Applicability of time-of-flight-based ground and multispectral aerial imaging for grapevine canopy vigour monitoring under direct root-zone deficit irrigation

ABSTRACT

This study investigates the applicability of ground-based 3D time-of-flight (ToF) imaging and small unmanned aerial system (UAS) integrated multispectral imaging as a rapid grapevine canopy vigour mapping tool for decision support during crop production management. Direct root-zone deficit irrigation was applied to grapevines with continuous and pulse irrigation techniques at 15%, 30%, and 60% rates as that of standard irrigation rate (100%) established by the grower in a commercial production. The control block was irrigated continuously at 100% standard irrigation rate. Field plots were imaged using ground platform integrated with 3D ToF imaging sensor and small UAS-integrated multispectral camera at 128 and 65 days before the harvest to estimate the canopy vigour variability associated with irrigation treatments. Customized as well as standard methods (convex hull and voxel grid) were utilized to extract canopy attributes (e.g. volume) from the 3D ToF imaging sensor data. The multispectral images were processed to extract normalized and green normalized difference vegetation index images. Resulting data were used to estimate canopy area ratio i.e. the ratio between the grapevine canopy area with respect to the total area in selected region of interest. A significant correlation (r = 0.34) between canopy volume estimated by customized algorithm and aerial canopy area ratio was observed. Custom canopy volume estimates were also highly correlated (r = 0.79) with voxel grid derived canopy volume data. Overall, 60% continuous direct root zone deficit irrigation appeared to produce canopy volume/vigour comparable with those under control treatment. Results also suggest that grower can utilize either or both (ground and aerial) grapevine canopy mapping techniques for effective management.     

Social identity,safety climate and self-reported accidents among construction workers

The construction industry has one of the highest frequencies of work-related accidents. We examined whether construction workers predominantly identify themselves in terms of their workgroup or in terms of the construction site. In addition, we examined the associations between social identity and safety climate, and how these constructs are associated with work-related accidents. The analyses were based on questionnaire responses from 478 construction workers from two large construction sites, and the methods involved structural equation modeling. Results showed that the workers identified themselves primarily with their workgroup, and to a lesser degree with the construction site. Social identity and safety climate were related both at the workgroup and construction site levels, meaning that social identity may be an antecedent for safety climate. The association between social identity and safety climate was stronger at the workgroup level than at the construction site level. Finally, safety climate at both levels was inversely associated with self-reported accidents, with the strongest association at the workgroup level. A focus on improving safety climate, particularly by integrating initiatives at both the workgroup and management level, may have the potential to improve safety performance and thus decrease the risk of accidents and injuries on construction sites.     

Parental divorce during early adolescence in Caucasian families: The role of family process variables in predicting the long-term consequences for early adult psychosocial adjustment.

The relationship between parental divorce occurring during adolescence and young adult psychosocial adjustment was examined, as was the role of family process variables in clarifying this relationship. Participants were young Caucasian adults from divorced (n?=?119) and married (n?=?123) families. Assessments were conducted during adolescence and 6 years later during early adulthood. Young adults from married families reported more secure romantic attachments than those from divorced families; however, differences were not evident in other domains of psychosocial adjustment after demographic variables were controlled. Three family process variables (parent–adolescent relationship, interparental conflict, and maternal depressive symptoms) were examined as potential mediators and moderators of the association between parental divorce and young adult adjustment. No evidence supporting mediation or moderation was found; however, the parent–adolescent and parent–young adult relationships, particularly when the identified parent was the father, emerged as significant predictors of young adult psychosocial adjustment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Carbon losses from soil and its consequences for land-use management

This paper reviews our current knowledge and understanding of carbon processes in the terrestrial ecosystem with a view to reducing soil carbon losses by optimising land-use and land management. Processes that influence the fate of carbon (in both terms of quantity and quality) are important in determining soil fertility, quality and health as well as consequences for future environmental change scenarios. We need to understand the processes that determine soil carbon losses and the fate of the carbon once lost from the soil in order to provide sustainable solutions for mitigating these carbon losses as part of land management "best practice" and balancing national carbon budgets. Here we review the amount of carbon within the UK terrestrial pool, the processes involved and factors influencing carbon transport to and from soils, the fate of the carbon once it has been lost from the soil environment and land-use scenarios that affect carbon losses. We conclude with possible management options to reduce soil carbon loss and identify gaps in knowledge in order to better understand carbon processes in the terrestrial environment.     

实现软件与硬件的真正协同

设计师们正在对一些新的设计方法进行评估，以期加快设计周期，缓解因新产品上市时间日趋加快带来的前所未有的重压。其中所建议使用的加速SoC设计周期的方法之一是硬件/软件的协同设计。拥有一种功能强大的协同设计工具可使设计理念大幅提升到系统级，从而改善硬件和软件设计小组之间的信息交流。同时它的使用还能有效地保护在RTL设计实现流程方面的现有投资。一些厂家已宣布，采用硬件/软件协同设计技术已使其设计时间减少一半，生产效率大为提高。那么，什么是真正的硬件/软件协同设计，它对设计小组又有怎样的意义？为此，本文将对硬…     

Atmospheric Effects on Compressive Creep of SiC-Whisker-Reinforced Alumina

A SiC-whisker-reinforced alumina composite was crept in compression at 1200° to 1400°C in an air ambient and in nitrogen. The data were described by a power-law-type constitutive relation. The measured value of the stress exponent was n = 1 at 1200°C and n = 3 at 1300° and 1400°C in both ambients. TEM observations were correlated with the measured creep response to determine active deformation mechanisms. Values of n = 1 were associated with diffusional creep and unaccommodated grain-boundary sliding, while values of n = 3 were associated with increased microstructural damage in the form of cavities. Experiments conducted in circulated air resulted in higher creep rates than comparable experiments in nitrogen. The accelerated creep rates were caused by the thermal oxidation of SiC and the resultant formation of a vitreous phase along composite interfaces. The glassy phase facilitated cavitation, weakened interfaces, and enhanced boundary diffusion.     

Syntheses of 12-aminododecanoic and 11-aminoundecanoic acids from vernolic acid

12-Aminododecanoic acid and 11-aminoundecanoic acid, monomer precursors for nylon-12 and nylon-11, respectively, have been synthesized from vernolic (cis-12,13-epoxy-cis-9-octadecenoic) acid via a reaction sequence that includes the formation of 12-oxododecanoic acid oxime. Saponification of vernonia oil, followed by a low-temperature recrystallization at −20°C, gave 51% vernolic acid (97% purity, m.p. 23–25°C). Hydrogenation afforded cis-12,13-epoxystearic acid (m.p. 52–54°C, lit. m.p. 52–54°C), which upon oxidation with periodic acid in tertiary butyl alcohol gave 12-oxododecanoic acid with an isolated yield of 71.0%. Reaction of the oxoacid with hydroxylamine hydrochloride gave 12-oxododecanoic acid oxime, which was catalytically reduced to give 12-aminododecanoic acid with a yield greater than 85% and a melting point of 184–186°C (lit. m.p. 185–187°C). 11-Aminoundecanoic acid was prepared from the 12-oxododecanoic acid oxime via a three-step reaction sequence that involved a Beckmann rearrangement, Hofmann degradation, and hydrolysis. Thus, the aldoxime acid was hydrolyzed in the presence of nickel acetate tetrahydrate to give 11-carbamoylundecanoic acid (48% yield, m.p. 129–131°C, lit. m.p. 129–130°C). The amide was then treated with a solution of sodium methoxide and bromine at 70–80°C to give 11-(methoxycarbonylamino)undecanoic acid at 75% yield (m.p. 84–86°C; elemental analysis, calculated for C₁₃H₂₅NO₄: C, 60.19; H, 9.73; N, 5.40; O, 24.68%; found C, 60.02; H, 9.81; N, 5.26; O, 24.91%), which upon alkaline hydrolysis and subsequent neutralization gave 11-aminoundecanoic acid at 34% yield (m.p. 189–192°C, lit. m.p. 190°C). Mass spectrometric and ¹³C nuclear magnetic resonance data of the previously unreported 11-(methoxycarbonylamino)undecanoic acid is provided.     

Innovations in Large-Scale Supported Distance Teaching: Transformation for the Internet,Not Just Translation

This paper reports on large-scale trials of Internet-based university-level distance teaching. The use of technology, and more specifically the Internet, has been an important advance for distance education. However, simply translating material from familiar media into electronic form is rarely productive—and is certainly inadequate for supported distance education, which aims to engage the student in a “community of learning.” The value Internet technology brings to distance education lies not in direct translation from other media but in transformation of support mechanisms to exploit its potential range. The paper addresses how instruction and support functions can be served and potentially enhanced by an Internet-based structure. It considers which changes in culture help to preserve or improve teaching quality while adapting to screen-based and often asynchronous interactions. It discusses our trials of mechanisms for interactions among students and tutors; assignment marking using an electronic marking tool; electronic assignment handling; synchronous and asynchronous Internet-based problem sessions; and automatic student registration. The paper summarizes qualitative and quantitative findings of an extensive evaluation involving several hundred students over three courses and considering learning, student experience, assignment marking, problem sessions, scalability, and integration into existing administrative structures. It highlights both costs and gains of using the Internet to transform the distance learning environment for those associated with it: students, tutors, administrators, and institutions.