bluuebunny/crossref_metadata_2025 huggingface dataset:
Development and Validation of a Finite Element Model of Wear in UHMWPE Liner Using Experimental Data From Hip Simulator Studies
Authors: Kottan Nihal , Gowtham N. H. , Basu Bikramjit
Published: September 2021

The wear of acetabular liner is one of the key factors determining osseointegration and long-term performance of total hip joint replacement implants. The experimental measurements of wear in total hip replacement components are time and cost-intensive. While addressing this aspect, a finite element model of a hip joint bearing consisting of zirconia-toughened alumina femoral head and ultrahigh molecular weight polyethylene liner was developed to predict the dynamic wear response of the liner. The Archard–Lancaster equation, consisting of surface contact pressure, wear rate, and sliding distance, was employed to predict the wear of the acetabular liner. The contact pressure and wear at the articulating surface were found to decrease over time. A new computational method involving three-dimensional point clouds from the finite element analyzed results were used to construct wear maps. The model was able to predict the linear wear, over 2 × 106 cycles with relative errors ranging from 9% to 36% when compared to the published results. The increasing error percentage occurring primarily from the use of a constant wear rate was reduced to a maximum of 17% by introducing a correction factor. The volumetric rate was predicted with a maximum relative error of 7% with the implementation of the correction factor. When the model was implemented to study acetabular liners of diameters ranging from 28 to 36 mm, the linear wear was seen to decrease with an increase in femoral head diameter, which is in agreement with the clinical data. This study emphasizes the need to develop more such FEA-based computational studies to reliably predict and correlate with experimentally measured temporal evolution of wear of load-bearing articulating joints.
On the Self-Shielding in the Unresolved Resonance Range
Authors: Aldama Daniel Lopez , Trkov Andrej , Cullen Dermott E.
Published: September 2021

Resonance behavior is a feature of nuclear reaction cross sections. Resonance density increases with increasing incident particle energy and they begin to overlap, until they can no longer be resolved experimentally, but they still contribute to self-shielding and must be accounted for. This is usually done by representing them with statistical average parameters according to methods and approximations described in standard text-books. Self-shielding factors are commonly used in deterministic transport codes, while statistical Monte Carlo codes use probability tables or multiband parameters. An exercise was conducted at the International Atomic Energy Agency (IAEA) to validate codes and methods for generating data that account for self-shielding in deterministic and Monte Carlo codes. A simple numerical model problem was defined, considering a sphere of 1 m radius with a 20 MeV isotropic neutron source at the center. The chosen material for testing was 139La from the ENDF/B-VIII.0 library, which clearly showed anomalous behavior.
Describing the Mechanism of Instability Suppression Using a Central Pilot Flame With Coupled Experiments and Simulations
Authors: Li Jihang , Kwon Hyunguk , Seksinsky Drue , Doleiden Daniel , O'Connor Jacqueline , Xuan Yuan , Akiki Michel , Blust James
Published: September 2021

Pilot flames are commonly used to extend combustor operability limits and suppress combustion oscillations in low-emissions gas turbines. Combustion oscillations, a coupling between heat release rate oscillations and combustor acoustics, can arise at the operability limits of low-emissions combustors where the flame is more susceptible to perturbations. While the use of pilot flames is common in land-based gas turbine combustors, the mechanism by which they suppress instability is still unclear. In this study, we consider the impact of a central jet pilot on the stability of a swirl-stabilized flame in a variable-length, single-nozzle combustor. Previously, the pilot flame was found to suppress the instability for a range of equivalence ratios and combustor lengths. We hypothesize that combustion oscillation suppression by the pilot occurs because the pilot provides hot gases to the vortex breakdown region of the flow that recirculate and improve the static, and hence dynamic, stability of the main flame. This hypothesis is based on a series of experimental results that show that pilot efficacy is a strong function of pilot equivalence ratio but not pilot flow rate, which would indicate that the temperature of the pilot products as well as the combustion intensity of the pilot flame play more of a role in oscillation stabilization than the length of the pilot flame relative to the main flame. Further, the pilot-flame efficacy increases with pilot-flame equivalence ratio until it matches the main-flame equivalence ratio; at pilot equivalence ratios greater than the main equivalence ratio, the pilot-flame efficacy does not change significantly with pilot equivalence ratio. To understand these results, we use large-eddy simulation (LES) to provide a detailed analysis of the flow in the region of the pilot flame and the transport of radical species in the region between the main flame and pilot flame. The simulation, using a flamelet/progress variable-based chemistry tabulation approach and standard eddy viscosity/diffusivity turbulence closure models, provides detailed information that is inaccessible through experimental measurements.
Simulation and Experimental Study on Hydraulic Sandblasting Cutting in Uncontrolled Blowout Well
Authors: Tian Jialin , Wen Feng , Ge Tongxu , Hu Zhichao , Islam Shahriar
Published: September 2021

A nozzle structure of portable high-pressure hydraulic sandblasting cutting equipment is optimized through simulation analysis and experimental tests in this paper. The hydraulic sandblasting cutting technology uses high speed sand fluid jet for cutting operations, which improves the cutting efficiency. At the beginning, the model of computational fluid dynamics (CFD) was established to simulate different types, cylinder lengths, and cone angles of nozzle. Also, the comparison analyses of the jet characteristics of the nozzles are performed. The results show that the conical straight nozzle has better jet characteristics. Moreover, combined with mathematical methods, the experimental data of conical nozzle are processed and obtained further results, including the effects on cutting depth of working pressure, cutting transverse speed, and cutting target distance. The research models and results in this paper can provide reference for optimizing nozzle structure, improving nozzle cutting efficiency, and developing similar research.
Global Self-Optimizing Control With Data-Driven Optimal Selection of Controlled Variables With Application to Chiller Plant
Authors: Zhao Zhongfan , Li Yaoyu , Salsbury Timothy I. , House John M.
Published: September 2021

In this paper, we propose a global self-optimizing control (SOC) approach, where nonlinear dynamic model is obtained from historical data of plant operation via the framework of sparse identification of nonlinear dynamics (SINDy) combined with regularized regression. With the nonlinear static input–output map obtained by forcing steady-state operation, the globally optimal solutions of controlled variables (CVs) can be found by tracking the necessary conditions of optimality (NCO) in an analytical fashion. After validation with a numerical example, the proposed method is evaluated using a modelica-based dynamic model of a chilled-water plant. The economic objective for chiller plant operation is to minimize the total power of compressor, condenser water pump, and cooling tower fan, while the cooling tower fan speed and condenser water mass flow rate are used as manipulated inputs. The operating data are generated based on realistic ambient and load conditions and a best-practice rule-based strategy for chiller operation. The control structure with the SOC method yields a total power consumption close to the global optimum and substantially smaller than that of a best-practice rule-based chiller plant control strategy. The proposed method promises a global SOC solution using dynamic operation data, for cost-effective and adaptive control structure optimization.
Generalized Empirical Regret Bounds for Control of Renewable Energy Systems in Spatiotemporally Varying Environments
Authors: Haydon Ben , Cole Jack , Dunn Laurel , Keyantuo Patrick , Chow Fotini K. , Moura Scott , Vermillion Chris
Published: September 2021

This paper focuses on the empirical derivation of regret bounds for mobile systems that can optimize their locations in real-time within a spatiotemporally varying renewable energy resource. The case studies in this paper focus specifically on an airborne wind energy system, where the replacement of towers with tethers and a lifting body allows the system to adjust its altitude continuously, with the goal of operating at the altitude that maximizes net power production. While prior publications have proposed control strategies for this problem, often with favorable results based on simulations that use real wind data, they lack any theoretical or statistical performance guarantees. In this work, we make use of a very large synthetic dataset, identified through parameters from real wind data, to derive probabilistic bounds on the difference between optimal and actual performance, termed regret. The results are presented for a variety of control strategies, including maximum probability of improvement, upper confidence bound, greedy, and constant altitude approaches. In addition, we use dimensional analysis to generalize the aforementioned results to other spatiotemporally varying environments, making the results applicable to a wider variety of renewably powered mobile systems. Finally, to deal with more general environmental mean models, we introduce a novel approach to modify calculable regret bounds to accommodate any mean model through what we term an “effective spatial domain.”
Creep Deformation Property and Creep Life Evaluation of Super304H
Authors: Kimura Kazuhiro , Sawada Kota
Published: September 2021

Creep deformation behavior, creep strength property, and microstructural evolution during creep exposure were investigated on Super 304H steel for boiler tube. In the high stress and lower temperature regime, creep rupture strength of Super 304H steel is higher than that of SUS304H steel. The slope of stress versus time to rupture curve of Super 304H steel, however, becomes steeper with increase in creep exposure time and temperature, and the creep rupture strength of Super 304H steel becomes closer to that of SUS304H steel after the tens of thousands of hours at 700 °C and above. In the short-term, at 600 °C, creep rupture ductility increases with increase in creep rupture life. However, it tends to decrease after showing the maximum value and the creep rupture ductility decreases with increase in temperature. The complex shape of creep rate versus time curves, with two minima in creep rate, was observed at 600 °C. Several type precipitates of niobium carbonitride (Nb(C,N)), Z phase (NbCrN), and copper were observed in Super 304H steel, as well as M23C6 carbide and sigma phase observed in SUS304H steel. The change in slope of stress versus time to rupture curve is caused by disappearance of precipitation strengthening effect during creep exposure. Accuracy of creep rupture life evaluation was improved by stress range splitting method which takes into accounts of the change in slope of stress versus time to rupture curves was demonstrated.
Reduced Order Design Optimization of Liquid Cooled Heat Sinks
Authors: Lad Aniket Ajay , James Kai A. , King William P. , Miljkovic Nenad
Published: September 2021

The recent growth in electronics power density has created a significant need for effective thermal management solutions. Liquid-cooled heat sinks or cold plates are typically used to achieve high volumetric power density cooling. A natural tradeoff exists between the thermal and hydraulic performance of a cold plate, creating an opportunity for design optimization. Current design optimization methods rely on computationally expensive and time consuming computational fluid dynamics (CFD) simulations. Here, we develop a rapid design optimization tool for liquid cooled heat sinks based on reduced-order models for the thermal-hydraulic behavior. Flow layout is expressed as a combination of simple building blocks on a divided coarse grid. The flow layout and geometrical parameters are incorporated to optimize designs that can effectively address heterogeneous cooling requirements within electronics packages. We demonstrate that the use of population-based searches for optimal layout selection, while not ensuring a global optimum solution, can provide optimal or near-optimal results for most of the test cases studied. The approach is shown to generate optimal designs within a timescale of 60–120 s. A case study based on cooling of a commercial silicon carbide (SiC) electronics power module is used to demonstrate the application of the developed tool and is shown to improve the performance as compared to an aggressive state-of-the-art single-phase liquid cooling solution by reducing the SiC junction-to-coolant thermal resistance by 25% for the same pressure drop.
An ecohydrological journey of 4500 years reveals a stable but threatened precipitation–groundwater recharge relation around Jerusalem
Authors: Fatichi Simone , Peleg Nadav , Mastrotheodoros Theodoros , Pappas Christoforos , Manoli Gabriele
Published: September 2021

Climate change can alter Jerusalem’s precipitation–groundwater recharge relation, which has been stable for 4500 years.
Zona incerta subpopulations differentially encode and modulate anxiety
Authors: Li Zhuoliang , Rizzi Giorgio , Tan Kelly R.
Published: September 2021

The zona incerta is an anxiety sensor and modulator.
Topological magnon insulators in two-dimensional van der Waals ferromagnets CrSiTe
3
and CrGeTe
3
: Toward intrinsic gap-tunability
Authors: Zhu Fengfeng , Zhang Lichuan , Wang Xiao , dos Santos Flaviano José , Song Junda , Mueller Thomas , Schmalzl Karin , Schmidt Wolfgang F. , Ivanov Alexandre , Park Jitae T. , Xu Jianhui , Ma Jie , Lounis Samir , Blügel Stefan , Mokrousov Yuriy , Su Yixi , Brückel Thomas
Published: September 2021

A new family of topological magnon insulators with intrinsic gap-tunability is realized in 2D van der Waals ferromagnets.
Neutrophil extracellular traps enhance macrophage killing of bacterial pathogens
Authors: Monteith Andrew J. , Miller Jeanette M. , Maxwell C. Noel , Chazin Walter J. , Skaar Eric P.
Published: September 2021

S100A9 regulates mitochondrial-mediated neutrophil extracellular trap formation, which augments macrophage bactericidal activity.
Vaccine-driven lung TRM cells provide immunity against
Klebsiella
via fibroblast IL-17R signaling
Authors: Iwanaga Naoki , Chen Kong , Yang Haoran , Lu Shiping , Hoffmann Joseph P. , Wanek Alanna , McCombs Janet E. , Song Kejing , Rangel-Moreno Javier , Norton Elizabeth B. , Kolls Jay K.
Published: September 2021

A subunit mucosal vaccine conferred protection against heterologous
Klebsiella pneumoniae
strains, via IL-17R signaling in lung fibroblasts.
To the Issue of the Memristor’s HRS and LRS States Degradation and Data Retention Time
Authors: Fadeev A. V. , Rudenko K. V.
Published: September 2021

In this review of experimental studies, the retention time and endurance of memristor RRAM memory elements based on reversible resistive switching in oxide dielectrics are studied. The influence of external parameters—switching pulses and ambient temperature—as well as internal factors—evolution of the concentration of oxygen vacancies in the filament region, the material, structure; the thickness of the active dielectric layer, material of metal electrodes on the long-term stability of high resistance state (HRS) and the low resistance state (LRS) of the memristor is discussed.
Estimating catch curve mortality based on relative return rates of coded wire tagged lake trout in US waters of Lake Huron
Authors: He Ji X. , Ebener Mark P. , Clark Richard D. , Bence James R. , Madenjian Charles P. , McDonnell Kevin N. , Kornis Matthew S. , Bronte Charles R.
Published: September 2021

We estimated total mortality using catch curves based on relative return rates (RRs) of coded wire tagged lake trout (Salvelinus namaycush) in US waters of Lake Huron. RR was calculated as age-specific CPUE per million of fish stocked. Annual mortality for the late 1990s through early 2000s was estimated as 38% from the 1991–1995 year classes, with an effective age range of 5–10 years, and then was estimated as 24% for the post-2000 period from the 1996–2009 year classes. The two estimates from simple catch curve regressions based on average RR at age values were the same as from a mixed model with individual RR values from all stocking events. These two estimates were also comparable to the findings from statistical catch-at-age assessments with fundamentally different assumptions. Our approach is not constrained by the assumption that the expected recruitment is a constant over time and thus has the advantage to use multiple observations on each age from multiple cohorts. Our approach has broad applicability to aquatic ecosystems in which multiple mark-and-release events of fish stocking have been implemented.
Tied links in various topological settings
Authors: Diamantis Ioannis
Published: September 2021

Tied links in [Formula: see text] were introduced by Aicardi and Juyumaya as standard links in [Formula: see text] equipped with some non-embedded arcs, called ties, joining some components of the link. Tied links in the Solid Torus were then naturally generalized by Flores. In this paper, we study this new class of links in other topological settings. More precisely, we study tied links in the lens spaces [Formula: see text], in handlebodies of genus [Formula: see text], and in the complement of the [Formula: see text]-component unlink. We introduce the tied braid monoids [Formula: see text] by combining the algebraic mixed braid groups defined by Lambropoulou and the tied braid monoid, and we formulate and prove analogues of the Alexander and the Markov theorems for tied links in the 3-manifolds mentioned above. We also present an [Formula: see text]-move braid equivalence for tied braids and we discuss further research related to tied links in knot complements and c.c.o. 3-manifolds. The theory of tied links has potential use in some aspects of molecular biology.
Axial shape and pairing evolution of 82−106Zr, 86−112Mo, 90−116Ru and 94−122Pd isotopic chains in the framework of the deformed BCS approach
Authors: Saleh Yousef M. , Elsharkawy H. M.
Published: September 2021

The Deformed Bardeen–Cooper–Schrieffer (DBCS) approach is used to study the axial shape evolution of even–even [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] isotopic chains. Regarding the residual interaction, both like-particle pairing and unlike-particle pairing are considered in this study. It is found that, in general, the proton–neutron pairing does not affect the ground state shapes of nuclei except for few nuclei, where the inclusion of proton–neutron pairing predicts spherical shape in the ground state rather than a deformed one in case of considering only like-particle pairing. Pairing gaps, energies and strengths of both like- and unlike-pairing modes are discussed. One can conclude that the contribution of proton–neutron pairing to the total pairing energy is not negligible, even if the neutron excess number is high.
Multipliers and unicentral Leibniz algebras
Authors: Mainellis Erik
Published: September 2021

In this paper, we prove Leibniz analogues of results found in Peggy Batten’s 1993 dissertation. We first construct a Hochschild–Serre-type spectral sequence of low dimension, which is used to characterize the multiplier in terms of the second cohomology group with coefficients in the field. The sequence is then extended by a term and a Ganea sequence is constructed for Leibniz algebras. The maps involved with these exact sequences, as well as a characterization of the multiplier, are used to establish criteria for when a central ideal is contained in a certain set seen in the definition of unicentral Leibniz algebras. These criteria are then specialized, and we obtain conditions for when the center of the cover maps onto the center of the algebra.
GLOBAL CITIES IN INTERNATIONAL NETWORKS OF INNOVATORS
Authors: EDET S. , PANZARASA P. , RICCABONI M.
Published: September 2021

Recent studies on international networks have investigated the role of global cities as catalysts of knowledge flows. In this paper, we examine global cities in transnational networks of innovators. To assess the likelihood of scientists and inventors from different cities to take part in international teams, we propose a measure based on 3-hyperedges in the collaboration network constructed from scientific publications and patents. This measure is used to identify the most competitive global cities in the international network of innovators. To this end, we construct a null model based on the hypergeometric ensembles of random graphs. We find that five US cities play a leading role in transnational networks of innovators. Among them, San Francisco stands out as the most globalized city.
Convolution Quadrature Time-Domain Boundary Element Method for Viscoelastic Wave Scattering by Many Cavities in a 3D Infinite Space
Authors: Saitoh Takahiro , Takeda Haruhiko
Published: September 2021

This paper presents a time-domain boundary element method (BEM) for viscoelastic wave scattering by many cavities in 3D infinite space. The convolution quadrature method (CQM) is applied to the convolutions of the time-domain boundary integral equation in order to improve the numerical stability of BEM. Scattering of an incident wave by cavities in a viscoelastic solid is solved by the developed time-domain BEM. The incident wave propagating in a viscoelastic solid in time-domain is obtained using the inverse Fourier transform of that in frequency-domain. In addition, the hybrid parallelization using OpenMP and MPI is used to save the computational time and memory.
ADJUNCTIVE THERAPY FOR FETLOCK FLEXURAL DEFORMITIES ACCOMPANIED BY A DEEP TISSUE INJURY IN A CALF: A CASE REPORT
Authors: Thongrueang Natcha , Lee Hsu-Hsun
Published: September 2021

A five-day-old Holstein Friesian male calf was presented for the evaluation of severe fetlock flexural deformities with a large pressure ulcer over the right metacarpal bone. Superficial and deep digital flexor tenotomy was performed. The surgical wound recovered well, but 15 days after surgery, the skin over the pressure ulcer was starting to fall away and exposing tendon and muscle. A hoof toe-extension shoe was applied to decrease pressure on the wound. The wound had a moderate bacterial infection and slowly responded to cleansing twice a day with 0.9% normal saline, 10% povidone iodine and a topical antibiotic. Topical autologous platelet-rich plasma (PRP) was then applied to the lesion ([Formula: see text][Formula: see text]cm) twice. The wound showed rapid tissue regeneration, good quality wound healing and no complications. After PRP treatment, the lesion size decreased ([Formula: see text][Formula: see text]cm). At this point, 0.9% normal saline cleansing and a bandage were applied until the wound had completely healed. This case report suggests that the hoof toe-extension shoe and topical dressing with autologous PRP, as a combination treatment, could be effective for fetlock flexural deformities with skin defects or delayed wound healing in large animals.
Fabrication of Mesoporous Graphene@Ag@TiO2 Composite Nanofibers Via Electrospinning as Anode Materials for High-Performance Li-Ion Batteries
Authors: Xia M. M. , Li J. , Zhang Y. Y. , Kang D. N. , Zhang Y. L.
Published: September 2021

Nanosized TiO2 has been actively developed as a low-cost and environment-friendly anode material for lithium-ion batteries (LIBs), but its poor electronic conductivity seriously restricts its practical applications. This drawback is addressed in this work by the fabrication of one-dimensional mesoporous graphene@Ag@TiO2 composite nanofibers as anode materials for high-performance LIBs. The materials were prepared via electrospinning combined with annealing treatment, and the effects of graphene addition on the microstructure and electrochemical performance of the resulting mesoporous graphene@Ag@TiO2 nanofibers were investigated in detail. Ag@TiO2 nanofibers with the optimal amount of graphene displayed a maximum initial discharge capacity of [Formula: see text] at [Formula: see text] and retained a discharge capacity of [Formula: see text] at [Formula: see text] after 100 cycles. These results reflect the excellent cycling stability of the material. The average specific discharge capacity of the nanofibers ([Formula: see text] at [Formula: see text] was two-fold higher than that of samples without graphene, and their discharge capacity returned to [Formula: see text] (approximately [Formula: see text] for other nanofibers) when the current density was recovered to the initial value ([Formula: see text]. Electrochemical impedance spectroscopic measurements confirmed that the conductivity of the electrode was [Formula: see text], which is higher than that of bare mesoporous Ag@TiO2 ([Formula: see text]). Thus, one-dimensional mesoporous graphene@Ag@TiO2 nanofibers can be regarded as a promising anode material for LIBs.
THE DIGITAL ECOSYSTEM AROUND THE WORLD: A COMPOSITE INDICATOR ANALYSIS
Authors: ÁCS ZOLTÁN J. , LAFUENTE ESTEBAN , SZERB LÁSZLÓ
Published: September 2021

This study employs the “Benefit of the Doubt” method rooted in non-parametric techniques to evaluate the digital ecosystem of 116 countries for the year 2019. By scrutinizing the relative efficiency of countries’ digital ecosystem based on the Digital Platform Economy index (DPE index), the proposed analysis of composite indicators allows the computation of endogenous (country-specific) weights that can be used for developing a more informed policy. The results show that countries prioritize different aspects of their digital ecosystem. Additionally, the findings reveal significant differences in the configuration of the digital ecosystem around the world. These results confirm that, contrary to homogeneous prescription, tailor-made policy is necessary if the objective is to optimize the resources deployed to enhance the digital ecosystem.
Altered stress hormone levels affect in vivo vascular function in the hAPP23+/− overexpressing mouse model of Alzheimer’s disease
Authors: Hendrickx Jhana O. , De Moudt Sofie , Van Dam Debby , De Deyn Peter Paul , Fransen Paul , De Meyer Guido R. Y.
Published: September 2021

We showed that male amyloid precursor protein (APP) transgenic mice have higher circulating stress hormone levels. As a result, higher systolic blood pressure and pulse-wave velocity were measured in vivo in addition to a smaller α-adrenergic receptor-dependent contraction upon ex vivo stimulation with phenylephrine. Our findings highlight the need for more frequent assessment of circulating stress hormone levels and PWV measurements in daily clinical practice for people at risk of Alzheimer’s disease.
Intelligent Detection System Enabled Attack Probability Using Markov Chain in Aerial Networks
Authors: Khan Inam Ullah , Abdollahi Asrin , Alturki Ryan , Alshehri Mohammad Dahman , Ikram Mohammed Abdulaziz , Alyamani Hasan J. , Khan Shahzad
Published: September 2021

The Internet of Things (IoT) plays an important role to connect people, data, processes, and things. From linked supply chains to big data produced by a large number of IoT devices to industrial control systems where cybersecurity has become a critical problem in IoT‐powered systems. Denial of Service (DoS), distributed denial of service (DDoS), and ping of death attacks are significant threats to flying networks. This paper presents an intrusion detection system (IDS) based on attack probability using the Markov chain to detect flooding attacks. While the paper includes buffer queue length by using queuing theory concept to evaluate the network safety. Also, the network scenario will change due to the dynamic nature of flying vehicles. Simulation describes the queue length when the ground station is under attack. The proposed IDS utilizes the optimal threshold to make a tradeoff between false positive and false negative states with Markov binomial and Markov chain distribution stochastic models. However, at each time slot, the results demonstrate maintaining queue length in normal mode with less packet loss and high attack detection.
Research on an Obstacle Avoidance Method for UAV
Authors: He Zhenqi , Yao Lu
Published: September 2021

With the continuous development of UAV technology, UAV has been widely used in various industries. In the flight process of UAV, UAV often changes the given path because of obstacles (including static nonliving body and moving living body). According to the properties of obstacles and the characteristics of UAV, standard Kalman filter is used for nonmaneuvering targets, and sigma point Kalman filter is used for maneuvering targets. In the aspect of obstacle avoidance, the minimum search method is used to get the initial population of local programming. Then, the improved genetic algorithm is run. Combined with the predicted obstacle features, the local planning path can be obtained. Finally, the local planning path and global planning path are combined to generate the planning path with new obstacles. At the end of the paper, the obstacle avoidance strategies of static and moving obstacles are simulated. The simulation results show that this method has fast convergence speed and good feasibility and can flexibly deal with the obstacle avoidance and local path planning of various new obstacles.
Broadband Dual-Polarized Multidipole Antenna for Base Station Applications
Authors: Huang Yuxuan , Zhu Zeqi , Cai Shuting , Xiong Xiaoming , Liu Yuan
Published: September 2021

A wideband dual-polarized multidipole antenna for base station applications is proposed. It consists of a pair of large square-shaped loop dipoles and a pair of small rectangle loop dipoles as radiation elements. A pair of small rectangle loop dipoles is fed by T-shaped feed structure which is in the large square-shaped loop dipoles radiating arm so that the antenna generates an additional resonance and obtains a wider bandwidth. The proposed antenna was fabricated and measured, and the results show that the antenna achieves a wide impedance bandwidth of 63.7 % with VSWR<1.5 covering the frequency range from 1.55 to 3 GHz. A high isolation is better than 29 dB within the operating frequency bandwidth. Moreover, an average gain 8 dBi and a stable radiation pattern with 3 dB beamwidth of 69° ± 4° at H-plane are obtained.
Analytic Normalized Solutions of 2D Fractional Saint-Venant Equations of a Complex Variable
Authors: Alarifi Najla M. , Ibrahim Rabha W.
Published: September 2021

Saint-Venant equations describe the flow below a pressure surface in a fluid. We aim to generalize this class of equations using fractional calculus of a complex variable. We deal with a fractional integral operator type Prabhakar operator in the open unit disk. We formulate the extended operator in a linear convolution operator with a normalized function to study some important geometric behaviors. A class of integral inequalities is investigated involving special functions. The upper bound of the suggested operator is computed by using the Fox-Wright function, for a class of convex functions and univalent functions. Moreover, as an application, we determine the upper bound of the generalized fractional 2-dimensional Saint-Venant equations (2D-SVE) of diffusive wave including the difference of bed slope.
Diagnostic Value of Chest CT Images Based on Full Model Iterative Reconstruction Algorithm for Lung Cancer Patients
Authors: Li Xia , Song Zhanqiang , Shen Guiping , Huang Ying , Chen Junyu
Published: September 2021

Objective. To evaluate the value of low-dose CT scanning and full model iteration recombinant technology peripheral lung cancer in the paper using whole model iterative reconstruction algorithm and compare iterative model-wide restructuring, reorganization part of an iterative algorithm, affecting filtered back projection image quality. Method. Fifty-two patients with peripheral lung cancer, all of whom were diagnosed by pathological biopsy, were selected for the study. All patients received three scans of low-dose chest CT, next-low-dose, and low-dose, after which the raw data of three different doses were reconstructed using filtered back-projection, iterative partial algorithm reconstitution, and reconstructed full-model iteration, respectively, and the effect of each algorithm on the processing of chest CT images of peripheral lung cancer at different doses and the diagnosis of the disease were compared after the reconstitution was completed. Results. The average effective radiation dose for the low-dose group was (0.3±0.02) mSv At each dose level, image noise objective recombinant whole iterative model < part of the reorganization of the iterative algorithm < filtered back projection, the difference was significant. In the case of lung lesions, the full-model iterative algorithm has similar evaluation power to the LD-partial iterative algorithm. When a patient’s body mass index (BMI) > 25 kg/m2, the whole model iteration reorganization image quality is reduced, but the lesions-to-noise ratio (SNR) is unaffected. Conclusion. The combination of a very low dose of recombinant iterative model as compared to full-dose low-dose chest CT dose can be reduced to 88% but does not reduce the overall image quality and can show good radiological signs of peripheral lung cancer and not affect BMI patients.
Exact Augmented Perpetual Manifolds: Corollary about Different Mechanical Systems with Exactly the Same Motions
Authors: Georgiades Fotios
Published: September 2021

Perpetual points have been defined in mathematics recently, and they arise by setting accelerations and jerks equal to zero for nonzero velocities. The significance of perpetual points for the dynamics of mechanical systems is ongoing research. In the linear natural, unforced mechanical systems, the perpetual points form the perpetual manifolds and are associated with rigid body motions. Extending the definition of perpetual manifolds, by considering equal accelerations, in a forced mechanical system, but not necessarily zero, the solutions define the augmented perpetual manifolds. If the displacements are equal and the velocities are equal, the state space defines the exact augmented perpetual manifolds obtained under the conditions of a theorem, and a characteristic differential equation defines the solution. As a continuation of the theorem herein, a corollary proved that different mechanical systems, in the exact augmented perpetual manifolds, have the same general solution, and, in case of the same initial conditions, they have the same motion. The characteristic differential equation leads to a solution defining the augmented perpetual submanifolds and the solution of several types of characteristic differential equations derived. The theory in a few mechanical systems with numerical simulations is verified, and they are in perfect agreement. The theory developed herein is supplementing the already-developed theory of augmented perpetual manifolds, which is of high significance in mathematics, mechanics, and mechanical engineering. In mathematics, the framework for specific solutions of many degrees of freedom nonautonomous systems is defined. In mechanics/physics, the wave-particle motions are of significance. In mechanical engineering, some mechanical system’s rigid body motions without any oscillations are the ultimate ones.
Study on Grouted Body Deterioration Mechanism of Sand Layer in Seawater Environment
Authors: Wang Hongbo , Li Zhipeng , Wang Xiaoguo , Zhang Qingsong , Zhang Lianzhen
Published: September 2021

Water‐rich sand is a common stratum in marine underground engineering. Grouting is the most common method for solving geological disasters in water‐rich sand. However, the marine environment differs greatly from the land environment. The erosion and seepage of seawater ion cause significant deterioration of grouted body, which reduces the physical and mechanical properties of grouted body. The maintenance of grouted body performance is the guarantee of long‐term safe operation of the tunnel in the marine environment. In order to solve the problem of long‐life grouting design for sand layer in seawater environment, an accelerated test of grouted body erosion under seawater erosion environment is designed to study the mesomorphological characteristics of seawater erosion on grouted body erosion and to reveal the mechanism of seawater erosion and solids. The evolution law of grouting plus solid strength under different slurry water‐cement ratios and different seawater erosion time conditions is analyzed. The results show that the grouting plus solid effective time for water‐cement ratios of 0.8 : 1, 1 : 1, 1.4 : 1, and 2 : 1 is 75a, 60a, 30a, and 15a; the index of strength degradation ratio of seawater environment to grouting plus solids is proposed, and the quantitative relationship between seawater erosion time and grouting plus solids strength is established, which provides theoretical basis for sand layer grouting reinforcement in seawater environment. We hope to provide some reference for the design and construction of sand grouting in seawater environment.
Crocetin Exerts Its Anti‐inflammatory Property in LPS‐Induced RAW264.7 Cells Potentially via Modulation on the Crosstalk between MEK1/JNK/NF‐κB/iNOS Pathway and Nrf2/HO‐1 Pathway
Authors: Wen Yi-Ling , He Ziyu , Hou De-Xing , Qin Si
Published: September 2021

Crocetin is a main bioactive component with a carotenoid skeleton in Gardenia jasminoides, a typical traditional Chinese medicine with a long history in Southeast Asia. Crocetin is being commonly consumed as spices, dyes, and food colorants. Recent pharmacological studies had implied that crocetin may possess potent anti‐inflammatory properties; however, the underlying molecular mechanism is not fully elucidated. In the present study, the regulatory effect of crocetin on redox balance was systematically investigated in lipopolysaccharide‐ (LPS‐) stimulated RAW264.7 cells. The results showed that crocetin dose‐dependently inhibited LPS‐induced nitric oxide production and inducible nitric oxide synthase (iNOS) expression in RAW264.7 cells. Molecular data revealed that crocetin exerted its anti‐inflammatory property by inhibiting the MEK1/JNK/NF‐κB/iNOS pathway and activating the Nrf2/HO‐1 pathway. The shRNA‐knockdown (KD) of MEK1 and ERK1 confirmed that the activation of MEK1 and inhibition of JNK mediated the anti‐inflammatory effect of crocetin. Moreover, the pull‐down assay and computational molecule docking showed that crocetin could directly bind to MEK1 and JNK1/2. It is noticed that both KD and knockout (KO) of HO-1 gene blocked this action. More detailed data have shown that HO-1‐KO blocked the inhibition of p‐IκB‐α by crocetin. These data indicated that crocetin exerted its anti‐inflammatory property via modulating the crosstalk between the MEK1/JNK/NF‐κB/iNOS pathway and the Nrf2/HO‐1 pathway, highlighting HO‐1 as a major player. Therefore, the present study reveals that crocetin can act as a potential candidate for redox‐balancing modulation in charge of its anti‐inflammatory and chemopreventive effect, which strengthens its potency in the subsequent clinic application in the near future.
Exemplifying the Effects Using WetSpass Model Depicting the Landscape Modifications on Long‐Term Surface and Subsurface Hydrological Water Balance in Bilate Basin, Ethiopia
Authors: Nannawo Abera Shigute , Lohani Tarun Kumar , Eshete Abunu Atlabachew
Published: September 2021

The alteration of spatial patterns of landscape interrupts water balance components in Bilate basin of Ethiopia. The aim is to characterize the spatio‐temporal variation of surface‐subsurface hydrological water balance using the WetSpass model comprising of soil type, topography, groundwater depth, and slope. Environment for Visualizing Images (ENVI) and Arc‐GIS software were assimilated for the classification of Landsat images from 1989 to 2019 replicating the forest, shrub, and grasslands which decrease by 4.0%, 9.41%, and 14.87%, respectively, and agricultural land increasing by 27.06% from 1989 to 2019. The goodness of fit in surface runoff and subsurface flow for the two model outputs with the square of regression (R2) of 0.79 and 0.81, while the root mean square errors (RMSEs) 8.26 mm and 8.39 mm for 1989 and 2019, respectively, were calculated. Average annual interception, groundwater recharge, surface runoff, and actual‐evapotranspiration were 36.4 mm, 127.34 mm, 614.95 mm, and 517.59 mm, respectively, revealing that WetSpass works remarkably in simulating the components of the hydrological water balance.
Estrogen Replacement Therapy Induces Antioxidant and Longevity‐Related Genes in Women after Medically Induced Menopause
Authors: Borrás C. , Ferrando M. , Inglés M. , Gambini J. , Lopez-Grueso R. , Edo R. , Mas-Bargues C. , Pellicer A. , Viña J.
Published: September 2021

Females live longer than males in many species, including humans, and estrogens are in part responsible for this protection against aging. We reported previously that estrogens can protect rats against oxidative stress, by inducing antioxidant and longevity‐related genes. Thus, this study was aimed at confirming the ability of estrogens to upregulate antioxidant and longevity‐related genes in humans. For this purpose, we selected 16 women of reproductive age (18‐42 years old) undergoing a fertility treatment that includes a medically induced menopause, at the Valencian Infertility Institute. We took blood samples at each time point of the treatment (basal, induced menopause, estrogen, and estrogen plus progesterone replacement therapy). mRNA expression of antioxidant and longevity‐related genes in peripheral blood mononuclear cells (PBMC) was determined by real‐time reverse transcriptase‐polymerase chain reaction (RT‐PCR). Determination of reduced glutathione (GSH) in total blood was carried out using high‐performance liquid chromatography (HPLC). As expected, we found that medically induced menopause significantly decreased sexual hormone (estrogens and progesterone) levels. It also lowered glutathione peroxidase (GPx), 16S rRNA, P21, and TERF2 mRNA expression and blood GSH levels. Estrogen replacement therapy significantly restored estrogen levels and induced mRNA expression of manganese superoxide dismutase (MnSOD), GPx, 16S rRNA, P53, P21, and TERF2 and restored blood GSH levels. Progesterone replacement therapy induced a significant increase in MnSOD, P53, sestrin 2 (SENS2), and TERF2 mRNA expression when compared to basal conditions. These findings provide evidence for estrogen beneficial effects in upregulating antioxidant and longevity‐related genes in women.
Factors Affecting the Organizational Adoption of Secure Community Cloud in KSA
Authors: Aldahwan Nouf S. , Ramzan Muhammed S.
Published: September 2021

Cloud computing is an innovative technology and gaining popularity in variety of organization to meet their computing requirements. Saudi Arabia is considered as the Gulf region’s high economy and the future market for cloud computing technologies. Analysis of its economic benefits, adequacy from technical, organizational, and environmental viewpoints, and possible challenges should precede the implementation of new technologies. Latest research and developments on cloud computing are causally linked to the emphasis on applications, advantages, expenditures, and technology. The community cloud (CC) is an impressive replacement for different organizations as it promotes cost reduction and quality enhancement. However, this research was performed to study the perception of IT and telecommunications company employees and computer users who support community cloud. The current state of community cloud adoption in KSA is analyzed. Present challenges impact the adoption of community cloud in Saudi Arabia and define the motivation factors. Questionnaires were used to accomplish these goals. Questionnaires were designed to accomplish these goals and it is implemented using survey. Questions about confidence are also a key issue. Issues such as data privacy, integrity, and availability are the factors influencing the organization’s acceptance of community cloud.
Comparison of Intravitreal Dexamethasone Implant and Ranibizumab in Vitrectomized Eyes with Diabetic Macular Edema
Authors: Wang Jia-Kang , Huang Tzu-Lun , Chang Pei-Yao , Ho Wei-Ting , Hsu Yung-Ray , Chen Fang-Ting , Chen Yun-Ju
Published: September 2021

Purpose. This retrospective study aimed to compare the efficacy of intravitreal ranibizumab (IVR) and intravitreal dexamethasone implant (IDI) for pseudophakic vitrectomized eyes with diabetic macular edema (DME) in a single institution. Methods. Pseudophakic vitrectomized eyes with treatment-naïve center-involved DME were enrolled, with one eye in each patient. They were divided into two groups: one group receiving IDI every 3 to 4 months and another group receiving IVR using 3 monthly plus treat-and-extend injections, all with monthly follow-up for 6 months. Switch of intravitreal drugs or deferred macular laser was not allowed. Primary outcome measures included change in central foveal thickness (CFT) in 1 mm by spectral-domain optical coherence tomography and best-corrected visual acuity (BCVA) at Month 6. Results. Twenty-two eyes were included in the IDI group and 26 eyes in the IVR group. The baseline demographics, glycosylated hemoglobin level, intraocular pressure (IOP), BCVA, and CFT did not significantly differ (

p
>
0.05

). Compared to baseline data, CFT decreased and BCVA improved significantly after either IDI or IVR at Month 6 (

p
<
0.05

). Significantly better mean final BCVA (0.38 logMAR vs. 0.62 logMAR,

p
=
0.04

), more mean visual gain (−0.30 logMAR vs. −0.15 logMAR,

p
=
0.02

), lower mean final CFT (310.9 μm vs. 384.2 μm,

p
=
0.04

), and larger mean CFT decrease (−150.0 μm vs. −60.1 μm,

p
=
0.03

) were found in the IDI group compared to those in the IVR group. A smaller mean treatment number (2.6 vs. 5.6,

p
<
0.001

) and higher rate of postinjection ocular hypertension requiring topical hypotensive agent therapy (27.3% vs. 0%,

p
=
0.0002

) were demonstrated in the IDI group than those in the IVR group. Conclusion. We concluded that IDI and IVR can both effectively treat vitrectomized eyes with DME. Dexamethasone implants had significantly better visual/anatomical improvement, smaller treatment number, and higher rate of elevated IOP after injection than IVR in pseudophakic vitrectomized eyes with DME in a 6-month period.
Measuring Synchronization between Spikes and Local Field Potential Based on the Kullback–Leibler Divergence
Authors: Yin Liyong , Zhang Guangrong , Yin Fuzai
Published: September 2021

Neurophysiological studies have shown that there is a close relationship between spikes and local field potential (LFP), which reflects crucial neural coding information. In this paper, we used a new method to evaluate the synchronization between spikes and LFP. All possible phases of LFP from −π to π were first binned into a freely chosen number of bins; then, the probability of spikes falling in each bin was calculated, and the deviation degree from the uniform distribution based on the Kullback–Leibler divergence was calculated to define the synchronization between spikes and LFP. The simulation results demonstrate that the method is rapid, basically unaffected by the total number of spikes, and can adequately resist the noise of spike trains. We applied this method to the experimental data of patients with intractable epilepsy, and we observed the synchronization between spikes and LFP in the formation of memory. These results show that our proposed method is a powerful tool that can quantitatively measure the synchronization between spikes and LFP.