Privacy-Preserving Federated Mobility Prediction with Compound Data and Model Perturbation Mechanism

Human mobility prediction is important for many applications.However,training an accurate mobility prediction model requires a large scale of human trajectories,where privacy issues become an important problem.The rising federated learning provides us with a promising solution to this problem,which enables mobile devices to collaboratively learn a shared prediction model while keeping all the training data on the device,decoupling the ability to do machine learning from the need to store the data in the cloud.However,existing federated learningbased methods either do not provide privacy guarantees or have vulnerability in terms of privacy leakage.In this paper,we combine the techniques of data perturbation and model perturbation mechanisms and propose a privacy-preserving mobility prediction algorithm,where we add noise to the transmitted model and the raw data collaboratively to protect user privacy and keep the mobility prediction performance.Extensive experimental results show that our proposed method significantly outperforms the existing stateof-the-art mobility prediction method in terms of defensive performance against practical attacks while having comparable mobility prediction performance,demonstrating its effectiveness.

LiMo 2040 Sustainable urban Living and Mobility Concept-Elevator System

How can individual mobility in urban areas be maintained alongside scooters and cargo bikes if conventional vehicles are foreseeably no longer allowed to enter city centers?And how can urban living be combined with individual mobility in a sustainable and socially acceptable way?LiMo-2040 attempts to provide answers to these questions.It follows a holistic approach according to the criteria:As light,as compact and as simple(cost-effective)as possible.Modular e-vehicle concepts(consisting of vehicle cabin and chassis)are known,but have not yet been thought through to their logical conclusion.The LiMo cabin is not only a vehicle cabin,but also a component of a modern high-rise apartment.It therefore requires no parking space and combines urban living and individual mobility sustainably and cost-effectively.If a vehicle is needed,an app can be used to book a chassis that comes along autonomously and waits until the cabin,including its occupants,travels down a sophisticated rail system,docks and autonomously heads for the desired destination.

5G High Mobility Wireless Communications: Challenges and Solutions

The fifth generation(5G) network is expected to support significantly large amount of mobile data traffic and huge number of wireless connections,to achieve better spectrum- and energy-efficiency,as well as quality of service(QoS) in terms of delay,reliability and security.Furthermore,the 5G network shall also incorporate high mobility requirements as an integral part,providing satisfactory service to users travelling at a speed up to 500 km/h.This paper provides a survey of potential high mobility wireless communication(HMWC) techniques for 5G network.After discussing the typical requirements and challenges of HMWC,key techniques to cope with the challenges are reviewed,including transmission techniques under the fast timevarying channels,network architecture with mobility support,and mobility management.Finally,future research directions on 5G high mobility communications are given.

Position-assisted fast handover schemes for LTE-advanced network under high mobility scenarios

Two position-assisted fast handover schemes, scheme A and scheme B, for LTE-A system under very high mobility scenarios, are proposed, together with their performance evaluation. Scheme A is designed to reduce handover delay by making handover preparation before handover starts. Scheme B aims at reducing unnecessary handovers and improving handover success rate, by calculating the geographically best target handover cell, which makes it easier for mobile terminals to access the target cell. A system level simulation is conducted to evaluate the performance of these two schemes. It is shown that, scheme A could reduce inter-site handover delay by about 50 ms, while scheme B could cut down nearly 50% of all handovers when time-to-trigger （TTT） is 0 ms. Besides, as TTT gets larger, Scheme B has much better success rate.

The Influence of Public Policies on Urban Mobility： A Comparative Study between Porto Alegre （Brazil） and Washington D.C. （United States）

Increasing urbanization rates observed in the last decades have significantly contributed to a higher number of travelers to urban environments. The objective of this study was to identify measures and factors that encourage the use of alternative transportation in the cities of Washington D.C., USA and Porto Alegre, Brazil. The methodology used to compare these two cities was an evaluation of their urban mobility plans, including strategic analyses and measures to promote the use of public transport. This approach was based on factors described in the following document： ＂Urban Sustainability： Impacts of Economic Development and Their Consequences on the Process of Urbanization in Emerging Countries＂, prepared by the United Nations. The results indicate different planning strategies, ranging from focusing on tax integration policies in order to become more financially attractive to the user, to using different modes of mass transportation integrated with active mobility. In Washington D.C., an innovative strategy was developed in preparation to forecast scenarios, as the measures comprised projection for the year 2040, which will respond to mobility demands in the coming decades.

Mobility-driven user-centric AP clustering in mobile edge computing-based ultra-dense networks

ultra-Dense Network(UDN)has been envisioned as a promising technology to provide high-quality wireless connectivity in dense urban areas,in which the density of Access Points(APs)is increased up to the point where it is comparable with or surpasses the density of active mobile users.In order to mitigate inter-AP interference and improve spectrum efficiency,APs in UDNs are usually clustered into multiple groups to serve different mobile users,respectively.However,as the number of APs increases,the computational capability within an AP group has become the bottleneck of AP clustering.In this paper,we first propose a novel UDN architecture based on Mobile Edge Computing(MEC),in which each MEC server is associated with a user-centric AP cluster to act as a mobile agent.In addition,in the context of MEC-based UDN,we leverage mobility prediction techniques to achieve a dynamic AP clustering scheme,in which the cluster structure can automatically adapt to the dynamic distribution of user traffic in a specific area.Simulation results show that the proposed scheme can highly increase the average user throughput compared with the baseline algorithm using max-SINR user association and equal bandwidth allocation,while it guarantees at the same time low transmission delay.

Rapid authentication of sesame oil using ion mobility spectrometry and chemometrics

To ensure authenticity of sesame oil,an authentication technology was proposed using ion mobility spectrometry(IMS)and chemometrics.One-class classification(OCC)methods including one-class partial least squares(OCPLS)and one-class support vector machine(OCSVM)were employed to build authentication models for sesame oil.Subsequently,an independent test set was used to validate the constructed models.Validation set of 45 adulterated oils indicated that prediction correction rate of OCPLS model reached 95.6%(43 out of 45).Moreover,the complete set of sesame oils adulterated by sesame oil essence could be identified as counterfeit.Compared with previous studies,OCPLS model could work to identify untargeted adulteration.In conclusion,OCC method could effectively detect adulterated sesame oils containing as little as 10%other vegetable oils.This study provided a rapid screening method for adulterated sesame oil in market surveillance and a reference for developing authentication methods of other edible oils.

Pedestrians Mobility on Public Sidewalks Evaluated by the IAAPE Method

This research aims to evaluate walkability as a strategy of urban mobility in relation to physical characteristics of accessibility and attractiveness from public sidewalks characteristics in the city of Passo Fundo/RS-Brazil using the IAAPE （indicators of attraction and pedestrian accessibility） method. The concept of walkability corresponds to the simple act of walking in a pleasant way along the footpaths. Therefore, the IAAPE method was used, which considers aspects of connectivity, comfort, conviviality, coexistence, convenience, clarity and commitment in relation to the space evaluated. In this study, 40 adults, elderly, pregnant and wheelchair subjects were interviewed for evaluating the importance criteria on public sidewalks for a given type of user. In general, reduced sidewalk dimensions and obstacle presence are the main displacement hurdles in most of the cases analyzed. Thus, improvements are needed to avoid stress situations that arise from daily routine, to encourage physical activities, accessibility, and the emergence of meeting and leisure points.

A Mobility Management Solution Based on ID/Locator Separation

Current mobility management solutions based on ID/Locator separation are not easily deployed and cannot solve routing scalability and mobility problems. This paper proposes a novel network architecture based on ID/Locator separation and suggests a new mobility management solution. This solution solves the problem of scalability in the network and also provides better support for mobility. It can be easily deployed because no modification of the mobile host’s protocol stack is required. The identifier contains some routing information; so the solution provides intrinsic interworking with traditional mobile hosts. Because the mapping systems are distributed to the edge networks, robustness of the whole system is enhanced and handover delay is decreased.

Dynamic selection scheme for cooperative relay under high mobility environment

The mobility of relay has great influence on the performance of a cooperative relay system.This paper proposes a dynamic selection scheme under the amplify-and-forward communication mode in high mobility environment,based on the estimation of channels and the power allocation for each relay node by comparing it with the pre-set threshold.This scheme is used to choose the cooperative relay dynamically for a multiple relay scenario.Simulation results show that this proposed relay selection scheme decreases the outage probability effectively,maintains system capacity well,and improves the performance of the relay system.

Road traffic nanoparticle characteristics:Sustainable environment and mobility

Human effects and environment impacts associated with nanoparticles generated from road traffic have recently attracted wide attention.Knowledge of the influencing variables on both number and mass of nanoparticles,sources,characteristics and limitations of advanced commercially accessible instruments for monitoring nanoparticles,are still scarce and not sufficient to make regulatory decision on solid particles smaller than 23 nm(SPN<23 nm).Given the harmful effects of nanoparticles on human health(i.e.visibility impairment,cardiac-rhythm disturbance,heart attacks,premature death,etc.),their control and assessment seem to be an absolute priority.In this overview,we classify and analyze the existing knowledge of nanoparticles in road traffic atmosphere,recent progress,and emerging priorities in research related to these topics.The major aspects of ongoing research in this field,and a brief discussion of the main sources of atmosphere nanoparticles are presented.The subsequent section focuses on the influencing parameters of nanoparticles including climate conditions,height above the road surface and distance between source(road traffic)and sampling site.The next section provides a comprehensive summary on sampling measurement methodologies and instrumental techniques.We also review the health and environment implications associated with particle exposure.Finally,an evaluation of the state of research related to nanoparticles together with highlights for future research activities are also presented.

Performance of LDPC Coded OTFS Systems over High Mobility Channels

The upcoming 6G wireless networks have to provide reliable communications in high-mobility scenarios at high carrier frequencies.However,high-mobility or high carrier frequencies will bring severe inter-carrier interference(ICI)to conventional orthogonal fre⁃quency-division multiplexing(OFDM)modulation.Orthogonal time frequency space(OTFS)modulation is a recently developing multi-carrier transmission scheme for wireless commu⁃nications in high-mobility environments.This paper evaluates the performance of coded OT⁃FS systems.In particular,we consider 5G low density parity check(LDPC)codes for OTFS systems based on 5G OFDM frame structures over high mobility channels.We show the per⁃formance of the OTFS systems with 5G LDPC codes when sum-product detection algorithm and iterative detection and decoding are employed.We also illustrate the effect of channel estimation error on the performance of the LDPC coded OTFS systems.

Urban Mobility： Method of Analysis of the Adequacy of Public Policies in Cities Based on the Principles Proposed by the UN

Addressing urban mobility is a priority for government agencies due to increasing problems of travel and lack of accessibility, generated by increasing rates of population growth and motorization. The general objective of this study is to propose a method of analysis of the adequacy of policies, aimed at sustainable mobility and its impacts on urbanism. Methodologically, the analysis is based on the parameters proposed by the UN （United Nations）, namely, sectorial planning, mobility funding, management efficiency of urban mobility systems; and mobility system and support for green technology. The object of study is the public policies expressed in urban mobility plans, master plans and regional development plans. Through the applicability of this method, the results show the possibility of verifying the adequacy of public policies as a mechanism that induces improvements in urban mobility with greater levels of sustainability and the possibility of universalized access to users.

Urban air mobility(UAM)and ground transportation integration:A survey

This study explores urban air mobility(UAM)as a strategy for mitigating escalating traffic congestion in major urban areas as a consequence of a static transportation supply versus dynamic demand growth.It offers an indepth overview of UAM development,highlighting its present state and the challenges of integration with established urban transport systems.Key areas of focus include the technological advancements and obstacles in electric vertical take-off and landing(eVTOL)aircrafts,which are essential for UAM operation in urban environments.Furthermore,it explores the infrastructure requirements for UAM,including vertiport deployment and the creation of adept air traffic control(ATC)systems.These developments must be integrated into the urban landscape without exacerbating land-use challenges.This paper also examines the regulatory framework for UAM,including existing aviation regulations and the necessity for novel policies specifically designed for urban aerial transport.This study presents a comprehensive perspective for various stakeholders,from policymakers to urban planners,highlighting the need for a thorough understanding of UAM’s potential and effective assimilation into urban mobility frameworks.

A novel approach to model the role of mobility suppression and vaccinations in containing epidemics in a network of cities

This paper presents a comprehensive agent-based model for the spread of an infection in a network of cities.Directional mobility is defined between each two cities and can take different values.The work examines the role that such mobility levels play in containing the infection with various vaccination coverage and age distributions.The results indicate that mobility reduction is sufficient to control the disease under all circumstances and full lockdowns are not a necessity.It has to be reduced to different ratios depending on the vaccination level and age distribution.A key finding is that increasing vaccination coverage above a certain level does not affect the mobility suppression level required to control the infection anymore for the cases of young population and heterogeneous age distributions.By investigating several migration and commuting patterns,it is found that shutting mobility in a few local places is favored against reducing mobility over the entire country network.In addition,commuting-and not migration-influences the spread level of the infection.The work offers an exclusive combined network-based and agent-based model that makes use of randomly generated mobility matrices.

Mobility driven network slicing: an enabler of on demand mobility management for 5G

As different requirements on mobility support will be introduced by diversified communication scenarios in the fifth generation （5G）, on demand mobility management is put forward to simplify signaling process, reduce terminal power consumption, improve network efficiency and so on. In order to enable on demand mobility management in 5G networks, a mobility driven network slicing （MDNS） was proposed, which takes individual mobility support requirements into account while customizing networks for different mobile services. Within the MDNS framework, the actual levels of required mobility support are determined by a mobility description system, and network slice templates with the corresponding mobility management schemes are defined by a network slice description function. By instantiating the network slices, each mobile terminal could be directed to the network slice with the most appropriate mobility management scheme. Based on this, a prototype was implemented to validate the feasibility of MDNS framework, i.e. creating multiple network slices with different mobility management schemes. In addition, the performance evaluation on average cost of processing a mobility event is conducted for the proposed MDNS framework and the long term evolution （LTE） system, and operating benefits are analyzed including efficiency and scalability.

Modelling the effect of non-pharmaceutical interventions on COVID-19 transmission from mobility maps

The world has faced the COVID-19 pandemic for over two years now,and it is time to revisit the lessons learned from lockdown measures for theoretical and practical epidemiological improvements.The interlink between these measures and the resulting change in mobility(a predictor of the disease transmission contact rate)is uncertain.We thus propose a new method for assessing the efficacy of various non-pharmaceutical interventions(NPI)and examine the aptness of incorporating mobility data for epidemiological modelling.Facebook mobility maps for the United Arab Emirates are used as input datasets from the first infection in the country to mid-Oct 2020.Dataset was limited to the pre-vaccination period as this paper focuses on assessing the different NPIs at an early epidemic stage when no vaccines are available and NPIs are the only way to reduce the reproduction number(R_(0)).We developed a travel network density parameterβ_(t)to provide an estimate of NPI impact on mobility patterns.Given the infection-fatality ratio and time lag(onset-to-death),a Bayesian probabilistic model is adapted to calculate the change in epidemic development withβt.Results showed that the change inβ_(t)clearly impacted R_(0).The three lockdowns strongly affected the growth of transmission rate and collectively reduced R_(0)by 78%before the restrictions were eased.The model forecasted daily infections and deaths by 2%and 3%fractional errors.It also projected what-if scenarios for different implementation protocols of each NPI.The developed model can be applied to identify the most efficient NPIs for confronting new COVID-19 waves and the spread of variants,as well as for future pandemics.

Interpretable Machine Learning Method for Compressive Strength Prediction and Analysis of Pure Fly Ash-based Geopolymer Concrete

In order to study the characteristics of pure fly ash-based geopolymer concrete(PFGC)conveniently,we used a machine learning method that can quantify the perception of characteristics to predict its compressive strength.In this study,505 groups of data were collected,and a new database of compressive strength of PFGC was constructed.In order to establish an accurate prediction model of compressive strength,five different types of machine learning networks were used for comparative analysis.The five machine learning models all showed good compressive strength prediction performance on PFGC.Among them,R2,MSE,RMSE and MAE of decision tree model(DT)are 0.99,1.58,1.25,and 0.25,respectively.While R2,MSE,RMSE and MAE of random forest model(RF)are 0.97,5.17,2.27 and 1.38,respectively.The two models have high prediction accuracy and outstanding generalization ability.In order to enhance the interpretability of model decision-making,we used importance ranking to obtain the perception of machine learning model to 13 variables.These 13 variables include chemical composition of fly ash(SiO_(2)/Al_(2)O_(3),Si/Al),the ratio of alkaline liquid to the binder,curing temperature,curing durations inside oven,fly ash dosage,fine aggregate dosage,coarse aggregate dosage,extra water dosage and sodium hydroxide dosage.Curing temperature,specimen ages and curing durations inside oven have the greatest influence on the prediction results,indicating that curing conditions have more prominent influence on the compressive strength of PFGC than ordinary Portland cement concrete.The importance of curing conditions of PFGC even exceeds that of the concrete mix proportion,due to the low reactivity of pure fly ash.

Exploring link generation in a temporal evolution network for human mobility

The prevalence of mobile devices has spurred human mobility to be applied in mobile networking and communications by using network science, in which the temporal evolution of a network topology is of great importance for protocol design and performance analysis. This paper focuses on link generation in a temporal evolution network. Based on observations revealing the strong correlation between the connection patterns of different time periods, a link generation potential based on historical connections is proposed in this paper, aiming to provide a method for making topological predictions with less randomness. Using MIT Reality dataset, an evaluation of the accuracy of the proposed method was conducted. The experimental results demonstrate the proposal's adequacy in terms of its accuracy.

Advances in broadband wireless communications under high-mobility scenarios

未来活动通讯系统瞄准提供很高的数据传播率，甚至在象高速度的车轮轨道火车，磁悬浮火车火车，高速公路车辆，飞机，指导导弹或太空船那样的高活动性的情形。一个特别地重要的商业应用程序是对高速度的宽带的强壮、增加的世界范围的要求无线通讯(多达 574.8 ? km/h 测试速度或 380 ? km/h 广告速度)为象为旅客的机载的娱乐服务那样的应用程序在铁路，提供的数据，声音和录像满足，火车控制，训练派遣，火车传感器地位处理和监视。在如此的高活动性的情形，有很多通讯挑战，包括快移交，更新的地点，当模特儿的高速度的隧道，评价和均等， anti-Doppler 传播技术，快力量控制，和奉献网络建筑学。因为在很高速度的情形的信号传播将不可避免地经历 s ……