bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of ionic impurities on the primary nucleation of potassium sulphate solutions
Authors: Garside J. , Komarov V. F. 
Published: July 2007

AbstractA technique is described for rapidly assessing the effect of impurities on primary nucleation in solutions. The influence of Ca2+, Sr2+, Ba2+, Ag+, Pb2+, Cr3+ and Ni2+ on the nucleation of potassium sulphate solutions is discussed. It is generally observed that a discontinuity in the behaviour of the impurity occurs at an impurity concentration corresponding to the solubility of the “impurity sulphate” in the solution under investigation.
New model of the bond diffractometer for precise determination of lattice parameters and thermal expansion of single crystals
Authors: Łukaszewicz K. , Kucharczyk D. , Malinowski M. , Pietraszko A. 
Published: July 2007

AbstractA new model of diffractometer for very precise measurements (1 ppm accuracy) of lattice parameters and thermal expansion is presented. Special attention is paid to the temperature control and stability in a wide range from liquid nitrogen up to 800 K. Two examples of the application of the diffractometer in a study of solid state phase transitions are given.
Zur Errechnung der Intensitäten von Auger‐Übergängen für die quantitative Analyse von Festkörperoberflächen mit der Augerelektronenspektroskopie (AES)
Authors: Streubel P. , Apelt R. 
Published: July 2007

AbstractGemäß einer empirischen Gleichung für die Intensität von charakteristischen Augerelektronen, die durch Primärelektronenbeschuß aus einer Festkörperoberfläche austreten, wurden die einzelnen Parameter Ionisierungsquerschnitt, relative Wahrscheinlichkeit des Augerprozesses, Rückstreufaktor und mittlere Austrittstiefe der Augerelektronen für den L3M45M45‐Augerprozeß der Elemente mit den Ordnungszahlen Z = 22 bis 33 bestimmt. Ein Vergleich der berechneten relativen Intensitätswerte mit Meßwerten von Palmberg et al. zeigt die gute Übereinstimmung im allgemeinen Kurvenverlauf der ordnungszahlabhängigen Intensitäten. Die mittlere relative Abweichung der berechneten von den experimentellen Werten beträgt 20% und kommt damit den bisherigen Abschätzungen über die Genauigkeit der quantitativen AES ohne äußeren Standard nahe. Die Untersuchung des Einflusses der einzelnen Intensitätsparameter ergab, daß vor allem der Ionisierungsquerschnitt und im gegebenen Fall auch die relative Wahrscheinlichkeit des Augerprozesses den Intensitätswert bestimmen.
Thermodynamics of AlN deposition by means of the aluminium‐trichloride‐ammonia process
Authors: Arnold H. , Biste L. , Kaufmann Th. 
Published: July 2007

AbstractEquilibrium yields for CVD of AlN dependent on the input ratio AlCl3/NH3 and on temperature were computed(A) for AlCl3 + NH3 ⇋ AlN + 3 HCl;(B) for additional complexing AlCl3 + NH3 ⇋ AlCl3 · NH3 at substrate temperature which did not result in changes of yield above 900°C;(C) for AlCl3 · NH3 ⇋ AlN + 3 HCl corresponding to complete inhibition of dissociation near the substrate of the complex formed or preformed at lower temperature which resulted in considerably lower yields.A corresponding decrease of experimental results occurred within reactors having a long AlCl3–NH3‐mixing zone at 350°C or AlCl3 · NH3‐input with respect to a reactor with a short mixing zone near to the substrate. The dissociation of the complex present in the former two cases was inhibited considerably. – This investigations demonstrate the additional influence of homogeneous reactions, which has to be regarded for CVD especially with complexing reactants in connection with the role of reactor geometry, a problem being increasingly discussed at present.
Crystallographic relations in the FeZn system
Authors: Verplanke J. C. , Bastin G. F. , van Loo F. J. J. 
Published: July 2007

AbstractThe crystallographic relations between the various FeZn compounds have been investigated by means of single‐crystal X‐ray diffraction techniques. These techniques were applied to primary single crystals of each compound upon which after cooling a single crystalline layer of the neighbouring compound richer in zinc was grown. In this way it has been possible to determine relationships in the sequence α – Γ – Γ1 – δ:

No crystallographic relationship could be established for δ–ζ because it proved impossible to grow a single crystalline layer of ζ on δ. The apparently bad compatibility of the two lattices was reflected in the nucleation problems which were always encountered during efforts to grow ζ on δ. The influence of the relationships on the actually observed textures in the δ and ζ layers of hot dip galvanized specimens is discussed.
High‐Temperature Crystallization, Composition, Structure, and Certain Properties of Rare‐Earth Gallium Borates
Authors: Al'Shinskaya L. I. , Leonyuk N. I. , Timchenko T. I. 
Published: July 2007

AbstractSolution‐melts based on PbF2—B2O3 and Bi2O3—B2O3 were used in studying the stability regions and for growth, by way of spontaneous crystallization, of crystals up to 3 mm in size of twelve compounds having the general formula RGa3(BO3)4. All of these compounds are isostructural with carbonate mineral huntite. Their composition is highly dependent on that of the crystallization medium. The facing of the crystals is characterized by a small number of simple forms {1011}, {1120}, {2110}, and less frequently {0221}, {0112}, {4041}. The examined parameters include the IR spectra, luminescence spectra, heat of formation from oxides, harness (6 to 8 units on the Mohs scale) and others.
OD Interpretation of Pyroxenes
Authors: Sedlacek P. , Zedler A. , Reinecke K. 
Published: July 2007

AbstractThe structures of pyroxenes are interpreted as OD structures consisting of layers.The symmetry relations of the idealized structures of “high pyroxenes”, consisting of only one kind of silicate sheets are described by the OD groupoid family:magnified imageIn this case the tetrahedral layers (OD layers) are identical with silicate sheets and the octahedral layers (OD layers) are identical with the chemical octahedral sheets, apart from the fact, that the O atoms are considered to belong partly to one and partly to the other idealized layer.In the idealized pyroxene structures, which are called in this paper “low pyroxenes”, every second silicate sheet is of lower symmetry. A silicate sheet of higher symmetry is considered as an OD layer, called tetrahedral layer. An OD layer of the other kind, called compound layer, consists of one silicate sheet of lower symmetry with an octahedral sheet attached to it on either side. With this definition of the two kinds of layers, the OD groupoid family has the following symbol: magnified imagePolymorphism, disorder, twinning and parallel intergrowth are explained on this basis.
The crystallisation of alkaline‐earth metal oxides from metal chloride melts: Solubility‐temperature phase diagram analyses and preliminary experimental studies
Authors: Packter A. 
Published: July 2007

AbstractThe solubility v temperature phase diagrams for magnesium, calcium, strontium and barium oxide solutions, in lithium, sodium and potassium chloride melts and in the alkaline earth metal chloride melts, have been analysed. The solutions in the alkali metal chlorides are pseudo‐binary reciprocal ternary mixtures; the more soluble barium and strontium oxides showed small deviations, calcium oxide showed larger deviations while the extremely sparingly‐soluble magnesium oxide showed extensive deviations from ideality. These deviations were related to electrostatic interactions in solution, that depended in turn on some function of reciprocal solute and solvent caiton radii. The solutions in the alkalineearth metal chlorides are binary mixtures with MO · 4 MCl2 solvate formation. — Some preliminary crystallisation experiments were carried out, by slow cooling of saturated solutions in the metal chloride melts: calcium and strontium oxide crystallisation from lithium chloride melts and barium oxide crystallisation from all three alkali metal chloride melts would be worth further investigation.
Chemical lap polishing of PbTe and Pb1−xSnxTe crystals
Authors: Breitsameter B. , Hartmann W. , Löwe H. 
Published: July 2007

AbstractChemical lap polishing of PbTe and Pb1−xSnx Te crystals is investigated. A mixture of potassium hexacyanoferrate (III), sodium hydroxide, glycerol and water is used as a polish. The effect of various parameters of the process on the quality of the surface and on the rate of material removal is studied. The quality of the surface is strongly is strongly affected by the composition of the polish. The roughness increases with rising sodium hydroxide concentration but decreases with rising glycerol concentration. If the molar ratio of sodium hydroxide and potassium hexacyanoferrate (III) exceeds the value 0.5 etch figures are formed. The rate of material removal largely depends on the velocity of the relative movement between specimen and cloth, the rate of supply of polishing solution and on the concentration of sodium hydroxide.
A theoretical interpretation of the electrical behaviour of individual edge dislocations in Si as determined by combined EBIC/TEM studies
Authors: Ourmazd A. 
Published: July 2007

AbstractThe EBIC data obtained from individual edge and Frank partial dislocations in Si, and described in other publications, are related to defect parameters, such as the capture cross‐section for minority carriers, which determine electrical recombination properties of dislocations. A two stage model for the capture of minority carriers by dislocations is developed and shown to correctly account for the temperature‐dependence of the EBIC contrast obtained from these dislocations.
On the DLTS‐characterization of dislocation states in silicon
Authors: Szkiełko W. , Breitenstein O. , Pickenhein R. 
Published: July 2007

AbstractElectron traps revealing nonexponential kinetics of electron capturing were detected in DLTS spectra of dislocated silicon. Their apparent capture cross‐sections are dependent on temperature and on the filling state of the trap system. A model of deformationinduced damage in silicon is proposed.
The crystal and molecular structure of 1,12‐dibromododecane, C12H24Br2
Authors: Kulpe S. , Seidel I. , Szulzewsky K. , Steger U. , Steger E. 
Published: July 2007

AbstractThe α,ω‐dihaloalcanes could serve as model compounds for polyethylenes in further studies of infrared and Raman‐spectra. The 1,12‐dibromododecane, belonging to this class of compounds, has the monoclinic space group P 21/a with the cell parameters a = 24.8 Å, b = 5.40 Å, c = 5.50 Å, β = 99°, Z = 2. The preparation of crystals was very difficult. The crystal finally used gives only few and bad X‐ray data measured by film method (equiinclination Weissenberg). Therefore the accuracy of the structure determination is not high, but the result is reliable and has model character for related compounds.All molecules are ordered with their long molecular axes parallel to the (401) planes of the unit cell. There are alternating plane layers of bromine atoms on the one hand and aliphatic parts of the molecules on the other hand, both parallel to the (100)‐planes. This molecular arrangement explains well the spectroscopic and crystal optical properties of the structure and also of related compounds like 1,10‐dibromodecane and 1,18‐dibromooctadecane.
Improved methods of combining forecasts
Authors: Granger Clive W. J. , Ramanathan Ramu 
Published: July 2007

AbstractIt is well known that a linear combination of forecasts can outperform individual forecasts. The common practice, however, is to obtain a weighted average of forecasts, with the weights adding up to unity. This paper considers three alternative approaches to obtaining linear combinations. It is shown that the best method is to add a constant term and not to constrain the weights to add to unity. These methods are tested with data on forecasts of quarterly hog prices, both within and out of sample. It is demonstrated that the optimum method proposed here is superior to the common practice of letting the weights add up to one.
Collinearity and the use of latent root regression for combining GNP forecasts
Authors: Guerard John B. , Clemen Robert T. 
Published: July 2007

AbstractIn combining economic forecasts a problem often faced is that the individual forecasts display some degree of dependence. We discuss latent root regression for combining collinear GNP forecasts. Our results indicate that latent root regression produces more efficient combining weight estimates (regression parameter estimates) than ordinary least squares estimation (OLS), although out‐of‐sample forecasting performance is comparable to OLS.
Estimation procedures for structural time series models
Authors: Harvey A. C. , Peters S. 
Published: July 2007

AbstractA univariate structural time series model based on the traditional decomposition into trend, seasonal and irregular components is defined. A number of methods of computing maximum likelihood estimators are then considered. These include direct maximization of various time domain likelihood function. The asymptotic properties of the estimators are given and a comparison between the various methods in terms of computational efficiency and accuracy is made. The methods are then extended to models with explanatory variables.
Non‐linear state space models with partially specified distributions on states
Authors: Smith J. Q. 
Published: July 2007

AbstractThe author argues, through the discussion of several examples, why models like the power steady model (Smith 1979, 1981a) are attractive not only because of the simplicity of their one‐step‐ahead forecast distributions but also because they can be justified through sets of properties that any gradually evolving process may be expected to satisfy.
Forecasting time series with increasing seasonal variation
Authors: Bowerman Bruce L. , Koehler Anne'b. , Pack David J. 
Published: July 2007

AbstractFour options for modeling and forecasting time series data containing increasing seasonal variation are discussed, including data transformations, double seasonal difference models and two kinds of transfer function‐type ARIMA models employing seasonal dummy variables. An explanation is given for the typical ARIMA model identification analysis failing to identify double seasonal difference models for this kind of data. A logical process of selecting one option for a particular case is outlined, focusing on issues of linear versus non‐linear increasing seasonal variation, and the level of stochastic versus deterministic behavior in a time series. Example models for the various options are presented for six time series, with point forecast and interval forecast comparisons. Interval forecasts from data‐transformation models are found to generally be too wide and sometimes illogical in the dependence of their width on the point forecast level. Suspicion that maximum likelihood estimation of ARIMA models leads to excessive indications of unit roots in seasonal moving‐average operators is reported.
Recursive forecasting, smoothing and seasonal adjustment of non‐stationary environmental data
Authors: Young P. C. , Ng C. N. , Lane K. , Parker D. 
Published: July 2007

AbstractThe paper presents a unified, fully recursive approach to the modelling, forecasting and seasonal adjustment of non‐stationary time series and shows how it can be used as a flexible tool in the analysis of environmental data. The approach is based on time‐variable parameter (TVP) versions of various well‐known time‐series models and exploits the suite of novel, recursive filtering and fixed interval smoothing algorithms available in themicroCAPTAIN computer program. The practical utility of the analysis is demonstrated by an example based on the analysis of atmospheric CO2and sea surface temperature anomaly data.
Forecasting time series with outliers
Authors: Chen Chung , Liu Lon‐Mu 
Published: July 2007

AbstractTime‐series data are often contaminated with outliers due to the influence of unusual and non‐repetitive events. Forecast accuracy in such situations is reduced due to (1) a carry‐over effect of the outlier on the point forecast and (2) a bias in the estimates of model parameters. Hillmer (1984) and Ledolter (1989) studied the effect of additive outliers on forecasts. It was found that forecast intervals are quite sensitive to additive outliers, but that point forecasts are largely unaffected unless the outlier occurs near the forecast origin. In such a situation the carry‐over effect of the outlier can be quite substantial. In this study, we investigate the issues of forecasting when outliers occur near or at the forecast origin. We propose a strategy which first estimates the model parameters and outlier effects using the procedure of Chen and Liu (1993) to reduce the bias in the parameter estimates, and then uses a lower critical value to detect outliers near the forecast origin in the forecasting stage. One aspect of this study is on the carry‐over effects of outliers on forecasts. Four types of outliers are considered: innovational outlier, additive outlier, temporary change, and level shift. The effects due to a misidentification of an outlier type are examined. The performance of the outlier detection procedure is studied for cases where outliers are near the end of the series. In such cases, we demonstrate that statistical procedures may not be able to effectively determine the outlier types due to insufficient information. Some strategies are recommended to reduce potential difficulties caused by incorrectly detected outlier types. These findings may serve as a justification for forecasting in conjunction with judgment. Two real examples are employed to illustrate the issues discussed.
Modelling exchange rate dynamics new perspectives from the frequency domain
Authors: Nachane D. M. , Ray D. 
Published: July 2007

AbstractIn this paper the dynamics of foreign exchange rates is sought to be studied via new frequency domain techniques. Stationarity properties of the rates are analysed via a unit root test as well as a test based on the evolutionary spectrum. Linearity and Gaussianity are analysed via bispectral tests and compared with the more frequently employed time domain tests, such as the McLeod‐Li and Tsay tests. Finally, an evaluation of the out‐of‐sample forecasting properties for eight methods—Random Walk, ARMA, Bilinear, State dependent model, dynamic linear model, ARCH, GARCH, and Garch‐in‐mean—is made. The methods used here seem to shed a great deal of light on hitherto neglected aspects of exchange rate dynamics.
Disaggregation of annual time‐series data to quarterly figures: A comparative study
Authors: Chan Wai‐Sum 
Published: July 2007

AbstractIn this paper we consider some of the prominent methods that are available in the literature for the problem of disaggregating annual time‐series data to quarterly figures. The procedures are briefly described and illustrated through a real data set. The performances of the methods are compared in a Monte Carlo study. The results indicate that the complicated model‐based procedure is usually superior to other non‐model‐based alternatives in the large sample situations. Based on the simulation results, we make some recommendations regarding the use of these methods.
Time‐series analysis, forecasting and econometric modelling: The structural econometric modelling, time‐series analysis (SEMTSA) approach
Authors: Zellner Arnold 
Published: July 2007

AbstractIn this paper an account of our experiences in modelling and forecasting the annual output growth rates of 18 industrialized countries is presented. A structuraleconometric modelling, rime‐series analysis (SEMTSA) approach is described and contrasted with other approaches. Theoretical and applied results relating to variable and model selection and point and turning‐point forecasting are discussed. A summary of results and directions for future research concludes the paper.
Towards a taxonomy of forecast error measures a factor‐comparative investigation of forecast error dimensions
Authors: Mathews Brian P. , Diamantopoulos Adamantios 
Published: July 2007

AbstractThis study explores the nature of information conveyed by 14 error measures drawn from the literature, using real‐life forecasting data from 691 individual product items over six quarterly periods. Principal components analysis is used to derive factor solutions that are subsequently compared for two forecasting methods, a version of Holt's exponential smoothing, and the random walk model (Naive 1). The results reveal four underlying forecast error dimensions that are stable across the two factor solutions. The potentially confounding influence of sales volume on the derived error dimensions is also explored via correlation analysis.
Business cycle analysis and forecasting with a structural vector auto regression model for wales
Authors: Ioannidis C. , Laws J. , Matthews K. , Morgan B. 
Published: July 2007

AbstractRecent innovations in the Welsh economy have led to the view that the region's economy is likely to exhibit differential responses to financial and external shocks compared to the rest of the UK. This is examined with the aid of a structural VAR forecasting model for Wales.
Reconfigurable combined forecasts in a non‐stationary inflationary environment
Authors: Volkov V. Ya. , Gladkov Y. U. M. 
Published: July 2007

AbstractThis paper presents a composite method for non‐stationary economic forecasts, incorporating reconfigurable exponential trend extraction and linear combinations of parabolic and spectral estimators for short‐term prediction. The method automatically identifies the points of time series misalignment induced by sharp environmental changes. An application to the problem of hard currency exchange rate prediction in Russia is presented.
Hierarchical redundancy for two‐dimensional orthogonal arrays using defect‐tolerant replacement circuits
Authors: Tsuda Nobuo 
Published: July 2007

AbstractHierarchical redundancy using defect‐tolerant replacement circuits is proposed as a means to increase the yield of large‐area LSIs (WSIs) with mesh‐connected array structures. The defect‐tolerant replacement circuits can be constructed by using direct‐connection paths and distributed switches in basic k‐out‐of‐n redundancy schemes.When the proposed redundancy configurations are applied to two‐dimensional orthogonal‐array WSIs, they reduce the number of switches not covered by any spare replacements.An estimate of defect tolerance indicates that the proposed redundancy configurations can increase the integration scale of under 1‐μm CMOS design circuits to about 400 times that of general nonredundant LSIs.
A parallel branch‐and‐bound algorithm for integer linear programming and its implementation on a distributed multiprocessor
Authors: Ikegami Atsuko , Aoyagi Katsuhiro , Iizuka Hajime 
Published: July 2007

AbstractThis paper describes a parallel branch‐and‐bound algorithm for general integer linear programming problems and its implementation on a distributed memory multiprocessor nCUBE2.With a branch‐and‐bound algorithm, the amount of computation on each search tree node varies, and in general, is large. This has led to development of an effective communication strategy for the algorithm presented herein. Its implementation and performance evaluation also are described.The results show that the more difficult the problem instances become in terms of time to solve on a sequential computer, the more efficient the algorithm presented here proves to be.