44 research outputs found
Using Color in Machine Vision Systems for Wood Processing
Color information, already shown to be valuable in distinguishing wood surface features, should prove especially useful for future applications of machine vision in the wood products industry. This review provides investigators interested in such applications with the information necessary for understanding the benefits-and associated difficulties-of using color. Various standard color-measurement systems ("color spaces") are discussed. No one system has been completely successful, at least partly because simple physical measurements are difficult to correlate with a human observer's complex perception of color. Color video camera systems, designed with human viewers in mind, have the potential for machine vision applications, but certain system "features" (white balance, gamma or contour correction) could cause problems. Future applications, including detecting and classifying hard-to-identify defects and matching colors of wood components, will require careful choice of lighting geometry and source, camera system, and color space for the purpose at hand
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CLPLOSS : analyzing green-end veneer recovery and loss
This paper is a detailed description of a method for calculating and analyzing losses and recoveries in a veneer peeling/clipping operation. The method involves filming veneer sheets as they exit the clipper, digitizing this film, and using the digitized information in a computer analysis
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Fuelwood characteristics of northwestern conifers and hardwoods
This publication collates the published ranges of fuelwood characteristics for 33 conifer and 20 hardwood species in the Pacific Northwest. The following characteristics are covered: specific gravity, percent moisture content, higher heating value, and percent ash of wood and bark; percent bark by volume; and ultimate analysis (percent carbon, hydrogen, oxygen, nitrogen, and sulfur) of wood and bark
Baseline characteristics of patients in the reduction of events with darbepoetin alfa in heart failure trial (RED-HF)
<p>Aims: This report describes the baseline characteristics of patients in the Reduction of Events with Darbepoetin alfa in Heart Failure trial (RED-HF) which is testing the hypothesis that anaemia correction with darbepoetin alfa will reduce the composite endpoint of death from any cause or hospital admission for worsening heart failure, and improve other outcomes.</p>
<p>Methods and results: Key demographic, clinical, and laboratory findings, along with baseline treatment, are reported and compared with those of patients in other recent clinical trials in heart failure. Compared with other recent trials, RED-HF enrolled more elderly [mean age 70 (SD 11.4) years], female (41%), and black (9%) patients. RED-HF patients more often had diabetes (46%) and renal impairment (72% had an estimated glomerular filtration rate <60 mL/min/1.73 m2). Patients in RED-HF had heart failure of longer duration [5.3 (5.4) years], worse NYHA class (35% II, 63% III, and 2% IV), and more signs of congestion. Mean EF was 30% (6.8%). RED-HF patients were well treated at randomization, and pharmacological therapy at baseline was broadly similar to that of other recent trials, taking account of study-specific inclusion/exclusion criteria. Median (interquartile range) haemoglobin at baseline was 112 (106–117) g/L.</p>
<p>Conclusion: The anaemic patients enrolled in RED-HF were older, moderately to markedly symptomatic, and had extensive co-morbidity.</p>
Mapping neurotransmitter systems to the structural and functional organization of the human neocortex
Neurotransmitter receptors support the propagation of signals in the human brain. How receptor systems are situated within macro-scale neuroanatomy and how they shape emergent function remain poorly understood, and there exists no comprehensive atlas of receptors. Here we collate positron emission tomography data from more than 1,200 healthy individuals to construct a whole-brain three-dimensional normative atlas of 19 receptors and transporters across nine different neurotransmitter systems. We found that receptor profiles align with structural connectivity and mediate function, including neurophysiological oscillatory dynamics and resting-state hemodynamic functional connectivity. Using the Neurosynth cognitive atlas, we uncovered a topographic gradient of overlapping receptor distributions that separates extrinsic and intrinsic psychological processes. Finally, we found both expected and novel associations between receptor distributions and cortical abnormality patterns across 13 disorders. We replicated all findings in an independently collected autoradiography dataset. This work demonstrates how chemoarchitecture shapes brain structure and function, providing a new direction for studying multi-scale brain organization.</p
Chapitre 14: Phytopathogènes et stratégies de contrôle en aquaponie
peer reviewedAmong the diversity of plant diseases occurring in aquaponics, soil-borne
pathogens, such as Fusarium spp., Phytophthora spp. and Pythium spp., are the most
problematic due to their preference for humid/aquatic environment conditions.
Phytophthora spp. and Pythium spp. which belong to the Oomycetes pseudo-fungi
require special attention because of their mobile form of dispersion, the so-called
zoospores that can move freely and actively in liquid water. In coupled aquaponics,
curative methods are still limited because of the possible toxicity of pesticides and
chemical agents for fish and beneficial bacteria (e.g. nitrifying bacteria of the
biofilter). Furthermore, the development of biocontrol agents for aquaponic use is
still at its beginning. Consequently, ways to control the initial infection and the
progression of a disease are mainly based on preventive actions and water physical
treatments. However, suppressive action (suppression) could happen in aquaponic
environment considering recent papers and the suppressive activity already
highlighted in hydroponics. In addition, aquaponic water contains organic matter
that could promote establishment and growth of heterotrophic bacteria in the system
or even improve plant growth and viability directly. With regards to organic
hydroponics (i.e. use of organic fertilisation and organic plant media), these bacteria
could act as antagonist agents or as plant defence elicitors to protect plants from
diseases. In the future, research on the disease suppressive ability of the aquaponic
biotope must be increased, as well as isolation, characterisation and formulation of
microbial plant pathogen antagonists. Finally, a good knowledge in the rapid
identification of pathogens, combined with control methods and diseases monitoring,
as recommended in integrated plant pest management, is the key to an efficient
control of plant diseases in aquaponics.Cos
Evaluation of Laminated Veneer Lumber Tensile Strength Using Optical Scanning and Combined Optical-Ultrasonic Techniques
Nondestructive commercial ultrasonic grading provides laminated veneer lumber (LVL) manufacturers a means for sorting veneer based on average ultrasonic propagation time (UPT) and/or average dynamic modulus of elasticity (MOEd). However, little is known about the influence of veneer defects on strength properties of veneer and LVL. Including veneer defect and growth ring pattern measurements, obtained via optical scanning, was hypothesized to improve LVL static tensile strength (Ft) property predictions. Nondestructive and destructive testing of Douglas-fir (Pseudotsuga menziesii) veneer and LVL was performed to evaluate improvements in LVL Ft property predictions. Various models based solely on density, optical, ultrasonic, and combined system measurements were developed for LVL property predictions. LVL static Ft was best predicted (R2 1/4 0.65) with integrated optical and ultrasonic measurements (ie combined system model), which included average defect, growth ring pattern, and MOEd measurements from the LVL material. Results suggested improved LVL Ft predictions could be achieved by integrating ultrasonic and optical systems. Additionally, the optical model, which included average defect, growth ring, and density measurements, better explained the variation in LVL static Ft values (R2 = 0.58) compared with the MOEd (R2 = 0.51) and UPT (R2 = 0.31) models