Sources of Variation and Performance of Nine Devices When Measuring Percent Residue Cover

1995 ◽  
Vol 38 (2) ◽  
pp. 521-529 ◽  
Author(s):  
J. E. Morrison Jr. ◽  
J. Lemunyon ◽  
H. C. Bogusch Jr.
2002 ◽  
Vol 53 (1) ◽  
pp. 41 ◽  
Author(s):  
R. A. Richards ◽  
Z. Lukacs

The early growth of wheat is slow compared with that of barley and triticale. This is expected to limit the yield of wheat in environments where greater seedling vigour is advantageous. To overcome the slow growth of wheat, genetic sources of seedling vigour are required for use in breeding programs, and/or ways to increase seedling growth by manipulating seed characteristics. This study reports (i) new sources of and 3 heights at cutting (cutting was done when the grass reached 0.5, 1, and 1.5 m above the ground). The N fertiliser treatment did not yield any significant difference in DMD, ND, or IVDMD. Height at cutting had a significant (P < 0.05) effect on rumen DMD and ND and their degradability characteristics for all incubation times. There was a reduction in DMD and ND and their degradability characteristics as plant height increased at cutting. Similarly, as height at cutting increased there was a decline in IVDMD. There was a positive linear correlation between IVDMD and both DMD and ND at 48, 72, 96, and 120 h (r = 0.917, 0.923, 0.921, and 0.850 for DMD; r = 0.795, 0.814, 0.787, and 0.787 for ND). Hence, further study on intake and performance of animals is suggested to develop Napier-based diets for smallholders.


2021 ◽  
Author(s):  
◽  
Barbara Elisabeth Alexandra Korte

This dissertation explores the breadth and variation of authoritarian counter-terrorism strategies and their legitimacy-related origins to challenge prevailing assumptions in Terrorism Studies. Research and analysis are conducted in the form of a Structured Focused Comparison of domestic counter-terrorism strategies in two electoral autocracies. The first case is Russia’s domestic engagement against a mix of ethno-separatist and Islamist terrorism emanating from its North Caucasus republics between 1999 and 2018. The second case is China’s engagement vis-à-vis a similar type of terrorism in its Xinjiang Uyghur Autonomous Region between 1990 and 2018. The comparison shows that, contrary to prevailing assumptions, the two strategies differ immensely from one another while containing significant if not predominant non-coercive elements. It further shows that the two strategies are closely related to the two states’ sources and resources of legitimacy, both in their original motivation to tackle the terrorist threat and in the design of counter-terrorism strategies. Drawing on David Beetham’s theory of The Legitimation of Power and on the Comparative Politics, Terrorism Studies and Civil War literatures, the dissertation explores the influence of five sources and (re)sources of legitimacy on the two counter-terrorism strategies: responsiveness, performance legitimacy, ideology, discursive power and co-optation. While governmental discursive power is discarded as a source of variation, findings are significant with respect to the influence of ideology and performance legitimacy. Reliance on ideology or related patterns for legitimation raise vulnerability to terrorism and constrain or facilitate the adoption of communicative and preventive measures that accommodate the grievances of potentially defective or even violently terrorist groups. Performance legitimacy is a key motivator in counter-terrorism and an influence on certain types of counter-terrorism policies. Responsiveness and co-optation are identified as potential sources of variation, based on idiosyncratic concurrence with policy choices.


1988 ◽  
Vol 111 (2) ◽  
pp. 407-410 ◽  
Author(s):  
O. O. Oni ◽  
V. Buvanendran ◽  
N. I. Dim

Birth weight and pre-weaning performance are recognized as important components in determing economic returns from beef cattle. The accuracy of ranking animals based on their breeding values, and hence the effectiveness of selection, will be increased when allowance is made for non-genetic sources of variation. Furthermore, the proper evaluation of identifiable sources of variation in calf weaning weight aids in more accurate appraisal of genetic differences in mothering ability among beef cows.


Author(s):  
Jaime A. Camelio ◽  
S. Jack Hu ◽  
Dariusz J. Ceglarek

Abstract Products made of compliant sheet metals are widely used in automotive, aerospace, appliance and electronics industries. One of the most important challenges for the assembly process of such compliant parts is the assembly dimensional quality, which affects product functionality and performance. This paper develops a methodology to evaluate the dimensional variation propagation in a multi-station compliant assembly system based on linear mechanics and a state space representation. Three sources of variation are analyzed, part variation, fixture variation and weld gun variation. The proposed method is illustrated through a case study on automotive body assembly.


2003 ◽  
Vol 125 (4) ◽  
pp. 673-681 ◽  
Author(s):  
Jaime Camelio ◽  
S. Jack Hu ◽  
Dariusz Ceglarek

Products made of compliant sheet metals are widely used in automotive, aerospace, appliance and electronics industries. One of the most important challenges for the assembly process with compliant parts is dimensional quality, which affects product functionality and performance. This paper develops a methodology to evaluate the dimensional variation propagation in a multi-station compliant assembly system based on linear mechanics and a state space representation. Three sources of variation: part variation, fixture variation and welding gun variation are analyzed. The proposed method is illustrated through a case study on an automotive body assembly process.


Author(s):  
H. M. Thieringer

It has repeatedly been show that with conventional electron microscopes very fine electron probes can be produced, therefore allowing various micro-techniques such as micro recording, X-ray microanalysis and convergent beam diffraction. In this paper the function and performance of an SIEMENS ELMISKOP 101 used as a scanning transmission microscope (STEM) is described. This mode of operation has some advantages over the conventional transmission microscopy (CTEM) especially for the observation of thick specimen, in spite of somewhat longer image recording times.Fig.1 shows schematically the ray path and the additional electronics of an ELMISKOP 101 working as a STEM. With a point-cathode, and using condensor I and the objective lens as a demagnifying system, an electron probe with a half-width ob about 25 Å and a typical current of 5.10-11 amp at 100 kV can be obtained in the back focal plane of the objective lens.


Author(s):  
Huang Min ◽  
P.S. Flora ◽  
C.J. Harland ◽  
J.A. Venables

A cylindrical mirror analyser (CMA) has been built with a parallel recording detection system. It is being used for angular resolved electron spectroscopy (ARES) within a SEM. The CMA has been optimised for imaging applications; the inner cylinder contains a magnetically focused and scanned, 30kV, SEM electron-optical column. The CMA has a large inner radius (50.8mm) and a large collection solid angle (Ω > 1sterad). An energy resolution (ΔE/E) of 1-2% has been achieved. The design and performance of the combination SEM/CMA instrument has been described previously and the CMA and detector system has been used for low voltage electron spectroscopy. Here we discuss the use of the CMA for ARES and present some preliminary results.The CMA has been designed for an axis-to-ring focus and uses an annular type detector. This detector consists of a channel-plate/YAG/mirror assembly which is optically coupled to either a photomultiplier for spectroscopy or a TV camera for parallel detection.


Author(s):  
Joe A. Mascorro ◽  
Gerald S. Kirby

Embedding media based upon an epoxy resin of choice and the acid anhydrides dodecenyl succinic anhydride (DDSA), nadic methyl anhydride (NMA), and catalyzed by the tertiary amine 2,4,6-Tri(dimethylaminomethyl) phenol (DMP-30) are widely used in biological electron microscopy. These media possess a viscosity character that can impair tissue infiltration, particularly if original Epon 812 is utilized as the base resin. Other resins that are considerably less viscous than Epon 812 now are available as replacements. Likewise, nonenyl succinic anhydride (NSA) and dimethylaminoethanol (DMAE) are more fluid than their counterparts DDSA and DMP- 30 commonly used in earlier formulations. This work utilizes novel epoxy and anhydride combinations in order to produce embedding media with desirable flow rate and viscosity parameters that, in turn, would allow the medium to optimally infiltrate tissues. Specifically, embeding media based on EmBed 812 or LX 112 with NSA (in place of DDSA) and DMAE (replacing DMP-30), with NMA remaining constant, are formulated and offered as alternatives for routine biological work.Individual epoxy resins (Table I) or complete embedding media (Tables II-III) were tested for flow rate and viscosity. The novel media were further examined for their ability to infilftrate tissues, polymerize, sectioning and staining character, as well as strength and stability to the electron beam and column vacuum. For physical comparisons, a volume (9 ml) of either resin or media was aspirated into a capillary viscocimeter oriented vertically. The material was then allowed to flow out freely under the influence of gravity and the flow time necessary for the volume to exit was recored (Col B,C; Tables). In addition, the volume flow rate (ml flowing/second; Col D, Tables) was measured. Viscosity (n) could then be determined by using the Hagen-Poiseville relation for laminar flow, n = c.p/Q, where c = a geometric constant from an instrument calibration with water, p = mass density, and Q = volume flow rate. Mass weight and density of the materials were determined as well (Col F,G; Tables). Infiltration schedules utilized were short (1/2 hr 1:1, 3 hrs full resin), intermediate (1/2 hr 1:1, 6 hrs full resin) , or long (1/2 hr 1:1, 6 hrs full resin) in total time. Polymerization schedules ranging from 15 hrs (overnight) through 24, 36, or 48 hrs were tested. Sections demonstrating gold interference colors were collected on unsupported 200- 300 mesh grids and stained sequentially with uranyl acetate and lead citrate.


Author(s):  
D. E. Newbury ◽  
R. D. Leapman

Trace constituents, which can be very loosely defined as those present at concentration levels below 1 percent, often exert influence on structure, properties, and performance far greater than what might be estimated from their proportion alone. Defining the role of trace constituents in the microstructure, or indeed even determining their location, makes great demands on the available array of microanalytical tools. These demands become increasingly more challenging as the dimensions of the volume element to be probed become smaller. For example, a cubic volume element of silicon with an edge dimension of 1 micrometer contains approximately 5×1010 atoms. High performance secondary ion mass spectrometry (SIMS) can be used to measure trace constituents to levels of hundreds of parts per billion from such a volume element (e. g., detection of at least 100 atoms to give 10% reproducibility with an overall detection efficiency of 1%, considering ionization, transmission, and counting).


1986 ◽  
Vol 50 (5) ◽  
pp. 264-267 ◽  
Author(s):  
GH Westerman ◽  
TG Grandy ◽  
JV Lupo ◽  
RE Mitchell

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