Miracle-dz/UniFAR-FTUs huggingface dataset:
(Retracted) Design of street art image retrieval system based on virtual simulation technology for the public health environment

Abstract. The Editor-in-Chief and the publisher have retracted this article, which was submitted as part of a guest-edited special section. An investigation uncovered evidence of systematic manipulation of the publication process, including compromised peer review. The Editor and publisher no longer have confidence in the results and conclusions of the article. ZL and JH either did not respond directly or could not be reached.
High-Rate Secret Key Generation Using Physical Layer Security and Physical Unclonable Functions

Physical layer security (PLS) can be adopted for efficient key generation and sharing in secured wireless systems. The inherent random nature of the wireless channel and the associated channel reciprocity (CR) are the main pillars for realizing PLS techniques. However, for applications that involve air-to-air (A2A) transmission, such as unmanned aerial vehicle (UAV) applications, the channel does not generally have sufficient randomness to enable reliable key generation. Therefore, this work proposes a novel system design to mitigate the channel randomness constraint and enable a high-rate secret key generation process. The proposed system integrates physically unclonable functions (PUFs) and CR to generate and exchange secret keys between two nodes securely. Moreover, an adaptive and controllable artificial fading (AF) level with interleaving is used to mitigate the impact of low randomness variations in the wireless channel. Moreover, we propose a novel bit extraction scheme to reduce the number of overhead bits required to share the intermediate keys. The obtained Monte Carlo simulation results show that the proposed system can operate efficiently even when the channel is nearly flat or time-invariant. Consequently, the time required for generating and sharing a key is significantly shorter than conventional techniques. Furthermore, the results show that a key agreement can be reached at the first trial for moderate and high signal-to-noise ratios (SNRs) substantially faster than other PLS techniques. Adopting the AF into static channels managed to reduce the mismatch ratio between the generated secret sequences and degrade the eavesdropper’s capability to predict the secret keys.
Adaptive wavelet filtering for bearing monitoring based on block bootstrapping and white noise test

This study describes a novel scheme of adaptive wavelet filtering for bearing monitoring based on block bootstrapping and white noise test. The scheme consists of three main steps. First, the vibration signal is decomposed into wavelet domain, and the correlations between the wavelet coefficients are measured by lag autocorrelations. Second, according to the intensity of correlation at each level, either the block bootstrapping or general bootstrapping procedure is adopted to produce new pseudo-samples from the original wavelet coefficient series. Finally, as actual signal and noise have different translating characters along the levels in wavelet domain, the optimal decomposition level is achieved through whitening test on the wavelet coefficients, and the accuracy of the test is also obtained by the pseudo-samples. The simulation and experimental results show that the proposed procedure can be used to adaptively determine the optimal decomposition level and obtain superior filtering capability.
Investigating the Performance of a Zinc Oxide Impregnated Polyvinyl Alcohol-Based Low-Cost Cation Exchange Membrane in Microbial Fuel Cells

The current study investigated the development and application of lithium (Li)-doped zinc oxide (ZnO)-impregnated polyvinyl alcohol (PVA) proton exchange membrane separator in a single chambered microbial fuel cell (MFC). Physiochemical analysis was performed via FT-IR, XRD, TEM, and AC impedance analysis to characterize thus synthesized Li-doped ZnO. PVA-ZnO-Li with 2.0% Li incorporation showed higher power generation in MFC. Using coulombic efficiency and current density, the impact of oxygen crossing on the membrane cathode assembly (MCA) area was evaluated. Different amounts of Li were incorporated into the membrane to optimize its electrochemical behavior and to increase proton conductivity while reducing biofouling. When acetate wastewater was treated in MFC using a PVA-ZnO-Li-based MCA, the maximum power density of 6.3 W/m3 was achieved. These observations strongly support our hypothesis that PVA-ZnO-Li can be an efficient and affordable separator for MFC.
Magnetization study of nanograined pure and Mn-doped ZnO films: Formation of a ferromagnetic grain-boundary foam

In order to elucidate room-temperature (RT) ferromagnetism (FM) in ZnO, we have analyzed a multitude of experimental publications with respect to the ratio of grain-boundary (GB) area to grain volume. FM only appears if this ratio exceeds a certain threshold value ${s}_{\text{th}}$. Based on these important results nanograined pure and Mn-doped ZnO films have been prepared, which reveal reproducible RT FM and magnetization proportional to the film thickness, even for pure ZnO films. Our findings strongly suggest that grain boundaries and related vacancies are the intrinsic origin for RT ferromagnetism.
Bimodality of the Planetary-Scale Atmospheric Wave Amplitude Index

Abstract The evidence for multiple flow regimes in the planetary-scale atmospheric wave amplitude index (WAI) is studied using the 56 winters from the NCEP reanalysis data. The regimes are identified by bimodality in the probability density estimates. Both the probability density of the WAI alone and the probability density in the two-dimensional space spanned by the WAI and its temporal rate of change are examined. The latter procedure allows us to exploit the quasi stationarity of the regimes and increase the statistical significance. The statistical significance of bimodality in the probability densities is tested by a Monte Carlo approach using surrogate time series that preserve the full autocorrelation spectrum of the original WAI. By using a longer dataset and including the rate of change, some of the questions raised in previous studies about the robustness and statistical significance of the bimodality of the WAI are resolved. Statistically significant bimodality is found in the WAI based on the .
Reference prior bayes estimator for bivariate normal covariance matrix with risk comparison

The explicit form of the reference prior bayes estimator due to Yang and Ber-ger (1994) for bivariate normal covariance matrix under entropy loss is given in terms of Legendre polynomials when degrees of freedom is even and in terms of hypergeometric functions in general case. The finite series expression of the density function of the ratio of latent roots of bivariate Wishart matrix is obtained and the exact risk is compared with those of James-Stein minimax estimator and other orthogonally equivariant estimators. It is found numerically that the reference prior bayes estimator has the smallest risk among the class of equivariant estimators compared, when the ratio of the largest to the smallest population latent roots of covariance matrix lies in the middle of the interval [1, ∞]. It has larger risk than that of James-Stein minimax estimator when the ratio is large. Moreover it has larger risk than that of MLE when, for instance, degrees of freedom is 20 and the ratio lies between 4 and 8.
Turbulent channel flow with either transverse or longitudinal roughness elements on one wall

Direct numerical simulation results are presented for turbulent channel flows with two-dimensional roughness elements of different shapes. The focus is mainly on a geometry where the separation between consecutive roughness elements is small and for which the rate of change of the roughness function with respect to the separation between consecutive elements is large. Roughness elements are placed either along the flow direction or orthogonally to it. In the latter case, the drag is increased. For the former case, the possibility of drag reduction reflects the different relative contributions from viscous and Reynolds shear stresses. The Reynolds shear stress depends on the shape of the surface more than the viscous stress and is closely related to the near-wall structures. For orthogonal elements, there is no satisfactory correlation between the roughness function and parameters describing the roughness geometry. On the other hand, a satisfactory collapse of the data is achieved when the roughness function is plotted against the root mean square wall-normal velocity averaged over the plane of the roughness crests. Relative to a smooth wall surface, the Reynolds stress tensor near the wall tends to become more isotropic when the elements are orthogonal to the flow and less isotropic when the elements are aligned with the flow. The interdependencies between the departure from isotropy in the wall region, the organization of the wall structures, and the magnitude of the drag are assessed by examining the rotational component of the turbulent kinetic energy production and the probability density function of the helicity density.
A small-scale evaluation of instructional approaches and perspectives on the benefits of adventurous education for young people

The addition of Outdoor and Adventurous Activities (OAA) throughout the national curriculum for physical education in England and Wales has added a new dimension to the often-questioned traditional teaching curricula associated with competitive sport. Yet, the research base linked to the field of OAA has limited insight into the views of the instructors who integrally facilitate such experiences. This study analysed the perspective of instructors regarding their perceptions of the benefits associated with OAA participation for young people, but also some of the pivotal teaching approaches used to optimise such developments. Six OAA instructors from the United Kingdom participated in a cross-sectional qualitative case study and were interviewed to gauge their perspectives on the benefits and teaching approaches utilised in adventurous education. The emerging dominant theme demonstrates a link between the specific and intentional pedagogic strategies of the instructors and the intended developmental outcomes for young people.
Mobile Sensing of Alertness, Sleep and Circadian Rhythm

Human biology is deeply rooted in the daily 24-hour temporal period. Our biochemistry varies significantly and idiosyncratically over the course of a day. Staying out of sync with one's circadian rhythm can lead to many complications over time, including a higher likelihood for cardiovascular disease, cancer, obesity, and mental health problems [1]. Constant changes in daily rhythm due to shift work has been shown to increase risk factors for cancer, obesity, and Type 2 diabetes. Moreover, the advent of technology and the resultant always-on ethos can cause rhythm disruption on personal and societal levels for about 70% of the population [2]. Circadian disruption can also cause a serious deficit in cognitive performance. In particular, alertness - a key biological process underlying our cognitive performance - reflects circadian rhythms [3]. Sleep deprivation and circadian disruption can result in poor alertness and reaction time [3]. The decline in cognitive performance after 20 to 25 hours of wakefulness is equivalent to a Blood Alcohol Concentration (BAC) of 0.10% [4]. To compare, in New York State, a BAC of more than 0.05% is considered "impaired" and 0.08% is considered "intoxicated" [5]. In other words, the effects of sustained sleep deprivation and circadian disruption on cognitive performance is similar (or worse) to being intoxicated.
LARA: Attribute-to-feature Adversarial Learning for New-item Recommendation

Recommending new items in real-world e-commerce portals is a challenging problem as the cold start phenomenon, i.e., lacks of user-item interactions. To address this problem, we propose a novel recommendation model, i.e., adversarial neural network with multiple generators, to generate users from multiple perspectives of items' attributes. Namely, the generated users are represented by attribute-level features. As both users and items are attribute-level representations, we can implicitly obtain user-item attribute-level interaction information. In light of this, the new item can be recommended to users based on attribute-level similarity. Extensive experimental results on two item cold-start scenarios, movie and goods recommendation, verify the effectiveness of our proposed model as compared to state-of-the-art baselines.
RADIATION-INDUCED CHANGES OF DIMENSIONS, INDEX OF REFRACTION, AND DISPERSION OF LITHIUM FLUORIDE

Deuteron, electron, gamma ray, and x-ray irradiated specimens were examined by a photoelastic method and by interferometrie methods. In addition to the increase in physical dimensions, there were found an increase in refractive index and an increase in dispersion, and these were measured. The results agree with the classical dispersion formulas if it is assumed that the effects are caused by a change in the refractivity of the base material due to the introduction of vacancies and holes and a change in the refractivity due to the F centers and the 450 centers, the size of the vacancies being about that of the absent ions and the oscillator strength or the F centers being near unity. (auth)
Measurement of Oscillator Strengths for Three Lines among the 4s4p 3P-4p2 3P Multiplet of Zn I

The hook method has been applied to the 4 s 4 p 3 P 0 -4 p 2 3 P 1 , 4 s 4 p 3 P 1 -4 p 2 3 P 0 and 4 s 4 p 3 P 2 -4 p 2 3 P 1 transitions at 2079 A, 2097 A and 2104 A as well as to the visible multiplet 4 s 4 p 3 P 0,1,2 -4 s 4 s 3 S 1 at 4680 A, 4722 A and 4811 A. Relative oscillator strengths are determined to be f 2079 / f 4680 * =4.4 ±1.1, f 2097 / f 4722 * =1.5 ±0.4 and f 2104 / f 4811 * =1.3 ±0.4. Uisng known f * values of the visible multiplet the g f values are obtained to be g f 2079 =0.63, g f 2097 =0.63 and g f 2104 =0.90.
Quantum size effect dependent critical size cluster and finite size effects

Pb nucleation on top of a unique Pb island grown on Si(7×7) (in the form of a “hub”-“moat”-ring) confirms that electron confinement causes large variations in critical size cluster ic with island height. Because of smaller radial dimensions (less than 20 nm), the large variation of the nucleated island density on different layers cannot be a result of differences in terrace diffusion coefficients but ic. These results have important implications on how adsorption can be dramatically modified by quantum size effects.
SecureCPS: Defending a nanosatellite cyber-physical system

Recent inexpensive nanosatellite designs employ maneuvering thrusters, much as large satellites have done for decades. However, because a maneuvering nanosatellite can threaten HVAs on-orbit, it must provide a level of security typically reserved for HVAs. Securing nanosatellites with maneuvering capability is challenging due to extreme cost, size, and power constraints. While still in the design process, our low-cost SecureCPS architecture promises to dramatically improve security, to include preempting unknown binaries and detecting abnormal behavior. SecureCPS also applies to a broad class of cyber-physical systems (CPS), such as aircraft, cars, and trains. This paper focuses on Embry-Riddle’s ARAPAIMA nanosatellite architecture, where we assume any off-the-shelf component could be compromised by a supply chain attack.1 Based on these assumptions, we have used Vanderbilt’s Cyber Physical - Attack Description Language (CP-ADL) to represent realistic attacks, analyze how these attacks propagate in the ARAPAIMA architecture, and how to defeat them using the combination of a low-cost Root of Trust (RoT) Module, Global InfoTek’s Advanced Malware Analysis System (GAMAS), and Anomaly Detection by Machine Learning (ADML). 2 Our most recent efforts focus on refining and validating the design of SecureCPS.
Electromagnetic TE scattering by a conducting cylinder coated with an inhomogeneous dielectric/magnetic material

The problem of electromagnetic TE scattering by an infinitely long conducting cylinder coated with an inhomogeneous dielectric/magnetic material is analyzed. A volume-surface integral equation (VSIE) approach is utilized to model the problem. By imposing the boundary conditions on the conducting surface, a surface magnetic field integral equation (MFIE) is developed. Inside the volume of the coating region, volume MFIEs are applied. The resultant integral equations are solved using the moment method. Numerical results for the bistatic radar cross section for different structures are presented. The results are validated using the exact series solution for a conducting circular cylinder coated with multilayers of homogeneous materials. Two types of coating materials are studied: the conventional or double positive (DPS) materials and the double negative (DNG) materials.
Straggling in thin silicon detectors

Experimental and theoretical data for dielectric functions, x-ray absorption coefficients, and generalized oscillator strengths needed for a description of the energy-loss spectrum of fast charged particles in solid silicon are given. Theories used to calculate spectra of total energy loss ("straggling spectra") are described. The convolution method is used to calculate straggling functions for thin silicon absorbers. They are compared with those obtained from other theories (Landau). For relativistic particles ($\ensuremath{\gamma}g100$), the Vavilov-Shulek theories give incorrect functions for absorbers of thicknesses $tl1$ mm. The conversion of energy-loss spectra into ionization spectra is discussed, and the latter are compared with experimental functions. Good agreement is found between calculated and observed functions for electrons, mesons, protons, and their antiparticles and for $\ensuremath{\alpha}$ particles. From this agreement, the error ($1\ensuremath{\sigma}$) of the theoretical values of the most probable energy loss ${\ensuremath{\Delta}}_{p}$ and the full width at half maximum, $w$, is estimated to be less than \ifmmode\pm\else\textpm\fi{}1%.
Wide-field flexible endoscope for simultaneous color and NIR fluorescence image acquisition during surveillance colonoscopy

Colorectal cancer (CRC) is the third most common form of cancer and, despite recent declines in both incidence and mortality, it still remains the second leading cause of cancer-related deaths in the western world. Colonoscopy is the standard for detection and removal of premalignant lesions to prevent CRC. The major challenges that physicians face during surveillance colonoscopy are the high adenoma miss-rates and the lack of functional information to facilitate decision-making concerning which lesions to remove. Targeted imaging with NIR fluorescence would address these limitations. Tissue penetration is increased in the NIR range while the combination with targeted NIR fluorescent agents provides molecularly specific detection of cancer cells, i.e. a red-flag detection strategy that allows tumor imaging with optimal sensitivity and specificity. The development of a flexible endoscopic fluorescence imaging method that can be integrated with standard medical endoscopes and facilitates the clinical use of this potential is described in this work. A semi-disposable coherent fiber optic imaging bundle that is traditionally employed in the exploration of biliary and pancreatic ducts is proposed, since it is long and thin enough to be guided through the working channel of a traditional video colonoscope allowing visualization of proximal lesions in the colon. A custom developed zoom system magnifies the image of the proximal end of the imaging bundle to fill the dimensions of two cameras operating in parallel providing the simultaneous color and fluorescence video acquisition.
Characterization of Low-Power Wireless Links in UAV-Assisted Wireless-Sensor Network

The introduction of unmanned aerial vehicle (UAV) makes low-power links face many new challenges in UAV-assisted wireless-sensor network (WSN). In this article, the spatial characteristics of these low-power links are analyzed comprehensively, and the applicability of traditional link quality metrics and models is evaluated. In particular, the differences between link characteristics of UAV-assisted WSN and those of traditional WSN are discussed, and possible reasons for these differences are analyzed. To achieve this goal, two UAVs working on different bands are used and three different flight modes are designed. Experimental results show that link characteristics of UAV-assisted WSN become more complicated due to the 3-D movement of UAV. Link quality fluctuates significantly when the altitude or horizontal distance changes, and it is difficult to demarcate a clear bound between the connected and transitional region. Traditional models for spatial characteristic are only applicable when there is no UAV communication interference and the direction between the air node and ground node remains unchanged. Meanwhile, existing models between physical-layer metrics and packet reception ratio are only applicable when there is no UAV communication interference. For links with the same quality, stability of UAV-assisted WSN is not significantly different from that of traditional WSN. Finally, there is more obvious overall asymmetry between uplinks and downlinks in UAV-assisted WSN, and the quality of downlinks is significantly better than that of uplinks. The discovery of these new features would have great significance on the design of UAV-assisted WSN.
The rotation state of 67P/Churyumov-Gerasimenko from approach observations with the OSIRIS cameras on Rosetta

Aims: Approach observations with the Optical, Spectroscopic, and Infrared Remote Imaging System (OSIRIS) experiment onboard Rosetta are used to determine the rotation period, the direction of the spin axis, and the state of rotation of comet 67P's nucleus. Methods: Photometric time series of 67P have been acquired by OSIRIS since the post wake-up commissioning of the payload in March 2014. Fourier analysis and convex shape inversion methods have been applied to the Rosetta data as well to the available ground-based observations. Results: Evidence is found that the rotation rate of 67P has significantly changed near the time of its 2009 perihelion passage, probably due to sublimation-induced torque. We find that the sidereal rotation periods P1 = 12.76129 ± 0.00005 h and P2 = 12.4043 ± 0.0007 h for the apparitions before and after the 2009 perihelion, respectively, provide the best fit to the observations. No signs of multiple periodicity are found in the light curves down to the noise level, which implies that the comet is presently in a simple rotation state around its axis of largest moment of inertia. We derive a prograde rotation model with spin vector J2000 ecliptic coordinates λ = 65° ± 15°, β = + 59° ± 15°, corresponding to equatorial coordinates RA = 22°, Dec = + 76°. However, we find that the mirror solution, also prograde, at λ = 275° ± 15°, β = + 50° ± 15° (or RA = 274°, Dec = + 27°), is also possible at the same confidence level, due to the intrinsic ambiguity of the photometric problem for observations performed close to the ecliptic plane. Table 1 is available in electronic form at http://www.aanda. org