Broken Links Research Articles

Research on Stability-Enhanced Clustering Algorithm Based on Distributed Node Status Judgment in MWSN

Node mobility improves the self-deployment capability of the network; meanwhile, it also leads to frequent interruption of communication links and severe packet loss. Mitigating the negative impact of node movement on cluster stability is a new challenge. Existing clustering protocols try to use multi-hop data transmission, but they do not deal with the increase in communication overhead. This paper proposes a distributed node status judgment-based weighted clustering algorithm to solve the problems of easily broken communication links and excessive node reaffiliation in mobile wireless sensor networks (MWSNs). The protocol establishes intra-cluster second-level communication in order to solve the problem of the sudden interruption of dynamic communication links. A node status judgment algorithm was constructed to analyze the motion behavior of sensor nodes, distinguish the node states, and screen multiple communication nodes, thereby alleviating the transmission delay caused by complex routing. The extended Kalman filter (EKF) was used to filter the sensor noise in a non-ideal environment and to predict the actual position of nodes. The simulation results explain that the proposed protocol can effectively reduce node reaffiliation and the dominant set’s update frequency when the node runs at medium and high speeds while simultaneously maintaining low energy consumption.

Making and breaking links: the transformative potential of shared mobility from a practice theories perspective

Shared mobility has the potential to contribute to the transition to a more sustainable mobility system. However, the environmental impacts and the extent of proliferation of the various shared mobility practices differ considerably. It is problematic that the most widespread practice—free-floating carsharing—shows the least environmental potential. Thus, the question arises as to why some shared mobility practices proliferate more readily than others. This paper studies this question from a practice theoretical perspective, focusing on how practices link or do not link with one another. It analyses how various shared mobility practices, as well as the practice of private car travel, connect to other practices via spatial-material and temporal links. The analysis explains why private car travel and, to a lesser degree, free-floating carsharing integrate relatively easily into everyday life, while other forms of shared mobility struggle to do so. This observation leads to the need for far-reaching interventions, both in the making of links of sustainable practices but also in the breaking of links of unsustainable practices. This paper scrutinizes this issue in an anticipatory and theory-based manner and offers suggestions on how to refine practice theoretical concepts regarding inter-practice connections.

Nanoprodrugs encapsulated with mesoporous silica nanoparticles for combined with photothermal therapy for the treatment and care of gastric cancer

In this study, mesoporous silica nanoparticles (MSNs) were surface-modified with polymer poly(HEMA-co-PEGMA via surface-initiated atom transfer radical polymerization and a multifunctional nanoplatform MSNP@poly(HEMA-co-PEGMA-g-doxorubicin (DOX)/Rhodamine 6 G (R6G) was developed to combine photothermal (PTT) and chemotherapy therapy effectively. PTT induced by near-infrared (NIR) radiations might further destroy gastric cancer cell lines while the small-dye molecule was co-loaded into the MSNP pores. A 65 % higher cumulative drug release over 50-h occurs when the cis-aconitic anhydride link breaks under low-pH stimulation (typical physiological environment). High temperatures accelerated reversible covalent bond breakage. The accumulative release of the drug increased by 24.3 %, illustrating that higher temperatures can decrease the time needed to complete blood drug concentrations by 24.3 %. More than 90% of gastric tumour cells were destroyed after 48 h following exposure to NIR light irradiation with the prodrug delivery system, compared to DOX alone in vitro cytotoxicity tests. Because of this, rapidly reversible chemical bond breaking and photothermal activity in MSNP@poly(HEMA-co-PEGMA-g-DOX/R6G) increased the synergic impact of the chemotherapy, which offers tremendous promise in combination with the treatment and care of gastric cancer therapy.

Demonstration of Intelligent Hybrid FSO/RF System Based on Enhanced GRU Prediction and Real-World Meteorological Dataset

Hybrid free space optical (FSO)/radio frequency (RF) system has emerged as a high-data-rate solution for the last mile access network. In this paper, we establish a hybrid FSO/RF testbed including an intensity modulation/direct detection (IM/DD) FSO subsystem with space diversity and a high-order quadrature amplitude modulation (QAM) RF subsystem with polarization diversity, respectively. Based on the testbed, we propose and experimentally validate an intelligent transmission system where the link selection and switching technology is implemented. In particular, we propose a gated recurrent unit (GRU) neural network enhanced by time attention mechanism for the hybrid system. The experimental results demonstrate that the proposed system can achieve the prediction of FSO channel fading with a high precision where absolute percentage error (APE) values lower than 3% account for up to 90% of the prediction results. The implemented intelligent hybrid system can significantly reduce the link switching frequency and link interruption duration. Then the BER is further verified on the testbed, and results show that the intelligent hybrid system can improve the BER from the order of 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−2</sup> to the order of 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−3</sup> during the time periods when link switching occurs.

Analysis of innovation chain structure of global geographic infor-mation industry

Taking the geographic information industry as the research object, using the authorized invention patent data, this paper puts forward the research method of industrial innovation chain structure based on the geographic information industry chain. Then, from the perspective of overall structure and specific regional structure, the development status of the innovation chain is quantitatively evaluated, which is helpful to all countries in the world. The structural integrity and leading links of the innovation chain especially in China, the United States and Japan are compared and analyzed. The results show that: (1) from the perspective of the overall structure, the global innovation chain presents an “inverted triangle” structure due to the weak innovation ability of downstream links. From the perspective of specific regional structure, the innovation chain of geographic information industry in most countries and regions is incomplete, and there are broken links or isolated links. The global innovation chain except China has cracks between the upstream and downstream due to the relative weakness of the midstream links, showing “hourglass-shaped” structure with a wide upper part, narrow lower part and narrow middle part. (2) Relatively speaking, China’s industrial innovation chain is relatively complete, and the midstream link has significant comparative advantages in the global market. However, the industry university research cooperation in the innovation chain is weak, the degree of marketization is low, and the technological competitiveness lags behind that of the United States.

DCM–RPL: A Distributed Competition Mobility Management Scheme for RPL/6LoWPAN

The IPv6 Routing Protocol for Low-Power and Lossy Networks (RPL) as a reliable and energy-efficient routing mechanism has become the de facto standard routing protocol of IPv6 over Low-powered Wireless Personal Area Network (6LoWPAN). However, it is designed for static wireless sensor networks and is not suitable for mobile scenarios. When mobile nodes (MNs) exist in the 6LoWPAN network, repeated link disruptions and topology changes lead to data packets loss and affect network stability. An increasing number of mobile applications force the improvement of RPL protocols for supporting mobility. In this study, a distributed competition and mobility-aware RPL routing protocol (DCM–RPL) is proposed to carry out mobility management and alleviate the network burden in the mobile scenario. A new preferred parent-discovering mechanism for MNs based on a distributed competition algorithm integrated with Objective Function is designed, which can dramatically reduce power consumption in the new parent node (PN)-discovering phase. To reduce data loss during the node-moving process, a packet-caching mechanism is proposed in the PN update phase. Finally, test-beds are set up and simulated in the Cooja simulator. Comparing the performance of the DCM–RPL in terms of switching delay, energy consumption, and PDR with the RPL and its mobility-aware variant (mRPL and EC–MRPL); the simulation results show that the proposed scheme maintains efficiency.

A Fuzzy Linguistic Multi-Criteria Decision-Making Approach to Assess Emergency Suppliers

Under the influence of COVID-19, various emergency supplies have repeatedly broken links, seriously affecting normal life and hindering the sustainable development of enterprises and society. Therefore, suitable emergency suppliers are crucial. To prioritize and select suitable emergency suppliers, key indicators were determined, and evaluation models were established based on the characteristics of epidemic situations and epidemic prevention materials. The application of the MCDM (multi-criteria decision-making) issue combining fuzzy SWARA (the stepwise weight assessment ratio analysis) and the actor analysis method to emergency supplier selection studies, called the fuzzy SWARA-based actor analysis method, is used to identify appropriate suppliers for optimizing pre-preparation. Results of evaluation system weight computations by the Fuzzy SWARA-based actor analysis method show that the overall prioritization of four non-economic factors in ranking orders are “Delivery Capacity”, “Flexible Supply Capacity”, “Quality”, and “Social Evaluation and Reputation”. For the inclusion of conflicting standards and the unquantifiable feature, economic and non-economic factors were discussed separately and evaluated by language variables. Additionally, the fuzzy actor analysis indicated that economic factors and non-economic factors need to be considered comprehensively for emergency supplier selection. This method has good operability and reference value, convenient for the final choice making according to actual situation.

An optimized routing scheme for congestion avoidance using mobile nodes in Wireless Sensor Network

Wireless Sensor Network (WSN) consists of a group of dynamic sensor nodes such nodes form a volatile topology. When an event occurs the dynamic nodes WSN communicate wirelessly from source to destination node without any infrastructure. Dynamic sensor nodes are vital characteristics of WSN where link breakage occurs recurrently and change in topology. Due to this overall network Quality of Service (QoS) degrades due to link failure. Whenever an event in the network experience packet loss due to link failure which leads one of the causes for congestion. However predictable network tries to discover alternate path whenever the link failure occurs on demand which does not have the overall network information thus increasing the communication overhead, delay, and high energy consumption. To address these issues this problem paper proposes an optimized routing scheme known as low latency optimal link-state routing (LL-OLSR) for mobile in WSN which proactively monitors the established path and connects the source to destination with minimum cost with optimal energy. LL-OLSR algorithm finds the disjoint link where it is detected between two nodes and also maximizes the packet delivery ratio by minimizing path delay using connectivity range and queuing delay by which congestion is avoided. Simulation experiment of proposed LL-OLSR scheme is carried on event-driven simulation tool –NS2 and QoS parameters are evaluated by comparing with existing routing scheme.

Getting the GIST: Testing an integrative data structure for linking taxonomy, biodiversity and conservation

Assessing and addressing biodiversity needs are of critical and time-sensitive importance, with the post-2020 Global Biodiversity Framework’s Global Taxonomy Initiative underscoring the need to build capacity in how we conceptualize biodiversity (Abrahamse et al. 2021). Species—as biological units—and their names are the backbone for the data integration and synthesis needed for biodiversity research and conservation decision-making (Grace et al. 2021). In integrating name sources for a single taxonomic group, barriers frequently limit linking species names across regional and global authoritative sources. In response to such challenges, we present a case study testing a Globally Integrated Structure of Taxonomy (GIST) to ensure the integration of taxonomy in biodiversity and conservation sciences. This framework characterizes the components enabling transparent association of species names through synonymy (alternate names or spellings), authorship, specimens, versions and timestamps, and taxonomic relationships in space and time. Taxonomy provides a critical link between biodiversity data types and databases. Efforts towards global taxonomic integration are confounded by insufficient connectivity between taxonomic assemblages, with implications for research, monitoring, and conservation practice (Christie et al. 2021, Jetz et al. 2019, McClure et al. 2020). In attempting to match multiple taxonomic groups across databases, we highlight current progress and remaining challenges to produce and use a GIST. We evaluate the standardized, comprehensive taxonomies of mammals, birds, reptiles, amphibians, dragonflies and damselflies, butterflies, ants, plants, and crabs produced for the Map of Life project (Jetz et al. 2012), identifying which missing components impede their utility. We show that for terrestrial mammals, GIST standards are almost fulfilled, but for invertebrate taxa, such as butterflies, GIST standards are unmet, resulting in broken taxonomic links between aggregators of genetic, spatial, functional, and physical data. We find that even the comprehensive taxonomies we examine do not harmonize well with taxonomies of global genetics, phylogenetics, macroecology, and conservation databases. This is because current taxonomic data infrastructures on biodiversity respositories lack the necessary structural components, searchability, and name source transparency to fully integrate taxonomies, as different independently advancing data sources lack standard metadata practices and operable interfaces. The GIST components enable data linkage and provide clear sourcing and metadata, enabling taxonomic data accessibility, reuse, and interoperability. This structure can act as a step toward open and FAIR (Findable, Accessible, Interoperable, and Reusable) data practice as it relates to taxon names (Wilkinson et al. 2016). Without transparent, integrated, accessible, and updated taxonomic information, macroecological inferences and conservation decisions for even charismatic groups are impeded.

Broken External Links on Stack Overflow

Stack Overflow hosts valuable programming-related knowledge with 11,926,354 links that reference to the third-party websites. The links that reference to the resources hosted outside the Stack Overflow websites extend the Stack Overflow knowledge base substantially. However, with the rapid development of programming-related knowledge, many resources hosted on the Internet are not available anymore. Based on our analysis of the Stack Overflow data that was released on Jun. 2, 2019, 14.2% of the links on Stack Overflow are broken links. The broken links on Stack Overflow can obstruct viewers from obtaining desired programming-related knowledge, and potentially damage the reputation of the Stack Overflow as viewers might regard the posts with broken links as obsolete. In this paper, we characterize the broken links on Stack Overflow. 65% of the broken links in our sampled questions are used to show examples, e.g., code examples. 70% of the broken links in our sampled answers are used to provide supporting information, e.g., explaining a certain concept and describing a step to solve a problem. Only 1.67% of the posts with broken links are highlighted as such by viewers in the posts' comments. Only 5.8% of the posts with broken links removed the broken links. Viewers cannot fully rely on the vote scores to detect broken links, as broken links are common across posts with different vote scores. The websites that host resources that can be maintained by their users are referenced by broken links the most on Stack Overflow -- a prominent example of such websites is GitHub. The posts and comments related to the web technologies, i.e., JavaScript, HTML, CSS, and jQuery, are associated with more broken links. Based on our findings, we shed lights for future directions and provide recommendations for practitioners and researchers.

The Past Web: Exploring Web Archives

The Past Web: Exploring Web Archives

Intelligent Fault-Tolerance Data Routing Scheme for IoT-Enabled WSNs

Wireless sensor networks (WSNs) have become one of the essential components of the Internet of Things (IoT). In any IoT application, different sensor-based devices gather data from physical objects and transmit the sensed information to the base station (BS). The BS analyzes this information depending on the sensor location. A high-performance intelligent WSNs is essential for any IoT-based application. In this article, high-performance intelligent WSNs are referred to as IoT-enabled WSNs. In IoT-enabled WSNs, fault occurrence probability is much more than traditional networks. Faulty nodes and broken links affect the reliability of the IoT-enabled WSNs. Various fault-tolerance algorithms enhance the network’s reliability using multipath transmission, relay node placement, and backup node selection. However, these algorithms suffer from huge data transmission delays, packet overhead, and less detection accuracy. In this work, a multiobjective-deep reinforcement-learning (DRL)-based algorithm is proposed for fault tolerance in IoT-enabled WSNs. The main objective of this work is to detect the faulty nodes with high accuracy and less overhead. Furthermore, this work focuses on reliable data transmission after fault detection. Finally, a mobile sink (MS) is used for energy-efficient data gathering that significantly improves the network lifetime. Extensive simulations and theoretical analysis prove that the proposed algorithm outperformed as compared to the state-of-the-art algorithms in terms of fault detection accuracy (FDA), false alarm rate (FAR), false-positive rate (FPR), network lifetime, and throughput.

Long-term availability of data associated with articles in PLOS ONE.

The adoption of journal policies requiring authors to include a Data Availability Statement has helped to increase the availability of research data associated with research articles. However, having a Data Availability Statement is not a guarantee that readers will be able to locate the data; even if provided with an identifier like a uniform resource locator (URL) or a digital object identifier (DOI), the data may become unavailable due to link rot and content drift. To explore the long-term availability of resources including data, code, and other digital research objects associated with papers, this study extracted 8,503 URLs and DOIs from a corpus of nearly 50,000 Data Availability Statements from papers published in PLOS ONE between 2014 and 2016. These URLs and DOIs were used to attempt to retrieve the data through both automated and manual means. Overall, 80% of the resources could be retrieved automatically, compared to much lower retrieval rates of 10–40% found in previous papers that relied on contacting authors to locate data. Because a URL or DOI might be valid but still not point to the resource, a subset of 350 URLs and 350 DOIs were manually tested, with 78% and 98% of resources, respectively, successfully retrieved. Having a DOI and being shared in a repository were both positively associated with availability. Although resources associated with older papers were slightly less likely to be available, this difference was not statistically significant, suggesting that URLs and DOIs may be an effective means for accessing data over time. These findings point to the value of including URLs and DOIs in Data Availability Statements to ensure access to data on a long-term basis.

A trusted effective approach for forecasting the failure of data link and intrusion in wireless sensor networks

Wireless sensor network (WSN) is often utilised in many different industries for a variety of purposes. The improved network access area and quick network setup make it an excellent technology. However, certain eradicating problems will also be present, slowing the expansion of the network. The forecasting of connection failure is still thought to be a mystery in the WSN area. The suggested method provides a thorough understanding of connection failure. This method introduces the proficient trustworthy Node ID dependent resource reservation protocol (PTN-RRP). Then, using technique weighted on end-to-end latency, the shortest path is identified. Major issues with WSN include data link failure and intrusions. This method might increase the rate of detection since it determines the shortest route from a particular preliminary point to the target. The hop address and sequence number are added to the protocol by determining the shortest path. Following the discovery of the shortest path, the likelihood of connection failure is calculated. The established trustworthy etiquette adopted has a link failure structure that can foresee and resolve connection failure-related problems. After that, a posterior probability evaluation approach is used to determine the type of assault in order to determine the attack reason intended for the connection failure. Finally, a simulation study is used to evaluate the performance of the suggested strategy. The simulation's results show that the proposed technique is extremely successful in identifying link breaks, and the developed algorithm for recognising the shortest path will shorten the time required to find the shortest way. To demonstrate the usefulness of the suggested methodology, the performance result is contrasted with currently used procedures.

Wireless ultraviolet cooperative unmanned aerial vehicle formation communication link maintenance method.

A stable formation communication network can improve the task efficiency of a unmanned aerial vehicle (UAV) cluster. Aiming at the topology construction of the UAV formation communication network, combined with the optimal rigid graph theory, we design a three-dimensional UAV formation communication network generation algorithm based on the optimal rigid graph. We construct a new link weight function by introducing node residual energy and communication path loss to reduce the overall energy consumption of formation. Aiming at the problem that the communication link of the UAV is interrupted when the formation network is moving, a UAV communication beam tracking and holding method based on a multiple-input multiple-output (MIMO) structure and position prediction is designed. Simulation results show that the network topology constructed by the UAV formation communication network generation algorithm has a good average node degree, and effectively improves the network connectivity and communication fault tolerance. Compared with the tracking and holding algorithm based on the received signal strength, the beam tracking and holding algorithm significantly reduces the number of link interruptions, and the communication success holding rate can be basically maintained at about 90%.

Decoherence in the three-state quantum walk

Quantum walks are dynamic systems with a wide range of applications in quantum computation and quantum simulation of analog systems, therefore it is of common interest to understand what changes from an isolated process to one embedded in an environment. In the present work, we analyze the decoherence in a three-state uni-dimensional quantum walk. The approaches taken into consideration to account for the environment effects are phase and amplitude damping Kraus operators, unitary noise on the coin space, and broken links. The results are compared with the two-state quantum walk.

A Modified On-Demand Vector Distance Routing Protocol Incorporating Alternate Vehicle-RSU-Vehicle and Vehicle-RSU- RSU Paths

The Vehicular ad-hoc network (VANET) is an ad-hoc wireless network that allows moving or stationary vehicles to communicate with each other and with the roadside to facilitate various applications, including safety, collision avoidance, and traffic monitoring. The routing protocols provide vehicle-to-vehicle and vehicle-to-roadside communication for the VANET. However, due to the rapid mobility of the vehicles in the network, these protocols suffer from broken links, which leads to unreachable transmission. This paper proposes a new routing protocol based on the ad-hoc on-demand distance vector (AODV) routing protocol to locate the optimal routing of packets in moving vehicles by constructing alternative stable paths with the roadside unit. In the case of the broken links, the alternative stable paths can be used for message transmission, reducing packet discarding. The proposed protocol was simulated, and the results were compared with the original AODV. According to the obtained results, the proposed protocol improves the performance of the AODV in terms of throughput, end-to-end delay, and delivery ratio.

Waypoint segment routing algorithm for LEO satellite network

Satellite communication, especially low earth orbit satellites, an important part of the space-air-ground integrated network, is a promising solution to support global coverage and reliable communication. However, the originally connected links will be off, when the satellites move into polar regions. In addition, the condition of the path broken will dramatically increase with the number of satellites increasing. Thus, it is a continually considerable challenge to design an efficient and stationary routing algorithm for intra-satellites. This paper presents a waypoint segment routing algorithm to realise persistent routes when the satellites move into polar regions. The waypoint selection problem is modelled and solved in stages. One of the source-based routing algorithms, segment routing, is applied in low earth orbit satellite network to provide stable, efficient and reliable packets forwarding. By adding the selected waypoints into the segment list of the segment routing, the next-snapshot broken links can be avoided. Based on the proposed waypoint segment routing algorithm, the problem of the path broken can be effectively solved. By comparing the packet loss, the delay and the delay jitter of the satellite simulation networks, the proposed algorithm is preferable to the popular optimised link-state routing algorithm for the satellite mega-constellation networks.

Usability and accessibility-based quality evaluation of Indian airline websites: An MCDM approach.

A tourist may be one of the most diverse kinds of consumer, including many people with disabilities. As a technologically driven industry, the tourism industry focused more on providing online services during the COVID-19 pandemic, where physical activity is limited and people practice social distancing. A company’s success may be large extend depend on the quality of the website through which they supply their services. The primary goal of the study presented in this paper is to evaluate the overall quality of Indian commercial airline websites. This study evaluated the seven websites of passenger airlines on usability and accessibility parameters using an online diagnostic tool. Page size, load time, response time, broken links, contrast errors were used as the usability parameters, and the TAW tool was used to evaluate the websites’ compliance with WCAG 2.0. The paper proposes a system for determining the best website by utilizing the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS), The Analytic Hierarchy Process (AHP), and the Fuzzy AHP methods. The result shows that Indian airline websites have many usability issues, and none of the websites adheres to WCAG 2.0 accessibility guidelines. Friedman’s test is applied to compare the ranking given by various MCDM techniques, resulting in no significant difference in the various ranking methods adopted.

Online information on medical cannabis is not always aligned with scientific evidence and may raise unrealistic expectations

BackgroundThere is a growing literature on the potential medical uses of Cannabis sativa and cannabinoid compounds. Although these have only been approved by regulatory agencies for a few indications, there is a hype about their possible benefits in a variety of conditions and a large market in the wellness industry. As in many cases patients search for information on cannabis products online, we have analyzed the information on medical cannabis available on the Internet. Therefore, this study aims at assessing the quality of the information available online on medical cannabis.MethodsWe searched “medical cannabis” on June 2019 using google.com and downloaded the first 243 websites. After excluding dead links or websites with no information about cannabis, 176 websites were included. They were then classified for their typology (e.g., commercial, government, news outlets). As an indicator of trustworthiness, we used the Journal of American Medical Association (JAMA) score, which assesses the indication of date, author, ownership of the website, and the presence of references. We also considered if a website is certified by Health-On-the-Net (HON), an independent organization, by displaying a HONCode symbol. Subsequently, we performed a content analysis to assess both the medical cannabis indications mentioned by webpages and the completeness of the information provided (whether they mentioned potential side effects and legal/regulatory issues or not).ResultsAnalyzing 176 webpages returned by a search engine, we found that 52% of them were news websites. Pain, epilepsy, and multiple sclerosis were the most frequently mentioned therapeutic areas (cited in 92, 84 and 80 webpages, respectively), which did not always match those for which there is regulatory approval. Information was also incomplete, with only 22% of the webpages mentioning potential side effects. Health portal websites provided the most complete information, with all of them (n = 7) reporting side effects. On average, 80% of webpages had a neutral stance on the potential benefits of medical cannabis, with commercial websites having more frequently a positive stance (67%).ConclusionsWe conclude that the information that can be found online is not always aligned in terms of the therapeutic areas for which science-based evidence is often still weak.