bluuebunny/crossref_metadata_2025 huggingface dataset:
A Web-Based Knowledge Elicitation System (GISEL) for Planning and Assessing Group Screening Experiments for Product Development
Authors: Dupplaw David P. , Brunson David , Vine Anna-Jane E. , Please Colin P. , Lewis Susan M. , Dean Angela M. , Keane Andy J. , Tindall Marcus J.
Published: September 2004

When planning experiments to examine how product performance depends on the design, manufacture and environment of use, there are invariably too few resources to enable a complete investigation of all possible variables (factors). We have developed new algorithms for generating and assessing efficient two-stage group screening strategies which are implemented through a web-based system called GISEL. This system elicits company knowledge which is used to guide the formulation of competing two-stage strategies and, via the algorithms, to provide quantitative assessment of their efficiencies. The two-stage group screening method investigates the effect of a large number of factors by grouping them in a first stage experiment whose results identify factors to be further investigated in a second stage. Central to the success of the procedure is ensuring that the factors considered, and their grouping, are based on the best available knowledge of the product. The web-based software system allows information and ideas to be contributed by engineers at different sites and allows the experiment organizer to use these expert opinions to guide decisions on the planning of group screening experiments. The new group screening algorithms implemented within the software give probability distributions and indications of the total resource needed for the experiment. In addition, the algorithms simulate results from the experiment and estimate the percentage of important or active main effects and interactions that fail to be detected. The approach is illustrated through the planning of an experiment on engine cold start optimization at Jaguar Cars.
Measurement and Modeling of Propeller Cavitation in Uniform Inflow
Authors: Pereira Francisco , Salvatore Francesco , Di Felice Fabio
Published: September 2004

An experimental and theoretical investigation on a cavitating propeller in uniform inflow is presented. Flow field investigations by advanced imaging techniques are used to extract quantitative information on the cavity extension. A refined map of the propeller cavitating behavior is established. Measurements are compared to numerical results obtained using an inviscid flow boundary element method for the analysis of blade partial sheet cavitation and supercavitation. The effect of the trailing wake vorticity on the prediction of the cavitation pattern is analyzed via a wake alignment technique.
Propagation of sound through a spicy ocean, the SOFAR overture
Authors: Dzieciuch Matthew , Munk Walter , Rudnick Daniel L.
Published: September 2004

Using a closely sampled 1000-km hydrographic section in the eastern North Pacific, the sound-speed finestructure is separated into two component fields: (i) isopyncal tilt dominated by internal waves (the traditional view) and (ii) “spicy” (cold-fresh to hot-salty) millifronts associated with upper ocean stirring. Numerical transmission experiments show significant scatter within the mixed layer from the spicy fronts. This scattered energy arrives near the start of the SOFAR sequence, and is superimposed on a triplication of the channel dispersion at the transition from reflected to upper ocean refracted energy. (This SOFAR overture is totally different from the finale which has been prominent for over 50 years.) The critical dependence of the overture on mixed layer processes suggests a scheme for acoustically monitoring the upper oceans at surface-conjugate depths (3 to 5 km), offering some advantages over in situ monitoring.
Synthesis of 1-Glycosyl Derivatives of Benzocamalexin
Authors: Humeník Martin , Dzurilla Milan , Kutschy Peter , Solčániová Eva , Kováčik Vladimír , Bekešová Slávka
Published: September 2004

The linear synthesis of 1-(β-D-glucopyranosyl)-, 1-(β-D-galactopyranosyl)-, 1-(β-D-mannopyranosyl)- and 1-(β-D-ribofuranosyl)benzocamalexin was elaborated from indoline as a starting compound and corresponding pentaacetylhexoses or 1-O-acetyl-2,3,5-tri-O-benzoyl-D-ribose as suitable glycosyl donors.
STEINER POINTS IN THE SPACE OF GENOME REARRANGEMENTS
Authors: SANKOFF DAVID , SUNDARAM GOPALAKRISHNAN , KECECIOGLU JOHN
Published: September 2004

We present some experiences with the problem of multiple genome comparison, analogous to multiple sequence alignment in sequence comparison, under the inversion and transposition distance metrics, given a fixed phylogeny. We first describe a heuristic for the case in which phylogeny is a star on three vertices and then use this to approximate the multiple genome comparison problem via local search.
SIMPLE ALGORITHMS FOR PERFECT PHYLOGENY AND TRIANGULATING COLORED GRAPHS
Authors: AGARWALA RICHA , FERNÁNDEZ-BACA DAVID
Published: September 2004

This paper presents an O((r–n/m)mrnm) algorithm for determining whether a set of n species has a perfect phylogeny, where m is the number of characters used to describe a species and r is the maximum number of states that a character can be in. The perfect phylogeny algorithm leads to an O((2e/k)ke2k) algorithm for triangulating a k-colored graph having e edges.
ALIGNMENT-TO-ALIGNMENT EDITING WITH “MOVE GAP” OPERATIONS
Authors: FÜRER MARTIN , MILLER WEBB
Published: September 2004

An alignment of k given sequences is a k-rowed matrix frequently used by molecular biologists to display correspondences between entries from each sequence. Under one approach, an alignment is represented by a matrix of ‘x’ and ’-’ characters, where each x in row r indicates the position of an entry of sequence r. It is sometimes efficient to store only the run-length encoding of each row of this bit-matrix. A natural class of commands for editing one such row into another consists of operations of the form: “Move the d dashes that begin at position i of row r to position j of that row,” for relevant values of r, d, i and j. We show that the problem of determining a shortest sequence of such operations that converts one given alignment to another is NP-hard and give a polynomial-time algorithm that always comes within a factor 5/4 of optimality. An application of these ideas to alignments of long DNA sequences is discussed.
ON THE EDITING DISTANCE BETWEEN UNDIRECTED ACYCLIC GRAPHS
Authors: ZHANG KAIZHONG , WANG JASON T.L. , SHASHA DENNIS
Published: September 2004

We consider the problem of comparing CUAL graphs (Connected, Undirected, Acyclic graphs with nodes being Labeled). This problem is motivated by the study of information retrieval for bio-chemical and molecular databases. Suppose we define the distance between two CUAL graphs G1 and G2 to be the weighted number of edit operations (insert node, delete node and relabel node) to transform G1 to G2. By reduction from exact cover by 3-sets, one can show that finding the distance between two CUAL graphs is NP-complete. In view of the hardness of the problem, we propose a constrained distance metric, called the degree-2 distance, by requiring that any node to be inserted (deleted) have no more than 2 neighbors. With this metric, we present an efficient algorithm to solve the problem. The algorithm runs in time O(N1N2D2) for general weighting edit operations and in time [Formula: see text] for integral weighting edit operations, where Ni, i=1, 2, is the number of nodes in Gi, D=min{d1, d2} and di is the maximum degree of Gi.
ON FINDING TOPOLOGICALLY VALID MATCHINGS IN RESTRICTION-FRAGMENT MAPS
Authors: HANKS LIZ , CYTRON RON K. , GILLETT WILL
Published: September 2004

We examine a problem that arises in physical DNA mapping, namely determining what common DNA is represented in two maps. We present an example illustrating the properties of DNA mapping, and motivate our approach. We present a new graph structure, called the Ƶ-graph, that takes advantage of structure that develops during the mapping process, thus catalyzing the discovery of all relevant fragment matchings. We describe an algorithm based on this structure and present experimental data supporting its improved performance as compared with a naive approach.
COVERING A CIRCULAR STRING WITH SUBSTRINGS OF FIXED LENGTH
Authors: DUVAL ART M. , SMYTH W.F.
Published: September 2004

A nonempty circular string C(x) of length n is said to be covered by a set Uk of strings each of fixed length k≤n iff every position in C(x) lies within an occurrence of some string u∈Uk. In this paper we consider the problem of determining the minimum cardinality of a set Uk which guarantees that every circular string C(x) of length n≥k can be covered. In particular, we show how, for any positive integer m, to choose the elements of Uk so that, for sufficiently large k, uk≈σk–m, where uk=|Uk| and σ is the size of the alphabet on which the strings are defined. The problem has application to DNA sequencing by hybridization using oligonucleotide probes.
LINEAR-TIME ALGORITHMS FOR DISJOINT TWO-FACE PATHS PROBLEMS IN PLANAR GRAPHS
Authors: RIPPHAUSEN-LIPA HEIKE , WAGNER DOROTHEA , WEIHE KARSTEN
Published: September 2004

In this paper we present a linear-time algorithm for the vertex-disjoint Two-Face Paths Problem in planar graphs, i.e., the problem of finding k vertex-disjoint paths between pairs of terminals which lie on two face boundaries. The algorithm is based on the idea of finding rightmost paths with a certain property in planar graphs. Using this method, a linear-time algorithm for finding vertex-disjoint paths of a prescribed homotopy is derived. Moreover, the algorithm is modified to solve the more general linkage problem in linear time, as well.
TREEWIDTH OF CIRCLE GRAPHS
Authors: KLOKS T.
Published: September 2004

In this paper we show that the treewidth of a circle graph can be computed in polynomial time. A circle graph is a graph that is isomorphic to the intersection graph of a finite collection of chords of a circle. The TREEWIDTH problem can be viewed upon as the problem of finding a chordal embedding of the graph that minimizes the clique number. Our algorithm to determine the treewidth of a circle graph can be implemented to run in O(n3) time, where n is the number of vertices of the graph.
CONSTRUCTING DEGREE-3 SPANNERS WITH OTHER SPARSENESS PROPERTIES
Authors: DAS GAUTAM , HEFFERNAN PAUL J.
Published: September 2004

Let V be any set of n points in k-dimensional Euclidean space. A subgraph of the complete Euclidean graph is a t-spanner if for all u and υ in V, the length of the shortest path from u to υ in the spanner is at most t times the Euclidean distance between u and υ. We show that for any δ>1, there exists a t-spanner (where t is a constant that depends only on δ and k) with the following properties: its maximum degree is 3, it has at most n·δ edges, its total edge weight is at most O(1) times the weight of the minimum spanning tree of V, and it can be constructed in O(n log n) time. The constants implicit in the O-notation depend on δ and k.
A SIMPLE BALANCED SEARCH TREE WITH O(1) WORST-CASE UPDATE TIME
Authors: FLEISCHER RUDOLF
Published: September 2004

In this paper we show how a slight modification of (a, 2b)-trees allows us to perform member and neighbor queries in O( log n) time and updates in O(1) worst-case time (once the position of the inserted or deleted key is known). Our data structure is quite natural and much simpler than previous worst-case optimal solutions. It is based on two techniques : 1) bucketing, i.e., storing an ordered list of 2 log n keys in each leaf of an (a, 2b) tree, and 2) preventive splitting, i.e., splitting nodes before they can grow bigger than allowed. If only insertions are allowed, it can also be used as a finger search tree with O( log * n) worst-case update time.
AN EFFECTIVE CAUCHY-PEANO EXISTENCE THEOREM FOR UNIQUE SOLUTIONS
Authors: RUOHONEN KEIJO
Published: September 2004

It is shown in this paper that the solution of the initial value problem for a system of ordinary differential equations is computable if the following assumptions are satisfied: The time interval considered is computable, the system is continuous and computable, the initial values are computable, the system is effectively bounded, and the solution is unique. It should be mentioned that for a single ODE this follows immediately from the standard proof of Osgood’s existence theorem, but this approach is not available for systems of ODEs. The key assumption here is uniqueness of solution: a result of Pour-El’s and Richards’ shows that nonunique solutions may be noncomputable, even for a single ODE.
SUBTREE ISOMORPHISM IS IN DLOG FOR NESTED TREES
Authors: GREENLAW RAYMOND
Published: September 2004

This research shows subtree isomorphism is in DLOG, and hence [Formula: see text], for nested trees. To our knowledge this result provides the first interesting class of trees for which the problem is in a non-randomized version of [Formula: see text]. We also show that one can determine whether or not an arbitrary tree is a nested tree in DLOG.
EFFICIENT REBALANCING OF B-TREES WITH RELAXED BALANCE
Authors: LARSEN KIM S. , FAGERBERG ROLF
Published: September 2004

B-trees with relaxed balance have been defined to facilitate fast updating on shared-memory asynchronous parallel architectures. To obtain this, rebalancing has been uncoupled from the updating so that extensive locking can be avoided in connection with updates.

We analyze B-trees with relaxed balance, and prove that each update gives rise to at most [loga(N/2)]+1 rebalancing operations, where a is the degree of the B-tree, and N is the bound on its maximal size since it was last in balance. Assuming that the size of nodes is at least twice the degree, we prove that rebalancing can be performed in amortized constant time. So, in the long run, rebalancing is constant time on average, even if any particular update could give rise to a logarithmic number of rebalancing operations. We also prove that the amount of rebalancing done at any particular level decreases exponentially going from the leaves towards the root. This is important since the higher up in the tree a lock due to a rebalancing operation occurs, the larger a subtree which cannot be accessed by other processes for the duration of that lock. All of these results are in fact obtained for the more general (a, b)-trees, so we have results for both of the common B-tree versions as well as 2-3 trees and 2-3-4 trees.
INDUCTIVE INFERENCE OF LIMITING PROGRAMS WITH BOUNDED NUMBER OF MIND CHANGES
Authors: VĪKSNA JURIS
Published: September 2004

We consider inductive inference of total recursive functions in the case, when produced hypotheses are allowed some finite number of times to change “their mind” about each value of identifiable function. Such type of identification, which we call inductive inference of limiting programs with bounded number of mind changes, by its power lies somewhere between the traditional criteria of inductive inference and recently introduced inference of limiting programs.

We consider such model of inductive inference for EX and BC types of identification, and we study

• tradeoffs between the number of allowed mind changes and the number of anomalies, and

• relations between classes of functions identifiable with different probabilities.

For the case of probabilistic identification we establish probabilistic hierarchies which are quite unusual for EX and BC types of inference.
STORAGE OVERHEAD OF O-TREES, B-TREES AND PREFIX B-TREES: A COMPARATIVE ANALYSIS
Authors: ORLANDIC RATKO , MAHMOUD HOSAM M.
Published: September 2004

The O-tree is an indexing mechanism closely related to B-trees and Prefix B-trees. In this paper we derive the expected storage overhead of O-Trees under the standard Bernoulli model of randomness, compare the results with the expected overhead of B-trees and Prefix B-trees under the same conditions, and assess the expected relative improvements.
OPTIMAL OPERATIONS ON RED-BLACK TREES
Authors: CHEN LIN , SCHOTT RENÉ
Published: September 2004

We show here that on a red-black tree with only two pointers — left pointing to the left child and right pointing to the right child — for each node, some standard operations such as searching, deletion, and insertion can be performed in O( log n) time, in the worst case, using only O(1) auxiliary space. No procedures do these fundamental operations more efficiently in time and space. The time and the space bounds of our algorithms are both optimal. The result is achieved by applying the pointer altering technique on red-black trees. The usefulness of the technique is further illustrated in this paper. Efficient implementations of the algorithms are also addressed here.
SAFE TURING MACHINES, GRZEGORCZYK CLASSES AND POLYTIME
Authors: CAPORASO SALVATORE
Published: September 2004

We introduce a class of safe Turing machines which execute structured while, if-then- else programs and operate on stacks and on a read-only input tape. A hierarchy is obtained by taking as Si the class of all functions computed by programs of loop-depth i. The main result is that S1 equals Lintime and S2 equals Polytime while, for i≥3, we have that Si equals the i-th Grzegorczyk class. By adding to the language a non-deterministic construct choose we take S2 into a class equivalent to NP. This gives a syntactical characterization in a pure-machine model of the mentioned classes.
MULTI-PUSH-DOWN LANGUAGES AND GRAMMARS
Authors: BREVEGLIERI LUCA , CHERUBINI ALESSANDRA , CITRINI CLAUDIO , REGHIZZI STEFANO CRESPI
Published: September 2004

A new class of languages, called multi-push-down (mpd), that generalize the classical context-free (cf, or Chomsky type 2) ones is introduced. These languages preserve some important properties of cf languages: a generalization of the Chomsky-Schützenberger homomorphic characterization theorem, the Parikh theorem and a “pumping lemma” are proved. Multi-push-down languages are an AFL. Their recognizers are automata equipped with a multi-push-down tape. Multi-push-down languages form a hierarchy based on the number of push-down tapes.
DEPTH AND PATH LENGTH OF HEAP ORDERED TREES
Authors: PRODINGER HELMUT
Published: September 2004

A heap ordered tree of size n is a planted plane tree together with a bijection from the nodes to the set {1,…,n} which is monotonically increasing when going from the root to the leaves. In a recent paper by Chen and Ni, the expectation and the variance of the depth of a random node in a random heap ordered tree of size n was considered. Here, we give additional results concerning level polynomials. From a historical point of view, we trace these trees back to an earlier paper by Prodinger and Urbanek and find formulae that are proved in the paper by Chen and Ni by ad hoc computations already in a classic book by Greene and Knuth. Also, we mention that a paper by Bergeron, Flajolet and Salvy develops a more general theory of increasing trees, based on simply generated families of trees. Furthermore we consider the path length which is a natural concept when dealing with the depth. Expectation and variance are obtained, both explicitly and asymptotically.
AN ALGORITHM FOR FINDING A MAXIMUM CYCLE OF BIPARTITE GRAPHS WITH LARGE DEGREES
Authors: WONG PAK-KEN
Published: September 2004

Let G be a simple bipartite graph with bipartition (X, Y) such that |X|≥|Y|≥2. Put n=|X|, m=|Y| and p=m+n. Suppose, for each pair of nonadjacent vertices x∈X and y∈Y we have d(x)+d(y)≥n+1. We give an efficient algorithm to obtain a cycle of length 2m in G. The complexity of this algorithm is O(p2). In particular, if m=n, we have a hamiltonian cycle of G.
FAMILIES OF NONCOUNTING LANGUAGES AND THEIR LEARNABILITY FROM POSITIVE DATA
Authors: KOBAYASHI SATOSHI , YOKOMORI TAKASHI
Published: September 2004

This paper introduces some subclasses of noncounting languages and presents some results on the learnability of the classes from positive data. We first establish several relationships among the language classes introduced and the class of reversible languages. Especially, we introduce the notion of local parsability, and define a class (k, l)-CLTS, which is a subclass of the class of concatenations of strictly locally testable languages. We show its close relation to the class of reversible languages.

We then study on the relationship between the closure of the Boolean operations and the learnability in the limit from positive data only. Further, we explore the learnability question of some subclasses of noncounting languages in the model of identification in the limit from positive data. In particular, we show that, for each k, l≥1, (k, l)-CLTS is identifiable in the limit from positive data using reversible automata with the conjectures updated in polynomial time. Some possible applications of the result are also briefly discussed.
A NOTE ON MULTIHEAD FINITE-STATE AUTOMATA
Authors: MACARIE IOAN I.
Published: September 2004

We present connections among nondeterministic and one-sided-error probabilistic multihead finite-state automata. Several properties of logarithmic-space Turing machines follow from the more refined results that we prove in the setting of the corresponding multihead finite-state automata.
ON THE ISOMORPHISM CONJECTURE FOR 2-DFA REDUCTIONS
Authors: AGRAWAL MANINDRA , VENKATESH S.
Published: September 2004

The degree structure of complete sets under 2DFA reductions is investigated. It is shown that, for any class [Formula: see text] that is closed under log-lin reductions:

• All complete sets for the class [Formula: see text] under 2DFA reductions are also complete under one-one, length-increasing 2DFA reductions and are first-order isomorphic.

• The 2DFA-isomorphism conjecture is false, i.e., the complete sets under 2DFA reductions are not isomorphic to each other via 2DFA reductions.
SCHEDULING TWO SALESMEN IN A NETWORK
Authors: KLOSTERMEYER WILLIAM F.
Published: September 2004

The two-server problem is concerned with the movement of two servers to request points in a metric space. We consider an offline version of the problem in a graph in which the requests may be served in any order. A family of approximations algorithms is developed for this NP-complete problem.
ON THE PROPOSITIONAL SLDNF-RESOLUTION
Authors: PLAZA JAN A.
Published: September 2004

We consider propositional logic programs with negations. We define notions of constructive transformation and constructive completion of a program. We use these notions to characterize SLDNF-resolution in classical, intuitionistic and intermediate logics, and also to derive a characterization in modal logics of knowledge. We show that the three-valued and four-valued fix-point or declarative semantics for program P are equivalent to the two-valued semantics for the constructive version of P.

We argue that it would be beneficial to replace Negation as Failure by constructive transformation, and it would be beneficial to use the semantics for the constructive version of the program instead of multivalued semantics for the original program.
THE LANE EXPANSION EFFECT OF THE TOLLBOOTH SYSTEM ON THE HIGHWAY
Authors: JIANG RUI , JIA BIN , WU QING-SONG
Published: September 2004

In this paper, we investigate the lane expansion effect of the tollbooth system. To this end, two typical values of randomization probability p:p=0.5 and p=0.1 are chosen. It is shown that for p=0.5, the full capacity of the single lane highway can be restored. However, for p=0.1, our simulations show that the full capacity of the single lane highway cannot be restored due to the existence of the merge section in the lane expansion section. Moreover, we have investigated the dependence of road capacity on the length of lane expansion section as well as the effects of the positions of the tollbooths in the lane expansion section under different values of p.
THE EFFECT OF THE RANGE OF THE POTENTIAL ON THE MULTI-STEP CLUSTER MELTING PROCESS
Authors: REN SHI-WEI
Published: September 2004

By using the microcanonical molecular dynamics simulation, the melting processes of the clusters bound by Morse potential are investigated. It is found that these clusters show a multi-step melting process as long as the range of the Morse potential is a suitable value. The origins of this multi-step process are analyzed. I find that not only the repulsive core of the potential but also the attractive tail range of the potential influences the melting process. Moreover, the occurrence of the multi-step melting process is more sensitive to the tail region of the Morse potential.
GENERALIZED SYNCHRONIZATION AND MEMORY EFFECT IN THE BURRIDGE–KNOPOFF SYSTEM OF THREE BLOCKS
Authors: SZKUTNIK JACEK , KUŁAKOWSKI KRZYSZTOF
Published: September 2004

Recently, synchronization in the Burridge–Knopoff model has been found to depend on the initial conditions. Here we report the existence of three modes of oscillations of the system of three blocks. In one of the modes, two lateral blocks are synchronized. In the second mode, the central block moves with almost constant velocity, i.e., it does not stick. Two lateral blocks do stick and they move in opposite phases. In the third mode, the blocks oscillate with aperiodic amplitude. The lateral blocks move in opposite phases and their frequency is lower than the one for the central block. The mode selected by the system depends on the initial conditions. Numerical results indicate that there is no modes in the phase space.
EXPLANATION OF THE REACTION OF MONOCLONAL ANTIBODIES WITH CANDIDA ALBICANS CELL SURFACE IN TERMS OF COMPOUND POISSON PROCESS
Authors: DUDEK MIROSŁAW R. , MLECZKO JÓZEF
Published: September 2004

Surprisingly, still very little is known about the mathematical modeling of peaks in the binding affinities distribution function. In general, it is believed that the peaks represent antibodies directed towards single epitopes. In this paper, we refer to fluorescence flow cytometry experiments and show that even monoclonal antibodies can display multi-modal histograms of affinity distribution. This result take place when some obstacles appear in the paratope–epitope reaction such that the process of reaching the specific epitope ceases to be a point Poisson process. A typical example is the large area of cell surface, which could be unreachable by antibodies leading to the heterogeneity of the cell surface repletion. In this case the affinity of cells to bind the antibodies should be described by a more complex process than the pure-Poisson point process. We suggested to use a doubly stochastic Poisson process, where the points are replaced by a binomial point process resulting in the Neyman distribution. The distribution can have a strongly multinomial character, and with the number of modes depending on the concentration of antibodies and epitopes. All this means that there is a possibility to go beyond the simplified theory, one response towards one epitope. As a consequence, our description provides perspectives for describing antigen–antibody reactions, both qualitatively and quantitavely, even in the case when some peaks result from more than one binding mechanism.
THE INFLUENCE OF CONTRARIANS AND OPPORTUNISTS ON THE STABILITY OF A DEMOCRACY IN THE SZNAJD MODEL
Authors: SCHNEIDER JOHANNES J.
Published: September 2004

Sznajd-Weron and Sznajd introduced a model investigating the democratic development in a closed community. This model is based on the USDF-principle ("united we stand, divided we fall"). However, it faces the problem that the system tends either to a dictatorship (i.e., 100% pro or 100% contra) or to a stalemate state (i.e., exactly 50% pro, 50% contra). Based on their model, I will show that a democratic system keeps alive due to the existence of both opportunists and persons in opposition.
THERMODYNAMIC CALCULATION OF n-COMPONENT EUTECTIC MIXTURES
Authors: BRUNET L. , CAILLARD J. , ANDRÉ P.
Published: September 2004

This paper presents a simple numerical method to calculate the eutectic mixture composition and melting temperature. Using a Newton–Raphson method to solve the nonlinear problem, the calculation is possible for n-component eutectic. We tested this algorithm on inorganic and organic mixtures. A better correlation between experimental and numerical results has been found for organic compound.
STUDY ON EFFECTS OF THE STOCHASTIC DELAY PROBABILITY FOR 1D CA MODEL OF TRAFFIC FLOW
Authors: XUE YU , CHEN YAN-HONG , KONG LING-JIANG
Published: September 2004

Considering the effects of different factors on the stochastic delay probability, the delay probability has been classified into three cases. The first case corresponding to the brake state has a large delay probability if the anticipant velocity is larger than the gap between the successive cars. The second one corresponding to the following-the-leader rule has intermediate delay probability if the anticipant velocity is equal to the gap. Finally, the third case is the acceleration, which has minimum delay probability. The fundamental diagram obtained by numerical simulation shows the different properties compared to that by the NaSch model, in which there exist two different regions, corresponding to the coexistence state, and jamming state respectively.
INTEGRABILITY OF A NONAUTONOMOUS COUPLED KdV SYSTEM
Authors: KARASU(KALKANLI) AYŞE , KILIÇ TUBA
Published: September 2004

The Painlevé property of coupled, nonautonomous Korteweg–de Vries (KdV) type of systems is studied. The conditions under which the systems pass the Painlevé test for integrability are obtained. For some of the integrable cases, exact solutions are given.
DISCRETE LATTICE BGK BOLTZMANN EQUATION COMPUTATIONS OF TRANSIENT INCOMPRESSIBLE TURBULENT JETS
Authors: PREMNATH KANNAN N. , ABRAHAM JOHN
Published: September 2004

In this paper, computations of transient, incompressible, turbulent, plane jets using the discrete lattice BGK Boltzmann equation are reported. Á priori derivation of the discrete lattice BGK Boltzmann equation with a spatially and temporally dependent relaxation time parameter, which is used to represent the averaged flow field, from its corresponding continuous form is given. The averaged behavior of the turbulence field is represented by the standard k–∊ turbulence model and computed using a finite-volume scheme on nonuniform grids. Computed results are compared with analytical solutions, experimental data and results of other computational methods. Satisfactory agreement is shown.
CONSTRUCTING FAMILIES OF EXACT SOLUTIONS TO A (2+1)-DIMENSIONAL CUBIC NONLINEAR SCHRÖDINGER EQUATION
Authors: LI BIAO , ZHANG HONGQING
Published: September 2004

The projective Riccati equations method is extended to find some novel exact solutions of a (2+1)-dimensional cubic nonlinear Schrödinger (NLS) equation. Applying the extended method and symbolic computation, six families of exact analytical solutions for this NLS equation are reported, which include some new and more general exact soliton-like solutions, trigonometric function forms solutions and rational forms solutions.
ON THE WANG–LANDAU METHOD USING THE N-FOLD WAY
Authors: MALAKIS A. , MARTINOS S. S. , HADJIAGAPIOU I. A. , PERATZAKIS A. S.
Published: September 2004

We present a variation of the N-fold way algorithm, which improves efficiency when one combines the Wang–Landau method with the N-fold way. It is shown that the new version of the N-fold way algorithm has good performance when used for importance sampling and compared with the usual N-fold version or the Metropolis algorithm. The new N-fold algorithm combined with the Wang–Landau method is applied to the square Ising model using a multi-range approach. A comparative study is presented for all these algorithms, Wang–Landau and the two combined versions with the N-fold way. The role of boundary effects is discussed.
FORCED MUON CATALYZED FUSION IN HETEROGENEOUS LAYERS OF HYDROGEN ISOTOPES
Authors: ESKANDARI M. R. , GHEISARI R.
Published: September 2004

Muon cycling dynamics for muon catalyzed fusion in heterogeneous solid layers are considered through decay of complex molecule [Formula: see text]. The suggested fusion system consists of three layers which are alternatively repeated. The first layer is D/T (deuterium, tritium) which provides [Formula: see text] molecules. The second layer is T2 molecules which are used to slow down the muonic atoms and the third layer is D2 molecules. The design is in a way in which dtμ, muonic deuterium and tritium molecules, are produced in resonance. It is shown, by considering muonic dynamics theoretically in a suggested heterogeneous system and determining its cycling rate by using a more advanced calculational method, that for equal deuterium, tritium concentration (Cd=Ct=0.5) in D/T layer and ϕ'=ϕ0=ϕ=1 (relative density for each layer respectively and given in liquid hydrogen density LHD=4.25×1022 cm -3), the muon cycling rate is optimum for the suggested heterogeneous system and has 15% enhancement with respect to the conventional D/T system. It is also shown that for ϕ0<0.0003 the muon cycling rate in D2 is almost stopped, and for ϕ0≥1 muon cycling rate increases, but this is not recommended due to low and costly tritium availability.
MACHINE VISION 1992–1996, TECHNOLOGY PROGRAM IN FINLAND
Authors: SOINI ANTTI J.
Published: September 2004

Machine vision technology has attracted a strong interest among Finnish research organizations, which has resulted in many innovative products for industry. Despite this goal users were very skeptical towards machine vision and its robustness in harsh industrial environments. Therefore the Technology Development Centre, TEKES, which funds technology related research and development projects in universities and individual companies in Finland, decided to start a national technology program, "Machine Vision 1992–1996".

Led by industry, the program boosts research in machine vision technology and seeks to put the research results to work in practical industrial applications. The emphasis is on nationally important, demanding applications. The program will create new business for machine vision producers and encourage the process and manufacturing industry to take advantage of this new technology. So far 60 companies and all major universities and research centers in Finland are working on our forty different projects. The key themes are Process Control, Robot Vision and Quality Control.
DESIGN OF IMAGE ACQUISITION FOR SURFACE INSPECTION
Authors: HÄRKÖNEN ARI , MIETTINEN JARI , MORING ILKKA
Published: September 2004

Since the design of an inspection system typically requires a lot of application-dependent work, the provision of systematic methods and tools to assist in the design process could significantly reduce the system development and installation time. With this in view, a step-by-step design procedure for image acquisition systems is suggested, consisting of measurements of certain important optical parameters for the surfaces to be inspected, modelling of the measurements and arrangement of the imaging in a form that a computer can understand, simulation of the imaging process in a computer using optical analysis tools, and verification of the results through a pilot system. The procedure is exemplified by describing its application to the design of a steel sheet inspection system and its capacity for optimising the detection of various defects is demonstrated. For comparison, measurements made on some other materials are shown and the implications discussed. The results of the simulation and the pilot system for steel are compared and the usefulness of the computer-based design method is evaluated.
AN INTELLIGENT CAMERA FOR ACTIVE VISION
Authors: PAU L.-F.
Published: September 2004

Much research is currently going on about the processing of one or two-camera imagery, possibly combined with other sensors and actuators, in view of achieving attentive vision, i.e. processing selectively some parts of a scene possibly with another resolution. Attentive vision in turn is an element of active vision where the outcome of the image processing triggers changes in the image acquisition geometry and/or of the environment. Almost all this research is assuming classical imaging, scanning and conversion geometries, such as raster based scanning and processing of several digitized outputs on separate image processing units.

A consortium of industrial companies comprising Digital Equipment Europe, Thomson CSF, and a few others, have taken a more radical view of this. To meet active vision requirements in industry, an intelligent camera is being designed and built, comprised of three basic elements:

– a unique Thomson CSF CCD sensor architecture with random addressing

– the DEC Alpha 21064 275MHz processor chip, sharing the same internal data bus as the digital sensor output

– a generic library of basic image manipulation, control and image processing functions, executed right in the sensor-internal bus-processor unit, so that only higher level results or commands get exchanged with the processing environment.

Extensions to color imaging (with lower spatial resolution), and to stereo imaging, are relatively straightforward. The basic sensor is 1024*1024 pixels with 2*10 bits addresses, and a 2.5 ms (400 frames/second) image data rate compatible with the Alpha bus and 64 bits addressing. For attentive vision, several connex fields of max 40 000 pixels, min 5*3 pixels, can be read and addressed within each 2.5 ms image frame. There is nondestructive readout, and the image processing addressing over 64 bits shall allow for 8 full pixel readouts in one single word.

The main difficulties have been identified as the access and reading delays, the signal levels, and dimensioning of some buffer arrays in the processor.

The commercial applications targeted initially will be in industrial inspection, traffic control and document imaging. In all of these fields, selective position dependent processing shall take place, followed by feature dependent processing.

Very large savings are expected both in terms of solutions costs to the end users, development time, as well as major performance gains for the ultimate processes. The reader will appreciate that at this stage no further implementation details can be given.
IMAGING SPECTROGRAPH AND CAMERA SOLUTIONS FOR INDUSTRIAL APPLICATIONS
Authors: HERRALA ESKO , OKKONEN JUKKA
Published: September 2004

An imaging spectrometer instrument based on a prism-grating-prism (PGP) element as the dispersive component and advanced camera solutions for on-line applications are presented. The PGP element uses a volume type holographic plane transmission grating made of dichromated gelatin (DCG). Currently, spectrographs have been realized for the 400–1050 nm region but applicable spectral region of the PGP is 380–1800 nm. Spectral resolution is typically between 1.5 and 5 nm. The on-axis optical configuration and simple rugged tubular optomechanical construction of the spectrograph provides a good image quality and resistance to harsh environmental conditions. Spectrograph optics are designed to be interfaced to any standard CCD camera. Special camera structures and operating modes can be used for applications requiring on-line data interpretation and process control.
SOME ASPECTS OF RGB VISION AND ITS APPLICATIONS IN INDUSTRY
Authors: MARSZALEC ELZBIETA , PIETIKÄINEN MATTI
Published: September 2004

RGB machine vision overlaps both colorimetry instrumentation and gray scale machine vision, and offers advantages over both. Proper calibration of the color camera which makes measurements independent of changes in illumination is essential for the reliability of color machine vision. A practical approach to on-line color camera calibration under unstable illumination conditions is presented and the performance of the procedure is evaluated. New potential applications of RGB machine vision are discussed from the perspective of physics-based vision and the calibration procedure developed here.
DETERMINING COMPOSITION OF GRAIN MIXTURES BY TEXTURE CLASSIFICATION BASED ON FEATURE DISTRIBUTIONS
Authors: OJALA TIMO , PIETIKÄINEN MATTI , NISULA JARKKO
Published: September 2004

Texture analysis has many areas of potential application in industry. The problem of determining composition of grain mixtures by texture analysis was recently studied by Kjell. He obtained promising results when using all nine Laws' 3 × 3 features simultaneously and an ordinary feature vector classifier. In this paper the performance of texture classification based on feature distributions in this problem is evaluated. The results obtained are compared to those obtained with a feature vector classifier. The use of distributions of gray level differences as texture measures is also considered.
RECENT DEVELOPMENTS IN WOOD INSPECTION
Authors: SILVÉN OLLI , KAUPPINEN HANNU
Published: September 2004

Automated grading of lumber is attractive for the sawmill industry. Achieving better accuracy of quality grading and control of quality variation in volume production easily improves the profit obtained from it.

We describe a color vision based framework to grading softwood lumber. The proposed inspection principle is to recognize the sound wood regions early, as this reduces the computational requirements at later defect recognition stages. The recognition stages are ordered based on their estimated costs and implementational complexity. This is important because color increases the data volumes significantly over grey scale images. Finally, the description of the board and its defects is passed to the quality grader which assigns the class giving the best price for each board.

In comparative tests, the computational solutions have turned out to be simpler than with grey level images, compensating for the higher cost of the color imaging system. The effects of changes in the spectrum of illumination have also been evaluated to identify robust color features and to produce the requirements for color calibration.
SELF-ORGANIZING FEATURE EXTRACTION IN RECOGNITION OF WOOD SURFACE DEFECTS AND COLOR IMAGES
Authors: LAMPINEN JOUKO , SMOLANDER SEPPO
Published: September 2004

A method for constructing classification features with unsupervised learning is presented. The method is based on clustering of the high dimensional measurements into a small number of features with self-organizing maps. The histograms of the self-organized features are classified with a multilayer perceptron network, that can pick up the relevant features and feature combinations from the histograms.

The method is applied in two industrial problems, color image recognition for selection of optimal reproduction parameters in the printing press, and defect classification in wood surfaces.

In both applications, the results were evaluated by the domain experts to be sufficient with respect to the application requirements. In the color image recognition the results were compared to the manually selected parameter settings, and in 12% of the test images there were distinquishable differences, with very few clear failures.

Performance of the wood defect classification system was evaluated with a set of 400 knot images with 7 classes from spruce boards. The recognition rate was about 85% with only gray level images, giving about 90% accuracy for the final board grading, to be compared to 75–80% accuracy that can be maintained by a human inspector.

As the methods are based on rather generic basic features and learning of the final features and classes from the samples, they are easily adaptable to different tasks, such as defect inspection in lumber or veneer, with different tree species or different cutting processes.
INSPECTION OF COLOUR PRINTING QUALITY
Authors: SÖDERGÅRD CAJ , LAUNONEN RAIMO , ÄIKÄS JUUSO
Published: September 2004

The use of machine vision technology is being investigated at VTT for improving the colour quality and productivity of web offset printing. The visual inspection of colour quality is performed by a colour CCD camera which traverses the moving web under a stroboscopic light. The measuring locations and goal values for the colour register, the ink density and the grey balance are automatically determined from the PostScript™ description of the digital page. A set of criteria is used to find the most suitable spots for the measurements. In addition to providing data for on-line control, the page analysis estimates the zone wise link consumption of the printing plates as a basis for presetting the ink feed. Target calorimetric CIE-values for grey balance and critical colours are determined from the image originals. The on-line measurement results and their derivations from the target values are displayed in an integrated manner. The paper gives test results of computation times, measurements of register error with and without test targets and the colour measuring capabilities of the system. The results show that machine vision can be used for on-line inspection of colour print quality. This makes it possible to upgrade older printing presses to produce a colour quality that is competitive with more modern presses.
IMAGE PROCESSING IN COMBUSTION CONTROL
Authors: HIRVONEN JUHANI , LILJA REIJO , IKONEN KARI , NIHTINEN JARMO
Published: September 2004

This paper describes an image processing system that calculates real time information from the combustion process itself. The applications of the system on burner and supplemental fuel adjustment, and ignition trend monitoring are also discussed. Finally, new combustion control based on the image information and quantitative model of the furnace is discussed.
ACCURATE 3-D MEASUREMENT USING A SINGLE VIDEO CAMERA
Authors: HEIKKILÄ JANNE , SILVÉN OLLI
Published: September 2004

We present a straightforward technique for determining the 3-D locations of feature points using sequences of monocular image frames captured by a moving camera. The motion of the camera is estimated simultaneously. In practice, only the camera needs careful calibration. Based on experiments, the repeatability is currently about 1/3500 and accuracy 1/2500. This approach has potential for high speed, as hundreds of points may be measured from the same image sequence.
3D MEASUREMENT CONTROLLED BY A CAD MODEL-BASED MEASUREMENT PLANNING AND VISION SYSTEM
Authors: AILISTO HEIKKI , MITIKKA RISTO , MORING ILKKA , JOKINEN HANNU , KAISTO ILKKA
Published: September 2004

Optical coordinate measurement systems will benefit from developments similar to those taking place in robots, namely off-line programming capability and intelligent sensors. Research work towards these goals is reported here. An experimental system with CAD model-based measurement planning and vision control has been constructed and its feasibility demonstrated. The system comprises a measurement planning tool, a measurement robot with vision guidance and a means of visualizing and comparing the measured results with the design data. The measurement planning tool is based on a commercial CAD system and enables the use of existing CAD models of the objects to be measured as a basis for planning. It generates a measurement model file (MMF) containing instructions for controlling the measurement robot, which is an optical coordinate measurement device based on the laser rangefinder principle and supplemented with a vision system for guiding the measurement to planned target points. The measured coordinate values can be compared with design values either graphically or numerically. The performance of the experimental system was demonstrated and evaluated. In the demonstration case a measurement sequence was planned and saved in the form of a MMF, whereupon the measurement robot was able to execute the sequence reliably according to the MMF and measure the planned target points with vision guidance. The pointing repeatability of the vision guidance function was 0.019 mRad (standard deviation), which is equal to 0.19 mm at a distance of 10 meters, and the corresponding pointing accuracy was better than 0.04 mRad. The 3D measurement had an average repeatability of 0.3 mm (standard deviation), and the absolute accuracy of averaged measurement results was better than ±1 mm (for x, y and z) in 81% of the cases. The next phase of the work will include piloting the system in an industrial application.