Miracle-dz/UniFAR-FTUs huggingface dataset:
A comparison of turbulent transport in a quasi-helical and a quasi-axisymmetric stellarator

Ion-temperature-gradient-driven (ITG) turbulence is compared for two quasi-symmetric (QS) stellarator configurations to determine the relationship between linear growth rates and nonlinear heat fluxes. We focus on the quasi-helically symmetric (QHS) stellarator HSX and the quasi-axisymmetric (QAS) stellarator NCSX. In normalized units, HSX exhibits higher growth rates than NCSX, while heat fluxes in gyro-Bohm units are lower in HSX. These results hold for simulations made with both adiabatic and kinetic electrons. The results show that HSX has a larger number of subdominant modes than NCSX and that eigenmodes are more spatially extended in HSX. We conclude that the consideration of nonlinear physics is necessary to accurately assess the heat flux due to ITG turbulence when comparing QS stellarator equilibria.
Consumo Energético x Qualidade de Serviço em Centros de Dados

Provedores de nuvem computacional precisam garantir acordos de nível de serviço, mas também precisam economizar energia em seus centros de dados devido aos altos custos operacionais e ambientais. Trabalhos recentes propõem algoritmos para redução do consumo de energia em centros de dados que consideram, geralmente, uma ou duas das três dimensões de maior consumo energético, quais sejam, servidores, sistema de refrigeração ou infraestrutura de rede. Entretanto, algoritmos que otimizam apenas uma ou duas dessas dimensões podem esconder perdas de energia significativas nas demais dimensões. Além disso, otimizações de energia podem aumentar os tempos de resposta de serviços e violar acordos de nível de serviço. Este artigo apresenta um estudo extensivo das relações entre as três principais dimensões de consumo de energia de um centro de dados e seus impactos em indicadores de qualidade de serviço. O artigo também propõe um algoritmo de alocação de máquinas virtuais que explora diferentes níveis de utilização do centro de dados para economizar energia de forma mais agressiva ou para minimizar violações em acordos de nível de serviço e apresenta um novo simulador para estudos de eficiência energética de centros de dados que permite a avaliação de vários algoritmos de escalonamento sob diferentes cargas de trabalho, estratégias de resfriamento e otimizações de rede. Os resultados experimentais foram obtidos por mais de 500 simulações com três traços reais de cargas de trabalho de até 696 mil máquinas virtuais ao longo de até 34 dias.
Keamanan RESTful Web Service Menggunakan JSON Web Token (JWT) HMAC SHA-512

Day to day information technology is constantly evolving, allowing a wide range of technologies, programming languages, and diverse architectures to keep popping up. It makes a new problem because at present all these differences must still be able to generate an interconnected information. It needs system integration. Currently, Web Service (WS) is a solution in system integration because it can be used without looking at the platform, architecture, or programming language used by different sources. But, on WS, the existing security is still considered less. Implementation of JSON Web Token (JWT) on WS is very influential in data security. JWT is an authentication mechanism on WS, but the application of standard JWT with HMAC SHA-256 algorithm is still not optimal. Therfore, this study discussed JWT security optimization with HMAC SHA-512 algorithm, which according to some researches, this algorithm will be better than SHA-256 if compiled on 64-bit architecture. The result of this research is that the use of SHA-512 produces a better time of 1% than SHA-256, but in SHA-512 token size is 2% larger than SHA-256.
The quantum Monty Hall problem

We consider a variation of the Monty Hall problem and we present a quantum version of it in which the quiz show master does not know where the prize is and can accidentally reveal it. We prove that if the quiz show master is allowed to play quantum and the player is not the game becomes a fair game in contrast with the classical version of the game.
How the urban environment affects the microclimate and the building energy demand for the City of Rome

Urban heat island has significant impacts on buildings? energy consumption. The phenomenon is associated with increased urban air temperatures compared to the air temperature of the surrounding rural or suburban areas. The ambient air temperature growth due to climate changes and the urban heat island phenomenon are dramatically increasing the cooling demand in buildings. This is worsened by irradiation conditions, construction technologies, and subjective comfort expectations. This paper examines the impact of the urban environment on the energy demand of buildings, considering the case of two districts of the city of Rome, Italy: one is representative of a central zone, the other of a rural zone. Weather data were then used to calculate the thermal demand of a typical Italian building, ideally located in the monitored areas of the city. Standalone building with modified weather file was modeled in TRNSYS. Results show that urban heat island intensity causes an increase in cooling demand up to +33% for the urban area (+20% for the rural area) compared to the demand calculated using weather data from airportual areas. On the other hand, urban heat island intensity has a positive effect on heating demand which turns out to decrease up to -32% for the urban area (-14% for the rural area).
Integrated control of a multiple-degree-of-freedom hand and arm using a reactive architecture based on high-speed proximity sensing

We describe integrated control of a multiple-degree-of-freedom hand and arm using a simple reactive architecture based on high-speed proximity sensing. A proximity sensor installed on each fingertip of the hand detects the positions between the sensor and the surface of an object. By feeding back the sensor outputs, the reactive architecture simultaneously controls the position of the arm tip and the vector connecting the grasping position and the origin of the arm tip coordinates, the wrist posture, and the initial finger configurations before grasping. This architecture makes it possible to correct position errors. In addition, since the positions and postures are controlled without contact, there is no danger of damaging the object or the robot. To realize this integrated control using a simple reactive architecture, we designed a high-speed proximity sensor for the fingertips of the hand, and developed an integrated control system for the hand and the arm. We demonstrate high-speed position adjustment motion and grasping for static and moving objects in experiments.
Study on influence of various wind farm correlations on voltage stability with multidimensional data streams method

ABSTRACT Recently, the size of wind farms has been increasing. Large-scale grid-connection of wind farms has a great influence on power system voltage stability. Most of the current research methods consider the correlation of only a single variable, which is not accurate enough for the description of actual production, where there are many variables. This paper presents a multidimensional data stream method to analyze correlations. This method can analyze the correlation degree between wind speed, fan fault, and other variables. It needs only real-time data collected by wind farm, and does not need to construct complicated correlation functions. It overcomes the disadvantage of the state model of traditional wind farms which is not accurate enough, and brings large errors to the analysis results. The method is totally based on measured data so that it is relatively quick and has the potential to be implemented in real-world applications. Then, this method is used to study the influence of correlations on power system voltage stability. A case study based on the standard IEEE 24-bus power system validates the proposed method. Under various working conditions, the numerical simulation results also show that the proposed method has good robustness and applicability.
Spiral spin structures and skyrmionsin multiferroics

Abstract In this article, we focus on (1) type-II multiferroics driven by spiral spin orderings and (2) magnetoelectric couplings in multiferroic skyrmion-hosting materials. We present both phenomenological understanding and microscopic mechanisms for spiral spin state, which is one of the essential starting points for type-II multiferroics and magnetic skyrmions. Two distinct mechanisms of spiral spin states (frustration and Dzyaloshinskii–Moriya [DM] interaction) are discussed in the context of the lattice symmetry. We also discuss the spin-induced ferroelectricity on the basis of the symmetry and microscopic atomic configurations. We compare two well-known microscopic models: the generalized inverse DM mechanism and the metal-ligand d-p hybridization mechanism. As a test for these models, we summarize the multiferroic properties of a family of triangular-lattice antiferromagnets. We also give a brief review of the magnetic skyrmions. Three types of known skyrmion-hosting materials with multiferroicity are discussed from the view point of crystal structure, magnetism, and origins of the magnetoelectric couplings. For exploration of new skyrmion-hosting materials, we also discuss the theoretical models for stabilizing skyrmions by magnetic frustration in centrosymmetric system. Several basic ideas for material design are given, which are successfully demonstrated by the recent experimental evidences for the skyrmion formation in centrosymmetric frustrated magnets.
Domain orientations and piezoelectric properties in novel 2–2-type composites with two single-crystal components

Abstract The present paper is concerned with the piezoelectric properties and related parameters of the 2–2-type parallel-connected composites wherein rotations of the main crystallographic axes in ferroelectric single crystal components are analyzed. The composite consists of layers of two types that are regularly arranged along the non-polar axis. The Type I layer is a single domain 0.63Pb(Mg1/3Nb2/3)O3–0.37PbTiO3 single crystal (either tetragonal in Composite I or orthorhombic in Composite II). The Type II layer is a Li2B4O7 single crystal/polyethylene medium with 0–3 connectivity. The composite as a whole is characterized by 2–0–2 connectivity. The following parameters of the composite are studied by taking into account the polarization orientation effect in the Type I layer and the microgeometry of the composite in the Type II layer: piezoelectric coefficients and their hydrostatic analogs and hydrostatic squared figure of merit piezoelectric anisotropy factors / and / It is shown that large values of the studied piezoelectric coefficients, hydrostatic parameters and anisotropy factors make Composite II more preferable in comparison to Composite I for hydroacoustic, piezoelectric sensor and energy-harvesting applications.
Wideband High-Efficiency Circularly Polarized SIW-Fed S-Dipole Array for Millimeter-Wave Applications

A wideband high-efficiency millimeter-wave (mm-wave) circularly polarized (CP) array which is constituted by novel planar substrate integrated waveguide (SIW)-fed S-dipoles is presented in this communication. The proposed mm-wave CP S-dipole consists of two rotational symmetric curved arms and is fed differentially through aperture coupling, which features simple configuration and excellent performance. Detailed analysis is given to explain the operating principles of this element. It is noted that superior element performance including a wide impedance bandwidth of 43%, a wide 3 dB axial ratio (AR) bandwidth of 36%, and 1 dB gain bandwidth of 38% is achieved by the planar SIW-fed S-dipole. By feeding 64 in-phase S-dipole elements through a full-corporate SIW feeding network, a planar wideband highly efficient mm-wave $8 \times 8$ CP array is realized. To verify the design concept, a prototype operating at Ka-band is fabricated and measured. The measurement results indicate that the proposed array achieves a wide overlapped bandwidth of 27.6%, a high antenna gain of 25.2 dBic, and a high aperture efficiency of 89.9%. Attributed to the planar and robust array structure as well as its excellent performance, the presented array is a good candidate for various mm-wave applications.
HUMAN BRAIN WHITE MATTER ANALYSIS USING TRACTOGRAPHY —AN ATLAS-BASED APPROACH

The human brain is connected via a vastly complex network of white matter fiber pathways. However, this structural connectivity information cannot be obtained from conventional MRI, in which much of white matter appears homogeneous. Diffusion tensor imaging can estimate fiber orientation by measuring the anisotropy of water diffusion. Using tractography, the brain connectivity can be studied non‐invasively. Past tractography studies have shown that the cores of prominent white matter tracts can be faithfully reconstructed. Superimposing the tract coordinates on various MR images, MR metrics can be quantified in a tract‐specific manner. However, tractography results are often contaminated by partial volume effect and imaging noise. Particularly, tractography often fails under white matter pathological conditions, which render tract‐specific analysis impractical. In order to address these issues, we introduced an atlas‐based approach. Four novel atlas‐based approaches were included in this data analysis framework. First, statistical templates of major white matter tracts were created using a DTI database of normal subjects. The statistical white matter tract templates can serve two purposes. First, the statistical template can be used as a reference to detect abnormal white matter anatomy in neurodegenerative diseases. Second, the statistical template can be applied to individual patient data for automated white matter parcellation and tract‐specific quantification. In the second approach, the trajectory of white matter fiber bundles was used to estimate the cortical regions associated with specific tracts of interest. Using this approach, cortical regions were reproducibly identified on the population‐averaged cortical maps of brain connectivity. Third, we improved the accuracy of the population‐based tract analysis by incorporating a highly elastic image transformation technique, called Large Deformation Diffeomorphic Metric Mapping (LDDMM). As a testament to the power of this algorithm, we successfully applied tract‐specific analysis on Alzheimer's patients. The last approach was to analyze the brain cortical connection networks using automatic fiber tracking. A tracking pipeline was built by combining White Matter Parcellation Map (WMPM), brute‐force tractography and topology‐preserving image transformation LDDMM. This novel tracking pipeline was applied on patient group with Alzheimer's disease. The connectivity networks of Alzheimer's patients were compared with age‐matched controls using multivariate pattern classification.
Theoretically Automated Conversations: Collaborative Artistic Creativity for Autonomous Machines

The race is afoot to build fully autonomous systems that equal human performance capacities, particularly for autonomous driving and navigation situations. If we are to create fully autonomous intelligent systems made to successfully interact with humans, fundamental questions pertaining to complex human cognition such as improvisatory and collaborative real-time adaptive problem-solving, decision-making, and action must be seriously addressed, solidly understood, and adequately integrated. To address such high-order human cognition, experiments can no longer be singular and reductive; instead, they must implement relevant observations from spontaneous human behavior within real-world dynamic contexts and innovate sensory-rich experimental paradigms to reliably elicit and record behavioral, physiological, and neural output. With these goals in mind, this paper’s contribution is three-fold: (1) I lay out the motivating and increasingly specific theoretical factors behind original multidisciplinary cognitive behavioral research in the domain of spontaneous human-human communication dynamics within an artistic multisensory context; (2) I break down improvisatory problem-solving and decision-making processes within the performing arts (i.e. drama and music); and (3) I discuss analogous collaborative human-machine interaction situations for autonomous vehicle research and development.
Simulations of the Gravothermal Collapse Phase in Self-Interacting Dark Matter Halos

Non-cosmological N-body simulations of isolated self-interacting dark matter halos were carried out with two initial density profiles, the Hernquist profile and the NFW profile, for different self-interaction cross sections. The evolution of the halos’ central regions are examined during the gravothermal collapse phase. The evolution turns out to be dependent on both the cross section as well as the initial density profile. By applying the mass-concentration-redshift relation for cold dark matter halos presented by Ludlow et al. (2014) one can calculate the mass accretion history as a function of the current halo mass. The mass accretion history is used to approximate the redshift when self-interactions begin affecting the structure of the halos. From this starting redshift, and by using our simulation results as a calibration, we obtain a prediction for the time it takes for self-interacting dark matter haloes to complete the gravothermal collapse phase (and possibly form a black hole), as a function of the halo mass today.
Steady-state analysis of DC converter using Galerkin’s method

Purpose The purpose of this paper is to present the Galerkin method for analysis of steady-state processes in periodically time-varying circuits. Design/methodology/approach A converter circuit working on a time-varying load is often controlled by different signals. In the case of incommensurable frequencies, one can find a steady-state process only via calculation of a transient process. As the obtained results will not be periodical, one must repeat this procedure to calculate the steady-state process on a different time interval. The proposed methodology is based on the expansion of ordinary differential equations with one time variable into a domain of two independent variables of time. In this case, the steady-state process will be periodical. This process is calculated by the use of the Galerkin method with bases and weight functions in the form of the double Fourier series. Findings Expansion of differential equations and use of the Galerkin method enable discovery of the steady-state processes in converter circuits. Steady-state processes in the circuits of buck and boost converters are calculated and results are compared with numerical and generalized state-space averaging methods. Originality/value The Galerkin method is used to find a steady-state process in a converter circuit with a time-varying load. Processes in such a load depend on two incommensurable signals. The state-space averaging method is generalized for extended differential equations. A balance of active power for extended equations is shown.
Detection of Hα emission from PZ Telescopii B using SPHERE/ZIMPOL

Hα is a powerful tracer of accretion and chromospheric activity, which has been detected in the case of young brown dwarfs and even recently in planetary mass companions (e.g. PDS70 b and c). Hα detections and characterisation of brown dwarf and planet companions can further our knowledge of their formation and evolution, and expanding such a sample is therefore our primary goal. We used the Zurich Imaging POLarimeter (ZIMPOL) of the SPHERE instrument at the Very Large Telescope (VLT) to observe the known 38−72 MJ companion orbiting PZ Tel, obtaining simultaneous angular differential imaging observations in both continuum and narrow Hα band. We detect Hα emission from the companion, making this only the second Hα detection of a companion using the SPHERE instrument. We used our newly added astrometric measurements to update the orbital analysis of PZ Tel B, and we used our photometric measurements to evaluate the Hα line flux. Given the estimated bolometric luminosity, we obtained an Hα activity (log(LHα/Lbol)) between −4.16 and −4.31. The Hα activity of PZ Tel B is consistent with known average activity levels for M dwarf of the same spectral type. Given the absence of a known gaseous disk and the relatively old age of the system (24 Myr), we conclude that the Hα emission around PZ Tel B is likely due to chromospheric activity.
Liver autophagy in the influenza B virus model of Reye's syndrome in mice

Biochemical evidence is presented for the autophagic destruction of liver mitochondria in the influenza B virus model of Reye's syndrome in mice. Separation of lysosomes and autophagic vacuoles from mitochondria was accomplished by prior treatment of the mice with Triton WR‐1339, resulting in uptake of detergent by these organelles (tritosomes), reducing their densities. The organelles were banded in a discontinuous sucrose gradient. Total protein in the heavy tritosomal fraction increased from 1–2% in controls to 7–8% in virus‐treated animals. Ornithine carbamoyl transferase (OCTase), a mitochondrial marker, increased from 2–3% (controls) to 11–15% (virus‐treated), and glucose‐6‐phosphatase, a marker for endoplasmic reticulum, increased from 1–2% (controls) to 8–10% (virus‐treated). β‐Galactosidase, a soluble enzyme in the lysosome, and OCTase also increase in the cell extract fraction following virus treatment, indicating that there was turnover of heavy lysosomal contents.
Rational Polynomial Chaos Expansions for the Stochastic Macromodeling of Network Responses

This paper introduces rational polynomial chaos expansions for the stochastic modeling of the frequency-domain responses of linear electrical networks. The proposed method models stochastic network responses as a ratio of polynomial chaos expansions, rather than the standard single polynomial expansion. This approach is motivated by the fact that network responses are best represented by rational functions of both frequency and parameters. In particular, it is proven that the rational stochastic model is exact for lumped networks. The model coefficients are computed via an iterative re-weighted linear least-square regression. Several application examples, concerning both lumped and a distributed systems, illustrate and validate the advocated methodology.
A Review of Actuation Force in Origami Applications

Origami, the ancient paper folding art has inspired the engineering equipment and design for decades. The basic concept of origami is very general, which leads to applications ranging from small scale to large scale. Recently, researchers are interested in being able to create self-folding structures. Such a structure enables kinematic manipulation by external forces or moments without folding and/or unfolding operations. This is a beneficial application for many fields including aerospace systems, robots, small devices and self-assembly systems. In this paper, the investigation and analyses of the previous literatures on the key driving force of the actuation structure, including the heat, light, electricity, gas and other actuation methods. The aims are to provide researchers and practitioners with the support to systematically understand the latest technologies in this important and evolving field, with inspiration and direction for follow-up.