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In recent research developments, the application of mobile agents (MAs) has attracted extensive research in wireless sensor networks (WSNs) due to the unique benefits it offers, such as energy conservation, network bandwidth saving, and flexibility of open usage for various WSN applications. The majority of the proposed research ideas on dynamic itinerary planning agent-based algorithms are efficient when dealing with node failure as a result of energy depletion. However, they generate inefficient groups for MAs itineraries, which introduces a delay in broadcasting data return back to the sink node, and they do not consider the expanding size of the MAs during moving towards a sequence of related nodes. In order to rectify these research issues, we propose a new Graph-based Dynamic Multi-Mobile Agent Itinerary Planning approach (GDMIP). GDMIP works with "Directed Acyclic Graph" (DAG) techniques and distributes sensor nodes into various and efficient group-based shortest-identified routes, which cover all nodes in the network using intuitionistic fuzzy sets. MAs are restricted from moving in the predefined path and routes and are responsible for collecting data from the assigned groups. The experimental results of our proposed work show the effectiveness and expediency compared to the published approaches. Therefore, our proposed algorithm is more energy efficient and effective for task delay (time). [ABSTRACT FROM AUTHOR]

To assist cruise companies in designing the technic-economic specifications of "fly-cruise" products and attracting international tourists, this paper proposes a model of itinerary planning and dynamic pricing with advanced algorithm. We integrate the Reinforcement Learning (RL) and Genetic Algorithm (GA) to develop a hybrid algorithm to obtain the optimal solution of the model. Taking Malaysian consumers travelling to China for cruise tours as a case study, we empirically test the model with real market data and use it to analyze the impact of innovating "fly-cruise" products on the deficit of China's inbound and outbound tourists. The results show that the innovating "fly-cruise" products will attract 20.52 million Southeast Asian tourists to China annually and generate a profit of US$ 3.56 billion for cruise companies. It highlights that the advanced algorithm based "fly-cruise" products can help China to effectively reduce the deficit of inbound and outbound tourists and improve the international balance of service trade. [ABSTRACT FROM AUTHOR]

A cooperative truck platoon is a set of virtually linked trucks driving with a small intra-vehicle headway enabled by connected and automated vehicle technologies. One of the primary benefits of truck platooning is energy savings due to the reduction of aerodynamic drag on the platooned vehicles. The focus of this paper is on scheduling travel itineraries of a given set of trucks to facilitate the formation of platoons to maximize energy savings. By constructing a time-expanded network, we formulate the problem as a minimum concave-cost network flow problem, and devise a few solution methods to find the optimal or high-quality solutions. The solution methods include an outer approximation algorithm for solving a mixed-integer convex minimization reformulation of the problem, a dynamic-programming-based heuristic scalable to large-scale instances, and a fast approximation algorithm with guaranteed performance for a restrictive version of the problem. All the proposed algorithms are examined and benchmarked on medium to large networks under various test scenarios. The numerical results demonstrate the efficiency of the proposed methods and their applicability in real-world settings. • Formulate truck platooning planning as a minimum concave-cost network flow problem. • Develop a hybrid outer approximation/local search algorithm for medium-sized problems. • Propose a dynamic-programming-based heuristic for large-scale problems. • Devise an approximation algorithm for a special-case truck platooning problem. [ABSTRACT FROM AUTHOR]

Mobile Agent (MA) technology brings many benefits into Wireless Sensor Networks (WSNs), such as saving network bandwidth and enabling energy efficient mechanisms for collecting sensor data. Nowadays, itinerary planning for MAs is one of the most important features of the WSN. However, the way in which all dispatched MAs are routed inside the sensor networks must be intelligently planned to reduce energy consumption and improve information accuracy. There have been many research efforts designing itinerary planning algorithms to deploy multiple MAs in a given sensor network, where routes are generated so that MAs can follow different routes to collect data from sensor nodes efficiently and effectively. This paper proposes a new energy efficient Graph-based Static Mutli-Mobile Agent Itinerary Planning approach (GSMIP). GSMIP applies Directed Acyclic Graph (DAG) related techniques and divide sensor nodes into different groups based on the routes defined by MAs itineraries. MAs follow the predefined routes and only collect data from the groups they are responsible for. The experimental findings demonstrate the effectiveness and superiority of the proposed approach compared to the existing approaches in terms of energy consumption and task delay (time). [ABSTRACT FROM AUTHOR]

Urban rail transit networks seldom provide 24-hour service. The last train is the latest chance for passengers. If passengers arrive too late to catch the last train, the path becomes inaccessible. The network accessibility thus varies depending on the departure time of passenger trips. This paper focuses on the computation method on the time-dependent accessibility of urban rail transit networks in order to facilitate the itinerary planning of passengers. A label setting algorithm is first designed to calculate the latest possible times for Origin-Destination (O-D) pairs, which is the latest departure times of passengers from the origins such that the destinations can be reach successfully. A searching approach is then developed to find the shortest accessible path at any possible departure times. The method is applied in a real-world metro network. The results show that the method is a powerful tool in solving the service accessibility problem. It has the ability to allow passengers to plan an optimal itinerary. Comparison analysis indicates that the proposed method can provide exact solutions in much shorter time, compared with a path enumeration method. Extensive tests on a set of random networks indicate that the method is efficient enough in practical applications. The execution time for an O-D pair on a personal computer with 2.8 GHZ CPU and 4GB of RAM is only 1.2 s for urban rail transit networks with 100 transfer stations. [ABSTRACT FROM AUTHOR]

To control SOx, NOx and particulate matter emission from ships, including cruise ships, emission control areas (ECAs) have been defined by the International Maritime Organization (IMO), which influences cruise planning. This paper investigates a mixed integer programming model to reschedule voyage plans by optimizing speeds, sailing patterns and ports-of-call sequences, hence reducing fuel costs. A tabu search based solution method is developed to solve the model. Computational tests on real-world data of cruise lines are conducted in order to explore the effects of ECA regulations on cruise shipping. The results show that the proposed model can save fuel costs under ECA regulations, and the designed solution method is efficient. [ABSTRACT FROM AUTHOR]

We propose a robust optimization approach to address the itinerary planning problem with deadline in public transit networks. Given departure times at origins and deadlines at destinations, we help the travelers meet the deadlines as much as possible. Our model maximizes the size of the uncertainty set of arc travel times, while guaranteeing that the corresponding worst-case arrival time of itinerary would not exceed the deadline. We exploit the model’s structure and develop efficient solution algorithms. We demonstrate in numerical studies that our approach can effectively mitigate the lateness and can solve real-world instances within one second. [ABSTRACT FROM AUTHOR]

Mobile agent (MA), a part of the mobile computing paradigm, was recently proposed for data gathering in Wireless Sensor Networks (WSNs). The MA-based approach employs two algorithms: Single-agent Itinerary Planning (SIP) and Multi-mobile agent Itinerary Planning (MIP) for energy-efficient data gathering. The MIP was proposed to outperform the weakness of SIP by introducing distributed multi MAs to perform the data gathering task. Despite the advantages of MIP, finding the optimal number of distributed MAs and their itineraries are still regarded as critical issues. The existing MIP algorithms assume that the itinerary of the MA has to start and return back to the sink node. Moreover, each distributed MA has to carry the processing code (data aggregation code) to collect the sensory data and return back to the sink with the accumulated data. However, these assumptions have resulted in an increase in the number of MA's migration hops, which subsequently leads to an increase in energy and time consumption. In this paper, a spawn multi-mobile agent itinerary planning (SMIP) approach is proposed to mitigate the substantial increase in cost of energy and time used in the data gathering processes. The proposed approach is based on the agent spawning such that the main MA is able to spawn other MAs with different tasks assigned from the main MA. Extensive simulation experiments have been conducted to test the performance of the proposed approach against some selected MIP algorithms. The results show that the proposed SMIP outperforms the counterpart algorithms in terms of energy consumption and task delay (time), and improves the integrated energy-delay performance. [ABSTRACT FROM AUTHOR]

This article investigates personal, activity-based tour planning (TP) for tourists in public transportation networks. The objective is to propose an effective framework based on tour parameters, including starting days and times, duration, priority rates of cities, a list of activities and their duration, and a list of transportation means. The subsequent TP should consider the duration of trips to maximize the scores for visiting and acting in a given time frame. In this framework, two nested modules are of primary interest: first, in the main module, the order of the visited cities is determined using a genetic-based strategy; second, in the subordinate module, the shortest path in a multimodal network is obtained based on an adapted Dijkstra algorithm. Since TP is either personal or activity based, constraints of activity duration and periods of enduring activities are considered in the main framework. To evaluate the capabilities of the proposed framework, data are used from real transportation networks in 15 major cities in Iran. Then, several tour planners are employed in order to substantiate the performance of the proposed evolutionary framework. The resulting average relative error of the performed trials is 4.38%, and the simulation therefore vividly demonstrates that the proposed framework is suited for attaining optimum tour plans. [ABSTRACT FROM AUTHOR]

Mobile agent data aggregation routing forwards mobile agents in wireless sensor network to collect and aggregate data. The key objective of data aggregation routing is to maximise the number of collected data samples at the same time as minimising network resource consumption and data collection delay. This paper proposes a mobile agent routing protocol, called zone-based mobile agent aggregation. This protocol utilises a bottom-up mobile agent migration scheme in which the mobile agents start their journeys from the centre of the event regions to the sink aiming to reduce the MA itinerary cost and delay and increase data aggregation routing accuracy. In addition, the proposed protocol reduces the impact of network architecture, event source distribution model and/or data heterogeneity on the performance of data aggregation routing. [ABSTRACT FROM AUTHOR]

Sensor networks are often part of a cyber-physical system. A large-scale sensor network often involves big data collection and data fusion. The agent technology has drawn much attention in wireless sensor networks (WSNs) to perform data fusion and energy balancing. Existing multi-agent itinerary algorithms are either time-consuming or too complicated in practice. In this paper, we design a routing itinerary planning scheme for the multi-agent itinerary problem by constructing the spanning tree of WSN nodes. First, we build a multi-agent-based distributed WSN (DWSN) model and energy consumption model. Second, we present a novel routing itinerary algorithm named DMAIP, which can group all the sensor nodes into multiple itineraries for agents. We also extend DMAIP and design DMAIP-E, which can avoid long-distance transmission in DMAIP. Our evaluation results demonstrate that our algorithms are better in terms of life cycle and energy consumption than the existing DWSN data collecting schemes. [ABSTRACT FROM AUTHOR]

Creating an efficient and economic trip plan is the most annoying job for a backpack traveler. Although travel agency can provide some predefined itineraries, they are not tailored for each specific customer. Previous efforts address the problem by providing an automatic itinerary planning service, which organizes the points-of-interests (POIs) into a customized itinerary. Because the search space of all possible itineraries is too costly to fully explore, to simplify the complexity, most work assume that user's trip is limited to some important POIs and will complete within one day. To address the above limitation, in this paper, we design a more general itinerary planning service, which generates multiday itineraries for the users. In our service, all POIs are considered and ranked based on the users' preference. The problem of searching the optimal itinerary is a team orienteering problem (TOP), a well-known NP-complete problem. To reduce the processing cost, a two-stage planning scheme is proposed. In its preprocessing stage, single-day itineraries are precomputed via the MapReduce jobs. In its online stage, an approximate search algorithm is used to combine the single day itineraries. In this way, we transfer the TOP problem with no polynomial approximation into another NP-complete problem (set-packing problem) with good approximate algorithms. Experiments on real data sets show that our approach can generate high-quality itineraries efficiently. [ABSTRACT FROM AUTHOR]

It has been shown recently that using Mobile Agents (MAs) in wireless sensor networks (WSNs) can help to achieve the flexibility of over-the-air software deployment on demand. In MA-based WSNs, it is crucial to find out an optimal itinerary for an MA to perform data collection from multiple distributed sensors. However, using a single MA brings up the shortcomings such as large latency, inefficient route, and unbalanced resource (e.g. energy) consumption. Then a novel genetic algorithm based multi-agent itinerary planning (GA-MIP) scheme is proposed to address these drawbacks. The extensive simulation experiments show that GA-MIP performs better than the prior single agent algorithms in terms of the product of delay and energy consumption. [ABSTRACT FROM AUTHOR]

Abstract: This paper addresses the problem of time-dependent tour planning in complex and large urban areas that may be of importance for different groups of people. The problem is determination of chronological sequences of attractive points during a specific period via several modes of transportation system. The proposed approach adopted a nested architecture in which tour planning routine calls multimodal shortest path subroutine to generate an itinerary based on user preferences and restrictions of interesting points. Two adapted genetic algorithms were employed in the engine of both blocks. In these algorithms, chromosomes with variable lengths and particularly defined evolutionary stages are used. The proposed process has been tested over the dataset of city of Tehran. The evaluation consists of preparation of 400 tours with different initial points, start time, and tour durations. It was assumed that just three modes of walking, bus, and subway are used to travel between points of interest. Moreover, some tests are applied to dataset to illustrate the adaptability and time-dependency nature of method. The experimental results and related indices such as optimality ratios show that the proposed algorithm can find optimum tour according to introduced constraints. [Copyright &y& Elsevier]

This paper describes journey-planning procedures designed for use in a traveller information system covering fixed-schedule and demand-responsive public transport modes. The task is to construct a sequence of journey-legs to meet a traveller’s requirements with the least possible generalised cost, subject to time-window and other constraints. A journey may be carried out in a single leg by walking or by taking a taxi all the way from the origin to the destination, or by a sequence of one or more legs carried by public transport services sandwiched between walked segments connecting an initial pickup and final setdown stop. The public transport services may include fixed-route modes such as bus and train, and demand-responsive services running between fixed points. The main planning procedures are a high-level request-broker and a branch and bound procedure to handle multi-legged journeys; the request-broker also invokes a fleet-scheduling module to obtain bookings on demand-responsive services. The paper describes planning conditions, the planning procedures, and reduction techniques that are used to obtain acceptable computational performance. Tests with simulated demand suggest that the procedures are well suited for use in a real-time traveller information system. [Copyright &y& Elsevier]

Mobile agent (MA)-based wireless sensor networks present a good alternative to the traditional client/server paradigm. Instead of sending the data gathered by each node to the sink as in client/server, MAs migrate to the sensor nodes (SNs) to collect data, thus reducing energy consumption and bandwidth usage. For MAs, to migrate among SNs, an itinerary should be planned before the migration. Many approaches have been proposed to solve the problem of itinerary planning for MAs, but all of these approaches are based on the assumption that MAs visit all SNs. This assumption, however, is inefficient because of the increasing size of the MAs after visiting each node. Also, in case of node(s) failure, as it is often the case in WSNs, the MAs may not be able to migrate among SNs. None of the proposed approaches takes into consideration the problem of fault tolerance. In this paper, we propose multi-mobile agent itinerary planning-based energy and fault aware data aggregation in wireless sensor networks (MAEF) to plan itineraries for MAs. This can be achieved by grouping nodes in clusters and planning itineraries efficiently among cluster heads (CHs) only. What is more, an alternative itinerary is planned in case of node(s) failure. The simulation result clearly shows that our novel approach performs better than the existing ones. [ABSTRACT FROM AUTHOR]

Recently, wireless sensor networks have employed the concept of mobile agent to reduce energy consumption and obtain effective data gathering. Typically, in data gathering based on mobile agent, it is an important and essential step to find out the optimal itinerary planning for the mobile agent. However, single-agent itinerary planning suffers from two primary disadvantages: task delay and large size of mobile agent as the scale of the network is expanded. Thus, using multi-agent itinerary planning overcomes the drawbacks of single-agent itinerary planning. Despite the advantages of multi-agent itinerary planning, finding the optimal number of distributed mobile agents, source nodes grouping, and optimal itinerary of each mobile agent for simultaneous data gathering are still regarded as critical issues in wireless sensor network. Therefore, in this article, the existing algorithms that have been identified in the literature to address the above issues are reviewed. The review shows that most of the algorithms used one parameter to find the optimal number of mobile agents in multi-agent itinerary planning without utilizing other parameters. More importantly, the review showed that theses algorithms did not take into account the security of the data gathered by the mobile agent. Accordingly, we indicated the limitations of each proposed algorithm and new directions are provided for future research. [ABSTRACT FROM AUTHOR]