Estimating life-form cover fractions in California sage scrub communities using multispectral remote sensing

The California sage scrub (CSS) community type in California's Mediterranean-type ecosystems is known for its high biodiversity and is home to a large number of rare, threatened, and endangered species. Because of extensive urban development in the past fifty years, this ecologically significant community type is highly degraded and fragmented. To conserve endangered CSS communities, monitoring internal conditions of communities is as crucial as monitoring distributions of the community type in the region. Vegetation type mapping and field sampling of individual plants provide ecologically meaningful information about CSS communities such as spatial distribution and species compositions, respectively. However, both approaches only provide spatially comprehensive information but no information about internal conditions or vice versa. Therefore, there is a need for monitoring variables which fill the information gap between vegetation type maps and field-based data. A number of field-based studies indicate that life-form fractional cover is an effective indicator of CSS community health and habitat quality for CSS-obligated species. This study investigates the effectiveness of remote sensing approaches for estimating fractional cover of true shrub, subshrub, herb, and bare ground in CSS communities of southern California. Combinations of four types of multispectral imagery ranging from 0.15 m resolution scanned color infrared aerial photography to 10 m resolution SPOT 5 multispectral imagery and three image processing models - per-pixel, object-based, and spectral mixture models - were tested.An object-based image analysis (OBIA) routine consistently yielded higher accuracy than other image processing methods for estimating all cover types. Life-form cover was reliably predicted, with error magnitudes as low as 2%. Subshrub and herb cover types required finer spatial resolution imagery for more accurate predictions than true shrub and bare ground types. Positioning of sampling grids had a substantial impact on the reliability of accuracy assessment, particularly for cover estimates predicted using multiple endmember spectral mixture analysis (MESMA) applied to SPOT imagery. Of the approaches tested in this study, OBIA using pansharpened QuickBird imagery is one of the most promising approaches because of its high accuracy and processing efficiency and should be tested for more heterogeneous CSS landscapes. MESMA applied to SPOT imagery should also be examined for effectiveness in estimating factional cover over more extensive habitat areas because of its low data cost and potential for conducting retrospective studies of vegetation community conditions.     

自适应UKF在北斗伪距定位中的研究

针对北斗伪距定中噪声统计特性未知或者不准确带来的定位精度不高问题,为减小噪声统计特性的不准确在滤波过程中对状态估计带来的影响,采用了无迹卡尔曼滤波(UKF)和噪声统计值估计器相结合的滤波方法,该方法在UKF中引入改进的噪声估计Sage-Husa算法,对系统噪声和观测噪声进行实时估计,抵抗不准确噪声在定位解算时带来的误差;最后在进行状态更新时引入一个收敛因子对每一次滤波状态进行更新,保证算法的收敛性。实验结果表明,该方法与传统的无迹卡尔曼滤波相比,在提升算法收敛速度的同时,将伪距定位的精度提高了40%左右,可用于带有时变噪声和未知噪声的定位系统中。     

基于改进Sage滤波器的车辆行程时间预测模型

在现代ITS环境中,公交车辆行程时间预测是实现公共交通智能化调度子系统、电子站牌显示子系统及公交信息服务子系统的必要条件。针对Sage滤波器自身的优缺点,提出了一种基于车辆行程时间历史数据流信息的Sage滤波器,并在此基础建立了BRT（Bus Rapid Transit）车辆行程时间预测模型。最后针对2007年6月7日北京市南中轴路大容量快速公交（BRT）线的实际数据进行了对比实验,结果表明,改进的Sage滤波器有效降低了原算法的误差。     

Quantification of 1,8‐cineole and of its metabolites in humans using stable isotope dilution assays

The metabolism of 1,8‐cineole after ingestion of sage tea was studied. After application of the tea, the metabolites 2‐hydroxy‐1,8‐cineole, 3‐hydroxy‐1,8‐cineole, 9‐hydroxy‐1,8‐cineole and, for the first time in humans, 7‐hydroxy‐1,8‐cineole were identified in plasma and urine of one volunteer. For quantitation of these metabolites and the parent compound, stable isotope dilution assays were developed after synthesis of [²H₃]‐1,8‐cineole, [9/10‐²H₃]‐2‐hydroxy‐1,8‐cineole and [¹³C,²H₂]‐9‐hydroxy‐1,8‐cineole as internal standards. Using these standards, we quantified 1,8‐cineole by solid phase microextraction GC‐MS and the hydroxyl‐1,8‐cineoles by LC‐MS/MS after deconjugation in blood and urine of the volunteer. After consumption of 1.02 mg 1,8‐cineole (19 μg/kg bw), the hydroxycineoles along with their parent compound were detectable in the blood plasma of the volunteer under study after liberation from their glucuronides with 2‐hydroxycineole being the predominant metabolite at a maximum plasma concentration of 86 nmol/L followed by the 9‐hydroxy isomer at a maximum plasma concentration of 33 nmol/L. The parent compound 1,8‐cineole showed a low maximum plasma concentration of 19 nmol/L. In urine, 2‐hydroxycineole also showed highest contents followed by its 9‐isomer. Summing up the urinary excretion over 10 h, 2‐hydroxycineole, the 9‐isomer, the 3‐isomer and the 7‐isomer accounted for 20.9, 17.2, 10.6 and 3.8% of the cineole dose, respectively.     

Flavonoid pattern of sage (Salvia officinalis L.) unifloral honey

The aim of the present paper was to determine the flavonoids in monofloral sage (Salvia officinalis L.) honey which is characteristic and specific for the area of Croatian coast and islands. For that purpose 38 sage honey samples from two production seasons were analysed. After specific pollen content determination, and analyses of selected physicochemical parameters which confirmed that samples are in compliance with national and international regulations and can be regarded as unifloral sage honeys, flavonoid fraction was isolated and analysed using RP-HPLC/DAD method. The HPLC analysis showed that all examined sage honey samples contain quercetin (3,3′,4′,5,7-pentahydroxyflavone), luteolin (3′,4′,5,7-tetrahydroxyflavone), kaempferol (3,4′,5,7-tetrahydroxyflavone), apigenin (4′,5,7-trihydroxyflavone), chrysin (5,7-dihydroxyflavone) and galangin (3,5,7-trihydroxyflavone), as well as p-coumaric (trans-4-hydroxycinnamic acid) and caffeic acid (3,4-dihydroxycinnamic acid). Total amount of identified flavonoids varied from 109.4 μg/100 g of honey to 589.9 μg/100 g of honey, with the average of 288.5 μg/100 g of honey. All analysed honey samples showed common and specific flavonoid profile which could be the basis for differentiating sage from other monofloral honeys.     

Determination of carnosic acid and rosmarinic acid in sage by capillary electrophoresis

A simple and rapid capillary electrophoresis method was developed for the identification and quantitative determination of two antioxidative compounds – carnosic acid and rosmarinic acid – in the extracts of commercial Sage (Salvia officinalis) tea-bags. Capillary zone electrophoretic separation of carnosic and rosmarinic acids was performed using 40 mmol/l borate, at pH 9.6 as the running buffer. Weighed sage samples were extracted from tea-bags by sonification and the extracts were directly injected without any purification and pre-separation process. Coumarin was used as internal standard for quantitation and the limits of detection for carnosic acid and rosmarinic acid were obtained as 2.79 and 3.18 μg/ml, respectively using UV detection at 210 nm.     

Instrumental geometry

For two decades, the individual members of the SmartGeometry Group have pioneered innovative computer-aided design (cad) techniques and technologies. Now that they are situated in key positions in internationally renowned companies, the group is involved in developing a new generation of parametric design software. Here, Robert Aish (Director of Research at Bentley Systems), Lars Hesselgren (Director of Research and Development, kpf London), J Parrish (Director of ArupSport) and Hugh Whitehead (Project Director of the Specialist Modelling Group, Foster and Partners, London) discuss with Achim Menges the group's instrumental approach to geometry and their unique collaboration spanning the world of practice and software development. Copyright © 2006 John Wiley & Sons, Ltd.     

Driving an Ecological Agenda with Project-Led Research

Here Hugh Whitehead, Irene Gallou, Harsh Thapar, Giovanni Betti and Salmaan Craig of the Specialist Modelling Group (SMG) at Foster + Partners directly address the underlying premise behind the issue. They argue the case for the architect as generalist or ‘centralised controller’, coordinating an often specialised and diverse collaborative design team. As an in-house consultancy within Foster + Partners, SMS provides expertise in complex geometry, computer programming, parametric design and rapid prototyping and environmental simulation, aiming to provided directed specialist support whenever required. Copyright © 2011 John Wiley & Sons, Ltd.