bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rural local government finance in Kenya: The case of Murang'a County Council
Authors: Smoke Paul 
Published: July 2007

AbstractThe Murang'a County Council is recognized in Kenya as one of the country's most effective rural local authorities. Compared to other county councils, Murang'a raises substantial revenues and provides a wide variety of services. This case study presents some background on the local economy of Murang'a District, details available information about the county council's excellent fiscal performance, and highlights some of the major factors behind the effectiveness of Murang'a in resource mobilization and service delivery.
Decentralization by default: Local governance and the view from the village in The Gambia
Authors: Davis Daniel , Hulme David , Woodhouse Philip 
Published: July 2007

AbstractPolicies to decentralize government activities in The Gambia have been on the agenda for more than a decade but no decisions have been taken. During this period the quality of government services to rural areas has declined dramatically. The linchpin of provincial administration, the divisional commissioner, has become redundant as far as development is concerned. The activities of line ministries have deteriorated as their expenditures have been reduced and they lack the funds to permit staff to operate at village level. Area councils that were previously regarded as wasteful are now totally discredited. Village development committees (VDCs) have been formed, but the results are mixed and often they are ineffective. By default, decentralization in the 1980s and early 1990s in The Gambia has been achieved by non‐governmental organizations (NGOs), which have rapidly grown in number and significance. This article explores the perceptions of villagers in The Gambia about the various organizations that are meant to serve their needs. Its conclusion speculates on proposals to implement a new decentralization policy in the country and points to the need for aid agencies to adopt a less simplistic approach to the issue of local governance.
Field Equations in Quantum Electrodynamics
Authors: Brandt Richard A. 
Published: July 2007

AbstractA formulation of quantum electrodynamics is presented, based on finite local field equations. These Dirac and Maxwell equations have the usual form except that the current operators f(x) and jμ (x) are explicitly expressed as local limits of sums of non‐local field products and suitable subtraction terms. These limits are shown to exist and to yield finite operators in the sense that the iterative solutions to the field equations are equivalent to conventional renormalized perturbation theory. The various invariance properties of the theory, including Lorentz invariance, gauge invariance, charge conjugation invariance, and renormalization invariance, are discussed and related directly to the field equations and current definitions. Initially only the general forms of the currents, based on dimensional arguments, are given. The electric current, for example, contains the (suitably defined) term :A3(x) :.The corresponding field equations are used to derive renormalized Dyson‐Schwinger‐type integral equations for the renormalized proper part functions ∑, IIμν, Λμ, and Xαβγδ (the four‐photon vertex function), etc. Application of the boundary conditions ∑(p̀ = m) = ∑′(p̀ = m) = II(O) = II′(O) = II″(O) = Λ(p̀ = m, o) = X(O, O, O, O) = O completely specifies the current operators. Consistency is established by deriving the same equations from rigorous renormalization theory so that their iterative solutions are proved to reproduce the correct renormalized perturbation expansion.The electric current operator is exhibited in a manifestly gauge invariant form and in a form which is manifestly negative under charge conjugation. It is shown, in fact, that much of jμ (x) can be determined directly from the requirements of gauge invariance and charge conjugation covariance, without recourse to the integral equations. It is suggested that equal time commutation relations can serve to similarly specify the rest of the current.
Furry Picture for Quantum Electrodynamics with Pair‐Creating External Field
Authors: Fradkin E. S. , Gitman D. M. 
Published: July 2007

AbstractIn the paper the perturbation theory is constructed for QED, for which the interaction with the external pair‐creating field is kept exactly. An explicit expression for the perturbation theory causal electron propagator is found. Special features of usage of the unitarity conditions for calculating the total probabilities of radiative processes in the case are discussed. Exact Green functions are introduced and the functional formulation is discussed. Perturbation theory for calculating the mean values of the Heisenberg operators, in particular, of the mean electromagnetic field is built in the case under consideration. Effective Lagrangian which generates the exact equation for the mean electromagnetic field is introduced. Functional representations for the generating functionals introduced in the paper are discussed.
Hadronic Production of Heavy QQ Bound States
Authors: Escobar C. O. , Malbouisson A. P. C. , Santoro A. F. S. , Shellard R. C. , Souza M. H. G. 
Published: July 2007

AbstractSeveral mechanisms for the production of heavy QQ bound states are reviewed. A systematic comparison between model predictions and experimental results is presented. The various theoretical and experimental uncertainties are discussed.
Pion Coupling to Nuclei
Authors: Dumbrajs Olgierd 
Published: July 2007

AbstractThe concept of the pion‐nucleus coupling constants is discussed. Methods of their determination are reviewed. These include: forward dispersion relations, extrapolation of differential cross sections to the poles in the angular variable, analysis of data on electromagnetic form factors with the use of the PCAC and CVC hypotheses, pion photoproduction at threshold and low‐ernergy theorems. Our present knowledge of the pion coupling to the He, Li, Be, C, N and O nuclei is summarized.
Dielectric Behaviour of Liquid Crystals
Authors: Kresse H. 
Published: July 2007

AbstractThe influence of the molecule structure on the dielectric anisotropy of nematic liquid crystals was experimentally investigated and discussed from the point of view of the Maier‐Meier theory. Further, the reorientation time of the dipoles in different smectic phases was measured and correlated to the structure of the phases. Some technical aspects are discussed in connection with the dielectric relaxation phenomenon.
Reliability critical thermal model for double‐drift IMPATT diodes on diamond heat sinks
Authors: Csanky G. 
Published: July 2007

AbstractA thermal model of double‐drift IMPATT diodes on diamond heat sinks has been developed. The thermal model approximates the temperature‐dependent thermal conductivities of Si and diamond (Type II) by means of simple empirical formulae. The application of the thermal model to three IMPATT diode lots indicates that under life test, junction temperatures are greater than 700°C, and that the metal/Si interface temperatures exceed 500°C. An explanation of the failure mechanism is presented. Designs that result in a lower junction temperature are proposed.
System reliability prediction based on historical data
Authors: Usher John S. , Alexander Suraj M. , Thompson John D. 
Published: July 2007

AbstractThis paper describes the development and implementation of a computerized reliability prediction model at the IBM facility located in Research Triangle Park, North Carolina. Through the analysis of historical life‐test data, the model provides maximum likelihood estimates of the assumed Weibull life distributions of various types of components. The resulting component life distribution estimates are used to predict the reliability of new system configurations. This approach is based upon the well‐known theory of competing risks. Our model, however, is unique in that it allows for the analysis of a pooled set of life data, i.e. life data from different types of systems, to obtain component estimates. This feature greatly generalizes the competing risks framework and hence offers advantages over the more traditional approach. We present the model and discuss various issues that were found to be critical to its successful implementation at IBM.
Increasing importance of effects of marginal parts on reliability
Authors: Ganter William A. 
Published: July 2007

AbstractIn this paper, marginal parts are equated with low quality and low reliability. Marginal parts can be shown to cause errors in some products during tests. They are also a cause of field failures in these products. Although marginal parts causes still have a random failure time component, they have a much lower amount of variation than our traditional failure causes, hidden flaws. I give marginal parts a measurable definition. If marginal effects can be established for a product, then this knowledge can be used to improve reliability. Some examples of products where I believe this marginal effect holds are discussed in this paper. Such marginal effects on reliability are gaining more and more importance in systems that are increasing in complexity. A strong point in applying the marginal parts theory framed in this paper is that it can be readily subjected to statistical testing to see if it holds or not for any particular product.
Infant mortality modelling for vlsi devices using graphical estimation
Authors: Stoltze Paul L. 
Published: July 2007

AbstractThis paper presents a practical methodology for the routine analysis of VLSI infant mortality data. Device families are modelled using established graphical parameter estimation techniques, and the model parameters are applied to individual device types within the family. Burn‐in requirements are calculated to achieve a desired early life reliability level. A technical summary of the methods is presented, and a small data set is analysed as an example. The analysis results from three large device families are also presented.
Optoelectronics reliability
Authors: Ikegami Tetsuhiko , Fukuda Mitsuo 
Published: July 2007

AbstractThis paper reviews degradation modes and reliability in several kinds of InGaAsP/InP lasers and photodetectors used in optical fibre transmission systems. From the viewpoint of degradation mechanisms, BH type Fabry–Perot lasers, DFB lasers, a 0.98 μm strained quantum well InGaAs/GaAs laser, and InGaAs PIN photodetectors and APDs are reviewed.
Reliability improvement of electronic circuits based on physical failure mechanisms in components
Authors: Brombacher A. C. , de Boer H. A. , Bennion M. , Fennema P. H. , Herrmann O. E. 
Published: July 2007

AbstractTraditionally the position of reliability analysis in the design and production process of electronic circuits is a position of reliability verification. A completed design is checked on reliability aspects and either rejected or accepted for production. This paper describes a method to model physical failure mechanisms within components in such a way that they can be used for reliability optimization, not after, but during the early phase of the design process. Furthermore a prototype of a CAD software tool is described, which can highlight components likely to fail and automatically adjust circuit parameters to improve product reliability.
Methods for the continuous assessment of reliability of specialized equipment
Authors: Watkins A. J. , Leech D. J. 
Published: July 2007

AbstractThis paper is concerned with the assessment of reliability for equipment which is highly specialized. Of particular interest is the analysis of field data early in the life of the fleet of such equipment. Factors affecting the data underlying assessments are outlined, and a basic statistical model for describing these data is introduced. Methods of assessment of equipment reliability, and the precision of such assessments, are discussed, examples of data from this basic model are analysed, and further examples illustrate the role of model parameters. The model may also be used to analyse incomplete data sets, and we consider the penalty incurred at different levels of incompleteness. The paper concludes with a discussion outlining further possible modifications and refinements to the basic model.
Transition from quality circles to total involvement in semiconductor manufacturing
Authors: Derry Carol A. 
Published: July 2007

AbstractEight years of experience with quality circles has shown a progression toward the achievement of total quality. Significant positive results have led to the evolution from a voluntary programme to the implementation of a non‐voluntary programme that includes functional supervisors. Each team meets for an hour per week during normal work hours as an integral part of the job. Over 83 per cent of manufacturing and support groups employee participation has been recorded to date and at present 62 teams are functioning. This article will present the details of this programme's progress towards quality excellence.
Good quality at low cost: Trends in quality assurance
Authors: Fleischhammer Werner 
Published: July 2007

AbstractFor as long as electronic devices have been produced the relationship between the costs and benefits of quality assurance has been discussed. At present this relationship is influenced by the increase in the complexity of integrated circuits and by the growing extent of automation in production. In this paper a way is presented showing how the cost of quality assurance can be decreased without loss of quality. Six steps to achieving this goal are described.
Ultrasonic microscope investigations of die attach quality and correlations with thermal resistance
Authors: Pfannschmidt Gabriele 
Published: July 2007

AbstractIn the semiconductor industry the use of ultrasonic microscopes for evaluating the integrity of the bond between adjacent surfaces has increased dramatically over the last few years. These instruments are rapidly becoming an acceptable diagnostic tool in the QC laboratory and new specifications have been written incorporating them into MIL requirements. Especially in the non‐destructive investigation of plastic encapsulated ICs for delaminations, cracks, voids, and die‐bonding faults ultrasonic microscopy has great advantages. The main equipment used is SLAM (or through transmission mode acoustic microscope) with a frequency range of 10–200 MHz and C‐SAM (or reflective mode acoustic microscope) working in the range 5–100 MHz. In this paper, standard measurements of die attach quality and thermal resistance are correlated with C‐SAM results. A general correlation between the amount of delamination and the measured thermal resistance was found.
Electromigration at gold–aluminium interfaces and in thin aluminium tracks
Authors: Vanhecke B. , de Schepper L. , de Ceuninck W. , D'haeger V. , D.'olieslaeger M. , Beyne E. , Stals L. , Roggen J. 
Published: July 2007

AbstractThe in situ method to study accelerated ageing of electronic interconnections under current stress has been applied to (a) Au ball bonds on A11% Si metallization, and (b) thin aluminium tracks. For the Au ball bonds, it has been shown that direct current stresses above 108 Am−2 cause electromigration effects at the Au‐Al interface, and that the ageing behaviour depends on the direction of the applied direct current stress. It was also shown that the addition of 1 per cent Cu to the metallization strongly retards void formation, and hence open contact failure. For the thin aluminium tracks, it has been shown that the early stage of electromigration, which can be studied accurately with the in situ technique, is closely related to the stress relaxation within the track. It is therefore concluded that the kinetics of electromigration can only be described if the kinetics of stress relaxation are well understood.
Improved structural reliability assessment using non‐linear regression techniques to process raw fatigue crack growth test data
Authors: Stavrakakis G. S. 
Published: July 2007

AbstractA new method is proposed to process raw fatigue crack growth (FCG) test data for estimating the parameters of any crack propagation (FCG) model. This method is based on iterative minimization techniques for non‐linear regression, extensively available in the literature. The method presented here permits a significantly reduced contribution of the variability inherent in the usual raw FCG data processing techniques to the predictions of the crack length distributions derived by any analytical FCG model and, consequently, improved structural reliability assessment is achieved.
Thermoreflectance optical test probe for the measurement of current‐induced temperature changes in microelectronic components
Authors: Claeys W. , Dilhaire S. , Quintard V. , Dom J. P. , Danto Y. 
Published: July 2007

AbstractWe have developed an optical laser probe for the measurement of absolute surface temperature changes in integrated circuits. The experimental method is based upon thermoreflectance, which is the change in reflectance due to surface temperature changes of the device. A laser beam is focused upon a small spot of an operating circuit. The reflected intensity is recorded upon a photodiode in synchronism with the circuit periodic excitation signal. We calibrated the device by developing a simple analytical model to calculate the surface temperature behaviour of a silicon resistive structure we tested. The value we derived for the relative reflectance temperature coefficient of silicon is in excellent agreement with the value from the literature. The results show the laser probe to be a fast surface thermometer (DC to 10 MHz), with excellent lateral resolution (1 μm), with high sensitivity (10−3°C) and large dynamics (ΔT: 102 to 10−3°C).
Estimating process capability indices for non‐normal pearsonian populations
Authors: Pearn W. L. , Chen K. S. 
Published: July 2007

AbstractClements1 introduced a method for calculating the estimators of two classical process capability indices (PCI), Cp and Cpk, for non‐normal Pearsonian populations. Pearn and Kotz2 applied Clements' method to obtain first approximation estimators of PCIs for non‐normal populations to the two more advanced PCIs, Cpm and Cpmk developed by Chan et al.3 and Pearn et al.4 In this paper, we consider a different approach for calculating the estimators of the four PCIs. The new approach may be viewed as a modification of Clements' method. Comparisons between Clements' and the proposed new methods are also provided.
A multichannel CSMA/CD method in bus‐type local area networks
Authors: Nomura Yoshifumi , Nakanlshl Yoshiro , Okada Hiromi 
Published: July 2007

AbstractThe CSMA/CD method, one of the communication schemes for bus‐type LANs, has problems with respect to transmission capability and its function. This paper presents an access control method named multichannel CSMA/CD for local area networks. In this method, CSMA/CD combined with a new load distribution mechanism and channel selection function is extended to multichannel organization. This method aims at LANs having high performance and multiple functions. As a result of performance evaluation, multichannel CSMA/CD is shown to be superior to the original CSMA/CD with respect to (1) total transmission capacity, (2) throughput‐delay characteristic performance, (3) channel stability and (4) adaptability to various kinds of user demands in networks.
Fusion algorithm not affected by the picture frame
Authors: Suzuki Satoshi , Abe Keiichi 
Published: July 2007

AbstractThis paper discusses the properties and the algorithms of the fusion operations, which are one of the fundamental techniques of binary image processing. First, a theoretical discussion is made for infinitely spread images, deriving several properties for the fusion operations. Those properties indicate the equivalence among the fusion operations and their iterations and combinations. Since the actual input images are finite, those properties are not satisfied by a simple algorithm due to the effect of the picture frame. This paper presents algorithms not affected by the picture frame for the general‐purpose sequential computers and for the dedicated parallel‐processing hardwares. Those algorithms perform the fusion operation by executing the first operation in the fusion (that is, the expansion or the contraction) together with the distance transformation, and by performing the second operation using the distance information obtained in the first. The proposed algorithms have the feature that most of the properties for infinite images also apply to images of finite size. With this feature, the proposed algorithms are shown to be suited to parallel processing with a small number of processors.
Measurement of three‐dimensional position and orientation of a plane‐like object
Authors: Nonmember Heng‐Li Guo , Yachida Masahiko , Tsuji Saburo 
Published: July 2007

AbstractThis paper describes a method to determine the 3‐D position and orientation of a plane‐like object. The system first extracts edges of the plane‐like object and its shadow cast on a working table by an ideal point light source. Utilizing the shadow informaton effectively, it estimates the 3‐D positions of several boundary points, from which the position and orientation of the plane‐like object are then determined. An application of this method, measurement of the 3‐D position, and orientation of a printed circuit board, is presented. The errors in measuring the position and orientation are about 1% of the size of sight and 4 degrees, respectively. The result is sufficient for a robot hand to manipulate the printed circuit board.
Management of time‐series data by feature description based upon generative grammar, fitting ARMA model to EEG signals
Authors: Tokinaga Shozo 
Published: July 2007

AbstractIn the retrieval of stored time‐series data, as means for improving the retrieval efficiency and for the pre‐processing of classification, it is effective to utilize the time‐domain characteristics of the time‐series data as the key in the retrieval. This paper presents a method which describes the feature of elec‐troencephalographic time‐series in a simple linguistic form and to perform data management based on that description. First, the ARMA model is applied to the general non‐stationary time‐series which is partitioned into small intervals based on the spectrum estimation error. At the same time, for the cases where a sporadic (transient) waveform is included, the transient wave is detected effectively by adaptively modifying the input to the model. Then identifying the class of the transient wave using recognition procedures such as smoothing, the features of EEG are determined for the background and the transient waves. A linguistic expression is derived by applying predetermined production rules to those features. The properties of the linguistic expression are discussed, together with the reproducibility of the original data time‐series and the compression of the original data. This indicates that the proposed method is a simple and effective means of representing EEG. Finally, a method is described for retrieval of time‐series data based on linguistic expression, which can cope with the ambiguity of expressions.
An edge detection algorithm of color images using the reduction of brightness and chroma
Authors: Agui Takeshi , Nakajima Masayuki , Sugita Atsushi 
Published: July 2007

AbstractIn the present layout scanner, the operations for changing color partially, or extracting a portion of it, have been done interactively by specifying the location through a digitizer. Usually, image analysis techniques and artificial intelligence techniques are applied to region extraction and region matching operations. This paper describes an edge detection algorithm which is the most basic operation of color image processing.First, attention is given to effective gray scale intensity analysis of the gray level image. Then the concept of the reduction of brightness and chroma is considered as an addition of the differences in terms of hue and chroma to the differences in terms of brightness. Based on that concept, the difference equation is derived and the edge detection experiments are reported.