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An adaptive Markov chain algorithm applied over map-matching of vehicle trip GPS data

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Geo-Spatial Information Science 2021年第3期24卷 484-497页

作者： Bilge Kaan Karamete Louai Adhami Eli Glaser Engineering GeospatialKinetica DB IncArlingtonVAUSA

Markov chains have frequently been applied to match the probable routes with a set of GPS trip data that a pilot vehicle is emitting over a specific graph road network. This class of mapmatching (MM) algorithms presently demonstrates and involve statistical and ad-hoc measures to drive the Markov chain transitional probabilities in picking the best route combinations constrained over the graph road network. In this study, we have devised an adaptive scheme to modify the Markov Chain (MC) kernel window as we move along the GPS samples to reduce the mistakes that can happen by the use of narrower MC widths. The measure for temporarily increasing the MC window width is chosen to be the ratio between the geodesic distance of current route to the actual geodesic distance between each pair of GPS samples. This adaptive use of MC has shown to have hardened the results significantly with tolerable computational cost increase. The details of the overall algorithm are depicted by the example routes extracted from various vehicle trips and the results are shown to validate the usefulness of the algorithm in practice.

关键词： Hidden Markov chain(HMC) map-matching(MM) graph networks

A Blockchain-Based Flexible Data Auditing Scheme for the Cloud Service

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Chinese Journal of Electronics 2021年第6期30卷 1159-1166页

作者： FAN Kefeng LI Fei YU Haiyang YANG Zhen China Electronics Standardization Institute Guangzhou Sequoia db Co. College of Computer Science Beijing University of Technology

Nowdays, cloud storage technology has become a hot topic, and an increasing number of users are concerned with the security of their data in the *** auditing schemes on the cloud are proposed and the introduction of a third-party auditor to assist users in verifying the integrity of cloud data. As a centralized node, the third-party auditor has to communicate with all cloud users and cloud service providers, which becomes the bottleneck of the whole scheme. To solve this problem,we design a blockchain-based flexible cloud data auditing scheme. In our scheme, a decentralized auditing framework is proposed to eliminate the dependency on the thirdparty auditor, which increases the stability, security and performance of the whole scheme. Since the cloud service provider can automatically generates auditing proofs, our scheme can relieve the communication burdens of the cloud service provider. The proposed scheme also adapts the Merkle Hash tree to improve the verification *** analysis and experiments show that the proposed scheme is secure and has better stability and verification efficiency.

关键词： auditing schemes blockchain-based flexible data auditing scheme cloud users third-party auditor cloud service provider auditing decentralized auditing framework cloud storage technology security of data cloud computing data integrity storage management blockchain-based flexible cloud data

Book review of Land Use Transitions and Rural Restructuring in China by Hualou Long

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Journal of Geographical Sciences 2020年第8期30卷 1382-1384页

作者： WOODS Michael Department of Geography and Earth Sciences Aberystwyth UniversityAberystwyth SY233DBUK

The restructuring of rural China is one of the most important elements of global social and economic change in the early twenty-first *** a traditionally rural country,with deep cultural roots in the‘soil’,China has been transformed into a highly advanced and largely urbanized society within the course of a few *** scale and significance of the transformation is equivalent to the industrialization and urbanization of Europe in the nineteenth and early twentieth centuries,and like the European experience a century earlier,its impacts reverberate around the ***,contemporary China is not Victorian-era Europe and whilst there are parallels,we cannot assume that the trajectories,consequences and responses are the same.

关键词： Rural Transition consequences

Methylation reactions at dopaminergic nerve endings, serving as biological off-switches in managing dopaminergic functions

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Neural Regeneration Research 2014年第11期9卷 1110-1111页

作者： Clivel G.Charlton Department of Neuroscience and Pharmacology Meharry Medical College 1005 DB Todd Blvd. Nashville TN USA

The mechanisms for the regulation of synaptic dopamine （DA） include its release from presynaptic vesicles, its interaction with post-synaptic and pre-synaptic DA receptors, the reuptake of DA, via dopamine transporter （DAT）, the diffusion of DA and its metabolism by mono-amine oxidase （MAO） and cate- chol-O-methyl transferase （COMT）. DA controls complex and specialized functions including, movements, behavior, mood, perception, reward, and more recently, neurogenesis （Popolo et al., 2004; Reimer et al., 2013） and neuroregeneration （Hoglinger et al., 2004; Yang et al., 2008）. These functions are varied and of high fidelity. Movement, as an example, requires regulatory mechanisms for initiating, stopping, slowing-down speed- ing-up, changing directions, for governing the relentless urges to move in the young and sedentariness in the old as well as in motor-freezing, catalepsy, tremor and stereotypy.

关键词： DAT serving as biological off-switches in managing dopaminergic functions Methylation reactions at dopaminergic nerve endings COMT

Path Planning Approach in Unknown Environment

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International Journal of Automation and computing 2010年第3期7卷 310-316页

作者： Ting-Kai Wang Quan Dang Pei-Yuan Pan Faculty of Computing London Metropolitan University London N7 8DB UK

This paper presents a new algorithm of path planning for mobile robots, which utilises the characteristics of the obstacle border and fuzzy logical reasoning. The environment topology or working space is described by the time-variable grid method that can be further described by the moving obstacles and the variation of path safety. Based on the algorithm, a new path planning approach for mobile robots in an unknown environment has been developed. The path planning approach can let a mobile robot find a safe path from the current position to the goal based on a sensor system. The two types of machine learning： advancing learning and exploitation learning or trial learning are explored, and both are applied to the learning of mobile robot path planning algorithm. Comparison with A＊ path planning approach and various simulation results are given to demonstrate the efficiency of the algorithm. This path planning approach can also be applied to computer games.

关键词： Path planning fuzzy reasoning unknown environment mobile robot learning algorithm.

Developing rigid constraint for the estimation of pose and structure from a single image

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Journal of Zhejiang University Science 2004年第7期5卷 773-781页

作者：魏宝刚刘永怀 StateKeyLaboratoryofCAD＆CG ZhejiangUniversityHangzhou310027China DepartmentofComputerScience UniversityofWalseAberystwythCeredigionSY233DBWalesUK

Pose and structure estimation from a single image is a fundamental problem in machine vision and multiple sensor fusion and integration. In this paper we propose using rigid constraints described in different coordinate frames to iteratively estimate structural and camera pose parameters. Using geometric properties of reflected correspondences we put forward a new concept, the reflected pole of a rigid transformation. The reflected pole represents a general analysis of transformations that can be applied to both 2D and 3D transformations. We demonstrate how the concept is applied to calibration by proposing an iterative method to estimate the structural parameters of objects. The method is based on a coarse-to-fine strategy in which initial estimation is obtained through a classical linear algorithm which is then refined by iteration. For a comparative study of performance, we also implemented an extended motion estimation algorithm (from 2D-2D to 3D-2D case) based on epipolar geometry.

关键词： Structural constraints 3D-2D problem Rigid transformation

Rough Sets,Their Extensions and Applications

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International Journal of Automation and computing 2007年第3期4卷 217-228页

作者： Richard Jensen Department of Computer Science The University of Wales AberystwythCeredigion SY23 3DBUK

Rough set theory provides a useful mathematical foundation for developing automated computational systems that can help understand and make use of imperfect knowledge. Despite its recency, the theory and its extensions have been widely applied to many problems, including decision analysis, data mining, intelligent control and pattern recognition. This paper presents an outline of the basic concepts of rough sets and their major extensions, covering variable precision, tolerance and fuzzy rough sets. It also shows the diversity of successful applications these theories have entailed, ranging from financial and business, through biological and medicine, to physical, art, and meteorological.

关键词： Rough sets data processing fuzzy sets

CNN Based No-Reference HDR Image Quality Assessment

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Chinese Journal of Electronics 2021年第2期30卷 282-288页

作者： FAN Kefeng LIANG Jiyun LI Fei QIU Puye Digital Technology Research Center China Electronics Standardization Institute School of Electronic Engineering and Automation Guilin University of Electronic Technology Guangzhou Sequoia db Co.

Motivated by the problems of non-universality and over-reliance on the original reference image in High dynamic range(HDR) Image quality assessment(IQA), a convolutional neural network-based algorithm for no-reference HDR image quality assessment is proposed. The Salience detection by self-resemblance(SDSR) algorithm which extracts the salient regions of the HDR image, is used to simulate the human visual attention mechanism. Then a visual quality perception network for training quality prediction models is designed according to the visual characteristics of luminance and contrast sensitivity. And this network consists of an Error estimation network(Error-net), a Perceptual resistance network(PR-net) and a mixing function. The experimental results indicate that the method proposed has high consistency with subjective perception, and the value of assessment metrics Spearman rank-order correlation coefficient(SROCC), Pearson product-moment correlation coefficient(PLCC) and Root mean square error(RMSE)correspondingly reaches 0.941, 0.910 and 8.176 as well. It is comparable with classic full-reference HDR IQA methods.

关键词： convolutional neural network-based algorithm visual perception High dynamic range Image quality assessment human visual attention mechanism Perceptual resistance network convolutional neural nets quality prediction models mean square error methods visual characteristics self-resemblance algorithm visual quality perception network No-Reference HDR Image Quality Assessment feature extraction Error-net original reference image image coding Error estimation network

Larger floods reduce soil CO_(2)efflux during the post-flooding phase in seasonally flooded forests of Western Amazonia

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Pedosphere 2021年第2期31卷 342-352页

作者： Emma M.DOCHERTY Andrew D.THOMAS Department of Geography and Earth Sciences Aberystwyth UniversityAberystwyth SY233DB(UK) School of Geography University of LeedsLeeds LS29JT(UK)

Seasonally flooded várzea forests of Western Amazonia are one of the most productive and biodiverse wetland forests in the ***,data on their soil CO_(2)emissions,soil organic matter decomposition rates,and soil C stocks are *** is a concern because hydrological changes are predicted to lead to increases in the height,extent,and duration of seasonal floods,which are likely to have a significant effect on soil C stocks and ***,with no empirical data,the impact of altered flood regimes on várzea soil C cycles remains *** study quantified the effects of maximum annual flood height and soil moisture on soil CO_(2)efflux rate(R_(s))and soil organic matter decomposition rate(k)in the várzea forests of Pacaya Samiria National Reserve,*** study was conducted between May and August *** results showed that R_(s)(10.6–182.7 mg C m^(-2)h^(-1))and k(0.016–0.078)varied between and within sites,and were considerably lower than the values reported for other tropical *** addition,R_(s)was negatively affected by flood height(P<0.01)and soil moisture(P<0.001),and it decreased with decreasing river levels post flooding(P<0.001).In contrast,k was not affected by any of the above-mentioned *** moisture was the dominant factor influencing R_(s),and it was significantly affected by maximum flood height,even after the floods had subsided(P<0.001).Consequently,we concluded that larger floods will likely lead to reduced R_(s),whilst k could remain unchanged but with decomposition processes becoming more anaerobic.

关键词： C cycle climate change greenhouse gas soil CO_(2)emissions soil moisture soil organic matter decomposition rate tropical forest