bluuebunny/crossref_metadata_2025 huggingface dataset:
Source localization in the presence of internal waves
Authors: Baer Ralph N. , Collins Michael D.
Published: October 2005

The possibility of determining the location of an acoustic source in the presence of internal waves is investigated. Source localization problems require environmental information as inputs. Internal waves cause uncertainties in the sound speed field. In previous work [J. Acoust. Soc. Am. 90, 1410–1422 (1991)], it was found that a source can often be localized in an uncertain environment by including environmental parameters in the search space and tweaking them, but usually not determining their true values. This is possible due to a parameter hierarchy in which the source position is more important than the environmental parameters. The parameter hierarchy is shown to also apply to uncertainties associated with internal waves. Due to differences in the nature of the parameter space, this problem is solved with a statistical approach rather than a parameter search technique such as simulated annealing.
Time-reversal-based imaging and inverse scattering of multiply scattering point targets
Authors: Devaney Anthony J. , Marengo Edwin A. , Gruber Fred K.
Published: October 2005

The treatment of time-reversal imaging of multiply scattering point targets developed by the present authors in Gruber et al. [“Time-reversal imaging with multiple signal classification considering multiple scattering between the targets,” J. Acoust. Soc. Am., 115, 3042–3047 (2004)] is reformulated and extended to the estimation of the target scattering strengths using the Foldy–Lax multiple scattering model. It is shown that the time-reversal multiple signal classification (MUSIC) pseudospectrum computed using the background Green function as the steering vector yields accurate estimates of the target locations, even in the presence of strong multiple scattering between the targets, and that the target scattering strengths are readily computed from the so-determined target locations using a nonlinear iterative algorithm. The paper includes computer simulations illustrating the theory and algorithms presented in the paper.
Source of the North Pacific “boing” sound attributed to minke whales
Authors: Rankin Shannon , Barlow Jay
Published: October 2005

During a recent cetacean survey of the U.S. waters surrounding the Hawaiian Islands, the probable source of the mysterious “boing” sound of the North Pacific Ocean was identified as a minke whale, Balaenoptera acutorostrata. Examination of boing vocalizations from three research surveys confirms previous work that identified two distinct boing vocalization types in the North Pacific. The eastern boing (n=22) has a pulse repetition rate of 92s−1 and a duration of 3.6s and was found only east of 138°W. The central boing (n=106) has a pulse repetition rate of 115s−1 and a duration of approximately 2.6s and was found only west of 135°W. Central boing vocalizations produced by a single source (n=84) indicate that variation in repetition rate and duration of the calls of the individual were not significantly different than the variation among individuals of the same boing type. Despite a slight latitudinal overlap in the vocalizations, pulse repetition rates of the eastern and central boings were distinct.
The ensemble statistics of the vibrational energy density of a random system subjected to single point harmonic excitation
Authors: Langley R. S. , Cotoni V.
Published: October 2005

This paper is concerned with the ensemble statistics of the energy density of a random system subjected to a harmonic point load. Both the mean and variance of the reverberant energy density (i.e., the total response minus the direct field) are investigated. It is shown that the ensemble average of the reverberant energy density is not spatially homogeneous, but rather the value at the drive point is between two and three times the spatially averaged value, depending on the modal overlap factor. This result is closely analogous to established results regarding the case of transient excitation. Expressions are also derived for the relative variance of the reverberant energy density both remote from the drive point and at the drive point, and a number of anomalies are found in existing results. A comparison is made with simulation results for a randomized plate, and this comparison highlights the importance of the ensemble size considered in the simulations. The present analysis is based on a random point process model of the system natural frequencies, and both Gaussian orthogonal ensemble (GOE) statistics and Poisson statistics are considered.
Doubly focused backscattering from finite targets in an Airy caustic formed by a curved reflecting surface
Authors: Dzikowicz Benjamin R. , Marston Philip L.
Published: October 2005

Caustics can be formed in the water column when sound scatters off a curved-reflecting surface such as the ocean floor or surface. The simplest caustic is an Airy caustic formed by the merging of two rays. Small targets lying in or near Airy caustics have backscattered echoes that can be focused both to the target and upon return. For a point target, the doubly focused backscattering amplitude is proportional to the square of an Airy function whose argument depends on the target location through the changes in relative return times of contributing rays. For a finite sized target, the symmetry is broken and the amplitude unfolds into a hyperbolic umbilic catastrophe. The arguments for the hyperbolic umbilic function are calculated using the relative return times of transient echoes. These doubly focused echoes can lead to amplitudes larger than that of direct or singly focused echoes (echoes which focus once, either to the target or upon return). Experiments using a cylindrical half-pipe as a reflecting surface confirm these predictions.
The interaction of glottal-pulse rate and vocal-tract length in judgements of speaker size, sex, and age
Authors: Smith David R. R. , Patterson Roy D.
Published: October 2005

Glottal-pulse rate (GPR) and vocal-tract length (VTL) are related to the size, sex, and age of the speaker but it is not clear how the two factors combine to influence our perception of speaker size, sex, and age. This paper describes experiments designed to measure the effect of the interaction of GPR and VTL upon judgements of speaker size, sex, and age. Vowels were scaled to represent people with a wide range of GPRs and VTLs, including many well beyond the normal range of the population, and listeners were asked to judge the size and sex/age of the speaker. The judgements of speaker size show that VTL has a strong influence upon perceived speaker size. The results for the sex and age categorization (man, woman, boy, or girl) show that, for vowels with GPR and VTL values in the normal range, judgements of speaker sex and age are influenced about equally by GPR and VTL. For vowels with abnormal combinations of low GPRs and short VTLs, the VTL information appears to decide the sex/age judgement.
Optimal virtual sensing for active noise control in a rigid-walled acoustic duct
Authors: Petersen Dick , Zander Anthony C. , Cazzolato Ben S. , Hansen Colin H.
Published: October 2005

The performance of local active noise control systems is generally limited by the small sizes of the zones of quiet created at the error sensors. This is often exacerbated by the fact that the error sensors cannot always be located close to an observer’s ears. Virtual sensing is a method that can move the zone of quiet away from the physical location of the transducers to a desired location, such as an observer’s ear. In this article, analytical expressions are derived for optimal virtual sensing in a rigid-walled acoustic duct with arbitrary termination conditions. The expressions are derived for tonal excitations, and are obtained by employing a traveling wave model of a rigid-walled acoustic duct. It is shown that the optimal solution for the virtual sensing microphone weights is independent of the source location and microphone locations. It is also shown that, theoretically, it is possible to obtain infinite reductions at the virtual location. The analytical expressions are compared with forward difference prediction techniques. The results demonstrate that the maximum attenuation, that theoretically can be obtained at the virtual location using forward difference prediction techniques, is expected to decrease for higher excitation frequencies and larger virtual distances.
Underwater temporary threshold shift in pinnipeds: Effects of noise level and duration
Authors: Kastak David , Southall Brandon L. , Schusterman Ronald J. , Kastak Colleen Reichmuth
Published: October 2005

Behavioral psychophysical techniques were used to evaluate the residual effects of underwater noise on the hearing sensitivity of three pinnipeds: a California sea lion (Zalophus californianus), a harbor seal (Phoca vitulina), and a northern elephant seal (Mirounga angustirostris). Temporary threshold shift (TTS), defined as the difference between auditory thresholds obtained before and after noise exposure, was assessed. The subjects were exposed to octave-band noise centered at 2500Hz at two sound pressure levels: 80 and 95dB SL (re: auditory threshold at 2500Hz). Noise exposure durations were 22, 25, and 50min. Threshold shifts were assessed at 2500 and 3530Hz. Mean threshold shifts ranged from 2.9–12.2dB. Full recovery of auditory sensitivity occurred within 24h of noise exposure. Control sequences, comprising sham noise exposures, did not result in significant mean threshold shifts for any subject. Threshold shift magnitudes increased with increasing noise sound exposure level (SEL) for two of the three subjects. The results underscore the importance of including sound exposure metrics (incorporating sound pressure level and exposure duration) in order to fully assess the effects of noise on marine mammal hearing.
Acoustic signals of underwater explosions near surfaces
Authors: Krieger John R. , Chahine Georges L.
Published: October 2005

Underwater explosions are conventionally identified and characterized by their seismic and/or acoustic signature based on spherical models of explosion bubbles. These models can be misleading in cases where the bubble is distorted by proximity to the free surface, the bottom, or to a solid object. An experimental and numerical study of the effects of various nearby surfaces on the bubble’s acoustic signature is presented. Measurements from high-speed movie visualizations and acoustic signals are presented which show that the effect of proximity to a rigid surface is to increase the first period, weaken the first bubble pulse, and affect significantly the second period, resulting in a peak value at standoffs of the same order as the maximum bubble radius. These results are compared to results under a free surface, over a bed of sand, and over a cavity in a rigid surface. In all cases, the first period is increasingly lengthened or shortened as the motion of fluid around the bubble is increasingly or decreasingly hindered. The effect of bubble distortion is to weaken the first bubble pulse and increase the bubble size and the duration of the second cycle.
Intelligibilities of 1-octave rectangular bands spanning the speech spectrum when heard separately and paired
Authors: Warren Richard M. , Bashford James A. , Lenz Peter W.
Published: October 2005

There is a need, both for speech theory and for many practical applications, to know the intelligibilities of individual passbands that span the speech spectrum when they are heard singly and in combination. While indirect procedures have been employed for estimating passband intelligibilities (e.g., the Speech Intelligibility Index), direct measurements have been blocked by the confounding contributions from transition band slopes that accompany filtering. A recent study has reported that slopes of several thousand dBA∕octave produced by high-order finite impulse response filtering were required to produce the effectively rectangular bands necessary to eliminate appreciable contributions from transition bands [Warren et al., J. Acoust. Soc. Am. 115, 1292–1295 (2004)]. Using such essentially vertical slopes, the present study employed sentences, and reports the intelligibilities of their six 1-octave contiguous passbands having center frequencies from 0.25to8kHz when heard alone, and for each of their 15 possible pairings.
A probability density function method for acoustic field uncertainty analysis
Authors: James Kevin R. , Dowling David R.
Published: October 2005

Acoustic field predictions, whether analytical or computational, rely on knowledge of the environmental, boundary, and initial conditions. When knowledge of these conditions is uncertain, acoustic field predictions will also be uncertain, even if the techniques for field prediction are perfect. Quantifying acoustic field uncertainty is important for applications that require accurate field amplitude and phase predictions, like matched-field techniques for sonar, nondestructive evaluation, bio-medical ultrasound, and atmospheric remote sensing. Drawing on prior turbulence research, this paper describes how an evolution equation for the probability density function (PDF) of the predicted acoustic field can be derived and used to quantify predicted-acoustic-field uncertainties arising from uncertain environmental, boundary, or initial conditions. Example calculations are presented in one and two spatial dimensions for the one-point PDF for the real and imaginary parts of a harmonic field, and show that predicted field uncertainty increases with increasing range and frequency. In particular, at 500Hz in an ideal 100m deep underwater sound channel with a 1m root-mean-square depth uncertainty, the PDF results presented here indicate that at a range of 5km, all phases and a 10dB range of amplitudes will have non-negligible probability. Evolution equations for the two-point PDF are also derived.
Phonetic training with acoustic cue manipulations: A comparison of methods for teaching English /r/-/l/ to Japanese adults
Authors: Iverson Paul , Hazan Valerie , Bannister Kerry
Published: October 2005

Recent work [Iverson et al. (2003) Cognition, 87, B47–57] has suggested that Japanese adults have difficulty learning English /r/ and /l/ because they are overly sensitive to acoustic cues that are not reliable for /r/-/l/ categorization (e.g., F2 frequency). This study investigated whether cue weightings are altered by auditory training, and compared the effectiveness of different training techniques. Separate groups of subjects received High Variability Phonetic Training (natural words from multiple talkers), and 3 techniques in which the natural recordings were altered via signal processing (All Enhancement, with F3 contrast maximized and closure duration lengthened; Perceptual Fading, with F3 enhancement reduced during training; and Secondary Cue Variability, with variation in F2 and durations increased during training). The results demonstrated that all of the training techniques improved /r/-/l/ identification by Japanese listeners, but there were no differences between the techniques. Training also altered the use of secondary acoustic cues; listeners became biased to identify stimuli as English /l/ when the cues made them similar to the Japanese /r/ category, and reduced their use of secondary acoustic cues for stimuli that were dissimilar to Japanese /r/. The results suggest that both category assimilation and perceptual interference affect English /r/ and /l/ acquisition.
Transmission loss of viscoelastic materials containing oriented ellipsoidal coated microinclusions
Authors: Haberman Michael R. , Berthelot Yves H. , Cherkaoui Mohammed
Published: October 2005

The three-phase self-consistent (SC) micromechanical model of Cherkaoui et al. [J. Eng. Mater. Technol. 116, 274–278 (1994)] is employed to model the anisotropic effects induced by identically oriented, coated, and ellipsoidal microinclusions embedded in a viscoelastic matrix. Numerical predictions of the lossy and anisotropic behavior of the viscoelastic composite material are obtained. This study is an extension of a previous paper [J. Acoust. Soc. Am. 112 (5), 1937–1943 (2002)], where the agreement of the micromechanical approach with the long wavelength scattering model of Baird et al. [J. Acoust. Soc. Am. 105 (3), 1527–1538 (1999)] was demonstrated for the case of spherical inclusions. The use of the SC model for the special case of a biphase effective material is also considered and compared with the complex bounds available in the literature. Parametric studies are presented for the transmission loss in the 0–100kHz frequency range of a 1cm thick composite material slab containing oblate spheroidal inclusions of varying aspect ratios when the slab is submerged under water. The results are compared with the case of an isotropic composite material having identical constituent material properties and volume fractions.
Measurements of tortuosity in stereolithographical bone replicas using audiofrequency pulses
Authors: Attenborough Keith , Shin Ho-Chul , Qin Qin , Fagan Michael J , Langton Christian M
Published: October 2005

The tortuosity of five air-filled stereolithographical cancellous bone replicas has been obtained from measurements using audiofrequency pulses in a rectangular waveguide. The data obtained from the replicas yields information about anisotropy with respect to orthogonal axes of the passages that would be marrow filled in vivo. A strong relationship has been found between the acoustically measured tortuosity and the independently measured porosity. Use of stereolithographical bone replicas has the potential to simulate perforation and thinning of cancellous bone and hence evaluate the dependence of acoustic properties on cancellous bone microstructure. As an “extreme” illustration of such use, “inverses” of the original replicas have been manufactured and acoustic measurements have been made on them. The data reveal significantly greater tortuosity of the passages that are geometrically equivalent to the original solid bone structures.
Coupling of flexural and longitudinal wave motion in a periodic structure with asymmetrically arranged transverse beams
Authors: Friis Lars , Ohlrich Mogens
Published: October 2005

In this paper we investigate the coupling of flexural and longitudinal wave motions in a waveguide with structural side branches attached at regular intervals. The analysis is based on periodic structure theory, and considers wave transmission in a fully tricoupled and semidefinite periodic assembly of beam-type elements (or plane-wave transmission for normal incidence in a similar plate assembly). Receptances of a composite periodic element with offset resonant beams are derived and used for computing the frequency-dependent propagation constants of three coupled wave types as well as the distribution of motion displacements in each wave type. This is used for calculating the spatial variation of the forced harmonic responses of a semi-infinite periodic structure to point excitations by a longitudinal force and by a moment. Numerical simulations reveal the complicated wave coupling phenomena, which are clarified by calculating the ratio of flexural and longitudinal kinetic energies in the wave-carrying component for each wave type. In contrast to a corresponding, but uncoupled, system with significant broadband attenuation of flexural waves, the numerical results further show that the flexural-longitudinal wave coupling in a system with resonant side branches results in a highly enhanced wave transmission with very little attenuation from element to element.
Flat-walled multilayered anechoic linings: Optimization and application
Authors: Xu Jingfeng , Buchholz Jörg M. , Fricke Fergus R.
Published: October 2005

The concept of flat-walled multilayered absorbent linings for anechoic rooms was proposed three decades ago. Flat-walled linings have the advantage of being less complicated and, hence, less costly to manufacture and install than the individual units such as wedges. However, there are difficulties in optimizing the design of such absorbent linings. In the present work, the design of a flat-walled multilayered anechoic lining that targeted a 250 Hz cut-off frequency and a 300 mm maximum lining thickness was first optimized using an evolutionary algorithm. Sixteen of the most commonly used commercial fibrous building insulation materials available in Australia were investigated and fourteen design options (i.e., material combinations) were found by the evolutionary algorithm. These options were then evaluated in accordance with their costs and measured acoustic absorption performances. Finally, the completed anechoic room, where the optimized design was applied, was qualified and the results showed that a large percentage (75%–85%) of the distance between the sound source and the room boundaries, on the traverses made, were anechoic.
Phonation thresholds as a function of laryngeal size in a two-mass model of the vocal folds
Authors: Lucero Jorge C. , Koenig Laura L.
Published: October 2005

This letter analyzes the oscillation onset-offset conditions of the vocal folds as a function of laryngeal size. A version of the two-mass model of the vocal folds is used, coupled to a two-tube approximation of the vocal tract in configuration for the vowel ∕a∕. The standard male configurations of the laryngeal and vocal tract models are used as reference, and their dimensions are scaled using a single factor. Simulations of the vocal fold oscillation and oral output are produced for varying values of the scaling factor. The results show that the oscillation threshold conditions become more restricted for smaller laryngeal sizes, such as those appropriate for females and children.
Precedence-based speech segregation in a virtual auditory environment
Authors: Brungart Douglas S. , Simpson Brian D. , Freyman Richard L.
Published: October 2005

When a masking sound is spatially separated from a target speech signal, substantial releases from masking typically occur both for speech and noise maskers. However, when a delayed copy of the masker is also presented at the location of the target speech (a condition that has been referred to as the front target, right-front masker or F-RF configuration), the advantages of spatial separation vanish for noise maskers but remain substantial for speech maskers. This effect has been attributed to precedence, which introduces an apparent spatial separation between the target and masker in the F-RF configuration that helps the listener to segregate the target from a masking voice but not from a masking noise. In this study, virtual synthesis techniques were used to examine variations of the F-RF configuration in an attempt to more fully understand the stimulus parameters that influence the release from masking obtained in that condition. The results show that the release from speech-on-speech masking caused by the addition of the delayed copy of the masker is robust across a wide variety of source locations, masker locations, and masker delay values. This suggests that the speech unmasking that occurs in the F-RF configuration is not dependent on any single perceptual cue and may indicate that F-RF speech segregation is only partially based on the apparent left-right location of the RF masker.
Informational masking of speech in children: Effects of ipsilateral and contralateral distracters
Authors: Wightman Frederic L. , Kistler Doris J.
Published: October 2005

Using a closed-set speech recognition paradigm thought to be heavily influenced by informational masking, auditory selective attention was measured in 38 children (ages 4–16years) and 8 adults (ages 20–30years). The task required attention to a monaural target speech message that was presented with a time-synchronized distracter message in the same ear. In some conditions a second distracter message or a speech-shaped noise was presented to the other ear. Compared to adults, children required higher target∕distracter ratios to reach comparable performance levels, reflecting more informational masking in these listeners. Informational masking in most conditions was confirmed by the fact that a large proportion of the errors made by the listeners were contained in the distracter message(s). There was a monotonic age effect, such that even the children in the oldest age group (13.6–16years) demonstrated poorer performance than adults. For both children and adults, presentation of an additional distracter in the contralateral ear significantly reduced performance, even when the distracter messages were produced by a talker of different sex than the target talker. The results are consistent with earlier reports from pure-tone masking studies that informational masking effects are much larger in children than in adults.
Near field acoustic holography with particle velocity transducers
Authors: Jacobsen Finn , Liu Yang
Published: October 2005

Near field acoustic holography is usually based on measurement of the pressure. This paper describes an investigation of an alternative technique that involves measuring the normal component of the acoustic particle velocity. A simulation study shows that there is no appreciable difference between the quality of predictions of the pressure based on knowledge of the pressure in the measurement plane and predictions of the particle velocity based on knowledge of the particle velocity in the measurement plane. However, when the particle velocity is predicted close to the source on the basis of the pressure measured in a plane further away, high spatial frequency components corresponding to evanescent modes are not only amplified by the distance but also by the wave number ratio (kz∕k). By contrast, when the pressure is predicted close to the source on the basis of the particle velocity measured in a plane further away, high spatial frequency components are reduced by the reciprocal wave number ratio (k∕kz). For the same reason holography based on the particle velocity is less sensitive to transducer mismatch than the conventional technique based on the pressure. These findings are confirmed by an experimental investigation made with a p-u sound intensity probe produced by Microflown.
Reflection and time-reversal of ultrasonic waves in the vicinity of the Rayleigh angle at a fluid-solid interface
Authors: Vignon François , Marquet Fabrice , Cassereau Didier , Fink Mathias , Aubry Jean-François , Gouedard Pierre
Published: October 2005

When sending a plane ultrasonic wave toward a fluid-solid interface, the reflected wave is affected, depending on the incident angle. Around the Rayleigh angle the reflection coefficient has a strong and rapidly varying imaginary part. This has the effect of distorting the reflected wave front. If this reflected wave is time-reversed and sent back toward the interface, the reflected wave of this time-reversed wave should not present any distortion, as the time-reversal process restores the original phases. A theoretical and experimental study of these phenomena has been done. The distortion of the reflected waves around the Rayleigh angle is observed and as expected this distortion is canceled by the time-reversal process. However a significant loss of energy in the time-reversed signal is observed for incident angles around the Rayleigh angle, as part of the energy contained in the Rayleigh wave escapes the time-reversal mirror and is lost for the time-reversal process. In a second part, it is shown by simulations and experiments how this signal distortion by reflection around Rayleigh angle influences spatial focusing of waves by time-reversal or simple time-delay methods.
ANTENNA IMPEDANCE MATCHING WITH NEURAL NETWORKS
Authors: HEMMINGER THOMAS L.
Published: October 2005

Impedance matching between transmission lines and antennas is an important and fundamental concept in electromagnetic theory. One definition of antenna impedance is the resistance and reactance seen at the antenna terminals or the ratio of electric to magnetic fields at the input. The primary intent of this paper is real-time compensation for changes in the driving point impedance of an antenna due to frequency deviations. In general, the driving point impedance of an antenna or antenna array is computed by numerical methods such as the method of moments or similar techniques. Some configurations do lend themselves to analytical solutions, which will be the primary focus of this work. This paper employs a neural control system to match antenna feed lines to two common antennas during frequency sweeps. In practice, impedance matching is performed off-line with Smith charts or relatively complex formulas but they rarely perform optimally over a large bandwidth. There have been very few attempts to compensate for matching errors while the transmission system is in operation and most techniques have been targeted to a relatively small range of frequencies. The approach proposed here employs three small neural networks to perform real-time impedance matching over a broad range of frequencies during transmitter operation. Double stub tuners are being explored in this paper but the approach can certainly be applied to other methodologies. The ultimate purpose of this work is the development of an inexpensive microcontroller-based system.
SUBJECT MATCHING: A CASE STUDY ON TWO-SIDED MATCHING
Authors: XING XIAOLIN , LIU YUNHUA
Published: October 2005

This paper investigates subject matching in the National University of Singapore (NUS). The matching process is conducted in a primary market and a secondary market. In the primary market, students and departments are matched by a centralized matching procedure, based on their submitted preferences. Students who are not satisfied with their allocations in the primary market can choose to join the secondary market. By comparing matching results in these two markets, we show how a centralized matching procedure and a decentralized matching procedure can work together to produce a desirable outcome, especially in a many-to-many matching market.
THE BUDGET DEFICIT AND ECONOMIC PERFORMANCE: A SURVEY
Authors: SALEH ALI SALMAN , HARVIE CHARLES
Published: October 2005

The relationship between budget deficits and macroeconomic variables (such as growth, interest rates, trade deficit, exchange rate, among others) represents one of the most widely debated topics among economists and policy makers in both developed and developing countries. However, the purpose of this paper is to review the extensive literature to such a relationship, concentrating on theoretical debates and empirical studies, in order to derive substantive conclusions, which can be beneficial in the macroeconomics area; policy analysis; or in terms of constructing or developing a macroeconomic model for analyzing the impact of budget deficits on macroeconomic variables. The majority of these studies regress a macroeconomic variable on the deficit variable. These studies are cross-country and utilize time series data. In general the key outcomes from the studies presented in this paper indicated that both the method of financing and the components of government expenditures could have different effects. Therefore, it is crucial for the government to distinguish between consumption and investment expenditures especially when the government is in the process of evaluating the impact of fiscal policy on private investment and output growth or in the process of cutting expenditures to reduce the fiscal imbalances in the country. Even though the overall results from the empirical literature with respect to the impact of public investment on private investment and growth are ambiguous, the bulk of the empirical studies find a significantly negative effect of public consumption expenditure on growth, while the effects of public investment expenditure (such as on education, healthcare) are found to be positive although less robust. The key findings from these studies is important in particular for developing countries to be aware of the importance of government investment expenditures in the area of education, healthcare, infrastructure to long-term economic growth and the benefits from which are an important contributor to welfare and well-being. The key outcome from all of the studies presented in this paper while investigating the relationship between the budget deficit and current account deficit showed strong evidence in both developed and developing countries towards supporting the Keynesian proposition (conventional view) which suggests that an increase in the budget deficit would induce domestic absorption and, hence import expansion, causing a current account deficit. The key findings from the empirical studies investigating the relationship between the budget deficit and interest rates indicated strong evidence towards supporting the Keynesian model of a significant and positive relationship between budget deficits and interest rates. The major outcomes from the empirical studies examining the relationship between budget deficits and inflation showed strong evidence that the budget deficit financed through monetization and a rising money supply could lead to inflation.
FOREIGN DIRECT INVESTMENT AND ECONOMIC GROWTH IN MALAYSIA: THE ROLE OF DOMESTIC FINANCIAL SECTOR
Authors: CHOONG CHEE-KEONG , YUSOP ZULKORNAIN , SOO SIEW-CHOO
Published: October 2005

This study aims to incorporate the role of domestic financial system in transferring the technological diffusion embodied in FDI inflows on the Malaysian economy from 1970–2001. Applying bound test, or unrestricted error correction model (UECM) proposed by Pesaran et al. (2001), the presence of FDI inflows creates a positive technological diffusion in both short- and long-run if the evolution of domestic financial system has achieved a certain minimum level. This implies that the improvement of technology level in Malaysia in the long run is due to the spillover efficiency effects from FDI. Hence, the study suggests that FDI tends to be more likely to enhance economic growth more efficiently when a recipient country has a well-developed and well-functioning financial sector.
PERTURBED SELF-SIMILAR MASSLESS SCALAR FIELD IN THE SPACE–TIMES WITH CIRCULAR SYMMETRY IN (2+1)-GRAVITY
Authors: CHAN R. , DA SILVA M. F. A. , VILLAS DA ROCHA JAIME F.
Published: October 2005

We present in this work the study of the linear perturbations of the (2+1)-dimensional circularly symmetric solution, obtained in a previous work, with kinematic self-similarity of the second kind. We have obtained an exact solution for the perturbation equations and the possible perturbation modes. We have shown that the background solution is a stable solution.
ROLE OF PRESSURE IN QUASI-SPHERICAL GRAVITATIONAL COLLAPSE
Authors: CHAKRABORTY SUBENOY , CHAKRABORTY SANJUKTA , DEBNATH UJJAL
Published: October 2005

We study quasi-spherical Szekeres space–time (which possess no killing vectors) for perfect fluid, matter with tangential stress only and matter with anisotropic pressure respectively. In the first two cases cosmological solutions have been obtained and their asymptotic behavior have been examined while for anisotropic pressure, gravitational collapse has been studied and the role of the pressure has been discussed.
TEST OF PATCH COSMOLOGY WITH WMAP
Authors: KIM KYONG HEE , MYUNG YUN SOO
Published: October 2005

We calculate the power spectrum, spectral index, and running spectral index for inflationary patch cosmology arisen from Gauss–Bonnet braneworld scenario using the Mukhanov equation. This patch cosmology consists of Gauss–Bonnet (GB), Randall–Sundrum (RS-II), and four-dimensional (4D) cosmological models. There exist several modifications in higher order calculations. However, taking the power-law inflation by choosing different potentials depending on the model, there exist minor changes up to second order corrections. Since second order corrections are rather small in the slow-roll limit, we could not choose a desired power-law model which explains the WMAP data. Finally we discuss the reliability of high order calculations based on the Mukhanov equation by comparing the perturbed equation including 5D metric perturbations. It turns out that first order corrections are reliable, while second order corrections are not proved to be reliable.
TOWARDS A NEW APPROACH TO QUANTUM GRAVITY PHENOMENOLOGY
Authors: CORICHI ALEJANDRO , SUDARSKY DANIEL
Published: October 2005

The idea that quantum gravity manifestations would be associated with a violation of Lorentz invariance is very strongly bounded and faces serious theoretical challenges. This leads us to consider an alternative line of thought for such phenomenological search. We discuss the underlying viewpoint and briefly mention its possible connections with current theoretical ideas. We also outline the challenges that the experimental search of the effects would seem to face.
THE CHARACTERISTICS OF INNOVATION-INTENSIVE SMALL FIRMS: EVIDENCE FROM "NORTHERN BRITAIN"
Authors: FREEL MARK
Published: October 2005

Drawing upon data from a sample of 597 small manufacturing firms, the current paper hopes to contribute to the emerging body of empirical literature, which seeks to distinguish the characteristics of more and less innovative small firms. Importantly, in so doing, a definition of innovation is employed which, at least partially, resolves many of the difficulties associated with operationalising the relativity of "innovativeness" and which places the emphasis upon innovation as a commercial, rather than a technological, phenomenon. To this end, a number of noteworthy observations are apparent. In broad terms, the paper points to the limits of viewing innovation output as a simple function of the volume of inputs. In other words, capability appears to matter at least as much as capacity. Moreover, the findings place the means of improving innovativeness firmly within the ambit of executives and suggest that these are likely to involve internal strategising and the development of human and intellectual capital.
A COMPARATIVE ANALYSIS OF INNOVATION STRATEGY AND IMPLEMENTATION IN THE U.K.: THE EFFECTS OF PERIPHERALITY
Authors: HARRIS RICHARD I. D. , MCADAM RODNEY , REID RENEE S.
Published: October 2005

Although the U.K. has a common political system, there are distinct regional differences. These differences are reflected in the outcomes of U.K. Government attempts to devise and implement innovation strategy within all parts of the U.K. Northern Ireland's (NI) regional differences are increased by the province's peripheral location in relation to the rest of the U.K. The aim of this paper is to explore the outcomes of innovation strategy and implementation on an U.K. regional basis. Moreover, the paper seeks to examine the effects of location by comparing the NI results with the other U.K. regions. This paper's focus is on NI; however, the level of analysis is the U.K. This is extremely important as it provides comparative data in order to test whether or not NI does differ from other regions in terms of its level of innovation activity. Data from the Community Innovation Survey shows that NI has a significantly lower level of product innovation, together with the lowest level of novel product innovation and the lowest market share attributed to novel innovations compared to the rest of the U.K. In addition, NI has the fourth lowest level of process innovation (and the lowest level of novel process innovation) in the U.K. Overall, NI can be considered something of an outlier region with regard to product innovation.
DEVELOPING PROJECT COMPETENCE: EMPIRICAL REGULARITIES IN COMPETITIVE PROJECT OPERATIONS
Authors: SÖDERLUND JONAS
Published: October 2005

Projects play key roles in many modern industries and firms. The management of these economic systems, project management, is continuously developed and considered to be at the core of competitive advantage. Traditional research on project management has, however, paid scant attention to the capabilities needed for firms that depend on projects in their business operations. Furthermore, traditional work on the capabilities and competence of the firm pays limited attention to the specific traits of project processes. In the present paper, project competence is considered to be one of three strategic competencies frequently observed in modern firms. We develop an overall model for the analysis of project competence. The proposed model identifies four building blocks of project competence, namely project generation, project organising, project leadership and teamwork. In an empirical study we elaborate on some empirical regularities in the operations of firms that to a large extent depend on projects. The companies studied are ABB, Ericsson, Skanska and Posten. We illustrate the possibilities of this model and show some variations between the companies. The article illustrates how the project competence framework might explain the differences among the competitiveness of firms.
The Four Sources of Law in Zoroastrian and Islamic Jurisprudence
Authors: János Jany
Published: October 2005

It is "only our lack of familiarity with Sasanian law," von Grunebaum opined (1970: 37), "that prevents us from uncovering its traces in the fiqh". And Joseph Schacht argued that Sasanian law did have an influence on Islamic law. But neither Schacht nor any other modern scholar has provided persuasive evidence for such influence. In this article I argue that the influence of Sasanian legal theory on Islamic legal theory in the formative period was minimal, at best. It is true that, like Islamic law, Sasanian law was based on four sources: (1) The Awesta or holy book of the Zoroastrians; (2) oral law; (3) the consensus of the sages; and (4) the judicial practice of the courts (kardag). However, the possibility of Iranian influence on early Islamic jurisprudence is limited by historical, cultural, geographical and chronological factors, and the evidence of the sources suggests that Sasanian legal thinking was distinctive from that of the Sunni usulis.
Daytime Cycle of Low-Level Clouds and the Tropical Convective Boundary Layer in Southwestern Amazonia
Authors: Strong C. , Fuentes J. D. , Garstang M. , Betts A. K.
Published: October 2005

During the wet season in the southwestern Amazon region, daytime water transport out of the atmospheric mixed layer into the deeper atmosphere is shown to depend upon cloud amounts and types and synoptic-scale velocity fields. Interactions among clouds, convective conditions, and subcloud-layer properties were estimated for two dominant flow regimes observed during the 1999 Tropical Rainfall Measuring Mission component of the Brazilian Large-Scale Biosphere–Atmosphere (TRMM-LBA) field campaign. During daytime the cloud and subcloud layers were coupled by radiative, convective, and precipitation processes. The properties of cloud and subcloud layers varied according to the different convective influences of easterly versus westerly lower-tropospheric flows. The most pronounced flow-regime effects on composite cloud cycles occurred under persistent lower-tropospheric flows, which produced strong convective cloud growth with a near absence of low-level stratiform clouds, minimal cumulative attenuation of incoming solar irradiance (∼25%), rapid daytime mixed-layer growth (>100 m h−1), and boundary layer drying (0.22 g kg−1 h−1), high convective velocities (>1.5 m s−1), high surface buoyancy flux (>200 W m−2), and high latent heat flux (600 W m−2) into cloud layer. In contrast, persistent westerly flows were less convective, showing a strong morning presence of low-level stratiform genera (>0.9 cloud amount), greater cumulative attenuation of incoming solar irradiance (∼47%), slower mixed-layer growth (<50 m h−1) with a slight tendency for mixed-layer moistening, and a delayed peak in the low-level cumuliform cloud cycle (2000 versus 1700 UTC). The results reported in this article indicate that numerical models need to account for cloud amounts and types when estimating water vapor transport to the cloud layer.
Incorporation of CO2 Exchange Processes into a Multilayer Atmosphere–Soil–Vegetation Model
Authors: Nagai Haruyasu
Published: October 2005

Carbon dioxide (CO2) exchange processes were incorporated into a multilayer atmosphere–soil–vegetation model known as SOLVEG, and its performance was examined using measurements obtained from a grassland site. It was also applied for the CO2 budget calculation in the surface ecosystem. The characteristic feature of this model is that it is multilayered for the atmosphere, soil, and vegetation and includes sophisticated processes involving transmission of the solar and longwave radiation fluxes in the canopy. The model framework for the heat and water exchanges between the atmosphere and ground surface was validated by comparisons of ground surface heat fluxes between the calculated and observed values in the previous papers. In this study, a new model framework that includes the exchange process of CO2 along with those of heat, water, and momentum, which interact with each other, has been developed. The performance of the model was examined by comparing the calculated and observed values for surface fluxes of heat, water, and CO2. Because no measurements are available for the direct evaluation of the CO2 calculation in the soil, the calculation has been examined by drawing comparisons between the CO2 fluxes above the ground in the period lacking active vegetation. Vegetation parameters were tuned using measurements of 2 months, and the model satisfactorily simulated measured fluxes for the 8-month-long test period. Moreover, the CO2 budget in the surface ecosystem was examined using the model simulation. The result indicates the necessity of the incorporated CO2 process for the CO2 budget in the surface ecosystem.
Climatologically Aided Mapping of Daily Precipitation and Temperature
Authors: Hunter Richard D. , Meentemeyer Ross K.
Published: October 2005

Accurately mapped meteorological data are an essential component for hydrologic and ecological research conducted at broad scales. A simple yet effective method for mapping daily weather conditions across heterogeneous landscapes is described and assessed. Daily weather data recorded at point locations are integrated with long-term-average climate maps to reconstruct spatially explicit estimates of daily precipitation and temperature extrema. The method uses ordinary kriging to interpolate base station data spatially into fields of approximately 2-km grain size. The fields are subsequently adjusted by 30-yr-average climate maps [Parameter-Elevation Regression on Independent Slopes Model (PRISM)], which incorporate adiabatic lapse rates, orographic effects, coastal proximity, and other environmental factors. The accuracy assessment evaluated an interpolation-only approach and the new method by comparing predicted and observed values from an independent validation dataset. The results of the accuracy assessment are compared for a 24-yr period for California. For all three weather variables, mean absolute errors (MAE) of the climate-imprint method were considerably smaller than those of the interpolation-only approach. MAE for predicted daily precipitation was ±2.5 mm, with a bias of +0.01. MAE for predicted daily minimum and maximum temperatures were ±1.7° and ±2.0°C, respectively, with corresponding biases of −0.41° and −0.38°C. MAE differed seasonally for all three weather variables, but the method was stable despite variation in the number of base stations available for each day.