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Towards an L^p Potential Theory for Sub-Markovian Semigroups:Kernels and Capacities

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Acta Mathematica Sinica,English Series 2006年第4期22卷 1227-1250页

作者： Niels jacob RenéL.SCHILLING Department of Mathematics University of Wales SwanseaSingleton ParkSwansea SA 2 8 PP.United Kinadom FB 12-Mathematik Philipps-Universitat MarburgD-35032 MarburgGermany

We study in fairly general measure spaces （X,μ） the （non-linear） potential theory of L^p sub-Markovian semigroups which are given by kernels having a density with respect to the underlying measure. In terms of mapping properties of the operators we provide sufficient conditions for the existence （and regularity） of such densities. We give various （dual） representations for several associated capacities and, in the corresponding abstract Bessel potential spaces, we study the role of the truncation property. Examples are discussed in the case of R^n where abstract Bessel potential spaces can be identified with concrete function spaces.

关键词： nonlinear potential theory (r,p)-capacity Bessel potential space gamma.transform sub-Markovian semigroup

An efficient approach for anti-jamming in IRNSS receivers using improved PSO based parametric wavelet packet thresholding

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Satellite Navigation 2022年第3期3卷 51-70,I0003页

作者： jacob Silva Lorraine Kambham Madhu Ramarakula Department of ECE University College of EngineeringJNTUKKakinadaAndhra Pradesh533003India

The Indian Regional Navigation Satellite System provides accurate positioning service to the users within and around India,extending up to 1500 ***,when a receiver encounters a Continuous Wave Interference,its positioning accuracy degrades,or sometimes it even fails to *** Packet Transform(WPT)is the most widely used technique for anti-jamming in Global Navigation Satellite System *** the conventional method suffers from threshold drifting and employs inflexible thresholding ***,to address these issues,an efficient approach using Improved Particle Swarm Optimization based Parametric Wavelet Packet Thresholding(IPSO-PWPT)is ***,a new parameter adaptive thresholding function is ***,a new form of inertia weight is presented to enhance the performance of ***,IPSO is used to optimize the key parameters of ***,the implementation of the IPSO-PWPT anti-jamming algorithm is *** performance of the proposed technique is evaluated for various performance metrics in four jamming *** evaluation results manifest the proposed method’s efficacy compared to the conventional WPT in terms of anti-jamming ***,the results show the ability of the new thresholding function to process various signals ***,the findings reveal that the improved PSO outperforms the variants of PSO.

关键词： Continuous wave interference(CWI) IRNSS Particle swarm optimization(PSO) Wavelet packet transform(WPT)

The impact of seasonality on multi-scale feature extraction techniques

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International Journal of Digital Earth 2020年第1期13卷 9-21页

作者： Brian Moore jacob J.McKee Geographic Information Science and Technology Group Computational Sciences and Engineering DivisionOak Ridge National LaboratoryOak RidgeTNUSA

A key component in constructing a broad-scale,gridded population dataset is fine resolution geospatial data accurately depicting the extent of human *** datasets are often developed using a wide range of methods and classification techniques,including the use of spatial features,spectral features,or the coupling of both to identify the presence of man-made structures from high-resolution satellite *** using spatial and textural-based descriptors to generate highresolution settlement layers for two dissimilar regions at the peak of seasonal disparity,this study attempts to quantify the influence of seasonality on the accuracy of a supervised,multi-scale,feature extraction framework for automated delineation of human *** generated by numerous models are evaluated against a reference dataset allowing for assessment of seasonal and feature differences in the context of *** or regional mapping of human settlement requires the assemblage of high-resolution satellite images with variegated acquisition characteristics(season,sun elevation,off-nadir,etc.)to produce a cloud-free composite image from which features are *** of this study suggest an emphasis on imagery criteria,in particular acquisition date,could improve classification accuracy when mapping human settlement at scale.

关键词： Remote sensing highresolution imagery image processing human settlement accuracy

Enhancing accessibility to web mapping systems with technology-aligned adaptive profiles

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International Journal of Digital Earth 2014年第4期7卷 256-278页

作者： jacob Delfos Bert Veenendaal Tele Tan Department of Spatial Sciences Curtin UniversityPerthWAAustralia Department of Computing Curtin UniversityPerthWAAustralia

Web-based geographic information systems have advanced rapidly on the back of web-based technologies,increased bandwidths and access to Digital Earth imagery and ***,these advances are causing its capabilities to slowly overtake those of ***,the introduction of non-desktop devices such as smartphones,tablets and netbooks is starting to undo progress made towards standardisation of web-based *** varia-tions in screen sizes,computational power,bandwidth,and operating environ-ments are once again introducing the need to ensure software remains functional across different platforms,standards-compliant or *** two issues highlight the need for a mechanism to tune content and capability to end-users and their environment,to prevent information and complexity overload in a field already troubled by poor usability,while promoting cross-platform *** paper proposes the use of adaptivity to accommodate for users from different backgrounds accessing web mapping systems in different technical *** describes adaptive profiles aligned to the finite number of states a system can adopt,rather than the limitless range of user or environment characteristics that cannot be adapted *** profile consists of a combination of adaptive states comprising functionality,information detail,or technical demands to optimise for individual users or technical environments.

关键词： web mapping digital earth adaptivity usability compatibility user modelling

Two Types of Liquid Phase Separation Induced by Soft Centrifugation in Aqueous Ethyl Acetate Using Ethanol as Cosolvent

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Research 2023年第3期6卷 451-460页

作者： Helmut Cölfen Rose rosenberg Dirk Haffke Simon Stemplinger Thomas Zemb Dominik Horinek Physical Chemistry Department of ChemistryUniversity of KonstanzUniversitätsstr.10D-78457 KonstanzGermany Institute for Separation Chemistry ICSM U Montpellier/CEA/CNRS/ENSCM MarcouleFrance Institute of Physical and Theoretical Chemistry University of RegensburgD-93040 RegensburgGermany

Water/ethyl acetate/ethanol is widely used as a“green”extractant *** show that 2 different types of phase separation can be induced upon centrifugation in this ternary system using ethanol as a cosolvent of water and ethyl acetate:centrifuge-induced criticality and centrifuge-induced *** expected composition profiles of samples after centrifugation can be represented by bent lines in a ternary phase diagram when gravitational energy is added to the free energy of *** experimental equilibrium composition profiles behave qualitatively as expected and can be predicted using a phenomenological theory of *** concentration gradients are small except near the critical point,as expected for small ***,they are usable when accompanied by temperature *** findings open new possibilities of centrifugal separation,even if control is delicate during temperature *** schemes are accessible even at relatively low centrifugation speed for molecules that float and sediment with apparent molar masses several hundred times larger than the molecular mass.

关键词： separation ternary apparent

Awareness of non-alcoholic steatohepatitis and treatment guidelines:What are physicians telling us?

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World Journal of Hepatology 2021年第2期13卷 233-241页

作者： David Hermanus Wessels Zeil rosenberg Medical Office A.E.S.Chorley PR71NYLancashireUnited Kingdom Chief Medical Office Accelerated Enrollment SolutionsHorshamPA 19044United States

BACKGROUND There is an acute need to raise awareness of non-alcoholic fatty liver disease/nonalcoholic steatohepatitis(NAFLD/NASH)among primary care physicians,endocrinologists and diabetologists to improve patient identification and address the current difficulties in NASH clinical trial *** examined the extent of knowledge and practice regarding NASH diagnosis and management guidelines.A randomized online convenience survey of 12869 physicians drawn from a national physician database of primary care physicians(PCPs),and gastroenterology and endocrinology specialists were queried via online *** results,based on a cohort of 185 respondents,showed gaps in knowledge and practice between these three groups of practitioners,with primary care providers having the lowest adherence to published guidelines for diagnosis of *** clear knowledge and patient identification at the point of presentation-which is often in primary care or with specialties other than hepatology–many patients with NAFLD and NASH will remain undiagnosed and untreated,and clinical studies will continue to struggle with patient recruitment,hindering clinical development and optimal patient *** To determine knowledge base concerning NASH diagnosis amongst gastroenterologists,endocrinologists and primary care physicians to improve referrals into clinical *** A randomized online convenience survey of 12869 physicians drawn from a national physician database of PCPs,and gastroenterology and endocrinology specialists was conducted yielding a sample of 185 *** The survey revealed that many physicians are either unaware of testing options other than biopsy,or do not use them in *** 46%of endocrinologists and 42%of primary care physicians indicated they would refer a patient for specialist workup if they suspected ***(25%)and inconvenience to patients(18%)are given as reasons for not referring those with suspected NASH for *** stan

关键词： Non-alcoholic steatohepatitis Non-alcoholic fatty liver disease Enrollment Screening Diagnostics Guidelines

Evaluation of the 20 L dust explosibility testing chamber and comparison to a modified 38 L vessel for underground coal

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International Journal of Mining Science and Technology 2018年第6期28卷 885-890页

作者： Robert Eades Kyle Perry Catherine Johnson jacob Miller Department of Mining and Nuclear Engineering Missouri University of Science and Technology

The phenomenon of combustible dust explosions is present within many industries. Tests for explosibility of dust clouds per ASTM E1226 use a 20 L explosive chamber that places the combustible dust directly below the dispersion nozzle which generates a thorough mixture for testing purposes. However, in the underground coal mining industry, there are a number of geologic, mining, and regulatory factors that change the deposition scheme of combustible coal dust. This causes the atmosphere of a coal mine to have a variable rock dust-coal dust mixture at the time of ignition. To investigate the impact of this variable atmosphere, a series of lean explosibility tests were conducted on a sample of Pittsburgh Pulverized coal dust. These explosibility tests were conducted in a 38 L chamber with a 5 kJ Sobbe igniter. The 38 L chamber generates a variable air-dust mixture prior to ignition. The test results indicate that the 38 L chamber experiences reduced explosive pressures, and lower explosibility index values when compared to the 20 L chamber.

关键词： Dust explosion Coal mining Coal dust Explosibility testing

Single-port versus multi-port cholecystectomy for patients with acute cholecystitis: a retrospective comparative analysis

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Hepatobiliary & Pancreatic Diseases International 2011年第5期10卷 521-525页

作者： Dietmar jacob Roland Raakow Department of Surgery Center for Minimally Invasive Surgery Vivantes Hospital Spandau Neue Bergstrasse 6 13585 Berlin Germany Department of Surgery Vivantes Klinikum Am Urban Dieffenbachstrasse 1 10967 Berlin Germany

BACKGROUND: Trans-umbilical single-port laparoscopic cholecystectomy for chronic gallbladder disease is becoming increasingly accepted worldwide. But so far, no reports exist about the challenging single-port surgery for acute cholecystitis. The objective of this study was to describe our experience with single-port cholecystectomy in comparison to the conventional laparoscopic technique. METHODS: Between August 2008 and March 2010, 73 patients with symptomatic gallbladder disease and histopathological signs of acute cholecystitis underwent laparoscopic cholecystec- tomy at our institution. Thirty-six patients were operated on with the single-port technique (SP group) and the data were compared with a control group of 37 patients who were treated with the multi-port technique (MP group). RESULTS: The mean age in the SP group was 61.5 (range 21-81) years and in the MP group was 60 (range 21-94) (P=0.712). Gender, ASA status and BMI were not significantly different. The number of white blood cells was different before [SP: 9.2 (range 2.8-78.4); MP: 13.2 (range 4.4-28.6); P=0.001] and after the operation [SP: 7.8 (range 3.5-184.8); MP: 11.1 (range 5-20.8); P=0.002]. Mean operating time was 88 (range 34-174) minutes in the SP group vs 94 (range 39-209) minutes in the MP group (P=0.147). Four patients (5%) required conversion to an open procedure (SP: 1; MP: 3; P=0.320). During the follow- up period of 332 (range 29-570) days in the SP group and 428 (range 111-619) days in the MP group (P=0.044), eleven (15%) patients developed postoperative complications (P=0.745) and two patients in the SP group required reoperation (P=0.154). CONCLUSIONS: Trans-umbilical single-port cholecystectomy for beginning acute cholecystitis is feasible and the complicationrate is comparable with the standard multi-port operation. In spite of our good results, these operations are difficult to perform and should only be done in high-volume centers for laparoscopic surgery with experience in sin

关键词： laparoscopic surgery single-port cholecystectomy acute cholecystitis

Effect of post-thermal annealing on the structural and optical properties of ZnO thin films prepared from a polymer precursor

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Chinese Physics B 2012年第7期21卷 551-558页

作者： Jijoy.P.Mathew George Varghese jacob Mathew Thin Film Research Laboratory Department of PhysicsSt.Berchmans CollegeChanganasseryKerala 686101India Department of Physics Calicut UniversityThenjippalamKeralaIndia

ZnO thin films were synthesised by a new method which uses polyvinyl alcohol （PVA） as the polymer precursor. The films are annealed at different temperatures and for different annealing times. The structural parameters, like grain size, lattice constants, optical band gap, and Urbach energy, depend on the annealing temperature and time. All the films possess tensile strain, which relaxes as the annealing temperature and time increase. The photoluminescence （PL） spectra contain only ultraviolet （UV） peaks at low temperature, but as the annealing temperature and time increase, we observe peaks at the blue and green regions with a variation in the intensities of these peaks with annealing temperature and time.

关键词： stress, band gap, Urbach energy photoluminescence