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Vertical handover has been grown rapidly due to the mobility model improvements. These improvements are limited to certain circumstances and do not provide the support in the generic mobility, but offering vertical handover management in HetNets is very crucial and challenging. Therefore, this paper presents a vertical handoff management method using the effective network identification method.

This paper presents a vertical handoff management method using the effective network identification method. The handover triggering schemes are initially modeled to find the suitable position for starting handover using computed coverage area of the WLAN access point or cellular base station. Consequently, inappropriate networks are removed to determine the optimal network for performing the handover process. Accordingly, the network identification approach is introduced based on an adaptive particle-based Sailfish optimizer (APBSO). The APBSO is newly designed by incorporating self-adaptive particle swarm optimization (APSO) in Sailfish optimizer (SFO) and hence, modifying the update rule of the APBSO algorithm based on the location of the solutions in the past iterations. Also, the proposed APBSO is utilized for training deep-stacked autoencoder to choose the optimal weights. Several parameters, like end to end (E2E) delay, jitter, signal-to-interference-plus-noise ratio (SINR), packet loss, handover probability (HOP) are considered to find the best network.

The developed APBSO-based deep stacked autoencoder outperformed than other methods with a minimal delay of 11.37 ms, minimal HOP of 0.312, maximal stay time of 7.793 s and maximal throughput of 12.726 Mbps, respectively.

The network identification approach is introduced based on an APBSO. The APBSO is newly designed by incorporating self-APSO in SFO and hence, modifying the update rule of the APBSO algorithm based on the location of the solutions in the past iterations. Also, the proposed APBSO is used for training deep-stacked autoencoder to choose the optimal weights. Several parameters, like E2E delay, jitter, SINR, packet loss and HOP are considered to find the best network. The developed APBSO-based deep stacked autoencoder outperformed than other methods with minimal delay minimal HOP, maximal stay time and maximal throughput.

Process mining provides a new means to improve processes in a variety of application domains. The purpose of this paper is to abstract a process model and then use the discovered models from process mining to make useful optimization via predictions.

The paper divides the process model into a combination of “pair-adjacent activities” and “pair-adjacent persons” in the event logs. First, two new handover process models based on adjacency matrix are proposed. Second, by adding the stage, frequency, and time for every activity or person into the matrix, another two new handover prediction process models based on stage adjacency matrix are further proposed. Third, compute the conditional probability from every stage to next stage through the frequency. Finally, use real data to analyze and demonstrate the practicality and effectiveness of the proposed handover optimization process.

The process model can be extended with information to predict what will actually happen, how possible to reach the next activity, who will do this activity, and the corresponding probability if there are several people executing the same activity, etc.

The contribution of this paper is to predict what will actually happen, how possible it is to reach the following activities or persons in the next stage, how soon to reach the following activities or persons by calculating all the possible interval time via different traces, who will do this activity, and the corresponding probability if there are several people executing the same activity, etc.

In the past, by adopting the handover prediction concept of the fast mobile IPv6, the authors have proposed a cross-layer architecture, which was called the proactive fast HCoP-B (FHCoP-B), to trigger layer 3 HCoP-B route optimization flow by 802.11 and 802.16 link events before the actual layer 2 handover of a mobile subnet in the nested mobile network (NEMO) occurs. In this way, proactive FHCoP-B has shortened its handover latency and packet loss. However, there are two scenarios where proactive FHCoP-B cannot normally complete its operations due to fast movements of the NEMO during handover. The paper aims to discuss these issues.

In this paper, the authors will propose efficient reactive FHCoP-B flows for these two scenarios to support fast and seamless handovers. The authors will further extend the analytical model proposed for mobile IPv6 to investigate four performance metrics of proactive and reactive FHCoP-B, HCoP-B and two well-known NEMO schemes with the radio link protocol (RLP), which can detect packet losses and performs retransmissions over the error-prone wireless link.

Through intensive simulations, the authors conclude that FHCoP-B outperforms HCoP-B and the other two well-known NEMO schemes by achieving the shortest handover latencies, the smallest number of packet losses and the fewest playback interruption time during handover only with few extra buffer spaces, even over error-prone wireless links of the nested NEMO.

This paper has three major contributions, which are rare in the NEMO literature. First, the proactive FHCoP-B has been enhanced as the reactive one to handle two fast handover scenarios with RLP for the nested NEMO. Second, the reactive FHCoP-B supports seamless reactive handover for the nested NEMO over error-prone wireless links. Third, mathematical performance analyses for two scenarios of reactive FHCoP-B with RLP over error-prone wireless links have been conducted.

The paper aims to propose an optimized handover necessity estimation scheme for a mobile terminal (MT) traversing from a third-generation (3G) cellular network into the wireless local area network (WLAN) cell for reducing the number of handover failures and unnecessary handovers.

The proposed optimized handover necessity estimation scheme comprises of two algorithms – a “travelling time prediction” reliant on consecutive received signal strength (RSS) measurements and MT’s velocity, and a “time threshold estimation” depending on the handover latency, WLAN’s cell radius, tolerable handover failure probability and the tolerable unnecessary handover probability.

Our performance analysis reveals that the suggested mechanism effectively minimizes the number of handover failures and unnecessary handovers by 60 per cent as compared to the already proposed schemes in the literature.

The convergence of Internet and wireless mobile communication accompanied by a massive increase in the number of cellular subscribers has led mobility management to emerge as a significant and challenging domain for wireless mobile communication over the Internet. Mobility management enables serving networks to locate roaming terminals for the call delivery (location management) and ensures a seamless connection as MT enters into the new service area (handover management). In this manuscript, an optimized handover necessity estimation scheme has been envisaged for reducing the probability of handover failures and unnecessary handovers from 3G cellular networks to WLANs to provide optimal network utilization along with an enhanced user satisfaction. Performance analysis reveals that the suggested scheme yields enhanced results as compared to the schemes already proposed in the literature.

This paper aims to describe the development of guidance to help clients and operational teams to clearly define information requirements for projects using building information modelling (BIM). ISO 19650 standards highlight this as a critical first step to ensure adequate information is available to optimise built assets over their whole life cycle.

A document analysis of existing BIM guidance supported by literature was undertaken to answer the research questions: “What guidance already exists specific to clients? and Would additional guidance help clients to better fulfil their role as the ‘appointing party’ in line with ISO 19650?”

A research gap was established highlighting a lack of guidance specifically aimed to help clients formulate information requirements as the appointing party. This research makes recommendations for an approach to define the requirements and support successful outcomes for BIM projects.

This paper provides a standardised approach and a starting point for an appointing party to gather and structure information requirements in line with ISO 19650.

This paper considers BIM information requirements specifically from an operations perspective with a focus on the client and facility management team.

A lot of recent research has been focused on developing network mobility management to support the movement of a mobile network consisting of several mobile nodes. The IETF NEMO working group proposed the NEMO basic support protocol that defines a methodology for supporting such network mobility using bi‐directional tunneling between the home agent and the mobile router. However, this protocol has been found to suffer from the so‐called ‘dog‐leg problem’, and despite alternative research efforts to solve this problem, there are still limitations in the efficiency of real time data transmission and intra‐domain communication. Accordingly, the current paper proposes a new route optimization methodology that uses unidirectional tunneling and a tree‐based intra‐domain routing mechanism. As such, the proposed scheme can provide faster signaling and data transmission and be easily extended to support micro‐mobility without any additional extensions. The performance of the proposed scheme is also evaluated to demonstrate its efficiency.

Fifth-generation (5G) networks play a significant role in handover methods. 5G wireless network is open, flexible and highly heterogeneous along with the overlay coverage and small cell deployments. Handover management is one of the main problems in the heterogeneous network. Also, handover satisfies the needs of ultra-reliable communications along with very high reliability and availability in 5G networks. Handover management deals with every active connection of a user’s device, which moves the connection between the user’s device and the counterparty from one network point to another. Thus, the handover decision determines the best access network and also decides whether the handover is performed or not.

The main intention of this survey is to review several existing handover technologies in 5G. Using the categories of analysis, the existing techniques are divided into different techniques such as authentication-based techniques, blockchain-based techniques, software-defined-based techniques and radio access-based techniques. The survey is made by considering the methods such as used software, categorization of methods and used in the research works. Furthermore, the handover rate is considered for performance evaluation for the handover techniques in 5G. The drawbacks present in the existing review papers are elaborated in research gaps and issues division.

Through the detailed analysis and discussion, it can be summarized that the widely concerned evaluation metric for the performance evaluation is the handover rate. It is exploited that the handover rate within the range of 91%–99% is achieved by three research papers.

A survey on the various handover mechanisms in 5G networks is expected in this study. The research papers used in this survey are gathered from different sources such as Google Scholar and IEEE. Also, this survey suggests a further extension for the handover mechanism in 5G networks by considering various research gaps and issues.

Vertical handoff mechanism (VHO) becomes very popular because of the improvements in the mobility models. These developments are less to certain circumstances and thus do not provide support in generic mobility, but the vertical handover management providing in the heterogeneous wireless networks (HWNs) is crucial and challenging. Hence, this paper introduces the vertical handoff management approach based on an effective network selection scheme.

This paper aims to improve the working principle of previous methods and make VHO more efficient and reliable for the HWN.Initially, the handover triggering techniques is modelled for identifying an appropriate place to initiate handover based on the computed coverage area of cellular base station or wireless local area network (WLAN) access point. Then, inappropriate networks are eliminated for determining the better network to perform handover. Accordingly, a network selection approach is introduced on the basis ofthe Fractional-dolphin echolocation-based support vector neural network (Fractional-DE-based SVNN). The Fractional-DE is designed by integrating Fractional calculus (FC) in Dolphin echolocation (DE), and thereby, modifying the update rule of the DE algorithm based on the location of the solutions in past iterations. The proposed Fractional-DE algorithm is used to train Support vector neural network (SVNN) for selecting the best weights. Several parameters, like Bit error rate (BER), End to end delay (EED), jitter, packet loss, and energy consumption are considered for choosing the best network.

The performance of the proposed VHO mechanism based on Fractional-DE is evaluated based on delay, energy consumption, staytime, and throughput. The proposed Fractional-DE method achieves the minimal delay of 0.0100 sec, the minimal energy consumption of 0.348, maximal staytime of 4.373 sec, and the maximal throughput of 109.20 kbps.

In this paper, a network selection approach is introduced on the basis of the Fractional-Dolphin Echolocation-based Support vector neural network (Fractional-DE-based SVNN). The Fractional-DE is designed by integrating Fractional calculus (FC) in Dolphin echolocation (DE), and thereby, modifying the update rule of the DE algorithm based on the location of the solutions in past iterations. The proposed Fractional-DE algorithm is used to train SVNN for selecting the best weights. Several parameters, like Bit error rate (BER), End to end delay (EED), jitter, packet loss, and energy consumption are considered for choosing the best network.The performance of the proposed VHO mechanism based on Fractional-DE is evaluated based on delay, energy consumption, staytime, and throughput, in which the proposed method offers the best performance.

As the use of building information modeling (BIM) for facilities management (FM) continues to grow, questions remain around the quality and completeness of digital assets to support FM practices. This paper aims to examine the current gap between digital and physical assets in the absence of formal information requirements and its impact on the handover process.

An action-research was carried out with a large public organization to understand the challenges of their current FM processes and the steps required in developing an asset information model (AIM) from a project information model (PIM). A mixed method approach was employed with interviews, document analysis and an exploratory pilot case study.

This paper investigates the process, the challenges and the level of effort of the information commissioning process to create a fit-for-use AIM. Four distinct steps were identified in the process as follows: analyzing the handover PIM and documents, extracting FM-specific information, populating the model with the information and attaching operations and maintenance (O&M) documents. The research highlights the significant amount of effort that is required when no specific asset information requirements are formulated at the project onset.

The paper presents an information commissioning process that helps to develop an AIM from a PIM. Understanding the impact of the lack of requirements on the information commissioning process can help asset owners understand the importance of defining and articulating their information requirements up front.

This paper provides empirical evidence of the impact of the absence of formal information requirements on the development of a fit-for-use AIM.

This study presented the experience of improving the nucleic acid sample collection and transportation service in response to the epidemic. The main purpose is that through intelligent path planning, combined with the time scheduling of sample points, the process of obtaining results to determine the state of COVID-19 patients could be speeding up.

The research optimized the process, including finding an optimal path to traverse all sample points in the hospital area via intelligent path planning method and standardizing the operation through the time sequence scheduling of each round of support staff to collect and send samples in the hospital area, so as to ensure the shortest time in each round. And the study examines these real-time experiments through retrospective examination.

The real-time experiments' data showed that the proposed path planning and scheduling model could provide a reliable reference for improving the efficiency of hospital logistics. Testing is a very important part of diagnosis and prompt results are essential. It shows the possibility of applying the shortest-path algorithms to optimize sample collection processes in the hospital and presents the case study that gives the expected outcomes of such a process.

The value of the study lies in the abstraction of a very practical and urgent problem into a TSP. Combining the ant colony algorithm with the genetic algorithm (ACAGA), the performance of path planning is improved. Under the intervention and guidance, the efficiency of hospital regional logistics planning was greatly improved, which may be of greater benefit to critical patients who must go through fever clinic during the epidemic. By detailing how to more rapidly obtain results through engineering method, the paper contributes ideas and plans for practitioners to use. The experience and lessons learned from Tongji Hospital are expected to provide guidance for supporting service measures in national public health infrastructure management and valuable reference for the development of hospitals in other countries or regions.