bluuebunny/crossref_metadata_2025 huggingface dataset:
A Wideband Cryogenic Readout Amplifier with Temperature-Insensitive Gain for SNSPD
Authors: Niu Xiaokang , Li Lianming , Wu Xu , Wang Dongming
Published: February 2022

This paper presents a temperature-insensitive wideband cryogenic amplifier for superconducting nanowire single-photon detectors (SNSPD). With a proposed folded diode-connected transistor load to realize a good device-tracking feature, the theoretical derivations the simulations and test results prove that the amplifier-gain cell has a stable gain performance over a wide temperature range, solving the issues of a lack of the accurate cryogenic device models. The amplifier achieves a gain of 26 dB from 100 kHz to 1 GHz at 4.2 K, consuming only 1.8 mW from a 1.8 V supply. With a 0.13-μm SiGe BiCMOS process, the chip area is 0.5 mm².
Quantitative Detection of Extra Virgin Olive Oil Adulteration, as Opposed to Peanut and Soybean Oil, Employing LED-Induced Fluorescence Spectroscopy
Authors: Zhang Ting , Liu Yuyang , Dai Zhuoping , Cui Lihan , Lin Hongze , Li Zejian , Wu Kaihua , Liu Guangyu
Published: February 2022

As it is high in value, extra virgin olive oil (EVOO) is frequently blended with inferior vegetable oils. This study presents an optical method for determining the adulteration level of EVOO with soybean oil as well as peanut oil using LED-induced fluorescence spectroscopy. Eight LEDs with central wavelengths from ultra-violet (UV) to blue are tested to induce the fluorescence spectra of EVOO, peanut oil, and soybean oil, and the UV LED of 372 nm is selected for further detection. Samples are prepared by mixing olive oil with different volume fractions of peanut or soybean oil, and their fluorescence spectra are collected. Different pre-processing and regression methods are utilized to build the prediction model, and good linearity is obtained between the predicted and actual adulteration concentration. This result, accompanied by the non-destruction and no pre-treatment characteristics, proves that it is feasible to use LED-induced fluorescence spectroscopy as a way to investigate the EVOO adulteration level, and paves the way for building a hand-hold device that can be applied to real market conditions in the future.
An Experimental Study on Combustion and Cycle-by-Cycle Variations of an N-Butanol Engine with Hydrogen Direct Injection under Lean Burn Conditions
Authors: Shang Weiwei , Yu Xiumin , Shi Weibo , Chen Zhao , Liu Huiying , Yu He , Xing Xiaoxue , Xu Tingfa
Published: February 2022

This study experimentally investigated the effects of hydrogen direct injection on combustion and the cycle-by-cycle variations in a spark ignition n-butanol engine under lean burn conditions. For this purpose, a spark ignition engine installed with a hydrogen and n-butanol dual fuel injection system was specially developed. Experiments were conducted at four excess air ratios, four hydrogen fractions(φ(𝐻2)) and pure n-butanol. Engine speed and intake manifold absolute pressure (MAP) were kept at 1500 r/min and 43 kPa, respectively. The results indicate that the θ0–10 and θ10–90 decreased gradually with the increase in hydrogen fraction. Additionally, the indicated mean effective pressure (IMEP), the peak cylinder pressure (Pmax) and the maximum rate of pressure rise ((dP/dφ)max) increased gradually, while their cycle-by-cycle variations decreased with the increase in hydrogen fraction. In addition, the correlation between the (dP/dφ)max and its corresponding crank angle became weak with the increase in the excess air coefficient (λ), which tends to be strongly correlated with the increase in hydrogen fraction. The coefficient of variation of the Pmax and the IMEP increased with the increase in λ, while they decreased obviously after blending in the hydrogen under lean burn conditions. Furthermore, when λ was 1.0, a 5% hydrogen fraction improved the cycle-by-cycle variations most significantly. While a larger hydrogen fraction is needed to achieve the excellent combustion characteristics under lean burn conditions, hydrogen direct injection can promote combustion process and is beneficial for enhancing stable combustion and reducing the cycle-by-cycle variations.
Investigation on Sensing Performance of Highly Doped Sb/SnO2
Authors: Feng Zhifu , Gaiardo Andrea , Valt Matteo , Fabbri Barbara , Casotti Davide , Krik Soufiane , Vanzetti Lia , Ciana Michele Della , Fioravanti Simona , Caramori Stefano , Rota Alberto , Guidi Vincenzo
Published: February 2022

Tin dioxide (SnO2) is the most-used semiconductor for gas sensing applications. However, lack of selectivity and humidity influence limit its potential usage. Antimony (Sb) doped SnO2 showed unique electrical and chemical properties, since the introduction of Sb ions leads to the creation of a new shallow band level and of oxygen vacancies acting as donors in SnO2. Although low-doped SnO2:Sb demonstrated an improvement of the sensing performance compared to pure SnO2, there is a lack of investigation on this material. To fill this gap, we focused this work on the study of gas sensing properties of highly doped SnO2:Sb. Morphology, crystal structure and elemental composition were characterized, highlighting that Sb doping hinders SnO2 grain growth and decreases crystallinity slightly, while lattice parameters expand after the introduction of Sb ions into the SnO2 crystal. XRF and EDS confirmed the high purity of the SnO2:Sb powders, and XPS highlighted a higher Sb concentration compared to XRF and EDS results, due to a partial Sb segregation on superficial layers of Sb/SnO2. Then, the samples were exposed to different gases, highlighting a high selectivity to NO2 with a good sensitivity and a limited influence of humidity. Lastly, an interpretation of the sensing mechanism vs. NO2 was proposed.
Coexistence of Satellite Ground Stations in Teleport Facilities: Interference Assessment, Real Application Scenario and Measurements
Authors: Moraitis Nektarios , Panagopoulos Athanasios D.
Published: February 2022

This article introduces a unified and detailed methodology for interference assessment between coexisting fixed satellite service (FSS) and broadcast satellite service (BSS) with spectrum sharing at the Ka-band. The interference analysis is presented along with a step-by-step algorithm for the calculation of the carrier-to-interference ratio (CIR). The proposed procedure takes into consideration the near-field effect of ground-satellite-terminal antennas since these may reside at very close distances. Furthermore, numerical results are delivered so as to assess the CIR in relation to the relative geometry and the technical characteristics of the satellite terminals. A real application scenario is also provided along with measurements so as to validate the recommended methodology. Finally, mitigation techniques are proposed for the protection of the victim stations and operation under harmful interference conditions.
A Low-Power High-Accuracy Urban Waterlogging Depth Sensor Based on Millimeter-Wave FMCW Radar
Authors: Shui Hanyue , Geng Haoran , Li Qiong , Du Li , Du Yuan
Published: February 2022

The method of making precise measurements of remote water depth using mmWave technology has great potential for preventing urban waterlogging. To achieve waterlogging prevention, the mmWave system needs to measure the water depth change accurately with a short acquisition time. This paper demonstrates a new accurate mmWave water depth measurement system based on Frequency Modulated Continuous Wave (FMCW) Radar with a center frequency of 77 GHz. To improve distance resolution and lower acquisition time, the Swept Frequency-Cross Correlation (SFCC) algorithm is proposed for the first time to improve the distance computation resolution by 9× and lower time complexity from O(n·logn) to O(n) compared to traditional FFT-based FMCW radar distance computation. A prototype system equipped with a humidity sensor, a processor module and TI’s FMCW radar module is designed for monitoring urban floods in cities. Using the prototype system with the proposed SFCC, the depth measurement error is reduced from 4.5 cm to less than 5 mm, compared to the default radar post-processing algorithm embedded in the radar module.
Breath Analysis: A Promising Tool for Disease Diagnosis—The Role of Sensors
Authors: Kaloumenou Maria , Skotadis Evangelos , Lagopati Nefeli , Efstathopoulos Efstathios , Tsoukalas Dimitris
Published: February 2022

Early-stage disease diagnosis is of particular importance for effective patient identification as well as their treatment. Lack of patient compliance for the existing diagnostic methods, however, limits prompt diagnosis, rendering the development of non-invasive diagnostic tools mandatory. One of the most promising non-invasive diagnostic methods that has also attracted great research interest during the last years is breath analysis; the method detects gas-analytes such as exhaled volatile organic compounds (VOCs) and inorganic gases that are considered to be important biomarkers for various disease-types. The diagnostic ability of gas-pattern detection using analytical techniques and especially sensors has been widely discussed in the literature; however, the incorporation of novel nanomaterials in sensor-development has also proved to enhance sensor performance, for both selective and cross-reactive applications. The aim of the first part of this review is to provide an up-to-date overview of the main categories of sensors studied for disease diagnosis applications via the detection of exhaled gas-analytes and to highlight the role of nanomaterials. The second and most novel part of this review concentrates on the remarkable applicability of breath analysis in differential diagnosis, phenotyping, and the staging of several disease-types, which are currently amongst the most pressing challenges in the field.
Antioxidant Activity, Sun Protection Activity, and Phytochemical Profile of Ethanolic Extracts of Daemonorops acehensis Resin and Its Phytosomes
Authors: Sari Rita Kartika , Prayogo Yanico Hadi , Rozan Salman Arib , Rafi Mohamad , Wientarsih Ietje
Published: February 2022

Daemonorops (Indonesian: jernang) resin is one of Indonesia’s leading non-timber forest products and can be developed as a source of natural antioxidants and sun protection. This study aimed to select promising solvents for extracting a Daemonorops acehensis resin and phytosome formulation with high antioxidant capacities and sun protection factor (SPF) values. Jernang resin was extracted using a water–ethanol mixture in five different ratios. The promising extract was then mixed with soy lecithin in three different formulations. A promising extract and phytosome were then selected based on their antioxidant capacities and sun protection factor (SPF) values. A liquid chromatography mass spectrometry/mass spectrometry (LC–MS/MS) analysis was also performed on five extracts to identify the components in the extracts that might be responsible for the biological activity. The results showed that the ethanol solvent variation and phytosome formulation influenced the antioxidant capacity and SPF value. A hundred-percent ethanolic extract and F1 phytosome exhibited the highest antioxidant capacities and SPF values. A qualitative analysis revealed the various classes of compounds in the extract and phytosome. A flavylium chromophore, dracorhodin, dominated the resin extract and was presumed to be the marker compound responsible for their antioxidant capabilities and SPF values. These findings are important for manufacturing sunscreens containing active compounds of bioactive natural resins.
A Complete Heterogeneous Model for the Production of n-Propyl Propionate Using a Simulated Moving Bed Reactor
Authors: Santos Rodrigo , Rebello Carine , Prudente Anderson , Ribeiro Ana M. , Rodrigues Alírio E. , Loureiro José M. , Pontes Karen V. , Nogueira Idelfonso B. R.
Published: February 2022

n-Propyl Propionate (ProPro) is a harmless biodegradable product employed in several fields for the production of drugs, inks, coating, food, and perfume. ProPro is synthesized in an equilibrium reaction for which its yield can be enhanced by constant withdraw of the products as the reaction takes place. Simulated Moving Bed Reactor (SMBR) is a candidate for the production of ProPro with high efficiency as it is a multifunction unit able to simultaneously run reaction and separation, hence shifting the equilibrium reaction toward products. This paper proposes a complete phenomenological model for the ProPro synthesis in a Simulated Moving Bed Reactor (SMBR) packed with the heterogeneous catalyst Amberlyst 46 resin. The operating conditions are defined by the Triangle Theory to design an SMBR unit to produce ProPro efficiently and a comprehensive parameter estimation procedure is employed to obtain more representative parameters. The validated phenomenological model was applied to design an SMBR unit to produce high purity (99.28%) ProPro.
Sexual and Reproductive Health Service Provision to Adolescents in Edmonton: A Qualitative Descriptive Study of Adolescents’ and Service Providers’ Experiences
Authors: Vass Eliza , Bhanji Zia , Adewale Bisi , Meherali Salima
Published: February 2022

The goal of adolescent sexual reproductive health (SRH) services is to provide information, education and healthcare to promote safe health practices and protect adolescents from negative health outcomes; however, access to timely, effective, and affordable SRH services by adolescents in Edmonton, Canada remains relatively unknown. Our study sought to understand the perspectives and experiences of adolescent girls and service providers in relation to availability, accessibility, and quality of SRH services available in Edmonton. The study objectives were to explore SRH services adolescents seek, uncover barriers in accessing SRH services and identify areas to improve accessibility. Qualitative description design was employed to conduct this study. Five service providers specializing in SRH, and eight females (ages 17–20 years) that access SRH services were recruited from the Alberta Health Services Birth Control Centre (BCC). Semi-structured interviews took place via Zoom. Thematic analysis was conducted using NVIVO software. Findings consisted of four primary themes: (1) views and current SRH practices; (2) barriers to accessibility; (3) the effects of COVID-19 on accessibility; (4) identified gaps in SRH care. The findings from our study support the development of knowledge translation strategies and make recommendations to improve the present quality of SRH services in Edmonton.
Do Pornography Use and Masturbation Frequency Play a Role in Delayed/Inhibited Ejaculation during Partnered Sex? A Comprehensive and Detailed Analysis
Authors: Rowland David L. , Morrow Abigail L. , Hamilton Benjamin D. , Hevesi Krisztina
Published: February 2022

The role of masturbation frequency and pornography use on sexual response during partnered sex has been controversial, the result of mixed and inconsistent findings. However, studies investigating this relationship have often suffered from methodological shortcomings. We investigated the role of masturbation frequency and pornography use on both the occurrence and severity of delayed/inhibited ejaculation (DE), an increasingly common sexual problem among men. We did so in a large (nonclinical) multinational sample of cisgender men (N = 2332; mean age = 40.3, SE = 0.31) within a multivariate context that relied on multiple (and, when possible, standardized) assessments of sexual dysfunctions while controlling for possible confounding variables. Results indicated a weak, inconsistent, and sometimes absent association between the frequency of pornography use and DE symptomology and/or severity. In contrast, both poorer erectile functioning and anxiety/depression represented consistent and strong predictors of DE and, to a lesser extent, DE severity. Other factors, including relationship satisfaction, sexual interest, and masturbation frequency, were significantly though moderately to weakly associated with DE. In conclusion, associations (or sometimes lack thereof) between masturbation frequency, pornography use, and delayed ejaculation are more clearly understood when analyzed in a multivariate context that controls for possible confounding effects.
Continuous Adaptation with Online Meta-Learning for Non-Stationary Target Regression Tasks
Authors: Yamagata Taku , Santos-Rodríguez Raúl , Flach Peter
Published: February 2022

Most environments change over time. Being able to adapt to such non-stationary environments is vital for real-world applications of many machine learning algorithms. In this work, we propose CORAL, a computationally efficient regression algorithm capable of adapting to a non-stationary target. CORAL is based on Bayesian linear regression with a sliding window and offline/online meta-learning. The sliding window makes our model focus on the recently received data and ignores older observations. The meta-learning approach allows us to learn the prior distribution of the model parameters. It speeds up the model adaptation, complements the sliding window’s drawback, and enhances the performance. We evaluate CORAL on two tasks: a toy problem and a more complex blood glucose level prediction task. Our approach improves the prediction accuracy for the non-stationary target significantly while also performing well for the stationary target. We show that the two components of our method work in a complementary fashion to achieve this.
Accuracy and Error Trends of Commercially Available Bat Swing Sensors in Baseball
Authors: Morishita Yoshitaka , Jinji Tsutomu
Published: February 2022

In baseball, the swing speed and swing angle of the bat just before ball impact are important to increase the speed and horizontal distance of a batted ball. This study investigated the accuracies and error trends of four commercially available bat sensors to measure these parameters. The hitting motions of seven healthy participants were measured simultaneously using the bat sensors and an optical motion capture system, and the swing speeds and swing angles were compared. The swing speed was measured with high accuracy, as indicated by the high intraclass correlation coefficient (ICC) between the bat sensor and the motion capture system measurements (mean ICC = 0.78). However, the ICC for the swing angle was lower (mean ICC = 0.58) than that of the swing speed for all but one bat sensor, indicating low accuracy. Moreover, in the high swing speed range, the accuracy of the swing speed tended to decrease for three bat sensors, but the trend of the swing angle was different among bat sensors. Significant systematic biases or proportional errors were found for all bat sensors, indicating the possibility of error correction. The sensor used in this study can help to evaluate the differences between players with different competition levels and hitting motions. Coaches need to be cautious in taking measurements of players with high swing speeds and in assessing slight changes within an individual.
On Generalization of Different Integral Inequalities for Harmonically Convex Functions
Authors: Reunsumrit Jiraporn , Vivas-Cortez Miguel J. , Ali Muhammad Aamir , Sitthiwirattham Thanin
Published: February 2022

In this study, we first prove a parameterized integral identity involving differentiable functions. Then, for differentiable harmonically convex functions, we use this result to establish some new inequalities of a midpoint type, trapezoidal type, and Simpson type. Analytic inequalities of this type, as well as the approaches for solving them, have applications in a variety of domains where symmetry is important. Finally, several particular cases of recently discovered results are discussed, as well as applications to the special means of real numbers.
Compressive Strength Characteristics of Long Tubular Bones after Hyperthermal Ablation
Authors: Pakhmurin Denis , Pakhmurina Viktoriya , Kashin Alexander , Kulkov Alexey , Khlusov Igor , Kostyuchenko Evgeny , Sidorov Ivan , Anisenya Ilya
Published: February 2022

Thermoablation is used in the treatment of tumorous bones. However, little is known about the influence such thermal treatment has on the mechanical properties of bone tissue. The purpose of this work was to study the influence of thermal treatment in a range of 60–100 °C (in increments of 10 °C) on the structural properties of pig femurs using an original approach that involved a periosteal arrangement of heating elements providing gradual dry heating of the bone from its periphery to its center. Heating of freshly extracted bone tissue segments was performed ex vivo using surface heaters of a Phoenix-2 local hyperthermia hardware system. Mechanical testing followed the single-axis compression scheme (traverse velocity of 1 mm/min). In the 60–90 °C range of heating, no attributes of reduced structural characteristics were found in the samples subjected to thermoablation in comparison to the control samples taken from symmetric areas of adjacent cylinders of healthy bones and not subjected to heat treatment. The following statistically significant changes were found as a result of compressing the samples to 100 °C after the heat treatment: reduced modulus of elasticity and increased elastic strain (strain-to-failure), mainly due to increases in plastic deformation. This finding may serve as evidence of a critical ex vivo change in the biomechanical behavior of bone tissues at such temperatures. Thus, ex vivo treatment of bone tissue in the thermal range of 60–90 °C may be used in studies of thermoablation efficiency against tumor involvement of bones.
Super Vertex (Edge)-Connectivity of Varietal Hypercube
Authors: Yu Zhecheng , Xu Liqiong , Yin Shanshan , Guo Litao
Published: February 2022

The reliability measure of networks is of significant importance to the design and maintenance of networks. Based on connectivity, many refined quantitative indicators for the reliability of network systems have been introduced. The super vertex edge-connectivity and cyclic edge-connectivity, as important parameters to evaluate the robustness of networks, are explored extensively. As a variant of the hypercube Qn, the varietal hypercube VQn has better properties than Qn with the same number of edges and vertices. Wang and Xu have proved that VQn is super vertex-connected for n≥1 and is also super edge-connected if n≠2. In this paper, we use another method to prove these results. Moreover, we also obtain the super restricted connectivity and the cyclic edge-connectivity of the varietal hypercube VQn.
TCAN-IDS: Intrusion Detection System for Internet of Vehicle Using Temporal Convolutional Attention Network
Authors: Cheng Pengzhou , Xu Kai , Li Simin , Han Mu
Published: February 2022

Intrusion detection systems based on recurrent neural network (RNN) have been considered as one of the effective methods to detect time-series data of in-vehicle networks. However, building a model for each arbitration bit is not only complex in structure but also has high computational overhead. Convolutional neural network (CNN) has always performed excellently in processing images, but they have recently shown great performance in learning features of normal and attack traffic by constructing message matrices in such a manner as to achieve real-time monitoring but suffer from the problem of temporal relationships in context and inadequate feature representation in key regions. Therefore, this paper proposes a temporal convolutional network with global attention to construct an in-vehicle network intrusion detection model, called TCAN-IDS. Specifically, the TCAN-IDS model continuously encodes 19-bit features consisting of an arbitration bit and data field of the original message into a message matrix, which is symmetric to messages recalling a historical moment. Thereafter, the feature extraction model extracts its spatial-temporal detail features. Notably, global attention enables global critical region attention based on channel and spatial feature coefficients, thus ignoring unimportant byte changes. Finally, anomalous traffic is monitored by a two-class classification component. Experiments show that TCAN-IDS demonstrates high detection performance on publicly known attack datasets and is able to accomplish real-time monitoring. In particular, it is anticipated to provide a high level of symmetry between information security and illegal intrusion.
Dynamic Characteristics of a Beam with a Shallow Crack Using Alternative Admissible Functions
Authors: Kateel Srividyadhare , Baddour Natalie
Published: February 2022

The presence of a crack in a beam leads to changes in its dynamic characteristics and hence changes in its natural frequencies and mode shapes. In this paper, Alternative Admissible Functions (AAF) with penalties for extracting the dynamic characteristics of a Euler–Bernoulli Beam with a shallow crack is proposed and validated. The proposed method has two key advantages. First, the alternative admissible function choice is independent of the boundary conditions, which are modelled via boundary penalty terms. Second, the crack is treated as a penalty function to account for the local stiffness reduction while ensuring beam continuity. The approach is validated with different crack depth ratios and locations. The mass, stiffness, and penalty function matrices for Simply Supported (SS), Clamped–Clamped (CC), and Clamped–Free (CF) are developed and are used in the analysis of a beam with a shallow crack. The proposed method demonstrates results in good agreement with published literature for shallow cracks. A significant advantage of the proposed method is the ease of applicability, eliminating the need for remodeling with changes in boundary conditions or crack parameters. The results show that the crack introduces asymmetry to the beam and may require changing the boundary penalty values, depending on the location and depth of the crack.
Some Fuzzy Riemann–Liouville Fractional Integral Inequalities for Preinvex Fuzzy Interval-Valued Functions
Authors: Khan Muhammad Bilal , Zaini Hatim Ghazi , Macías-Díaz Jorge E. , Treanțǎ Savin , Soliman Mohamed S.
Published: February 2022

The main objective of this study is to introduce new versions of fractional integral inequalities in fuzzy fractional calculus utilizing the introduced preinvexity. Due to the behavior of its definition, the idea of preinvexity plays a significant role in the subject of inequalities. The concepts of preinvexity and symmetry have a tight connection thanks to the significant correlation that has developed between both in recent years. In this study, we attain the Hermite-Hadamard (H·H) and Hermite-Hadamard-Fejér (H·H Fejér) type inequalities for preinvex fuzzy-interval-valued functions (preinvex F·I·V·Fs) via Condition C and fuzzy Riemann–Liouville fractional integrals. Furthermore, we establish some refinements of fuzzy fractional H·H type inequality. There are also some specific examples of the reported results for various preinvex functions deduced. To support the newly introduced ideal, we have provided some nontrivial and logical examples. The results presented in this research are a significant improvement over earlier results. This paper’s awe-inspiring notions and formidable tools may energize and revitalize future research on this worthwhile and fascinating topic.
Exact Time-Dependent Solutions and Information Geometry of a Rocking Ratchet
Authors: Kim Eun-jin , Hollerbach Rainer
Published: February 2022

The noise-induced transport due to spatial symmetry-breaking is a key mechanism for the generation of a uni-directional motion by a Brownian motor. By utilising an asymmetric sawtooth periodic potential and three different types of periodic forcing G(t) (sinusoidal, square and sawtooth waves) with period T and amplitude A, we investigate the performance (energetics, mean current, Stokes efficiency) of a rocking ratchet in light of thermodynamic quantities (entropy production) and the path-dependent information geometric measures. For each G(t), we calculate exact time-dependent probability density functions under different conditions by varying T, A and the strength of the stochastic noise D in an unprecedentedly wide range. Overall similar behaviours are found for different cases of G(t). In particular, in all cases, the current, Stokes efficiency and the information rate normalised by A and D exhibit one or multiple local maxima and minima as A increases. However, the dependence of the current and Stokes efficiency on A can be quite different, while the behaviour of the information rate normalised by A and D tends to resemble that of the Stokes efficiency. In comparison, the irreversibility measured by a normalised entropy production is independent of A. The results indicate the utility of the information geometry as a proxy of a motor efficiency.
Information Hiding Based on Two-Level Mechanism and Look-Up Table Approach
Authors: Pan Jeng-Shyang , Sun Xiao-Xue , Yang Hongmei , Snášel Václav , Chu Shu-Chuan
Published: February 2022

Information hiding can be seen everywhere in our daily life, and this technology improves the security of information. The requirements for information security are becoming higher and higher. The coverless information hiding with the help of mapping relationship has high capacity, but there is still a problem in which the secret message cannot find the mapping relationship and the process requires extra storage burden during the transmission. Therefore, on the basis of symmetric reversible watermarking, the paper introduces the two-level mechanism and novel arrangements to solve the problem of sufficient diversity of features and has better capacity and image quality as a whole. Besides, for the security of secret message, this paper designs a new encryption model based on Logistic mapping. This method only employs coverless information hiding of one carrier image to transmit secret message with the help of the two-level mechanism and look-up table. Reversible information hiding is applied to embed the generated location table on the original image so that ensures storage and security. The experiment certifies that the diversity of hash code is increased by using the two-level image mechanism and the quality of the image is excellent, which proves the advantages of the proposed symmetric method over the previous algorithm.
The Practitioner’s Eye: The Ricketts Technique Elements in Non-Extraction Treatment Camouflaging Skeletal Class III with Bite Asymmetry—A Case Series Presentation
Authors: Iwanicki Jaroslaw , Kawala Beata , Lis Joanna
Published: February 2022

The study presents four cases of camouflage treatment of skeletal Class III with occlusal asymmetry in adult patients. Cephalometric analysis was performed using two different reference lines, S-N and FH. The treatment was carried out without the use of additional fixed appliances, no extraoral elastics for maxillary protection, and no extraction of teeth in the mandible. In addition to the characteristic elements and archwires taken from the Ricketts technique, NiTi, TMA, Wilcock archwires, Class III asymmetric intraoral elastic and criss-cross as well as individualized biomechanical systems were used. It has been proven that mild and moderate skeletal Class III with occlusal asymmetry can be treated with orthodontic camouflage, without additional fixed appliances for expansion or protraction of the maxilla. Moreover, it has been shown that it is possible to effectively treat this defect without extracting the teeth in the mand.
On (n,1) Wave Attractors: Coordinates and Saturation Time
Authors: Sibgatullin Ilias , Petrov Alexandr , Xu Xiulin , Maas Leo
Published: February 2022

The simplest geometry of the domain, for which internal wave attractors were for the first time investigated both experimentally and numerically, has the shape of a trapezium with one vertical wall and one inclined lateral wall, characterized by two parameters. Using the symmetries of such a geometry we give an exact solution for the coordinates of the wave attractors with one reflection from each of the lateral boundaries and an integer amount n of reflections from each of the horizontal boundaries. The area of existence for each (n,1) attractor has the form of a triangle in the (d,τ) parameter plane, and the shape of this triangle is explicitly given with the help of inequalities or vertices. The expression for the Lyapunov exponents and their connection to the focusing parameters is given analytically. The corresponding direct numerical simulations with low viscosity fully support the analytical results and demonstrate that in bounded domains (n,1) wave attractors can be effective transformers of the global forcing into traveling waves. The saturation time from the state of rest to the final wave regime depends almost linearly on the number of cells, n.
Condition Monitoring of Rolling Bearing Based on Multi-Order FRFT and SSA-DBN
Authors: Ma Jie , Li Shule , Wang Xinyu
Published: February 2022

Owing to the symmetry of the rolling bearing structure and the rotating operation mode, the rolling bearing works in a complex environment. It is very easy to be submerged by noise and misdiagnosis. For the non-stationary signal in variable speed state, this paper presents a condition monitoring method based on deep belief network (DBN) optimized by multi-order fractional Fourier transform (FRFT) and sparrow search algorithm (SSA). Firstly, the fractional Fourier transform based on curve feature segmentation is used to filter the fault vibration signal and extract the fault feature frequency. Then, the fault features are input into the SSA-DBN model for training, and the bearing fault features are classified, identified, and diagnosed. Finally, the rotating machinery fault simulator in the laboratory of Ottawa University is taken as the practical application object to verify the effectiveness of the method. The experimental results show that the proposed method has higher recognition accuracy and stronger stability.
The Quasar CTD 135 Is Not a Compact Symmetric Object
Authors: Frey Sándor , Gabányi Krisztina É. , An Tao
Published: February 2022

The radio-loud quasar CTD 135 (2234+282, J2236+2828) has been proposed as a candidate compact symmetric object (CSO), based on its symmetric radio structure revealed by multi-frequency very long baseline interferometry (VLBI) imaging observations on milliarcsec angular scales. CSOs are known as young jetted active galactic nuclei (AGN) whose relativistic plasma jets are misaligned with respect to the line of sight. The peculiarity of CTD 135 as a CSO candidate was its detection in γ-rays, while the vast majority of known γ-ray emitting AGN are blazars with jets pointing close to our viewing direction. Since only a handful of CSOs are known as γ-ray sources, the unambiguous identification of a single candidate is important for studying this rare class of objects. By collecting and interpreting observational data from the recent literature, we revisit the classification of CTD 135. We present evidence that the object, based on its flat-spectrum radio core with high brightness temperature, variability at multiple wavebands, and infrared colours should be classified as a blazar rather than a CSO.
Absolute Configuration of Aliphatic Hydrocarbon Enantiomers Identified by Gas Chromatography: Theorized Application for Isoprenoid Alkanes and the Search of Molecular Biosignatures on Mars
Authors: Leseigneur Guillaume , Filippi Jean-Jacques , Baldovini Nicolas , Meierhenrich Uwe
Published: February 2022

Acyclic saturated hydrocarbon enantiomers were resolved by gas chromatography using a β-cyclodextrin-based chiral stationary phase. The stereospecific synthesis of single enantiomers of 4-methyloctane allowed to assign the absolute stereochemical configuration to the resolved enantiomers. Data show that the (S)-4-methyloctane shows higher chromatographic retention as compared to the (R)-4-methyloctane due to stronger van der Waals interactions with the β-cyclodextrin chiral selector. This introductive research presents future prospects for the separation of stereoisomers of larger branched hydrocarbons. We discuss the importance of chiral hydrocarbons, more precisely the stereochemistry of the isoprenoid alkanes pristane and phytane, as potential biosignatures stable on geological timescales. The origins of pristane and phytane in Earth sediments are presented, and we detail the implications for the search of extinct or extant life on Mars. The data presented here will help to systematically investigate the chirality of hydrocarbon enantiomers in biological and nonbiological samples and in samples to be analyzed by the ESA’s ExoMars rover to trace the chiral precursors of life in 2023.
A Collective Anomaly Detection Technique to Detect Crypto Wallet Frauds on Bitcoin Network
Authors: Shayegan Mohammad Javad , Sabor Hamid Reza , Uddin Mueen , Chen Chin-Ling
Published: February 2022

The popularity and remarkable attractiveness of cryptocurrencies, especially Bitcoin, absorb countless enthusiasts every day. Although Blockchain technology prevents fraudulent behavior, it cannot detect fraud on its own. There are always unimaginable ways to commit fraud, and the need to use anomaly detection methods to identify abnormal and fraudulent behaviors has become a necessity. The main purpose of this study is to use the Blockchain technology of symmetry and asymmetry in computer and engineering science to present a new method for detecting anomalies in Bitcoin with more appropriate efficiency. In this study, a collective anomaly approach was used. Instead of detecting the anomaly of individual addresses and wallets, the anomaly of users was examined. In addition to using the collective anomaly detection method, the trimmed_Kmeans algorithm was used for clustering. The results of this study show the anomalies are more visible among users who had multiple wallets. The proposed method revealed 14 users who had committed fraud, including 26 addresses in 9 cases, whereas previous works detected a maximum of 7 addresses in 5 cases of fraud. The suggested approach, in addition to reducing the processing overhead for extracting features, detect more abnormal users and anomaly behavior.
The Gaussian Mutational Barebone Dragonfly Algorithm: From Design to Analysis
Authors: Yuan Li , Kuang Fangjun , Zhang Siyang , Chen Huiling
Published: February 2022

The dragonfly algorithm is a swarm intelligence optimization algorithm based on simulating the swarming behavior of dragonfly individuals. An efficient algorithm must have a symmetry of information between the participating entities. An improved dragonfly algorithm is proposed in this paper to further improve the global searching ability and the convergence speed of DA. The improved DA is named GGBDA, which adds Gaussian mutation and Gaussian barebone on the basis of DA. Gaussian mutation can randomly update the individual positions to avoid the algorithm falling into a local optimal solution. Gaussian barebone can quicken the convergent speed and strengthen local exploitation capacities. Enhancing algorithm efficiency relative to the symmetric concept is a critical challenge in the field of engineering design. To verify the superiorities of GGBDA, this paper sets 30 benchmark functions, which are taken from CEC2014 and 4 engineering design problems to compare GGBDA with other algorithms. The experimental result show that the Gaussian mutation and Gaussian barebone can effectively improve the performance of DA. The proposed GGBDA, similar to the DA, presents improvements in global optimization competence, search accuracy, and convergence performance.
Methods of Retrieving Large-Variable Exponents
Authors: Yukalov Vyacheslav I. , Gluzman Simon
Published: February 2022

Methods of determining, from small-variable asymptotic expansions, the characteristic exponents for variables tending to infinity are analyzed. The following methods are considered: diff-log Padé summation, self-similar factor approximation, self-similar diff-log summation, self-similar Borel summation, and self-similar Borel–Leroy summation. Several typical problems are treated. The comparison of the results shows that all these methods provide close estimates for the large-variable exponents. The reliable estimates are obtained when different methods of summation are compatible with each other.
Symmetries of Thirring Models on 3D Lattices
Authors: Wipf Andreas W. , Lenz Julian J.
Published: February 2022

We review some recent developments about strongly interacting relativistic Fermi theories in three spacetime dimensions. These models realize the asymptotic safety scenario and are used to describe the low-energy properties of Dirac materials in condensed matter physics. We begin with a general discussion of the symmetries of multi-flavor Fermi systems in arbitrary dimensions. Then we review known results about the critical flavor number Ncrit of Thirring models in three dimensions. Only models with a flavor number below Ncrit show a phase transition from a symmetry-broken strong-coupling phase to a symmetric weak-coupling phase. Recent simulations with chiral fermions show that Ncrit is smaller than previously extracted with various non-perturbative methods. Our simulations with chiral SLAC fermions reveal that for four-component flavors Ncrit=0.80(4). This means that all reducible Thirring models with Nr=1,2,3,… show no phase transition with order parameter. Instead, we discover footprints of phase transitions without order parameter. These new transitions are probably smooth and could be used to relate the lattice Thirring models to Thirring models in the continuum. For a single irreducible flavor, we provide previously unpublished values for the critical couplings and critical exponents.
A Generalized Explicit Iterative Method for Solving Generalized Split Feasibility Problem and Fixed Point Problem in Real Banach Spaces
Authors: Ugwunnadi Godwin Chidi , Jolaoso Lateef Olakunle , Okeke Chibueze Christian
Published: February 2022

In this paper, we propose a generalized explicit algorithm for approximating the common solution of generalized split feasibility problem and the fixed point of demigeneralized mapping in uniformly smooth and 2-uniformly convex real Banach spaces. The generalized split feasibility problem is a general mathematical problem in the sense that it unifies several mathematical models arising in (symmetry and non-symmetry) optimization theory and also finds many applications in applied science. We designed the algorithm in such a way that the convergence analysis does not need a prior estimate of the operator norm. More so, we establish the strong convergence of our algorithm and present some computational examples to illustrate the performance of the proposed method. In addition, we give an application of our result for solving the image restoration problem and compare with other algorithms in the literature. This result improves and generalizes many important related results in the contemporary literature.
Performance Analysis of 2D and 3D Bufferless NoCs Using Markov Chain Models
Authors: Tatas Konstantinos
Published: February 2022

Performance analysis and design space exploration of bufferless Networks-on-Chip is done mainly through time-consuming cycle-accurate simulation, due to the chaotic nature of packet deflections, which have thus far prevented the development of an accurate analytical model. In order to raise the level of abstraction as well as capture the inherently probabilistic behavior of deflection routing, this paper presents a methodology for employing Markov chain models in the analysis of the behavior of bufferless Networks-on-Chip. A formal way of describing a bufferless NoC topology as a set of discrete-time Markov chains is presented. It is demonstrated that by combining this description with the network average distance, it is possible to obtain the expectation of the number of hops between any pair of nodes in the network as a function of the flit deflection probability. Comparisons between the proposed model and cycle-accurate simulation demonstrate the accuracy achieved by the model, with negligible computational cost. The useful range of the proposed model is quantified, demonstrating that it has an error of less than 10% for a significant proportion (between 33 and 75%) of the injection rate range below saturation. Finally, a simple equation for comparing mesh topologies with a “back-of-the-envelope” calculation is introduced.
The Role of Persistent Organic Pollutants in Obesity: A Review of Laboratory and Epidemiological Studies
Authors: Aaseth Jan , Javorac Dragana , Djordjevic Aleksandra , Bulat Zorica , Skalny Anatoly , Zaitseva Irina , Aschner Michael , Tinkov Alexey
Published: February 2022

Persistent organic pollutants (POPs) are considered as potential obesogens that may affect adipose tissue development and functioning, thus promoting obesity. However, various POPs may have different mechanisms of action. The objective of the present review is to discuss the key mechanisms linking exposure to POPs to adipose tissue dysfunction and obesity. Laboratory data clearly demonstrate that the mechanisms associated with the interference of exposure to POPs with obesity include: (a) dysregulation of adipogenesis regulators (PPARγ and C/EBPα); (b) affinity and binding to nuclear receptors; (c) epigenetic effects; and/or (d) proinflammatory activity. Although in vivo data are generally corroborative of the in vitro results, studies in living organisms have shown that the impact of POPs on adipogenesis is affected by biological factors such as sex, age, and period of exposure. Epidemiological data demonstrate a significant association between exposure to POPs and obesity and obesity-associated metabolic disturbances (e.g., type 2 diabetes mellitus and metabolic syndrome), although the existing data are considered insufficient. In conclusion, both laboratory and epidemiological data underline the significant role of POPs as environmental obesogens. However, further studies are required to better characterize both the mechanisms and the dose/concentration-response effects of exposure to POPs in the development of obesity and other metabolic diseases.
A Systematic Review of the Efficacy of Interventions to Control Aflatoxins in the Dairy Production Chain—Feed Production and Animal Feeding Interventions
Authors: Farkas Zsuzsa , Országh Erika , Engelhardt Tekla , Csorba Szilveszter , Kerekes Kata , Zentai Andrea , Süth Miklós , Nagy Attila , Miklós Gabriella , Molnár Krisztina , Rácz Csaba , Dövényi-Nagy Tamás , Ambrus Árpád , Győri Zoltán , Dobos Attila Csaba , Pusztahelyi Tünde , Pócsi István , Jóźwiak Ákos
Published: February 2022

The study presents a systematic review of published scientific articles investigating the effects of interventions aiming at aflatoxin reduction at the feed production and animal feeding phases of the milk value chain in order to identify the recent scientific trends and summarize the main findings available in the literature. The review strategy was designed based on the guidance of the systematic review and knowledge synthesis methodology that is applicable in the field of food safety. The Web of Science and EBSCOhost online databases were searched with predefined algorithms. After title and abstract relevance screening and relevance confirmation with full-text screening, 67 studies remained for data extraction, which were included in the review. The most important identified groups of interventions based on their mode of action and place in the technological process are as follows: low-moisture production using preservatives, acidity regulators, adsorbents and various microbiological additives. The results of the listed publications are summarized and compared for all the identified intervention groups. The paper aimed to help feed producers, farmers and relevant stakeholders to get an overview of the most suitable aflatoxin mitigation options, which is extremely important in the near future as climate change will likely be accompanied by elevated mycotoxin levels.