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Determining the Particle Size of Debris from a Tunnel Boring Machine Through Photographic Analysis and Comparison Between Excavation Performance and Rock Mass Properties
No full textThis paper presents the results of a study carried out on a 6.3-m-diameter exploratory tunnel excavated in hard rock by an open tunnel boring machine (TBM). The study provides a methodology, based on photographic analysis, for the evaluation of the particle size distribution of debris produced by the TBM. A number of tests were carried out on the debris collected during the TBM advancement. In order to produce a parameter indicative of the particle size of the debris, the coarseness index (CI) was defined and compared with some parameters representative of the TBM performance [i.e. the excavation specific energy (SE) and field penetration index (FPI)] and rock mass features, such as RMR, GSI, uniaxial compression strength and joint spacing. The results obtained showed a clear trend between the CI and some TBM performance parameters, such as SE and FPI. On the contrary, due to the rock mass fracturing, a clear relationship between the CI and rock mass characteristics was not found
Dynamic inventory rationing: how to allocate stock according to managerial priorities. An empirical study
No full textMusic Mood Dataset Creation Based on Last.fm Tags
No full textMusic emotion recognition today is based on techniques that require high quality and large emotionally labeled sets of songs to train algorithms. Manual and professional annotations of songs are costly and hardly accomplished. There is a high need for datasets that are public, highly polarized, large in size and following popular emotion representation models. In this paper we present the steps we followed to create two such datasets using intelligence of last.fm community tags. In the first dataset, songs are categorized based on an emotion space of four clusters we adopted from literature observations. The second dataset discriminates between positive and negative songs only. We also observed that last.fm mood tags are biased towards positive emotions. This imbalance of tags was reflected in cluster sizes of the resulting datasets we obtained; they contain more positive songs than negative ones
Combined effect of noise and room acoustics on vocal effort in simulated classrooms
No full textThis work investigated the relationships between room acoustics, background noise level, and vocal effort of a speaker in simulated classrooms of various volumes. Under simulated acoustic environments, talkers adjusted their vocal effort linearly with the voice support, i.e., the degree of amplification offered by the room to the voice of a speaker, at his own ears. The slope of this relationship, called the room effect, of −0.24 dB/dB was significant only in the case of the highest noise levels of 62 dB. The vocal comfort for the speaker, however, was found to be more closely related to noise annoyance than to room reverberance
Vehicle Mass Estimation from CAN Data and Drivetrain Torque Observer
No full textA method for estimating the vehicle mass in real time is presented. Traditional mass estimation methods suffer due a lack of knowledge of the vehicle parameters, the road surface conditions and most importantly the effect of the vehicle transmission. To resolve these issues, a method independent of a vehicle model is utilized in conjunction with a drivetrain output torque observer to obtain the estimate of the vehicle mass. Simulations and experimental track tests indicate that the method is able to accurately estimate the vehicle mass with a relatively fast rate of convergence compared to traditional methods
Symmetric 10 Gbps PON operating with a single laser over 31 dB of ODN Loss
No full textWe propose a fully-bidirectional and symmetrical 10 Gbps OOK PON solution, using the same wavelength in both upstream and downstream directions. Thanks to the remodulation performed by the ONU, it is able to transport 20 Gbps per wavelength using only one optical source for the full network, regardless the number of users. The system is based on direct-detection in downstream and self-coherent detection in upstream, over a standard 31 dB loss splitter-based PON. We experimentally demonstrate the proposed architecture over a realistic PON fiber plant with one wavelength and commercial components. We then discuss the potential application of our solution in a ITU-T G.989 NG-PON2 PtP-WDM architecture
Curl-Constrained Gradient Estimation for Image Recovery from Highly Incomplete Spectral Data
No full textIn this paper, we introduce new gradient-based methods for image recovery from a small collection of spectral coefficients of the Fourier transform, which is of particular interest for several scanning technologies, such as magnetic resonance imaging. Since gradients of a medical image are much more sparse or compressible than the corresponding image, classical ℓ1-minimization methods have been used to recover these relative differences. The image values can then be obtained by integration algorithms imposing boundary constraints. Compared with classical gradient recovery methods, we propose two new techniques that improve reconstruction. First, we cast the gradient recovery problem as a compressed sensing problem taking into account that the curl of the gradient field should be zero. Second, inspired by the emerging field of signal processing on graphs, we formulate the gradient recovery problem as an inverse problem on graphs. Iteratively reweighted ℓ1 recovery methods are proposed to recover these relative differences and the structure of the similarity graph. Once the gradient field is estimated, the image is recovered from the compressed Fourier measurements using least squares estimation. Numerical experiments show that the proposed approach outperforms the state-of-the-art image recovery methods
Microstructural and Mechanical Characterization of Aluminum Matrix Composites Produced by Laser Powder Bed Fusion
No full textBeni culturali della Chiesa e vita ecclesiale negli anni del Concilio Vaticano II
No full textIl saggio ripercorre il rapporto tra il dibattito sul patrimonio culturale sviluppato negli anni della Commissione Franceschini e i concomitanti processi sociali e culturali innescati nel mondo ecclesiale dal Concilio Vaticano II; vengono analizzati i documenti relativi al patrimonio religioso inseriti nelle diverse parti dei lavori della Commissione, e in particolare viene approfondito il contributo che la Pontificia Commissione Centrale di Arte Sacra ha portato ai lavori della Commissione. In conclusione si ripercorrono alcuni passaggi istituzionali, normativi e culturali relativi al dibattito sui beni culturali di interesse religioso nell'ultimo quarto del Novecento
Predicting Peak Flows in Real Time through Event Based Hydrologic Modeling for a Trans-Boundary River Catchment
No full textInvestigating the hydrological response of an area to adverse climate changes and extreme rainfall events is crucial for managing land and water resources and mitigating the natural hazards like floods. Limited availability of the in situ data, especially in case of Transboundary Rivers, further highlights the need to develop and evaluate decision support systems which may predict the flows in real time using open source rainfall data. This paper presents the study conducted in Chenab River catchment, Pakistan, to develop and evaluate a hydrologic model using HEC-HMS for predicting flows based on TRMM rainfall data. The catchment was analyzed for hydro-morphological properties using SRTM DEM in HEC-GeoHMS. To rely on open source data as much as possible, digital soil map of the world developed by FAO and global land cover map developed by European Space Agency were utilized to compute Curve Number grid data for the catchment. These preliminary data analyses were employed to set initial values of different parameters to be used for model calibration. The model was calibrated for five rainfall events occurred in the rainy seasons of 2006, 2010 and 2013. The calibrated model was then validated for four other rainfall events of similar type in the same years. Consistency in simulated and observed flows was found with percent difference in volume ranging from −6.17 % to 5.47 % and percent difference in peak flows to be in the range of 6.96 % to 7.28 %. Values of Nash-Sutcliffe Efficiency were ranging from 0.299 to 0.909 with an average value of 0.586 for all flow events. The model was found well capable of capturing the hydrologic response of the catchment due to rainfall events and can be helpful in providing alerts of peak flows in real time based on real time/forecasted rainfall data