and the temperature and humidity to the regional gateway through the ZigBee Wireless Sensor Network is realized, the pH value, electrical conductivity and light intensity of the growth environment of agricultural products were measured by using Qt library combined with sensor cluster, it can store, display and query the image, electrical conductivity and other parameters in the regional gateway.

A ZigBee-Based Acquisition System for Agricultural Environment Information with Low Power and High Reliability

In order to guarantee the safety of products at modern agriculture, the whole factors of the environment of agricultural production process need to be monitored. That needs to collect a variety of environmental information. In this paper, based on ZigBee technology, a system for crop growth environment information and image information acquisition is implemented. System network scheme can reduce the interchannel interference and enhance ZigBee communication quality. In the process of transmission, the transmission of the image data uses a coding scheme based on historical data comparison. For the image transmission, an intelligent transmission scheme based on generating Feedback Report is proposed, which takes both the quality and efficiency into consideration. Based on these schemes, the system designed in this paper can realize efficient and reliable transmission of agricultural environmental information.

Design and Implementation of E-Commerce Platform Based on Android

This paper introduces the basic functions of the e-commerce system implemented on Android, including user management functions, product search functions, product browsing functions, and product tracking functions, etc. It is necessary to use technologies in Android in order to implement each module function. For example, network communication requires Android’s network request technology and data analysis technology. The display of pictures requires the use of Android controls and cache technology. The traceability of products requires camera scanning technology. And RSA decryption technology and so on. Through the above thread pool technology and the use of caching mechanism, the user experience of UI will be improved and unnecessary network resources consumption will be avoided.

Forward-Backward Synergistic Acceleration Pursuit Algorithm Based on Compressed Sensing

We propose the Forward-Backward Synergistic Acceleration Pursuit (FBSAP) algorithm in this paper. The FBSAP algorithm inherits the advantages of the Forward-Backward Pursuit (FBP) algorithm, which has high success rate of reconstruction and does not necessitate the sparsity level as a priori condition. Moreover, it solves the problem of FBP that the atom can be selected only by the fixed step size. By mining the correlation between candidate atoms and residuals, we innovatively propose the forward acceleration strategy to adjust the forward step size adaptively and reduce the computation. Meanwhile, we accelerate the algorithm further in backward step by fusing the strategy proposed in Acceleration Forward-Backward Pursuit (AFBP) algorithm. The experimental simulation results demonstrate that FBSAP can greatly reduce the running time of the algorithm while guaranteeing the success rate in contrast to FBP and AFBP.

Improvement of Forward-Backward Pursuit Algorithm Based on Weak Selection

Forward-backward pursuit (FBP) algorithm is a novel two-stage greedy approach. However once its forward and backward steps were determined during iteration, it would make computing time increased and affected the reconstruction efficiency. This paper presents a algorithm called forward-backward pursuit algorithm based on weak selection (SWFBP) by introducing threshold strategy into FBP algorithm, and in view of that in the first few iterations, most of the atoms which are selected are right, so this part of atoms are directly incorporated into support set instead of using backward strategy to reduce them. Flexible forward and backward steps accelerate the speed of atom selecting and improve the reconstruction accuracy. We compared SWFBP and FBP algorithm via one-dimensional signal and two-dimensional image reconstruction experiments. The simulation results demonstrate that compared with FBP, SWFBP algorithm has superior performance, including higher PSNR, faster computing speed and lower recovery time.

Genomic insights into the fast growth of paulownias and the formation of Paulownia witches' broom

Paulownias are among the fastest growing trees in the world,but they often suffer tremendous loss of wood production due to infection by Paulownia witches'broom(PaWB)phytoplasmas.In this study,we have sequenced and assembled a high-quality nuclear genome of Paulownia fortunei,a commonly cultivated paulownia species.The assembled genome of P.fortunei is 511.6 Mb in size,with 93.2%of its sequences anchored to 20 pseudo-chromosomes,and it contains 31985 protein-coding genes.Phylogenomic analyses show that the family Paulowniaceae is sister to a clade composed of Phrymaceae and Orobanchaceae.Higher photosynthetic efficiency is achieved by integrating C3 photosynthesis and the crassulacean acid metabolism pathway,which may contribute to the extremely fast growth habit of paulownia trees.Comparative transcriptome analyses reveal modules related to cambial growth and development,photosynthesis,and defense responses.Additional genome sequencing of PaWB phytoplasma,combined with functional analyses,indicates that the effector PaWB-SAP54 interacts directly with Paulownia PfSPLa,which in turn causes the degradation of PfSPLa by the ubiquitin-mediated pathway and leads to the formation of witches'broom.Taken together,these results provide significant insights into the biology of paulownias and the regulatory mechanism for the formation of PaWB.

New insights into the dispersion history and adaptive evolution of taxon Aegilops tauschii in China

Aegilops tauschii,the wild progenitor of wheat D-genome and a valuable germplasm for wheat improvement,has a wide natural distribution from eastern Turkey to China.However,the phylogenetic relationship and dispersion history of Ae.tauschii in China has not been scientifically clarified.In this study,we genotyped 208 accessions(with 104 in China)using dd RAD sequencing and 55K SNP array,and classified the population into six sublineages.Three possible spreading routes or events were identified,resulting in specific distribution patterns,with four sublineages found in Xinjiang,one in Qinghai,two in Shaanxi and one in Henan.We also established the correlation of SNP-based,karyotypebased and spike-morphology-based techniques to demonstrate the internal classification of Ae.tauschii,and developed consensus dataset with 1245 putative accessions by merging data previously published.Our analysis suggested that eight inter-lineage accessions could be assigned to the putative Lineage 3and these accessions would help to conserve the genetic diversity of the species.By developing the consensus phylogenetic relationships of Ae.tauschii,our work validated the hypothesis on the dispersal history of Ae.tauschii in China,and contributed to the efficient and comprehensive germplasm-mining of the species.

Major episodes of horizontal gene transfer drove the evolution of land plants

How horizontal gene transfer(HGT)has contributed to the evolution of animals and plants remains a major puzzle.Despite recent progress,defining the overall scale and pattern of HGT events in land plants has been largely elusive.In this study,we performed systematic analyses for acquired genes in different plant groups and throughout land plant evolution.We found that relatively recent HGT events occurred in char-ophytes and all major land plant groups,but their frequency declined rapidly in seed plants.Two major ep-isodes of HGT events occurred in land plant evolution,corresponding to the early evolution of strepto-phytes and the origin of land plants,respectively.Importantly,a vast majority of the genes acquired in the two episodes have been retained in descendant groups,affecting numerous activities and processes of land plants.We analyzed some of the acquired genes involved in stress responses,ion and metabolite transport,growth and development,and specialized metabolism,and further assessed the cumulative ef-fects of HGT in land plants.

Parallel evolution of twoAIM24 protein subfamilies and their conserved functions in ER stress tolerance in land plants

Despite decades of efforts in genome sequencing and functional characterization,some important protein families remain poorly understood.In this study,we report the classification,evolution,and functions of the largely uncharacterized AIM24 protein family in plants,including the identification of a novel subfamily.We show that two AIM24 subfamilies(AIM24-A and AIM24-B)are commonly distributed in major plant groups.These two subfamilies not only have modest sequence similarities and different gene structures but also are of independent bacterial ancestry.We performed comparative functional investigations on the two AIM24 subfamilies using three model plants:the moss Physcomitrium patens,the liverwort Marchantia polymorpha,and the flowering plant Arabidopsis thaliana.Intriguingly,despite their significant differences in sequence and gene structure,both AIM24 subfamilies are involved in ER stress tolerance and the unfolded protein response(UPR).In addition,transformation of the AIM24-A gene from P.patens into the AIM24-B null mutant of A.thaliana could at least partially rescue ER stress tolerance and the UPR.We also discuss the role of AIM24 genes in plant development and other cellular activities.This study provides a unique example of parallel evolution in molecular functions and can serve as a foundation for further investigation of the AIM24 family in plants.