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Formalisms to Support the Definition of Processes

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Journal of Computer Science & Technology 2009年第2期24卷 198-211页

作者： leon J. Osterweil Department of Computer Science University of Massachusetts Amherst

This paper emphasizes the importance of defining processes rigorously, completely, clearly, and in detail in order to support the complex projects that are essential to the modern world. The paper argues that such process definitions provide needed structure and context for the development of effective software systems. The centrality of process is argued by enumerating seven key ways in which processes and their definitions are expected to provide important benefits to society. The paper provides an example of a process formalism that makes good progress towards the difficult goal of being simultaneously rigorous, detailed, broad, and clear. Early experience suggests that these four key characteristics of this formalism do indeed seem to help it to support meeting the seven key benefits sought from process definitions. Additional research is suggested in order to gain more insights into needs in the area of process definition formalisms.

关键词： processes process definition process language

A Random Nonstationary Pulse Train Model

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Journal of Beijing Institute of Technology 2021年第3期30卷 228-237页

作者： leon Cohen Department of Physics Hunter College of the City University of New York695 Park Ave.New YorkNY 10065USA

A simple and mathematically tractable model of a nonstationary process is *** process is the sum of waves where the parameters of the waves are *** expres-sions for the mean and autocorrelation function at each position as a function of time are *** the case of infinite time,the model evolves into a stationary *** time-frequency distri-bution at each position is also *** explicit example is given where the initial waves are *** case where there is dispersion in the propagation is also discussed.

关键词： nonstationary process mean and autocorrelation function time-frequency distribution Gaussian waves

Optical clearing of the mouse skull

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Light(Science & Applications) 2022年第10期11卷 2267-2268页

作者： chris Xu School of Applied and Engineering Physics Cornell UniversityIthacaNY 14853USA

High spatial resolution imaging of the mouse brain through the intact skull is challenging because of the skull-induced aberration and *** research group of Dan Zhu from Huazhong University of Science and Technology has developed a skull-clearing technique that provides a long-term(~weeks),stable,transparent window for high resolution optical imaging over a large field of view.

关键词： scattering. transparent Optical

Socioecological drivers facilitating biodiversity conservation in traditional farming landscapes

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Ecosystem Health and Sustainability 2015年第9期1卷 8-17页

作者： ine Dorresteijn Jacqueline Loos Jan Hanspach Joern Fischer Faculty of Sustainability Leuphana University LuneburgScharnhorststraße 121335 LuneburgGermany

Traditional farming landscapes have evolved as tightly coupled socioecological systems that support high ***,land-use change severely threatens the high biodiversity of these *** nature conservation in such landscapes requires a thorough understanding of the key drivers underpinning *** empirical research on mammals,birds,butterflies,and plants in a traditional cultural landscape in Romania,we revealed seven hypothesized drivers facilitating biodiversity *** proportions of three main land-use types support the landscape species pool,most likely through habitat connectivity and frequent spillover between land-use *** complementation and supplementation provide additional habitat for species outside their core *** of woody vegetation cover and gradients in land-cover heterogeneity provide mosaic landscapes with wide ranges of *** land-use practices underpin landscape heterogeneity,traditional land-use elements such as wood pastures,and human-carnivore ***-down predator control may limit herbivore ***,cultural ties between humans and nature have a central influence on people’s values and sustainable use of natural *** approaches should aim to maintain or restore these socioecological drivers by targeting the heterogeneous character of the forest-farmland mosaic at large scales through"broad and shallow"conservation *** large-scale measures should be complemented with"deep and narrow"conservation measures addressing specific land-use types,threats,or *** both cases,conservation measures should integrate the entire socioecological system,by recognizing and strengthening important links between people and the environment.

关键词： countryside biogeography coupled human and natural systems cultural landscapes human–environment systems landscape ecology resilience Romania Special Feature:Ecosystem Management in Transition in Central and Eastern Europe Transylvania

On the Fluid Dependence of Seismic Anisotropy:Beyond Biot-Gassmann

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Journal of Earth Science 2018年第6期29卷 1335-1339页

作者： leon Thomsen University of Houston Delta Geophysics

This work addresses the question of the fluid dependence of the non-dimensional parameters of seismic anisotropy. It extends the classic theory of the fluid-dependence of elasticity, and applies the approximation of weak seismic anisotropy. The analysis shows that reliance upon the classic theory leads to oversimplified conclusions. Extending the classic theory introduces new parameters（which must be experimentally determined） into the conclusions, making their application in the field context highly problematic.

关键词： Biot Gassmann incompressibility fluids fluid substitution pore compressibility

The emerging world of subcellular biological medicine:extracellular vesicles as novel biomarkers,targets,and therapeutics

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Neural Regeneration Research 2022年第5期17卷 1020-1022页

作者： leon G.Coleman The University of North Carolina at Chapel Hill School of MedicineDepartment of PharmacologyBowles Center for Alcohol StudiesChapel HillNCUSA

The COVID-19 pandemic,with all its tragedy,has also ushered in a new era of biological *** global crisis has brought along with it an opportunity that had not been foreseen by many-it brought the therapeutic use of su... 详细信息

关键词： hered brought opportunity

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Root architecture

Journal of Integrative Plant Biology 2016年第3期58卷 190-192页

作者： leon v.kochian robert w.holley center for agriculture and health usda-arscornell universityIthacaNY 14853USA

Numerous research publications over the past 20 years have made it quite clear that a better understanding of the molecular and genetic basis for variation in root system architecture（RSA）will greatly aid the develo... 详细信息

关键词： Root publications nutrient entitled limiting maize breeding pioneering roots drought

Laboratory and field evaluation of asphalt pavement surface friction resistance

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Frontiers of Structural and Civil Engineering 2018年第3期12卷 372-381页

作者： Zhong WU chris ABADIE Louisiana Transportation Research Center 4101 Gourrier Avenue Baton Rouge LA 70808 USA Louisiana Department of Transportation and Development 5080 Florida Blvd Baton Rouge LA 70806 USA

Pavement surface friction is a significant factor for driving safety and plays a critical role in reducing wet- pavement crashes. However, the current asphalt mixture design procedure does not directly consider friction as a requirement. The objective of this study was to develop a surface friction prediction model that can be used during a wearing course mixture design. To achieve the objective, an experimental study was conducted on the frictional characteristics of typical wearing course mixtures in Louisiana. Twelve wearing course mixtures including dense-graded and open-graded mixes with different combinations of aggregate sources were evaluated in laboratory using an accelerated polishing and testing procedure considering both micro- and macro texture properties. In addition, the surface frictional properties of asphalt mixtures were measured on twenty-two selected asphalt pavement sections using different in situ devices including Dynamic Friction Tester （DFT）, Circular Texture Meter （CTM）, and Lock-Wheel Skid Trailer （LWST）. The results have led to develop a procedure for predicting pavement end-of-life skid resistance based on the aggregate blend polish stone value, gradation parameters, and traffic, which is suited in checking whether the selected aggregates in a wearing course mix design would meet field friction requirements under a certain design traffic polishing.

关键词： friction skid resistance polishing PSV LWST micro-texture macro-texture

Effects of impeller speed and aeration rate on flotation performance of sulphide ore

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中国有色金属学会会刊：英文版 2006年第1期16卷 185-190页

作者：杨小生 ALDRICH chris Institute of Mineral Engineering Northeastern University Shenyang 110004 China Department of Process Engineering University of Stellenbosch Private Bag X1 Matieland Stellenbos ch 7602 South Africa

The effects of aeration rate and impeller speed on the concentrate sulfur grade and recovery for batch flotation of a complex sulphide ore were investigated. The relationships between the water recovery and solid entrainment were discussed. It is found that the solid entrainment is linearly related to the water recovery regardless of aeration rate and impeller speed, and the higher sulfur recovery at the aeration rate of 2 and 4 L/min for the impeller speed of 1 500 r/min is considered to be the contribution of true flotation. Finally, the sulfur recovery flux is correlated with the bubble surface area flux based on the froth image at the different aeration rates and impeller speeds.

关键词：水回收固体夹带浮选性能叶轮速度通风速率硫化矿