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Using classification assignment rules to assess land-use change impacts on forest biodiversity at local-to-national scales

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Forest Ecosystems 2018年第2期5卷 162-176页

作者： Kathrin Affeld Susan K. Wiser ian j. Payton Miquel DeCaceres Manaaki Whenua - Landcare Research PO Box 69040 Lincoln 7640 New Zealand Lincoln University PO Box 85084 Lincoln 7647 New Zealand Forest Science Centre of Catalonia Ctra. Sant Llorenc km.2 E-25280 Solsona Spain

Background： Ecosystem representation is one key component in assessing the biodiversity impacts of land-use changes that will irrevocably alter natural ecosystems. We show how detailed vegetation plot data can be used to assess the potential impact of inundation by a proposed hydroelectricity dam in the Mokihinui gorge, New Zealand, on representation of natural forests. Specifically we ask： 1） How well are the types of forest represented Locally, regionally, and nationally; and 2） How does the number of distinct communities （i.e. beta diversity） in the target catchment compare with other catchments nationally？ Methods： For local and regional comparisons plant species composition was recorded on 45 objectively located 400 m2 vegetation plots established in each of three gorges, with one being the proposed inundation area of the Mokihinui lower gorge. The fuzzy classification framework of noise clustering was used to assign these plots to a specific alliance and association of a pre-existing national-scale classification. NationaLly, we examined the relationship between the number of alliances and associations in a catchment and either catchment size or the number of plots per catchment by fitting Generalised Additive Models. Results： The four alliances and five associations that were observed in the Mokihinui lower gorge arepresent in the region but limited locally. One association was narrowly distributed nationally, but is the mostfrequent association in the Mokihinui lower gorge; inundation may have consequences of national importance to its long-term persistence. That the Mokihinui lower gorge area had nearly twice as many plots that could not be assigned to pre- existing alliances and associations than either the Mokihinui upper or the Karamea lower gorges and proportionally more than the national dataset emphasises the compositional distinctiveness of this gorge. These outlier plots in the Mokihinui lower gorge may be unsorted assemblages of species or reflect

关键词： Beta-diversity Biodiversity conservation Environmental impacts Ecosystem representation Hydroelectricity dams Land-use change National vegetation classification Noise clustering New Zealand NVS databank Plant community composition

Interstitial strengthening in *** and alloys

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Advanced Powder Materials

Advanced Powder Materials 2022年第4期1卷 1-7页

作者： ian Baker Thayer SchoolofEngineering DartmouthCollegeHanoverNH03755USA

In this short review,we highlight instances where interstitials have been shown to substantially increase the yield strength and work-hardening rate(WHR)of ***,particularly high entropy alloys,medium entropy alloys,TWIP steels and stainless ***,the common practice of describing interstitial strengthening in *** using models that are used to explain substitutional strengthening appears to be neither appropriate nor *** we suggest,based on the literature,that the yield strength increase due to interstitials in *** is more appropriately described by a linear dependence on the concentration:due to a paucity of experimental studies,the dependence of the yield strength and WHR on misfit parameters is currently ***,the source of the strengthening remains unclear.A feature that has been observed in several *** is that interstitial additions lead to a change from wavy to planar slip although the origin of this change,which may be related to changes in stacking fault energy as well as other factors,remains *** paper concludes by outlining areas of future research,including the need to develop a new model for interstitial strengthening in ***.

关键词： Interstitials f.c.c.alloys High entropy alloys Yield strength Work-hardening rate

A fast and accurate model for the creation of explosion fragments with improved fragment shape and dimensions

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Defence Technology（防务技术） 2022年第2期18卷 159-169页

作者： David Felix ian Colwill Paul Harris School of Computing Engineering&MathematicsUniversity of BrightonBrightonUK Engineering and Design(Alumni) University of SussexBrightonUK

Explosion models based on Finite Element Analysis(FEA)can be used to simulate how a warhead *** their execution times are *** protection systems need to make very fast predictions,before a fast attacking weapon hits the *** execution times are also needed in real time simulations where the impact of many different computer models is being ***,FEA explosion models are not appropriate for these real-time *** research presented in this paper delivers a fast simulation model based on Mott’s equation that calculates the number and weight of fragments created by an *** addition,the size and shape of fragments,unavailable in Mott’s equation,are calculated using photographic evidence and a distribution of a fragment’s length to its *** model also identifies the origin of fragments on the warhead’s *** results are verified against experimental data and a fast execution time is achieved using uncomplicated simulation *** developed model then can be made available for real-time simulation and fast computation.

关键词： Distribution of fragments Fragment shape Real-time simulation Cylindrical explosion

Lag times in toe-to-heel air injection(THAI)operations explain underlying heavy oil production mechanisms

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Petroleum Science 2022年第3期19卷 1165-1173页

作者： Wei Wei ian D.Gates Department of Chemical and Petroleum Engineering University of CalgaryCalgaryAlbertaCanada

From a time value of revenue point of view,it is preferred that the time between reservoir stimulation and oil production response is *** oil combustion processes have a lag time between air injection and liquid production,but the common practice in production data analysis uses simultaneous injection and production data when seeking a relationship between *** this research,the time scales of production for the Kerrobert toe-to-heel air injection(THAI)heavy oil project in Saskatchewan,Canada,is analyzed by using cross correlation analysis,*** delay analysis between air injection and oil *** results reveal two time scales with respect to production response with two distinctive recovery mechanisms:(1)a short time scale response(nearly instantaneous)where oil production peaks right after air injection(directly after opening production well)reflecting cold heavy oil production mechanisms,and(2)a longer time scale(of order of 100-300 days)response where peak production occurs associated with the collective phenomena of air injection,heat generating reactions,heat transfer,and finally,heated mobilized heavy oil drainage to the production *** understanding of the two time scales and associated production mechanisms provides a basis for improving the performance of THAI.

关键词： Heavy oil In situ combustion Toe-to-heel air injection(THAI) Production analysis Lag time

The ballistic performance of the bombard Mons Meg

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Defence Technology（防务技术） 2016年第2期12卷 59-68页

作者： ian LEWTAS Rachael MCALISTER Adam WALLIS Clive WOODLEY ian CULLIS QinetiQ Fort Halstead

The bombard Mons Meg, located in Edinburgh Castle, with a diameter of 19 inches(48 cm), was one of the largest calibre cannons ever *** in 1449 and presented to King james II of Scotland in 1454, Mons Meg was used in both military and ceremonial roles in Scotland until its barrel burst in 1680. This paper examines the history, internal, external and terminal ballistics of the cannon and its shot. The likely muzzle velocity was estimated by varying the propellant type and the cannon profile was investigated to identify weak spots in the design that may have led to its failure. Using the muzzle velocity calculated from the internal ballistics, simulations were performed with granite and sandstone shot for varying launch angle and ground temperature. The likely trajectory and range of the cannonballs are described. The internal and external ballistics informed the initial conditions of the terminal ballistic impact scenarios. The performance of the cannonball against both period and modern targets, in the form of a pseudo-castle wall and a monolithic concrete target, respectively, were simulated and are presented and discussed.

关键词：弹道性能 Meg 内弹道计算 19英寸速度估计地面温度弹道冲击苏格兰

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桉树人工育种方法学

桉树科技 1995年第2期12卷 62-74页

作者： j.turner M.W.Moncur R.Hand 罗林文

引言改良商业林的种植材料是一个长期不断的过程。种子最初是从自然林分和人工林的实生苗中采取;后来是采用林木选优,它是根据树木的特征,如材积、早期生长情况或抗病性来选择。可通过选出最好的基因进行组合,以进一行提高控制杂交群体... 详细信息

引言改良商业林的种植材料是一个长期不断的过程。种子最初是从自然林分和人工林的实生苗中采取;后来是采用林木选优,它是根据树木的特征,如材积、早期生长情况或抗病性来选择。可通过选出最好的基因进行组合,以进一行提高控制杂交群体增益。

关键词：桉树人工育种异花授粉花药培养

ZIKA-How fast does this virus mutate?

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Zoological Research 2016年第2期37卷 110-115页

作者： ian S.LOGAN Parkside Drive Exmouth Devon UK EX8 4LB. ianlogan22@***.

The World Health Organization has declared the present Zika virus epidemic to be a ＇Public Health Emergency of International Concern＇. The virus appears to have spread from Thailand to French Polynesia in 2013, and has since infected over a million people in the countries of South and Central America. In most cases the infection is mild and transient, but the virus does appear to be strongly neurotropic and the presumptive cause of both birth defects in fetuses and Guillain-Barr6 syndrome in some adults. In this paper, the techniques and utilities developed in the study of mitochondrial DNA were applied to the Zika virus. As a result, it is possible to show in a simple manner how a phylogenetic tree may be constructed and how the mutation rate of the virus can be measured. The study showed the mutation rate to vary between 12 and 25 bases a year, in a viral genome of 10 272 bases. This rapid mutation rate will enable the geographic spread of the epidemic to be monitored easily and may also prove useful in assisting the identification of preventative measures that are working, and those that are not.

关键词： Zika Virus Polyprotein Mutation rate Phylogenetic tree

N-Nitrosamine formation from chloramination of two common ionic liquids

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journal of Environmental Sciences 2020年第1期32卷 341-348页

作者： ian j.Vander Meulen Ping jiang Di Wu Steve E.Hrudey Xing-Fang Li Division of Analytical and Environmental Toxicology Department of Laboratory Medicine and PathologyFaculty of Medicine and DentistryUniversity of Alberta

Ionic liquids(ILs)are a class of solvents increasingly used as"green chemicals."Widespread applications of ILs have led to concerns about their accidental entry to the *** have been assessed for some environmental impacts;however,little has been done to characterize their potential impacts on drinking water if ILs accidentally enter surface *** cations are often aromatic or alkyl quaternary amines that resemble structures of previously confirmed N-nitrosamine(NA)***,this study has evaluated two common ILs,1-ethyl-3-methylimidazolium bromide(EMIm Br)and 1-ethyl-1-methylpyrrolidinium bromide(EMPyr Br),for their NA formation *** IL species was reacted with pre-formed monochloramine under various laboratory *** reaction mixtures were extracted using liquid–liquid extraction and analyzed for NAs using high performance liquid chromatography tandem mass *** low concentration of IL(250μmol/L),the yields of NAs(NMEA or NPyr)increased with increasing doses of monochloramine from both IL *** total NA yield was as high as 2.5±0.3 ng/mg from EMIm Br,and as high as 8.6±0.8 ng/mg from EMPyr *** high concentration of IL(5 mmol/L),the NA yield reached a maximum at 2.5 mmol/L NH2Cl,and then decreased with subsequent increases in the reactant concentrations,demonstrating ILs’solvent *** study re-emphasizes the importance of preventing discharge of ILs to water bodies to prevent secondary impacts on drinking water.

关键词： Ionic liquids N-nitrosamine Liquid–liquid extraction HPLC–MS/MS DBPs

Real-time calculation of fragment velocity for cylindrical warheads

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Defence Technology（防务技术） 2019年第3期15卷 264-271页

作者： David Felix ian Colwill Elias Stipidis Institution of Engineering and Technology Stevenage England Member of British Computer Society London Institute of Electrical and Electronics Engineers London

To simulate explosion fragments, it is necessary to predict many variables such as fragment velocity, size distribution and projection angle. For active protection systems these predictions need to be made very quickly, before the weapon hits the target. Fast predictions also need to be made in real time simulations when the impact of many different computer models need to be assessed. The research presented in this paper focuses on creating a fast and accurate estimate of one of these variables - the initial fragment velocity. The Gurney equation was the first equation to calculate initial fragment velocity. This equation, sometimes with modifications, is still used today where finite element analysis or complex mathematical approaches are considered too computationally expensive. This paper enhances and improves Breech’s two-dimensional Gurney equation using available empirical data and the principals of conservation of momentum and energy. The results are computationally quick, providing improved accuracy for estimating initial fragment velocity. This will allow the developed model to be available for real-time simulation and fast computation, with improved accuracy when compared to existing approaches.

关键词： Initial fragment velocity Real-time simulation Cylindrical explosion