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Journal of Mountain Science 2019年第11期16卷 2577-2590页

作者： Kazem NOSRATI adrian LCOLLINS Department of Physical Geography School of Earth SciencesShahid Beheshti University*** TehranIran Sustainable Agriculture Sciences Department Rothamsted ResearchNorth WykeOkehamptonEX202SBUK

Soil erosion and land use type have long been viewed as being particularly important drivers of soil *** objectives of this study,therefore,were to select a new soil quality index(SQI)which varies significantly with land use/soil erosion,and to evaluate the new SQI using expert *** total,18 soil physical,chemical,and biochemical properties(indicators)were measured on 56 soil samples collected from four land use/soil erosion categories(rangeland/surface erosion,rangeland/subsurface erosion,cultivated land/surface erosion and dry-farming land/surface erosion).Principal component and classification analysis(PCCA)identified five PCs that explained 77.7%of the variation in soil properties with the biochemical PC varying significantly with land use/soil *** discriminant analysis(GDA)selected urease and clay as the most sensitive properties distinguishing the land use/soil erosion *** GDA canonical scores for the new SQI were significantly correlated with expert opinion soil surface summed scores(for soil movement,surface litter,pedestalling,rills and flow pattern)derived using the *** of the Interior Bureau of Land Management(BLM)method.A forward stepwise general regression model revealed that the new SQI values were explained by soil movement,surface litter,and the summed values of the soil surface ***,this study confirmed that soil quality in the study area in Iran is controlled by land use and corresponding soil erosion.

关键词： Soil quality index Land use Erosion status Soil enzyme activities Multivariate statistical techniques

AI and freedom for evolution in energy science

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能源与人工智能(英文) 2020年第1期1卷 131-132页

作者： adrian Bejan Duke University DurhamNCUnited States

Artifacts such as AI,written language,science and technology are ob-jects(devices,processes,methods)that,when added to the homo sapi-ens,enhance the effect of human *** we are a“human and machine species”that is mon... 详细信息

关键词： such freedom AI

Advantages of a Biomimetic Stiffness Profile in Pitching Flexible Fin Propulsion

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Journal of Bionic Engineering 2010年第2期7卷 113-119页

作者： Paul Riggs adrian Bowyer Julian Vincent Biomimetics Group Mechanical Engineering DepartmentUniversity of Bath

The use of oscillating flexible fins in propulsion has been the subject of several studies in recent years, but attention israrely paid to the specific role of stiffness profile in thrust *** profile is defined as the variation in localchordwise bending stiffness (EI) of a fin, from leading to trailing *** this study, flexible fins with a standard NACA0012shape were tested alongside fins with a stiffness profile mimicking that of a Pumpkinseed Sunfish (Lepomis gibbosus).The finswere oscillated with a pitching sinusoidal motion over a range of frequencies and amplitudes, while torque, lateral force andstatic thrust were *** the range of oscillation parameters tested, it was shown that the fin with a biomimetic stiffness profile offered a significantimprovement in static thrust, compared to a fin of similar dimensions with a standard NACA0012 aerofoil *** fin also produced thrust more consistently over each oscillation cycle.A comparison of fin materials of different stiffness showed that the improvement was due to the stiffness profile itself, andwas not simply an effect of altering the overall stiffness of the *** of the same stiffness profile were observed to follow thesame thrust-power curve, independent of the stiffness of the moulding *** fins were shown to produce up to26% greater thrust per watt of input power, within the experimental range.

关键词： biomimetic propulsion stiffness pitching flexible fin

On sustaining the ecology and livestock industry of the Bayanbuluk Grasslands

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Journal of Arid Land 2010年第1期2卷 57-63页

作者： adrian R WILLIAMS Pendragon Dryland Management Services

A short visit to the Bayanbuluk Grassland in the Tianshan Mountains, Xinjiang, PRC, revealed a number of environmental and livestock production problems, including grassland degradation, loss of grassland biodiversity, soil erosion and flash flooding downstream, decreased pasture productivity, and poor livestock nutrition (especially in winter) leading to stock losses and flocks and herds of low productivity. This paper describes those problems and then suggests some solutions. Short duration, high intensity grazing could be one of the solutions to both improving grassland condition and improving livestock nutrition. Local production of fodder crops for feeding in winter and spring deserves testing, using adapted strains of Alfalfa (Medicago sativa) and trialling fodder root crop production. It is important to realise that the land management objectives of scientists, administrators, herders and farmers may be similar, and that there are opportunities for land improvement through working together.

关键词： Bayanbuluk Grasslands Tianshan Mountains reversing grassland degradation improving livestock productivity

First thrust measurements in ionic multi-propeller rotational engines

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Propulsion and Power Research 2023年第1期12卷 44-58页

作者： adrian Ieta Marius Chirita Electrical and Computer Engineering Department SUNY OswegoOswegoNY 13126-3599USA Applied Physics/Condensed Matter Department National Institute for Research and Development in Electrochemistry and Condensed MatterTimisoaraRO-300224Romania

Rotary ionic engines(RIEs)with multi-coaxial contra-rotating propellers(12.6 cm diameter)and their axial thrust are investigated in laboratory conditions,in air at atmospheric pressure,for the first *** goal is to evaluate more advantageous configurations that may be scaled up and further help with development of rotary ionic *** propellers are designed with regular pin-emitter electrodes placed coaxially inside a cylindrical collector *** high voltage is applied,propellers spin generating conventional axial thrust which is measured with an electronic scale in a“see-saw”*** to 40 mN thrust was obtained in single propeller RIE at 2600 rpm,0.34 mA,37.5 kV,and an optimal collector electrode diameter of 17 *** thrust can be obtained with two and three propellers at constant current per propeller but at a decreased *** the axial propeller-separation showed that propeller-interaction is minimal above 5 ***-to-power and thrust-tocurrent ratios were calculated and *** experimentally confirm here for the first time that within certain limits,the thrust-to-power variation can be assessed by the propeller kinetic energy-to-power ratio and also by the impedance of the gap(voltage-to-current ratio).A comparison of RIE arrays performance with one,two,and three coaxial propellers and the same total number of propellers per array(six)is also *** arrays with multi-coaxial propellers can provide larger thrust densities than single-propeller ***,arrays employing two coaxial propeller unit may be more weight effective.

关键词： Ionic wind EHD pump Electrohydrodynamics Corona discharge Thrust-to-power Propeller Ion propulsion Plasma thrusters Electroaerodynamic thrusters Ionocraft

Building occupancy and energy consumption:Case studies across building types

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能源与人工环境(英文) 2021年第2期2卷 167-174页

作者： Sicheng Zhan adrian Chong Department of Building School of Design and EnvironmentNational University of Singapore4 Architecture DriveSingapore 117566Singapore

Past research has shown that occupancy information can be used to reduce building energy consumption through occupant-based controls and by mitigating wasteful occupant *** this study,we investigate the dynamic relationship between WiFi connection counts(as a proxy to occupancy)and building electricity consumption across four building typologies(office,lab,health center,and library).Our findings based on one year of data show a strong positive linear correlation between electricity consumption and WiFi count across all four building when the building is in *** data exploration also indicates higher interactions between occupants with the plug and lighting loads in office and lab space types as compared to in a health center and a ***,using principal component analysis(PCA)for feature extraction followed by Density-based spatial clustering of applications with noise(DBSCAN),we show that distinct clusters could be generated,characterized by an increase in the between-cluster variance and smaller within-cluster ***,we apply linear regression to manifest how the clustering results can be used to better model the variables.

关键词： Occupancy WiFi Building energy Clustering Energy conservation

Creation and Evaluation of a Multi-sensory Virtual Assembly Environment

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International Journal of Automation and computing 2008年第2期5卷 163-173页

作者： adrian R L Travis Department of Engineering University of Cambridge

The multi-modal information presentation, integrated into the virtual environment （VE）, has potential for stimulating different senses, improving the user＇s impression of immersion, and increasing the amount of information that is accepted and processed by the user＇s perception system. The increase of the useful feedback information may reduce the user＇s cognitive load, thus enhancing the user＇s efficiency and performance while interacting with VEs. This paper presents our creation of a multi-sensory virtual assembly environment （VAE） and the evaluation of the effects of multi-sensory feedback on the usability. The VAE brings together complex technologies such as constraint-based assembly simulation, optical motion tracking technology, and real-time 3D sound generation technology around a virtual reality workbench and a common software platform. The usability evaluation is in terms of its three attributes： efficiency of use, user satisfaction, and reliability. These are addressed by using task completion times （TCTs）, questionnaires, and human performance error rates （HPERs）, respectively. Two assembly tasks have been used to perform the experiments, using sixteen participants. The outcomes showed that the multi-sensory feedback could improve the usability. They also indicated that the integrated feedback offered better usability than either feedback used in isolation. Most participants preferred the integrated feedback to either feedback （visual or auditory） or no feedback. The participants＇ comments demonstrated that nonrealistic or inappropriate feedback had negative effects on the usability, and easily made them feel frustrated. The possible reasons behind the outcomes are also analysed by using a unifying human computer interaction framework. The implications, concluded from the outcomes of this work, can serve as useful guidelines for improving VE system design and implementation.

关键词： Usability virtual environment (VE) assembly simulation multi-sensory feedback task performance

AutoBPS-BIM:A toolkit to transfer BIM to BEM for load calculation and chiller design optimization

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Building Simulation 2023年第7期16卷 1287-1298页

作者： Zhihua Chen Zhang Deng adrian Chong Yixing Chen College of Civil Engineering Hunan UniversityChangshaHunan 410082China Key Laboratory of Building Safety and Energy Efficiency(Hunan University) Ministry of EducationChina Department of Building National University of Singapore4 Architecture Drive117566Singapore

This study developed a rapid building modeling tool,AutoBPS-BIM,to transfer the building information model(BIM)to the building energy model(BEM)for load calculation and chiller design *** eight-storey office building in Beijing,33.2 m high,67.2 m long and 50.4 m wide,was selected as a case study ***,a module was developed to transfer BIM in IFC format into BEM in *** air volume systems were selected for the air system,while water-cooled chillers and boilers were used for the central *** EnergyPlus model calculated the heating and cooling loads for each space as well as the energy consumption of the central ***,a chiller optimization module was developed to select the optimal chiller design for minimizing energy consumption while maintaining thermal *** available chillers were included,with capacities ranging from 471 kW to 1329 *** results showed that the cooling loads of the spaces ranged from 33 to 100 W/m^(2) with a median of 45 W/m^(2),and the heating load ranged from 37 to 70 W/m^(2) with a median of 52 W/m^(2).The central plant’s total cooling load under variable air volume systems was 1400 *** with the static load calculation method,the dynamic method reduced 33%of the chiller design *** two chillers were used,different chiller combinations’annual cooling energy consumption ranged from 10.41 to 11.88,averaging 11.12 kWh/m^(2).The lowest energy consumption was 10.41 kWh/m^(2) when two chillers with 538 kW and 1076 kW each were *** the proper chiller number with different capacities was critical to achieving lower energy consumption,which achieved 12.6%cooling system energy consumption reduction for the case study *** study demonstrated that AutoBPS-BIM has a large potential in modeling BEM and optimizing chiller design.

关键词： BIM building energy model EnergyPlus chiller design optimization AutoBPS-BIM

From Decision to Commitment： The Molecular Memory of Flowering

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Molecular Plant 2009年第4期2卷 628-642页

作者： Jessika adrian Stefano Torti Franziska Turck Max Planck Institute for Plant Breeding Research Carl von Linne Weg 10 50829 Koln Germany

During the floral transition the shoot apical meristem changes its identity from a vegetative to an inflorescence state. This change in identity can be promoted by external signals, such as inductive photoperiod conditions or vernalization, and is accompanied by changes in expression of key developmental genes. The change in meristem identity is usually not reversible, even if the inductive signal occurs only transiently. This implies that at least some of the key genes must possess an intrinsic memory of the newly acquired expression state that ensures irreversibility of the process. In this review, we discuss different molecular scenarios that may underlie a molecular memory of gene expression.

关键词： Memory floral commitment floral transition chromatin Polycomb group transcription regulatory network motif.

On the evolution of terrestrial planets:Bi-stability,stochastic effects,and the non-uniqueness of tectonic states

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Geoscience Frontiers 2018年第1期9卷 91-102页

作者： Matthew B.Weller adrian Lenardic Institute for Geophysics University of Texas at AustinUSA Lunar and Planetary Institute HoustonTXUSA Department of Earth Science Rice UniversityHoustonTX 77005USA

The Earth is the only body in the solar system for which significant observational constraints are accessible to such a degree that they can be used to discriminate between competing models of Earth's tectonic *** is a natural tendency to use observations of the Earth to inform more general models of planetary ***,our understating of Earth's evolution is far from *** recent years,there has been growing geodynamic and geochemical evidence that suggests that plate tectonics may not have operated on the early Earth,with both the timing of its onset and the length of its activity far from ***,the potential of tectonic bi-stability(multiple stable,energetically allowed solutions)has been shown to be dynamically viable,both from analytical analysis and through numeric experiments in two and three *** indicates that multiple tectonic modes may operate on a single planetary body at different times within its temporal *** also allows for the potential that feedback mechanisms between the internal dynamics and surface processes(e.g.,surface temperature changes driven by long term climate evolution),acting at different thermal evolution times,can cause terrestrial worlds to alternate between multiple tectonic states over giga-year *** implication within this framework is that terrestrial planets have the potential to migrate through tectonic regimes at similar‘thermal evolution times'(e.g.,points were they have a similar bulk mantle temperature and energies),but at very different'temporal times'(time since planetary formation).It can be further shown that identical planets at similar stages of their evolution may exhibit different tectonic regimes due to random ***,we will discuss constraints on the tectonic evolution of the Earth and present a novel framework of planetary evolution that moves toward probabilistic arguments based on general physical principals,as opposed to particular rheol

关键词： Planetary interiors Mantle convection Lid-state Bi-stability Thermal evolution