101 results for Report, 1997

  • Recent Developments in Organic Food Production in New Zealand: Part 2: Kiwifruit in the Bay of Plenty

    Campbell, Hugh; Fairweather, John; Steven, David (1997)

    Report
    University of Otago

    This report presents the findings of research into the development of organic kiwifruit production in the Bay of Plenty. These results form the second of four case studies which constitute the Public Good Science Fund programme ‘Optimum Development of Certified Organic Horticulture in New Zealand’. The other case study regions are Canterbury (Campbell 1996), Gisborne (to be completed during 1997) and Nelson (to be completed by 1998). The primary objective of this report is to document developments in the organic export industry in the Bay of Plenty. Comparisons between Canterbury and the Bay of Plenty have occasionally been included in this report in order to provide more clarity about the development of organic production in the Bay of Plenty itself. While there is some discussion of the differences between Canterbury and the Bay of Plenty in the Conclusion, these are only brief. Full comparison of the regional factors influencing the development of organic exporting will be set aside until all four case studies have been completed.

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  • Stratigraphy and reserves of pumiceous sand deposits in Perry's 'Asparagus Block' at Horotiu

    Nelson, Campbell S.; Lowe, David J.; Lootsma, A (1997)

    Report
    University of Waikato

    The stratigraphic relationships between the deposits of the Hinuera Formation and the Taupo Pumice Alluvium are described over a 16 ha plot of land known as the 'Asparagus Block' at Horotiu. The Hinuera Formation is exposed at the surface at the southern end of this block, and is overlain by a wedge of Taupo Pumice Alluvium which increases in thickness from 0 to 8 m northwards across the block. Lithofacies in the Hinuera Formation are dominated by trough cross-bedded gravelly sands (lithofacies AI), with common cross-laminated sands (lithofacies B) and massive to horizontally laminated silts (lithofacies D). The pumice content of these deposits is mainly 70%. Lithofacies in the Taupo Pumice Alluvium are dominated by horizontally to inclined (tabular cross-) bedded slightly gravelly sands and sands (lithofacies G 1/2), with common occurrences of horizontally bedded to massive sandy silts (lithofacies D). The pumice content of these Taupo deposits is high, typically >80%. Cross-sections are presented showing an interpreted subsurface distribution of these lithofacies from south to north through the 'Asparagus Block'. The estimated reserve of extractable pumice sand from the block is of the order of about 400,000 to 450,000 m³.

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  • Soil-landscape modelling and soil property variability for forestry land evaluation in Longwood Forest, Southland. Phase 1: soil-landscape model development

    Jones, Hayden S.; Lowe, David J.; McLay, C.D.A. (1997)

    Report
    University of Waikato

    Large scale, quantitative information about the variability of target soil properties is required for forest management. This project is attempting to determine whether or not the New Zealand Soil Classification system (NZSC), when used in combination with a soillandscape model, adequately communicates this information. In the first phase of this project a soil-landscape model was developed and a pilot variability study conducted. The soils in the study area, located in the W oodlaw Block of the Longwood Range, are formed from either Permian andesite or greywacke on moderately steep to steep hill slopes under a moist cool climate and a vegetation cover of beech and podocarp forests. The soil-landscape model was developed using the land systems approach. The model consists of predictive relationships between topographic features and soil classes. There is a clear relationship between slope steepness, the abundance of surface boulders and the gravel content of the soil. A soil-landscape unit map showing the distribution of predicted soil classes has been produced. The results of the pilot variability study have showed that the soils sampled are acidic and have moderate to high P-retention values. An analysis of variance indicated that both of these properties are significantly variable between sites and between horizons. There appears to be a relationship between land component type and the magnitude and variability of these properties. The clay mineralogical analysis revealed that the dominant clay minerals present in all the soils sampled are chlorite-vermiculite, kaolinite, sepiolite, and allophane. The presence of allophane and kaolinite may be related to the moderate to high P-retention values.

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  • Geoscientific reconnaisance of Perry Aggregates quarry, River Road, Horotiu

    Nelson, Campbell S.; Lowe, David J. (1997)

    Report
    University of Waikato

    At the request of David Jennings, Opus International Consul tan ts Ltd, Hamil ton, we visited the Perry Aggregates quarry on River Road, Horotiu, on the morning of Wednesday 23 April 1997 to comment on the geoscientific context of the quarry. Our specific remarks relate only to observations made at the pit face at the present northwestern extremity of the quarry, which nevertheless are probably appropriate for the quarry as a whole. The quarry area inspected lies on a low terrace about 8 m above present-day river level (about 15 m a.s.l.) immediately adjacent to the Waikato River and covers an area of about 180 x 250 m centred on approximate grid reference S14 029885 (1:50 000 topographic map series NZMS 260).

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  • A Genius' Story: Two Books on Godel

    Calude, C.S (1997-06)

    Report
    The University of Auckland Library

    Undoubtly, Gödel was the greatest logician of the twentieth century. There is no trace of exaggeration in saying, following Wang, that Gödel's contribution to mathematics has the same status as Freudian psychology, Einstein's theory of relativity, Bohr's principle of complementarity, Heisenberg's uncertainty principle, keynesian economics, and Watson and Crick double helix model of DNA. Yet, with a few notable exceptions, most of the personal details of Gödel's life remained a mystery

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  • Clusters of Two Player Games and Restricted Determinacy Theorem

    Khoussainov, B; Yakhnis, A; Yakhnis, V (1997-05)

    Report
    The University of Auckland Library

    We introduce a new notion of a cluster of infinite two player games between players 0 and 1. This is an infinite collection of games whose game trees can be composed into a graph which is similar to a tree except that the graph might not have the initial node. For each node of the graph there is an ancesstor node. We call this graph the arena of the cluster. For a game cluster we introduce a notion of a winner for the whole cluster. This notion is weaker than the requirement to win every game of the cluster. Any two player game can be viewed as a game cluster consisting of all its residual games [3, 18]. We extend the restricted memory determinacy (RMD) theorem of Gurevich-Harrington (GH), [3] to game clusters. We think that the notion of a game cluster improves the modeling power of two player games used to give semantics for concurrent processes [10, 11].

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  • DNA Computing Based on Splicing: Universality Results

    Paun, G (1997-12)

    Report
    The University of Auckland Library

    First, we recall some characterizations of recursively enumerable languages by means of finite H systems with certain regulations on the splicing operation. Then, we consider a variant of the splicing operation where the splicing proceeds always in couples of steps: the two strings obtained after a splicing enter immediately a second splicing (the rules used in the two steps are not prescribed). Somewhat surprising if we take into account the loose control on the performed operations, extended H systems with finite sets of axioms and of splicing rules, using this double splicing operation, can again characterize the recursively enumerable languages. Finally, we consider two types of distributed H systems: communicating distributed H systems and time-varying distributed H systems. For the first type of devices, we give a new proof of the recent result of [24] that (in the extended case) such systems with three components characterize the recursively enumerable languages. In what concerns the second mentioned distributed model, we prove that time-varying H systems with seven components can characterize the recursively enumerable languages. The optimality of these two last mentioned results is open.

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  • Effective Presentability of Boolean Algebras of Cantor-Bendixson Rank 1

    Downey, R.G; Jockusch Jr, C.G (1997-08)

    Report
    The University of Auckland Library

    We show that there is a computable Boolean algebra B and a computably enumerable ideal I of B such that the quotient algebra B=I is of Cantor-Bendixson rank 1 and is not isomorphic to any computable Boolean algebra. This extends a result of L. Feiner and is deduced from Feiner's result even though Feiner's construction yields a Boolean algebra of infinite Cantor-Bendixson rank.

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  • Deterministic Incomplete Automata: Simulation, Universality and Complementarity

    Calude, E; Lipponen, M (1997-06)

    Report
    The University of Auckland Library

    We study finite deterministic incomplete automata without initial states. This means that at any stage of a computation there is at most one transition to the next state. We will first investigate how two incomplete automata can simulate each other. Further on we construct an incomplete automaton which simulates a given automaton S and has the minimum number of states compared to any other automaton simulating S. Finally, we study Moore's uncertainty principles for incomplete automata. In contrast with the case of complete automata, it is possible to construct incomplete three-state automata displaying both types of complementarity.

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  • Some extended explicit Bel'tyukov pairs for Volterra integral equations of the second kind

    Sharp, P.W. (1997-04)

    Report
    The University of Auckland Library

    We derive and investigate a family of extended explicit Bel'tyukov (EBVRK) pairs for Volterra integral equations of the second kind. The pairs use six stages, and consist of an order 3 formula completely embedded in an order 4 formula. As part of the derivation, we show that at least 6 stages are needed to form such pairs. We also examine some aspects of the structure of EBVRK pairs.

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  • Geometry of Pseudospheres II.

    Marshall, T.H. (1997-03)

    Report
    The University of Auckland Library

    We investigate finite sequences of hyperplanes in a pseudosphere. To each such sequence we associate a square symmetric matrix, the Gram matrix, which gives information about angle and incidence properties of the hyperplanes. We find when a given matrix is the Gram matrix of some sequence of hyperplanes, and when a sequence is determined up to isometry by its Gram matrix. We also consider subspaces of pseudospheres and projections onto them. This leads to an n-dimensional cosine rule for spherical and hyperbolic simplices.

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  • A Constructive Proof of Gleason's Theorem

    Richman, F; Bridges, D.S (1997-05)

    Report
    The University of Auckland Library

    Gleason's theorem states that any totally additive measure on the closed subspaces, or projections, of a Hilbert space of dimension greater than two is given by a positive operator of trace class. In this paper we give a constructive proof of that theorem. A measure μ on the projections of a real or complex Hilbert space assigns to each projection P a nonnegative real number μ(P) such that if σ = ∑Pi, where the Pi are mutually orthogonal, then μ(σ) =∑μ(Pi). Such a measure is determined by its values on the one-dimensional projections. Let W be the measure of the identity projection, and Px the projection onto the 1-dimensional space spanned by the unit vector x. Then the measure μ is determined by the real-valued function f(x) = μ(Px) on the unit sphere, a function which has the property that [see pdf for formula] for each orthonormal basis E. Gleason calls such a function f a frame function of weight W. If T is a positive operator of trace class, then f(x) = ‹Tx,x› is a frame function. Gleason's theorem is that every frame function arises in this way. The original reference for Gleason's theorem is [4], which can also be found in Hooker [6]. Cooke, Keane and Moran [3] gave a proof that is elementary in the sense that it does not appeal to the theory of representations of the orthogonal group, which the original proof does. However, some of the reasoning in [3] seems hopelessly nonconstructive, so we follow the general outline of [4] until we come to the end of the 3-dimensional real case, at which point we modify some arguments in [3] rather than attempt a constructive development of the necessary representation theory. Any Hermitian form B on a finite-dimensional inner product space gives rise to a frame function f(x) = B(x; x) whose weight is equal to the trace of the matrix of B. The essence of Gleason's theorem is the following converse. -- from Introduction

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  • Imprecise Reasoning about Geographic Information

    Guesgen, H.W (1997-09)

    Report
    The University of Auckland Library

    This report summarizes preliminary work on a framework for imprecise reasoning about spatial information, in particular spatial information in geographic information systems. It is based on papers previously published by Jonathan Histed, Ute Lörch, David Poon, and the author. Geographic information systems have gained an increasing interest over the recent years. However, their abilities are restricted in that they usually reason about precise quantitative information only, which means that they fail whenever exact matches cannot be found. They do not allow for any form of reasoning with imprecision. In this report, we describe a way of incorporating imprecise qualitative spatial reasoning with quantitative reasoning in geographic information systems. In particular, we show how tessellation data models can be extended to allow for qualitative spatial reasoning. The idea is to associate qualitative information with fuzzy sets whose membership grades are computed by applying the concept of proximity. In addition, we will show how images like geographic maps or satellite images can be analyzed by computing the distances between given reference colors and the colors that occur in the image, and how the results of this analysis can be used in the fuzzy spatial reasoner.

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  • Cooperating Distributed Splicing Systems

    Martin-Vide, C; Paun, G (1997-12)

    Report
    The University of Auckland Library

    We introduce a new class of cooperating distributed H systems which consist of a given set of splicing systems (sets of splicing rules plus sets of axioms), similar in form to the cooperating distributed grammar systems. By applying iteratively the components of such a system (starting from a given initial string), in a sequence which runs nondeterministically, in such a way that a step is considered correctly finished only if no more splicing is possible, we obtain a language. Somewhat surprisingly if we take into account the loose control on the operations we carry out, a characterization of recursively enumerable languages is obtained, by mechanisms as above with only three components. We also characterize the recursively enumerable languages by cooperating distributed H systems with the components containing at most three splicing rules (in this case the number of components is no longer bounded).

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  • The Effective Riemann Mapping Theorem

    Hertling, P (1997-11)

    Report
    The University of Auckland Library

    The main results of the paper are two effective versions of the Riemann mapping theorem. The first, uniform version is based on the constructive proof of the Riemann mapping theorem by Bishop and Bridges and formulated in the computability framework developed by Kreitz and Weihrauch. It states which topological information precisely one needs about a nonempty, proper, open, connected, and simply connected subset of the complex plane in order to compute a description of a holomorphic bijection from this set onto the unit disk, and vice versa, which topological information about the set can be obtained from a description of a holomorphic bijection. The second version, which is derived from the first by considering the sets and the functions with computable descriptions, characterizes the subsets of the complex plane for which there exists a computable holomorphic bijection onto the unit disk. This solves a problem posed by Pour-El and Richards. We also show that this class of sets is strictly larger than a class of sets considered by Zhou, which solves an open problem posed by him. In preparation, recursively enumerable open subsets and closed subsets of Euclidean spaces are considered and several effective results in complex analysis are proved.

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  • A Low-Cost Decoder for Arbitrary Binary Variable-Length Codes

    Gunther, Ulrich; Nicolescu, Radu (1997-10)

    Report
    The University of Auckland Library

    Encoders and decoders for variable-length codes such as Huffman Codes can be costly to implement. This paper describes low-cost encoder and decoder for binary variable-length codes that is simple to implement when decoding speed is not an issue.

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  • Construction of Time-Relaxed Minimal Broadcast Networks

    Dinneen, Michael; Ventura, Jose; Wilson, Mark; Zakeri, Golbon (1997-02)

    Report
    The University of Auckland Library

    In broadcasting, or one-to-all communication, a message originally held in one node of the network must be transmitted to all the other nodes. A minimal broadcast network is a communication network that can transmit a message originated at any node to all other nodes of the network in minimum time. In this paper, we present a compound method to construct sparse, time-relaxed, minimal broadcast networks (t-mbn), in which broadcasting can be accomplished in slightly more than the minimum time. The proposed method generates a new network by connecting a subset of nodes from several copies of a t₁-mbn using the structure of another t₂-mbn. The objective is to construct a network as sparse as possible satisfying the desired broadcasting time constraint. Computational results illustrate the effectiveness of the proposed method.

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  • A Fast, Constant-Order, Symbol Ranking Text Compressor

    Fenwick, P. (1997-04)

    Report
    The University of Auckland Library

    Recent work on “symbol ranking” text compressors included a version which combines moderate compression with high speed and has been described in a poster at the 1997 Data Compression Conference. That work is extended here, especially to produce a compressor capable of efficient hardware implementation. The compressor is based on a conventional set-associative cache, with LRU update. To process a symbol, a context of the three preceding symbols is hashed to access a particular cache line. If the access “hits”, the LRU index is emitted as the recoded symbol, or otherwise the symbol is emitted and the LRU status updated. Several versions are described, with some improving the performance by maintaining a Move-To-Front list of symbols and emitting some symbols as “short” 5-bit indices into this table, or by encoding runs of correctly-predicted symbols. The final performance is in the range of 3.5 – 4 bits per byte over the Calgary Corpus, with software speeds of up to 1 Mbyte/s. The best of the hardware designs should run at 100Mbyte/s with discrete components, or 200–300 Mbyte/s with a completely integrated design.

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  • Polygonization of Quasi-Convolutionally Smoothed Polyhedra

    Wuensche, Burkhard; Lobb, R.J. (1997-04)

    Report
    The University of Auckland Library

    The smoothing of a polyhedral model is an important task in Computer Graphics. Richard Lobb [Lobb96] introduced quasi-convolutional smoothing, a fast rounding scheme approximating convolutional smoothing. For a fast interactive display of the model its surface must be polygonized. We introduce here Triage Polygonization, a new fast polygonization method for quasi-convolutionally smoothed polyhedral. The polygonization method exploits the property that quasi-convolutionally smoothed polyhedral usually have predominantly planar surfaces with only edges and corners rounded. A quasi-convolutionally smoothed polyhedron is represented implicitly as a density field isosurface. Triage Polygonization subdivides the density field in a BSP-like manner and classifies the resulting cells as inside, outside, or intersected by the isosurface. Planar surface areas usually lie on the boundary of cells and are extracted directly from the subdivided density field with minimal fragmentation. For cells intersected by the isosurface a more general polygonization is rounding radius Triage Polygonization is 20-30 times faster and outputs only 1-2% of the polygons of the marching Cubes algorithm without compromising the approximation. The approach taken for Triage Polygonization can be extended to related problems.

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  • Dimension Functions for T0 Digital Spaces (CST)

    Wiederhold, Petra; Wilson, Richard (1997-05)

    Report
    The University of Auckland Library

    Alexandro T0-spaces have been studied as topological models of the supports of digital images and as discrete models of continuous spaces in theoretical physics. In this paper we discuss three di erent dimension functions for this class of spaces, namely the Alexandro dimension, the Order dimension and the Krull dimension and we outline a proof of the equality of these dimension functions in this class. The rst of these is essentially the small inductive dimension well-known in topology, the second has been studied in the theory of posets while the third has been studied extensively as a dimension function for lattices and rings and was rst applied to topological spaces by Vinokurov in 1966. Since the category of Alexandro T0-spaces is known to be isomorphic to the category of posets, these results could be formulated in this latter category as well.

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