Miracle-dz/UniFAR-FTUs huggingface dataset:
Desenvolvimento de um Sistema de Visão para Inspeção Automática de Tecidos

A number of defects can arise in the processes of spinning and weaving of textile industry. The identification of defective tissues in the early stages of the process reduces waste and discards. The objective of this work is to develop a system for automated inspection of fabrics. Statistical techniques based on intensity discontinuities on images of tissue are used to perform the detection of defective regions. The achieved results have shown the effectiveness of the employed approach for detecting different types of defects. Keywords-automated inspection; computer vision; segmentation; textile Resumo—Uma série de defeitos podem surgir nos processos de fiação e tecelagem da indústria têxtil. A identificação de tecidos defeituosos nas etapas iniciais do processo reduz desperdı́cios e devoluções. O objetivo do presente trabalho é desenvolver um sistema de inspeção automatizada de tecidos. Técnicas estatı́sticas de processamento baseadas na descontinuidade de intensidade das imagens dos tecidos são utilizadas para realizar a detecção de regiões defeituosas. Os resultados alcançados têm demonstrado a efetividade da abordagem proposta na identificação de diferentes tipos de defeito. Keywords-inspeção automatizada; segmentação; tecido; visão computacional
Enhancing the Open‐Circuit Voltage of Perovskite Solar Cells by up to 120 mV Using π‐Extended Phosphoniumfluorene Electrolytes as Hole Blocking Layers

Four π‐extended phosphoniumfluorene electrolytes (π‐PFEs) are introduced as hole‐blocking layers (HBL) in inverted architecture planar perovskite solar cells with the structure of ITO/PEDOT:PSS/MAPbI3/PCBM/HBL/Ag. The deep‐lying highest occupied molecular orbital energy level of the π‐PFEs effectively blocks holes, decreasing contact recombination. It is demonstrated that the incorporation of π‐PFEs introduces a dipole moment at the PCBM/Ag interface, resulting in significant enhancement of the built‐in potential of the device. This enhancement results in an increase in the open‐circuit voltage of the device by up to 120 mV, when compared to the commonly used bathocuproine HBL. The results are confirmed both experimentally and by numerical simulation. This work demonstrates that interfacial engineering of the transport layer/contact interface by small molecule electrolytes is a promising route to suppress nonradiative recombination in perovskite devices and compensates for a nonideal energetic alignment at the hole‐transport layer/perovskite interface.
An assessment of danger during spring floods and ice jams in the north of European Russia

Abstract. Heavy ice jams during spring floods are common on rivers in the northern European Russia. Climate changes of the last decades have caused significant changes in the ice regime of rivers. Continuous freezing periods, followed by sludge ice jams and late freezing at high water levels, occur with increasing frequency. Winter break-ups have become more frequent. The most recent catastrophic flood in the area under study took place in the spring of 2013. The probability of floods and ice jamming is evaluated; the duration and depth of inundation at various water levels are calculated with an assessment of the accompanying economic losses in the Northern Russia.
Learning to Ask Unanswerable Questions for Machine Reading Comprehension

Machine reading comprehension with unanswerable questions is a challenging task. In this work, we propose a data augmentation technique by automatically generating relevant unanswerable questions according to an answerable question paired with its corresponding paragraph that contains the answer. We introduce a pair-to-sequence model for unanswerable question generation, which effectively captures the interactions between the question and the paragraph. We also present a way to construct training data for our question generation models by leveraging the existing reading comprehension dataset. Experimental results show that the pair-to-sequence model performs consistently better compared with the sequence-to-sequence baseline. We further use the automatically generated unanswerable questions as a means of data augmentation on the SQuAD 2.0 dataset, yielding 1.9 absolute F1 improvement with BERT-base model and 1.7 absolute F1 improvement with BERT-large model.
Interest rate risk of Australian REITS: A panel analysis

Australian REITs adopt either internal or external property management structures. The sector’s returns have been rewarding until the Global Financial Crisis, when rising costs of debt and years of aggressive borrowing eroded REIT values. Externally managed trusts had relatively higher levels of debt than internally managed counterparts, thus increasing the sensitivities to interest rate risks. Yet internally managed REITs engage in a wider set of operating activities which compound market and financial risks. This study uses panel and panel quantile regressions to examine the joint impact of financial leverage and management structure on REIT returns in terms of their sensitivities towards the stock market and changes to interest rates from 1980 to 2013 and how these vary at different parts of an economic cycle. It is found that the impact of market returns is greater for internally managed REITs and those with more debt. REITs are only negatively affected by changes to short-term interest rates at the lowest 5% quantile of returns. Changes to long-term interest rates have an adverse effect on REITs only at the upper 75% and 95% quantiles. The possibilities that rental yields and inflationary expectations may offset the influences of financing costs are considered. Internal management appears to compound the effects of the stock market and interest rates on REIT returns. This has implications for investors looking to select REITs as substitutes for direct property investments.
Computer Usage and Perceptions among Accounting Students: A Survey in a Public University

Satu kajian telah dijalankan ke atas 288 orang pelajar jurusan perakaunan di Universiti Malaya untuk mengenal pasti arah aliran penggunaan komputer di kalangan bakal graduan perakaunan. Kajian ini yang menerangkan tahap penggunaan komputer pada masa kini di kalangan pelajar perakaunan di dalam negeri dan juga tanggapan mereka ke atas komputer dapat memberikan gambaran sama ada aka un tan yang dilahirkan nanti mempunyai kemah iran teknologi maklumat dan komunikasi (lCT) seperti dikehendaki oleh majikan. Kemahiran ini dapat membantu mereka menghadapi cabaran mencari pekerjaan dan juga bersaing dengan graduan luar negara. Malaysia yang sedang menuju ke arah ekonomi yang berasaskan pengetahuan (K-economy) memerlukan generasi yang celik lCT. Kajian ini menggambarkan kesediaan para bakal graduan merealisasikan cabaran tersebut dan juga menunjukkan sama ada usaha Kerajaan dapat memenuhi matlamat keseluruhan agenda pendidikan dan teknologi maklumat negara.
Distributed Optimization for Over-Parameterized Learning

Distributed optimization often consists of two updating phases: local optimization and inter-node communication. Conventional approaches require working nodes to communicate with the server every one or few iterations to guarantee convergence. In this paper, we establish a completely different conclusion that each node can perform an arbitrary number of local optimization steps before communication. Moreover, we show that the more local updating can reduce the overall communication, even for an infinity number of steps where each node is free to update its local model to near-optimality before exchanging information. The extra assumption we make is that the optimal sets of local loss functions have a non-empty intersection, which is inspired by the over-paramterization phenomenon in large-scale optimization and deep learning. Our theoretical findings are confirmed by both distributed convex optimization and deep learning experiments.
Effects of Spatial Transformer Location on Segmentation Performance of a Dense Transformer Network

Semantic segmentation solves the task of labelling every pixel inan image with its class label, and remains an important unsolvedproblem. While significant work has gone into using deep learningto solve this problem, almost all the existing research uses methodsthat do not make modifications on spatial context considered for thepixel being labelled. Spatial information is an important cue in taskssuch as segmentation, reusing the same spatial span for every pixeland every label may not be the best approach. Spatial TransformerNetworks have shown promising results in improving classificationperformance of existing networks by allowing networks to activelymanipulate their input data to achieve better performance. Our workshows the benefit of incorporating Spatial Transformer Networksand their corresponding decoders into networks tailored to semanticsegmentation. Our experiments show an improvement in performanceover baseline networks when using networks augmentedwith Spatial Transformers.
Simulation of Fresnel based beam focusing and steering for a crossed electrode array

Fresnel based beamforming has been investigated for use with a high frequency crossed electrode array. A Fresnel zone plate uses a pattern of in phase and phase reversed pulses across the aperture chosen based on the distance from the element to the focus. The pattern of positive and negative pulses can be achieved using an array material whose response depends on a DC bias (e.g. electrostrictive ceramics, CMUTs) and applying either a positive or negative voltage. Fresnel based focusing introduces a challenge in pulsed ultrasound applications. The delays are quantized to 0 or ? /2, therefore, the pulses do not properly overlap when the difference in element-focus distance exceeds a wavelength. Because of this, the bandwidth is reduced below an acceptable standard for pulsed imaging. We have developed a novel design that pulses separate sub-apertures of the array while compensating for the delay error in each section. In exchange, the number of transmit events increases. A Fresnel approach is advantageous for a crossed electrode array using the following scheme. The Fresnel aperture focuses in azimuth on transmit while the elevational elements are beamformed traditionally. Between transmit and receive events the signals switch sides. The biases are applied in elevation and dynamic receive beamforming can be completed in azimuth and a two-way focus is achieved. A 40MHz crossed electrode array with 64 elevational and 64 azimuthal elements was simulated using Field II software. The results were compared with a 64x64 element traditionally beamformed 2D array. The two-way radiation patterns from the crossed electrode array using the Fresnel approach show -6dB beamwidths comparable to the 4096 element array but requires only 128 array connections. The resolution was 102, 126 and 151 µm when steered to 0, 15 and 25 degrees respectively. The side lobe levels raised by 15dB using the Fresnel approach.
Does training benefit those who do not get any? Elasticities of complementarity and factor price in South Africa

Commentators claim that a shortage of skills in South Africa is constraining output and that a rise in skill supply would benefit less skilled occupations. This assumes or implies skilled and unskilled labour are complements. Hicks Elasticities of Complementarity and elasticities of factor price are estimated between capital and five occupations. The results show that skilled/artisanal and unskilled labour are complements while semi-skilled and unskilled labour are substitutes. These results allow for imperfectly elastic product demand, rigid wages and inference on highly non-linear elasticities. Aggregated estimates suggest More skilled labour complements Less skilled labour.
Pseudo-LiDAR++: Accurate Depth for 3D Object Detection in Autonomous Driving

Detecting objects such as cars and pedestrians in 3D plays an indispensable role in autonomous driving. Existing approaches largely rely on expensive LiDAR sensors for accurate depth information. While recently pseudo-LiDAR has been introduced as a promising alternative, at a much lower cost based solely on stereo images, there is still a notable performance gap. In this paper we provide substantial advances to the pseudo-LiDAR framework through improvements in stereo depth estimation. Concretely, we adapt the stereo network architecture and loss function to be more aligned with accurate depth estimation of faraway objects --- currently the primary weakness of pseudo-LiDAR. Further, we explore the idea to leverage cheaper but extremely sparse LiDAR sensors, which alone provide insufficient information for 3D detection, to de-bias our depth estimation. We propose a depth-propagation algorithm, guided by the initial depth estimates, to diffuse these few exact measurements across the entire depth map. We show on the KITTI object detection benchmark that our combined approach yields substantial improvements in depth estimation and stereo-based 3D object detection --- outperforming the previous state-of-the-art detection accuracy for faraway objects by 40%. Our code is available at this https URL.
The Regional distribution of Knowledge-Intensive Services in Europe : a spatial approach

There is a rich debate in the innovation literature about to what extent innovation has become an international (or globalised) phenomenon, or, on the contrary, it maintains its local/regional character. As Koschatzky (2001) notes, given the fact that knowledge is commonly tied to personal capabilities; it has a clear geographical component. In the case of knowledge-intensive services (KIS) most of analyses come to the same conclusion: distance is particularly relevant when knowledge (mainly of a tacit type) is diffused. Starting from this premise, a burgeoning literature on the contribution of knowledge-intensive business services (KIBS) to regional innovation has emerged. Most of these papers adopt a national perspective, that is, analyse regions in a specific country. On the contrary, comparisons of regional features have been carried out in very few papers: Germany and the UK (Simmie and Strambach, 2006) or Germany and France (Muller and Zenker, 2001) are two examples. The objective of this paper is to take a step further and examine the distribution of knowledge-intensive services (KIS) in the European regions. For so doing we employ the data provided by the Regional Innovation Scoreboard (RIS) 2009. This database provides information on the innovation performance across 194 regions of the European Union and Norway. The methodology employed is known as spatial analysis and evaluates whether there are clusters in the location of KIS in the European regions, which involves three processes. First, to evaluate the existence of spatial autocorrelation by means of global statistics; the Moran’s I and the Geary’s C. Once verified the existence of positive spatial autocorrelation, it is possible to identify “clusters” of regions with high and low participations of KIS by using a local indicator of spatial autocorrelation (LISA). Finally, employing an econometric model, some potential explanatory factors for the concentration of KIS are examined. The results obtained support the hypothesis that KIS are spatially concentrated and confirm that spatial clusters are different in northern/central and southern/eastern regions. Moreover, a close relationship between location of KIS and regional innovation performance is found.
Evaluation of Vertical Coherence Length, Twist and Microstrain of GaAs / Si Epilayers Using Modified Williamson-Hall Analysis

Modified Williamson-Hall (WH) analysis is used to determine the reliable values of the microstructures for Zincblende epilayers grown on non-polar substrates. Systematic high resolution X-ray diffraction (HRXRD) experiments are performed for several skew symmetric reflections which enable an accurate measurement of the values of vertical coherence length (VCL) and microstrain of GaAs epilayers grown on Si. Furthermore, a simple method based on the orientation of Burgers vector is proposed for estimating the ratio of tilt and twist. In this method, the twist can be found easily once tilt is known. It is rather quick and the measured values of twist are very similar to those which are otherwise estimated by acquiring numerous HRXRD scans along with tedious fitting procedures. Presence of 60 mixed dislocations is confirmed from the cross sectional high resolution transmission electron microscope images of GaAs / Si samples. Furthermore, the estimated value of VCL is equivalent to the layer thickness measured by the surface profiler.
Comparison of hydrostatic and dynamical masses of distant X-ray luminous galaxy clusters

The main goal of this work is to compare the results of three dynamical mass estimators to the X-ray hydrostatic values, focussing on massive galaxy clusters at intermediate redshifts $z\sim0.3$. We estimated dynamical masses with the virial theorem, the Jeans equation, and the caustic method using wide-field VIMOS spectroscopy. We investigated the role of colour selection and the impact of substructures on the dynamical estimators. The Jeans and caustic methods give consistent results, whereas the virial theorem leads to masses $\sim15\%$ larger. The Jeans, caustic, and virial masses are respectively $\sim20\%$, $\sim30\%$, and $\sim50\%$ larger than the hydrostatic values. Large scatters of $\gtrsim50\%$ are mainly due to the two outliers RXCJ0014 and RXCJ1347; excluding the latter increases the mass ratios by $\sim10\%$, giving a fractional mass bias significant at $\gtrsim2\sigma$. We found a correlation between the dynamical-to-hydrostatic mass ratio and two substructure indicators, suggesting a bias in the dynamical measurements. The velocity dispersions of blue galaxies are $\sim15\%$ ($\sim25\%$ after removing the substructures) larger than that of the red-sequence galaxies; using the latter leads to dynamical masses $\sim10\%-15\%$ smaller. Discarding the galaxies part of substructures reduces the masses by $\sim15\%$; the effect is larger for the more massive clusters, owing to a higher level of substructures. After the substructure analysis, the dynamical masses are in perfect agreement with the hydrostatic values and the scatters around the mean ratios are divided by $\sim2$.
From National to Sub-National? Exploring the Territorial Dimension of Social Assistance in Italy

Abstract In countries that have experienced decentralisation processes, the role that central and sub-national authorities play in the governance of some social policies may vary considerably across regions. In Italy, for instance, whereas some regions (and municipalities) have been very active in financing social assistance programmes, others still overwhelmingly rely on resources directly allocated by the central government. This indicates that, in a ‘regionalised’ system, the development of a sub-national social dimension is not a territorially homogeneous phenomenon. Interestingly, cross-regional variation is mainly explained by differences in the strength of regionalist parties. The share of total social assistance spending allocated by sub-national authorities has increased significantly in those areas of the country where regionalist parties are stronger and does not seem to depend on ideological shifts on the left-right spectrum. Surprisingly, the positive effect of regional economic development on sub-national spending is not as strong as expected. On the other hand, female employment and population ageing seem to explain part of territorial divergence, the former having a positive effect and the latter a negative one on the dependent variable.
Factors Affecting Credit Risk in Indonesian Islamic Banks

This study uses dynamic panel data methods to examine the factors affecting credit risk in Indonesian Islamic banks. The panel data is collected from 11 full-fledged Islamic banks and 22 Islamic business units (windows) in conventional banks from 2004-2012, taking into account both macroeconomic variables and bank-specific variables. The Generalized Method of Moments (GMM), as proposed by Arellano and Bond (1991), is utilized to estimate the model. The results show that the GDP growth rate and the unemployment rate with a one-year lag have a strong effect on the level of the non-performing financing. Moreover, bank-specific variables such as bank’s diversification and financing structure have a positive effect on the problem financing although its direction is not as expected. It is hoped that the findings could draw attention to factors affecting credit risk in Islamic banks so that credit risk can be properly managed.
The effect of language complexity and group size on knowledge construction: Implications for online learning

This study investigated the effect of language complexity and group size on knowledge construction in two online debates. Knowledge construction was assessed using Gunawardena et al.’s Interaction Analysis Model (1997). Language complexity was determined by dividing the number of unique words by total words. It refers to the lexical variation. The results showed that knowledge construction and group size are significantly and negatively correlated. Also, the study revealed that knowledge construction and language complexity are significantly and positively correlated. Furthermore, the study demonstrated that language complexity is a significant predictor of knowledge construction in online debates. Some actions should be undertaken to increase language complexity in order to foster knowledge construction in online debates.
OBLIQUE PHOTOGRAMMETRY SUPPORTING 3D URBAN RECONSTRUCTION OF COMPLEX SCENARIOS

Abstract. Accurate 3D city models represent an important source of geospatial information to support various “smart city” applications, such as space management, energy assessment, 3D cartography, noise and pollution mapping as well as disaster management. Even though remarkable progress has been made in recent years, there are still many open issues, especially when it comes to the 3D modelling of complex urban scenarios like historical and densely-built city centres featuring narrow streets and non-conventional building shapes. Most approaches introduce strong building priors/constraints on symmetry and roof typology that penalize urban environments having high variations of roof shapes. Furthermore, although oblique photogrammetry is rapidly maturing, the use of slanted views for facade reconstruction is not completely included in the reconstruction pipeline of state-of-the-art software. This paper aims to investigate state-of-the-art methods for 3D building modelling in complex urban scenarios with the support of oblique airborne images. A reconstruction approach based on roof primitives fitting is tested. Oblique imagery is then exploited to support the manual editing of the generated building models. At the same time, mobile mapping data are collected at cm resolution and then integrated with the aerial ones. All approaches are tested on the historical city centre of Bergamo (Italy).
Verification of Multidimensional and Transient CFD Solutions

This work addresses the verification of multidimensional and transient numerical solutions based on Richardson extrapolation techniques. Alternative extrapolation strategies based on both simultaneous (SCR) and independent (ICR) space-and-time coordinates refinement studies are investigated. Extrapolation strategies studied encompass the generalized Richardson extrapolation (GRE) based on both the local and the global observed order of accuracy, and the mixed-order Richardson extrapolation (MORE). Performance of all verification methods investigated has been tested on a manufactured solution and on the flows in different piston–cylinder configurations. Results reveal that the global observed order of accuracy and the postprocessing estimators obtained from ICR studies can provide useful information on which the most suitable verification methods can be selected.