Data collection protocols for VANETs: a survey

We live in the era of Intelligent Transport Systems (ITS), which is an extension of Vehicular AdHoc Networks (VANETs). In VANETs, vehicles act as nodes connected with each other and sometimes with a public station. Vehicles continuously exchange and collect information to provide innovative transportation services; for example, traffic management, navigation, autonomous driving, and the generation of alerts. However, VANETs are extremely challenging for data collection, due to their high mobility and dynamic network topologies that cause frequent link disruptions and make path discovery difficult. In this survey, various state-of-the-art data collection protocols for VANETs are discussed, based on three broad categories, i.e., delay-tolerant, best-effort, and real-time protocols. A taxonomy is designed for data collection protocols for VANETs that is essential to add precision and ease of understandability. A detailed comparative analysis among various data collection protocols is provided to highlight their functionalities and features. Protocols are evaluated based on three parametric phases. First, protocols investigation based on six necessary parameters, including delivery and drop ratio, efficiency, and recovery strategy. Second, a 4-D functional framework is designed to fit most data collection protocols for quick classification and mobility model identification, thus eradicating the need to read extensive literature. In the last, in-depth categorical mapping is performed to deep dive for better and targeted interpretation. In addition, some open research challenges for ITS and VANETs are discussed to highlight research gaps. Our work can thus be employed as a quick guide for researchers to identify the technical relevance of data collection protocols of VANETs.

Group Mobility Model for Complex Multimission Cooperation of UAV Swarm

In the unmanned aerial vehicle (UAV) swarm combat system, multiple UAVs’ collaborative operations can solve the bottleneck of the limited capability of a single UAV when they carry out complicated missions in complex combat scenarios. As one of the critical technologies of UAV collaborative operation, the mobility model is the basic infrastructure that plays an important role for UAV networking, routing, and task scheduling, especially in high dynamic and real-time scenarios. Focused on real-time guarantee and complex mission cooperative execution, a multilevel reference node mobility model based on the reference node strategy, namely, the ML-RNGM model, is proposed. In this model, the task decomposition and task correlation of UAV cluster execution are realized by using the multilayer task scheduling model. Based on the gravity model of spatial interaction and the correlation between tasks, the reference node selection algorithm is proposed to select the appropriate reference node in the process of node movement. This model can improve the real-time performance of individual tasks and the overall mission group carried out by UAVs. Meanwhile, this model can enhance the connectivity between UAVs when they are performing the same mission group. Finally, OMNeT++ is used to simulate the ML-RNGM model with three experiments, including the different number of nodes and clusters. Within the three experiments, the ML-RNGM model is compared with the random class mobility model, the reference class mobility model, and the associated class mobility model for the network connectivity rate, the average end-to-end delay, and the overhead caused by algorithms. The experimental results show that the ML-RNGM model achieves an obvious improvement in network connectivity and real-time performance for missions and tasks.

Development of Modify Random Waypoint Mobility Model of Routing Protocol for the Mobile Ad-Hoc Network

Mobility models are used to evaluated the network protocols of the ad hoc network using the simulation. The random waypoint model is a model for mobility which is usually used for performance evaluation of ad-hoc mobile network. Mobile nodes have the dynamic mobility in the ad hoc network so the mobility model plays an important role to evaluate the protocol performance.In this article, we developed modify random waypoint mobility (MRWM) model based on random waypoint for the mobile ad hoc network. In this article, the comparative analysis of modifying random waypoint mobility and random waypoint model on the ad hoc On-Demand Distance Vector (AODV) routing protocol has been done for large wireless ad hoc network (100 nodes) with the random mobile environment for the 1800s simulation time. To enhance the confidence on the protocol widespread simulations were accomplished under heavy traffic (i.e. 80 nodes) condition. The proposed model protocol has been investigated with the performance metrics: throughput; packet delivery ratio; packet dropping ratio; the end to end delay and normalized routing overhead. The obtained results revealed that proposed modify random waypoint mobility model reduces the mobility as compared to the random waypoint mobility model and it is trace is more realist.

Escape Path Obstacle-Based Mobility Model (EPOM) for Campus Delay-Tolerant Network

In Delay-Tolerant Networks (DTNs), humans are the main carriers of mobile devices, signifying that human mobility can be exploited by extracting nodes’ interests, social behavior, and spatiotemporal features for the performance evaluation of DTNs protocols. This paper presents a new mobility model that describes students’ daily activities in a campus environment. Unlike the conventional random walk models, which use a free space environment, our model includes a collision-avoidance technique that generates an escape path upon encountering obstacles of different shapes and sizes that obstruct pedestrian movement. We evaluate the model’s usefulness by comparing the distributions of its synthetic traces with realistic traces in terms of spatial, temporal, and connectivity features of human mobility. Similarly, we analyze the concept of dynamic movement clusters observed on the location-based trajectories of the studied real traces. The model synthetically generates traces with the distribution of the intercluster travel distance, intracluster travel distance, direction of movement, contact duration, intercontact time, and pause time similar to the distribution of real traces.

CORREDORES URBANOS COMO CONECTORES DE VIDA PÚBLICA. DIAGNÓSTICO DE LOS CORREDORES URBANOS CENTRALES EN LA AVENIDA 24 DE MAYO, AZOGUES

El cambio de modelo urbano asumido durante el siglo XX, trajo un sinnúmero de problemas como la priorización del vehículo, por lo que en la última década han surgido esfuerzos para dotar de importancia al ciudadano de a pie, en el espacio público. Esta investigación estudió las condiciones físico-espaciales de un corredor urbano donde el modelo centrado en el vehículo se acentúa, con la fnalidad de generar posibles estrategias que reviertan esta situación. Se tomó como caso de estudio a la Av. 24 de Mayo, en Azogues, y se lo analizó mediante una metodología mixta, que evaluó, detalladamente, tres zonas de estudio, determinando que la falta de accesibilidad y conectividad y el modelo de movilidad defendido por la ciudadanía, en general, infuyen directamente en las condiciones del espacio público peatonal y por ende en la habitabilidad urbana, perjudicando los desplazamientos a pie. Palabras clave: Espacio público; habitabilidad urbana; conectividad; accesibilidad; percepción. AbstractThe change of urban model assumed during the 20th century, brought countless problems such as the prioritization of vehicles, so in the last decade eforts have emerged to give importance to the citizen on foot in the public space. This original research studied the relationship of urban habitability with the physical-spatial conditions of an urban corridor, where the vehicle-centered model is accentuated, to generate possible strategies to reverse this situation. The Av. 24 de Mayo in Azogues was taken as a case study and analyzed using a mixed methodology that evaluated in detail three study areas, determining that the lack of accessibility and connectivity and the mobility model defended by citizens in general have a direct infuence on the conditions of the pedestrianpublic space and, therefore, on urban habitability, which afects walking Keywords: Public space; urban habitability; connectivity; accessibility; perception.

Professional Mobility as a Model for Overcoming Maladaptive Forms of a Person’s Psychological Defence in Conditions of Professional Development Crises

The article deals with the results of the analysis of the person’s professional mobility as a comprehensive tool for overcoming the professional crises. It also determines the existence of many unascertained psychological problems in its structure. One of these problems is the problem of overcoming maladaptive forms of a person’s psychological defence based on his professional mobility in stressful conditions of the professional development crises. Stressful uncertainty in the professional crisis and the high ambivalent tension, which the person is experiencing, characterize the specialist’s maladaptive development according to the “catastrophic” scenario. In the conditions of the professional development crisis a specialist cannot leave it adaptively and flexibly due to a limited number of rigidly patterned professional barriers and behaviour models. Such maladaptive patterned movement of a specialist towards the disintegrational destruction of the whole system of his professional development can be overcome constructively on the basis of his professional mobility model, selection and realization of the further professional movement vector. We consider the interactive strategy of a specialist’s behaviour for constructive overcoming professional crises in the system of his professional development, based on the development of the ability of directed transitions to new professional movement trajectories in the points of the system bifurcation, as the professional mobility.

A Typical Analysis of Flying Ad-Hoc Network Applications in Agriculture and Irrigation System

With the speedy technological enhancement and decrementin man power, technologies are being involved in everyphase of our life and their proper application leads to ahealthy life indeed. Agriculture and irrigation are sources ofman’s potential. Different sensors and electronicsequipment are deployed to commercialize in market andmaintaining the cost effectiveness in several domains. Forthe sake of cost effectiveness and the betterment ofagricultural professionals, UAVs (unmanned aerialvehicles) can be deployed for surveillance, utilization ofpesticides and insecticides and detection of bioprocessingerrors. Single mode and multi-mode UAV system both aresuitable for application of FANET. With the propercollaboration and coordination of the clusters of UAVsforming a network, linked with a ground infrastructure,GCS or satellite will exceed the competences of singleUAV system. However, one of the vital design issuesFANETs deal with is in selecting the accurate routingprotocol which is prerequisite for the creation of FANET. Inthis paper we will discuss about the routing protocols ofFANET in different platforms and different strategicmanners. The open research challenges will be discussedand possible solutions will be attempted to be drawn fromconclusion. The main contribution lies in the suggesting themost suitable routing protocol for each particular agricultureapplication based on the mobility model and requirement.

Simulation of double-leg stance in conditions of limited hip mobility

Hip osteoarthritis is one of the most common and disabling conditions affecting the elderly. Coxarthrosis is accompanied by impairment of the amortization properties of cartilage, its thinning and destruction, the appearance of pain syndrome, impaired motor functions due to a decrease in muscle strength and the development of stable flexion-adduction contractures, which change congenital motor programs, and, with a prolonged course of degenerative disease, lead to the formation of pathological habits. Objective: to determine the required strength of the muscles of the lower limb in conditions of limited hip mobility to support an upright posture in double-leg stance. Materials and methods. The work of the muscles of the lower extremities under conditions of restricted hip mobility was simulated using the OpenSim 4.0 software. It is based on the ToyLandingModel, which has contact geometry objects to fix the model on the support area. Four models were created: norm (without limitation of joint mobility), model 2 — adduction of 5°, model 3 — adduction of 7°, flexion of 10°, model 4 — adduction of 10°, flexion of 20°, shortening of the femur bones by 2 cm. Results. It was found that with insignificant adduction contractures of the hip joint, the work of the muscles of the lower limb changes slightly during double-leg stance. With flexion-adduction contractures, changes are observed in almost all muscles of the lower limb. There are some peculiarities in the work of muscles under contractures. All the muscles around the thigh reduce the strength necessary to maintain balance, while the lower leg muscles, on the contrary, increase the required strength several times. For example, m.medial gastrocnemius with flexion-adduction contracture and limb shortening develops10 times higher compensatory force (200 N) than in normal conditions (20 N), and although muscle resources are 1500 N, it is very demanding to maintain an upright posture. Similarly, m.tibialis posterior require an increase in strength (threefold), but the antagonist muscle m.tibialis anterior, on the contrary, reduces the force of contraction by an average of 100 N. Conclusions. According to the data of the conducted modeling of double-leg stance with limited hip mobility, it was proved that an increase in limited movements changes the nature of muscle contraction of the entire lower limb and pelvis. The analysis of the obtained results showed that restriction of movements reduces the required force of muscle stabilization around the hip joint, and increases the required force of contraction of the leg muscles. That is, there is an imbalance in the muscles.

Gyre Precoding and T-Transformation-Based GFDM System for UAV-Aided mMTC Network

In this paper, an unmanned aerial vehicle (UAV)-aided multi-antenna configured downlink mmWave cooperative generalized frequency division multiplexing (GFDM) system is proposed. To provide physical layer security (PLS), a 3D controlled Lorenz mapping system is introduced. Furthermore, the combination of T-transformation spreading codes, walsh Hadamard transform, and discrete Fourier transform (DFT) techniques are integrated with a novel linear multi-user multiple-input multiple-output (MU-MIMO) gyre precoding (GP) for multi-user interference reduction. Furthermore, concatenated channel-coding with multi-user beamforming weighting-aided maximum-likelihood and zero forcing (ZF) signal detection schemes for an improved bit error rate (BER) are also used. The system is then simulated with a single base station (BS), eight massive machine-type communications (mMTC) users, and two UAV relay stations (RSs). Numerical results reveal the robustness of the proposed system in terms of PLS and an achievable ergodic rate with signal-to-interference-plus-noise ratio (SINR) under the implementation of T-transformation scheme. By incorporating the 3D mobility model, brownian perturbations of the UAVs are also analyzed. An out-of-band (OOB) reduction of 320 dB with an improved BER of 1×10−4 in 16-QAM for a signal-to-noise ratio, Eb/N0, of 20 dB is achieved.