7,338 research outputs found
Poultry Farming in the Coastal Agro Ecosystem of Kerala
The potential for development
of the coastal agro eco system
through supplementary occupation
has not yet been fully realized.
The people living the coastal
areas are among the poorest in
the world. Poor water and soil
quality, diseases and social
backwardness are the other
reasons for unsuccessful
development. Though aquaculture
has got great scope for
generation of wealth and
enhanced per capita income,
consistent results are not
obtained due to fish diseases and
inappropriate management at farm
level
Validation of the Standardized and Simplified Cutting Bill
This research validated the framework for the standardized and simplified cutting bill presented in an earlier paper. The cutting bill validation was carried out in two ways. First, all 20 of the cutting bill's part groups were examined to determine if significant yield influences resulted from changing specific part sizes within the boundaries of a given part group. Second, five cutting bills from industrial operations were fit into the framework of the cutting bill, and the simulated yields from these industrial cutting bills were compared with the fitted cutting bills. Yield differences between the two were calculated and tested for significance. Tests revealed that the standardized and simplified cutting bill framework performed as designed. The maximum yield difference observed was 2% and the average less than 1%. Clustering the industrial cutting bill part requirements according to the cutting bill framework led to an average absolute yield deviation between the original cutting bills and the clustered cutting bills of 3.25%. These results show while cutting bill part-size requirements can be clustered into part groups, yield differences of a certain magnitude are introduced by so doing
Estimating Small Area Income Deprivation: An Iterative Proportional Fitting Approach
Small area estimation and in particular the estimation of small area income deprivation has
potential value in the development of new or alternative components of multiple deprivation
indices. These new approaches enable the development of income distribution threshold based
as opposed to benefit count based measures of income deprivation and so enable the
alignment of regional and national measures such as the Households Below Average Income
with small area measures. This paper briefly reviews a number of approaches to small area
estimation before describing in some detail an iterative proportional fitting based spatial
microsimulation approach. This approach is then applied to the estimation of small area HBAI
rates at the small area level in Wales in 2003-5. The paper discusses the results of this
approach, contrasts them with contemporary ‘official’ income deprivation measures for the
same areas and describes a range of ways to assess the robustness of the results
The Influence of Cutting-Bill Requirements on Lumber Yield Using a Fractional-Factorial Design Part II. Correlation and Number of Part Sizes
Cutting-bill requirements, among other factors, influence the yield obtained when cutting lumber into parts. The first part of this 2-part series described how different cutting-bill part sizes, when added to an existing cutting-bill, affect lumber yield, and quantified these observations. To accomplish this, the study employed linear least squares estimation technique. This second paper again looks at the influence of cutting-bill requirements but establishes a measure of how preferable it is to have a given part size required by the cutting-bill. The influence of the number of different part sizes to be cut simultaneously on lumber yield is also investigated.Using rip-first rough mill simulation software and an orthogonal, 220-11 fractional-factorial design of resolution V, the correlation between lengths, widths, and 20 part sizes as defined by the Buehlmann cutting-bill with high yield was established. It was found that, as long as the quantity of small parts is limited, part sizes larger than the smallest size are more positively correlated with high yield. Furthermore, only 4 out of the 20 part sizes tested were identified with having a significant positive correlation with above average yield (65.09%), while 10 were found with a significant negative correlation and above average yield. With respect to the benefit of cutting varying numbers of part sizes simultaneously, this study showed that there is a positive correlation between yield and the number of different part sizes being cut. However, Duncan's test did not detect significant yield gains for instances when more than 11 part sizes are contained in the cutting-bill
Creating A Standardized and Simplified Cutting Bill Using Group Technology
From an analytical viewpoint, the relationship between rough mill cutting bill part requirements and lumber yield is highly complex. Part requirements can have almost any length, width, and quantity distribution within the boundaries set by physical limitations, such as maximum length and width of parts. This complexity makes it difficult to understand the specific relationship between cutting bill requirements and lumber yield, rendering the optimization of the lumber cutting process through improved cutting bill composition difficult.An approach is presented to decrease the complexity of cutting bills to allow for easier analysis and, ultimately, to optimize cutting bill compositions. Principles from clustering theory were employed to create a standardized way to describe cutting bills. Cutting bill part clusters are part groups within the cutting bill's total part size space, where all parts are reset to a given group's midpoint. Statistical testing was used to determine a minimum resolution part group matrix that had no significant influence on yield compared to an actual cutting bill.Iterative search led to a cutting bill part group matrix that encompasses five groups in length and four groups in width, forming a 20-part group matrix. The lengths of the individual part groups created vary widely, with the smallest group being only 5 inches in length, while the longest two groups were 25 inches long. Part group widths were less varied, ranging from 0.75 inches to 1.0 inch. The part group matrix approach allows parts to be clustered within given size ranges to one part group midpoint value without changing cut-up yield beyond set limits. This standardized cutting bill matrix will make the understanding of the complex cutting bill requirements-yield relationship easier in future studies
The Influence of Cutting-Bill Requirements on Lumber Yield Using a Fractional-Factorial Design Part I. Linearity and Least Squares
The importance of lumber yield on the financial success of secondary solid wood products manufacturers has been known for quite some time. Various efforts have been undertaken to improve yield, such as inclusion of character marks (defects) in parts, "cookie-cutting" of boards, improved optimization algorithms, or improved cut-up technologies. For a variety of reasons, the relationship between cutting-bill requirements and lumber yield has attracted limited attention. This is Part I of a 2-part examination of this relationship.The standardized and simplified Buehlmann cutting bill and the Forest Service's Romi-Rip lumber cut-up simulator were used in this study. An orthogonal, 220-11 fractional-factorial design of resolution V was used to determine the influence of different part sizes on lumber yield. All 20 part sizes contained in the cutting bill and 113 of a total of 190 unique secondary interactions were found to be significant variables in explaining the variability in observed yield. Parameter estimates for the part sizes and the secondary interactions were used to specify the average yield contribution of each variable. Parts 445 mm long and 64 mm wide were found to have the most positive influence on yield. Parts smaller than 445 by 64 mm (such as, for example 254 by 64 mm) had a less pronounced positive yield effect because their quantity requirement is relatively small in an average cutting bill. Thus, the quantity required is obtained quickly during the cut-up process. Parts with size 1842 by 108 mm, on the other hand, had the most negative influence on high yield. However, as further analysis showed, not only the individual parts required by a cutting bill, but also their interaction determines yield. In general, it was found that by adding a sufficiently large number of smaller parts to a cutting bill that required large parts, high levels of yield can be achieved
Robustness of the Blandford-Znajek mechanism
The Blandford-Znajek mechanism has long been regarded as a key ingredient in
models attempting to explain powerful jets in AGNs, quasars, blazzars etc. In
such mechanism, energy is extracted from a rotating black hole and dissipated
at a load at far distances. In the current work we examine the behaviour of the
BZ mechanism with respect to different boundary conditions, revealing the
mechanism robustness upon variation of these conditions. Consequently, this
work closes a gap in our understanding of this important scenario.Comment: 7 pages, accepted in CQ
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