Miracle-dz/UniFAR-FTUs huggingface dataset:
A Taxonomy of Certificate Status Information Mechanisms

A number of mechanisms have been proposed for generating and disseminating information on the status of certificates. Their operation is different, if not contradicting sometimes, and advantages and disadvantages depend on the requirements of the underlying PKI. PKI designers and implementors should perform a small scale study before deploying such a mechanism in a specific PKI, in order to select the most suitable mechanism for their environment. This paper presents a method for categorising Certificate Status Information mechanisms, depending on their elementary functionality. This taxonomy can be used as a guide for selecting CSI mechanisms to be used in large-scale PKI deployment efforts.
Performance improvement in decentralized adaptive control: a modified model reference scheme

A new decentralized model reference adaptive controller is proposed for a continuous time large scale system composed of N interconnected linear subsystems with unknown parameters. In the case where the high frequency gains of the transfer functions of each of the isolated subsystems is known, the new scheme can be used to improve the band transient behavior that typically results from poor knowledge of the subsystem parameters. It is shown that the transient performance improvement has to be traded off against the size of the allowable unmodeled interconnections in such a way that as the unmodeled interconnections disappear, the improvement in transient performance can be made arbitrary. Since each local adaptive scheme uses approximate differentiators, the presence of high frequency sensor noise may impose additional limitations on the effectiveness of the new scheme. <<ETX>>
XUV Sources Based on Intra-Oscillator High Harmonic Generation With Thin-Disk Lasers: Current Status and Prospects

Ultrafast thin-disk laser (TDL) oscillators provide higher intracavity pulse energy, average power, and peak power levels than any other femtosecond laser oscillator technology. They are suitable for driving extreme nonlinear interactions directly inside the laser oscillator. High harmonic generation (HHG) driven inside ultrafast TDL oscillators is a very recent approach for the generation of coherent extreme ultraviolet (XUV) light at multi-megahertz repetition rates. In this paper, we review the current state of the development, discuss the technological potential, and give an outlook toward the future developments. We compare the current performance to established technologies and evaluate possible limitations. We discuss future improvements, such as reduction of the driving pulse duration and increase of the intracavity peak power, efficient extraction of the XUV light from the cavity, and carrier-envelope offset frequency stabilization of the generated XUV light. Due to the power scalability of the TDL concept and the possibility to operate in a spectrally broadened regime with pulse durations below the gain bandwidth limitation, intra-oscillator HHG with TDLs has a high potential for powerful table-top multi-megahertz coherent XUV light sources for science and applications.
Closed-Loop Identification for Model Predictive Control of HVAC Systems: From Input Design to Controller Synthesis

Heating, ventilation, and air conditioning (HVAC) systems are responsible for maintaining occupants’ thermal comfort and share a large portion of the overall building energy use. Hence, it is of great interest to improve the performance of HVAC control systems and thus the building energy efficiency. Model predictive control (MPC) has been proved to be a promising control strategy to be employed in this field. However, MPC implementation relies on the model of the system, and inaccurate models can deteriorate the control performance, while overly complicated models can lead to the prohibitive computational burden. Because of this, existing models do not usually allow the MPC controller to adjust multiple set points (e.g., both temperature and flow rates) and do not include the dynamics of the heating and ventilation subsystems with their local controllers. In this paper, we address the challenge of developing more reliable HVAC models for MPC controllers based on the experimental data. Data are obtained from an experiment designed using a graph theoretical technique, which guarantees maximum information content in the data. The resulting models are employed to design local controllers of the heating and ventilation subsystems, which are experimentally tested in a real HVAC test bed. A supervisory MPC controller that incorporates the closed-loop models of the heating and ventilation subsystems is then developed. This can lead to a control strategy able to more effectively adapt key HVAC set points based on weather conditions, occupancy, and actual thermal comfort, as shown by a numerical study based on the data from the HVAC test bed.
LTE Advanced: 3GPP Solution for IMT-Advanced

From the editors of the highly successful LTE for UMTS: Evolution to LTE-Advanced, this new book examines the main technical enhancements brought by LTE-Advanced, thoroughly covering 3GPP Release 10 specifications and the main items in Release 11. Using illustrations, graphs and real-life scenarios, the authors systematically lead readers through this cutting-edge topic to provide an outlook on existing technologies as well as possible future developments. The book is structured to follow the main technical areas that will be enhanced by the LTE-Advanced specifications. The main topics covered include: Carrier Aggregation; Multiantenna MIMO Transmission, Heterogeneous Networks; Coordinated Multipoint Transmission (CoMP); Relay nodes; 3GPP milestones and IMT-Advanced process in ITU-R; and LTE-Advanced Performance Evaluation. Key features: * Leading author and editor team bring their expertise to the next generation of LTE technology * Includes tables, figures and plots illustrating the concepts or simulation results, to aid understanding of the topic, and enabling readers to be ahead of the technological advances
Efficient Feature Selection With Large and High-dimensional Data

Driven by the advances in technology, large and high-dimensional data have become the rule rather than the exception. Approaches that allow for feature selection with such data are thus highly sought after, in particular, since standard methods, like cross-validated Lasso, can be computationally intractable and, in any case, lack theoretical guarantees. In this paper, we propose a novel approach to feature selection in regression. Consisting of simple optimization steps and tests, it is computationally more efficient than existing methods and, therefore, suited even for very large data sets. Moreover, in contrast to standard methods, it is equipped with sharp statistical guarantees. We thus expect that our algorithm can help to leverage the increasing volume of data in Biology, Public Health, Astronomy, Economics, and other fields.
Balanced Wideband Phase Shifters With Wide Phase Shift Range and Good Common-Mode Suppression

This paper proposes a class of balanced wideband phase shifters with wide phase shift range and good common-mode (CM) suppression. Both the balanced filtering units in the reference and main branches consist of horizontal half-wavelength branches and vertical quarter-wavelength loaded stubs but with dissimilar sizes. The differential-mode (DM) section of these two units can achieve ( $2N + 1$ )th-order Chebyshev amplitude response while with discrepant phase characteristics, which can be utilized in the design of balanced phase shifters with large phase shift. As another interesting feature, the proposed balanced filtering unit functions as the conventional branch-line bandstop response in CM, and its frequency selectivity can be further enhanced by using the so-called signal-interference method. The proposed balanced wideband phase shifters have the advantages of wide phase shift range, low phase deviation, high level and wide range for CM rejection in both two branches. The 30°, 60°, 90°, 120°, 150°, and 180° balanced phase shifters are then studied and designed. As the typical examples, 30°, 90°, and 180° phase shifters are designed, fabricated, and measured. The 30° and 90° phase shifters have a fifth-order Chebyshev response, while the 180° phase shifter is of fifth-order and third-order Chebyshev responses in the reference and main branches, respectively. The measured results show that the phase shift values are 30.14° ± 2.2°, 90.75° ± 4.05°, and 180.1° ± 5.5°, the phase shift bandwidths are 73%, 68.5%, and 66.8%, and the CM rejections are −23.3, −22, and −14.6 dB, respectively.
Object tracking from airborne video using particle filters algorithm on dynamic feature fusion

Abstract A particle filter object video tracking algorithm based on dynamic feature fusion is proposed in this paper. This algorithm uses the complementary features, which are gray histogram and gradient histogram, to represent the object model. In the process of tracking, the confidence for each feature is adjusted according to the discrimination between the object and the background, and the object model is dynamically established and updated online. The presented method can improve the accuracy of the object modeling and furthermore improve the accuracy of the particle filter tracking algorithm. Experimental results have demonstrated the effectiveness of our approach for airborne platform video.
An Empirical Comparison between Partial Likelihood and Penalized Partial Likelihood Estimators for Semi-parametric Non-proportional Hazards Models with Frailty

This study compared partial likelihood (PL) and penalized partial likelihood (PPL) estimators in non-proportional hazards model with dichotomous time-varying covariates and subject–specific frailty. We considered Gamma and Inverse Gaussian as frailty distributions. The methods were illustrated with a dataset on diabetes. Extensive numerical studies were conducted using Monte Carlo simulations to compare the efficacy of the methods in terms of Relative Bias (RB) and Root Mean Square Error (RMSE). A sensitivity analysis was carried out to assess the power of the estimators under misspecification of frailty distributions. It was found, that PPL estimator generally outperformed PL estimator in all scenarios considered. Efficiency was found to increase with increase in sample size, and decrease with increase in censoring proportion. The sensitivity analysis conducted to assess the effect of frailty misspecification revealed that sample size, proportion of censored observations and the shape of the frailty distribution (log-skewed) severely affected the power of the estimators.
Characterization of the Agilkia region through discrete-element simulation of Philae’s rebound

Context. The cold gas system and anchoring harpoons that were designed to hold Philae down after it landed on the Agilkia region of comet 67P/Churyumov-Gerasimenko (67P) failed. This caused the lander to move on a complex trajectory that comprised multiple impacts and rebounds. The motion of Philae was mainly dominated by the gravitational environment and the physical properties of the surface on Agilkia. This allows us to determine the physical properties of the surface layer by high-fidelity discrete-element simulations of Philae’s rebounds. Aims. We explore the surface physical properties of the Agilkia region on comet 67P by minimizing the difference in Philae’s rebound status between observational data and simulations based on the assumption of a granular-boulder hybrid surface material. Methods. We first developed an efficient gravity model to accurately approximate the high-resolution polyhedral shape of the comet. This allowed us to run many simulations for the landing trajectory. We developed a complete dynamical model of the motion of Philae, including a mechanical model of the lander and the hybrid surface model. This focused in particular on the interaction of discrete elements in Philae and the granular regolith layer with a boulder added on top of it. We used mixed discrete optimization to determine the input physical variables on Agilkia to fit the rebound observational data (Philae’s rebound velocity). Results. The discrete-element simulation constrained by Philae’s rebound velocity implies that Philae first impacted on a boulder and scratched it with the landing gear. After this, its three soles interacted with the granular regolith, which consists of particles with a mean diameter of 0.014 ± 0.004 cm. The thickness of the region interaction is estimated to be 0.272 ± 0.062 m with a corresponding density of 1443 ± 231 kg m−3. The Young modulus for each particle is estimated to be 108 Pa. Based on a porosity of 0.75, the friction of the surface of particles is derived to be moderate, with a friction coefficient of about 0.6.
Synthesizing Anatomical Images for Image Understanding

The main goals of research in medical and biomedical imaging are to create "better" imaging systems, more accurate reconstructions, and develop methods of image processing that utilize the most important information present in an image or set of images, for accurate, timely, and cost-effective diagnosis and treatment of disease. How well desired information can be extracted best serves to define image quality and consequently the performance of imaging systems. Furthermore, as we deepen our understanding of medical images, new systems and new methods of image processing and image display may help optimize performance and assist radiologists in their challenge for accurate diagnostics. Image quality is thus best measured by the performance of an observer on specific tasks [1]. The observer may be human such as a physician making a diagnosis, or a mathematical model such as an ideal observer [2], or a computer algorithm. Specific tasks may be the detection of a lesion in a chest x ray [3], the estimation of the percent stenosis of a detected aneurysm [4], or the registration of images such as the superimposition of anatomical atlases on patient data [5]. Regardless of the task considered, however, methods to assess image quality based on task performance are most important. Traditionally, the conception of improved imaging systems in medical imaging has been accomplished by designing and constructing proposed systems and characterizing them from an engineering point of view, by reporting parameters such as resolution, modulation transfer function, and pixel signal-to-noise ratio. Naturally, such evaluation is not sufficient to predict the performance that the system will have in the clinic, given that it does not take into account either information about the types of objects being imaged or the tasks being carried out. To fully assess the system, clinical trials based on specific tasks must be conducted. While clinical trials are required for final system assessment, the reliance on clinical trials for system design and optimization has severe limitations. First, the construction of proposed systems is costly and time consuming. In addition, if the system requires further optimization, it may take multiple trials and errors to find the best set of parameters and tradeoff to satisfy required task-based image-quality criteria. Finally, it is nearly impossible to know the anatomical underlying structures of the acquired clinical images unless the diagnosis is verified by physical examination. Instead, disease states are most often estimated by interpreting the images and looking for correlation with previous cases established statistically as well. The approach of building systems and conducting trial-and-error changes based on clinical images thus constitutes a highly impractical means of optimizing imaging systems.
GIADA microbalance measurements on board Rosetta: submicrometer- to micrometer-sized dust particle flux in the coma of comet 67P/Churyumov-Gerasimenko

Context. From August 2014 to September 2016, Rosetta escorted comet 67P/Churyumov-Gerasimenko (67P) during its journey around the Sun. One of the aims of Rosetta was to characterize cometary activity and the consequent formation of dust flux structures in cometary comae. Aims. We characterize and quantify the submicrometer- to micrometer-sized dust flux that may be shaped in privileged directions within the coma of 67P inbound to and outbound from perihelion. Methods. The in situ dust-measuring instrument GIADA, part of the Rosetta/ESA payload, consisted of three subsystems, one of which was the Micro Balance Subsystem (MBS), composed of five quartz crystal microbalances. From May 2014 to September 2016, MBS measured the submicrometer- to micrometer-sized deposited dust mass every 5 min. Results. We characterized the submicrometer- to micrometer-sized dust mass flux in the coma of 67P. The anti-sunward and the radial direction are preferred, and the flux is higher in the anti-sunward direction. The measured cumulative dust mass in the anti-sunward direction is 2.38 ± 0.04 × 10−7 kg, and in the radial direction, it is 1.18 ± 0.02 × 10−7 kg. We explain the anti-sunward dust flux as the effect of nonuniform gas emission between the night- and dayside of the nucleus, which acts in combination with the solar radiation pressure. We compared the cumulated dust mass of particles ≤5 μm with particles ≥100 μm. The retrieved ratio of ≈2% implies a differential size distribution index of ≈−3.0, which confirms that particles of size ≥0.1 mm dominate the dust coma cross-section of 67P during the entire orbit. Conclusions. Submicrometer- to micrometer-sized dust mass flux measurements were made for the first time from the arising of cometary activity until its extinction. They indicate that these particles do not provide a substantial optical scattering in the coma of 67P with respect to the scattering caused by millimeter-sized particles. In addition, MBS data reveal that the measured dust flux is highly anisotropic: anti-sunward plus radial.
Determining the Nature of Super Fluidity and Superconductivity in Dense Matter from Neutron Star Observations

I present a quantitative analysis that utilizes observations of neutron stars to constrain the magnitude of the neutron superfluid gap and the proton superconducting gap in dense matter. In the context of the minimal cooling model, the most likely range for the neutron triplet superfluid gap is 2.09 −1.41 × 10 K and the most likely range for the the proton singlet superconducting gap is 7.59 −5.81 × 10 K. In a second analysis, I confirm these basic predictions for the gaps and additionally determine the mass and envelope composition of the neutron stars in our data set. This analysis shows that some neutron stars are likely more massive and thus cool by the direct Urca process. It also shows that the minimal cooling model may not be the best explanation of neutron star cooling observations. Finally, these quantitative results show that further observations of neutron star cooling will continue to provide constraints on both the equation of state and the transport properties of dense matter.
Piezoelectric Actuators with Uncertainty: Observer-Based Hysteresis Compensation and Joint Stability Analysis

This brief considers sliding mode control of hysteresis in piezoelectric actuators. For modeling of hysteresis, the Bouc–Wen model that is based on differential equations is utilized. One of the states of this model is unmeasurable. Therefore, a state observer is proposed, and the proper selection of observer parameters is discussed. Based on the observed state, a control rule is proposed, and asymptotic stability of the observer-based closed-loop system is proven using the Lyapunov theory. This brief also presents a design method, i.e., sufficient conditions on design parameters for closed-loop stability are derived explicitly. Furthermore, the mass, stiffness, and damping coefficients in the model are assumed unknown. The values of these parameters are estimated using an online adaptation rule, and the control rule is modified based on the estimated parameters. The adaptation rule is extracted so that the asymptotic stability of the whole system is guaranteed. Simulation and experimental results are presented to demonstrate the effectiveness of the proposed scenarios.
A SiGe-Based 240-GHz FMCW Radar System for High-Resolution Measurements

In this paper, a fully integrated silicon-germanium (SiGe)-based compact high-resolution frequency-modulated continuous-wave (FMCW) radar sensor working in a frequency range from 198 to 250 GHz is presented. The wide modulation bandwidth of 52 GHz enables a range resolution better than 3 mm combined with a measurement accuracy in the micrometer regime. Together with a low power consumption of approximately 3.5 W, a high-focusing Teflon lens antenna, and a compact and robust housing, the presented radar system is capable of satisfying the needs of several novel measuring tasks. A compensated measurement accuracy of down to −0.5–0.4 $\mu \text{m}$ is achieved, which is demonstrated by distance measurements using a laser interferometer reference. Additionally, a calibration technique is shown enabling multi-target measurements reaching to the theoretical limit of the range resolution. As the fundamental feedthrough of common frequency doubler architectures cause false targets in the range profile, a dielectric fundamental frequency filter is presented as well, filtering the fundamental feedthrough signal and thus removing the false target, improving the unambiguousness of the presented radar sensor.
A Study on Big data Reliable Combination Evaluation Method based on the Cloud Service Qos Model

The vigorous development of various technologies in the cloud computation field promotes the development and progress of cloud services. But with the large accumulation of information data in the cloud services, in order to meet user’s needs of cloud services multi-function, the operation capacity of a single cloud service is not enough. Now, combining two or many cloud services is a hot research problem. The other hot research problem is that the task of data construction is assigned to different cloud service platforms. However, the combination schemes are too much, so how to ensure the optimal scheme is credible? It has become the key to solve the problem. After reading a large number of literatures, the paper proposes the big data reliable combination evaluation method based on the cloud service QoS model. By getting the contribution of each of the services in the combination scheme set, the method chooses the optimal cloud service combination scheme. Then the optimal scheme is evaluated its reliability.
Comisionamiento del sistema integrado de radiocirugía Varian ICVI.

La radiocirugia es una tecnica de radioterapia compleja que requiere altos niveles de precision debido a la elevada dosis entregada de forma hipofraccionada sobre un pequeno volumen rodeado por estructuras de riesgo. Para resguardar dichas estructuras y generar alto gradiente de dosis, la tecnica puede ser administrada mediante colimadores conicos, los cuales conforman campos considerados pequenos. Trabajar con dichos campos implica dificultades dosimetricas, por lo cual se han desarrollado nuevos protocolos. Se comisiono el sistema de radiocirugia ICVI de Varian, que incluye colimadores conicos de 4 mm, 5 mm, 7,5 mm, 10 mm, 12,5 mm, 15 mm y 17,5 mm, a ser usado en un acelerador TrueBeam STx® con energias 6 MV y 10 MV, con y sin filtro aplanador. Se midieron perfiles, curvas de dosis en profundidad y output factors, tal como lo requiere el software de planificacion Eclipse™ Cone Planning. Se utilizaron detectores Edge™, microDiamond™ y Diodo E™, asi como el fantoma 3D Scanner™, y los resultados se compararon con los datos de referencia del fabricante. Los perfiles y curvas de dosis en profundidad calculados se validaron utilizando diferentes criterios gamma. Tambien se realizo un estudio End-to-End con el fantoma StereoPhan™ y la camara de ionizacion PinPoint® 3D. Los conos iguales o mayores a 7,5 mm mostraron concordancia dentro del 2% entre lo medido y lo calculado. Se requiere otro metodo de validacion para los conos mas chicos.