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Reversible data Hiding Based on Varying Radix Numeral System

Computers, Materials & Continua 2021年第10期69卷 283-300页

作者： J.Hemalatha S.Geetha R.Geetha C.Balasubramanian daniela Elena Popescu d.Jude Hemanth AAA College of Engineering and Technology SivakasiIndia SCOPE VIT UniversityChennaiIndia SENSE VIT UniversityChennaiIndia department of CSE Kalasalingam Academy of Research and EducationIndia Faculty of Electrical Engineering and Information Technology University of OradeaOradeaRomania department of ECE Karunya Institute of Technology and SciencesCoimbatoreIndia

A novel image reversible data-hiding scheme based on primitive and varying radix numerical model is presented in this *** varying radix,variable sum of data may be embedded in various pixels of *** scheme is made adaptive using the correlation of the neighboring *** are embedded as blocks of non-uniform length in the high-frequency regions of the rhombus mean interpolated image.A higher amount of data is embedded in the high-frequency regions and lesser data in the low-frequency regions of the *** size of the embedded data depends on the statistics of the pixel distribution in the cover *** of the major issues in reversible data embedding,the location map,is minimized because of the interpolation *** technique,which is actually LSB matching,embeds only the residuals of modulo radix into the LSBs of each *** attacks on this RdH technique will be able to decode the hidden content in the marked *** proposed scheme delivers a prominent visual quality despite high embedding *** tests carried out on over 100 natural image data sets and medical images show an improvement in results compared to the existing *** the algorithm is based on the variable radix number system,it is more resistant to most of the steganographic *** results were compared with a higher embedding capacity of up to 1.5 bpp reversible schemes for parameters like Peak Signal-to-Noise Ratio(PSNR),Embedding Capacity(EC)and Structural Similarity Index Metric(SSIM).

关键词： data hiding spatial correlation radix system prediction error embedding capacity

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A study on 3-d velocity structure of crust and upper mantle in Sichuan -Yunnan region, China

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Acta Seismologica Sinica(English Edition) 2002年第1期15卷 1-17页

作者：王椿镛 Mooney W.d 王溪莉吴建平楼海王飞 Institute of Geophysics China Seismological Bureau Beijing 100081 China U. S. Geological Survey Menlo Park CA94025 USA

Based on the first arrival P and S data of 4 625 regional earthquakes recorded at 174 stations dispersed in the Yunnan and Sichuan Provinces, the 3-d velocity structure of crust and upper mantle in the region is determined, incorporating with previous deep geophysical data. In the upper crust, a positive anomaly velocity zone exists in the Sichuan basin, whereas a negative anomaly velocity zone exists in the western Sichuan plateau. The boundary between the positive and negative anomaly zones is the Longmenshan fault zone. The images of lower crust and upper mantle in the Longmenshan fault, Xianshuihe fault, Honghe fault and others show the characteristic of tectonic boundary, indicating that the faults likely penetrate the Moho discontinuity. The negative velocity anomalies at the depth of 50 km in the Tengchong volcanic area and the Panxi tectonic zone appear to be associated with the temperature and composition variations in the upper mantle. The overall features of the crustal and the upper mantle structures in the SichuanYunnan region are the lower average velocity in both crust and uppermost mantle, the large crustal thickness variations, and the existence of high conductivity layer in the crust or/and upper mantle, and higher geothermal value. All these features are closely related to the collision between the India and the Asia plates. The crustal velocity in the SichuanYunnan rhombic block generally shows normal value or positive anomaly, while the negative anomaly exists in the area along the large strike-slip faults as the block boundary. It is conducive to the crustal block side-pressing out along the faults. In the major seismic zones, the seismicity is relative to the negative anomaly velocity. Most strong earthquakes occurred in the upper-mid crust with positive anomaly or normal velocity, where the negative anomaly zone generally exists below.

关键词： regional earthquake Moho discontinuity 3-d velocity structure network method plate collision seismicity

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老钢桥剩余安全度与剩余寿命估计

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同济大学学报（自然科学版） 2001年第4期29卷 384-389页

作者：陈惟珍 G.Albrecht d.Kosteas 同济大学桥梁工程系上海200092 慕尼黑工业大学土木系

通过对老钢桥疲劳断裂安全度的分析 ,计算了老钢桥的剩余寿命和继续使用所需的检测间隔 ,为老钢桥在考虑经济性前提下的维修与加固提供了可靠性依据 .

关键词：老钢桥剩余安全度检测间隔剩余寿命疲劳断裂破坏概率寿命估计

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A double Swath Configuration for Improving Throughput and Accuracy of Trait Estimate from UAV Images

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Plant Phenomics 2021年第1期3卷 378-388页

作者： Wenjuan Li Alexis Comar Marie Weiss Sylvain Jay Gallian Colombeau Raul Lopez-Lozano Simon Madec Frédéric Baret HIPHEN 228 Route de l’Aérodrome84000 AvignonFrance INRAE Avignon UniversitéUMR EMMAH84000 AvignonFrance ARVALIS Institut du Végétal 3 Rue Joseph et Marie Hackin75116 ParisFrance

Multispectral observations from unmanned aerial vehicles(UAVs)are currently used for precision agriculture and crop phenotyping applications to monitor a series of traits allowing the characterization of the vegetation ***,the limited autonomy of UAVs makes the completion of flights difficult when sampling large *** the throughput of data acquisition while not degrading the ground sample distance(GSd)is,therefore,a critical issue to be *** propose here a new image acquisition configuration based on the combination of two focal length(f)optics:an optics with f=4:2 mm is added to the standard f=8 mm(SS:single swath)of the multispectral camera(dS:double swath,double of the standard one).Two flights were completed consecutively in 2018 over a maize field using the AIRPHEN multispectral camera at 52 m *** dS flight plan was designed to get 80%overlap with the 4.2 mm optics,while the SS one was designed to get 80%overlap with the 8 mm *** a result,the time required to cover the same area is halved for the dS as compared to the *** georeferencing accuracy was improved for the dS configuration,particularly for the Z dimension due to the larger view angles available with the small focal length *** to plant height estimates demonstrates that the dS configuration provides similar results as the SS ***,for both the dS and SS configurations,degrading the quality level used to generate the 3d point cloud significantly decreases the plant height estimates.

关键词： optics overlap altitude

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Residues of Polychlorinated Biphenyls (PCBs) in Fish, Water and Sediment from Shing Mun River

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Biomedical and Environmental Sciences 1991年第4期4卷 399-408页

作者： V.W.d.CHUI T.C.CHAN S.Y.LAM-LEUNG department of Biology Hong Kong Baptist College 224 Waterloo Road Kowloon Hong KongDepartment of Biology Hong Kong Baptist College 224 Waterloo Road Kowloon Hong KongDepartment of Chemistry Hong Kong Baptist College 224 Waterloo Road Kowloon Hong Kong

The level and pattern of contamination by polychlorinated biphenyls (PCBs) were investigated in tilapia, Oreochromis mossambicus (Peters), sediment, and water from the Shing Mun River. The range of total PCBs was 12.9 ng/g to 181.6 ng/g wet weight in tilapia, 12.7 ng/g to 46.0 ng/g freeze-dried weight in sediment, and 3.8 ng/L to 13.6 ng/L in water. The effect of biomagnification was also observed, PCB concentrations increased from water to sediment to tilapia. PCB congeners occurred in such a way that lower chlorinated PCBs comprised a higher fraction of the total PCBs in water, sediment, and tilapia muscle, whereas higher chlorinated PCBs were more commonly found only in tilapia.

关键词： PCBs Residues of Polychlorinated Biphenyls Water and Sediment from Shing Mun River in Fish

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Coupling the porous conditional moment closure with the random pore model： applications to gasification and C02 capture

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Frontiers of Chemical Science and Engineering 2012年第1期6卷 84-93页

作者： d. N. SAULOV C. R. CHOdANKA M. J. CLEARY A. Y. KLIMENKO School of Mechanical and Mining Engineering the University of Queensland Brisbane 4072 Australia

Gasification of coal or biomass with in situ CO2 capture simultaneously allows production of clean hydrogen at relatively low cost and reduced emission of CO2 into the atmosphere. Clearly, this technology has a great potential for a future carbon constrained economy. Therefore, the development of a comprehensive, physically-based gasifier model is important. The sub- models that describe reactive transport processes in coal particles as well as in particles of CO2 sorbent material are among the key sub-models, which provide a necessary input for an overall gasifier model. Both coal and sorbent are materials that have complicated pore structures. The porous conditional moment closure （PCMC） model proves to be adequate for modeling reactive transport through porous media with fixed pore structure. Consumption of coal in the heterogeneous gasification reaction, however, widens the pores and reduces the surface area available for this reaction. At the same time, formation of a carbonate layer narrows the pores in the sorbent material and reduces the reaction rate of CO2 sorption. In both cases the pore structures are affected. Such changes are not taken into account in the existing PCMC model. In this study, we obtain the parameters of the diffusive tracer distribution based on the pore size distribution given by the widely applied random pore model （RPM）, while coupling PCMC with RPM. Such coupling allows taking into account changes in pore structure caused by heterogeneous reactions and thus improves the accuracy of these key sub-models.

关键词： gasification CO2 capture PCMC RPM

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Modeling fire ignition probability and frequency using Hurdle models: a crossregional study in Southern Europe

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Ecological Processes 2020年第1期9卷 634-647页

作者： Marina d’Este Antonio Ganga Mario Elia Raffaella Lovreglio Vincenzo Giannico Giuseppina Spano Giuseppe Colangelo Raffaele Lafortezza Giovanni Sanesi department of Agricultural and Environmental Sciences University of Bari A.MoroVia Amendola 165/A70126 BariItaly department of Agriculture University of SassariViale Italia 3907100 SassariItaly department of Geography The University of Hong KongCentennial CampusPokfulam RoadPok Fu LamHong Kong

Background:Wildfires play a key role in shaping Mediterranean landscapes and ecosystems and in impacting species *** studies have investigated the wildfire occurrences and the influence of their drivers in many countries of the Mediterranean ***,in this regard,no studies have attempted to compare different Mediterranean regions,which may appear similar under many *** response to this gap,climatic,topographic,anthropic,and landscape drivers were analyzed and compared to assess the patterns of fire ignition points in terms of fire occurrence and frequency in Catalonia(Spain),Sardinia,and Apulia(Italy).Therefore,the objectives of the study were to(1)assess fire ignition occurrence in terms of probability and frequency,(2)compare the main drivers affecting fire occurrence,and(3)produce fire probability and frequency maps for each ***:In pursuit of the above,the probability of fire ignition occurrence and frequency was mapped using Negative Binomial Hurdle models,while the models’performances were evaluated using several metrics(AUC,prediction accuracy,RMSE,and the Pearson correlation coefficient).The results showed an inverse correlation between distance from infrastructures(i.e.,urban roads and areas)and the occurrence of fires in all three study *** relationship became more significant when the frequency of fire ignition points was ***,a positive correlation was found between fire occurrence and landscape drivers according to *** land cover classes more significantly affected were forest,agriculture,and grassland for Catalonia,Sardinia,and Apulia,***:Compared to the climatic,topographic,and landscape drivers,anthropic activity significantly influences fire ignition and frequency in all three *** the distance from urban roads and areas decreases,the probability of fire ignition occurrence and frequency ***,it is essential to implement long-to medium-

关键词： driving factor Fire frequency Fire management Fire occurrence Hurdle models Mediterranean Basin Wildfires

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Gyro-Chirality Effect of Bianisotropic Substrate on the Resonant Frequency and Half-power Bandwidth of Rectangular Microstrip Patch Antenna

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Computers, Materials & Continua 2016年第5期52卷 123-131页

作者： C.Zebiri d.Sayad S.daoudi F.Benabdelaziz M.Lashab R.A.Abd-Alhameed Electronics department University Ferhat Abbas of SETIF-1-19000 SETIFALGERIA Electronics department University 20 Aout 195521000 SKIKDAALGERIA Electronics department University Mentouri of Constantine-1-25000 CONSTANTINEALGERIA School of Electrical Engineering and Computer Science University of BradfordBD71DPUK

In this paper,the gyrotropic bi-anisotropy of the chiral medium in substrate constitutive parameters(xc and hc)of a rectangular microstrip patch antenna is introduced in order to observe its effects on the complex resonant frequency and half-power *** analysis is based on the full-wave spectral domain approach using the Moment Method,with sinusoidal type basis *** numerical calculations related to the dominant mode have been carried out,and it has been observed that the resonant frequency and the bandwidth are directly linked to the medium *** new results can be considered as a generalisation form of the previously published work.

关键词： Microstrip antenna Chiral Gyrotropy Bi-anisotropy Moment Method

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Metabolic Engineering of Plant-derived (E)-β-farnesene Synthase Genes for a Novel Type of Aphid-resistant Genetically Modified Crop Plants

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Journal of Integrative Plant Biology 2012年第5期54卷 282-299页

作者： Xiu-dao Yu John Pickett You-Zhi Ma Toby Bruce Johnathan Napier Huw d.Jones Lan-Qin Xia Institute of Crop Sciences(ICS) Chinese Academy of Agricultural Sciences(CAAS)Beijing 100081China Rothamsted Research HarpendenHertfordshire AL52JQUK

Aphids are major agricultural pests that cause significant yield losses of crop plants each year. Excessive dependence on insec- ticides for long-term aphid control is undesirable because of the development of insecticide resistance, the potential negative effects on non-target organisms and environmental pollution. Transgenic crops engineered for resistance to aphids via a non-toxic mode of action could be an efficient alternative strategy. （E）-β-Farnesene （EβF） synthases catalyze the formation of EβF, which for many pest aphids is the main component of the alarm pheromone involved in the chemical communication within these species. EβF can also be synthesized by certain plants but is then normally contaminated with inhibitory compounds. Engineering of crop plants capable ofsynthesizing and emitting EβF could cause repulsion of aphids and also the attraction of natural enemies that use EβF as a foraging cue, thus minimizing aphid infestation. In this review, the effects of aphids on host plants, plants＇ defenses against aphid herbivory and the recruitment of natural enemies for aphid control in an agricultural setting are briefly introduced. Furthermore, the plant-derived EβF synthase genes cloned to date along with their potential roles in generating novel aphid resistance via genetically modified approaches are discussed.

关键词： Aphids (E)-β-farnesene sythase genetic-modified crops terpenoid.

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Characteristics of ^(137)Cs deposition in steppe area

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Chinese Science Bulletin 2002年第10期47卷 848-853页

作者： ZHANG Chunlai, ZOU Xueyong,dONG Guangrong, ZHANG Xinbao & QIN ZhiLaboratory of Blown Sand Physics and Engineering, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China China Center of d Laboratory of Blown Sand Physics and Engineering Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China China Center of desert Research at Beijing Normal University Key Laboratory of Environmental Change and Natural Disaster of the Ministry of Education of China Beijing Normal University Beijing China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China Institute of Modern Physics Chinese Academy of Sciences Lanzhou China

Soil wind erosion in the semiarid steppe area was studied using the 137Cs tracing technique. Comparisons of 137Cs deposition characteristics between different soil profiles indicated that slight aeolian activities occurred on sandy grasslands and semi-fixed dunes with erosion/deposition rates of less than 0.108 cm/a, whereas they were intense on semi-shifting dunes with erosion/deposition rates of higher than 1.35 cm/a.

关键词： 137Cs steppe soil wind erosion.

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