Pure Significance Tests of the Unit Root Hypothesis Against Nonlinear Alternatives

Abstract. This paper describes artificial neural network based pure significance tests for the unit root hypothesis against nonlinear alternatives. The theoretical properties of the tests are discussed and a Monte Carlo investigation of their small sample properties is undertaken.     

Heating Characteristics of Homogeneous Milk-Based Formulas in Cans Processed in an Agitating Retort

Milk-based formulas with proximate analyses similar to infant formulas were heated to determine influence of headspace, reel speed, solids content, and consistency on F_o. Concentrations with 12.5, 25, and 30% solids were heated in three can sizes. Increasing Steritort rpm from 3.4 to 10.9 for 307 × 710 cans (12.5% solids) had greatest effect; the F_o increased from 9.8 to 12.3. The same increase in rpm for a continuous retort would reduce F_o from 9.8 to 2.0 because of reduced processing time. Solids content and consistency influenced heating, but variations in consistency of a given concentration had no measurable effect on F_o. Headspace influenced heating for each concentration, but was not as critical as for more viscous products.     

A City Metaphor to Support Navigation in Complex Information Spaces

A major problem in modern information systems is to locate information and to re-find information one has seen before. Systems like the World Wide Web are heavily interlinked, but do not show structures that help users to navigate the information it contains. The use of appropriate navigation metaphors can help to make the structure of modern information systems easier to understand and therefore easier to use.We propose a conceptual user interface metaphor based on the structure of a city. Cities are very complex spatial environments and people know how to get information, how to reach certain locations in a city, and how to make use of the available infrastructure, etc. Cities provide a rich set of navigational infrastructure that lends itself to creating sub-metaphors for navigational tools. A city metaphor makes this existing knowledge about a structured environment available to the user of a computerized information system.We first focus on several properties necessary for future user interfaces (or user interface metaphors) that will distinguish them from current systems, like the richness of information or the use of visualizations to show the structure of information spaces. We also describe the strengths and problems of spatial user-interface metaphors. Then we present the structure of the information city metaphor, its structuring and navigation metaphors and what we see as its main advantages and problems. We further outline a few scenarios of how an Information City might work. Finally, we compare implementing this metaphor using either a textual or a graphical virtual environment or a combination.     

Strategic management control

Throughout this account, the growing interest in management strategy, as a subject which can be planned, as well as described, by upper-echelon managers has been indicated.

The most important concept that has been outlined is that the need for a planned management strategy arises directly from the task which management sets itself when it tries to control its environment. It is not merely a need which becomes apparent at a high level of management complexity, but is inherently part of the function of management.

The second important idea, implicit throughout this account, and made explicit in §7, is that models of the organization are baaed on axioms which must be outlined at the highest level of control in an organization—by the board of directors : thus, the board have a direct influence, as well as ultimate responsibility, in the modelling activities of managers who construct and carry out planned strategic decisions.     

MRP lot sizing with variable production/purchasing costs: formulation and solution

The research on lot sizing is extensive; however, no author in the literature reviewed to date provides an optimal solution algorithm to a prevalent problem which is found in manufacturing. A multi-level, general product-structure, variable-cost model is presented which follows the procedure of a closed-loop material requirements planning (MRP) system, and incorporates many conditions that production and material managers find in practice. A branch and bound (B&B7) algorithm is developed. The efficiency of B&B is derived from effective lower bounds and solution procedures which are determined on the basis of the space-time structure of the MRP lot-sizing problem and its non-convex total-cost function. This path-dependent lower bound is computationally efficient and guarantees an optimal solution. The B&B algorithm is tested on problems and compared to heuristics in the literature.     

The effects of market power on the stocks and prices of world coffee

The objective of this study is to explore the consequences of market power for optimal stockholding and price variations in the world coffee economy. Optimal storage decision rules which incorporate risk aversion under several market scenarios are considered. These generate a set of price and quantity series that can be compared with the historical data and to test the hypothesis proposed by Newbery that a monopolistic producer tends to undertake more storage than a competitive producer and hence price stability may increase in proportion to the dominant role played by the monopolist. Our study reveals that the world coffee market has been rather close to the competitive regime since the 1960s. As far as price variations are concerned, results are not always consistent with the Newbery hypothesis.     

Feedback information rate and entropy in a discrete system†

A multi-state deterministic system controlled via a noisy Binary Symmetric Channel (BSC) is modelled by an equivalent Markov chain. The system performs a random walk whose mean deviation from zero is numerically equal to the expected number of steps between zero crossings, and whose entropy is equal to the average amount of transmitted control information between zero crossings. Simple expressions are found for the received control information and for the mutual information via the BSC.     

EXTRUSION PROCESSING OF RICE OR CORN FLOUR WITH MECHANICALLY DEBONED TURKEY1

Rice flour and yellow or white corn flour were combined at 50, 60 and 70% levels with mechanically deboned turkey and extrusion processed at 104C and 121C. The texture of the extrudates was evaluated by Warner-Bratzler shear (WBS), and flour concentration had more effect on the WBS values than flour type; treatments with 70% flour had significantly greater WBS values. Corn flour treatments and low temperature extrusion resulted in greater TBA values. Proximate composition of extrudates confirmed moisture losses during extrusion and that high temperature processing had mixed results on ether-extractable compounds.     

Aldehydes, Ketones and Esters in Valencia Orange Peel Oil

SUMMARY: The aldehydes, ketones and esters in the volatile portion of Valencia orange oil have been isolated and identified. Seventeen aldehydes and ketones and three esters are included, 10 of which have never been identified as constituents of Valencia oil. Cis- and trans-limonene oxide have also been found to occur in the same fraction. This is the first time that these compounds have been identified in cold-pressed orange oil. A series of five homologous α,β-unsaturated aldehydes were isolated and partially characterized.