Miracle-dz/UniFAR-FTUs huggingface dataset:
Artefacts in multi-echo T2 imaging for high-precision gel dosimetry: III. Effects of temperature drift during scanning.

In high-precision 3D gel dosimetry, long MR measurement times together with a high amount of RF energy being absorbed by the phantom are very common, and result in a spatially dependent temperature rise in the gel. As T2 of the dosimeter gel is temperature dependent, dose estimation will be affected. In this study we assess the temperature rise in the dosimeter gel by use of MR temperature mapping and computer modelling. It is shown that in conventional MR sequences, where linear k-space sampling is used, a temperature rise of 3 °C results in a dose underestimation of 10% over the whole dose map. To correct for these dose errors, a compensation method involving centric k-space ordering is suggested. Computer simulations have been performed to analyse the robustness of the proposed method. Applying the compensated sequence, a temperature rise of 3 °C leads to a narrow dose artefact of the order of 3% for a 'worst case' situation in which a single pixel dose gradient is assumed. Negligible deviations are found in the rest of the dose map.
Simultaneously Modeling Joint and Marginal Distributions of Multivariate Categorical Responses

Abstract We discuss model-fitting methods for analyzing simultaneously the joint and marginal distributions of multivariate categorical responses. The models are members of a broad class of generalized logit and loglinear models. We fit them by improving a maximum likelihood algorithm that uses Lagrange's method of undetermined multipliers and a Newton-Raphson iterative scheme. We also discuss goodness-of-fit tests and adjusted residuals, and give asymptotic distributions of model parameter estimators. For this class of models, inferences are equivalent for Poisson and multinomial sampling assumptions. Simultaneous models for joint and marginal distributions may be useful in a variety of applications, including studies dealing with longitudinal data, multiple indicators in opinion research, cross-over designs, social mobility, and inter-rater agreement. The models are illustrated for one such application, using data from a recent General Social Survey regarding opinions about various types of government s.
Subpixel classifiers: fuzzy theory versus statistical learning algorithm

A comparative study between two approaches of subpixel classification, based on fuzzy set theory and statistical learning has been carried out. The fuzzy set classifiers investigated in this study are Fuzzy c-Means (FCM) and Possibilistic c-Means (PCM) in supervised modes. Further, Support Vector Machines (SVMs) have been used in this study for density estimation as a statistical learning subpixel classifier and Mean Field (MF) method has been used for easy and efficient learning procedure for the SVM. The three algorithms FCM, PCM and SVMs were evaluated in subpixel classification mode and accuracy assessment has been carried out using Fuzzy Error Matrix (FERM). Test on the two sub sets of LISS-III multi-spectral image from Resourcesat -1, (IRS-P6) satellite, indicates that density estimation based on SVM approach is consistent with different data sets and out performs both FCM as well as PCM approach.
Trapped modes in open channels

Trapped or edge-wave modes are well-known in linear water-wave theory. They occur at discrete frequencies below a certain cutoff frequency and consist of local oscillations trapped near a long horizontal submerged body in finite or infinite depth or over a sloping beach. Less well known is the existence of trapped modes in certain problems in acoustics where the governing equation is the Helmholtz equation. Jones (1953) has proved the existence of such modes which correspond to point-eigenvalues of the spectrum of the differential operator satisfying certain boundary conditions in a semi-infinite region. In this paper we describe a constructive method for determining point-eigenvalues or trapped-mode frequencies in two specific problems in which the two-imensional Helmholtz equation is satisfied. The problems arise from a consideration of the fluid motion in a long narrow wave tank with a free water surface which contains a vertical cylinder of uniform horizontal cross-section extending throughout the water depth. Separation of the depth dependence results in Helmholtz's equation with Neumann boundary conditions. By seeking solutions which are antisymmetric with respect to the centreline of the channel, trapped modes are constructed for the case of a cylinder of rectangular cross-section placed symmetrically in the centre of the channel and also for the case of a symmetric rectangular indentation in the tank walls. These problems do not appear to be covered directly by Jones’ theory and whilst the method described provides convincing numerical evidence, it falls short of a rigorous existence proof. Extensions to other purely acoustic problems having no water-wave interpretation, including problems which are covered by the general theory of Jones, are also discussed.
Introducing UWF-ZeekData22: A Comprehensive Network Traffic Dataset Based on the MITRE ATT&CK Framework

With the rapid rate at which networking technologies are changing, there is a need to regularly update network activity datasets to accurately reflect the current state of network infrastructure/traffic. The uniqueness of this work was that this was the first network dataset collected using Zeek and labelled using the MITRE ATT&CK framework. In addition to identifying attack traffic, the MITRE ATT&CK framework allows for the detection of adversary behavior leading to an attack. It can also be used to develop user profiles of groups intending to perform attacks. This paper also outlined how both the cyber range and hadoop’s big data platform were used for creating this network traffic data repository. The data was collected using Security Onion in two formats: Zeek and PCAPs. Mission logs, which contained the MITRE ATT&CK data, were used to label the network attack data. The data was transferred daily from the Security Onion virtual machine running on a cyber range to the big-data platform, Hadoop’s distributed file system. This dataset, UWF-ZeekData22, is publicly available at datasets.uwf. edu.
GeSn Vertical Heterostructure p-i-n Waveguide Light Emitting Diode for 2 μm Band Silicon Photonics

We demonstrate an electrically-injected GeSn <inline-formula> <tex-math notation="LaTeX">$\textit {p-i-n}$ </tex-math></inline-formula> waveguide light emitting diode on silicon, comprising a vertical Ge/GeSn/Ge double-barrier heterostructure for <inline-formula> <tex-math notation="LaTeX">$2 ~\mu \text{m}$ </tex-math></inline-formula> wavelength band integrated photonics. The incorporation of 4.2% Sn into the GeSn active layer results in bandgap shrinkage and extends the operating range to 2200 nm. Our design of the double-barrier heterostructure with the waveguide provides good carrier and optical confinement. The electroluminescence spectra at different current injection densities were measured at room temperature, demonstrating the peak wavelength at 1962 nm with the cutoff at 2200 nm, covering the entire <inline-formula> <tex-math notation="LaTeX">$2 ~\mu \text{m}$ </tex-math></inline-formula> wavelength band. The results show that the proposed vertical <inline-formula> <tex-math notation="LaTeX">$\textit {p-i-n}$ </tex-math></inline-formula> heterostructure GeSn diode opens a pathway to meeting the demand for group IV-based light sources required for <inline-formula> <tex-math notation="LaTeX">$2 ~\mu \text{m}$ </tex-math></inline-formula> wavelength band integrated photonics.
Global Existence for Nonlinear Hyperbolic Systems of Kirchhoff Type

Abstract In this paper we prove the global solvability of the Cauchy problem, with small and suitably smooth initial data, for nonlinear hyperbolic systems with integro- differential coefficients of Kirchhoff type. This extends to a wide class of nonlinear hyperbolic equations some results in [4, 5, 7] and [10]. Our method is similar to the technique employed by Greenberg & Hu in [10] in the case of the classical Kirchhoff equation.
A Predictive Model of Different Temperature Growth of Escherichia Coli in Fresh-cut Lettuce Based on Matlab7.0

Contamination of Escherichia coli in fresh-cut lettuce poses potential risk to the public. In order to study the growth characteristics of Escherichia coli 1.1187, we established a prediction model of different temperature growth of Escherichia coli in fresh-cut lettuce based on Matlab7.0. In this study, the prediction model can well forecast the dynamic growth of Escherichia coli 1.1187 in fresh-cut lettuce, and it provides a rapid and effective method for safety assessment of fresh-cut lettuce during storage. The growth state of Escherichia coli 1.1187 was analyzed at different temperatures (4°C, 11°C, 19°C, 27°C and 35°C). The primary prediction model was established by modified the Gompertz equation. The secondary prediction model was established by square root equation. Then the model was verified at different temperatures (22°C and 30°C). Experimental results showed that the primary prediction model fitting correlation coefficient is above 0.99, the bias factor and accuracy factor of secondary model are in the range of 0.90 and 1.05. At 4°C, Escherichia coli 1.1187 growth was restrained dramatically, so it is impossible for fitting by modified the Gompertz equation. In this study, we obtained the low growth temperature and the optimum growth temperature of E.coli 1.1187 were 7.03°C and 17.52°C respectively. Keywords-predictive model; escherichia coli; fresh-cut Lettuce; Matlab7.0.
Wavelet-based blind watermark retrieval technique

A wavelet-based watermark casting scheme and a blind watermark retrieval technique are investigated in this research. An adaptive watermark hiding method is first developed to determine significant wavelet subbands and to select a couple of significant wavelet coefficients in these subbands automatically. Then, a blind watermark retrieval technique that can detect the embedded watermark in the wavelet domain without the help from the original image is proposed. Experimental results show that the embedded images's watermark can be retrieved successfully without the original image even after the JPEG compression with a quality factor of 20 percent and the wavelet based compression attack with the 64 to 1 compression ratio. With the help of original image, the watermark can be detected after more serious attacks.
Quantifying the robustness of fuzzy rule sets in object-based image analysis

Object-based image analysis (OBIA) has become very popular since the turn of the century. For high-resolution situations, in particular, where the objects of interest are larger than pixels, methods have been developed that build on image segmentation and on the further classification of objects rather than on pixels. Many studies have shown that OBIA methods are, in principle, more transferable and reapplicable to other images. To obtain comparable results by reapplying a given rule set on (slightly) changed conditions, the rule set must either be able to adapt to the changed conditions or it must be parameterized for manual adaptation. In this context, a rule set can be seen as the more robust the less it has to be changed, and vice versa. In this article we introduce a new method to evaluate the robustness of a rule set. The main assumption is that the amount of necessary adaptations can be measured in conjunction with the quality of classification achieved. We demonstrate that the method introduced is able to (1) evaluate the robustness of a rule set and (2) identify crucial elements of a rule set that need to be reparameterized.
Lightweight Per-Flow Traffic Measurement Using Improved LRU List

Per-flow traffic measurement is extremely important for various applications, e.g., flow size distribution, flow cardinality and DDos detection. Previous works, e.g., Elastic Sketch and FlowRadar, incur massive per-packet processing overhead and/or large memory consumption. In this paper, we present a novel least-recently-used (LRU) list based solution, called LRU-TX, for lightweight and accurate per-flow traffic measurement. Different from the classic LRU list with one exit at the tail, we maintain another exit at a certain position <inline-formula><tex-math notation="LaTeX">$r$</tex-math></inline-formula> (not the tail) in the list. Many terminated flows will be removed from the exit at position <inline-formula><tex-math notation="LaTeX">$r$</tex-math></inline-formula> as soon as possible with their counters less than a given threshold, which helps to decrease both the amortized processing overhead and the memory consumption. We also formally analyze the impact of different parameters (e.g., the exit's position, the threshold) on the measurement performance. Experimental results and extensive simulation results show that LRU-TX can increase the throughput by 30% at least, and reduce the memory cost by 50%, compared with the state-of-the-art solutions under the same measurement error conditions.
The optical synthetic aperture image restoration based on the improved maximum-likelihood algorithm

Optical synthetic aperture imaging (OSAI) can be envisaged in the future for improving the image resolution from high altitude orbits. Several future projects are based on optical synthetic aperture for science or earth observation. Comparing with equivalent monolithic telescopes, however, the partly filled aperture of OSAI induces the attenuation of the modulation transfer function of the system. Consequently, images acquired by OSAI instrument have to be post-processed to restore ones equivalent in resolution to that of a single filled aperture. The maximum-likelihood (ML) algorithm proposed by Benvenuto performed better than traditional Wiener filter did, but it didn't work stably and the point spread function (PSF), was assumed to be known and unchanged in iterative restoration. In fact, the PSF is unknown in most cases, and its estimation was expected to be updated alternatively in optimization. Facing these limitations of this method, an improved ML (IML) reconstruction algorithm was proposed in this paper, which incorporated PSF estimation by means of parameter identification into ML, and updated the PSF successively during iteration. Accordingly, the IML algorithm converged stably and reached better results. Experiment results showed that the proposed algorithm performed much better than ML did in peak signal to noise ratio, mean square error and the average contrast evaluation indexes.
Wavelength-angle selectivity of an angled grating in a Fabry-Perot resonator (alpha-laser)

This paper presents an analytical treatment of the filtering properties of an angled Bragg grating embedded in a Fabry-Perot interferometer as used for -lasers. The wave propagation is connected with a double codirectional Bragg reflection including a quenching of the zero-order diffraction. The angular and spectral selectivity are discussed for different system parameters.
Solid‐phase microextraction and cuticular hydrocarbon differences related to reproductive activity in juniper bark borer Semanotus bifasciatus Motschulsky

Cuticular hydrocarbons of Cerambycidae species can function as signals for sex recognition. Little is known about the copulatory signals of the juniper bark borer Semanotus bifasciatus, a major economic threat to Platycladus orientalis Franco in China. Here, we investigated the cuticular hydrocarbons of both sexes of S. bifasciatus to determine the chemically mediated mating signals using the solid‐phase microextraction (SPME) technique with carbowax/divinylbenzene fibers (CAR/DVB) and then analyzed by coupled gas chromatography‐mass spectrometry (GC‐MS). A series of aliphatic saturated straight‐chain n‐alkanes (n‐C23 to n‐C28), internally branched monomethylalkanes at carbons 3, 11, or 13, and dimethylalkanes were identified, which showed no qualitative differences in either sex and were similar in the samples with SPME fiber extraction and those with hexane extraction. The bioassay showed that 11‐methylpentacosane (11‐MeC25), 11‐methylhexacosane (11‐MeC26), and 11‐methylheptacosane (11‐MeC27) have sex‐specific recognition functions that triggered more mating attempts at a female‐specific ratio of 100:4:60 than at a male‐specific ratio of 100:85:50. In addition, the female‐specific ratio of 11‐methylalkanes can elicit about 70% of male mating attempts within about 60 s, whereas live females elicit about 98% of male mating attempts within 25 s. The discrepancy in the initiation of mating attempts by synthetic mixtures and live females suggests that the methyl isomers 3‐MeC25, 3‐MeC27, and/or 11,15‐diMeC27 may also be involved in the mating behavior of S. bifasciatus. These results suggest that 11‐MeC25, 11‐MeC26, and 11‐MeC27 constitute the contact sex pheromone of S. bifasciatus, with the presence or absence of 11‐MeC26 in particular playing an important role in mate recognition by males.
Blocking Rate Analysis in Heterogeneous Multicell Cognitive-Radio 5G Networks

Cognitive radio (CR) technology is being recognized as one of the main enabling technologies for supporting massive high-speed connectivity in multicell fifth-generation (5G) networks by allowing dynamic spectrum access policies according to predetermined etiquette. Under this paradigm, the available spectrum is opportunistically allocated to the different cells. A key metric that is heavily employed in designing efficient CR-based multicell spectrum-allocation mechanisms is the blocking rate. An efficient spectrum-allocation mechanism aims to adaptively allocate channels to the different cells such that the overall blocking rate is minimized. In this article, we use the theory of continuous-time Markov chains to derive a closed-form expression for the blocking rate in multicell CR-based 5G networks. In our derivations, we build two detailed mathematical models describing the frequency-spectrum usage of both primary and secondary users. We combine the two models in a hierarchical fashion. As opposed to related models in the literature which suffer high complexity, the proposed hierarchical structure yields simplicity and tractability. Furthermore, while existing research works overlook spectrum heterogeneity, the proposed model addresses this important factor. Simulation results demonstrate high accuracy in evaluating the blocking rate across the different cells in the network.
Plasma energy and work function of conducting transition metal nitrides for electronic applications

The combination of electrical conductivity, chemical and metallurgical stability, refractory character, having lattice constants that are close to those of III-nitrides makes transition metal nitrides promising candidates for electronics and device applications. We study the structure, stability, and the plasma energy of stoichiometric, transition metal nitrides of similar crystal quality as well as the widest variety of their ternaries ever reported. We establish the phase spaces of the plasma energy (6.9–10.5 eV) and the work function (3.7–5.1 eV) of these complex nitrides with their lattice constant (0.416–0.469 nm) and we investigate the limits of their applications.
Sensitivity enhancement of FBG temperature sensor

We used a bimetallic strip to increase the sensitivity of a fiber Bragg grating temperature sensor. The temperatureinduced deflection of the strip strained the FBG sensor, increasing the Bragg wavelength shift in addition to the temperature-induced one. The total Bragg wavelength shift is about 4 times larger than that of the intrinsic FBG temperature sensor. With experiments in various conditions, the sensitivity characteristics according to the bimetal parameters were analyzed and the feasibility of the suggested sensor has been shown
The possibility of gallium oxide (β-Ga2O3) heterojunction bipolar transistors

Bipolar junction transistors have not been viable with β-Ga2O3 due to its poor hole mobility and unavailability of shallow acceptors. Many p-type oxides form high-quality heterojunction diodes (low ideality factor and high breakdown voltage) with β-Ga2O3. We propose using these heterojunctions to make a β-Ga2O3 heterojunction bipolar transistor (HBT). Cu2O/β-Ga2O3 heterojunction is especially promising because of the relatively high electron diffusion length (∼μ m) in Cu2O, a low electron injection barrier at the Cu2O-Ga2O3 interface, and breakdown voltages of >1000 V. Using Silvaco TCAD, we simulate a β-Ga2O3 heterojunction bipolar transistor with a Cu2O base and estimate the power figure of merit (PFOM). We find that the low bandgap of Cu2O severely limits the performance of these HBTs. Reports of Cu2O-Ga2O3 diodes with extremely high breakdown voltage are probably due to heavily doped Cu2O or interface defects, but these effects do not translate to the HBT. For HBTs with PFOM better than the state-of-the-art β-Ga2O3 unipolar transistors, we need alternative p-type oxides with a bandgap E g > 3.4 eV and electron diffusion length >0.4 μ m. We discuss the possible candidates. Using an empirical model for the critical avalanche breakdown field, we estimate the maximum PFOM for possible β-Ga2O3 HBTs.
Sustainable Strategies to Counteract Mycotoxins Contamination and Cowpea Weevil in Chickpea Seeds during Post-Harvest

Mycotoxins contamination and pest infestation of foods and feeds represent a pivotal threat for food safety and security worldwide, with crucial implications for human and animal health. Controlled atmosphere could be a sustainable strategy to reduce mycotoxins content and counteract the vitality of deleterious organisms in foodstuff. Ozone treatment (O3, 500 ppb for 30, 60 or 90 min) and high nitrogen concentration (N2, 99% for 21 consecutive days) were tested in the post-harvest management of four batches of Cicer arietinum grains to control the presence of mycotoxigenic fungi and their secondary metabolites, as well as pest (i.e., Callosobruchus maculatus) infestation. At the end of the treatment, O3 significantly decreased the incidence of Penicillium spp. (by an average of −50%, independently to the time of exposure) and reduced the patulin and aflatoxins content after 30 min (−85 and −100%, respectively). High N2 concentrations remarkably reduced mycotoxins contamination (by an average of −94%) and induced pest mortality (at 100% after 5 days of exposure). These results confirm the promising potential of O3 and N2 in post-harvest conservation strategies, leading to further investigations to evaluate the effects on the qualitative characteristics of grains.