Miracle-dz/UniFAR-FTUs huggingface dataset:
Applications of large empirical spatio-temporal covariance matrix in multipath channels detection

This paper addresses the detection of a single signal in a multipath propagation channel using a sensors array in the case where the number of sensors M and the number of observations N are large and of the same order of magnitude and where the number of paths P is much smaller than M and N. In contrast with the single path context, the GLRT test cannot be implemented, and we evaluate the behaviour of tests based on the largest eigenvalues of the empirical spatio-temporal covariance matrix. Using a technical result showing that the largest singular values of low rank deterministic pertubation of certain Gaussian block-Hankel large random matrices behave as if the entries of the latter random matrices were independent identically distributed, we obtain a clear understanding of the advantages of the use of the spatial-temporal covariance matrix.
Plant stanol ester consumption and arterial elasticity and endothelial function†

We evaluated whether plant stanol esters mixed with different vegetable oil spreads improved arterial health. A total of 200 adults with serum cholesterol >5 mmol/l were randomised to consume camelina, rapeseed or sunflower oil spread with stanol (2 g/d) ester or sunflower oil spread without stanol ester (controls) for 3 months. Non-invasive ultrasound was used to measure carotid artery compliance (CAC) and brachial artery flow-mediated endothelial dependent vasodilatation (FMD) at baseline and after the intervention as markers of arterial health. Plant stanol esters reduced LDL-cholesterol by 9 % compared with controls (P < 0·001) similarly in the different treatment groups. In the combined treatment groups (n 147), CAC or FMD were not changed from controls (n 47). In a subgroup analysis, division of subjects at baseline into below and over sex-specific 50th percentiles of CAC and FMD revealed that low CAC was improved from 1·23 to 1·59 % per 10 mmHg in the treatment group (n 69), and from 1·42 to 1·47 % per 10 mmHg in controls (n 25), (P = 0·0035 between groups). Low FMD was improved from 6·9 % to 8·6 % in the treatment group (n 73) and from 6·6 % to 6·8 % in controls (n 24) (P = 0·05 between groups). In the respective high-median groups, CAC and FMD were not changed in spite of significantly lowered LDL-cholesterol. In conclusion, consumption of plant stanol ester for 3 months had no overall significant effect on arterial elasticity and endothelial function. A controlled study is needed to test whether beneficial changes are obtained in subjects with initially reduced arterial elasticity and endothelial function.
Internet Tools and Environments for Distance Education

This paper describes collaborative Internet environments for distance education. The Internet offers various possibilities for asynchronous as well as synchronous collaboration. This paper focuses on synchronous platforms which range from systems for shared applications to video conference systems. Beside platforms which are designed for research purposes ( Habanero, Groupkit and Share-Kit), two commercial products are examined: Netscape Conference and CUSeeMe. In addition to these platforms, a development of the University of Hagen is introduced: DreamTeam. The DreamTeam platform addresses the special needs of distance education environments. It comprises a development environment, a runtime environment and a simulation environment; it is based upon the concept of a de-centralised architecture. It minimises the development cycle for co-operative applications and encourages rapid prototyping. It is planned to use the DreamTeam environment for software courses and electronic lectures in the Virtual University project. The DreamTeam project is heavily supported by the project VirtUE a Virtual University for Europe, TEN-TELECOM contract 45493 * .
The association of right coronary artery conus branch size and course with ST segment elevation of right precordial leads and clinical outcome of acute anterior myocardial infarction

Introduction: Coronary artery disease is the leading cause of death worldwide and electrocardiogram (ECG) is a reliable diagnostic tool to determine a myocardial infarction. The present study tried to compare the relationship between the ECG findings and angiographic findings in patients with acute anterior myocardial infarction. Methods: Seventy-four patients with acute anterior ST elevation myocardial infarction (Ant- STEMI) presenting to the emergency room in the first 12 hours after the onset of symptoms were studied. Upon admission, a full 14-lead ECG (including leads V3R and V4R) were performed. Angiographic and ECG findings, as well as clinical outcome were compared between two groups. The statistical tests including Chi-square and independent t-test were used for data analysis. Results: Small conus branch was seen in 52 (70.3%) and large conus in 22 ( 29.7%) patients. STE in right-sided leads and heart failure were significantly higher in small conus branch group versus large conus branch (88.6% vs 11.4%, P < 0.001 and 34.6% vs 9.1%, P = 0.02 respectively). There was no significant difference in mortality rate between the two groups (5.8% in small conous group vs 0% in large conus group, P = 0.55). There was a significant difference in major adverse cardiac events (MACE) between the two groups (51.9% in small conous group vs 18.2% in large conus group, P = 0.01). Conclusion: In patients with anterior MI, small conus branch was associated with higher rate of major adverse cardiac events mostly because of increased rate of acute heart failure.
3D Beamforming for Spectral Coexistence of Satellite and Terrestrial Networks

Satellite communication (SatCom) is facing a spectrum scarcity problem due to the limited available exclusive spectrum and the high demand of the broadband satellite services. In this context, there has been an increasing interest in the satellite community to exploit the non- exclusive Ka-band spectrum in order to enhance the spectral efficiency of future broadband satellite systems. Herein, we propose a novel concept of enabling the spectral coexistence of satellite and terrestrial networks using three dimensional (3D) beamforming, which exploits the elevation dimension in addition to the commonly used azimuth dimension. The proposed beamforming solution is employed in a Multiple-Input Low Noise Block Downconverter (MLNB) based Feed Array Reflector (FAR) in contrast to the widely used Uniform Linear Array (ULA) structure. Within the employed antenna structure, the performance of the proposed beamforming solution is evaluated considering different feed arrangements. Finally, a database-assisted approach and two blind approaches are suggested for the effective implementation of the proposed solutions.
HE 0437–5439: An Unbound Hypervelocity Main-Sequence B-Type Star

We report the discovery of a 16th magnitude star, HE 0437-5439, with a heliocentric radial velocity of +723 ± 3 km s-1. A quantitative spectral analysis of high-resolution optical spectra obtained with the VLT and UVES shows that HE 0437-5439 is a main-sequence B-type star with Teff = 20,350 K, log g = 3.77, a solar (within a factor of a few) helium abundance and metal content, and rotating at v sin i = 54 km s-1. Using appropriate evolutionary tracks, we derive a mass of 8 M☉ and a corresponding distance of 61 kpc. Its Galactic rest-frame velocity is at least 563 km s-1, almost twice the local Galactic escape velocity, indicating that the star is unbound to the Galaxy. Numerical kinematical experiments are carried out to constrain its place of birth. It has been suggested that such hypervelocity stars can be formed by the tidal disruption of a binary through interaction with the supermassive black hole at the Galactic center (GC). HE 0437-5439 needs about 100 Myr to travel from the GC to its present position, much longer than its main-sequence lifetime of 25 Myr. This can only be reconciled if HE 0437-5439 is a blue straggler star. In this case, the predicted proper motion is so small that it can only be measured by future space missions. Since the star is much closer to the Large Magellanic Cloud (LMC; 18 kpc) than to the GC, it can reach its position from the center of the LMC. The proper motion predicted in this case is about 2 mas yr-1 (relative to the LMC), large enough to be measurable with conventional techniques from the ground. The LMC origin could also be tested by a high-precision abundance analysis.
Optimal spline-based RRT path planning using probabilistic map

This paper presents an optimal path planning algorithm that adopts the rapidly-exploring random tree(RRT) as a path planner. The RRT generates a valid path quickly, but it does not have the ability to control the quality of the path. In this paper, the nonholonomic path planning and the optimal path planning are tackled simultaneously within the RRT framework. The spline-based RRT algorithm generates a feasible path satisfying the differential constraints, and the RRT* strategy is incorporated to guarantee the optimal solution. In addition, the probabilistic map combining 3D Lidar and visual camera is used as a map for the path planning. Simulation results show that the proposed spline-based RRT* outputs a dynamically feasible optimal path.
Constraining Primordial Non-Gaussianity with the Abundance of High-Redshift Clusters

We show how observations of the evolution of the galaxy cluster number abundance can be used to constrain primordial non-Gaussianity in the universe. We carry out a maximum likelihood analysis incorporating a number of current data sets and accounting for a wide range of sources of systematic error. Under the assumption of Gaussianity, the current data prefer a universe with matter density Ωm ≃ 0.3 and are inconsistent with Ωm = 1 at the 2 σ level. If we assume Ωm = 1, the predicted degree of cluster evolution is consistent with the data for non-Gaussian models where the primordial fluctuations have at least twice as many peaks of height 3 σ or more as a Gaussian distribution does. These results are robust to almost all sources of systematic error considered: in particular, the Ωm = 1 Gaussian case can only be reconciled with the data if a number of systematic effects conspire to modify the analysis in the right direction. Given an independent measurement of Ωm, the techniques described here represent a powerful tool with which to constrain non-Gaussianity in the primordial universe, independent of specific details of the non-Gaussian physics. We discuss the prospects and strategies for improving the constraints with future observations.
Advanced face recognition system using Fourier Optics and Neural Networks

Conventional pattern recognition uses wavelet method which can identify facial pattern but it is restricted to recognition of unmasked and fully exposed faces. Added this process is more time consuming. To overcome these limitations this system is designed in the light of Fourier Optics and Neural Networks. The system uses an advanced optical Fourier plane correlator for (real time) face recognition and feature extraction. Photographs are captured in real time and are applied as input to the system, which are compared with images from database in near light speed by the Fourier plane correlator. Applications include Airport security, Rail road security, Security at Malls and other places where people congregate together.
Oracle-based Training for Phrase-based Statistical Machine Translation

A Statistical Machine Translation (SMT) system generates an n-best list of candidate translations for each sentence. A model error occurs if the most probable translation (1-best) generated by the SMT decoder is not the most accurate as measured by its similarity to the human reference translation(s) (an oracle). In this paper we investigate the parametric differences between the 1-best and the oracle translation and attempt to try and close this gap by proposing two rescoring strategies to push the oracle up the n-best list. We observe modest improvements in METEOR scores over the baseline SMT system trained on French– English Europarl corpora. We present a detailed analysis of the oracle rankings to determine the source of model errors, which in turn has the potential to improve overall system performance.
Full functional verification of linked data structures

We present the first verification of full functional correctness for a range of linked data structure implementations, including mutable lists, trees, graphs, and hash tables. Specifically, we present the use of the Jahob verification system to verify formal specifications, written in classical higher-order logic, that completely capture the desired behavior of the Java data structure implementations (with the exception of properties involving execution time and/or memory consumption). Given that the desired correctness properties include intractable constructs such as quantifiers, transitive closure, and lambda abstraction, it is a challenge to successfully prove the generated verification conditions. Our Jahob verification system uses integrated reasoning to split each verification condition into a conjunction of simpler subformulas, then apply a diverse collection of specialized decision procedures, first-order theorem provers, and, in the worst case, interactive theorem provers to prove each subformula. Techniques such as replacing complex subformulas with stronger but simpler alternatives, exploiting structure inherently present in the verification conditions, and, when necessary, inserting verified lemmas and proof hints into the imperative source code make it possible to seamlessly integrate all of the specialized decision procedures and theorem provers into a single powerful integrated reasoning system. By appropriately applying multiple proof techniques to discharge different subformulas, this reasoning system can effectively prove the complex and challenging verification conditions that arise in this context.
Sonic-Point and Spin-Resonance Model of the Kilohertz QPO Pairs

KHz QPOs have now been detected in more than twenty accreting neutron stars in low-mass binary systems. Two kHz QPOs are usually detected in each star. Burst oscillations and two kHz QPOs have recently been detected in the 401 Hz accretion-powered X-ray pulsar SAX J1808.4-3658. In this star the frequency of the burst oscillation is approximately equal to the star's spin frequency nu_spin whereas the frequency separation of the two kHz QPOs is approximately nu_spin/2. If as expected the frequency of the burst oscillations in other stars is also approximately nu_spin, the frequency separation is approximately nu_spin in some stars but approximately nu_spin/2 in others. A frequency separation approximately equal to nu_spin/2 is unexplained in all existing models of the kHz QPOs. Here we propose a modified version of the sonic-point beat-frequency model that can explain within a single framework why the frequency separation is close to nu_spin in some stars but close to nu_spin/2 in others. As in the original sonic-point model, the frequency nu_QPO2 of the upper kHz QPO is close to the orbital frequency nu_orb at the radius r_{sp} of the sonic point in the disk flow. We show that magnetic and radiation fields rotating with the star will preferentially excite vertical motions in the disk at the "spin-resonance'' radius r_{sr} where nu_orb - nu_spin is equal to the vertical epicyclic frequency, producing vertical motions in the disk that modulate the X-ray flux at approximately nu_QPO2 - nu_spin or approximately nu_QPO2 - nu_spin/2, depending on whether the disk flow at r_{sr} is smooth or clumped. This sonic-point and spin-resonance model can also explain quantitatively the decrease of the kHz QPO frequency separation with increasing accretion rate that is observed in many sources.
Vision-based SLAM using natural features in indoor environments

This paper presents a practical approach to solve the simultaneous localization and mapping (SLAM) problem for autonomous mobile platforms by using natural visual landmarks obtained from an stereoscopic camera. It is an attempt to depart from traditional sensors such as laser rangefinders in order to gain the many benefits of nature-inspired information-rich 3D vision sensors. Whilst this makes the system fully observable in that the sensor provide enough information (range and bearing) to compute the full 2D estate of the observed landmarks from a single position, it is also true that depth information is difficult to rely on, particularly on measurements beyond a few meters (in fact the full 3D estate is observable, but here robot motion is constrained to 2D and only the 2D problem is considered). The work presented here is an attempt to overcome such a drawback by tackling the problem from a partially measurable SLAM perspective in that only landmark bearing from one of the cameras is employed in the fusion estimation. Range information estimates from the stereo pair is only used during map building in the landmark initialization phase in order to provide a reasonably accurate initial estimate. An additional benefit of the approach presented here lies in the data association aspect of SLAM. The availability of powerful feature extraction algorithms from the vision community, such as SIFT, permits a more flexible SLAM implementation separated from feature representation, extraction and matching, essentially carrying out matching with minimal recourse to geometry.
Green Fluorescent Protein-based Expression Screening of Membrane Proteins in Escherichia coli

The production of recombinant membrane proteins for structural and functional studies remains technically challenging due to low levels of expression and the inherent instability of many membrane proteins once solubilized in detergents. A protocol is described that combines ligation independent cloning of membrane proteins as GFP fusions with expression in Escherichia coli detected by GFP fluorescence. This enables the construction and expression screening of multiple membrane protein/variants to identify candidates suitable for further investment of time and effort. The GFP reporter is used in a primary screen of expression by visualizing GFP fluorescence following SDS polyacrylamide gel electrophoresis (SDS-PAGE). Membrane proteins that show both a high expression level with minimum degradation as indicated by the absence of free GFP, are selected for a secondary screen. These constructs are scaled and a total membrane fraction prepared and solubilized in four different detergents. Following ultracentrifugation to remove detergent-insoluble material, lysates are analyzed by fluorescence detection size exclusion chromatography (FSEC). Monitoring the size exclusion profile by GFP fluorescence provides information about the mono-dispersity and integrity of the membrane proteins in different detergents. Protein: detergent combinations that elute with a symmetrical peak with little or no free GFP and minimum aggregation are candidates for subsequent purification. Using the above methodology, the heterologous expression in E. coli of SED (shape, elongation, division, and sporulation) proteins from 47 different species of bacteria was analyzed. These proteins typically have ten transmembrane domains and are essential for cell division. The results show that the production of the SEDs orthologues in E. coli was highly variable with respect to the expression levels and integrity of the GFP fusion proteins. The experiment identified a subset for further investigation.
Bispectrum speckle interferometry of IRC +10216: The dynamic evolution of the innermost circumstellar environment from 1995 to 2001

We present new near-infrared (JHK) bispectrum speckle-interferometry monitoring of the carbon star IRC+10216 obtained between 1999 and 2001 with the SAO 6 m telescope. The J-, H-, and K-band resolutions are 50 mas, 56 mas, and 73 mas, respectively. The total sequence of K-band observations covers now 8 epochs from 1995 to 2001 and shows the dynamic evolution of the inner dust shell. The present observations show that the appearance of the dust shell has considerably changed compared to the epochs of 1995 to 1998. Four main components within a 0: 2 radius can be identified in the K-band images. The apparent separation of the two initially brightest components A and B increased from191 mas in 1995 to351 mas in 2001. Simultaneously, component B has been fading and almost disappeared in 2000 whereas the initially faint components C and D became brighter (relative to peak intensity). The changes of the images can be related to changes of the optical depth caused, for instance, by mass-loss variations or new dust condensation in the wind. Our recent two-dimensional radiative transfer model of IRC+10216 suggests that the observed relative motion of components A and B is not consistent with the outflow of gas and dust at the well-known terminal wind velocity of 15 km s 1 . The apparent motion with a deprojected velocity of 19 km s 1 on average and of recently 27 km s 1 appears to be caused by a displacement of the dust density peak due to dust evaporation in the optically thicker and hotter environment. The present monitoring, covering more than 3 pulsation periods, shows that the structural variations are not related to the stellar pulsation cycle in a simple way. This is consistent with the predictions of hydrodynamical models that enhanced dust formation takes place on a timescale of several pulsation periods. The timescale of the fading of component B can well be explained by the formation of new dust in the circumstellar envelope.
Cognitive evoked potentials and central auditory processing in children with reading and writing disorders

Learning disorders are often magnified by auditory processing disorders (APD). Objective This paper aims to verify whether individuals with reading and writing disorders and P300 latencies above the average also present altered Staggered Spondaic Word (SSW) and speech-in-noise test results suggestive of APD. Materials and Methods This is a cross-sectional cohort study. Twenty-one individuals with reading and writing disorders aged between 7 and 14 years were enrolled. Results All subjects had normal findings on ENT examination, audiological tests, and brainstem auditory evoked potentials. The average P300 latency (334,25 ms) of all patients was picked as a cutoff point to divide the subjects into two groups: group A with latencies above 335 ms, and group B with latencies below 335 ms. Individuals in group A underwent SSW and speech-in-noise testing. Conclusion Altered results in the SSW and speech-in-noise tests suggestive of APD were found in the group of individuals with reading and writing disorders with P300 latencies above 335 ms.