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ESMD Method for Frequency Distribution of Tank Surface Temperature under Wind Effect
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作者 Jinliang Wang Xianshui Fang 《International Journal of Geosciences》 2015年第5期481-486,共6页
Due to the poor understanding of the small-scale processes at the air-water interface, some lab experiments are done in a water tank by infrared techniques. With the help of ESMD method, the stochastic temperature seq... Due to the poor understanding of the small-scale processes at the air-water interface, some lab experiments are done in a water tank by infrared techniques. With the help of ESMD method, the stochastic temperature sequences extracted from the infrared photographs are decomposed into several empirical modes of general periodic forms. The corresponding analyses on the modes reveal that, within certain limits, both spatial and temporal frequencies increase along the wind speed. As for the amplitudes, the existence of wind may result in fold increasing of their values. In addition, when the wind speed is added from 4 m/s to 5 m/s, both frequency and amplitude of the surface temperature decrease and it implies an enhanced mixing and a weakened temperature gradient under the force of wind blowing. 展开更多
关键词 Extreme-Point SYMMETRIC Mode DECOMPOSITION (ESMD) Surface Temperature TIME-frequency distribution WIND Wave TANK Experiment
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Cyberattack Ramifications, The Hidden Cost of a Security Breach
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作者 Meysam Tahmasebi 《Journal of Information Security》 2024年第2期87-105,共19页
In this in-depth exploration, I delve into the complex implications and costs of cybersecurity breaches. Venturing beyond just the immediate repercussions, the research unearths both the overt and concealed long-term ... In this in-depth exploration, I delve into the complex implications and costs of cybersecurity breaches. Venturing beyond just the immediate repercussions, the research unearths both the overt and concealed long-term consequences that businesses encounter. This study integrates findings from various research, including quantitative reports, drawing upon real-world incidents faced by both small and large enterprises. This investigation emphasizes the profound intangible costs, such as trade name devaluation and potential damage to brand reputation, which can persist long after the breach. By collating insights from industry experts and a myriad of research, the study provides a comprehensive perspective on the profound, multi-dimensional impacts of cybersecurity incidents. The overarching aim is to underscore the often-underestimated scope and depth of these breaches, emphasizing the entire timeline post-incident and the urgent need for fortified preventative and reactive measures in the digital domain. 展开更多
关键词 Artificial Intelligence (AI) Business Continuity Case Studies Copyright Cost-Benefit Analysis Credit Rating Cyberwarfare Cybersecurity Breaches Data Breaches Denial Of Service (DOS) Devaluation Of Trade Name Disaster Recovery Distributed Denial of Service (DDOS) Identity Theft Increased Cost to Raise Debt Insurance Premium Intellectual Property Operational Disruption Patent Post-Breach Customer Protection Recovery Point Objective (RPO) Recovery Time Objective (RTO) Regulatory Compliance Risk Assessment Service Level Agreement Stuxnet Trade Secret
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A VERIFICATION ON DIVISION OF HYDROCLIMATIC AREA IN CHINA SEAS USING DIGITAL CHARACTERISTIC OF FREQUENCY DISTRIBUTION
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作者 Chen Shangji Li Binglan Yao Shiyu Du Bing National Marine Data and Information Service, SOA, Tianjin 300171 People’s Republic of China 《Journal of Geographical Sciences》 SCIE CSCD 1997年第3期83-90,共8页
oceanographic data files on the China Seas prepared by the National Marine Data and Information Service, SOA, China and the '30-year (1953-1982) Reports of Sea Surface Monthly Mean Temperature in the East China Se... oceanographic data files on the China Seas prepared by the National Marine Data and Information Service, SOA, China and the '30-year (1953-1982) Reports of Sea Surface Monthly Mean Temperature in the East China Sea by the Meteorological Agency, Japan,' were used to calculate the digital characteristics of frequency distribution of sea and air temperature in 153 areas in the China Seas. Principal factor analysis and fuzzy cluster ISODATA were used to divide the China hydroclimatic area into three climatic zones including ten climatic regions. It is concluded that the characteristic values derived by this method may completely show the characteristics of frequency distribution of sea and air temperature in the studied area and the final division of hydroclimatic area is fully coincident with the author's former result [2]. 展开更多
关键词 China Seas division of marine hydroclimatic area digital characteristic of frequency distribution principal factor analysis fuzzy cluster ISODATA.
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Hierarchical microstructures with high spatial frequency laser induced periodic surface structures possessing different orientations created by femtosecond laser ablation of silicon in liquids 被引量:17
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作者 Dongshi Zhang Koji Sugioka 《Opto-Electronic Advances》 2019年第3期1-18,共18页
High spatial frequency laser induced periodic surface structures(HSFLs)on silicon substrates are often developed on flat surfaces at low fluences near ablation threshold of 0.1 J/cm2,seldom on microstructures or micro... High spatial frequency laser induced periodic surface structures(HSFLs)on silicon substrates are often developed on flat surfaces at low fluences near ablation threshold of 0.1 J/cm2,seldom on microstructures or microgrooves at relatively higher fluences above 1 J/cm^2.This work aims to enrich the variety of HSFLs-containing hierarchical microstructures,by femtosecond laser(pulse duration:457 fs,wavelength:1045 nm,and repetition rate:100 kHz)in liquids(water and acetone)at laser fluence of 1.7 J/cm^2.The period of Si-HSFLs in the range of 110–200 nm is independent of the scanning speeds(0.1,0.5,1 and 2 mm/s),line intervals(5,15 and 20μm)of scanning lines and scanning directions(perpendicular or parallel to light polarization direction).It is interestingly found that besides normal HSFLs whose orientations are perpendicular to the direction of light polarization,both clockwise or anticlockwise randomly tilted HSFLs with a maximal deviation angle of 50°as compared to those of normal HSFLSs are found on the microstructures with height gradients.Raman spectra and SEM characterization jointly clarify that surface melting and nanocapillary waves play important roles in the formation of Si-HSFLs.The fact that no HSFLs are produced by laser ablation in air indicates that moderate melting facilitated with ultrafast liquid cooling is beneficial for the formation of HSFLs by LALs.On the basis of our findings and previous reports,a synergistic formation mechanism for HSFLs at high fluence was proposed and discussed,including thermal melting with the concomitance of ultrafast cooling in liquids,transformation of the molten layers into ripples and nanotips by surface plasmon polaritons(SPP)and second-harmonic generation(SHG),and modulation of Si-HSFLs direction by both nanocapillary waves and the localized electric field coming from the excited large Si particles. 展开更多
关键词 HIGH spatial frequency LASER induced periodic SURFACE structures SILICON LASER ablation in liquids HIERARCHICAL MICROSTRUCTURES femtosecond LASER HIGH fluence formation mechanism SURFACE melting nanocapillary wave SURFACE plasmon polaritons second-harmonic generation
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Analysis of DAR(1)/D/s Queue with Quasi-Negative Binomial-II as Marginal Distribution
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作者 Kanichukattu Korakutty Jose Bindu Abraham 《Applied Mathematics》 2011年第9期1159-1169,共11页
In this paper we consider the arrival process of a multiserver queue governed by a discrete autoregressive process of order 1 [DAR(1)] with Quasi-Negative Binomial Distribution-II as the marginal distribution. This di... In this paper we consider the arrival process of a multiserver queue governed by a discrete autoregressive process of order 1 [DAR(1)] with Quasi-Negative Binomial Distribution-II as the marginal distribution. This discrete time multiserver queueing system with autoregressive arrivals is more suitable for modeling the Asynchronous Transfer Mode(ATM) multiplexer queue with Variable Bit Rate (VBR) coded teleconference traffic. DAR(1) is described by a few parameters and it is easy to match the probability distribution and the decay rate of the autocorrelation function with those of measured real traffic. For this queueing system we obtained the stationary distribution of the system size and the waiting time distribution of an arbitrary packet with the help of matrix analytic methods and the theory of Markov regenerative processes. Also we consider negative binomial distribution, generalized Poisson distribution, Borel-Tanner distribution defined by Frank and Melvin(1960) and zero truncated generalized Poisson distribution as the special cases of Quasi-Negative Binomial Distribution-II. Finally, we developed computer programmes for the simulation and empirical study of the effect of autocorrelation function of input traffic on the stationary distribution of the system size as well as waiting time of an arbitrary packet. The model is applied to a real data of number of customers waiting for checkout in an airport and it is established that the model well suits this data. 展开更多
关键词 Discrete Autoregressive PROCESS of Order [DAR(1)] Multiserver ATM Multiplexer Matrix Analytic Methods MARKOV Renewal PROCESS MARKOV Regenerative Theory Teleconference Traffic Quasi-Negative BINOMIAL distribution-II Generalized Poisson distribution Borel-Tanner distribution
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Adaptive Time Frequency Distribution Based on Linear Chirp Modulated Gaussian Functions 被引量:3
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作者 Shi-wei Ma Guang-hua Chen +1 位作者 Jia-mei Deng Jia-lin Cao 《Advances in Manufacturing》 2000年第1期31-37,共7页
We propose a method that uses linear chirp modulated Gaussian functions as the elementary functions, by adaptively adjusting variances, time frequency centers and sweep rates, to decompose signals. By taking WVD, an ... We propose a method that uses linear chirp modulated Gaussian functions as the elementary functions, by adaptively adjusting variances, time frequency centers and sweep rates, to decompose signals. By taking WVD, an improved adaptive time frequency distribution is developed, which is non negative, free of cross term interference, and of better time frequency resolution. The paper presents an effective numerical algorithm to estimate the optimal parameters of the basis. Simulations indicate that the proposed approach is effective in analyzing signal's time frequency behavior. 展开更多
关键词 adaptive time frequency distribution elementary function subspace decomposition STFT WVD
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Prevalence and ecological factors affecting the distribution of plant-parasitic nematodes in Prunus groves in Spain
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作者 Ilenia Clavero-Camacho Antonio Archidona-Yuste +2 位作者 Carolina Cantalapiedra-Navarrete Pablo Castillo Juan Emilio Palomares-Rius 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期566-589,共24页
A wide survey was conducted to study plant-parasitic nematodes(PPNs)associated with Prunus groves in Spain.This research aimed to determine the prevalence and distribution of PPNs in Prunus groves,as well as the influ... A wide survey was conducted to study plant-parasitic nematodes(PPNs)associated with Prunus groves in Spain.This research aimed to determine the prevalence and distribution of PPNs in Prunus groves,as well as the influence of explanatory variables describing soil,climate and agricultural management in structuring the variation of PPNs community composition.A total of 218 sampling sites were surveyed and 84 PPN species belonging to 32 genera were identified based of an integrative taxonomic approach.PPN species considered as potential limiting factors in Prunus production,such as Meloidogyne arenaria,M.incognita,M.javanica,Pratylenchus penetrans and P.vulnus,were identified in this survey.Seven soil physico-chemical(C,Mg,N,Na,OM,P,pH and clay,loamy sand and sandy loam texture classes),four climate(Bio04,Bio05,Bio13 and Bio14)and four agricultural management variables(grove-use history less than 10 years,irrigation,apricot seedling rootstock,and Montclar rootstock)were identified as the most influential variables driving spatial patterns of PPNs communities.In particular,younger plantations showed higher values for species richness and diversity indices than groves cultivated for more than 20 years with Prunus spp.Our study increases the knowledge of the distribution and prevalence of PPNs associated with Prunus rhizosphere,as well as on the influence of explanatory variables driving the spatial structure PPNs communities,which has important implications for the successful design of sustainable management strategies in the future in this agricultural system. 展开更多
关键词 nematodes MELOIDOGYNE PRATYLENCHUS Paratylenchus ROOTSTOCK distribution soil grove-use ALMOND peach
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Likelihood and Quadratic Distance Methods for the Generalized Asymmetric Laplace Distribution for Financial Data 被引量:1
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作者 Andrew Luong 《Open Journal of Statistics》 2017年第2期347-368,共22页
Maximum likelihood (ML) estimation for the generalized asymmetric Laplace (GAL) distribution also known as Variance gamma using simplex direct search algorithms is investigated. In this paper, we use numerical direct ... Maximum likelihood (ML) estimation for the generalized asymmetric Laplace (GAL) distribution also known as Variance gamma using simplex direct search algorithms is investigated. In this paper, we use numerical direct search techniques for maximizing the log-likelihood to obtain ML estimators instead of using the traditional EM algorithm. The density function of the GAL is only continuous but not differentiable with respect to the parameters and the appearance of the Bessel function in the density make it difficult to obtain the asymptotic covariance matrix for the entire GAL family. Using M-estimation theory, the properties of the ML estimators are investigated in this paper. The ML estimators are shown to be consistent for the GAL family and their asymptotic normality can only be guaranteed for the asymmetric Laplace (AL) family. The asymptotic covariance matrix is obtained for the AL family and it completes the results obtained previously in the literature. For the general GAL model, alternative methods of inferences based on quadratic distances (QD) are proposed. The QD methods appear to be overall more efficient than likelihood methods infinite samples using sample sizes n ≤5000 and the range of parameters often encountered for financial data. The proposed methods only require that the moment generating function of the parametric model exists and has a closed form expression and can be used for other models. 展开更多
关键词 M-ESTIMATORS CUMULANT Generating Function CHI-SQUARE Tests Generalized Hyperbolic distribution Simplex Pattern Search Variance Gamma Minimum Distance VALUE at RISK Entropic VALUE at RISK European Call Option
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Binary Gravitational Search based Algorithm for Optimum Siting and Sizing of DG and Shunt Capacitors in Radial Distribution Systems
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作者 N. A. Khan S. Ghosh S. P. Ghoshal 《Energy and Power Engineering》 2013年第4期1005-1010,共6页
This paper presents a binary gravitational search algorithm (BGSA) is applied to solve the problem of optimal allotment of DG sets and Shunt capacitors in radial distribution systems. The problem is formulated as a no... This paper presents a binary gravitational search algorithm (BGSA) is applied to solve the problem of optimal allotment of DG sets and Shunt capacitors in radial distribution systems. The problem is formulated as a nonlinear constrained single-objective optimization problem where the total line loss (TLL) and the total voltage deviations (TVD) are to be minimized separately by incorporating optimal placement of DG units and shunt capacitors with constraints which include limits on voltage, sizes of installed capacitors and DG. This BGSA is applied on the balanced IEEE 10 Bus distribution network and the results are compared with conventional binary particle swarm optimization. 展开更多
关键词 Normal Load Flow Radial distribution System Distributed Generation SHUNT Capacitors BINARY Particle SWARM Optimization BINARY GRAVITATIONAL SEARCH Algorithm TOTAL line Loss TOTAL Voltage Deviation
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Optimal Partitioning of Distribution Networks for Micro-Grid Operation
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作者 Shane J. Kimble Divya T. Vedullapalli Elham B. Makram 《Journal of Power and Energy Engineering》 2017年第9期104-120,共17页
A great concern for the modern distribution grid is how well it can withstand and respond to adverse conditions. One way that utilities are addressing this issue is by adding redundancy to their systems. Likewise, dis... A great concern for the modern distribution grid is how well it can withstand and respond to adverse conditions. One way that utilities are addressing this issue is by adding redundancy to their systems. Likewise, distributed generation (DG) is becoming an increasingly popular asset at the distribution level and the idea of microgrids operating as standalone systems apart from the bulk electric grid is quickly becoming a reality. This allows for greater flexibility as systems can now take on exponentially more configurations than the radial, one-way distribution systems of the past. These added capabilities, however, make the system reconfiguration with a much more complex problem causing utilities to question if they are operating their distribution systems optimally. In addition, tools like Supervisory Control and Data Acquisition (SCADA) and Distribution Automation (DA) allow for systems to be reconfigured faster than humans can make decisions on how to reconfigure them. As a result, this paper seeks to develop an automated partitioning scheme for distribution systems that can respond to varying system conditions while ensuring a variety of operational constraints on the final configuration. It uses linear programming and graph theory. Power flow is calculated externally to the LP and a feedback loop is used to recalculate the solution if a violation is found. Application to test systems shows that it can reconfigure systems containing any number of loops resulting in a radial configuration. It can connect multiple sources to a single microgrid if more capacity is needed to supply the microgrid’s load. 展开更多
关键词 Distributed Generation (DG) Supervisory Control and Data ACQUISITION (SCADA) distribution Automation (DA) FAULT Location Isolation and RESTORATION (FLISR) SELF-HEALING Network MICRO-GRID Smart Grid
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A tunable passive mixer for SAW-less front-end with reconfigurable voltage conversion gain and intermediate frequency bandwidth 被引量:1
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作者 陶健 fan xiangning zhao yuan 《High Technology Letters》 EI CAS 2018年第1期10-18,共9页
An adjustable mixer for surface acoustic wave( SAW)-less radio frequency( RF) front-end is presented in this paper. Through changing the bias voltage,the presented mixer with reconfigurable voltage conversion gain( VC... An adjustable mixer for surface acoustic wave( SAW)-less radio frequency( RF) front-end is presented in this paper. Through changing the bias voltage,the presented mixer with reconfigurable voltage conversion gain( VCG) is suitable for multi-mode multi-standard( MMMS) applications. An equivalent local oscillator( LO) frequency-tunable high-Q band-pass filter( BPF) at low noise amplifier( LNA) output is used to reject the out-of-band interference signals. Base-band( BB) capacitor of the mixer is variable to obtain 15 kinds of intermediate frequency( IF) bandwidth( BW). The proposed passive mixer with LNA is implemented in TSMC 0. 18μm RF CMOS process and operates from 0. 5 to 2. 5 GHz with measured maximum out-of-band rejection larger than 40 d B. The measured VCG of the front-end can be changed from 5 to 17 d B; the maximum input intercept point( IIP3) is0 d Bm and the minimum noise figure( NF) is 3. 7 d B. The chip occupies an area of 0. 44 mm^2 including pads. 展开更多
关键词 RECONFIGURABLE radio frequency (RF) FRONT-END multi-mode multi-standard( MMMS) HIGH-Q BAND-PASS filter ( BPF) cross-coupled common gate low noise amplifier ( CC-CGLNA) CMOS
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Prognostic value of red blood cell distribution width for severe acute pancreatitis 被引量:50
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作者 Fang-Xiao Zhang Zhi-Liang Li +1 位作者 Zhi-Dan Zhang Xiao-Chun Ma 《World Journal of Gastroenterology》 SCIE CAS 2019年第32期4739-4748,共10页
BACKGROUND Severe acute pancreatitis(SAP)is a common condition in the intensive care unit(ICU)and has a high mortality.Early evaluation of the severity and prognosis is very important for SAP therapy.Recently,red bloo... BACKGROUND Severe acute pancreatitis(SAP)is a common condition in the intensive care unit(ICU)and has a high mortality.Early evaluation of the severity and prognosis is very important for SAP therapy.Recently,red blood cell distribution(RDW)was associated with mortality of sepsis patients and could be used as a predictor of prognosis.Similarly,RDW may be associated with the prognosis of SAP patients and be used as a prognostic indicator for SAP patients.AIM To investigate the prognostic value of RDW for SAP patients.METHODS We retrospectively enrolled SAP patients admitted to the ICU of the First Affiliated Hospital of China Medical University from June 2015 to June 2017.According to the prognosis at 90 d,SAP patients were divided into a survival group and a non-survival group.RDW was extracted from a routine blood test.Demographic parameters and RDW were recorded and compared between the two groups.The receiver operator characteristic(ROC)curve was constructed and Cox regression analysis was performed to investigate the prognostic value of RDW for SAP patients.RESULTS In this retrospective cohort study,42 SAP patients were enrolled,of whom 22 survived(survival group)and 20 died(non-survival group).The baseline parameters were comparable between the two groups.The coefficient of variation of RDW(RDW-CV),standard deviation of RDW(RDW-SD),Acute Physiology and Chronic Health Evaluation II(APACHE II)score,and Sequential Organ Failure Assessment(SOFA)score were significantly higher in the non-survival group than in the survival group(P<0.05).The RDW-CV and RDW-SD were significantly correlated with the APACHE II score and SOFA score,respectively.The areas under the ROC curves(AUCs)of RDW-CV and RDW-SD were all greater than those of the APACHE II score and SOFA score,among which,the AUC of RDW-SD was the greatest.The results demonstrated that RDW had better prognostic value for predicting the mortality of SAP patients.When the RDW-SD was greater than 45.5,the sensitivity for predicting prognosis was 77.8%and the specificity was 70.8%.Both RDW-CV and RDW-SD could be used as independent risk factors to predict the mortality of SAP patients in multivariate logistic regression analysis and univariate Cox proportional hazards regression analysis,similar to the APACHE II and SOFA scores.CONCLUSION The RDW is greater in the non-surviving SAP patients than in the surviving patients.RDW is significantly correlated with the APACHE II and SOFA scores.RDW has better prognostic value for SAP patients than the APACHE II and SOFA scores and could easily be used by clinicians for the treatment of SAP patients. 展开更多
关键词 Red blood cell distribution WIDTH Severe ACUTE PANCREATITIS Prognosis ACUTE PHYSIOLOGY and Chronic Health Evaluation SCORE Sequential ORGAN Failure Assessment SCORE
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The Chapman-Richards Distribution and its Relationship to the Generalized Beta
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作者 Jeffrey H.Gove Thomas B.Lynch Mark J.Ducey 《Forest Ecosystems》 SCIE CSCD 2019年第3期219-235,共17页
Background: The Chapman-Richards distribution is developed as a special case of the equilibrium solution to the McKendrick-Von Foerster equation. The Chapman-Richards distribution incorporates the vital rate assumptio... Background: The Chapman-Richards distribution is developed as a special case of the equilibrium solution to the McKendrick-Von Foerster equation. The Chapman-Richards distribution incorporates the vital rate assumptions of the Chapman-Richards growth function, constant mortality and recruitment into the mathematical form of the distribution. Therefore, unlike 'assumed' distribution models, it is intrinsically linked with the underlying vital rates for the forest area under consideration. Methods: It is shown that the Chapman-Richards distribution can be recast as a subset of the generalized beta distribution of the first kind, a rich family of assumed probability distribution models with known properties. These known properties for the generalized beta are then immediately available for the Chapman-Richards distribution, such as the form of the compatible basal area-size distribution. A simple two-stage procedure is proposed for the estimation of the model parameters and simulation experiments are conducted to validate the procedure for four different possible distribution shapes. Results: The simulations explore the efficacy of the two-stage estimation procedure;these cover the estimation of the growth equation and mortality-recruitment derives from the equilibrium assumption. The parameter estimates are shown to depend on both the sample size and the amount of noise imparted to the synthetic measurements. The results vary somewhat by distribution shape, with the smaller, noisier samples providing less reliable estimates of the vital rates and final distribution forms. Conclusions: The Chapman-Richards distribution in its original form, or recast as a generalized beta form, presents a potentially useful model integrating vital rates and stand diameters into a flexible family of resultant distributions shapes. The data requirements are modest, and parameter estimation is straightforward provided the minimal recommended sample sizes are obtained. 展开更多
关键词 Diameter distributionS Chapman-Richards growth Generalized BETA distribution of the first kind Maximum LIKELIHOOD McKendrick-Von Foerster equation Physiologically STRUCTURED population model Size-structured distributionS
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Identification and distribution of 13003 landslides in the northwest margin of Qinghai-Tibet Plateau based on human-computer interaction remote sensing interpretation
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作者 Wei Wang Yuan-dong Huang +8 位作者 Chong Xu Xiao-yi Shao Lei Li Li-ye Feng Hui-ran Gao Yu-long Cui Shuai Wu Zhi-qiang Yang Kai Ma 《China Geology》 CAS CSCD 2024年第2期171-187,共17页
The periphery of the Qinghai-Tibet Plateau is renowned for its susceptibility to landslides.However,the northwestern margin of this region,characterised by limited human activities and challenging transportation,remai... The periphery of the Qinghai-Tibet Plateau is renowned for its susceptibility to landslides.However,the northwestern margin of this region,characterised by limited human activities and challenging transportation,remains insufficiently explored concerning landslide occurrence and dispersion.With the planning and construction of the Xinjiang-Tibet Railway,a comprehensive investigation into disastrous landslides in this area is essential for effective disaster preparedness and mitigation strategies.By using the human-computer interaction interpretation approach,the authors established a landslide database encompassing 13003 landslides,collectively spanning an area of 3351.24 km^(2)(36°N-40°N,73°E-78°E).The database incorporates diverse topographical and environmental parameters,including regional elevation,slope angle,slope aspect,distance to faults,distance to roads,distance to rivers,annual precipitation,and stratum.The statistical characteristics of number and area of landslides,landslide number density(LND),and landslide area percentage(LAP)are analyzed.The authors found that a predominant concentration of landslide origins within high slope angle regions,with the highest incidence observed in intervals characterised by average slopes of 20°to 30°,maximum slope angle above 80°,along with orientations towards the north(N),northeast(NE),and southwest(SW).Additionally,elevations above 4.5 km,distance to rivers below 1 km,rainfall between 20-30 mm and 30-40 mm emerge as particularly susceptible to landslide development.The study area’s geological composition primarily comprises Mesozoic and Upper Paleozoic outcrops.Both fault and human engineering activities have different degrees of influence on landslide development.Furthermore,the significance of the landslide database,the relationship between landslide distribution and environmental factors,and the geometric and morphological characteristics of landslides are discussed.The landslide H/L ratios in the study area are mainly concentrated between 0.4 and 0.64.It means the landslides mobility in the region is relatively low,and the authors speculate that landslides in this region more possibly triggered by earthquakes or located in meizoseismal area. 展开更多
关键词 LANDSLIDES Human-computer interaction interpretation Landslide database Spatial distribution Earthquake RAINFALL Human engineering activity Qinghai-Tibet Plateau Geological hazards survey engineering
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Model of Universe as Described by Dynamic Universe Model
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作者 Satyavarapu Naga Parameswara Gupta 《Open Journal of Modelling and Simulation》 2019年第1期41-78,共38页
In this paper we will see the model of Universe according to Dynamic Universe Model of Cosmology by visualizing various processes that are happening in the Universe as per experimental evidences. For simplifying the m... In this paper we will see the model of Universe according to Dynamic Universe Model of Cosmology by visualizing various processes that are happening in the Universe as per experimental evidences. For simplifying the matter here, we will see in part 1: about the Galaxy life cycle, where the birth and death of Galaxies discussed. Probably Universe gives guidance for the movement of Galaxies. We call this Part 1: Thinking and Reproducing Universe or Mindless Universe? (Galaxy life cycle). We see every day Sun, Stars, Galaxies etc., dissipating enormous energy in the form of radiation by the way of fusion of Hydrogen to helium. So after sometime all the Hydrogen is spent and Universe will die, is it not? … Dynamic Universe Model says that the energy in the form of electromagnetic radiation passing grazingly near any gravitating mass changes in frequency and finally will convert into neutrinos (mass). Hence Dynamic Universe Model proposes another process where energy will be converted back into matter and the cycle energy to mass to energy continues, sustaining the Universe to maintain this present status for ever in this form something like a Steady state model without any expansion. This we will see in Part 2: Energy - Mass - Energy Cycle. After converting energy into mass “how various elements are formed and where they are formed?” will be next logical question. Dynamic Universe Model says that these various particles change into higher massive particles or may get bombarded into stars or planets and various elements are formed. Here we bifurcate the formation of elements into 6 processes. They are for Elementary particles and elements generated in frequency changing process, By Cosmic rays, By Small stars, By Large Stars, By Super Novae and Manmade elements By Neutron Stars. This we will discuss in Part 3: Nucleosynthesis. 展开更多
关键词 DYNAMIC UNIVERSE MODEL Hubble Space Telescope (HST) SITA Simulations (SITA-Simulation of Inter Intra Tautness Attraction Forces Used by DYNAMIC UNIVERSE Model) Singularity-Free COSMOLOGY Blue Shifted GALAXIES Red Shifted GALAXIES Grazing Radiation frequency Changes Formation of Elements NUCLEOSYNTHESIS DYNAMIC UNIVERSE MODEL Energy to Mass Conversion Methods: N-Body Simulations-Gravitation-Cosmology
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鸭瘟病毒弱毒株在免疫雏鸭体内的分布和排毒规律 被引量:18
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作者 程安春 汪铭书 +8 位作者 刘菲 宋涌 袁桂萍 韩晓英 徐超 廖永洪 文明 周伟光 贾仁勇 《中国兽医学报》 CAS CSCD 北大核心 2005年第3期231-233,258,共4页
鸭瘟病毒(DPV)弱毒Cha株经皮下、口服和滴鼻3种途径免疫1日龄雏鸭,应用聚合酶链反应(PCR)检测了病毒在体内分布和排毒规律。Cha株免疫雏鸭后,对血液、心、肝、脾、肺、肾、十二指肠、直肠、法氏囊、胸腺、胰腺、延脑、大脑、小脑、舌、... 鸭瘟病毒(DPV)弱毒Cha株经皮下、口服和滴鼻3种途径免疫1日龄雏鸭,应用聚合酶链反应(PCR)检测了病毒在体内分布和排毒规律。Cha株免疫雏鸭后,对血液、心、肝、脾、肺、肾、十二指肠、直肠、法氏囊、胸腺、胰腺、延脑、大脑、小脑、舌、肌肉、骨髓、粪便和食道共19种组织PCR检测结果如下(1)皮下接种雏鸭后4h,即可在心、肝、脾、肾、法氏囊、胸腺、胰腺、延脑、大脑和小脑共10种组织中检出DPV的DNA;8h后,所有采取的组织器官均可检测到DPV的DNA。(2)口服接种雏鸭后4h,可在舌和食道中检测到DPV的DNA;8h后,可在心、肝、脾、肾、胸腺、胰腺、延脑、大脑、小脑、舌、食道和血液共12种组织器官中检出DPV的DNA。(3)滴鼻接种雏鸭后4h,未能在各种组织中检出DPV的DNA;8h后,可在心、肝、脾、肾、胸腺、延脑、大脑、小脑、舌、食道和血液共11种组织中检测到DPV的DNA。(4)在3种免疫途径中,检出时间最早和检出率最高的组织器官为肝脏、脑(大脑、小脑和延脑);3种途径免疫的鸭,从免疫后12h至21d均能从所有采集的组织中检测出DPVDNA。 展开更多
关键词 DNA DPV Cha PCR 便
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Control of the Dust Vertical Distribution over Western Africa by Convection and Scavenging
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作者 H.Senghor R.Pilon +7 位作者 B.Diallo J.Escribano F.Hourdin J.Y.Grandpeix O.Boucher M.Gueye A.T.Gaye E.Machu 《Journal of Atmospheric Science Research》 2024年第1期19-39,共21页
Saharan dust represents more than 50%of the total desert dust emitted around the globe and its radiative effect significantly affects the atmospheric circulation at a continental scale.Previous studies on dust vertica... Saharan dust represents more than 50%of the total desert dust emitted around the globe and its radiative effect significantly affects the atmospheric circulation at a continental scale.Previous studies on dust vertical distribution and the Saharan Air Layer(SAL)showed some shortcomings that could be attributed to imperfect representation of the effects of deep convection and scavenging.The authors investigate here the role of deep convective transport and scavenging on the vertical distribution of mineral dust over Western Africa.Using multi-year(2006-2010)simulations performed with the variable-resolution(zoomed)version of the LMDZ climate model.Simulations are compared with aerosol amounts recorded by the Aerosol Robotic Network(AERONET)and with vertical profiles of the Cloud-Aerosol Lidar with Orthogonal Polarization(CALIOP)measurements.LMDZ allows a thorough examination of the respective roles of deep convective transport,convective and stratiform scavenging,boundary layer transport,and advection processes on the vertical mineral dust distribution over Western Africa.The comparison of simulated dust Aerosol Optical Depth(AOD)and distribution with measurements suggest that scavenging in deep convection and subsequent re-evaporation of dusty rainfall in the lower troposphere are critical processes for explaining the vertical distribution of desert dust.These processes play a key role in maintaining a well-defined dust layer with a sharp transition at the top of the SAL and in establishing the seasonal cycle of dust distribution.This vertical distribution is further reshaped offshore in the Inter-Tropical Convergence Zone(ITCZ)over the Atlantic Ocean by marine boundary layer turbulent and convective transport and wet deposition at the surface. 展开更多
关键词 DUST Vertical distribution Sahara SAHEL West Africa Climate model CONVECTION SCAVENGING ITCZ
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Frequency Synchronization in OFDM System
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作者 C. Geetha Priya A. M. Vasumathi 《Journal of Signal and Information Processing》 2013年第3期138-143,共6页
An accurate frequency synchronization method using the zadoff-chu (ZC) constant envelop preamble is analyzed, and a new preamble weighted by pseudo-noise sequence is used for orthogonal frequency division multiplexing... An accurate frequency synchronization method using the zadoff-chu (ZC) constant envelop preamble is analyzed, and a new preamble weighted by pseudo-noise sequence is used for orthogonal frequency division multiplexing (OFDM) systems. Using this method, frequency offset estimator range is greatly enlarged with no loss in accuracy. The range of the frequency estimation is ±30 of subcarrier spacing using ZC sequence as preamble. Simulations in the MATLAB for an AWGN channel show that the proposed method achieves superior performance to existing techniques in terms of frequency accuracy and range. 展开更多
关键词 Orthogonal frequency Division MULTIPLEXING (OFDM) Additive White Gaussian Noise (AWGN) Carrier frequency OFFSET (CFO) Constant Amplitude Zero Auto Correlation (CAZAC) Zadoff-Chu (ZC)
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Kautz Function Based Continuous-Time Model Predictive Controller for Load Frequency Control in a Multi-Area Power System
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作者 A.Parassuram P.Somasundaram 《Computer Modeling in Engineering & Sciences》 SCIE EI 2018年第11期169-187,共19页
A continuous-time Model Predictive Controller was proposed using Kautz function in order to improve the performance of Load Frequency Control(LFC).A dynamic model of an interconnected power system was used for Model P... A continuous-time Model Predictive Controller was proposed using Kautz function in order to improve the performance of Load Frequency Control(LFC).A dynamic model of an interconnected power system was used for Model Predictive Controller(MPC)design.MPC predicts the future trajectory of the dynamic model by calculating the optimal closed loop feedback gain matrix.In this paper,the optimal closed loop feedback gain matrix was calculated using Kautz function.Being an Orthonormal Basis Function(OBF),Kautz function has an advantage of solving complex pole-based nonlinear system.Genetic Algorithm(GA)was applied to optimally tune the Kautz function-based MPC.A constraint based on phase plane analysis was implemented with the cost function in order to improve the robustness of the Kautz function-based MPC.The proposed method was simulated with three area interconnected power system and the efficiency of the proposed method was measured and exhibited by comparing with conventional Proportional and Integral(PI)controller and Linear Quadratic Regulation(LQR). 展开更多
关键词 Load frequency control model PREDICTIVE CONTROLLER orthonormal basis FUNCTION kautz FUNCTION phase plane analysis linear QUADRATIC REGULATOR proportional and integral CONTROLLER genetic algorithm.
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Diagenesis-porosity evolution and“sweet spot”distribution of low permeability reservoirs:A case study from Oligocene Zhuhai Formation in Wenchang A sag,Pear River Mouth Basin,northern South China Sea 被引量:1
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作者 YOU Li XU Shouli +3 位作者 LI Cai ZHANG Yingzhao ZHAO Zhanjie ZHU Peiyuan 《Petroleum Exploration and Development》 2018年第2期251-263,共13页
The characteristics of low permeability reservoirs and distribution of sweet spots in the Oligocene Zhuhai Formation of Wenchang A sag, Pearl River Basin were investigated by core observation and thin section analysis... The characteristics of low permeability reservoirs and distribution of sweet spots in the Oligocene Zhuhai Formation of Wenchang A sag, Pearl River Basin were investigated by core observation and thin section analysis. The study results show that there develop the fine, medium and coarse sandstone reservoirs of tidal flat–fan delta facies, which are of mostly low permeability and locally medium permeability. There are two kinds of pore evolution patterns: oil charging first and densification later, the reservoirs featuring this pattern are mainly in the third member of Zhuhai Formation between the south fault zone and the sixth fault zone, and the pattern of densification first and gas charging later is widespread across the study area. Strong compaction and local calcium cementation are the key factors causing low permeability of the reservoirs in the Zhuhai Formation. Thick and coarse grain sand sedimentary body is the precondition to form "sweet spot" reservoirs. Weak compaction and cementation, dissolution, early hydrocarbon filling and authigenic chlorite coating are the main factors controlling formation of "sweet spot" reservoir. It is predicted that there develop between the south fault and sixth fault zones the Class Ⅰ "sweet spot" in medium compaction zone, Class Ⅱ "sweet spot" in nearly strong compaction zone, Class Ⅲ "sweet spot" reservoir in the nearly strong to strong compaction zone with oil charging at early stage, and Class IV "sweet spot" reservoir in the strong compaction and authigenic chlorite coating protection zone in the sixth fault zone. 展开更多
关键词 low permeability reservoir pore evolution hydrocarbon charging 'sweet spot' distribution Zhuhai Formation OLIGOCENE Wenchang A SAG northern South China Sea
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