Deriving consistent long-term vegetation information from AVHRR reflectance data using a cover-triangle-based framework

Long-term vegetation dynamics associated with climatic changes can be assessed using Advanced Very High Resolution Radiometer (AVHRR) red and near-infrared reflectance data provided that the data have been processed to remove the effects of non-target signal variability, such as atmospheric and sensor calibration effects. Here we present a new method that performs a relative calibration of reflectance data to produce consistent long-term vegetation information. It is based on a simple biological framework that assumes that the position of the vegetation cover triangle is invariant in reflectance space. This assumption is in fact an intrinsic assumption behind the commonly used Normalised Difference Vegetation Index (NDVI) and is violated when the NDVI is calculated from inadequately corrected reflectance data. In this new method, any temporal variability in the position of the cover triangle is removed by geometrically transforming the observed reflectance data such that two features of the triangle—the soil line and the dark point—are stationary in reflectance space. The fraction of Photosynthetically Active Radiation absorbed by vegetation (fPAR; 0.0-0.95) is then calculated, via the NDVI, from calibrated reflectances. This method was tested using two distinct, monthly AVHRR products for Australia: (i) the coarse-resolution, fully calibrated, partially atmospherically corrected PAL data (1981-1994); and (ii) the fine-resolution, fully calibrated, non-atmospherically corrected HRPT data (1992-2004). Results show that, in the 20-month period when the two datasets overlap (1992-1994), the Australia-wide, root mean square difference between the two datasets improved from 0.098 to 0.027 fPAR units. The calibrations have produced two approximately equivalent datasets that can be combined as a single input into time-series analyses. The application of this method is limited to areas that have a wide-enough variety of land-cover types so that the soil line and dark point are evident in the cover triangle in every image of the time-series. Another limitation is that the methodology performs only bulk, relative calibrations and does not remove the absolute effects of observation uncertainties. The simplicity of the method means that the calibration procedure can be easily incorporated into near-real-time operational remote-sensing environments. Vegetation information produced using this invariant-cover-triangle method is expected to be well suited to the analysis of long-term vegetation dynamics and change.     

Differential diagnosis of spall vs. cracks in the gear tooth fillet region: Experimental validation

This paper presents a technique to differentially diagnose two types of localized gear tooth faults: a spall and a crack in the gear tooth fillet region. These faults could have very different prognoses, but existing diagnostic techniques only detect the presence of localized tooth faults without being able to differentiate between a spall and a crack. The effects of spalls and cracks on the behaviour of gear assemblies were studied using static and dynamic simulation models. Changes in the kinematics of a pair of meshing gears due to a gear tooth fillet crack (TFC) and a tooth flank spall were compared using a static analysis model. The difference in the variation of the transmission error (TE) caused by the two faults reveals their characteristics. The effect of a tooth crack depends on the change in stiffness of the tooth while the effect of a spall is dominantly determined by the geometry of the fault. A technique has previously been proposed to detect spalls [M. EL Badaoui, J. Antoni, F. Guillet, J. Daniere, Use of the moving cepstrum integral to detect and localize tooth spalls in gears, Mechanical System and Signal Processing, 15 (5) (2001) 873–885; M. EL Badaoui, V. Cahouet, F. Guillet, J. Daniere P. Velex, Modelling and detection of localized tooth defects in geared systems, Transaction of ASME, 123 (2001) 422–430], using the cepstrum to detect a negative echo in the signal (from entry into and exit from the spall) and successfully performed differential diagnosis on the simulated vibration signals. While the result of the experimental study showed some differences from the result of the simulation study, the differential diagnosis was successfully performed based on the technique presented in this paper. Further investigation revealed non-linear gearmesh behaviour which was causing differences in the experimental and simulation model results.     

Just teasing: A conceptual analysis and empirical review.

Drawing on E. Goffman's concepts of face and strategic interaction, the authors define a tease as a playful provocation in which one person comments on something relevant to the target. This approach encompasses the diverse behaviors labeled teasing, clarifies previous ambiguities, differentiates teasing from related practices, and suggests how teasing can lead to hostile or affiliative outcomes. The authors then integrate studies of the content of teasing. Studies indicate that norm violations and conflict prompt teasing. With development, children tease in playful ways, particularly around the ages of 11 and 12 years, and understand and enjoy teasing more. Finally, consistent with hypotheses concerning contextual variation in face concerns, teasing is more frequent and hostile when initiated by high-status and familiar others and men, although gender differences are smaller than assumed. The authors conclude by discussing how teasing varies according to individual differences and culture. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mouse strain differences in apomorphine-induced behavior: An empirical and methodological study.

Evaluated the behavioral response to intraperitoneal apomorphine HCl (0.5–32 mg/kg) in BALB/cJ, CBA/J, and C57BL/6J male mice. Dose–response curves for each component of the drug-induced behavioral repertoire were derived, and effective dose-50 (the dose at which 50% of the Ss met or exceeded a given rating) and slope were calculated for each. This method of analysis allows for a more quantitative estimate of drug sensitivity. Behaviors assessed included grooming, sniffing, climbing, and gnawing. Although some strain differences were observed in the qualitative characteristics of the response, differences in actual drug sensitivity were significant only at the higher ratings. Findings are discussed in relation to methodological and analytical problems in previous strain-comparison experiments. (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Evaluation of Integrated Fixed Film Activated Sludge Wastewater Treatment Processes at High Mean Cells Residence Time and Low Temperatures

Suspended solids mean cells residence time (MCRT) and temperature are two key parameters for designing Integrated Fixed Film Activated Sludge (IFAS) wastewater treatment processes, as an alternative for achieving year-round nitrification. It has been demonstrated from both full-scale and bench-scale studies that IFAS can accomplish year-round nitrogen removal and denitrification in aerobic zones in winter when operated with suspended growth MCRTs less than the critical MCRT for nitrifiers, thus avoiding increasing reactor or clarifier volumes. The objective of this study was to investigate the performances of IFAS systems that were operated at relative high MCRT compared to nitrifier washout MCRT and low temperature for biological nutrient removal. The comparison between two IFAS systems with Accuweb media in both the anoxic and aerobic zones, and a conventional three zone biological nutrient nemoval (BNR) system was conducted at 10°C with a 10 day MCRT using the UCT/VIP configuration for both systems and feeding with Blacksburg domestic wastewater. Influent flow was split 50% to the first anaerobic reactor and 50% to the first anoxic reactor to enhance denitrification in one of IFAS systems and the conventional BNR control system whereas 100% of the influent flow was fed to the first anaerobic reactor in the other IFAS system. The data from this investigation indicated that the performances of the control and IFAS systems were insignificantly different under the experimental operating conditions for both biological nitrogen and biological phosphorus removal except for IFAS with integrated fixed film media in the anoxic zone and when 50% of the influent was added directly to the first anoxic reactor.     

Role of social competence in borderline essestial hypertension.

Examined the social competence of 22 male borderline hypertensives (aged 19–45 yrs) in relation to cardiovascular responsivity to a behavioral role-play test (RPT) of assertiveness. Ss were divided into 2 groups: one group experienced large increases in pulse pressure (PP) in response to social challenge (Group 1), while the other group showed small changes in PP (relatively equal rises in systolic and diastolic blood pressure) under the same stimulus condition (Group 2). These differential group patterns of cardiovascular response were specific to interpersonal stressors because the groups did not differ in reactivity to cognitive challenges. Group 2 Ss evidenced unassertive responding on a role-play test of negative assertion and were rated by significant others as the least socially competent as compared to normotensive controls (who received the highest social competence ratings) and Ss in Group 1. Group 1 Ss responded in an inappropriately assertive fashion on the RPT and had shorter response latencies during the RPT than Ss in Group 2, suggesting that Ss in Group 2 had greater levels of interpersonal anxiety. Findings indicate that hostile inappropriate assertiveness and inappropriate submissiveness may be associated with hypertension. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

在新计算机的BIOS中可以找到什么

尽管BIOS经常被大家所忽视,不过它可以决定你新买的计算机的潜力。 作为有经验的计算机用户,当你购买计算机时免不了要问诸如什么类型的CPU、硬盘的大小和速度、内存和显存的大小以及插槽和驱动器架的数量之类的问题。然而,经常被遗漏就是BIOS。 BIOS插在计算机的主板上,可它却不是和主板一同生产的。如果你在两到三台计算机之间举棋不定,那么就值得看一下BIOS了。问几个有关BIOS的问     

The critical role of conflict resolution in teams: A close look at the links between conflict type, conflict management strategies, and team outcomes.

[Correction Notice: An erratum for this article was reported in Vol 93(2) of Journal of Applied Psychology (see record 2008-02855-019). Figure 2 on p. 184 (Theoretical Contributions section) is missing information about the numbers of teams and statements for the two groups using particularlistic strategies. For the decreasing and consistently low performance/decreasing and consistently low satisfaction group, there were 14 teams and 40 statements; for the decreasing and consistently low performance/increasing and consistently high satisfaction group, there were 11 teams and 46 statements.] This article explores the linkages between strategies for managing different types of conflict and group performance and satisfaction. Results from a qualitative study of 57 autonomous teams suggest that groups that improve or maintain top performance over time share 3 conflict resolution tendencies: (a) focusing on the content of interpersonal interactions rather than delivery style, (b) explicitly discussing reasons behind any decisions reached in accepting and distributing work assignments, and (c) assigning work to members who have the relevant task expertise rather than assigning by other common means such as volunteering, default, or convenience. The authors' results also suggest that teams that are successful over time are likely to be both proactive in anticipating the need for conflict resolution and pluralistic in developing conflict resolution strategies that apply to all group members. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Speed and accuracy of accessing information in working memory: An individual differences investigation of focus switching.

Three experiments examined the nature of individual differences in switching the focus of attention in working memory. Participants performed 3 versions of a continuous counting task that required successive updating and switching between counts. Across all 3 experiments, individual differences in working memory span and fluid intelligence were related to the accuracy of the counts, but not to the time cost associated with switching between counts. The authors suggest that working memory span and fluid intelligence measures partially index the ability to accurately switch information in and out of the focus of attention, but this variation is not related to the speed of switching. (PsycINFO Database Record (c) 2010 APA, all rights reserved)