Miracle-dz/UniFAR-FTUs huggingface dataset:
The Activation Energy for Wall Slip

The Navier slip boundary condition is interpreted as an equilibrium of shear rate and slip rate. From the argument that the slip rate shall be proportional to the molecules’ collision rate, the temperature dependence of the Navier slip boundary condition is derived. The model for the temperature dependence of the slip length is validated by slip measurements of liquid hydrocarbons in a novel Couette typ tribometer being introduced. The essence of the gained experimental data for one fluid-solid-interface is the quadruple activation energy for shear and wall slip together with the viscosity and slip length at a reference temperature. This quadruple is determined for four different hydrocarbon liquids of different molecular mass, structure and polarity proving the applicability of the new measurement method. From the executed systematic measurements three conclusions regarding the slip length dependence are pointed out: (i) the slip length increases with increasing molar mass; (ii) changing the molecular structure from saturated hydrocarbon to unsaturated affects the slip length as well as the activation energy for slip; (iii) adding a small fraction of polar molecules to the hydrocarbon decreases the slip length and increases the activation energy for wall slip due to the polar end-groups of the liquid.
Design and Analysis of Wideband In-Band-Full- Duplex FR2-IAB Networks

This paper develops a 3GPP-inspired design for the in- band-full-duplex (IBFD) integrated access and backhaul (IAB) networks in the frequency range 2 (FR2) band, which can enhance the spectral efficiency (SE) and coverage while reducing the latency. However, the self-interference (SI), which is usually more than 100 dB higher than the signal-of-interest, becomes the major bottleneck in developing these IBFD networks. We design and analyze a subarray-based hybrid beamforming IBFD-IAB system with the RF beamformers obtained via RF codebooks given by a modified Linde-Buzo-Gray (LBG) algorithm. The SI is canceled in three stages, where the first stage of antenna isolation is assumed to be successfully deployed. The second stage consists of the optical domain (OD)-based RF cancellation, where cancelers are connected with the RF chain pairs. The third stage is comprised of the digital cancellation via successive interference cancellation followed by minimum mean-squared error baseband receiver. Multiuser interference in the access link is canceled by zero-forcing at the IAB-node transmitter. Simulations show that under 400 MHz bandwidth, our proposed OD-based RF cancellation can achieve around 25 dB of cancellation with 100 taps. Moreover, the higher the hardware impairment and channel estimation error, the worse digital cancellation ability we can obtain.
Study of 72 Pulsars Discovered in the PALFA Survey: Timing Analysis, Glitch Activity, Emission Variability, and a Pulsar in an Eccentric Binary

We present new discoveries and results from long-term timing of 72 pulsars discovered in the Pulsar Arecibo L-band Feed Array (PALFA) survey, including precise determination of astrometric and spin parameters, and flux density and scatter broadening measurements at 1.4 GHz. Notable discoveries include two young pulsars (characteristic ages ∼30 kyr) with no apparent supernova remnant associations, three mode-changing, 12 nulling and two intermittent pulsars. We detected eight glitches in five pulsars. Among them is PSR J1939+2609, an apparently old pulsar (characteristic age ∼1 Gy), and PSR J1954+2529, which likely belongs to a newly emerging class of binary pulsars. The latter is the only pulsar among the 72 that is clearly not isolated: a nonrecycled neutron star with a 931 ms spin period in an eccentric (e = 0.114) wide (P b = 82.7 days) orbit with a companion of undetermined nature having a minimum mass of ∼0.6 M ⊙. Since operations at Arecibo ceased in 2020 August, we give a final tally of PALFA sky coverage, and compare its 207 pulsar discoveries to the known population. On average, they are 50% more distant than other Galactic plane radio pulsars; PALFA millisecond pulsars (MSPs) have twice the dispersion measure per unit spin period than the known population of MSP in the plane. The four intermittent pulsars discovered by PALFA more than double the population of such objects, which should help to improve our understanding of pulsar magnetosphere physics. The statistics for these, rotating radio transients, and nulling pulsars suggest that there are many more of these objects in the Galaxy than was previously thought.
The Feature-First Block Model

Labelled networks are an important class of data, naturally appearing in numerous applications in science and engineering. A typical inference goal is to determine how the vertex labels (or features) affect the network's structure. In this work, we introduce a new generative model, the feature-first block model (FFBM), that facilitates the use of rich queries on labelled networks. We develop a Bayesian framework and devise a two-level Markov chain Monte Carlo approach to efficiently sample from the relevant posterior distribution of the FFBM parameters. This allows us to infer if and how the observed vertex-features affect macro-structure. We apply the proposed methods to a variety of network data to extract the most important features along which the vertices are partitioned. The main advantages of the proposed approach are that the whole feature-space is used automatically and that features can be rank-ordered implicitly according to impact.
Information constraint in open quantum systems

We propose an effect called information constraint which is characterized by the existence of different decay rates of signal strengths propagating along opposite directions. It is an intrinsic property of a type of open quantum system, which does not rely on boundary conditions. We define the value of information constraint ($I_C$) as the ratio of different decay rates and derive the analytical representation of $I_C$ for general quadratic Lindbladian systems. Based on information constraint, we can provide a simple and elegant explanation of chiral and helical damping, and get the local maximum points of relative particle number for the periodical boundary system, consistent with numerical calculations. Inspired by information constraint, we propose and prove the correspondence between edge modes and damping modes. A new damping mode called Dirac damping is constructed, and chiral/helical damping can be regarded as a special case of Dirac damping.
Network Security Situation Awareness Based on Phishing Detection

In this paper, we introduce a statistical machine learning classifier and a LSH page similarity detector as the network security situation awareness mechanism to detect the spear phishing that has been widely used in the Advanced Persistent Threats. Then, a number of comprehensive experiments show that our proposed method achieves high accuracy over a balanced dataset. The accuracy is no less than 92% while the recall is more than 97%.
Optimal turbine spacing in fully developed wind farm boundary layers

As wind farms become larger, the asymptotic limit of the “fully developed”, or “infinite”, wind farm has been receiving increased interest. This limit is relevant for wind farms on flat terrain whose length exceeds the height of the atmospheric boundary layer by over an order of magnitude. Recent computational studies based on Large Eddy Simulation have identified various mean velocity equilibrium layers, and have led to parameterizations of the effective roughness height that allow predicting the wind velocity at hub-height as function of parameters such as wind turbine spacing and loading factors. In the current paper, we employ this as a tool to make predictions of optimal wind turbine spacing as function of these parameters, as well as in terms of the ratio of turbine costs to land-surface costs. For realistic cost ratios, we find that the optimal average turbine spacing may be considerably higher than conventionally used in current wind-farm implementations.
A Coupled-Line Band-Stop Filter with Three-Section Transmission-Line Stubs and Wide Upper Pass-Band Performance

A novel band-stop fllter with wide upper pass-band performance is proposed and discussed in this paper. This band- stop fllter includes two three-section transmission-line stubs and a parallel coupled-line section. Because three-section transmission-line stubs and coupled-line section are used, this fllter not only features good band-stop flltering property, but also has wide upper pass band. In order to verify this new fllter circuit structure and its corresponding design theory, three groups of numerical examples are demonstrated. Finally, two practical band-stop fllters using common microstrip technology are designed, simulated and measured. The simulated and measured results indicate that both the coupled-line section with weak coupling and two three-section stubs can improve the upper pass-band performance. Furthermore, the measured results of the second fabricated microstrip band-stop fllter (Filter B) show that the 20-dB insertion-loss band-stop bandwidth at 0.46GHz is 90MHz and the 1.2-dB transmission coe-cient upper pass band is from 0.66GHz to 2.52GHz. Thus, the highest pass-band frequency is extended to larger than flve times of the operating center frequency of stop band.
ReLaX: the Helmholtz International Beamline for Extreme Fields high-intensity short-pulse laser driver for relativistic laser–matter interaction and strong-field science using the high energy density instrument at the European X-ray free electron laser facility

Abstract High-energy and high-intensity lasers are essential for pushing the boundaries of science. Their development has allowed leaps forward in basic research areas, including laser–plasma interaction, high-energy density science, metrology, biology and medical technology. The Helmholtz International Beamline for Extreme Fields user consortium contributes and operates two high-peak-power optical lasers using the high energy density instrument at the European X-ray free electron laser (EuXFEL) facility. These lasers will be used to generate transient extreme states of density and temperature to be probed by the X-ray beam. This paper introduces the ReLaX laser, a short-pulse high-intensity Ti:Sa laser system, and discusses its characteristics as available for user experiments. It will also present the first experimental commissioning results validating its successful integration into the EuXFEL infrastructure and viability as a relativistic-intensity laser driver.
Steady‐state visual evoked potential responses predict visual discomfort judgements

It has been suggested that aesthetically pleasing stimuli are processed efficiently by the visual system, whereas uncomfortable stimuli are processed inefficiently. This study consists of a series of three experiments investigating this idea using a range of images of abstract artworks, photographs of natural scenes, and computer‐generated stimuli previously shown to be uncomfortable. Subjective judgements and neural correlates were measured using electroencephalogram (EEG) (steady‐state visual evoked potentials, SSVEPs). In addition, global image statistics (contrast, Fourier amplitude spectral slope and fractal dimension) were taken into account. When effects of physical image contrast were controlled, fractal dimension predicted discomfort judgements, suggesting the SSVEP response is more likely to be influenced by distribution of edges than the spectral slope. Importantly, when effects of physical contrast and fractal dimension were accounted for using linear mixed effects modelling, SSVEP responses predicted subjective judgements of images. Specifically, when stimuli were not matched for perceived contrast, there was a positive relationship between SSVEP responses and how pleasing a stimulus was judged to be, and conversely a negative relationship between discomfort and SSVEP response. This is significant as it shows that the neural responses in early visual areas contribute to the subjective (un)pleasantness of images, although the results of this study do not provide clear support for the theory of efficient coding as the cause of perceived pleasantness or discomfort of images, and so other explanations need to be considered.
A recurrent circuit links antagonistic cerebellar modules during associative motor learning

The neural architecture of the cerebellum is thought to be specialized for performing supervised learning: specific error-related climbing fiber inputs are used to teach sensorimotor associations to small ensembles of Purkinje cells located in functionally distinct modules that operate independently of each other in a purely feedforward manner. Here, we test whether the basic operation of the cerebellum complies with this basic architecture in mice that learned a simple sensorimotor association during eyeblink conditioning. By recording Purkinje cells in different modules and testing whether their responses rely on recurrent circuits, our results reveal three operational principles about the functional organization of the cerebellum that stand in stark contrast to the conventional view: (1) Antagonistic organization, (2) Recurrent network dynamics, and (3) Intermodular communication. We propose that the neural architecture of the cerebellum implements these three operational principles to achieve optimal performance and solve a number of problems in motor control.
Skype : a communications framework for robotics

This paper describes an architecture for robotic telepresence and teleoperation based on the well known tools ROS and Skype. We discuss how Skype can be used as a framework for robotic communication and can be integrated into a ROS/Linux framework to allow a remote user to not only interact with people near the robot, but to view maps, sensory data, robot pose and to issue commands to the robot’s navigation stack. This allows the remote user to exploit the robot’s autonomy, providing a much more convenient navigation interface than simple remote joysticking.
Ka-band monolithic InGaAs/InP HBT VCO's in CPW structure

Two Ka-band monolithic voltage controlled oscillators (VCO's) designed in a coplanar waveguide (CPW) structure are described. Each VCO utilizes an InGaAs/InP heterojunction bipolar transistor (HBT) as the active device and an HBT base-collector junction as the tuning varactor. These two VCO's are biased at a very low voltage of V/sub CE/=1.5 V and the emitter current is less than 10 mA. Under this low dc power dissipation, the VCO's with center frequencies of 26.5 and 33.5 GHz show high dc-to-rf conversion efficiencies over 10% and 5% within the frequency tuning ranges of 1.6 and 1.2 GHz, respectively. The measured phase noise at 1 MHz offset frequency is -110 dBc/Hz. >
Complexity Collapse, Fluctuating Synchrony, and Transient Chaos in Neural Networks With Delay Clusters

Neural circuits operate with delays over a range of time scales, from a few milliseconds in recurrent local circuitry to tens of milliseconds or more for communication between populations. Modeling usually incorporates single fixed delays, meant to represent the mean conduction delay between neurons making up the circuit. We explore conditions under which the inclusion of more delays in a high-dimensional chaotic neural network leads to a reduction in dynamical complexity, a phenomenon recently described as multi-delay complexity collapse (CC) in delay-differential equations with one to three variables. We consider a recurrent local network of 80% excitatory and 20% inhibitory rate model neurons with 10% connection probability. An increase in the width of the distribution of local delays, even to unrealistically large values, does not cause CC, nor does adding more local delays. Interestingly, multiple small local delays can cause CC provided there is a moderate global delayed inhibitory feedback and random initial conditions. CC then occurs through the settling of transient chaos onto a limit cycle. In this regime, there is a form of noise-induced order in which the mean activity variance decreases as the noise increases and disrupts the synchrony. Another novel form of CC is seen where global delayed feedback causes “dropouts,” i.e., epochs of low firing rate network synchrony. Their alternation with epochs of higher firing rate asynchrony closely follows Poisson statistics. Such dropouts are promoted by larger global feedback strength and delay. Finally, periodic driving of the chaotic regime with global feedback can cause CC; the extinction of chaos can outlast the forcing, sometimes permanently. Our results suggest a wealth of phenomena that remain to be discovered in networks with clusters of delays.
Flush Flow Behaviour Affected by the Morphology of Intravascular Endoscope: A Numerical Simulation and Experimental Study

Background: Whilst intravascular endoscopy can be used to identify lesions and assess the deployment of endovascular devices, it requires temporary blockage of the local blood flow during observation, posing a serious risk of ischaemia. Objective: To aid the design of a novel flow-blockage-free intravascular endoscope, we explored changes in the haemodynamic behaviour of the flush flow with respect to the flow injection speed and the system design. Methods: We first constructed the computational models for three candidate endoscope designs (i.e., Model A, B, and C). Using each of the three endoscopes, flow patterns in the target vessels (straight, bent, and twisted) under three different sets of boundary conditions (i.e., injection speed of the flush flow and the background blood flowrate) were then resolved through use of computational fluid dynamics and in vitro flow experiments. The design of endoscope and its optimal operating condition were evaluated in terms of the volume fraction within the vascular segment of interest, as well as the percentage of high-volume-fraction area (PHVFA) corresponding to three cross-sectional planes distal to the microcatheter tip. Results: With a mild narrowing at the endoscope neck, Model B exhibited the highest PHVFA, irrespective of location of the cross-sectional plane, compared with Models A and C which, respectively, had no narrowing and a moderate narrowing. The greatest difference in the PHVFA between the three models was observed on the cross-sectional plane 2 mm distal to the tip of the microcatheter (Model B: 33% vs. Model A: 18%). The background blood flowrate was found to have a strong impact on the resulting volume fraction of the flush flow close to the vascular wall, with the greatest difference being 44% (Model A). Conclusion: We found that the haemodynamic performance of endoscope Model B outperformed that of Models A and C, as it generated a flush flow that occupied the largest volume within the vascular segment of interest, suggesting that the endoscope design with a diameter narrowing of 30% at the endoscope neck might yield images of a better quality.
The effects of non-parallel plates in a differential capacitive microaccelerometer

The effects of non-parallel plates on the capacitance, sensitivity, electrostatic force and electrostatic spring constant of a microaccelerometer are investigated. In a deep reactive ion etching similar to the single crystal reactive ion etching and metallization (SCREAM) micromachining process, the width of the fingers increases linearly with depth and the cross section takes on a trapezoidal profile. This non-ideal feature is greater in high aspect ratio structures and significantly affects the capacitance, sensitivity, electrostatic force and electrostatic spring constant of the accelerometer operated in either closed or open loop. Finite-element analyses (FEA) of the capacitance and electrostatic force of the parallel-plate and non-parallel-plate models were completed and the results were compared with those derived from the theoretical approach. It is verified that the capacitance, sensitivity, electrostatic force and electrostatic spring constant of the non-parallel-plate model are larger than the parallel-plate model. Hence this non-ideal feature should not be neglected and the assumption of parallel-plate model would give an underestimate of these physical parameters.
Peroxisomal Membrane Contact Sites in Yeasts

Peroxisomes are ubiquitous, single membrane-bound organelles that play a crucial role in lipid metabolism and human health. While peroxisome number is maintained by the division of existing peroxisomes, nascent peroxisomes can be generated from the endoplasmic reticulum (ER) membrane in yeasts. During formation and proliferation, peroxisomes maintain membrane contacts with the ER. In addition to the ER, contacts between peroxisomes and other organelles such as lipid droplets, mitochondria, vacuole, and plasma membrane have been reported. These membrane contact sites (MCS) are dynamic and important for cellular function. This review focuses on the recent developments in peroxisome biogenesis and the functional importance of peroxisomal MCS in yeasts.
Effects of High-Definition Transcranial Direct Current Stimulation Over the Left Fusiform Face Area on Face View Discrimination Depend on the Individual Baseline Performance

A basic human visual function is to identify objects from different viewpoints. Typically, the ability to discriminate face views based on in-depth orientation is necessary in daily life. Early neuroimaging studies have identified the involvement of the left fusiform face area (FFA) and the left superior temporal sulcus (STS) in face view discrimination. However, many studies have documented the important role of the right FFA in face processing. Thus, there remains controversy over whether one specific region or all of them are involved in discriminating face views. Thus, this research examined the influence of high-definition transcranial direct current stimulation (HD-tDCS) over the left FFA, left STS or right FFA on face view discrimination in three experiments. In experiment 1, eighteen subjects performed a face view discrimination task before and immediately, 10 min and 20 min after anodal, cathodal and sham HD-tDCS (20 min, 1.5 mA) over the left FFA in three sessions. Compared with sham stimulation, anodal and cathodal stimulation had no effects that were detected at the group level. However, the analyses at the individual level showed that the baseline performance negatively correlated with the degree of change after anodal tDCS, suggesting a dependence of the change amount on the initial performance. Specifically, tDCS decreased performance in the subjects with better baseline performance but increased performance in those with poorer baseline performance. In experiments 2 and 3, the same experimental protocol was used except that the stimulation site was the left STS or right FFA, respectively. Neither anodal nor cathodal tDCS over the left STS or right FFA influenced face view discrimination in group- or individual-level analyses. These results not only indicated the importance of the left FFA in face view discrimination but also demonstrated that individual initial performance should be taken into consideration in future research and practical applications.