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The present work consists of a statistical study of the monaural (lateral-reflection fractions and level) and binaural acoustic parameters (inter-aural cross-correlation coefficients) that evaluate the amount of early and late lateral acoustic energy encountered in 9 performance halls in Andalusia (southern Spain). Hall volumes range between 6,163 m3 and 34,594 m3 and all enclosures are used for presentations of symphonic concerts and other music performances. The majority of these venues are located in provincial capitals of the community and often constitute the only premises in the city where symphonic concerts can be held. The acoustic parameters under study here were derived from impulse responses analyses using a sine-sweep signals which were generated and processed by WinMLS 2004 software in the octave- band frequency centred from 125 to 4 kHz, and all parameters were spectrally averaged according to the ISO 3382-1 standard. A comparison is presented of monaural experimental results as a function of source- receiver distance with the prediction of Barron’s revised theory for concert halls, and the analyses of the acoustic parameter results are carried out in terms of their respective just noticeable differences: at the many microphone positions for the two source positions on stage, for the spatial distribution of seats in the audience zone relative to the central axis (for left- and right-hand sides) of the rooms, and for the presence of the orchestra shell on stage. Results reveal that the orchestra shell propitiates a perceptible decrement in the values of the early lateral energy fraction and an increment in the late lateral level at the audience seats. In addition, a regression study reveals that the two kinds of measures of laterality, monaural and binaural, are correlated when the hall-average data is considered, but they remain uncorrelated when all individual positions are used. Likewise, the ranges of variation of the acoustic parameters found in these halls are narrower than those specified in the ISO 3382-1. The paper concludes with a discussion on the relationships of hall-average data of the five parameters with eight geometric and acoustic variables.

Cosmological textures are known from numerical experiments to isotropise as they collapse. This article studies general energy configurations having the same form of energy density as do textures. Straightforward arguments based on an extension of Derrick's theorem lead to the conclusion that textures isotropise because they lose energy in doing so. The energy fraction lost in isotropisation is calculated. Since it is possible that some of the energy lost by macroscopic textures could be radiated as gravitational waves, this fractional energy loss estimates the maximal energy fraction which could be produced as gravitational radiation during texture isotropisation.

The data on the growth of the average charged-hadron multiplicity in [ital p]([ital [bar p]])-[ital p] collisions from [radical][ital s] =5 to 900 GeV, and in [ital e][sup +][ital e[minus]] annihilation from 10 to 90 GeV, are described by the same slowly increasing power of [ital s]. The power approaches an asymptotic value of the order of 0.1 only at [radical][ital s] [similar to]1000 TeV. The ratio of the average multiplicity in [ital e][sup +][ital e[minus]] annihilation to that in [ital pp] collisions is nearly constant at 1.5; thus, the difference between these averages increases. A small but increasing energy fraction tends to be removed from particle production in the extreme fragmentation region; this sustains relatively increasing production of high multiplicities of soft particles.

This paper proposes an enhanced pattern discovery algorithm for data streams processing of sensor networks, in order to improve the performance of SPIRIT. The new algorithm adapts the optimized correction for tracking weights vectors, and the dynamic expanding in detecting the number of hidden variables. Simulation results show that compared to the original algorithm, the proposed algorithm can reduce the reconstruction error, increase the energy fraction of reconstruction, and decrease the number of hidden variables, so it extract the principal components and discover patterns among streams more efficiently.

The efficiency of fat and protein retention by Bos indicus and its cross-breds was estimated from data obtained in the literature to verify possible differences between these animals and Bos taurus. After estimating the efficiencies, a correction factor was used to discount the metabolizable energy fraction that was spent in the maintenance and support metabolism processes. The efficiencies were then estimated again, assuming that all the remaining energy would correspond to the metabolizable energy available for body mass retention. The correction value used was considered satisfactory to discount energetic losses for maintenance and support. The efficiency values of partial body fat and protein retention in Bos indicus and its cross-bred were very similar to values reported by other authors who researched Bos taurus exclusively. A eficiência com que animais zebuínos e seus cruzamentos transformam a energia metabolizável consumida em gordura e proteína corporal foi estimada a partir de informações obtidas na literatura no intuito de verificar se existem diferenças entre esses animais e os de raças europeias. Após a estimativa das eficiências, usou-se uma correção para descontar a porção da energia metabolizável gasta na manutenção da massa corporal e no metabolismo de suporte. Posteriormente à aplicação da correção, as eficiências foram estimadas novamente, partindo-se do pressuposto de que o montante de energia restante corresponderia à energia metabolizável utilizada para acúmulo de massa corporal. O valor de correção utilizado foi considerado suficiente para descontar as perdas energéticas para mantença e suporte. Os valores de eficiência de retenção parcial de gordura e proteína corporal em animais zebuínos e mestiços Europeu × Zebu são muito próximos dos encontrados por outros autores em pesquisas com animais exclusivamente europeus.

A world model to estimate the energy fraction supplied by nuclear power was developed. The world was divided into ten local regions, within each of which the interactions between economy, society, ...

Extensive acoustics computer simulations have been made using Odeon computer simulation software. In 24 rectangular rooms representing "shoe‐box" type concert halls with volumes of 8 000 m3, 12 000 m3 and 16 000 m3 from 300 to 850 measurements positions have been analysed. Only room averaged objective measures are considered here, in particular Clarity (C80), Strength (G) and Early Lateral Energy Fraction (LF80). Results from simulations have been compared with regression models created based on real hall measurements. In general, simulated results of C80 and G are found to be in good agreement with regression models. Divergences are found in LF80 behaviour; these have been associated with influence of proportions of rectangular halls. Updated formula for predicting of LF80 in rectangular halls has been proposed, which takes into the account both width and length of hall.

We present QCD predictions of the two-particle distribution of hadrons in quark and gluon jets at small values of the energy fraction x, including next-to-leading corrections, which are of relative order √αs. A positive correlation, largest when the particles have similar energies and increasing towards smaller x, is predicted.

We study the impact of a temperature-dependent curvaton decay rate on the primordial curvature perturbation generated in the curvaton scenario. Using the familiar sudden decay approximation, we obtain an analytical expression for the curvature perturbation after the decay of the curvaton. We then investigate numerically the evolution of the background and of the perturbations during the decay. We first show that the instantaneous transfer coefficient, related to the curvaton energy fraction at the decay, can be extended into a more general parameter, which depends on the net transfer of the curvaton energy into radiation energy or, equivalently, on the total entropy ratio after the complete curvaton decay. We then compute the curvature perturbation and compare this result with the sudden decay approximation prediction., 23 pages, 9 figures

Late lateral energy level (GLL) and lateral energy fraction (LF) are two room acoustics measures that have been shown to correlate with certain aspects of spatial impression in concert halls. The purpose of this study was to investigate the repeatability of GLL and LF measurements. A custom microphone stand was built that can be adjusted in each spatial dimension separately to allow for accurate and precise microphone placement. Room impulse responses (IRs) were measured at six receiver locations in a 2500-seat auditorium using two different methods to obtain the lateral energy IR: the beamformed dipole response from a spherical microphone array, and a studio-grade figure-of-eight microphone. Three sets of IR measurements were taken at each receiver location. In between sets, the microphone stand was removed and the various adjustment points were randomly repositioned. The stand was then replaced in the same position to re-measure the IRs. The variability between the measurements at each receiver location was found to be relatively low for GLL (the standard deviation ranged between 0.22 and 0.73 JNDs for the 125–1000 Hz sum), and higher for LF (the standard deviation ranged between 0.49 and 2.80 JNDs for the average over the 125–1000 Hz octave bands). [Work supported by NSF Grant 1302741.]

Several objective measures have been proposed to describe the feeling of spatial impression in concert halls, including Lateral Energy Fraction (LF) and Interaural Cross‐Correlation Coefficient (IACC). However, previous studies have shown that LF and IACC values did not highly correlate with each other at individual seat positions in real halls [J. S. Bradley, J. Acoust. Soc. Am. 96, 3525–3535 (1994)]. To investigate the listener envelopment aspect of spatial impression further, subjective paired‐comparison tests have been run using signals which have various values for LF, early IACC (from 5–80 ms), late IACC (from 80 ms–1 s), and late lateral relative sound level (GLL). Another proposed measure, called Interaural Level Fluctuations (IALF), has also been included, which is based on the rate of change over time of the level difference between the ears. The binaural test signals were generated by the room acoustics simulation program ODEON, using four different musical motifs, and were presented to test subjects via headphones. Results from the experiments are presented. [Work supported by ASA Hunt Postdoctoral Research Fellowship.]

We record ECGs from healthy human subjects during 24-h long intervals, using ambulatory equipment. We calculate from the data various parameters, searching for those that change in a clear and systematic way under a homoepathic stimulus, (Strophantus hispidus 30 c). The energy fraction at high frequencies in the power spectrum of heart rate variability fulfills this condition, and we are able to interpret our results in a way consistent with the information on this medicine in the homeopathic Materia Medica.

The measurement of the inelastic photoproduction of charmonium at HERA seems to have ignited a new charmonium crisis. The (already discredited) color singlet model fits the data for large charmonium energy fraction z, where the NRQCD model qualitatively fails. We here point out that by the straightforward inclusion of color singlet and octet processes in the soft color (color evaporation) scheme, the HERA data can be accommodated for all z. We anticipate that the color singlet model will fail at low z, as it does in hadroproduction., 10 pages, Revtex, uses epsfig.sty to include 4 postscript figures. Also available from the UW-Madison Phenomenology preprint archives at http://pheno.physics.wisc.edu/pub/preprints/1998/madph-98-1045.ps.Z or at ftp://pheno.physics.wisc.edu/pub/preprints/1998/madph-98-1045.ps.Z

In shallow water communication channel, acoustic interactions with sea surface and bottom interfaces cause the inter-symbol interference that hinders the efficient and reliable communication. In this case, signal-to-multipath ratio (SMR) rather than signal-to-noise ratio can be used as an indicator to describe the quality of the communication channel. However, it is difficult to estimate precisely the SMR from the measured communication data. In this talk, we propose the energy fraction of the channel impulse response existing within one symbol duration as an alternative to SMR. Communication experiment was conducted on the southern coast of Korea in waters 45 m deep in source-receiver ranges of 100 m to 1 km. The Bit-error-rate performance is compared to the energy fraction in one symbol duration. In addition, the correlation between the energy fraction in a symbol and SMR is investigated through a Monte Carlo simulation.

Designing a vineyard hall is generally considered as more challenging and time consuming than designing a shoebox hall. Acoustics design of a moderately large vineyard hall was investigated by computer simulation regarding both the audience and the performers. Alternative schemes with orthogonal and splayed terraces were developed with design strategies featuring seating arrangement, wall inclining, ceiling pitch, recess of remote side seating, wall splaying, riser slope, and railing arrangement. Low correlations among most acoustical measures indicated the potential for setting diverse design goals. Optimized schemes with a frontal terrace increased high-frequency components of a voice source by nearly 2 dB for the seats surrounding the stage while confined spatial decay of strength and sustained early decay were achieved. Lateral energy fraction was mainly determined by inclination and splaying of the terraces and side walls. Without significantly affecting energy distribution for the audience, layouts ...

Impulse response measurements and binaural recordings were taken in a 900-seat multi-purpose hall in three clusters of nine adjacent seats. Each cluster contained a central seat, the seats immediately to the left and to the right, and the three seats in the rows directly in front of and behind the central seat. Differences between the seats were analyzed in terms of the standard room measures and spatial measures lateral energy fraction (LF) and late lateral energy level (GLL). The typical JNDs were used to evaluate the differences between seat pairs within a given cluster. Differences on the order of 1 or more JNDs were found between most seat pairs within a cluster in most octave bands between 125 Hz to 4000 Hz for early decay time, clarity index, strength, and LF. In terms of GLL, the average difference between pairs of seats was 0.6 dB. However, a total of 14 pairs of seats had differences in GLL between 1.0 to 2.0 dB. A listening test was carried out to determine if subjects could hear differences in...

Chavin de Huantar is a monumental World Heritage archaeological site in the Peruvian highlands predating Inca society by over 2000 years. The importance of site acoustics is suggested by distinctive architectural features, notably an extensive network of underground galleries used in part for ritual purposes. The labyrinthine galleries are arranged in a series of small rectangular alcoves off narrow corridors. Here we focus on measuring and modeling the acoustics at Chavin to understand the implications of auditory experiences within the galleries as related to the site's role in developing religious authority. Acoustic measurements and models of a site can be used to archive site acoustics, estimate the acoustics of inaccessible or alternative site architectures, and reconstruct original site acoustics; they may also be used to corroborate aspects of rituals suggested by other archaeological data. Preliminary acoustic measurements at Chavin show a short reverberation time, dense and energetic early reflections, and a large lateral energy fraction. The short reverberation time would enable rhythmically articulated group performance using Strombus shell trumpets found onsite. The early reflections would provide strong acoustic reinforcement and consistent resonances for participants in gallery alcoves. The wide soundfield would envelop participants, contributing to the ritual experience.

The objective characterisation of the subjective listening effect of single number quantities are well known in concert halls such: reverberation time, clarity, centre time, lateral energy fraction and so on. The Bartok Bela Concert Hall in the Palace of Arts in Budapest has been inaugurated at 15th of March 2005. The acoustic consultant office of the hall was ARTEC Ltd. A set of objective measurements has been carried out in the Concert Hall and a series of listening tests were accomplished. Results of the experiment show clear correlations in the relationship of architectural and room acoustical parameters. Apart from the important conclusions, there are some questions revealed.

This study will involve a controlled experiment to determine the correlation between hearing comfort and lateral energy fraction (LEF). (Hearing comfort has also been described as ease of hearing, and is a measure of speech intelligibility.) LEF is dependent on the geometry of surfaces near the source. Therefore, in order to study the effect of the angle of reflective walls near a speech source on hearing comfort, rooms with identical reverberation time, noise level, and volume are modeled. The angle between walls near the speaker is the only physical variable. The RT in every room will be 0.6 s and the background noise will be exactly NC 25. The angle between reflective walls on either side of the speaker will be changed in 5° increments. The speaker is always located 3 ft. in front of the varying corner, and the listener is always located 15 ft. from source. This ensures that the signal to noise ratio can also be held constant. The data from this modeling experiment should explain the relationship between hearing comfort and room geometry, as measured by the lateral energy fraction.

Most of the objective measures which are currently used to quantify spatial impression in auditoria, such as lateral energy fraction (LF), interaural cross‐correlation coefficient (IACC) and late lateral relative sound level (GLL), are calculated from an impulse response. For subjective testing, these impulse responses are often later convolved with music recorded in an anechoic environment to simulate music performance in the hall. One spatial impression measure, though, interaural level fluctuations (IALFs) which was first proposed by Griesinger [Aud. Eng. Soc., Preprint No. 3292 (1992)] and further developed by L. M. Wang and A. C. Gade [J. Acoust. Soc. Am. 107, 2891(A) (2000)], is calculated from the musical source signal instead of from the impulse response. Preliminary investigations showed that the IALF, calculated from simulated sound fields generated by ODEON, changed relatively the same for different pieces of music across various halls. If IALF is a valid measure for spatial impression, then this indicates that the musical source is not critical in evaluating the difference in spatial impression between halls. In this paper, results from subjective listening tests are presented to determine if the same trend is perceived by listeners across different musical motifs, which would aid in validating IALF.

A coherent set of subjective experiments (published in 1973 and 1981) established the effect of spatial impression associated with early lateral reflections. The early lateral energy fraction was proposed as an objective measure. Some authors have preferred to use measures linked to cross correlation, presumably on the basis that this is probably closer to the mechanism used by the ear. The paper reviews the results of measurements of the early lateral energy fraction in 17 British concert spaces, as well as considering the measured results by Bradley in 13 North American concert halls. The discussion considers the relationship between early lateral energy fraction and hall width, the behavior of the measure close to the source and in both parallel‐sided halls and fan‐shaped halls. The design requirements for high spatial impression are also considered. The subjective effect of early lateral reflections is also influenced by sound level. The consequences for design of considering this additional variable in combination with the directional distribution will also be discussed. Spatial impression in concert halls and opera houses will be examined.

Most physical variables other than RT are known to vary significantly within a concert hall. Namely, early to late energy ratio, lateral energy fraction, and sound strength. Less well known are the subjective correlates to the above variations. A series of experiments were carried out in order to assess the number and meaning of subjective dimensions throughout a single hall. Testing environments were both an anechoic chamber array and an actual hall with artificial sources, where subjects were asked to judge classical music samples. In both cases the standard spatial distribution was modified by the addition of discrete reflections while keeping level and RT constant. At least four subjective dimensions were found, as many as found in hall‐to‐hall comparisons. Up to 59% of variance was related to the spatial image of the source. After comparing results between the anechoic chamber and the actual hall, the visual impression seems to partially compensate for the variations due to distance. These results ra...

In the early 1960s, Paul Veneklasen began to develop an idea to synthesize an indoor acoustical space coming to fruition with the development and construction of an electroacoustic system called Auditorium Synthesis. This system allows the listener to preview various types of spaces prior to construction [Paul S. Veneklasen, Int. Symposium on Arch. Acoustics, 21–43 (1974)]. Listener preferential settings including source strength (G), early decay time (EDT), early/late energy (C), and lateral energy fraction from the Otis A. Singletary Center for the Arts (Lexington, Kentucky). A comparison of preferred orchestral settings and modeled seat locations will be performed. With impulse response data from the completed concert hall at the Singletary Center for the Arts, a comparison will be shown of newer parameters between the modeled seat locations from Auditorium Synthesis and concert hall data.

Acoustic parameters (including reverberation time, early decay time, relative sound level, early to late sound ratios, lateral energy fraction, and interaural cross correlation) have been measured in Boettcher Concert Hall. All parameters were measured using different settings of variable architectural features such as acoustic drapes, variable height overhead stage reflectors, and movable stage towers. The monaural parameters were also measured with and without an audience. The effects of the variable features on the acoustic parameters are assessed. The effects of the audience on some of the acoustic parameters have been estimated using standard calculation methods. Calculated differences are compared to those actually measured in the hall. [Work supported by the Concert Hall Research Group.]

The object of this study is to make clear the relation between the shape of balcony and acoustical properties under the overhang, and to derive a design criterion for balcony configuration in auditoria. On the assumption that a physical change of the sound field caused by building a balcony would be primarily a reduction of the energy of early reflections from upside, directional characteristics of early reflections were measured in auditoria both with and without a balcony, and the subjective effect of reflections arriving from upside on auditory envelopment was psycho‐ acoustically examined. First, the results of measurement showed that the ratio of the vertical component to total early reflection energy ERV was very small under the overhang. That is a peculiarity of the sound field under the balcony. Next, the results of a series of psychoacoustical experiments showed that auditory envelopment became weaker as ERV decreased when lateral energy fraction was constant. They suggested that the lack of earl...

The new metabolisable protein system (AFRC, 1992) introduces the requirement to distinguish between the energy in feeds which is fermentable (available for microbial growth) and that which is non-fermentable (available to the host animal; NFE). Fermented forages such as grass silage (GS) may contain substantial amounts of fermentation acids (FA) (volatile fatty acids (VFA) and lactic acid (LA)) and therefore, contain a considerable proportion of NFE. The aim of the present experiment was to investigate the use of near infrared reflectance spectroscopy (NIRS) as a rapid method for predicting the FAs in fresh (undried) GS.

A pair of heavy leptons with a mass of 1.8 GeV can explain the step- function-like behavior of the charge-particle energy fraction in e$sup +$e$sup -$ annihilation except for the resonance region around 4.1 GeV. The preliminary result of the e-$mu$ events reported by Perl, in particular the effects of spin alignment, are discussed in terms of this heavy lepton. We comment on a possible way to distinguish the heavy lepton from heavy hadrons. (AIP)

We discuss a general way in which QCD can be checked in lepton-induced reactions — even with low statistics data. This is the “angular energy flow”, or the average energy fraction outside a cone of opening angle 2σ about the principal jet axis. in the final state of deep inelastic reactions. We illustrate this method by a perturbative calculation of the angular energy flow in e+e−→qq¯g→ jets. This perturbative approach can be extended to other deep inelastic reactions wit h gluon jets. At high enough energy, it should test QCD beyond lowest order in αs.

We consider three broad classes of nonstandard models for b quark decay: (1) b → llq with charged or neutral leptons of arbitrary flavor; (2) b → l q q ; and (3) b → qa − where a − is a Higgs boson or hyperpion. For these classes of models we have calculated the charged energy fraction and the inclusive yields of electrons, muons, protons, and lambdas. We demonstrate that these model predictions are inconsistent with CLEO measurements at the γ (4S).

Since the possible importance of early lateral reflections for good concert hall acoustics was first proposed in 1967, a substantial body of evidence from many involved in the field has accumulated to support this claim. An extensive series of experiments was conducted with a simulation system to investigate the determinants of the subjective effect created by early lateral reflections, which is called here “spatial impression”. The effects of reflection delay, direction, level and spectrum were tested. The results lead to an objective measure, the early lateral energy fraction, which is linearly related to the subjectively perceived spatial impression.

A relation for calculating the energy fraction fu/f in open systems has been analyzed from the viewpoint of the precise determination of the length of nondeformed sample Lo and its temperature dependence. An iterative method has been proposed for determining the fu/f and thermal coefficient of volume expansion βs and Lo. Various methods for determining fu/f of dry samples have been applied to open systems. Eine Beziehung zur Berechnung der rel. Energie-Komponente fu/f in offenen Systemen wurde unter dem Gesichtspunkt der exakten Bestimmung der Lange Lo der nicht-deformierten Probe und ihrer Temperaturabhangigkeit analysiert. Es wird ein Iterativ-Verfahren zur Bestimmung von fu/f, des thermischen Volumenausdehnungskoeffizienten βs und der Lange Lo vorgeschlagen. Verschiedene Methoden zur Bestimmung von fu/f von trockenen Proben wurden auf offene Systeme angewendet.

The DTA method has been applied for the investigation of the metastable II → IV transition in ND4NO3. This transition which differs from the usual one in NH4NO3, was found to occur in two steps, with the consequent observation of a double peak in the differential temperature curve. The difference between the two steps varied between about 1.9 and 0.2°C, depending on thermal cycling and on annealing. When the number of heating—cooling cycles was raised from 1 to about 60, the energy fraction W1/(W1 + W2) increased from 0.22 to 0.28, and after that remained constant. Energies W1 and W2 above represent the high and low temperature steps of the transition, respectively. When the number of heating—cooling cycles exceeded 47, a supercooling effect was observed in the low temperature step of the transition, but not in the high temperature step.

The fraction of the total available energy carried by photons and the fraction carried by neutral particles of all types ine + e − multihadron final states have been measured at three centre-of-mass energies between 12 and 35 GeV. These fractions are approximately 27% and 37% with no strong dependence on centre-of-mass energy and the event topology. The neutrino energy fraction is estimated to be less than 10% at the 95% confidence level.

So far, permanent confinement of quarks is a purely phenomenological principle, not yet derived from quantum chromodynamics (QCD). A phenomenological model is exhibited that has confinement as well as the usual asymptotically-free short-distance behavior of QCD, and a crude approximation is made to the so-called energy-momentum sum rule of deep inelastic lepton-proton scattering, yielding about 0.65 as the quark energy fraction at |k 2 | ⋍ 3−4 GeV 2 .

The fraction of final states consisting of two jets plus a massive lepton-pair is calculated exactly to first order in QCD. It is shown that the description in terms of opening angle 2δ of the jet and energy fraction 1-e inside the jet is different from the corresponding situation ine + e −.

The energy transferred to neutral π mesons in the interaction of nuclear-active particles with the lead nucleus was studied with an ionization calorimeter. The mean value of the energy transferred to π0 mesons is [Formula: see text]. The [Formula: see text] distribution is also presented.

Data on μ+μ− and μ−e+ events from the CERN-Dortmund-Heidelberg-Saclay and Columbia-BNL neutrino experiments, respectively, are employed to determine the fragmentation function for charmed quarks. It is found that the data are all well described by a flat fragmentation function D(z) (where z is the energy fraction taken by the charmed meson), in agreement with the expectation from bremsstrahlung-type models. The data definitely exclude a behaviour ∼exp(−3z), typical of uncharmed hadrons, suggested by a previous phenomenological analysis. They also discriminate against the possibility that the fragmentation function is concentrated at large z, as predicted by fireball-type models.

Computer model applications for aquifer thermal energy storage (ATES) systems along with modelling methodology are described. The base case system employing just groundwater as heat source for a heat pump would be sufficient to provide nearly one half of the yearly heat load in a community heating system in a strict northern climate. The non-purchased energy fraction can still be increased by 15–25 per cent by interseasonal storage of heat injected in the summertime from a low grade heat source, e.g. lake surface waters or simple solar collector designs.

A study of B meson decays into DlX final states is presented. In these events, neutral and charged D mesons originate predominantly from B+ and B0 decays, respectively. The dilution of this correlation due to D** production has been taken into account. From 263 700 hadronic Z0 decays collected in 1991 with the DELPHI detector at the LEP collider, 92 D0→K-π+, 35 D+→K-π+π+ and 61 D*0→D0π+ followed by D0→K-π+ or D0→K-π+π+π -, are found with an associated lepton of the same charge as the kaon. From the D0l- and D*+l-, the probability fd that a b quark hadronizes into a B- (or {Mathematical expression}) meson is found to be 0.44 ±0.08±0.09, corresponding to a total (Bs+Λb) hadronization fraction of 0.12-0.12+0.24. By reconstructing the energy of each B meson, the b quark fragmentation is directly measured for the first time. The mean value of the B meson energy fraction is: {Mathematical expression} Reconstructing D-lepton vertices, the following B lifetimes are measured: {Mathematical expression} and an average τ(B)=1.23-0.13+0.14(stat.)±0.15(syst.) ps is found. Allowing for decays into {Mathematical expression}, the B+ and B0 lifetimes are: {Mathematical expression} © 1993 Springer-Verlag.

Room acoustical parameters have frequently been used to evaluate or predict the acoustical performance in rooms. For housing complexes in urban areas with high population density, it is important to improve acoustic performance not solely indoors, but outdoors as well; for example on the balconies or in the yards. This paper investigates to what extent classic room acoustical parameters would be able to predict the perceived acoustic comfort in outdoor spaces (i.e., courtyards) of virtual housing complexes. Individual and combined effects of a series of independent variables (such as facade absorption, sound source, and observer position) on short-term acoustic comfort were investigated in three laboratory experiments. ODEON software was used for virtual inner yard simulation, whereby 2D spatialization was carried out for a playback over five loudspeakers. Moderate facade absorption was found to increase acoustic comfort. Relatively pleasant and relatively unpleasant sounds were associated with comfort and discomfort, respectively. Lower acoustic comfort ratings were observed at receiver positions with high sound pressure levels and/or strong flutter echoes. A further analysis of the results is carried out here with respect to the room acoustical parameters and their ability to predict the acoustic comfort ratings. Speech transmission index (STI), definition (D50), clarity of speech (C50) and music (C80), early decay time (EDT), and lateral energy fraction (LF80) were found to be significantly correlated with acoustic comfort. They were found to be significant predictors of acoustic comfort in a series of linear mixed-effect models. Furthermore, linear mixed-effect models were established with the A-weighted equivalent continuous sound level, LAeq, as a significant predictor of acoustic comfort.