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New opportunities and challenges in surveying underground cavities using photogrammetric methods

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International journal of mining Science and Technology 2021年第1期31卷 9-13页

作者： malte j.m.Gurgel Axel Preusse Institute for mine Surveying Mining Subsidence Engineering and Geophysics in MiningRWTH Aachen UniversityAachen 52062Germany

The exploitation of the underground is currently undergoing a major transformation *** mining,alternative ways of utilization are playing an increasingly important *** alternative utilizations include the storage of gases,the disposal of radioactive wastes,and the implementation of geothermal storage *** addition,more and more mining operations are being shut down,like the German hard coal mining industry in *** the integrity of closed mines must be ensured in the post-mining *** order to capture such large and complex structures efficiently and reliably,new surveying techniques are required.A promising approach is the use of photogrammetric methods to generate three-dimensional models of the *** is currently known mainly from aerial *** is conceivable to use such methods for underground *** recent years,significant progress has been made in the algorithm-based orientation of unstructured image *** powerful computer systems and the growing range of unmanned aerial vehicles could enable partially automated ***,a number of problems have to be solved for underground imaging *** exposure conditions complicate image ***,the models must be integrated into existing surveying systems with a sufficiently high degree of *** order to consider the numerous technical aspects,the development of an integrated capture and evaluation approach is *** could make an important contribution to the monitoring of critical cavities of different *** an approach would also fit into the current digitization trend in the mining industry and provide new opportunities for ground control in particular.

关键词： Photogrammetry Surveying Subsurface spatial planning

Conforming Hierarchical Basis Functions

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Communications in Computational Physics 2012年第9期12卷 1215-1256页

作者： m.j.Bluck Department of mechanical Engineering Imperial CollegeLondonSW72AZUK

A unified process for the construction of hierarchical conforming bases on a range of element types is proposed based on an ab initio preservation of the underlying *** process supports not only the most common simplicial element types,as are now well known,but is generalized to squares,hexahedra,prisms and importantly *** these latter cases have received(to varying degrees)attention in the literature,their foundation is less well developed than for the simplicial *** generalization discussed in this paper is effected by recourse to basic ideas from algebraic topology(differential forms,homology,cohomology,etc)and as such extends the fundamental theoretical framework established by the work of Hiptmair[16-18]and Arnold et al.[4]for *** process of forming hierarchical bases involves a recursive orthogonalization and it is shown that the resulting finite element mass,quasi-stiffness and composite matrices exhibit exponential or better growth in condition number.

关键词： Finite elements vector basis functions differential forms

Exact solution of Schrdinger equation with q-deformed quantum potentials using Nikiforov–Uvarov method

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Chinese Physics B 2013年第11期22卷 166-173页

作者： Falaye B.j. Oyewumi K.j. Abbas m. Theoretical Physics Section Department of Physics University of Ilorin Physics Department Kebbi State University of Science and Technology

In this paper, we present the exact solution of the one-dimensional Schrrdinger equation for the q-deformed quantum potentials via the Nikiforov-Uvarov method. The eigenvalues and eigenfunctions of these potentials are obtained via this method. The energy equations and the corresponding wave functions for some special cases of these potentials are briefly discussed. The PT-symmetry and Hermiticity for these potentials are also discussed.

关键词： Schrōdinger equation q-deformed quantum potential Woods-Saxon potential Nikiforov-Uvarovmethod

Why has canine rabies remained endemic in the Kilosa district of Tanzania? Lessons learnt and the way forward

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Infectious Diseases of Poverty 2015年第1期4卷 88-94页

作者： m.j.Kipanyula Department of Veterinary Anatomy Faculty of Veterinary MedicineSokoine University of AgricultureP.O.Box 3016Chuo KikuuMorogoroTanzania

Background:Domestic dogs are the main targets for rabies control as they are the principal reservoir for transmission of the rabies virus to humans and other domestic *** purpose of this study was to identify the factors that contribute to the rabies virus infecting the human population in a rural community of Eastern ***:Using a cross-sectional study design,field visits were conducted to gather information on villagers’knowledge on and practices associated with canine rabies control and dog vaccination ***:A total of 248 individuals were interviewed in the Kilosa district,*** two-thirds(61.3%)had a primary school *** majority(91.1%)of the respondents were aware that rabies is acquired through dog bites and 66.9%knew about the clinical signs of rabies in an *** few(17.7%),however,were aware of the clinical signs of rabies in *** 20.4%of the respondents knew how rabies is controlled in dogs and 71%were not aware of dog vaccination *** average number of dogs kept per household was 4±3.3;70.0%of the respondents had one to five dogs,28.3%had six to dog dogs,and 1.6%had 16–20 *** dogs were primarily used to guard livestock and property,and to *** 59.7%of the respondents indicated that rabies was a public health *** vaccination coverage was observed in the study area,with previous mass vaccination campaigns covering only 24.4%of the dog *** appeared to have limited value in the studied ***,there were no proper waste disposal facilities and oftentimes wild canids and felids visited the villages to scavenge on kitchen ***:Although communities in the Kilosa district had knowledge on rabies in dogs,they were not aware of the public health implication of the disease,which thus led a poor response during mass dog vaccination *** of a well-coordinated rabies control program,strategic public health awareness camp

关键词： Rabies Zoonotic disease Dog bite Vaccination Kilosa Tanzania

Increase in the Hydrophilicity and Lewis Acid-Base Properties of Solid Surfaces Achieved by Electric Gliding Discharge in Humid Air: Effects on Bacterial Adherence

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Plasma Science and Technology 2009年第2期11卷 187-193页

作者： j.O.KAmGANG m.NAITALI j.-m.HERRY m.-N.BELLON-FONTAINE j.-L.BRISSET R.BRIANDET Laboratory of Interfacial Electrochemistry and Analytical Chemistry University of Rouen INRA(National Institute for Agricultural Research) UMR 763 Bio-adhesion and Hygiene of Materials AgroParisTech UMR 763 Bio-adhesion and Hygiene of Materials AgroParisTech UMR763 Bio-adhesion and Hygiene of Materials

This study addressed the effects of treatment with gliding discharge plasma on the surface properties of solid materials, as well as the consequences concerning adherence of a model bacterium. As evaluated by contact angles with selected liquids, plasma treatment caused an increase in surface hydrophilicity and in the Lewis acid-base components of the surface energy of all materials tested. These modifications were more marked for low density polyethylene and stainless steel than for polytetrafiuoroethylene. After treatment, the hydrophilicity of the materials remained relatively stable for at least 20 days. moreover, analysis of the topography of the materials by atomic force microscopy revealed that the roughness of both polymers was reduced by glidarc plasma treatment. As a result of all these modifications, solid substrates were activated towards micro-organisms and the adherence of S. epidermidis, a negatively charged Lewis-base and mildly hydrophilic strain selected as the model, was increased in almost all the cases tested.

关键词： gliding arc plasma surface energy properties polymers stainless steel surface hydrophilicity atomic force microscopy

3D kinematicmandiblemodel to designmandibular advancement devices for the treatment of obstructive sleep apnea

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Bio-Design and manufacturing 2021年第1期4卷 22-32页

作者： m.García j.A.Cabrera A.Bataller S.Postigo j.j.Castillo Department of mechanical Engineering University of MálagaC/Doctor Ortiz Ramos s/nAmpliación Campus Teatinos29071 MálagaSpain

mandibular advancement devices(mADs)are one of the treatments used for Obstructive sleep apnea(OSA).mADs try to maintain the mandible in an advanced position to keep the upper airways open when *** achieve this goal,most current mADs limit the mouth opening to a few *** study of the kinematic behaviour of the patient’s jaw is essential in order to design devices that allow greater aperture *** this purpose,a 3D multibody model that reproduces jaw movement has been developed in this *** this end,the movement of the lower incisor has been determined by means of a vision system and reflective *** addition,the kinematics of the temporomandibular joint has been ***,the device is designed and printed using a cam-follower *** way,the cam profiles and the followers are optimally designed and positioned for each patient depending on the physiognomy of the jaw and the opening and advancing movement prescribed by the specialist.

关键词： mandibular advancement device 3D mandible kinematics Cam-follower mechanism 3D printed devices

The unusual life history of a southern Iberian Peninsula population of Torleya major （Ephemeroptera： Ephemerellidae）

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Insect Science 2011年第5期18卷 583-589页

作者： m. j. Lopez-Rodriguez j. m. Tierno de Figueroa j. Alba-Tercedor Departamento de Biologia Animal Facultad de Ciencias Universidad de Granada Granada Spain

The nymphal biology of a population of Torleya major （Klapalek） in southem Iberian Peninsula was studied. An atypical life cycle pattern is described, with eggs hatching in August producing a fast-developing cohort with adults emerging in autumn and a second slow-developing cohort with adults emerging in spring of the following year. Nymphal growth occurred primarily in summer-autumn （in the first cohort） and in spring （in the second）. The origin of such a life history is discussed. Nymphs were collector-gatherers, consuming mainly detritus. Although ontogenetic shifts on the use of trophic resources were detected, similar food was utilized during the months when both cohorts cohabited, eliminating the possibility that the rapid growth of the first cohort could be related to the utilization of different food resources.

关键词： collector-gatherer life cycle mayfly nymphal feeding southern Iberian Peninsula

Thermal analysis in swirl motion of maxwell nanofluid over a rotating circular cylinder

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Applied mathematics and mechanics(English Edition) 2020年第9期41卷 1417-1430页

作者： A.AHmED m.KHAN j.AHmED Department of mathematics Quaid-i-Azam UniversityIslamabad 44000Pakistan Department of Basic Sciences University of Engineering and TechnologyTaxila 47050Pakistan

In this paper,the mechanism of thermal energy transport in swirling flow of the maxwell nanofluid induced by a stretchable rotating cylinder is *** rotation of the cylinder is kept constant in order to avoid the induced axially secondary ***,the novel features of heat generation/absorption,thermal radiation,and joule heating are studied to control the rate of heat *** effects of Brownian and thermophoretic forces exerted by the maxwell nanofluid to the transport of thermal energy are investigated by utilizing an effective model for the nanofluid proposed by *** whole physical problem of fluid flow and thermal energy transport is modelled in the form of partial differential equations(PDEs)and transformed into nonlinear ordinary differential equations(ODEs)with the help of the suitable flow *** acquired results through the technique bvp4c are reported graphically with physical *** analysis reveals that there is higher transport of heat energy in the maxwell nanoliquid for a constant wall temperature(CWT)as compared with the prescribed surface temperature(PST).Both thermophoretic and Brownian forces enhance the thermal energy transport in the flowing maxwell ***,the temperature distribution increases with increasing values of the radiation parameter and the Eckert *** is also noted that an increase in Reynolds number reduces the penetration depth,and as a result the flow and transport of energy occur only near the surface of the cylinder.

关键词： maxwell nanofluid rotating cylinder heat source/sink joule heating convective condition numerical solution

Distributed DC-Bus Signaling Control of Photovoltaic Systems in Islanded DC microgrid

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CSEE journal of Power and Energy Systems 2022年第6期8卷 1741-1750页

作者： Noushin Poursafar m.j.Hossain Seyedfoad Taghizadeh macquarie University SydneyNew South WalesAustralia

The stability of an islanded DC microgrid(DCmG)is highly dependent on the presence and performance of the backup energy storage system(BESS),due to the lack of main grid *** condition makes the DCmG vulnerable to the critical situation of absence of the BESS,which could be caused by a fault or being fully charged or *** paper presents an enhanced distributed DC-bus signaling control strategy for converters of photovoltaic systems(PVs)to make the islanded DCmG less dependent on the *** a conventional control approach that utilizes PVs to operate in maximum power point tracking(mPPT)mode and the BESS solely regulating DC-bus voltage,the proposed control method maintains DC-bus voltage via intelligently managing output powers of the *** proposed control method continuously monitors DC-bus voltage and regulates the output powers of all the PVs via switching between mPPT mode and voltage regulating ***,if the DC-bus voltage level is less than a predefined maximum level,the PVs work in mPPT mode;otherwise,the PVs work in voltage regulating mode to maintain DC-bus voltage at an acceptable *** switching between mPPT and voltage regulating control operations results in protecting the DCmG from unavoidable shutdowns conventionally necessary during the absence of the BESS ***,the proposed control method reduces oscillations on the DC-bus voltage during existence of the *** performance and effectiveness of the proposed control strategy are validated through different case studies in mATLAB/Simulink.

关键词： DC microgrid voltage stability islanding mode distributed control distributed generator(DG)