bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Pore Additives on Deep Eutectic Solvent Immobilization for CO₂/N₂ Gas Separation Using Supported Deep Eutectic Solvent Membranes
Authors: Mohd Nasib Amira , Jullok Nora , Mohamad Dzahir Mohd Irfan Hatim , Luis Patricia , Der Bruggen Bart Van
Published: July 2021

This work analyses the effect of two different pore additives focusing on polyethylene glycol (PEG) and lithium chloride (LiCl) at different concentrations on the immobilization of a deep eutectic solvent (DES) in a polyvinylidene fluoride-co-polytetrafluoroethylene (PVDF-co-PTFE) membrane. Two compounds were chosen to synthesized the DES; choline chloride as halide salt and ethylene glycol as a hydrogen bond donor.  The DES was impregnated onto the membrane pores by applying a vacuum-based technique. The membranes were prepared via phase inversion by means of immersion precipitation. For characterization purposes, scanning electron microscopy (SEM-EDX) was used to analyse the morphology of the supported- DES-membranes together with energy dispersive X-ray spectrometry. The gravimetric method was applied to calculate the porosity, while the membrane performance for carbon dioxide (CO2) permeation and separation was assessed to determine the capability of the DES-impregnated membrane. The outcomes demonstrating that the highest loading of DES in the membrane support was obtained when 3 wt% PEG was added into the polymer solution with a porosity of 70.5%. The CO2 permeability and the CO2/N2 selectivity achieved using the synthesized membrane are 2.81 x 106 barrer and 3.46, respectively, when working with a transmembrane pressure of 1.1 bar and a temperature of 25ᵒC at 200 cm3 /min of gas flow rate. The results showed that additional of PEG as a pore additives able to load the highest DES in the membrane pore and resulted the best CO2 permeability and the CO2/N2 selectivity.
Derivation of a Closed Form Expression for Estimating the Reduced Flow Rate for Pressure Driven Rarefied Gas Flow Through Circular Nano/Micro Pores
Authors: Hashemifard Seyed Abdollatif , Matsuura Takeshi
Published: July 2021

In this paper, a new model to predict the gas flow rate through short tubes under rarefied condition based on the sigmoidal bahaviour of gas reduced flow rate (W) versus the rarefaction parameter (d) under rarefied condition was developed. The data produced by Varoutis et al. via Direct Simulation Monte Carlo (DSMC) method were utilised to obtain the model coefficients as functions of tube length to radius (w) and pressure ratio (Pr). Then, the model was tested against the published experimental data.There was a high degree of agreement between the model predictions and the experimental data. Moreover, the new model was capable to predict the reduced flow rate of rarefied systems, not only at free molecular region and hydrodynamic region, but also at transition region, hence covering all the Knudsen number domain within the utilised data. Therefore, the proposed model was capable to make predictions as well as meet all the criteria of the rarefied gas flow within the following conditions: 0<Pr<0.9, 0.01<d<1000 and 0.0<w<20. Thus, the proposed model provides a useful tool to make a valid prediction of  the rarefied gas flow behavior in a wide range of gas transport regime.
Challenges in Membrane Process for Gas Separation from Natural Gas
Authors: Farahdila K. , Goh P. S. , Ismail A. F. , Wan N. F. W. M. , Mohd H. M. H. , Soh W. K. , Yeo S. Y.
Published: July 2021

Membrane technology is cost effective solution for CO2 removal from natural gas. However, there is challenges during its application depending on the polymer material characteristic. Understanding on the polymer fundamental and transport properties, will enable proper design of pre-treatment and operating conditions that suits its capability envelope. Diffusivity selective membrane favors high pressure and high temperature conditions and vice versa for solubility selective polymer. On top of that, the robustness and durability of the resultant membrane, need to be evaluated with multicomponent mixture to understand the effect of competitive sorption, plasticization and aging phenomena that will seriously impacting the membrane performance during its application.
The role of early visual experience in the development of spatial‐frequency preference in the primary visual cortex
Authors: Nishio Nana , Hayashi Kenji , Ishikawa Ayako Wendy , Yoshimura Yumiko
Published: July 2021

Key points

The mature functioning of the primary visual cortex depends on postnatal visual experience, while the orientation/direction preference is established just after eye‐opening, independently of visual experience.

In this study, we find that visual experience is required for the normal development of spatial‐frequency (SF) preference in mouse primary visual cortex.

We show that age‐ and experience‐dependent shifts in optimal SFs towards higher frequencies occurred similarly in excitatory neurons and parvalbumin‐positive interneurons.

We also show that some excitatory and parvalbumin‐positive neurons preferentially responded to visual stimuli consisting of very high SFs and posterior directions, and that the preference was established at earlier developmental stages than the SF preference in the standard frequency range.

These results suggest that early visual experience is required for the development of SF representation and shed light on the experience‐dependent developmental mechanisms underlying visual cortical functions.

Early visual experience is crucial for the maturation of visual cortical functions. It has been demonstrated that the orientation and direction preferences in individual neurons of the primary visual cortex are well established immediately after eye‐opening. The postnatal development of spatial frequency (SF) tuning and its dependence on visual experience, however, has not been thoroughly quantified. In this study, macroscopic imaging with flavoprotein autofluorescence revealed that the optimal SFs shift towards higher frequency values during normal development in mouse primary visual cortex. This developmental shift was impaired by binocular deprivation during the sensitive period, postnatal 3 weeks (PW3) to PW6. Furthermore, two‐photon Ca2+ imaging revealed that the developmental shift of the optimal SFs, depending on visual experience, concurrently occurs in excitatory neurons and parvalbumin‐positive inhibitory interneurons (PV neurons). In addition, some excitatory and PV neurons exhibited a preference for visual stimuli consisting of particularly high SFs and posterior directions at relatively early developmental stages; this preference was not affected by binocular deprivation. Thus, there may be two distinct developmental mechanisms for the establishment of SF preference depending on the frequency values. After PW3, SF tuning for neurons tuned to standard frequency ranges was sharper in excitatory neurons and slightly broader in PV neurons, leading to considerably attenuated SF tuning in PV neurons compared to excitatory neurons by PW5. Our findings suggest that early visual experience is far more important than orientation/direction selectivity for the development of the neural representation of the diverse SFs.
Energy Content Characterization of Water Waves Using Linear and Nonlinear Spectral Analysis
Authors: Mohtat Ali , Yim Solomon C. , Osborne Alfred R.
Published: July 2021

The survivability, safe operation, and design of marine vehicles and wave energy converters are highly dependent on accurate characterization and estimation of the energy content of the ocean wave field. In this study, analytical solutions of the nonlinear Schrödinger equation (NLS) using periodic inverse scattering transformation (IST) and its associated Riemann spectrum are used to obtain the nonlinear wave modes (eigen functions of the nonlinear equation consisting of multiple phase-locked harmonic components). These nonlinear wave modes are used in two approaches to develop a more accurate definition of the energy content. First, in an ad hoc approach, the amplitudes of the nonlinear wave modes are used with a linear energy calculation resulting in a semi-linear energy estimate. Next, a novel, mathematically exact definition of the energy content taking into account the nonlinear effects up to fifth order is introduced in combination with the nonlinear wave modes, the exact energy content of the wave field is computed. Experimental results and numerical simulations were used to compute and analyze the linear, ad hoc, and exact energy contents of the wave field, using both linear and nonlinear spectra. The ratio of the ad hoc and exact energy estimates to the linear energy content was computed to examine the effect of nonlinearity on the energy content. In general, an increasing energy ratio was observed for increasing nonlinearity of the wave field, with larger contributions from higher-order harmonic terms. It was confirmed that the significant increase in nonlinear energy content with respect to its linear counterpart is due to the increase in the number of nonlinear phase-locked (bound wave) modes.2
Radiation Modes of Propeller Tonal Noise
Authors: Jiang Hanbo , Zhong Siyang , Wu Han , Zhang Xin , Huang Xun , Zhou Guocheng , Chen Bao
Published: July 2021

This paper focuses on the radiation modes and efficiency of propeller tonal noise. The thickness noise and loading noise model of propellers has been formulated in spherical coordinates, thereby simplifying numerical evaluation of the integral noise source. More importantly, the radiation field can be decomposed and projected to spherical harmonics, which can separate source-observer positions and enable an analysis of sound field structures. Due to the parity of spherical harmonics, the proposed model can mathematically explain the fact that thrusts only produce antisymmetric sound waves with respect to the rotating plane. In addition, the symmetric components of the noise field can be attributed to the thickness, as well as drags and radial forces acting on the propeller surface. The radiation efficiency of each mode decays rapidly as noise sources approach the rotating center, suggesting the radial distribution of aerodynamic loadings should be carefully designed for low-noise propellers. The noise prediction model has been successfully applied to a drone propeller and achieved a reliable agreement with experimental measurements. The flow variables employed as an input of the noise computation were obtained with computational fluid dynamics (CFD), and the experimental data were measured in an anechoic chamber.
Constituent and Ply-Level Understanding of Electrical Resistance in Si-Containing SiC/SiC Composites
Authors: Rassi Joseph El , Morscher Gregory N.
Published: July 2021

Electrical resistance (ER), also known as direct current potential drop, has been demonstrated as an enabling means to monitor damage evolution in SiC-based ceramic matrix composites (CMCs). For laminate composites, it has become apparent that the location and orientation of SiC fibers, free Si, and in some cases insertion of C rods can greatly affect the measured resistance. In addition, the nature of crack growth through the different plies which consist of different constituents will have different effects on the change in resistance. Therefore, both experimental and modeling approaches as to the resistance and change in resistance for different laminate architectures based on the nature of constituent content and orientation are needed to utilize and optimize ER as a health-monitoring technique. In this work, unidirectional and cross-ply laminate composites have been analyzed using a ply-based electrical model. Based on a ply-level circuit model, the change in resistance was modeled for damage development. It is believed that this can serve as a basis for tailoring the architecture/constituent content to create a “smarter” composite.
Fuel Economy Results From Diesel Engine Tuning for Steady Speed and Drive Cycle Operation
Authors: Satorre James Carl M. , Quiros Edwin N. , Mercado Jose Gabriel E. , Rodgers Paul L.
Published: July 2021

As part of efforts to mitigate climate change by reducing fuel consumption in the transport sector in the Philippines, this paper presents the initial results of an investigation on the effects of engine tuning on fuel economy for different drive cycles using a commercially available piggyback tuning “chip” to modify fuel rail pressure from stock settings of a CRDI diesel passenger van. The drive cycles used in this study were the Japanese 10-15 Mode, US highway fuel economy test (HWFET), and one labeled “SMN” based on a Metro Manila local route. An initial steady state vehicle fuel economy performance map at five speeds per gear position and stock tuning was obtained from chassis dynamometer tests. The same series of tests were done with the tuning chip’s settings of progressively lower rail pressure to identify the setting giving lowest fuel consumption at each gear. Fuel consumption reduction of up to 47% was observed although not all speeds at a given gear and tuning setting gave reduced values. These lowest fuel settings were applied to corresponding gear positions in each of the selected drive cycles resulting to “specific tuning maps” per drive cycle. The test vehicle was then driven with these drive cycle-specific tuning maps and the fuel economy measured. It was found that overall fuel economy decreased with drive cycle-specific tuning settings.

It was then decided to try using a constant tuning setting throughout a drive cycle to see if fuel economy improved. Trials with the Japanese 10-15 Mode cycle at different constant lower rail pressure settings likewise gave overall lower fuel economy. However, a more detailed look showed that in the constant-speed portions of the cycle, fuel consumption savings of up to 35% were realized while it worsened in the accelerating and decelerating sections.

The drive cycle test results indicate that the engine ECU compensated for the lowered rail pressure, maybe with increased injection duration, to increase the amount of fuel injected to meet the road-load requirements imposed by the drive cycle. Control response instabilities may have also contributed to higher fuel consumption. Engine tuning by rail pressure reduction only was most effective in reducing fuel consumption for steady state driving and ineffective for transient driving under the conditions and methodology of this study.
An Assessment of Thermal Comfort for Thermoelectric-Based Radiant Cooling Systems: A Numerical Investigation
Authors: Seyednezhad Mohadeseh , Najafi Hamidreza
Published: July 2021

Studying various innovative cooling/heating technologies as alternatives to vapor-compression refrigeration cycles has received growing attention over the last few years. Thermoelectric (TE) systems are among the promising emerging technologies in this category. In the present paper, numerical modeling and analysis is performed using COMSOL Multiphysics to assess the performance of a thermoelectric (TE)-based radiant cooling ceiling panel on the thermal comfort in a test chamber. The system consists of a rectangular test chamber (∼ 1.2 m × 1.2 m × 1.5 m) with a ceiling panel fabricated on the center of the ceiling (0.6 m × 0.6 m × 0.002 m). Four TE modules are installed on the backside of the ceiling panel producing a cooling effect to maintain the ceiling temperature at the desired level. The lowered temperature of the ceiling panel allows heat exchange through radiation and convection. A spherical object is used to model a globe thermometer (GT) and capture the mean radiant temperature inside of the chamber. The variation of mean radiant temperature and operative temperature versus time are assessed under natural convection, and the comfort level is evaluated using the PMV method based on ASHRAE Standard 55. Design challenges, such as temperature limitation to the dew point temperature, among others, will be discussed. The result of this study provides insights regarding the expected thermal comfort from TE-based radiant cooling systems under various conditions.
Seismic detection of the martian core
Authors: Stähler Simon C. , Khan Amir , Banerdt W. Bruce , Lognonné Philippe , Giardini Domenico , Ceylan Savas , Drilleau Mélanie , Duran A. Cecilia , Garcia Raphaël F. , Huang Quancheng , Kim Doyeon , Lekic Vedran , Samuel Henri , Schimmel Martin , Schmerr Nicholas , Sollberger David , Stutzmann Éléonore , Xu Zongbo , Antonangeli Daniele , Charalambous Constantinos , Davis Paul M. , Irving Jessica C. E. , Kawamura Taichi , Knapmeyer Martin , Maguire Ross , Marusiak Angela G. , Panning Mark P. , Perrin Clément , Plesa Ana-Catalina , Rivoldini Attilio , Schmelzbach Cédric , Zenhäusern Géraldine , Beucler Éric , Clinton John , Dahmen Nikolaj , van Driel Martin , Gudkova Tamara , Horleston Anna , Pike W. Thomas , Plasman Matthieu , Smrekar Suzanne E.
Published: July 2021

Single seismometer structure

Because of the lack of direct seismic observations, the interior structure of Mars has been a mystery. Khan
et al.
, Knapmeyer-Endrun
et al.
, and Stähler
et al.
used recently detected marsquakes from the seismometer deployed during the InSight mission to map the interior of Mars (see the Perspective by Cottaar and Koelemeijer). Mars likely has a 24- to 72-kilometer-thick crust with a very deep lithosphere close to 500 kilometers. Similar to the Earth, a low-velocity layer probably exists beneath the lithosphere. The crust of Mars is likely highly enriched in radioactive elements that help to heat this layer at the expense of the interior. The core of Mars is liquid and large, ∼1830 kilometers, which means that the mantle has only one rocky layer rather than two like the Earth has. These results provide a preliminary structure of Mars that helps to constrain the different theories explaining the chemistry and internal dynamics of the planet.

Science
, abf2966, abf8966, abi7730, this issue p.
434
, p.
438
, p.
443
see also abj8914, p.
388
Draft Genome Sequence of Aeromonas popoffii ID682, Isolated from a Natural Water Source in Idaho
Authors: Testerman Todd , Reichley Stephen R. , King Stacy , Graf Joerg
Published: July 2021

A draft genome sequence of
Aeromonas popoffii
ID682, isolated from a natural water source in Idaho, is presented here.
A. popoffii
is a relatively understudied species within a diverse, expanding freshwater genus of bacteria. Here, we describe only the second genome published for this species to date.
Complete Genome Sequence of
Effusibacillus
sp. Strain skT53, Isolated from Farm Soil
Authors: Konishi Tomoyuki , Tamura Tomohiko , Tobita Toru , Sakai Saori , Matsuda Namio , Kawasaki Hisashi
Published: July 2021

This study reports the complete genome sequence of
Effusibacillus
sp. strain skT53. The genome is 3,454,394 bp in length and has a G+C content of 48.22 mol%.
The Near Islands (the Aleutian Arc): History of Vegetation in the Holocene
Authors: Smyshlyaeva O. I. , Severova E. E. , Khasanov B. F. , Krylovich O. A. , Kuzmicheva E. A. , Savinetsky A. B.
Published: July 2021

Abstract—

The vegetation history of the Alсan Creek peat deposit on Shemya Island (the Near Islands of the Aleutian Arc) has been reconstructed. We chose this flat island because there are no volcanoes on it and they have less impact on the vegetation. The sedge tundra dominated until 7000 years ago. Then it was replaced by mire with a noticeable participation of Sphagnum and Equisetum during the Holocene warming maximum 7000–5000 years ago. Forb sedge-grass meadows spread about 4700 years ago as a result of a local change in humidity. As a consequence of cooling and leaching processes, heather tundra began to dominate in the inner part of the island about 3400 years ago.
New phenotype caused by POMGNT2 mutations
Authors: Cassone Marco , Fiorillo Chiara , Zara Federico , Vitali Carlo
Published: July 2021

We present a case report about a Moroccan 3-year-old girl, with an intermediate phenotype of muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A, 8 form. We performed clinical and instrumental evaluation, muscle biopsy, genetic screening of 59 genes for different cerebral malformations, follow-up and review of literature. After investigations, we identified an intermediate new phenotype between the severe and mild form, characterised by significant malformations of the cortex with myopatic symptoms, this increases the genotype–phenotype correlation knowledge about POMGNT2 gene mutations. New homozygous missense mutation on POMGNT2 (c.511 G>A, p.Asp171Asn, rs768063378) was detected.
Treating pain related to Ehlers-Danlos syndrome with medical cannabis
Authors: Dar Sabeera
Published: July 2021

We present the case of an 18-year-old woman who suffered from complications of Ehlers-Danlos syndrome (EDS). Her pain was poorly controlled despite being on a myriad of analgesic medications at the time. On initiating cannabinoid-based treatment, her pain was drastically reduced, immediately enhancing the patient’s quality of life. As the patient continued to self-administer, she was able to eliminate her opioid requirement. Considering the recent legalisation, we underline the need for physicians to be educated regarding the use of cannabinoids. In this case, specifically for chronic pain stemming from hypermobile EDS. Furthermore, we review the various impediments preventing ease of access to this potentially beneficial treatment.
Wide-field optical coherence tomography deviation map for early glaucoma detection
Authors: Kim Hyungjun , Park Hae Min , Jeong Hyo Chan , Moon So Yeon , Cho Hyunsoo , Lim Han Woong , Seong Mincheol , Park Junhong , Lee Won June
Published: July 2021

Background/aims

This study aimed to establish a wide-field optical coherence tomography (OCT) deviation map obtained from swept-source OCT (SS-OCT) scans. Moreover, it also aimed to compare the diagnostic ability of this wide-field deviation map with that of the peripapillary and macular deviation maps currently being used for the detection of early glaucoma (EG).

Methods

Four hundred eyes, including 200 healthy eyes and 200 eyes with EG were enrolled in this retrospective observational study. Patients underwent a comprehensive ocular examination, including wide-field SS-OCT (DRI-OCT Triton; Topcon, Tokyo, Japan). The individual wide-field scan was converted into a uniform template using the fovea and optic disc centres as fixed landmarks. Subsequently, the wide-field deviation map was obtained via the comparison between individual wide-field data and a normative wide-field database that had been created by combining images of healthy eyes into a uniform template in a previous study. The ability of the new wide-field deviation map to distinguish between EG and healthy eyes was assessed by comparing it with conventional deviation maps based on the area under the receiver operating characteristic curve (AUC).

Results

The wide-field deviation map obtained using the normative wide-field database showed the highest diagnostic ability for the diagnosis of EG (AUC=0.980 and 961 for colour-coded pixels presenting <5% and <1%, respectively) among various deviation maps. Its AUC was significantly superior to that of most conventional deviation maps (p<0.05). The wide-field deviation map demonstrated early structural glaucomatous damage well over a wider area.

Conclusion

The wide-field SS-OCT deviation map exhibited good performance for distinguishing between eyes with EG and healthy eyes. The visualisation of the wider damaged area on the wide-field deviation map could be useful for the diagnosis of EG in clinical settings.
Associations of ultrafine and fine particles with childhood emergency room visits for respiratory diseases in a megacity
Authors: Fang Jiakun , Song Xiaoming , Xu Hongbing , Wu Rongshan , Song Jing , Xie Yunfei , Xu Xin , Zeng Yueping , Wang Tong , Zhu Yutong , Yuan Ningman , Jia Jinzhu , Xu Baoping , Huang Wei
Published: July 2021

Background

Ambient fine particulate matter with aerodynamic diameter less than 2.5 µm (PM2.5) has been associated with deteriorated respiratory health, but evidence on particles in smaller sizes and childhood respiratory health has been limited.

Methods

We collected time-series data on daily respiratory emergency room visits (ERVs) among children under 14 years old in Beijing, China, during 2015–2017. Concurrently, size-fractioned number concentrations of particles in size ranges of 5–560 nm (PNC5–560) and mass concentrations of PM2.5, black carbon (BC) and nitrogen dioxide (NO2) were measured from a fixed-location monitoring station in the urban area of Beijing. Confounder-adjusted Poisson regression models were used to estimate excessive risks (ERs) of particle size fractions on childhood respiratory ERVs, and positive matrix factorisation models were applied to apportion the sources of PNC5–560.

Results

Among the 136 925 cases of all-respiratory ERVs, increased risks were associated with IQR increases in PNC25–100 (ER=5.4%, 95% CI 2.4% to 8.6%), PNC100–560 (4.9%, 95% CI 2.5% to 7.3%) and PM2.5 (1.3%, 95% CI 0.1% to 2.5%) at current and 1 prior days (lag0–1). Major sources of PNC5–560 were identified, including nucleation (36.5%), gasoline vehicle emissions (27.9%), diesel vehicle emissions (18.9%) and secondary aerosols (10.6%). Emissions from gasoline and diesel vehicles were found of significant associations with all-respiratory ERVs, with increased ERs of 6.0% (95% CI 2.5% to 9.7%) and 4.4% (95% CI 1.7% to 7.1%) at lag0–1 days, respectively. Exposures to other traffic-related pollutants (BC and NO2) were also associated with increased respiratory ERVs.

Conclusion

Our findings suggest that exposures to higher levels of PNC5–560 from traffic emissions could be attributed to increased childhood respiratory morbidity, which supports traffic emission control priority in urban areas.
Algebraic structure of Dirac–Pauli equation with account to AMM of neutron in the presence of magnetic field with cylindrical symmetry
Authors: Seidi Masoud
Published: July 2021

The eigenvalues and eigenfunctions of Dirac–Pauli equation have been obtained for a neutron with anomalous magnetic moment (AMM) in the presence of a strong magnetic field with cylindrical symmetry. In our calculations, the Nikiforov and Uvarov (NU) method has been used. Using the eigenfunctions and construction of the ladder operators, we show that these generators satisfy su(2) Lie algebra and computed the second-order Casimir operator of the lie algebra.
Temperature fluctuations and Tsallis statistics in relativistic heavy ion collisions
Authors: Saha Abhisek , Sanyal Soma
Published: July 2021

In this paper, we study temperature fluctuations in the initial stages of the relativistic heavy ion collision using a multiphase transport model. We consider the plasma in the initial stages after collision before it has a chance to equilibrate. We have considered [Formula: see text] collision with a center-of-mass energy of 200 GeV. We use the nonextensive Tsallis statistics to find the entropic index in the partonic stages of the relativistic heavy ion collisions. We find that the temperature and the entropic index have a linear relationship during the partonic stages of the heavy ion collision. This has already been observed in the hadronic phase. A detailed analysis of the dependence of the entropic index on the system shows that for increasing spacetime rapidity, the entropic index of the partonic system increases. The entropic index also depends on the beam collision energy. The calculation of the entropic index from the experimental data fitting of the transverse momenta deals with the hadronic phase. However, our study shows that the behavior of the entropic index in the initial nonequilibrium stage of the collision is very similar to the behavior of the entropic index in the hadronic stage.
Quantum corrected thermodynamics of nonlinearly charged BTZ black holes in massive gravity’s rainbow
Authors: Dehghani M. , Pourhassan B.
Published: July 2021

In this paper, we consider three-dimensional massive gravity’s rainbow and obtain black hole solutions in three different cases of Born–Infeld, logarithmic, and exponential theories of nonlinear electrodynamics. We discuss the horizon structure and geometrical properties. Then, we study thermodynamics of these models by considering the first-order quantum correction effects, which appear as a logarithmic term in the black hole entropy. We discuss such effects on the black hole stability and phase transitions. We find that due to the quantum corrections, the second-order phase transition happens in Born–Infeld and logarithmic models. We obtain the modified first law of black hole thermodynamics in the presence of logarithmic corrections.
Distributed and Robust Support Vector Machine
Authors: Liu Yangwei , Ding Hu , Huang Ziyun , Xu Jinhui
Published: July 2021

In this paper, we consider the distributed version of Support Vector Machine (SVM) under the coordinator model, where all input data (i.e., points in [Formula: see text] space) of SVM are arbitrarily distributed among [Formula: see text] nodes in some network with a coordinator which can communicate with all nodes. We investigate two variants of this problem, with and without outliers. For distributed SVM without outliers, we prove a lower bound on the communication complexity and give a distributed [Formula: see text]-approximation algorithm to reach this lower bound, where [Formula: see text] is a user specified small constant. For distributed SVM with outliers, we present a [Formula: see text]-approximation algorithm to explicitly remove the influence of outliers. Our algorithm is based on a deterministic distributed top [Formula: see text] selection algorithm with communication complexity of [Formula: see text] in the coordinator model.
Theoretical and experimental study of new nonlinear optical material nicotinohydrazide
Authors: Deepa C. , Anbuchezhiyan M. , Sribalan Rajendran
Published: July 2021

Pyridine-3-carbohydrazide (NIH) crystal is grown by slow evaporation solution growth technique and the single crystal X-ray diffraction experiment confirms cell parameters and space group. The FT-IR and FT-Raman studies are used to identify the functional groups in the compound Nicotinohydrazide. The thermal studies are conducted using thermogravimetric analysis and differential thermal analysis, the UV–Visible transmission spectrum of NIH is recorded within the range of 400–800[Formula: see text]nm. Besides, in order to know the optical properties of the material at molecular level, density functional theory (DFT) has been employed using B3LYP method at 6-[Formula: see text] (d,p). The electric dipole moment and first-order hyperpolarizability are calculated and found to be high. The second-order NLO studies for NIH crystal are done and it is compared with KDP.
THE VALUE OF BEING LUCKY: OPTION BACKDATING AND NONDIVERSIFIABLE RISK
Authors: HENDERSON VICKY , SUN JIA , WHALLEY A. ELIZABETH
Published: July 2021

The practice of executives influencing their option compensation by setting a grant date retrospectively is known as backdating. Since executive stock options are usually granted at-the-money, selecting an advantageous grant date to coincide with a low stock price will be valuable to an executive. Empirical evidence shows that backdating of executive stock option grants was prevalent, particularly at firms with highly volatile stock prices. Executives who have the opportunity to backdate should take this into account in their valuation. We quantify the value to a risk averse executive of a lucky option grant with strike chosen to coincide with the lowest stock price of the month. We show the ex ante gain to risk averse executives from the ability to backdate increases with both risk aversion and with volatility, and is significant in magnitude. Our model involves valuing the embedded partial American lookback option in a utility indifference setting with key features of risk aversion, inability to diversify and early exercise.
A Manipulation Game Based on Machiavellian Strategies
Authors: Clempner Julio B.
Published: July 2021

This paper suggests a manipulation game based on Machiavellianism, which is characterized by three concepts: views, tactics, and immorality. We consider a framework where manipulating players can partially control manipulated players’ information and affect both manipulated players’ information and their allocations. The parties involved are constrained both by adverse selection and moral hazard (immorality) restricted to a class of ergodic Bayesian–Markov problems. We investigate a mechanism that maximize the probability that the manipulated players accept the proposal of the manipulators. We show that a mechanism exists and can be found by solving a nonlinear programming problem for a set of constraints. The mechanism is obtained by introducing an auxiliary variable in the nonlinear programming problem and we develop the relations needed to derive the variables of interest. For the manipulation process, players learn their behavior through a sequence of interactions in a repeated game. The manipulators possess and benefit from some commitment power, which describes the distinctive nature of a manipulation game (views). Then, we represent the game using a Stackelberg model. We also compute the Stackelberg equilibrium (tactics) for our game of incomplete information. This novel perspective is of interest for the Bayesian manipulation and persuasion literature. A simulation and analysis over an example for manipulating emotions in negotiation verify the applicability of proposed model.
Outer-connected open packing sets in graphs
Authors: Saravanakumar S. , Gayathri C.
Published: July 2021

A set [Formula: see text] of a graph [Formula: see text] is an [Formula: see text] [Formula: see text] [Formula: see text] of [Formula: see text] if no two vertices of [Formula: see text] have a common neighbor in [Formula: see text]. An open packing set [Formula: see text] is called an outer-connected open packing set (ocop-set) if either [Formula: see text] or [Formula: see text] is connected. The minimum and maximum cardinalities of an ocop-set are called the lower outer-connected open packing number and the outer-connected open packing number, respectively, and are denoted by [Formula: see text] and [Formula: see text], respectively. In this paper, we initiate a study on these parameters.
Arithmetic progressions in finite groups
Authors: Tărnăuceanu Marius
Published: July 2021

In this paper, we describe the structure of finite groups whose element orders or proper (abelian) subgroup orders form an arithmetic progression of ratio [Formula: see text]. This extends the case [Formula: see text] studied in previous papers [R. Brandl and W. Shi, Finite groups whose element orders are consecutive integers, J. Algebra 143 (1991) 388–400; Y. Feng, Finite groups whose abelian subgroup orders are consecutive integers, J. Math. Res. Exp. 18 (1998) 503–506; W. Shi, Finite groups whose proper subgroup orders are consecutive integers, J. Math. Res. Exp. 14 (1994) 165–166].
On H-irregularity strength of cycles and diamond graphs
Authors: Labane Hayat , Bouchemakh Isma , Semaničová-Feňovčíková Andrea
Published: July 2021

A simple graph [Formula: see text] admits an [Formula: see text]-covering if every edge in [Formula: see text] belongs to at least one subgraph of [Formula: see text] isomorphic to a given graph [Formula: see text]. The graph [Formula: see text] admits an [Formula: see text]-irregular total [Formula: see text]-labeling [Formula: see text] if [Formula: see text] admits an [Formula: see text]-covering and for every two different subgraphs [Formula: see text] and [Formula: see text] isomorphic to [Formula: see text], there is [Formula: see text], where [Formula: see text] is the associated [Formula: see text]-weight. The total [Formula: see text]-irregularity strength of [Formula: see text] is [Formula: see text].

In this paper, we give the exact values of [Formula: see text], where [Formula: see text]. For the versions edge and vertex [Formula: see text]-irregularity strength [Formula: see text] and [Formula: see text], respectively, we determine the exact values of [Formula: see text], [Formula: see text] and [Formula: see text], where [Formula: see text] is the diamond graph.
A note on global dominator coloring of graphs
Authors: Rangarajan R. , Kalarkop David. A.
Published: July 2021

Global dominator coloring of the graph [Formula: see text] is the proper coloring of [Formula: see text] such that every vertex of [Formula: see text] dominates atleast one color class as well as anti-dominates atleast one color class. The minimum number of colors required for global dominator coloring of [Formula: see text] is called global dominator chromatic number of [Formula: see text] denoted by [Formula: see text]. In this paper, we characterize trees [Formula: see text] of order [Formula: see text] [Formula: see text] such that [Formula: see text] and also establish a strict upper bound for [Formula: see text] for a tree of even order [Formula: see text] [Formula: see text]. We construct some family of graphs [Formula: see text] with [Formula: see text] and prove some results on [Formula: see text]-partitions of [Formula: see text] when [Formula: see text].
Physical experiments in geomorphology
Authors: Church Michael
Published: July 2021

An experiment is a programme of observations specially constructed to provide a critical test of theory or generalization about nature. It is designed to acquire firm evidence for or against the effect in question. Accordingly, it must be arranged to control all sources of variability contributing to the phenomena under examination, save those it is intended to study. In the natural environment, this is difficult to achieve. Consequently, classical geomorphology had no established tradition of experimentation. However, in the latter third of the twentieth century, geomorphologists began to explore experimentation as a means to resolve questions that arise in the study of geomorphological processes. In the period 1976–84, an IGU Commission on Field Experiments in Geomorphology formally established an interest in the approach. Although few field studies before the turn of the century achieved experimental status, valuable experience was gained in laboratory experiments, scaled and unscaled, leading to present wide acceptance of experimentation as a means to approach questions about geomorphological processes.
AI-empowered IoT Security for Smart Cities
Authors: Lv Zhihan , Qiao Liang , Kumar Singh Amit , Wang Qingjun
Published: July 2021

Smart cities fully utilize the new generation of Internet of Things (IoT) technology in the process of urban informatization to optimize the urban management and service. However, in the IoT system, while information exchange and communication, wireless sensor network devices may not be able to resist all forms of attacks, which may lead to security issues such as user data disclosure. Aiming at the information security risks in smart city, the typical technologies in IoT is analyzed from the perspective of IoT perception layer and provides corresponding security solutions for the existing security threats. Regarding the communication security, the emerging wireless technology, long range (LoRa), is discussed, and the performance of wireless communication protocol is analyzed through simulation experiments, to verify that the IoT technology based on LoRa communication technology can improve the security of the system in the construction of smart city. The results show that REBEB, a new backoff algorithm, is similar to the binary exponential backoff algorithm in terms of throughput performance. REBEB focuses more on fairness, which is up to 0.985, and to a certain extent, its security is significantly improved. The fairness of REBEB algorithm is more than 0.4 in different nodes and competing windows, and the fairness of the system is better when the number of nodes is small. To sum up, the IoT system based on LoRa communication can effectively improve the security performance of the system in the construction of smart city and avoid the security threats in the IoT signal transmission.
A Secure Ticket-Based Authentication Mechanism for Proxy Mobile IPv6 Networks in Volunteer Computing
Authors: Alizadeh Mojtaba , Tadayon Mohammad Hesam , Sakurai Kouichi , Anada Hiroaki , Jolfaei Alireza
Published: July 2021

Technology advances—such as improving processing power, battery life, and communication functionalities—contribute to making mobile devices an attractive research area. In 2008, in order to manage mobility, the Internet Engineering Task Force (IETF) developed Proxy Mobile IPv6, which is a network-based mobility management protocol to support seamless connectivity of mobile devices. This protocol can play a key role in volunteer computing paradigms as a user can seamlessly access computing resources. The procedure of user authentication is not defined in this standard; thus, many studies have been carried out to propose suitable authentication schemes. However, in the current authentication methods, with reduced latency and packet loss, some security and privacy considerations are neglected. In this study, we propose a secure and anonymous ticket-based authentication (SATA) method to protect mobile nodes against existing security and privacy issues. The proposed method reduces the overhead of handover authentication procedures using the ticket-based concept. We evaluated security and privacy strengths of the proposed method using security theorems and BAN logic.
An Incentive-based Mechanism for Volunteer Computing Using Blockchain
Authors: Al Ridhawi Ismaeel , Aloqaily Moayad , Jararweh Yaser
Published: July 2021

The rise of fast communication media both at the core and at the edge has resulted in unprecedented numbers of sophisticated and intelligent wireless IoT devices. Tactile Internet has enabled the interaction between humans and machines within their environment to achieve revolutionized solutions both on the move and in real-time. Many applications such as intelligent autonomous self-driving, smart agriculture and industrial solutions, and self-learning multimedia content filtering and sharing have become attainable through cooperative, distributed, and decentralized systems, namely, volunteer computing. This article introduces a blockchain-enabled resource sharing and service composition solution through volunteer computing. Device resource, computing, and intelligence capabilities are advertised in the environment to be made discoverable and available for sharing with the aid of blockchain technology. Incentives in the form of on-demand service availability are given to resource and service providers to ensure fair and balanced cooperative resource usage. Blockchains are formed whenever a service request is initiated with the aid of fog and mobile edge computing (MEC) devices to ensure secure communication and service delivery for the participants. Using both volunteer computing techniques and tactile internet architectures, we devise a fast and reliable service provisioning framework that relies on a reinforcement learning technique. Simulation results show that the proposed solution can achieve high reward distribution, increased number of blockchain formations, reduced delays, and balanced resource usage among participants, under the premise of high IoT device availability.
Transfer Reinforcement Learning for Autonomous Driving
Authors: Balakrishnan Aravind , Lee Jaeyoung , Gaurav Ashish , Czarnecki Krzysztof , Sedwards Sean
Published: July 2021

Reinforcement learning (RL) is an attractive way to implement high-level decision-making policies for autonomous driving, but learning directly from a real vehicle or a high-fidelity simulator is variously infeasible. We therefore consider the problem of transfer reinforcement learning and study how a policy learned in a simple environment using
WiseMove
can be transferred to our high-fidelity simulator, W
ise
M
ove
.
WiseMove
is a framework to study safety and other aspects of RL for autonomous driving. W
ise
M
ove
accurately reproduces the dynamics and software stack of our real vehicle.

We find that the accurately modelled perception errors in W
ise
M
ove
contribute the most to the transfer problem. These errors, when even naively modelled in
WiseMove
, provide an RL policy that performs better in W
ise
M
ove
than a hand-crafted rule-based policy. Applying domain randomization to the environment in
WiseMove
yields an even better policy. The final RL policy reduces the failures due to perception errors from 10% to 2.75%. We also observe that the RL policy has significantly less reliance on velocity compared to the rule-based policy, having learned that its measurement is unreliable.
Kripke Semantics for Intersection Formulas
Authors: Dudenhefner Andrej , Urzyczyn Paweł
Published: July 2021

We propose a notion of the Kripke-style model for intersection logic. Using a game interpretation, we prove soundness and completeness of the proposed semantics. In other words, a formula is provable (a type is inhabited) if and only if it is forced in every model. As a by-product, we obtain another proof of normalization for the Barendregt–Coppo–Dezani intersection type assignment system.
Novel Reconfigurable Hardware Systems for Tumor Growth Prediction
Authors: Malavazos Konstantinos , Papadogiorgaki Maria , Malakonakis Pavlos , Papaefstathiou Ioannis
Published: July 2021

An emerging trend in biomedical systems research is the development of models that take full advantage of the increasing available computational power to manage and analyze new biological data as well as to model complex biological processes. Such biomedical models require significant computational resources, since they process and analyze large amounts of data, such as medical image sequences. We present a family of advanced computational models for the prediction of the spatio-temporal evolution of glioma and their novel implementation in state-of-the-art FPGA devices. Glioma is a rapidly evolving type of brain cancer, well known for its aggressive and diffusive behavior. The developed system simulates the glioma tumor growth in the brain tissue, which consists of different anatomic structures, by utilizing MRI slices. The presented models have been proved highly accurate in predicting the growth of the tumor, whereas the developed innovative hardware system, when implemented on a low-end, low-cost FPGA, is up to 85% faster than a high-end server consisting of 20 physical cores (and 40 virtual ones) and more than 28× more energy-efficient than it; the energy efficiency grows up to 50× and the speedup up to 14× if the presented designs are implemented in a high-end FPGA. Moreover, the proposed reconfigurable system, when implemented in a large FPGA, is significantly faster than a high-end GPU (i.e., from 80% and up to 250% faster), for the majority of the models, while it is also significantly better (i.e., from 80% to over 1,600%) in terms of power efficiency, for all the implemented models.