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Two decades of variable retention in British Columbia: a review of its implementation and effectiveness for biodiversity conservation

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Ecological Processes 2019年第1期8卷 402-423页

作者： William J.Beese john deal B.Glen Dunsworth Stephen J.Mitchell Timothy J.Philpott Vancouver Island University 900 Fifth StreetNanaimoBC V9R 5S5Canada Western Forest Products 118–1334 Island Hwy.Campbell RiverBC V9W 8C9Canada Glen Dunsworth Ecological Consulting 7857 Shangri-La Rd.LantzvilleBC V0R 2H0Canada University of British Columbia 2424 Main MallVancouverBC V6T 1Z4Canada BC Min.of Forests Lands and Nat.Res.Oper400–640 Borland St.Williams LakeBC V2G 4T1Canada

Stand-level retention is an important component of sustainable forest management which aims to balance ecological,social and economic ***-term retention of mature forest structures at the time of harvesting(variable retention)is intended to produce future forest stands that more closely resemble conditions that develop after natural disturbances,thereby maintaining greater diversity of habitats for a variety of *** includes features such as live and dead trees representing multiple canopy layers,undisturbed understory vegetation and coarse woody *** the past two decades,variable retention has become common on forest lands in the temperate rainforests of coastal British Columbia(BC)and has been applied to a lesser extent in inland forest *** review of studies in BC and in similar forest types in our region indicates that both aggregated and dispersed retention can contribute to biodiversity conservation by providing short-term‘life-boating’habitat for some species and by enhancing the structural characteristics of future *** example,greater abundance of species present in the pre-harvest forest have been documented for vegetation,birds,carabid beetles,gastropods,ectomycorrhizal fungi and soil fauna in retention cutblocks compared to *** are,however,some negative consequences for timber production such as wind damage to retained trees and reduced growth rates of tree regeneration compared to *** authors suggest an adaptive management approach for balancing competing objectives when faced with *** includes monitoring the implementation and effectiveness of various strategies for achieving *** two decades of experience applying variable retention harvesting to industrial-scale management of forest lands in BC suggests that it is possible to balance production of wood with biodiversity conservation.

关键词： Alternative silvicultural systems Clearcutting Biological legacies Forest biodiversity Old-growth Variable retention British Columbia

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Net primary production in three bioenergy crop systems following land conversion

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Journal of Plant Ecology 2014年第5期7卷 451-460页

作者： Michael W.deal Jianye Xu Ranjeet john Terenzio Zenone Jiquan Chen Housen Chu Poonam Jasrotia Kevin Kahmark Jonathan Bossenbroek Christine Mayer Department of Environmental Sciences University of Toledo2801 West Bancroft StreetMail Stop 604ToledoOH 43606USA Great Lakes Bioenergy Research Center Michigan State University164 Food Safety and Toxicology BuildingEast LansingMI 48824USA W.K.Kellogg Biological Station Michigan State University3700 East Gull Lake DriveHickory CornersMI 49060USA

Aims Identifying the amount of production and the partitioning to above-and belowground biomass is generally the first step toward select-ing bioenergy *** are very few existing studies on the dynamics of production following land *** objectives of this study were to(i)determine the differences in aboveground net primary production(ANPP),belowground net primary produc-tion(BNPP),shoot-to-root ratio(S:R)and leaf area index in three bioenergy crop systems and(ii)evaluate the production of these three systems in two different land use *** This investigation included biometric analysis of NPP on three agri-cultural sites converted from conservation reserve program(CRP)management to bioenergy crop production(corn,switchgrass and prairie mix)and three sites converted from traditional agriculture production to bioenergy crop *** findings The site converted from conventional agriculture produced smaller ANPP in corn(19.03±1.90 standard error[SE]Mg ha^(−1) year^(−1))than the site converted from CRP to corn(24.54±1.43 SE Mg ha^(−1) year^(−1)).The two land conversions were similar in terms of ANPP for switchgrass(4.88±0.43 SE for CRP and 2.04±0.23 SE Mg ha^(−1) year^(−1) for agriculture)and ANPP for prairie mix(4.70±0.50 SE for CRP and 3.38±0.33 SE Mg ha^(−1) year^(−1) for agriculture).The BNPP at the end of the growing season in all the bioenergy crop systems was not significantly different(P=0.75,N=8).

关键词： bioenergy crops land use change net primary production aboveground net primary production belowground net primary production

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Mixing of powders and granular materials by mechanical means——A perspective

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Particuology 2012年第4期10卷 397-427页

作者： john Bridgwater Department of Chemical Engineering and Biotechnology University of CambridgePembroke StreetCambridge CB2 3RAUK Laboratory for Simulation and Modeling of Particulate Systems School of Materials Science and EngineeringThe University of New South WalesSydneyNSW 2052Australia

When engineers and scientists encounter the mixing of powders, they enter a subject where it is often difficult to find bearings. This perspective seeks to address this need by setting out the state of prac- tice. It then considers the growing momentum in the area following advances in computation and in measurement that became significant in the 1990s. The mixing of powders and granular materials is of central importance for the quality and performance of a wide range of products. However, process design and operation are very difficult, being largely based on judgement rather than science. There are not even tabulated data to tell how the quality of mixtures depends on mixer selection. Design depends on experience and insight, not science. There are no sound scale-up laws for a given equipment type, largely because particle size needs to be included in any dimensional analysis. Design is not possible by applying physical principles. There is no reliable equation to describe the flow of single component powders, let alone multi-component mixtures. In most cases, measurement has been difficult because the materials are optically opaque. Work in the research literature has been questionable because the results obtained for mixture sampling are affected by sample size. Recently, modern experimental techniques and modelling work have provided a good deal of infor- mation on the behaviour of many of the pieces of equipment, though these have been small in size and often confined to materials of a single size. However, the studies have enhanced knowledge of physical behaviour. For example, for a wide range of equipment when operating at lower velocities, mixing is determined by the number of revolutions of the mixer, not the time. Observations of flow structure have led to a few specific models that should scale with equipment size. Measurement techniques are slowly becoming more effective in giving internal flow patterns and in measuring powder composition. For cohe

关键词： PerspectivePowder mixingMixing of granular materialsCurrent designMixture qualityMixing mechanismsExperiments and computationsResearch trendsOpportunities for advanceSegregationCohesion

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Scheduling optimization of task allocation in integrated manufacturing system based on task decomposition

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Journal of Systems Engineering and Electronics 2016年第2期27卷 422-433页

作者： Aijun Liu Michele Pfund john Fowler Department of Management Engineering School of Economics & Management Xidian University Department of Supply Chain Management W.P. Carey School of Business Arizona State University

How to deal with the collaboration between task decomposition and task scheduling is the key problem of the integrated manufacturing system for complex products. With the development of manufacturing technology, we can probe a new way to solve this problem. Firstly, a new method for task granularity quantitative analysis is put forward, which can precisely evaluate the task granularity of complex product cooperation workflow in the integrated manufacturing system, on the above basis; this method is used to guide the coarse-grained task decomposition and recombine the subtasks with low cohesion coefficient. Then, a multi-objective optimieation model and an algorithm are set up for the scheduling optimization of task scheduling. Finally, the application feasibility of the model and algorithm is ultimately validated through an application case study.

关键词： integrated manufacturing system optimization task decomposition task scheduling

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Complementarity of CFD,experimentation and reactor models for solving challenging fluidization problems

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Particuology 2010年第6期8卷 498-500页

作者： john R. Grace Tingwen Li Department of Chemical and Biological Engineering University of British Columbia Vancouver V6T 1Z3 Canada National Energy Technology Laboratory 3610 Collins Ferry Rd Morgantown WV26507 USA

Experimentalists, numerical modellers and reactor modellers need to work together, not only just for validation of numerical codes, but also to shed fundamental light on each other＇s problems and underlying assumptions. Several examples are given, Experimental gas axial dispersion data provide a means of choosing the most appropriate boundary condition （no slip, partial slip or full slip） for particles at the wall of fluidized beds. CFD simulations help to identify how close ＂two-dimensional＂ experimental columns are to being truly two-dimensional and to representing three-dimensional columns. CFD also can be used to provide a more rational means of establishing assumptions needed in the modelling of two-phase fluidized bed reactors, for example how to deal with cases where there is a change in molar flow （and hence volumetric flow） as a result of chemical reactions.

关键词： Fluidization Mixing Computational Fluid dynamics Wall slip Reactor modelling Volume change

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Tracking and Sensor Coverage of Spatio-temporal Quantities Using a Swarm of Artificial Foraging Agents

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Journal of Bionic Engineering 2016年第4期13卷 679-689页

作者： john Oluwagbemiga Oyekan Dongbing Gu Huosheng Ha School of Aerospace Transport and Manufacturing Cranfield University College Road Cranfield MK43 OAL UK School of Computer Science and Electronic Engineering University of Essex Wivenhoe Park Colchester CO4 3SQ UK

Using a network of mobile sensors to track and map a dynamic spatio-temporal process in the environment is one of the current challenges in multi-agent systems. In this work, a distributed probabilistic multi-agent algorithm inspired by the bacte- rium foraging behavior is presented. The novelty of the algorithm lies in being capable of tracking and mapping a spa- tio-temporal quantity without the need of machine learning, estimation algorithms or future planning. This is unlike most current techniques that rely heavily on machine learning to estimate the distribution as well as the profile of spatio-temporal quantities. The experimental studies carried out in this work show that the algorithm works well by following the concentration gradient of a dynamic plume created under diffusive conditions. Furthermore, the algorithm is inherently capable of finding the source of a diffusive spatio-temporal quantity as well as performing environmental exploration. It is computationally tractable for simple agents, shown to adapt to its environment and can deal successfully with noise in sensor readings as well as in robot dynamics.

关键词： bioinspired algorithm artificial foraging swarm spatio-temporal mapping bacterium

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China's Economy in 2006/2007:Managing High Growth for Faster Structural Adjustment

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China & World Economy 2007年第2期15卷 1-15页

作者： john Wong East Asian Institute National University of Singapore

China ＇ s economy in 2006 continued to register high growth of l 0. 5 to 10. 7percent with low inflation （CPI at 1.3 percenO, dissipating fears of a hard landing. Since its accession to the WTO, China has become a significant global economic player, and is the favorite destination for many regional and global production networks. China is now a truly economic power （jingji daguo）. China ＇s economic leadership is also increasingly confident of its ability to manage China ＇s domestic economic growth and its growing relations with the outside world. Although China＇s growth is expected to slow down in 2007 to approximately 9.5 percent, the national mood now is one of ＂more balanced＂ growth rather than ＂＇fast growth ＂. Therefore, the building of a ＂harmonious society＂ is to be emphasized in China, while letting economic growth solve the burning social and environmental issues. In 2007, the government will also need to deal with various internal and external imbalances. The renminbi will be under even stronger pressure to revalue, given China ＂s record trade surplus of US$160bn and foreign reserves of US$1tn.

关键词： China's economy growth macroeconomic imbalance structural adjustment

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Optimizing oncolytic virus design:a“Swiss army knife”approach to create a systemically delivered therapeutic

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Signal Transduction and Targeted Therapy 2024年第5期9卷 1791-1792页

作者： Carolina S.Ilkow john Cameron Bell Ottawa Hospital Research Institute 501 Smyth RoadOttawaONK1H 8L6Canada

In a recent paper published in Nature Biotechnology,Chen et al.1 describe a multiplex oncolytic virus platform that coupled with adoptive T cell therapy could solve the problem of repeat,systemic delivery of virus based *** is widely accepted that multi-targeted therapeutic approaches attacking several facets of cancer biology are necessary to effectively deal with the tumor heterogeneity that exists within and between patients.

关键词： therapeutic al. targeted

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Time-series prediction of shellfish farm closure: A comparison of alternatives

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Information Processing in Agriculture 2014年第1期1卷 42-50页

作者： Ashfaqur Rahman Md Sumon Shahriar Claire D’Este Greg Smith john McCulloch Greg Timms Autonomous Systems Program CSIRO Computational InformaticsHobartTAS 7000Australia

Shellfish farms are closed for harvest when microbial pollutants are *** pollutants are typically present in rainfall runoff from various land uses in *** currently use a number of observable parameters(river flow,rainfall,salinity)as proxies to determine when to close *** have proposed using the short term historical rainfall data as a time-series prediction problem where we aim to predict the closure of shellfish farms based only on ***-series event prediction consists of two steps:(i)feature extraction,and(ii)prediction.A number of data mining challenges exist for these scenarios:(i)which feature extraction method best captures the rainfall pattern over successive days that leads to opening or closure of the farms?,(ii)The farm closure events occur infrequently and this leads to a class imbalance problem;the question is what is the best way to deal with this problem?In this paper we have analysed and compared different combinations of balancing methods(under-sampling and over-sampling),feature extraction methods(cluster profile,curve fitting,Fourier Transform,Piecewise Aggregate Approximation,and Wavelet Transform)and learning algorithms(neural network,support vector machine,k-nearest neighbour,decision tree,and Bayesian Network)to predict closure events accurately considering the above data mining *** have identified the best combination of techniques to accurately predict shellfish farm closure from rainfall,given the above data mining challenges.

关键词： Aquaculture Shellfish farm closure Data mining Time series data

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Perspectives on Nonalcoholic Fatty Liver Disease:An Overview of Present and Future Therapies

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Journal of Clinical and Translational Hepatology 2017年第1期5卷 67-75页

作者： john Vizuete Alfredo Camero Mazyar Malakouti Karthik Garapati Julio Gutierrez Department of Medicine Division of GastroenterologyUniversity of Texas Health Science Center San AntonioSan AntonioTXUSA The Texas Liver Institute San AntonioTXUSA

Nonalcoholic fatty liver disease(NAFLD)represents a major public health *** therapies for this condition are scarce,but multiple agents with novel mechanisms of action are in *** we review the pathophysiology and natural history of NALFD,diagnostic testing and data for currently available treatment *** then turn our attention to promising developmental drugs and their respective *** the prevalence of fatty liver disease increases,clinicians will have more tools at hand for management of this *** conclude the horizon is bright for patients and doctors who deal with NAFLD.

关键词： Nonalcoholic fatty liver disease Fatty liver Steatohepatitis NAFLD NAFL NASH Developmental drugs Hepatic steatosis

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