High-throughput Routing Research Articles

Enabling High-Throughput Routing for LEO Satellite Broadband Networks: A Flow-Centric Deep Reinforcement Learning Approach

Enabling High-Throughput Routing for LEO Satellite Broadband Networks: A Flow-Centric Deep Reinforcement Learning Approach

Adaptive Multi-Path Routing Protocol in Autonomous Vehicular Networks

Vehicular ad hoc networks consist of self-organizing nodes using multi-hop wireless links for communication without any infrastructure support. Traditionally, ad hoc routing protocols use the minimum hop count for their routing metric since a smaller number of transmissions is typically equivalent to a higher throughput, lower delay, and minimal power consumption. However, with the muti-rate capability of emerging radio interfaces, e.g., 802.11ax/be standards, the min-hop metric no longer results in high throughput. For instance, if the higher data rate links are selected for the route, it could result in a higher throughput even if the route takes more hop counts. In this paper, we propose a high throughput routing scheme, called MARV, which makes two key contributions. MARV searches for high throughput paths using an on-demand route searching algorithm so that the routing overhead is smaller compared to other multi-rate-aware routing schemes. MARV also searches for multiple paths to maintain both min-hop and high-throughput paths to select the adequate path depending on the data packet size. We conduct simulations to demonstrate that MARV outperforms not only min-hop path metrics but also previously proposed high-throughput metrics.

Ultrasensitive proteomics depicted an in-depth landscape for the very early stage of mouse maternal-to-zygotic transition

Single-cell or low-input multi-omics techniques have revolutionized the study of pre-implantation embryo development. However, the single-cell or low-input proteomic research in this field is relatively underdeveloped because of the higher threshold of the starting material for mammalian embryo samples and the lack of hypersensitive proteome technology. In this study, a comprehensive solution of ultrasensitive proteome technology (CS-UPT) was developed for single-cell or low-input mouse oocyte/embryo samples. The deep coverage and high-throughput routes significantly reduced the starting material and were selected by investigators based on their demands. Using the deep coverage route, we provided the first large-scale snapshot of the very early stage of mouse maternal-to-zygotic transition, including almost 5,500 protein groups from 20 mouse oocytes or zygotes for each sample. Moreover, significant protein regulatory networks centered on transcription factors and kinases between the MII oocyte and 1-cell embryo provided rich insights into minor zygotic genome activation.

Effects of Carbon Nanotube Diameter on the Fabrication and Performance of Collagen-Inspired Carbon Nanotube Films

High-performance carbon nanotube (CNT) fibers have long been pursued in many academic and industrial communities, and recent decades have witnessed continuous progress in the CNT fiber design and fabrication, although their commercial applications have not been well realized. Inspired by the microstructure of type I collagen fibers, we have proposed a high-throughput route to fabricate CNT fibers/ films by domino-pushing and ion bombarding as-grown CNT forest. With CNTs of small diameter, numerical simulations have demonstrated that the route can well produce collagen-mimicked high-performance CNT fibers with unidirectionally aligned and transversally crosslinked CNTs. As CNT diameter increases, the complex mechanical behaviors such as collapse will probably occur, and hence the influence of the CNT diameter on the fabrication and performance of the fibers needs to be further studied. This work revealed that during the fabrication process the round-to-dumbbell CNT collapse happens with their diameter larger than 2[Formula: see text]nm. Before the collapse, the mechanical performance of the acquired CNT fibers decreases with CNT diameter, but reverses to increase after the collapse, mainly due to the reversed porosity-diameter relation by the collapse behavior. The varying of the fiber mechanical properties with the bombardment energy and dosage was also shown for different CNT diameters. Further, some useful guidelines on the mechanical property and fabrication process design of the bioinspired CNT fibers are concluded.

Recovery of Cobalt from Lithium-Ion Batteries Using Fluidised Cathode Molten Salt Electrolysis

Within the next 30 years, the number of vehicles powered by electricity is predicted to rise to 1 billion representing an exponential increase from 7.9 million used in 2019 [1]. These electrified vehicles will rely on lithium-ion rechargeable batteries with projections augmented by the impending ban on new petrol and diesel car sales. Despite these batteries offering a green, carbon-free alternative they remain overshadowed by the sustainable use of raw materials. Thus, the future need to recycle enormous quantities of Li-ion batteries arises because of the projected increase in the electrified fleet of vehicles required to decarbonise the transport sector. Cobalt is an essential element in several Li-ion battery cathode chemistries (e.g. NMC, NCA and LCO). In this study, we present an electrochemical reduction process of LiCoO2 to Co using a molten salt fluidised cathode technique at 450 oC [2]. Using thermodynamic calculations, a predominance diagram was constructed in Figure 1 to aid in understanding the reduction pathway. Cyclic voltammograms indicate two 2-electron transfer steps, the first where Co3O4 is reduced to CoO at −0.55 V vs Ag/Ag+ followed by the second reduction step of CoO to Co at −2.4 V vs. Ag/Ag+. The reduction potential of Co was used to determine the input parameters in the current versus time profiles. The Faradaic current efficiencies for both the commercially obtained LiCoO2 and spent Li-ion battery yield values greater than 70%. Thus, the fluidised cathode technique could prove to be an energy-efficient and high-throughput route for the recovery of cobalt, in this work, as well as different materials found in other batteries. Gielen, R. Gorini, N. Wagner, R. Leme and G. Prakash. International Renewable Energy Agency (IRENA), Global Renewables Outlook: Energy Transformation 2050, Abu Dhabi, Edition: 2020.M. Mirza, R. Abdulaziz, W.C. Maskell, C. Tan, P.R. Shearing, D.J.L. Brett, Recovery of cobalt from lithium-ion batteries using fluidised cathode molten salt electrolysis, Electrochim. Acta. 391 (2021) 138846. Figure 1

A High-Performance Energy-Balanced Forwarding Strategy for Wireless Sensor Networks

The wireless sensor network (WSN) is composed of several sensor nodes organized by multi-hop self-organization, which is a typical network for the industrial internet in industrial application. However, the energy using and processing capacity of each node are greatly limited. Therefore, it is of great significance to study energy-saving and efficient communication protocols for WSN. To prolong the lifetime of WSN and improve network throughput, a high throughput routing protocol with balanced energy consumption is proposed. The designed protocol first employs the K-means clustering algorithm to cluster the nodes, then calculates the weights based on the residual energy of and distance between the nodes, and finally selects the best node as the cluster head. Moreover, the optimal size of the package is determined by the parameters of the wireless transceiver and the channel conditions. In the data transmission stage, the Dijkstra algorithm is used to calculate the multi-objective weight function as the link cost. Experimental results demonstrate the superior performance of the proposed protocol over the CERP and TEEN routing protocols in terms of energy saving of network nodes, so as to improve the throughput and survival time of the entire system.

Synthesis and characterisation of Ce-doped zirconolite Ca0.80Ce0.20ZrTi1.60M0.40O7 (M\u2009=\u2009Fe, Al) formed by reactive spark plasma sintering (RSPS)

Reactive spark plasma sintering has been utilised as a high-throughput processing route for the synthesis of two simulant zirconolite wasteform materials, targeting Ca0.80Ce0.20ZrTi1.60M0.40O7 (M = Fe3+ and Al3+). Materials were processed under 15 MPa uniaxial pressure, with heating/cooling rates of 100 °C/min to 1320 °C, maintained under vacuum. Despite moderate yield (> 80 wt%) of zirconolite-2M, a considerable Ce-rich perovskite phase was formed in both formulations, attributed to complete reduction of the Ce inventory to Ce3+, as determined by Ce L3-edge XANES analysis. The composition charge balanced with Al3+ was favoured on the basis of lower accompanying perovskite fraction.Graphical abstract

Recovery of cobalt from lithium-ion batteries using fluidised cathode molten salt electrolysis

The future need to recycle enormous quantities of Li-ion batteries is a consequence of the rapid rise in electric vehicles required to decarbonise the transport sector. Cobalt is a critical element in many Li-ion battery cathode chemistries. Herein, an electrochemical reduction and recovery process of Co from LiCoO2 is demonstrated that uses a molten salt fluidised cathode technique. For the Li-Co-O-Cl system, specific to the experimental process, a predominance diagram was developed to aid in understanding the reduction pathway. The voltammograms indicate two 2-electron transfer reactions and the reduction of CoO to Co at −2.4 V vs. Ag/Ag+. Chronoamperometry revealed a Faradaic current efficiency estimated between 70-80% for the commercially-obtained LiCoO2 and upwards of 80% for the spent Li-ion battery. The molten salt electrochemical process route for the recycling of spent Li-ion batteries could prove to be a simple, green and high-throughput route for the efficient recovery of critical materials.

Reliable and QoS aware routing metrics for wireless Neighborhood Area Networking in smart grids

Smart Grid networks use data collected from sensors in evaluating the current system state to make optimal resource distribution decisions and facilitate two-way energy exchange. Efficient and timely communication between smart grid assets using high efficiency and reliable Neighborhood Area Network (NAN) for the last-mile can play a significantly important role. For this requirement, wireless mesh networking can be used to offer scalable, flexible and resilient wireless connectivity. Despite significant advantages and tremendous applications, smart grid NANs are vulnerable to security and reliability issues during electric power delivery. After being compromised by an adversary, cascading-failure-induced disasters may disrupt the power grid from a remote location; customer’s private information may become vulnerable if accessed illegally; the adversary may also compromise selected nodes (change the normal behavior of a node to malicious behavior) and thus fail the critical mission of the Supervisory Control and Data Acquisition (SCADA) system. Moreover, the Enhanced Distributed Channel Access (EDCA) mechanism of IEEE 802.11e wireless technology can be leveraged for service differentiation based routing among flows of differing priorities. Routing decisions in mesh networks are based on routing metrics which have been the focus of research for the past decade. However, NANs offer a different implementation scenario from traditional mesh infrastructures and also necessitate the need for differentiated quality of service. In this paper, we discuss how state-of-the-art routing metrics have limitations for the NAN scenario, especially for EDCA based differentiated access. Moreover, we propose and design a secure and EDCA based contention-aware routing approach - iRoute, for 802.11e based wireless NANs which enables the selection of reliable routes that also satisfy QoS requirements (low contention, high throughput routes). Simulation-based performance evaluation of the proposed approach shows that it can provide significantly better performance in terms of throughput and delay for NAN communication.

Volcano Routing: A Multi-Pipe High-Throughput Routing Protocol with Hole Avoidance for Multi-Beam Directional Mesh Networks

The emergence of multi-beam directional antennas (MBDAs) has paved the way for fast and high-throughput data communications by providing concurrent multi-directional transmissions. However, the existing routing protocols are not capable of utilizing the advantages of MBDAs. In this paper, we have developed a new routing scheme, called volcano routing, which can exploit the concurrent packet dispatching capability of MBDAs for high-throughput data delivery. Its topology resembles the flow of volcano lava and several routing “pipes” are used, which can detour around the network “holes” or blocked areas. The routing process consists of two phases: 1) Main path search phase: There is a main path at the core of each pipe. Multiple optimal main paths are formed that have a high potential of adding side nodes to enable multi-beam communications. A hierarchical scoring system and the performance metrics are used to evaluate the quality of the main paths. 2) Volcano establishment phase: The top-quality main paths are selected, and side paths are formed around each main path to establish the volcano pipes. A multi-beam traffic scheduling and dispatching policy is also proposed to achieve better performance. Our results show that the volcano routing scheme can exploit the advantages of MBDAs for achieving high data rates.

Hydroxypropyl Cellulose Adhesives for Transfer Printing of Carbon Nanotubes and Metallic Nanostructures.

Transfer printing is one of the key nanofabrication techniques for the large-scale manufacturing of complex device architectures. It provides acost-effective and high-throughput route for the integration of independently processed materials into spatially tailored architectures. Furthermore, this method enables the fabrication of flexible and curvilinear devices, paving the way for the fabrication of a new generation of technologies for optics, electronics, and biomedicine. In this work, hydroxypropyl cellulose (HPC) membranes are used as water soluble adhesives for transfer printing processes with improved performance and versatility compared to conventional silicone alternatives. The high-water solubility and excellent mechanical properties of HPC facilitate transfer printing with high yield for both metal and carbon nanotubes (CNTs) inks. In the case of metal inks, crack-free stripping of silver films and the simple fabrication of Moiré Plasmonic architectures of different geometries are demonstrated. Furthermore, HPC membranes are used to transfer print carbon nanotube films with different thicknesses and up to 77% transparency in the visible and near infrared region with potential applications as transparent conductive substrates. Finally, the use of prepatterned HPC membranes enables nanoscale patterning of CNT with feature resolution down to 1µm.

EH-UWSN: Improved Cooperative Routing Scheme for UWSNs Using Energy Harvesting

The harsh testing environments of underwater scenarios make it extremely hard to plan a reasonable routing protocol for Underwater Sensor Networks (UWSNs). The main challenge in UWSNs is energy confinement. It is needed to plan an energy effective scheme which increases the life span of the network and also reduces the energy usage in data transfer from supplier to sink. In this research, we present the design of a routing protocol known as Energy Harvesting in UWSN (EH-UWSN). EH-UWSN is a compact, energy efficient, and high throughput routing protocol, in which we present utilization of energy gaining with coordinating transfer of data packets through relay nodes. Through Energy Harvesting, the nodes are capable to recharge their batteries from the outside surrounding with the ultimate objective to improve the time span of network and proceed data through cooperation, along with restricting energy usage. At the sink node, the mixing plan applied is centered on Signal-to-Noise Ratio Combination (SNRC). Outcomes of EH-UWSN procedure reveal good results in terms of usage of energy, throughput, and network life span in comparing with our previous Cooperative Routing Scheme for UWSNs (Co-UWSN). Simulation results show that EH-UWSN has consumed considerably lesser energy when compared with Co-UWSN along with extending network lifetime and higher throughput at the destination.

1000-Pixels per Inch Transistor Arrays Using Multi-Level Imprint Lithography

Sub-micrometer thin-film transistors (TFTs) are realized using multi-level imprint lithography. Amorphous indium gallium zinc oxide ( $\alpha $ -IGZO) TFTs with channel lengths as small as $0.7~\mu \text{m}$ , field-effect mobility of 10 cm2V−1s−1 and on/off ratio of circa 107 were integrated into a 1000-pixels per inch (ppi) TFT backplane array. The reduction of the number of patterning steps and the inherent self-registration of the most critical transistor layers on top of each other offer a cost-effective high-throughput fabrication route for high-resolution TFT arrays.

Ultrasensitive monitoring of DNA damage associated with free radicals exposure using dynamic carbon nanotubes bridged interdigitated electrode array

There are currently increasingly concerns over DNA damage related to free radicals due to their vital roles in human health, especially high-performance detection method. Herein, we report an ultra- sensitive monitoring of DNA damage associated with free radicals exposure using interdigitated electrode (IDE) array for the first time. The proposed IDE array was equipped with DNA-wrapped carbon nanotube-based bridges, which utilized the DNA damage mechanism due to the free radicals’ attack and the efficient electrical detection nature of the interdigitated electrode. Experiments have been performed, and the results showed the device’s capability for detecting DNA damage induced by multiple free radicals generated from different sources, including the Fenton reaction, UV radiation and cigarette smoke, showing the promising ability for DNA damage detection. In addition, the carbon nanotubes bridge-based interdigitated electrode sensor enabled different levels of sensing of DNA damage with great sensitivity and a wide detection range. It was illustrated that the ultrasensitive detection of free radicals generated from ultraviolet radiation (15 min – 125 min), cigarette smoke tar (1 μg/mL to 10 μg/mL) and Fenton reaction under different concentration of H2O2 (2.5 pM – 100 pM), have been detected successfully. Typically, the IDE array supports further performance improvement for the electrochemical detection in an ultrasensitive and high throughput route.

A Potential High-Throughput Route to Collagen-Mimicked Carbon Nanotube Fiber via Domino Pushing and Ion Bombardment

Abstract Carbon nanotubes (CNTs) have been shown owning extraordinary mechanical properties for decades, but to date, their wide application as load-bearing structural materials has not been realized mainly due to the critical obstacles of weak interface, poor distribution and alignment, and lack of economic technology for mass production and processing. In order to overcome these obstacles, we proposed a potential route from as-grown CNT forest to collagen-mimicked CNT films with covalently crosslinked CNTs arranged in a staggered alignment. To consolidate the foundation of the route, its critical step of ion bombardment to construct the intertube crosslinks in CNT films was simulated using molecular dynamics simulations. Results show that the ion bombardment can efficiently construct the intertube crosslinks and greatly improve the elastic modulus and strength of CNT films by as much as 24% and 660%, respectively, with comparison to the nonbombarded ones. The influences of the number and the kinetic energy of the incident particles were systematically investigated and the corresponding contours were presented, suggesting the optimal energy and number of the incident particles for the elastic modulus and strength of collagen-mimicked CNT films. The work not only provides a novel route to mass fabrication of high-performance CNT fibers but also gives useful guidelines on the optimization of processing design.

Bimodal Nanofiber and Microfiber Nonwovens by Melt-Blowing Immiscible Ternary Polymer Blends

Most nonwoven fiber mats are produced with a uniform, narrow fiber diameter distribution. However, building evidence suggests that a bimodal diameter distribution (i.e., comprised of two populations of fibers, one with a smaller average diameter (dₐᵥ), d, and the other with a larger dₐᵥ, D, where D ≥ 5d), has certain advantages in applications such as filtration media. To the best of our knowledge, all previous reports describing production of bimodal fiber diameter distributions have relied on solution-based electrospinning, a much less common fiber-spinning technique, compared to melt blowing, which currently produces more than 10% of nonwovens globally (an approximately $50 billion market). In this study, we demonstrate a facile method for producing bimodal fiber diameter distributions by melt blowing immiscible ternary polymer blends, with the two minority blend components being randomly dispersed as isolated, bimodally sized particles within the continuous matrix. Such a ternary blend can be obtained by selecting a matrix phase that preferentially wets/encapsulates both dispersed phases having vastly different viscosity ratios. Specifically, two model immiscible ternary blends comprised of polystyrene/polyethylene/Nylon-6 (PS/PE/Nylon) and poly(ethylene oxide)/polyethylene/Nylon-6 (PEO/PE/Nylon) with the desired morphologies and PS or PEO as the matrix were examined. During melt blowing of the blends, the PE minority domains (∼8 μm in diameter) and Nylon minority domains (∼70 μm in diameter) dispersed within the matrix were transformed to PE nanofibers (dₐᵥ ≈ 560 nm) and Nylon microfibers (dₐᵥ ≈ 8 μm) embedded in the elongated PS matrix fibers, and similarly for fibers made with a PEO matrix. Subsequent removal of the matrix polymer with an appropriate solvent (tetrahydrofuran for PS or water for PEO) produced a macroscopic mat of randomly distributed, bimodal nanofibers and microfibers. The nanofiber and microfiber compositions of the bimodal-diameter fiber mats were effectively tuned by varying the composition of the minority components of the original ternary polymer blends. Interestingly, the resulting bimodal-diameter fiber mats possessed few nanofiber bundles; we hypothesize that this is due to the presence of Nylon microfibers that are intrinsically intermixed among the PE nanofibers that physically restrict the formation of nanofiber bundles. Overall, this versatile method could provide a high-throughput route to scalable quantities of fiber mats with a bimodal distribution of fiber diameters, thus promoting the application of hierarchically structured nonwovens.

High Throughput and Acceptance Ratio Multipath Routing Algorithm in Cognitive Wireless Mesh Network

The link failure due to the secondary users exiting the licensed channels when primary users reoccupy the licensed channels is very important in cognitive wireless mesh networks (CWMNs). A multipath routing and spectrum allocation algorithm based on channel interference and reusability with Quality of Service (QoS) constraints in CWMNs (MRIR) was proposed. Maximizing the throughput and the acceptance ratio of the wireless service is the objective of the MRIR. First, a primary path of resource conservation with QoS constraints was constructed, then, a resource conservation backup path based on channel interference and reusability with QoS constraints was constructed. The MRIR algorithm contains the primary path routing and spectrum allocation algorithm, and the backup path routing and spectrum allocation algorithm. The simulation results showed that the MRIR algorithm could achieve the expected goals and could achieve a higher throughput and acceptance ratio.

Low-Temperature Steam Annealing of Metal Oxide Thin Films from Aqueous Precursors: Enhanced Counterion Removal, Resistance to Water Absorption, and Dielectric Constant

Aqueous solution deposition has emerged as a potentially scalable, high-throughput route to functional metal oxide thin films. Aqueous routes, however, generally require elevated processing temperatures to produce fully condensed films that are resistant to water absorption. Herein, we report a low-processing-temperature method for preparing more fully condensed, stable metal oxide films from aqueous precursors. We show that a steam anneal at ≤200 °C reduces residual nitrates in zinc oxide, yttrium aluminum oxide, and lanthanum zirconium oxide (LZO) films. An in-depth study on LZO dielectric films reveals steam annealing also reduces residual chloride content, increases resistance to post-anneal water absorption, eliminates void formation, and enhances the dielectric constant. This investigation demonstrates that steam annealing directly affects the decomposition temperatures and chemical evolution of aqueous precursors, suggesting a general means for producing high-quality films at low processing tempera...

Bandwidth-Aware High-Throughput Routing in Multi Hop Wireless Networks with Successive Interference Cancellation

Bandwidth-Aware High-Throughput Routing in Multi Hop Wireless Networks with Successive Interference Cancellation

High-Throughput Network Coding Aware Routing in Time-Varying Multihop Networks

Network coding aware routing (NCAR) has been emerging as an effective approach to create coding opportunities actively in multihop networks. To the best of our knowledge, most of the existing methods focus on a “static” design that considers coding opportunities based on fixed routes and invariable packet flows. This “static” way results in the optimality of routes suffering from a high sensitive behavior on both network topology and flow dynamic and, hence, reduces the throughput of routes in time-varying networks. To solve this problem, we propose a high-throughput NCAR scheme that supports dynamic multihop network connectivity and achieves throughput optimization, even with multiple variable flows. In the proposed scheme, a back-pressure-based NCAR algorithm is designed to push the flows dynamically into the nodes that have better network coding opportunities with no knowledge of network topology and flow dynamic. As a byproduct, the proposed method also exhibits a significantly improved delay performance relative to the traditional back-pressure algorithm. Simulation results reveal that the proposed scheme improves network capacity and alleviates end-to-end delay in heavy load networks.