bluuebunny/crossref_metadata_2025 huggingface dataset:
Hiding unhealthy heart outcomes in a low-fat diet trial: the Women’s Health Initiative Randomized Controlled Dietary Modification Trial finds that postmenopausal women with established coronary heart disease were at increased risk of an adverse outcome if they consumed a low-fat ‘heart-healthy’ diet
Authors: Noakes Timothy David
Published: July 2021

The Women’s Health Initiative Randomized Controlled Dietary Modification Trial (WHIRCDMT) was designed to test whether the US Department of Agriculture’s 1977 Dietary Guidelines for Americans protects against coronary heart disease (CHD) and other chronic diseases. The only significant finding in the original 2006 WHIRCDMT publication was that postmenopausal women with CHD randomised to a low-fat ‘heart-healthy’ diet in 1993 were at 26% greater risk of developing additional CHD events compared with women with CHD eating the control diet. A 2017 WHIRCDMT publication includes data for an additional 5 years of follow-up. It finds that CHD risk in this subgroup of postmenopausal women had increased further to 47%–61%. The authors present three post-hoc rationalisations to explain why this finding is ‘inadmissible’: (1) only women in this subgroup were less likely to adhere to the prescribed dietary intervention; (2) their failure to follow the intervention diet increased their CHD risk; and (3) only these women were more likely to not have received cholesterol-lowering drugs. These rationalisations appear spurious. Rather these findings are better explained as a direct consequence of postmenopausal women with features of insulin resistance (IR) eating a low-fat high-carbohydrate diet for 13 years. All the worst clinical features of IR, including type 2 diabetes mellitus (T2DM) in some, can be ‘reversed’ by the prescription of a high-fat low-carbohydrate diet. The Women’s Health Study has recently reported that T2DM (10.71-fold increased risk) and other markers of IR including metabolic syndrome (6.09-fold increased risk) were the most powerful predictors of future CHD development in women; blood low-density lipoprotein-cholesterol concentration was a poor predictor (1.38-fold increased risk). These studies challenge the prescription of the low-fat high-carbohydrate heart-healthy diet, at least in postmenopausal women with IR, especially T2DM. According to the medical principle of ‘first do no harm’, this practice is now shown to benotevidence-based, making it scientifically unjustifiable, perhaps unethical.
F1-taught orthopaedic teaching programme for students (FOTS)
Authors: Kumar Prakrit Raj , Hashmi Yousuf , Beedham William , Kumar Ranya Vardini , Fleming Simon
Published: July 2021

Introduction

The COVID-19 pandemic has impacted students learning, with the time off resulting in students ‘de-skilling’, increasing concerns for upcoming observed structured clinical examinations. Foundation Year 1 (F1) doctors (F1s), despite being expected to teach, rarely receive formal preparation, with COVID-19 exacerbating opportunities to practice. As such, a national orthopaedic teaching programme was designed to provide F1s with opportunities to develop their teaching skills and to synergistically teach medical students how to perform clinical orthopaedic examinations.

Methods

Six weekly sessions, each delivered by two newly qualified F1 tutors, on each joint examination were delivered online via Zoom Video Communications (USA). Presession and postsession multiple choice questions (MCQs) were provided to students to assess improvement in knowledge. Anonymous feedback forms were provided to both students and tutors.

Results

Of the 341 students that attended, 87.1% provided feedback. 86.2% felt that they had de-skilled due to time off, with a mean 15 weeks off from placement. Based on a 5-point Likert scale, students displayed a mean improvement in confidence (1.9±1.1, p<0.001) and MCQ scores (1.4±1.3, p<0.001) before and after the sessions. 91.6% and 95.3% agreed that the use of online teaching increased attendance and laid the foundation for practice. Of the six tutors, all reported improvement in confidence to teach and teaching skills.

Conclusion

We demonstrate that online delivery of clinical orthopaedic examinations is effective, increasing the knowledge and confidence of students, while providing opportunities for F1s to teach. We present our findings to encourage similar teaching programmes to be adopted at other locations and specialties, to synergistically benefit students, doctors and ultimately, patients.
Early evidence of the associations between an anti-e-cigarette mass media campaign and e-cigarette knowledge and attitudes: results from a cross-sectional study of youth and young adults
Authors: Hair Elizabeth C , Kreslake Jennifer M , Rath Jessica Miller , Pitzer Lindsay , Bennett Morgane , Vallone Donna
Published: July 2021

Objective

Antismoking mass media campaigns have contributed to significant declines in combustible tobacco use among young people. This study evaluates a national anti-e-cigarette campaign to determine its association with knowledge, attitudes and beliefs in the context of increasing e-cigarette use in the USA.

Methods

A national sample of respondents aged 15–24 years (n=8421) was drawn from a repeated cross-sectional online panel survey (220 participants/week) (October 2018 to December 2019). Self-reported exposure to the truth anti-e-cigarette campaign was measured according to level of ad awareness. Outcomes were subjective knowledge of campaign-targeted facts about e-cigarettes and attitudinal constructs about perceived e-cigarette harm, social unacceptability and anti-industry sentiments. Covariates included respondent demographics, current e-cigarette use and cigarette use, parental smoking, sensation seeking, mental health and growth in e-cigarette sales.

Results

Ad awareness was associated with knowledge that e-cigarette users are more likely to start smoking (low OR: 1.28, 95% CI 1.14 to 1.44; high OR: 1.88, 95% CI 1.66 to 2.13) and of the nicotine content of JUUL compared with cigarettes (low OR: 1.63, 95% CI 1.45 to 1.82; high OR: 2.50, 95% CI 2.21 to 2.84). High ad awareness was associated with knowledge that the long-term health effects of JUUL use are unknown (OR: 1.88, 95% CI 1.57 to 2.28). High ad awareness was associated with significantly higher perceived product harm (OR: 1.35, 95% CI 1.18 to 1.54), social unacceptability (OR: 1.32, 95% CI 1.15 to 1.53) and anti-industry attitudes (OR: 1.40, 95% CI 1.21 to 1.62), compared with respondents with no awareness.

Conclusions

Young people with awareness of anti-e-cigarette ads demonstrate higher levels of campaign-targeted knowledge, attitudes and beliefs. Future campaign evaluation priorities include measuring the campaign effects on e-cigarette use behaviours.
A mathematical model and a method to measure the instantaneous power output of vehicular driving wheels
Authors: Zhao Wei , Li Zhi-zhong , Zhang Hai-tao
Published: July 2021

The internal resistance of a dynamometer is regarded as a constant force when using traditional test methods, which means that the measurement values for the instantaneous power output of the vehicle driving wheel are underestimated. In this study, we aimed to resolve this issue. Thus, we constructed a system for measuring drum movement and propose a method for measuring the instantaneous power output of a vehicle’s driving wheel. Further, we created a mathematical model of the instantaneous power output from a vehicle’s driving wheel. Comparing the results from our model with our experimental results, we found that the actual power output of the driving wheel was reflected more accurately by our proposed method, and that the accuracy of the measurement results was not affected by the vehicle’s speed. The output torque of the vehicle’s driving wheel calculated using our proposed model was closer to the running resistance of the vehicle. Thus, our model facilitates accurate no-dismounting, rapid measurement of the power output of a driving wheel, and accurate simulation of road running resistance using a dynamometer.
A Solution Method for the Maritime Pilot Scheduling Problem with Working Hour Regulations
Authors: Xiao Liyang , Wang Zhengpei , Tan Zheyi , Wang Chenghao
Published: July 2021

Motivated by real needs of the industry, this paper studies a maritime pilot scheduling problem with working hour regulations. The existing traditional manual scheduling method of the targeted pilot station is actually a greedy-based approach which may lead to an extremely high operating cost solution and also some dissatisfaction of pilots. A mixed-integer programming (MIP)-based formulation is established and a variable neighborhood search (VNS) approach is proposed to solve the problem efficiently. Compared to the traditional scheduling method, the VNS approach significantly reduces the operating costs in different scales of realistic instances. At the same time, working time and working timespan of pilots are also prominently reduced, which hence directly reduce the workloads of pilots and improve their job satisfaction.
Emergence of a cosmological constant in anisotropic fluid cosmology
Authors: Cadoni M. , Sanna A. P.
Published: July 2021

In this paper, we investigate anisotropic fluid cosmology in a situation where the space–time metric back-reacts in a local, time-dependent way to the presence of inhomogeneities. We derive exact solutions to the Einstein field equations describing Friedmann–Lemaítre–Robertson–Walker (FLRW) large-scale cosmological evolution in the presence of local inhomogeneities and time-dependent backreaction. We use our derivation to tackle the cosmological constant problem. A cosmological constant emerges by averaging the backreaction term on spatial scales of the order of 100 Mpc, at which our universe begins to appear homogeneous and isotropic. We find that the order of magnitude of the “emerged” cosmological constant agrees with astrophysical observations and is related in a natural way to baryonic matter density. Thus, there is no coincidence problem in our framework.
Observational data analysis for generalized cosmic Chaplygin gas in the background of Brans–Dicke theory
Authors: Debnath Ujjal
Published: July 2021

In this paper, we have considered the generalized cosmic Chaplygin gas (GCCG) in the background of Brans–Dicke (BD) theory and also assumed that the Universe is filled in GCCG, dark matter and radiation. To investigate the data fitting of model parameters, we have constrained the model using recent observations. Using [Formula: see text] minimum test, the best-fit values of the model parameters are determined by OHD+CMB+BAO+SNIa joint data analysis. We have drawn the contour figures for different confidence levels [Formula: see text], [Formula: see text] and [Formula: see text]. To examine the viability of the GCCG model in BD theory, we have also determined △AIC and △BIC using the information criteria (AIC and BIC). Graphically, we have analyzed the natures of the equation of state parameter and deceleration parameter for our best-fit values of model parameters. Also, we have studied the square speed of sound [Formula: see text] which lies in the interval [Formula: see text] for expansion of the Universe. So, our considered model is classically stable by considering the best-fit values of the model parameters due to the data analysis.
Regular model of magnetized black hole with rational nonlinear electrodynamics
Authors: Kruglov S. I.
Published: July 2021

A modified Hayward metric of magnetically charged black hole space–time based on rational nonlinear electrodynamics with the Lagrangian [Formula: see text] is considered. We introduce the fundamental length, characterizing quantum gravity effects. If the fundamental length vanishes the general relativity coupling to rational nonlinear electrodynamics is recovered. We obtain corrections to the Reissner–Nordström solution as the radius approaches infinity. The metric possesses a de Sitter core without singularities as [Formula: see text]. The Hawking temperature and the heat capacity are calculated. It was shown that phase transitions occur and black holes are thermodynamically stable at some event horizon radii. We demonstrate that curvature invariants are bounded and the limiting curvature conjecture takes place.
ESTIMATION OF TWO-PHASE RELATIVE PERMEABILITIES BASED ON TREELIKE FRACTAL MODEL AND PRESSURE DROP AROUND GAS BUBBLES IN POROUS MEDIA
Authors: GU KEMING , NING ZHENGFU , MU ZHONGQI , LV FANGTAO
Published: July 2021

In order to estimate relative permeabilities of brine–gas, a semi-analytical model based on fractal theory is proposed. The model simplifies porous media as treelike nanotubes, the single nanotube’s flow has been branched out into whole pore network of core sample through treelike fractal theory. Two-phase flow description in sole nanotube, based on a setting of gas bubbles pushing continuous water phase ahead, solves pressure drop around brine and gas bubbles by Stokes’ viscous force, Laplace equation and Fairbrother–Stubbs bubble film thickness formula, Bretherton bubble pressure drop. By substituting the other three classic formulas into Bretherton expression, the iteration equation of pressure drop around a single gas bubble is acquired, the number of gas bubbles is multiplied and the gas phase pressure drop is calculated. Through merging small bubbles into a large bubble, the relative permeabilities of two phases can be solved by introducing Poiseuille’s law and Darcy’s law. After getting the fundamental data, pore size distribution data and viscosity of two phases, relative permeability curves can be drawn, revealing comprehensive elements including wettability, fluid viscosity, saturation, morphological characteristics. The calculated curves cross each other on the right half of the [Formula: see text]-axis, meet the features of real production, flowback difficulties of hydraulic liquid and well production dropping quickly, also show identical trend with experimental data. Through a series of sensitivity analysis, to some extent, the influence on relative permeabilities is compared of different fractal models, different film thickness, bubble length, water sorption layer thickness, elastic deformation of pores.
FRACTAL TREELIKE FRACTURE NETWORK MODEL FOR HYDRAULICALLY AND MECHANICALLY INDUCED DYNAMIC CHANGES IN THE NON-DARCY COEFFICIENT DURING THE PROCESS OF MINE WATER INRUSH FROM COLLAPSED COLUMNS
Authors: ZHAO JIYUAN , LIU WEITAO , SHEN JIANJUN , XU MINGHAN , SASMITO AGUS P.
Published: July 2021

An accurate and reliable mathematical model for water inrush can help ensure operational safety in coal mines. In this study, a numerical model for water inrush caused by collapsed columns that couples mechanical rock deformation with flow in porous media based on a fractal treelike fracture network was developed. In particular, the proposed model considers collapsed columns and mining damage zones as fractal dual-porosity media. The model incorporates Darcy’s law, the Brinkman equation, and the Navier–Stokes equation to govern the groundwater flow. The Brinkman equation was adopted to simulate the groundwater flow in collapsed columns, for which the non-Darcy coefficient can be derived based on damage criteria for the fracture zone. To simulate the dynamics of water inrush in collapsed columns, the finite element method was used to solve the governing equations for the groundwater flow, solid mechanics, and rock damage. The proposed model was validated against two sets of field data, and the results showed that dynamic changes in the non-Darcy coefficient could be used to identify the occurrence of water inrush, which can be employed to improve mining safety.
INSIGHTS INTO THE PREDICTABILITY AND SIMILARITY OF COVID-19 WORLDWIDE LETHALITY
Authors: FERNANDES LEONARDO H. S. , DE ARAUJO FERNANDO H. A. , SILVA JOSÉ W. L. , SILVA MARIA A. R.
Published: July 2021

This paper performs a systematic investigation into the temporal evolution of daily death cases of COVID-19 worldwide lethality considering 90 countries. We apply the information theory quantifiers, more specifically the Permutation entropy [Formula: see text] and Fisher information measure [Formula: see text] to construct the Shannon-Fisher causality plane (SFCP), which allows us to quantify the disorder and evaluate randomness present in the time series of daily death cases related to COVID-19 in each country. Moreover, we employ [Formula: see text] and [Formula: see text] to rank the COVID-19 lethality in these countries based on the complexity hierarchy. Our findings reveal that the countries that are located farther from the random ideal position ([Formula: see text], [Formula: see text]) in the SFCP such as Taiwan, Vietnam, New Zealand, Singapore, Monaco, Iceland, Thailand, Bahamas, Cyprus, Australia, and Norway are characterized by a less entropy and low disorder, which leads to high predictability of the COVID-19 lethality. Otherwise, the countries that are located near to the random ideal position ([Formula: see text], [Formula: see text]) in the SFCP such as Ecuador, Czechia, Iraq, Colombia, Belgium, Italy, Philippines, Iran, Peru, and Japan are characterized by high entropy and high disorder, which implies low predictability of the COVID-19 lethality. We also employ two cluster techniques to analyze the similarity considering the temporal evolution of COVID-19 worldwide lethality for the countries investigated. Based on the values of [Formula: see text], [Formula: see text] and our cluster analysis, we suggest that this health crisis will only be adequately combated through global adherence to scientific exchange and technology sharing to homogenize the actions to combat the COVID-19.
FURTHER DISCUSSION ABOUT FRACTIONAL DIFFERENTIABILITY OF CERTAIN CONTINUOUS FUNCTIONS
Authors: LIU N. , CAO Y. X. , YAO J.
Published: July 2021

This paper concentrates on discussing the properties of Riemann–Liouvile fractional (RLF) calculus of two special continuous functions. The first type proves the non-differentiability of a special continuous function that does not satisfy Hölder condition, and the second type uses fractal iteration to construct a fractal function defined on [Formula: see text] with unbounded variation. Then we calculate RLF integral and RLF derivative of this special function, and give the corresponding numerical calculation results and the corresponding function image.
FRACTAL MODEL OF POROUS FIN WITH TEMPERATURE-DEPENDENT HEAT GENERATION AND ITS NOVEL SOLUTION
Authors: KHAN YASIR
Published: July 2021

Porous fins with temperature-dependent internal heat generation are frequently used to improve performance in a wide range of heat transfer and porous media applications. Thermal analysis of the porous fin fractal model with temperature-dependent heat generation is generated using fractal derivatives and investigated analytically using a novel Maclaurin series method (MSM). Nonlinear temperature distribution in a porous longitudinal fin is produced by the MSM. The porous fin solution is demonstrated using the Sierpinski fractal, which is based on time-dependent heat generation. The effects of the convection parameter, porosity, internal heat production, and generation number parameter on the dimensionless temperature distribution are discussed. MSM results are graphically and tabularly compared to existing solution methods such as HPM, CM, CSCM, LWCM, and GWRM. A comparison study reveals that MSM is a very reliable, accurate, and effective addition in the field of differential equations.
AN INVESTIGATION ON SPONTANEOUS IMBIBITION IN TREE-LIKE BRANCHING NETWORK WITH FRACTAL ROUGHENED SURFACES
Authors: XIAO BOQI , LIU ZHENJIE , ZHANG YIDAN , LIANG MINGCHAO , LONG GONGBO , ZHAO ZHENG
Published: July 2021

The tree-like branching network widely exists in nature and human society. The heat and mass transfer of tree-like branching network has been studied for a long time. The research indicates that a tree-like branching network has excellent heat and mass transfer performance. In this paper, a model of spontaneous imbibition in the tree-like branching network with fractal roughened surfaces is proposed. Based on the series-parallel equivalent model, the analytical expression of the time-varying imbibition height and the expression of the equilibrium height are derived. It is found that the structural parameters of the branching network have an important influence on the imbibition process, including the diameter in the 0th branching level, the length ratio, the diameter ratio, the branching number, the total number of branching levels, the relative roughness and the branching angle. For instance, the equilibrium height increases with the increase in the total number of branching levels, but the time required to reach the equilibrium height also increases with the increase in the total number of branching levels. It is also seen that the equilibrium height increases with the increase in fractal dimension of roughened elements and length ratio, and decreases with the increase in diameter ratio. In addition, an interesting phenomenon is that the time required to reach the equilibrium height increases with the increase in branching angle, but the equilibrium height remains the same. Every parameter of the presented model has a clear physical meaning, revealing the imbibition mechanism of the tree-like branching network.
A NEW HYPERCHAOTIC COMPLEX SYSTEM WITH PARAMETRIC ATTRACTORS
Authors: ZHANG FANGFANG , LI ZHENGFENG , SUN KAI , ZHANG XUE , JI PENG
Published: July 2021

We propose a new hyperchaotic complex system. The hyperchaotic complex system has a distinctive chaotic attractor, which is called butterfly-like attractor. We find that the state of the system has a complex evolution process with the change of parameters, and the system will produce at least two kinds of attractors, which we call parametric attractors. We systematically study the mechanics, symmetry, dissipation, Lyapunov exponents and Poincaré maps of the hyperchaotic complex system. We extend the hyperchaotic complex system to fractional order, and discuss the influence of order and parameters’ change on fractional order new hyperchaotic system, and compare it with integer order. What is interesting is that there exist parametric attractors in both integer order and fractional order of the new system. Based on the integer order and fractional order, we further analyze the new hyperchaotic complex system of hybrid order, propose the definition of complex chaotic family and carry out mechanical analysis.
TRAVELING WAVE SOLUTION OF FRACTAL KdV-BURGERS–KURAMOTO EQUATION WITHIN LOCAL FRACTIONAL DIFFERENTIAL OPERATOR
Authors: SUN JIANSHE
Published: July 2021

In this work, space-time fractal model about nonlinear KdV-Burgers–Kuramoto (NKBK) equation which describes nonlinear physical phenomena and involves instability, dissipation, and dispersion parameters has been put forward through coupling fractional complex transform (FCT) via local fractional derivative (LFD) for the first time. These measures are considered in the sense of local derivative operators. Analytical approximate solutions of the model are obtained by local fractional reduced differential transform method (LFRDTM). The obtained results related to physical phenomenon in Cantorian time-space reveal that the suggested project is easy to use and the calculation is more precise. The graphical representation of special solution of LFNKBK yields interesting and better physical consequences of NKBK with LFD.
The structure of entrance laws for time-inhomogeneous Ornstein–Uhlenbeck processes with Lévy noise in Hilbert spaces
Authors: Majid Narges Rezvani , Röckner Michael
Published: July 2021

This paper is about the structure of all entrance laws (in the sense of Dynkin) for time-inhomogeneous Ornstein–Uhlenbeck processes with Lévy noise in Hilbert state spaces. We identify the extremal entrance laws with finite weak first moments through an explicit formula for their Fourier transforms, generalizing corresponding results by Dynkin for Wiener noise and nuclear state spaces. We then prove that an arbitrary entrance law with finite weak first moments can be uniquely represented as an integral over extremals. It is proved that this can be derived from Dynkin’s seminal work “Sufficient statistics and extreme points” in Ann. Probab. 1978, which contains a purely measure theoretic generalization of the classical analytic Krein–Milman and Choquet Theorems. As an application, we obtain an easy uniqueness proof for [Formula: see text]-periodic entrance laws in the general periodic case. A number of further applications to concrete cases are presented.
Stochastic version of Henry type Gronwall’s inequality
Authors: Mekki Slimane , Nieto Juan J. , Ouahab Abdelghani
Published: July 2021

We use Young’s and Hölder inequality combined with classical Gronwall’s inequality to derive present a new version of the stochastic of Gronwall’s inequalities with singular kernels.
Local well-posedness for the quantum Zakharov system in three and higher dimensions
Authors: Kato Isao
Published: July 2021

We study the Cauchy problem associated with a quantum Zakharov-type system in three and higher spatial dimensions.Taking the quantum parameter to unit and developing Fourier restriction norm arguments, we establish local well-posedness property for wider range than the one known for the Zakharov system.
Effect of Wing Flexibility on the Lift Force Generated by a 2D Model Insect Wing Flapping in Hover Mode
Authors: Wang Li , Wu Tzuyin
Published: July 2021

In this study, we numerically examine the effect of wing flexibility on the lift force generated by a modeled flapping wing that simulates an insect flight in hover mode. The flow field around the flapping wing is assumed to be two-dimensional (2D), and the flow equations are formulated with the notion of “immersed boundary” for easy handling of the moving-boundary problem. In the 2D framework, the wing chord is treated as an elastic filament. To account for the large deformation in the wing, the motion of the filament is modeled using a geometrically nonlinear equation for bending beams. Both sets of equations are then solved according to the fluid–structure interaction concept using appropriate numerical schemes. Time variation of lift force on the wing is calculated for different values of wing flexural rigidity. Effects of elastic deformation of the wing and interactions between the bending wing and vortical flow structure are discussed. Flexural rigidity that gives the highest average lift force on the wing is sought. This study affirms that the flexibility of wing and the vortex-pair capture phenomenon are crucial to the lift force generation in the flapping-wing mechanics.
Multiple Steady and Oscillatory Solutions in a Collapsible Channel Flow
Authors: Wang Danyang , Luo Xiaoyu , Stewart Peter S.
Published: July 2021

In this paper we study flow driven through a finite-length planar rigid channel by a fixed upstream flux, where a segment of one wall is replaced by a pre-stressed elastic beam subject to uniform external pressure. The steady and unsteady systems are solved using a finite element method. Previous studies have shown that the system can exhibit three steady states for some parameters (termed the upper, intermediate and lower steady branches, respectively). Of these, the upper and lower are stable to non-oscillatory perturbations, while the intermediate branch is always unstable. These upper and lower steady branches can (independently) become unstable to self-excited oscillations. We show that for some parameter combinations the system is unstable to both upper and lower branch oscillations simultaneously. However, we show that these two instabilities eventually merge together for large enough Reynolds numbers, exhibiting a nonlinear limit cycle which retains characteristics of both the upper and lower branches of oscillations. Furthermore, we show that increasing the beam pre-tension suppresses the region of multiple steady states but preserves the onset of oscillations. Conversely, increasing the beam thickness (a proxy for increasing bending stiffness) suppresses both multiple steady states and the onset of oscillations.
Highly Accurate Analytical Approximate Solutions to Mixed-Parity Duffing Equation
Authors: Sun W. P. , Miao K. L. , Yu Y. P. , Lim C. W.
Published: July 2021

In this paper, a highly accurate analytical approximation solution method to a class of mixed-parity Duffing equation is proposed. The system may be attributed to the free vibration of laminated anisotropic plates or the simplified problem of particle vibration. The system is first analyzed qualitatively and subsequently, the analytic approximate periodic solution within the parametric range is constructed. The first approximate solution with a suitable initial condition can be obtained by using the proposed method. Subsequently, higher precision approximate solutions are constructed by combining Newton’s method and harmonic balance method. These analytical solutions have excellent approximation accuracy as verified by numerical solutions derived from exact analytical expressions.
China–India Rivalry: The Saga of Game Changers
Authors: SURYANARAYANA P S
Published: July 2021

China and India have surprised the world by their military brinkmanship since mid-2020 amid the global coronavirus pandemic. Also surprising was their sudden disengagement at a key site, Pangong Tso Lake area in the western sector of their disputed boundary, in February 2021. But the continuing crisis has eroded their summit-level consensus reached in 2018 and 2019 that they were neighbourly partners, not rivals. The genesis of this crisis is the clash of their new perspectives on the Kashmir issue which, originally an India–Pakistan affair, has now become a major Chinese concern as well. Two new game changers in the troubled Sino–Indian engagement have caused this crisis. The author suggests a nuanced agreement on mutual military accommodation. Such an accord could create the ambience for serious negotiations to settle the intractable Sino–Indian boundary disputes.
Battling over Social Media: Public Protest and State Responses to Dr Li Wenliang’s Death in China
Authors: LAI Hongyi
Published: July 2021

This article discusses the state and public reactions on the internet to the death of Dr Li Wenliang, the whistle-blower who warned of the COVID-19 outbreak in China. Contrary to findings in existing literature, this study argues that the society–state interaction over the internet is far more dynamic and complex, and that autocratic states have the capability and resilience to manage and even control the internet. While the internet could help rally waves of public outpourings and protests, the state, in response, broadcast its tactical concessions to ease widespread public anger. However, the state has been able to portray its overall highly effective control of the epidemic, thereby claiming political credits and legitimacy for governance.
Back to Strategic Competition? Assessing Japan’s Emerging China Policy under the Suga Administration
Authors: MIAO Ji
Published: July 2021

While Japanese Prime Minister Suga Yoshihide pledged to loyally inherit Abe Shinzo’s foreign policy, his administration’s emerging policy has undergone a major shift in recent months. The new foreign policy has swayed from one that is relatively more independent and balanced to one that is more responsive to America’s competitive China policy, an intensive security agenda, tightened scrutiny of economic and technological cooperation with China, and open intervention in issues that China deems as domestic affairs. This article seeks to make an initial assessment of the nature, scope and prospects of the Suga administration’s China policy.
Australia and China: Souring Relations with Little Chance of a Reset on the Horizon
Authors: WALTON David
Published: July 2021

This article examines the bilateral relationship between Australia and China, which has become problematic since 2015. The causes for the downturn in relations are examined and two key reasons are offered: Australia is caught in the middle of power contestation between the United States and China; and Australia’s fear of its economic overdependence on China. This article deduces what a reset would look like and how this may eventuate.
Understanding, Discovering, and Mitigating Habitual Smartphone Use in Young Adults
Authors: Roffarello Alberto Monge , De Russis Luigi
Published: July 2021

People, especially young adults, often use their smartphones out of habit: They compulsively browse social networks, check emails, and play video-games with little or no awareness at all. While previous studies analyzed this phenomena
qualitatively
, e.g., by showing that users perceive it as meaningless and addictive, yet our understanding of how to discover smartphone habits and mitigate their disruptive effects is limited. Being able to automatically assess habitual smartphone use, in particular, might have different applications, e.g., to design better “digital wellbeing” solutions for mitigating meaningless habitual use.

To close this gap, we first define a data analytic methodology based on clustering and association rules mining to automatically discover complex smartphone habits from mobile usage data. We assess the methodology over more than 130,000 phone usage sessions collected from users aged between 16 and 33, and we show evidence that smartphone habits of young adults can be characterized by various types of links between contextual situations and usage sessions, which are highly diversified and differently perceived across users. We then apply the proposed methodology in Socialize, a digital wellbeing app that
(i)
monitors habitual smartphone behaviors in real time and
(ii)
uses proactive notifications and just-in-time reminders to encourage users to avoid any identified smartphone habits they consider as meaningless. An in-the-wild study with 20 users (ages 19–31) demonstrates that Socialize can assist young adults in better controlling their smartphone usage with a significant reduction of their unwanted smartphone habits.
High-Value Token-Blocking: Efficient Blocking Method for Record Linkage
Authors: O’hare Kevin , Jurek-Loughrey Anna , De Campos Cassio
Published: July 2021

Data integration is an important component of Big Data analytics. One of the key challenges in data integration is record linkage, that is, matching records that represent the same real-world entity. Because of computational costs, methods referred to as blocking are employed as a part of the record linkage pipeline in order to reduce the number of comparisons among records. In the past decade, a range of blocking techniques have been proposed. Real-world applications require approaches that can handle heterogeneous data sources and do not rely on labelled data. We propose high-value token-blocking (HVTB), a simple and efficient approach for blocking that is unsupervised and schema-agnostic, based on a crafted use of Term Frequency-Inverse Document Frequency. We compare HVTB with multiple methods and over a range of datasets, including a novel unstructured dataset composed of titles and abstracts of scientific papers. We thoroughly discuss results in terms of accuracy, use of computational resources, and different characteristics of datasets and records. The simplicity of HVTB yields fast computations and does not harm its accuracy when compared with existing approaches. It is shown to be significantly superior to other methods, suggesting that simpler methods for blocking should be considered before resorting to more sophisticated methods.
Socially Aware Navigation: A Non-linear Multi-objective Optimization Approach
Authors: Banisetty Santosh Balajee , Forer Scott , Yliniemi Logan , Nicolescu Monica , Feil-Seifer David
Published: July 2021

Mobile robots are increasingly populating homes, hospitals, shopping malls, factory floors, and other human environments. Human society has social norms that people mutually accept; obeying these norms is an essential signal that someone is participating socially with respect to the rest of the population. For robots to be socially compatible with humans, it is crucial for robots to obey these social norms. In prior work, we demonstrated a Socially-Aware Navigation (SAN) planner, based on Pareto Concavity Elimination Transformation (PaCcET), in a hallway scenario, optimizing two objectives so the robot does not invade the personal space of people. This article extends our PaCcET-based SAN planner to multiple scenarios with more than two objectives. We modified the Robot Operating System’s (ROS) navigation stack to include PaCcET in the local planning task. We show that our approach can accommodate multiple Human-Robot Interaction (HRI) scenarios. Using the proposed approach, we achieved successful HRI in multiple scenarios such as hallway interactions, an art gallery, waiting in a queue, and interacting with a group. We implemented our method on a simulated PR2 robot in a 2D simulator (Stage) and a pioneer-3DX mobile robot in the real-world to validate all the scenarios. A comprehensive set of experiments shows that our approach can handle multiple interaction scenarios on both holonomic and non-holonomic robots; hence, it can be a viable option for a Unified Socially-Aware Navigation (USAN).
Photo Sequences of Varying Emotion: Optimization with a Valence-Arousal Annotated Dataset
Authors: Mousas Christos , Krogmeier Claudia , Wang Zhiquan
Published: July 2021

Synthesizing photo products such as photo strips and slideshows using a database of images is a time-consuming and tedious process that requires significant manual work. To overcome this limitation, we developed a method that automatically synthesizes photo sequences based on several design parameters. Our method considers the valence and arousal ratings of images in conjunction with parameters related to both the visual consistency of the synthesized photo sequence and the progression of valence and arousal throughout the photo sequence. Our method encodes valence, arousal, and visual consistency parameters as cost terms into a total cost function while applying a Markov chain Monte Carlo optimization techniques called simulated annealing to synthesize the photo sequence based on user-defined target objectives in a few seconds. As our method was developed for the synthesis of photo sequences using the valence-arousal emotional model, a user study was conducted to evaluate the efficacy of the synthesized photo sequences in triggering valence-arousal ratings as expected. Our results indicate that the proposed method synthesizes photo sequences in which valence and arousal dimensions are perceived as expected by participants; however, valence may be more appropriately perceived than arousal.
Towards Designing Mobile Apps for Independent Travel
Authors: Khan Al Majed , Dunlop Dr Mark D. , Lennon Dr Marilyn , Dubiel Dr Mateusz
Published: July 2021

Performing daily independent activities can be a challenge for people with Down's Syndrome (DS). This article investigates how to better support these activities with smart devices based on three cycles of a collaborative participatory action research (PAR) process. The first cycle involved semi-structured interviews (
n = 4
) with parents and an online survey (
n = 39
) with people with DS and their parents to explore barriers and opportunities for independent activities. This cycle highlighted that travelling independently was a common challenge among discussed barriers to independent activities for young adults with DS, an issue that smart devices have the potential to overcome. The second cycle involved seven focus group discussions (
n = 20
) with parents (
n = 13
) and young adults with DS (
n = 7
) for gaining deeper insights into barriers to independent travel. We explored key barriers to independent travel and gathered design requirements for smartphone apps to overcome these barriers. In the third cycle, we designed a digital prototype based on participant recommendations and conducted seven focus group meetings (
n = 19
) with caregivers (
n = 12
) and individuals with DS (
n = 7
). This final cycle reviewed the proposed digital prototype and validated the key barriers found in the second cycle. Overall, our studies confirmed that mobile technology can support people with DS in performing daily life activities that increase social inclusion. The studies resulted in identified barriers and requirements along with co-designed solutions for independent travel apps.
Constrained Dual-Level Bandit for Personalized Impression Regulation in Online Ranking Systems
Authors: Li Zhao , Song Junshuai , Hu Zehong , Wang Zhen , Gao Jun
Published: July 2021

Impression regulation plays an important role in various online ranking systems,
e.g.
, e-commerce ranking systems always need to achieve local commercial demands on some pre-labeled target items like fresh item cultivation and fraudulent item counteracting while maximizing its global revenue. However, local impression regulation may cause “butterfly effects” on the global scale,
e.g.
, in e-commerce, the price preference fluctuation in initial conditions (overpriced or underpriced items) may create a significantly different outcome, thus affecting shopping experience and bringing economic losses to platforms. To prevent “butterfly effects”, some researchers define their regulation objectives with global constraints, by using contextual bandit at the page-level that requires all items on one page sharing the same regulation action, which fails to conduct impression regulation on individual items. To address this problem, in this article, we propose a personalized impression regulation method that can directly makes regulation decisions for each user-item pair. Specifically, we model the regulation problem as a
C
onstrained
D
ual-level
B
andit (CDB) problem, where the local regulation action and reward signals are at the item-level while the global effect constraint on the platform impression can be calculated at the page-level only. To handle the asynchronous signals, we first expand the page-level constraint to the item-level and then derive the policy updating as a second-order cone optimization problem. Our CDB approaches the optimal policy by iteratively solving the optimization problem. Experiments are performed on both offline and online datasets, and the results, theoretically and empirically, demonstrate CDB outperforms state-of-the-art algorithms.
A Robust Reputation-Based Group Ranking System and Its Resistance to Bribery
Authors: Saúde João , Ramos Guilherme , Boratto Ludovico , Caleiro Carlos
Published: July 2021

The spread of online reviews and opinions and its growing influence on people’s behavior and decisions boosted the interest to extract meaningful information from this data deluge. Hence, crowdsourced ratings of products and services gained a critical role in business and governments. Current state-of-the-art solutions rank the items with an average of the ratings expressed for an item, with a consequent lack of personalization for the users, and the exposure to attacks and spamming/spurious users. Using these ratings to group users with similar preferences might be useful to present users with items that reflect their preferences and overcome those vulnerabilities. In this article, we propose a new reputation-based ranking system, utilizing multipartite rating subnetworks, which clusters users by their similarities using three measures, two of them based on Kolmogorov complexity. We also study its resistance to bribery and how to design optimal bribing strategies. Our system is novel in that it reflects the diversity of preferences by (possibly) assigning distinct rankings to the same item, for different groups of users. We prove the convergence and efficiency of the system. By testing it on synthetic and real data, we see that it copes better with spamming/spurious users, being more robust to attacks than state-of-the-art approaches. Also, by clustering users, the effect of bribery in the proposed multipartite ranking system is dimmed, comparing to the bipartite case.
Multi-Cycle-Consistent Adversarial Networks for Edge Denoising of Computed Tomography Images
Authors: Xu Xiaowe , Zhang Jiawei , Liu Jinglan , Ding Yukun , Wang Tianchen , Qiu Hailong , Yuan Haiyun , Zhuang Jian , Xie Wen , Dong Yuhao , Jia Qianjun , Huang Meiping , Shi Yiyu
Published: July 2021

As one of the most commonly ordered imaging tests, the computed tomography (CT) scan comes with inevitable radiation exposure that increases cancer risk to patients. However, CT image quality is directly related to radiation dose, and thus it is desirable to obtain high-quality CT images with as little dose as possible. CT image denoising tries to obtain high-dose-like high-quality CT images (domain
Y
) from low dose low-quality CT images (domain
X
), which can be treated as an image-to-image translation task where the goal is to learn the transform between a source domain
X
(noisy images) and a target domain
Y
(clean images). Recently, the cycle-consistent adversarial denoising network (CCADN) has achieved state-of-the-art results by enforcing cycle-consistent loss without the need of paired training data, since the paired data is hard to collect due to patients’ interests and cardiac motion. However, out of concerns on patients’ privacy and data security, protocols typically require clinics to perform medical image processing tasks including CT image denoising locally (i.e., edge denoising). Therefore, the network models need to achieve high performance under various computation resource constraints including memory and performance. Our detailed analysis of CCADN raises a number of interesting questions that point to potential ways to further improve its performance using the same or even fewer computation resources. For example, if the noise is large leading to a significant difference between domain
X
and domain
Y
, can we bridge
X
and
Y
with a intermediate domain
Z
such that both the denoising process between
X
and
Z
and that between
Z
and
Y
are easier to learn? As such intermediate domains lead to multiple cycles, how do we best enforce cycle- consistency? Driven by these questions, we propose a multi-cycle-consistent adversarial network (MCCAN) that builds intermediate domains and enforces both local and global cycle-consistency for edge denoising of CT images. The global cycle-consistency couples all generators together to model the whole denoising process, whereas the local cycle-consistency imposes effective supervision on the process between adjacent domains. Experiments show that both local and global cycle-consistency are important for the success of MCCAN, which outperforms CCADN in terms of denoising quality with slightly less computation resource consumption.
Measuring the Network Vulnerability Based on Markov Criticality
Authors: Li Hui-Jia , Wang Lin , Bu Zhan , Cao Jie , Shi Yong
Published: July 2021

Vulnerability assessment—a critical issue for networks—attempts to foresee unexpected destructive events or hostile attacks in the whole system. In this article, we consider a new Markov global connectivity metric—Kemeny constant, and take its derivative called
Markov criticality
to identify critical links.
Markov criticality
allows us to find links that are most influential on the derivative of Kemeny constant. Thus, we can utilize it to identity a critical link (
i
,
j
) from node
i
to node
j
, such that removing it leads to a minimization of networks’ global connectivity, i.e., the Kemeny constant. Furthermore, we also define a novel vulnerability index to measure the average speed by which we can disconnect a specified ratio of links with network decomposition. Our method is of high efficiency, which can be easily employed to calculate the Markov criticality in real-life networks. Comprehensive experiments on several synthetic and real-life networks have demonstrated our method’s better performance by comparing it with state-of-the-art baseline approaches.