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Spatio-Temporal Analysis of Landuse/Landcover Change of District Pishin Using Satellite Imagery and GIS

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Journal of Geographic Information System 2016年第3期8卷 361-368页

作者： Sanaullah khan Said Qasim Romana Ambre.n Zia-Ul-Haq Syed Department of Geography University of Balochistan Quetta Pakistan

Detecting change on the face of the globe using GIS (Geographic Information System) aided by remotely sensed imagery is now becoming an indispensable tool in managing the resources of our planet. The present study with the help of GIS and remote sensing (RS) is also a similar attempt in recording and quantifying change in land use and land cover in district Pishin both in spatial and temporal extents. Satellite imagery was acquired from the USGS official website from three LAnDSAT satellites. Theses satellites are LAnDSAT 5, LAnDSAT7 and LAnDSAT 8. The data were acquired for the years 1992, 2003 and 2013. Satellite imagery was processed in ArcMap 10.1 and maximum likelihood supervised image classification was applied in reaching the goal of detecting change. The result of the analysis revealed that built-up area was increased by 5.84%;vegetation was increased by 3.89%;water bodies were increased by 0.05% and bare surfaces were decreased by 9.78%. The decrease in the barren surfaces was attributed to the increase in vegetation and built-up area which replaced the barren land in the study area. This paper also shows the significance and potential of digital change detection methods in managing the resources of our environment and keeping an eye on the land use and land cover of our Earth.

关键词： Spatial-Temporal Land-Cover Change District Pishin GIS Satellite Imagery

Fractional single-phase-lagging heat conduction model for describing anomalous diffusion

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Propulsion and Power research 2016年第1期5卷 45-54页

作者： T.n.Mishra K.n.Rai DST-CIMS Faculty of SciencesBHUVaranasiUP 221005India Mathematical Sciences IIT BHUVaranasiUP 221005India

The fractional single-phase-lagging(FSPL)heat conduction model is obtained by combining scalar time fractional conservation equation to the single-phase-lagging(SPL)heat conduction *** on the FSPL heat conduction model,anomalous diffusion within a finite thin film is *** effect of different parameters on solution has been observed and studied the asymptotic behavior of the FSPL *** analytical solution is obtained using Laplace transform *** whole analysis is presented in dimensionless *** examples of particular interest have been studied and discussed in details.

关键词： Single-phase-lagging(SPL)heat conduction model Fractional single-phase-lagging(FSPL)heat conductionmodel Laplace transform Fractional conservation equation Asymptotic behavior Anomalous diffusion

Evaluation of sampling strategies to estimate crown biomass

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Forest Ecosystems 2015年第1期2卷 20-30页

作者： Krishna P Poudel Hailemariam Temesgen Andrew n Gray Department of Forest Engineering Resources and Management College of Forestry Oregon State University USDA Forest Service PNW Research Station3200 SW Jefferson WayCorvallis OR 97331 USA

Background：Depending on tree and site characteristics crown biomass accounts for a significant portion of the total aboveground biomass in the *** biomass estimation is useful for different purposes including evaluating the economic feasibility of crown utilization for energy production or forest products,fuel load assessments and fire management strategies,and wildfire ***,crown biomass is difficult to predict because of the variability within and among species and *** the allometric equations used for predicting crown biomass should be based on data collected with precise and unbiased sampling *** this study,we evaluate the performance different sampling strategies to estimate crown biomass and to evaluate the effect of sample size in estimating crown ***：Using data collected from 20 destructively sampled trees,we evaluated 11 different sampling strategies using six evaluation statistics：bias,relative bias,root mean square error（RMSE）,relative RMSE,amount of biomass sampled,and relative biomass *** also evaluated the performance of the selected sampling strategies when different numbers of branches（3,6,9,and 12）are selected from each *** specific log linear model with branch diameter and branch length as covariates was used to obtain individual branch ***：Compared to all other methods stratified sampling with probability proportional to size estimation technique produced better results when three or six branches per tree were ***,the systematic sampling with ratio estimation technique was the best when at least nine branches per tree were *** the stratified sampling strategy,selecting unequal number of branches per stratum produced approximately similar results to simple random sampling,but it further decreased RMSE when information on branch diameter is used in the design and estimation ***：Use of auxiliary information in design or estimation phase reduc

关键词： Aboveground biomass Crown Sampling strategies Pacific northwest

Comprehensive spectral analysis of Cyg X-1 using RXTE data

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research in Astronomy and Astrophysics 2012年第10期12卷 1427-1438页

作者： Rizwan Shahid Ranjeev Misra S.n.A.Jaaffrey Department of Physics M.L.Sukhadia UniversityUdaipur-313001India Inter University Centre for Astronomy and Astrophysics Pune-411007India

We analyze a large number （〉 500） of pointed Rossi X-Ray Timing Explorer （RXTE） observations of Cyg X- 1 and model the spectrum of each one. A subset of the observations for which there is a simultaneous reliable measure of the hardness ratio by the All Sky Monitor shows that the sample covers nearly all the spectral shapes of Cyg X-1. Each observation is fitted with a generic empirical model consisting of a disk black body spectrum, a Comptonized component whose input photon shape is the same as the disk emission, a Gaussian to represent the iron line and a reflection feature. The relative strength, width of the iron line and the reflection parameter are in general correlated with the high energy photon spectral index F. This is broadly consistent with a geometry where for the hard state （low F ~ 1.7） there is a hot in- ner Comptonizing region surrounded by a truncated cold disk. The inner edge of the disk moves inwards as the source becomes softer till finally in the soft state （high F 〉 2.2） the disk fills the inner region and active regions above the disk produce the Comptonized component. However, the reflection parameter shows non-monotonic behavior near the transition region （F ~ 2）, which suggests a more complex geometry or physical state of the reflector. In addition, the inner disk temperature, during the hard state, is on average higher than in the soft one, albeit with large scatter. These inconsistencies could be due to limitations in the data and the empirical model used to fit them. The flux of each spectral component is well correlated with F, which shows that unlike some other black hole systems, Cyg X- 1 does not show any hysteresis be- havior. In the soft state, the flux of the Comptonized component is always similar to the disk one, which confirms that the ultra-soft state （seen in other brighter black hole systems） is not exhibited by Cyg X-1. The rapid variation of the Compton amplifica- tion factor with F naturally explains the absence of spec

关键词： accretion accretion disks -- X-rays: binaries

Measurement of the spatial specific impulse distribution due to buried high explosive charge detonation

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Defence Technology（防务技术） 2017年第3期13卷 219-227页

作者： V. Denefeld n. Heider A. Holzwarth Fraunhofer Institute for High-Speed Dynamics Ernst-Mach-Institut EMI Ernst-Mach-Institut

Buried high explosive(HE) charges represent a high threat to military vehicles. The detonation of these charges can lead to significant momentum transfer onto vehicles and their occupants. A detailed understanding of the physical processes involved in the loading of vehicle structures is necessary for an optimization of effective countermeasures and protection systems. A quantitative description of the local momentum distribution on the vehicle underbody due to the detonation process is of special importance. In the following, a new test setup is presented that allows the experimental determination of the specific impulse distribution. It is based on a ring arrangement where the elements are.nested into each other and the velocity of each ring is correlated with the local specific impulse at its *** momentum transfer to a vehicle depends on a number of influencing factors such as: charge mass,embedding material(e.g. sand, gravel, clay), density, water content, saturation, depth of burial, ground clearance and vehicle shape. The presented technology is applied to quantify the influence of the embedding material(alluvial sand, quartz sand), the burial depth and the water content on the local specific impulse distribution. The obtained data can be used as initial condition for the numerical simulation of occupant safety assessment and as input for empirical modeling of momentum transfer on structures.

关键词：装药爆炸比冲军用车辆测量空间炸药车辆结构包埋材料

Can intraluminal devices prevent or reduce colorectal anastomotic leakage:A review

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World Journal of Gastroenterology 2011年第40期17卷 4461-4469页

作者： Annelien n Morks Klaas Havenga Rutger J Ploeg Division of Abdominal Surgery Department of Surgery University Medical Center Groningen 9700 RB Groningen The Netherlands

Colorectal anastomotic leakage is a serious complication of colorectal surgery, leading to high morbidity and mortality rates. In recent decades, many strategies aimed at lowering the incidence of anastomotic leakage have been examined. The focus of this review will be on mechanical aids protecting the colonic anastomosis against leakage. A literature search was performed using MEDLInE, EMBASE, and The Cochrane Collaborative library for all papers related to prevention of anastomotic leakage by placement of a device in the colon. Devices were categorised as decompression devices, intracolonic devices, and biodegradable devices. A decompression device functions by keeping the anal sphincter open, thereby lowering the intraluminal pressure and lowering the pressure on the anastomosis. Intracolonic devices do not prevent the formation of dehiscence. However, they prevent the faecal load from contacting the anastomotic site, thereby preventing leakage of faeces into the peritoneal cavity. Many attempts have been made to find a device that decreases the incidence of AL;however, to date, none of the devices have been widely accepted.

关键词： Anastomotic leakage Colorectal surgery Complication rectum Device

Feature Selection for Cluster Analysis in Spectroscopy

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Computers, Materials & Continua 2022年第5期71卷 2435-2458页

作者： Simon Crase Benjamin Hall Suresh n.Thennadil College of Engineering IT&EnvironmentCharles Darwin UniversityCasuarinaNT 0909Australia Defence Science and Technology Group Edinburgh5111Australia Energy and resources Institute Charles Darwin UniversityCasuarinaNT 0909Australia

Cluster analysis in spectroscopy presents some unique challenges due to the specific data characteristics in spectroscopy,namely,high dimensionality and small sample *** order to improve cluster analysis outcomes,feature selection can be used to remove redundant or irrelevant features and reduce the ***,for cluster analysis,this must be done in an unsupervised manner without the benefit of data *** paper presents a novel feature selection approach for cluster analysis,utilizing clusterability metrics to remove features that least contribute to a dataset’s tendency to *** versions are presented and evaluated:The Hopkins clusterability filter which utilizes the Hopkins test for spatial randomness and the Dip clusterability filter which utilizes the Dip test for *** new techniques,along with a range of existing filter and wrapper feature selection techniques were evaluated on eleven real-world spectroscopy datasets using internal and external clustering *** newly proposed Hopkins clusterability filter performed the best of the six filter techniques ***,it was observed that results varied greatly for different techniques depending on the specifics of the dataset and the number of features selected,with significant instability observed for most techniques at low numbers of *** was identified that the genetic algorithm wrapper technique avoided this instability,performed consistently across all datasets and resulted in better results on average than utilizing the all the features in the spectra.

关键词： Cluster analysis spectroscopy unsupervised learning feature selection wavenumber selection

Intra-population genetic variance for grain iron and zinc contents and agronomic traits in pearl millet

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The Crop Journal 2016年第1期4卷 48-54页

作者： Mahalingam Govindaraj Kedar n.Rai Ponnusamy Shanmugasundaram International Crops research Institute for the Semi-arid Tropics (ICRISAT) Centre for Plant Breeding and Genetics Tamil Nadu Agricultural University

Crop biofortification is a sustainable approach for fighting micronutrient malnutrition in the world. The estimation of variance components in genetically broad-based populations provides information about their genetic architecture, allowing the design of an appropriate biofortification breeding method for cross-pollinated crops such as pearl millet. The objective of this study was to estimate intra-population genetic variance using self(S1) and half-sib(HS) progenies in two populations, AIMP92901 and ICMR312. Field trials were evaluated in two contrasting seasons(2009 rainy and 2010 summer; otherwise called environments) in Alfisols at ICRISAT, Patancheru. Analyses of variance showed highly significant variation for S1 s and HS progenies, reflecting high within-population genetic variation for both micronutrients and other key traits. However, the HS showed narrow ranges and lower genetic variances than the S1 for all of the traits. The micronutrients were highly positively correlated in S1(r = 0.77 to 0.86; P nd HS(r = 0.74 to 0.77; P nies of both populations, implying concurrent genetic improvement for both micronutrients. The genetic variance component was different among populations for Fe and Zn contents across environments, with AIMP92901 showing a greater proportion of dominance and ICMR312 greater additive variance for these micronutrients. The estimates of variance(additive and dominance) were specific for each population, given their dependence on the additive and dominance effects of the segregating loci, which also differ among populations. The possible causes for such differences were discussed. The results showed that the expression of these micronutrients in pearl millet shows largely additive variance, so that breeding high-iron hybrids will require incorporation of these micronutrient traits into both parental lines.

关键词： Genetic variance Iron Micronutrient malnutrition Pearl millet Zinc

Hybridization of Cnn with LBP for Classification of Melanoma Images

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Computers, Materials & Continua 2022年第6期71卷 4915-4939页

作者： Saeed Iqbal Adnan n.Qureshi Ghulam Mustafa Faculty of Information Technology University of Central PunjabLahorePakistan Department of Computer Sciences Bahria University Lahore CampusPakistan

Skin cancer(melanoma)is one of the most aggressive of the cancers and the prevalence has significantly increased due to increased exposure to ultraviolet ***,timely detection and management of the lesion is a critical consideration in order to improve lifestyle and reduce *** this end,we have designed,implemented and analyzed a hybrid approach entailing convolutional neural networks(Cnn)and local binary patterns(LBP).The experiments have been performed on publicly accessible datasets ISIC 2017,2018 and 2019(HAM10000)with data augmentation for in-distribution *** a novel contribution,the Cnn architecture is enhanced with an intelligible layer,LBP,that extracts the pertinent visual *** of Basal Cell Carcinoma,Actinic Keratosis,Melanoma and Squamous Cell Carcinoma has been evaluated on 8035 and 3494 cases for training and testing,*** outcomes with cross-validation depict a plausible performance with an average accuracy of 97.29%,sensitivity of 95.63%and specificity of 97.90%.Hence,the proposed approach can be used in research and clinical settings to provide second opinions,closely approximating experts’intuition.

关键词： Skin cancer convolutional neural network feature extraction local binary pattern classification