Search

Airtime fairness has emerged as a key approach to enhancing wireless throughput performance. However, existing research often overlooks the precise calculation of airtime, particularly in relation to TCP acknowledgments. This paper introduces a novel method, implemented on the access point side, for accurately calculating the airtime of TCP and UDP flows. Building on this, we propose a QoS-based scheduling algorithm designed to improve fairness between upload and download traffic. The effectiveness of the algorithm is validated through experiments that accurately measure both throughput and airtime for upload and download traffic. [ABSTRACT FROM AUTHOR]

Vehicle pose detection plays a vital role in modern automotive technology, which can improve driving safety, enhance vehicle stability and provide important support for the development of autonomous driving technology. The current pose estimation methods have the problems of accumulation errors, large algorithm computing power, and expensive cost, so they cannot be widely used in intelligent connected vehicles. This paper proposes a vehicle pose detection method based on an RSU (Roadside Unit). First, the on-board GPS performs the positioning of the target vehicle and transmits the positioning information to the RSU through the UDP (User Data Protocol). Next, the RSU transmits a forward command to the OBU (On-board Unit) through the UDP. The OBU sends the command to the ECU (Electronic Control Unit) to control the vehicle forward. Then, the RSU detects and tracks the vehicle. The RSU takes pictures of two images before and after the movement and obtains the coordinates of the four angle points and the center point by image processing. The vehicle heading direction is determined by the moving direction of the center point of the front and rear two images. Finally, the RSU captures the vehicle images in real time, performs the process of tracking, rectangular fitting and pose calculation to obtain the pose information and transmits the information to the OBU to complete the whole process of vehicle pose detection and information transmission. Experiments show that the method can realize accurate and efficient detection of vehicle pose, meet the real-time requirements of vehicle pose detection, and can be widely used in intelligent vehicles. [ABSTRACT FROM AUTHOR]

[Introduction] Plasma disruption poses a significant threat to the tokamak nuclear device during its running and can cause damage to the device. Such damage can be reduced by adopting the disruption mitigation system, which has an action time highly dependent on the real-time running plasma disruption prediction system for predicting the plasma disruption moment. The deep-learning-based neural network has been used to train plasma disruption prediction models, and the real-time running of the deep-learning-based disruption prediction models requires a huge amount of real-time data from multiple diagnostics. [Method] The article proposed a design scheme for a real-time data acquisition system. The real-time data acquisition and transmission system was designed based on the modular structure and divided into the multiple channels acquisition module, ADC converting control and data reading module, data grouping and packing module and data transmission network module. The data transmission network module was developed on the hardware UDP network stack running on the FPGA at a speed of 10 G. This hardware UDP network stack featured a deterministic data transmission process, enabling a very low transmission latency of the system. [Result] The real-time data acquisition system has a sampling rate reaching 2 MSa/s, a data throughput rate exceeding 9.3 Gb/s, and a data transmission latency of less than 10 μs. [Conclusion] This data acquisition system facilitates the fast transmission of diagnostic data streams to disruption prediction models. The high sampling rates enable the system to perform real-time transmission of one-dimensional diagnostics such as radiation and electron temperature, improving the temporal resolution of data. The high data throughput rate can increase the transmission volume of diagnostic data, and the low data transmission latency can reduce the time required for disruption prediction models to obtain diagnostics data.

The common approach in secure communication channel protocols is to rely on ciphertexts arriving in-order and to close the connection upon any rogue ciphertext. Cryptographic security models for channels generally reflect such design. This is reasonable when running atop lower-level transport protocols like TCP ensuring in-order delivery, as for example, is the case with TLS or SSH. However, protocols like QUIC or DTLS which run over a non-reliable transport such as UDP, do not—and in fact cannot—close the connection if packets are lost or arrive in a different order. Those protocols instead have to carefully catch effects arising naturally in unreliable networks, usually by using a sliding-window technique where ciphertexts can be decrypted correctly as long as they are not misplaced too far. In order to be able to capture QUIC and the newest DTLS version 1.3, we introduce a generalized notion of robustness of cryptographic channels. This property can capture unreliable network behavior and guarantees that adversarial tampering cannot hinder ciphertexts that can be decrypted correctly from being accepted. We show that robustness is orthogonal to the common notion of integrity for channels, but together with integrity and chosen-plaintext security it provides a robust analog of chosen-ciphertext security of channels. In contrast to prior work, robustness allows us to study packet encryption in the record layer protocols of QUIC and of DTLS 1.3 and the novel sliding-window techniques both protocols employ. We show that both protocols achieve robust chosen-ciphertext security based on certain properties of their sliding-window techniques and the underlying AEAD schemes. Notably, the robustness needed in handling unreliable network messages requires both record layer protocols to tolerate repeated adversarial forgery attempts. This means we can only establish non-tight security bounds (in terms of AEAD integrity), a security degradation that was missed in earlier protocol drafts. Our bounds led the responsible IETF working groups to introduce concrete forgery limits for both protocols and the IRTF CFRG to consider AEAD usage limits more broadly. [ABSTRACT FROM AUTHOR]

UDP (User Datagram Protocol) does not adopt retransmission mechanism. Packet loss may happen when poor contact or electromagnetic interference occurs, which can aff ect the link. Quick analysis for a single data file is achieved by using the Wireshark's built-in statistical and ranking functions. Based on the ranking idea, Auto-Array method, which adopts a software algorithm, is further studied. Tests and comparisons show that Auto-Array method can provide quick analysis for multiple data files. Details of the packet loss in UDP data files can also be output. The method can provide criteria for evaluating the reliability of UDP transmission. [ABSTRACT FROM AUTHOR]

One of the most important developments in the energy industry is the evolution of smart grids, which record minute details of voltage levels, energy usage, and other critical electrical variables through General Packet Radio Service (GPRS)-enabled meters. This phenomenon creates an extensive dataset for the optimization of the grid system. However, the minute-by-minute energy details recorded by GPRS meters are challenging to store and manage in physical storage resources (old techniques lead to a memory shortage). This study investigates using the distributed file system, replicated Gluster, as a reliable storage option for handling and protecting the enormous volumes of data produced by smart grid components. This study performs two essential tasks. (1) The storage of virtual data received from GPRS meters and load flow analysis of SynerGee Electric 4.0 software from the smart grid (we have extracted electrical data from 16 outgoing feeders, distributed lines, in this manuscript). (2) Tele-trafficking is performed to check the performance of replicated Gluster (RG) for virtual data (electrical data received from the smart grid) storage in terms of User Datagram Protocol (UDP), Transmission Control Protocol (TCP), data flow, and jitter delays. This storage technique provides more opportuni11ty to analyze and perform smart techniques efficiently for future requirement, analysis, and load estimation in smart grids compared to traditional storage methods. [ABSTRACT FROM AUTHOR]

Copyright of Southern Energy Construction is the property of Southern Energy Construction Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, microwave radiation pulses emitted from natural lightning have been found to interfere with the Fourth Generation Long Term Evolution (4G LTE) mobile communication data transmission. Two sets of measurement instruments have been synchronized where lightning electric field sensor together with 4G LTE network were evaluated its performance under two conditions namely fair-weather (four cases) and storm (four lightning cases). The microwave radiation emitted from lightning was directly measured without the use of a mixer and down-convertor to ensure the preservation of information such as the number of pulses and amplitude. A client-server architecture has been set up for data transmission utilizing User Datagram Protocol (UDP) where the packets have been generated by using Internet Performance Working Group Third Version (Iperf3) platform. Under fair-weather conditions, the 4G LTE connection at both the client and server nodes demonstrated stability and experienced minimal impact. On the other hand, natural lightning electromagnetic interference disrupted the 4G LTE communication links. Among the four reported storms, three storms have affected the 4G LTE data transmission. The first and fourth storms resulted in a complete connection drop to zero, lasting for 4 minutes and 2 seconds and for 44 seconds, respectively. The observation of hundreds microwave radiation pulses, each characterized by individual oscillating features suggests a potential disruption to packet transmission. Moreover, negative could-to-ground (-CG) and intra-cloud (IC) lightning flashes have been identified as the primary sources of interference to the 4G LTE data transmission. This information could be useful for future studies and for developers working on improving the reliability and performance of 4G LTE networks, particularly in areas prone to thunderstorms.

An application-specific integrated circuit (ASIC) bridge for translating and transmitting data between Ethernet and USB was developed in this study. The Ethernet packets of this device are in the IEEE 802.3 standard frame format and transmitted over a 1-Gbit media-independent interface. The device supports the user datagram and address resolution protocols with high transfer speeds. The proposed hardware solution achieves a higher data throughput (682.13 Mbps) than conventional software-based solutions. Its design was validated on a field-programmable gate array (FPGA), and the ASIC was then fabricated using the Taiwan Semiconductor Manufacturing Company 0.18- $\mu $ m CMOS process. The fabricated ASIC’s power consumption, gate count, and chip area were 74.68 mW, 50 100, and $1.199\times 1.196$ mm2, respectively. Moreover, its operating frequency was 125 MHz under a power supply voltage of 1.8 V. The proposed bridge had high throughput and low latency on the FPGA, and the ASIC package was robust, convenient to use, and energy efficient.

Muchas aplicaciones hoy en día utilizan el protocolo de la capa de aplicación denominado HTTP. HTTP/3 es la última versión oficial, fue estandarizado en agosto de 2020, desarrollado como una evolución de HTTP/2 y basado en el protocolo de transporte QUIC. HTTP/3 fue diseñado para mejorar el rendimiento y la eficiencia de las comunicaciones web, especialmente en entornos de red con alta pérdida de paquetes y fluctuaciones de conexión. QUIC es un protocolo de nivel de usuario que se ejecuta sobre UDP para resolver algunas limitaciones y desventajas de TCP en el contexto de las comunicaciones web. Al utilizar UDP, QUIC ofrece ventajas como una menor latencia, mayor eficiencia en redes con alta pérdida de paquetes y la capacidad de establecer conexiones más rápidas. El propósito de este documento es proporcionar una visión general de la propuesta del protocolo QUIC realizada por Google, y un análisis de las evaluaciones realizadas de desempeño de HTTP/3 utilizando QUIC. Por último, se describirá el diseño del protocolo y los mecanismos utilizados: control de flujo, control de congestión, seguridad y multiplexación.

The ever-increasing number of plug-in electric vehicles (PEVs) requires appropriate electric vehicle grid integration (EVGI) for charging coordination to maintain grid stability and enhance PEV user convenience. As such, the widespread adoption of electric mobility can be successful. EVGI is facilitated through charging stations and empowers PEV users to manage their charging demand by using smart charging solutions. This makes PEV grids assets that provide flexibility to the power grid. The Internet of Things (IoT) feature can make smooth EVGI possible through a supporting communication infrastructure. In this regard, the selection of an appropriate communication protocol is essential for the successful implementation of EVGI. This study assesses the efficacy of the UK’s 4G network with TCP and 4G UDP protocols for potential EVGI operations. For this, an EVGI emulation test bed is developed, featuring three charging parking lots with the capacity to accommodate up to 64 PEVs. The network’s performance is assessed in terms of data packet loss (e.g., the data-exchange capability between EVGI entities) and latency metrics. The findings reveal that while 4G TCP often outperforms 4G UDP, both achieve latencies of less than 1 s with confidence intervals of 90% or greater for single PEV cases. However, it is observed that the high penetration of PEVs introduces a pronounced latency due to queuing delays in the network including routers and the base station servers, highlighting the challenges associated with maintaining efficient EVGI coordination, which in turn affects the efficient use of grid assets.

The main goal of cyber-physical power systems (CPPSs) is to provide seamless collaboration between the physical and cyber systems, bridging disciplines, such as communication networks and control systems. Controlling the operation of Microgrids (MGs) as a cyber-physical power system must include both the physical and cyber layers. Generally, the microgrid control center MGCC is employed for reliable operation management between the different local controllers within the networked microgrids (NMGs). Therefore, an excessive number of communication channels between the MGCC and the local controllers will exist, affecting the control performance of the NMGs. This paper focuses on developing an innovative communication network emulation model for standalone DC networked microgrids using a Network Simulator (NS3), miming the communication infrastructure to control the networked microgrid system. Through the real-time simulation, the performance of the proposed communication network model was evaluated by employing two transmission protocols, User Datagram Protocol (UDP) and Transmission Control Protocol (TCP), to facilitate the data exchange between the MGCC and the local controllers in each MG while operating under different traffic loads. The comparative results of using these protocols in terms of the key performance indicators (KPIs) of the communication performance metrics, such as the mean delay, percentage of packet loss, and transmitted and received bitrate, reveal notable insights into their suitability in data transmission for controlling and managing the operation of the NMGs.

Hardware implementations of networked control systems (NCS) are still rarely found in various research publications so that technical issues, such as how to measure random delay and substitute it into the control equation, still need to be studied further. This study is therefore aimed to compare the performance of NCS based on the used protocol in the ethernet network, i.e. user datagram protocol (UDP) or transmission control protocol (TCP), by applying it in room temperature plant. In this study, the controlled plant is influenced by the fan speed, heating, and window position plant. The heating plant is employed as the main control, while the others are set as sub-plants. The three plants use proportional–integral–derivative (PID) controller where they are regulated by fuzzy logic as the master control unit (MCU). The MCU and three PID controllers are located in the master terminal unit (MTU) while the actuators and sensors are located in the three different remote terminal units (RTU). The verification experiment shows that there is no overshoot on TCP-based NCS, while UDP has 0.725%. For the risetime, the response on UDP is faster than TCP (110.22 as compared to 138.18 s). The same thing also happened to the settling time, where the time with UDP was 101.86 s and 128.44 s for TCP.

With the proliferation of mobile devices and various mobile services, ensuring smooth mobility for users has become a major challenge. The future internet is expected to be more mobile-friendly, with advancing technologies that will transform internet management in the coming decades. These technological advancements will help address mobility issues and provide a better internet experience for mobile devices and users. The transport layer plays a crucial role in the internet protocol suite by enabling communication between applications running on different servers. However, the widely used protocols, TCP and UDP, have several limitations, such as unreliability and slow performance due to three-way handshakes. To tackle these issues, Google introduced quick UDP internet connections (QUIC). QUIC aims to enhance latency, delay, and data transmission reliability. Q-MOFI, a future internet architecture focused on mobile devices and based on QUIC, strives to achieve these goals. Moreover, it enhances throughput by implementing multiplexing. Q-MOFI outperforms traditional UDP-based MOFI in terms of throughput gains, minimizing packet loss, and reducing binding operation latency, even when the number of hosts increases. The efficiency of this model has been validated through experimental testing. [ABSTRACT FROM AUTHOR]

Modern heterogeneous packet networks generate network traffic with a complex structure. In this article, the object of study is a time series. The total number of User Datagram Protocol (UDP) packets has reached 250242. According to analysts, the growth trend of traffic, including real-time applications, will continue and the volume of data will grow, which may lead to the formation of packet queues when processed by network devices. In this case, there may be losses in case of long queues. To solve this problem, a power spectrum assessment was carried out. The AR maximum entropy estimator has been shown to be more sensitive than the auxiliary Fourier estimator. Accounting for non-stationarity by spectral methods is possible only through estimation in a sliding time window. Nine diagrams of spectral-temporal analysis of the original series, its increments, and the mixed series of increments were obtained: with default parameters, with small and large windows. Diagrams related to the original series reflect the dynamics of changes in data transmission intensity in the network; they show higher temporal resolution, indicating the presence of high-frequency components (noise) and the presence of low-frequency components (trend). Diagrams with increments describe signals of periodic components; changing the length of the window did not reflect the presence of noise or trend signs. Diagrams with mixed increments show that frequency components are uniformly distributed. The uniqueness of this work lies in the real measured data, and a distinctive feature of the obtained results is the visual examination of the complex traffic structure, allowing for the resolution of the investigated problem. Practical application of the results obtained can be applied in Quality of Service (QoS) management, resource planning, and network performance optimization. [ABSTRACT FROM AUTHOR]

This paper investigates and compares experimental techniques in irrigation systems, focusing on crucial factors such as soil fertility, moisture level, pH level, water availability, and temperature for efficient agriculture and increased food productivity. The proposed method involves transmitting data from sensors (e.g., soil-moisture, pH, temperature, and air moisture) to an IoT platform utilizing LoRa communication protocol, processing it, and utilizing it for developing a fuzzy-control action to determine the optimal irrigation valve opening while also notifying the irrigation water pH. LoRa is a low-power wide area network solution enabling longrange communication with minimal energy consumption. The objective is to create a smart irrigation system for efficient water management in agriculture. The system monitors parameters like soil moisture, ambient temperature, and water pH, utilizing a fuzzy logic controller to regulate irrigation and minimize water wastage. LabVIEW facilitates data processing, valve control, and sensor data acquisition. LoRa is used for data transmission to a data concentrator and then broadcasted to the TTN platform for visualization and analysis. This setup demonstrates the effectiveness of LoRa and the fuzzy logic controller in achieving resourceefficient irrigation practices for sustainable agriculture. [ABSTRACT FROM AUTHOR]

The ever-increasing number of plug-in electric vehicles (PEVs) requires appropriate electric vehicle grid integration (EVGI) for charging coordination to maintain grid stability and enhance PEV user convenience. As such, the widespread adoption of electric mobility can be successful. EVGI is facilitated through charging stations and empowers PEV users to manage their charging demand by using smart charging solutions. This makes PEV grids assets that provide flexibility to the power grid. The Internet of Things (IoT) feature can make smooth EVGI possible through a supporting communication infrastructure. In this regard, the selection of an appropriate communication protocol is essential for the successful implementation of EVGI. This study assesses the efficacy of the UK's 4G network with TCP and 4G UDP protocols for potential EVGI operations. For this, an EVGI emulation test bed is developed, featuring three charging parking lots with the capacity to accommodate up to 64 PEVs. The network's performance is assessed in terms of data packet loss (e.g., the data-exchange capability between EVGI entities) and latency metrics. The findings reveal that while 4G TCP often outperforms 4G UDP, both achieve latencies of less than 1 s with confidence intervals of 90% or greater for single PEV cases. However, it is observed that the high penetration of PEVs introduces a pronounced latency due to queuing delays in the network including routers and the base station servers, highlighting the challenges associated with maintaining efficient EVGI coordination, which in turn affects the efficient use of grid assets. [ABSTRACT FROM AUTHOR]

Copyright of Techno.com is the property of Universitas Dian Nuswantoro, Fakultas Ilmu Komputer and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The results of a study of the architecture of hardware and software for unidirectional data transmission in computer networks are presented. The architecture is presented in the form of optical galvanic isolation, media converters and proxy servers, excluding bidirectional data transmission at the hardware level. Work on unidirectional data transmission is carried out on the basis of the UDP transport protocol, which provides operation without establishing bidirectional interaction. Unidirectional data transfer is carried out by a proxy server running a special sender’s software that performs unidirectional data file transfer. This software converts the source data file into a unidirectional stream of UDP datagrams. To receive a unidirectional stream of UDP datagrams, a proxy server is used, on which the recipient’s special software is running. The receiving proxy server receives, processes and generates the source data file. The reliability of the unidirectional transmission of data files is ensured by redundancy (multiple transmission) and checksum verification.

In this scientific article a comprehensive investigation of the network traffic using the command-line packets sniffer Tcpdump in kali Linux is made. [ABSTRACT FROM AUTHOR]

In this scientific article a basic network penetration testing with the network tool Netcat in Linux-based operating systems is presented. [ABSTRACT FROM AUTHOR]

Port scanning is the first step taken by attackers before an attack is deployed. It is employed to identify the targeted host's IP addresses, network devices and services running which later be used to determine the server locations and diagnose security levels of the victim by revealing the presence of security measures in place such as firewall between the server and the network devices. With different types of port scanning techniques and tools available, the impact on the targeted host's performance will vary. In this research, a comparative study of port scanning techniques is proposed to evaluate their impact on the scanned hosts performance. Three scanning techniques are compared namely TCP SYN, TCP Connect and UDP scan and several experiments have been conducted using NMAP, Unicornscan, Netcat, Apache2 web server and Zabbix running in virtual machine (VM) environment. Of the three port scanning techniques, TCP SYN scan has the least impact on the targeted scanned host with average response time of 0.69ms for a single scan and 0.421ms for 100 scans. [ABSTRACT FROM AUTHOR]

This paper presents the design and development of a control scheme, for a robot master–slave teleoperation system man–machine interface. The developed system consists of JUPITER XL SCARA robot as a slave manipulator with only the first two links activated, a wireless User Datagram Protocol (UDP) network, and PC as a master controller. The system model parameters identified using the Least-Squares method. A workspace-control system was developed to deals with the problem of position-tracking of bilateral teleoperated two degrees of freedom manipulator, and aid the human operator in driving and controlling the slave robot that performs critical and difficult tasks such as underwater works. A Proportional-Integral-Derivative (PID) and Fuzzy Logic Control (FLC) controllers with different input signals were applied to the system. It was proved experimentally and by simulation on Matlab that the FLC gave a better performance than the PID controller. The two parallel loop subroutine technique proved a great enhancement to the system performance as it decreased the total delay time in the system to almost 25 ms.

Several purinergic receptors have been identified on platelets which are involved in hemostatic and thrombotic processes. The aim of the present study was to investigate the effects of uridine and its nucleotides on platelet aggregation and hemostasis in platelet-rich plasma (PRP) and whole blood. The effects of uridine, UMP, UDP, and UTP at different final concentrations (1 to 1000 µM) on platelet aggregation were studied using an aggregometer. In PRP samples, platelet aggregation was induced by ADP, collagen and epinephrine 3 min after addition of uridine, UMP, UDP, UTP and saline (as a control). All thromboelastogram experiments were performed at 1000 µM final concentrations of uridine and its nucleotides in whole blood. UDP and UTP were also tested in thromboelastogram with PRP. Our results showed that UDP, and especially UTP, inhibited ADP- and collagen-induced aggregation in a concentration-dependent manner. In whole blood thromboelastogram experiments, UDP stimulated clot formation while UTP suppressed clot formation. When thromboelastogram experiments were repeated with PRP, UTP's inhibitory effect on platelets was confirmed, while UDP's stimulated clot forming effect disappeared. Collectively, our data showed that UTP inhibited platelet aggregation in a concentration-dependent manner and suppressed clot formation. On the other hand, UDP exhibited distinct effects on whole blood or PRP in thromboelastogram. These data suggest that the difference on effects of UTP and UDP might have arisen from the different receptors that they stimulate and warrant further investigation with regard to their in vivo actions on platelet aggregation and hemostasis. Highlights: UDP and UTP exhibit different effects on platelet aggregation and hemostasis. UTP inhibits platelet aggregation and hemostasis both in whole blood and PRP samples. UDP has distinct effects on hemostasis in whole blood or PRP in thromboelastogram. The findings suggest the involvement of different receptors stimulated by UDP or UTP in the observed effects. [ABSTRACT FROM AUTHOR]

Summary: Ubiquitin‐like domain‐containing proteins (UDPs) are involved in the ubiquitin‐proteasome system because of their ability to interact with the 26S proteasome. Here, we identified potato StUDP as a target of the Phytophthora infestans RXLR effector Pi06432 (PITG_06432), which supresses the salicylic acid (SA)‐related immune pathway.By overexpressing and silencing of StUDP in potato, we show that StUDP negatively regulates plant immunity against P. infestans. StUDP interacts with, and destabilizes, the 26S proteasome subunit that is referred to as REGULATORY PARTICLE TRIPLE‐A ATP‐ASE (RPT) subunit StRPT3b. This destabilization represses the proteasome activity. Proteomic analysis and Western blotting show that StUDP decreases the stability of the master transcription factor SYSTEMIC ACQUIRED RESISTANCE DEFICIENT 1 (SARD1) in SA biosynthesis.StUDP negatively regulates the SA signalling pathway by repressing the proteasome activity and destabilizing StSARD1, leading to a decreased expression of the SARD1‐targeted gene ISOCHORISMATE SYNTHASE 1 and thereby a decrease in SA content. Pi06432 stabilizes StUDP, and it depends on StUDP to destabilize StRPT3b and thereby supress the proteasome activity.Our study reveals that the P. infestans effector Pi06432 targets StUDP to hamper the homeostasis of the proteasome by the degradation of the proteasome subunit StRPT3b and thereby suppresses SA‐related immunity. [ABSTRACT FROM AUTHOR]

Modification of metal melts by mechanochemically activated ultrafine powders (UDP) makes it possible to obtain ferrous and non-ferrous metal alloys with fundamentally new performance properties due to changes in the structure of metal alloys. The purposes of this work were to analyse the efficiency of the process of modifying copper alloys with ultrafine powders and to develop a special device for introducing a modifier into the melt. Experimental studies of the process of modifying melts of aluminum, silicon and tin bronze with mechanochemically activated UDP of natural graphite, as well as silicon and aluminum oxides with a fraction of -100+0 microns in a concentration of 0.2-0.25 % were carried out. It is shown that the modification of bronze melts by the above-mentioned powders affects the microstructure of alloys, intensively grinding it in comparison with the initial structure. It was found that the reduction in the size of the dendritic cell in comparison with the initial alloy reaches 25%, and the micrograin - 230%. Grain grinding leads to an increase in the mechanical properties of copper alloys, such as Brinell hardness HB, tensile strength σb, elongation δ. For more efficient implementation of the process of modifying metal melts with ultrafine powders, an original design of a device for introducing modifiers into the melt has been developed, characterized by simplicity and cost-effectiveness of execution.

Airborne Ad-hoc Networks (AANETs) are becoming highly popular nowadays. Due to the fast movements of aircraft, there are frequent topology updates which result into a link break between two communicating aircraft. The routing overhead increases multiple times in search of a new route continuously. To deal with this issue of increased overhead, this paper presents a new routing scheme named as Airborne-OLSR (AOLSR). The proposed scheme provides more optimization of Multi-point Relay (MPR) selection criteria used in existing Optimized Link State Routing (OLSR) protocol. This decreases the amount of overhead by selecting the MPR either on the right side or the left side of the source node which depends on the location of the node to which data is to be sent. The decrease in overhead will also result into more bandwidth availability which decreases the possibility of link break. The proposed routing scheme has been compared with the existing OLSR protocol for UDP and TCP environment with varying node speed in 3-D Gauss Markov Mobility model using network simulator-3(ns-3). The simulation analysis shows that the proposed scheme is better in terms of packet delivery ratio, End-to-End delay, routing overhead and throughput as compared to OLSR. We have also compared the AOLSR with previously developed AANET specific protocols like automatic dependent surveillance-broadcast system aided geographic routing protocol(A-GR) and geographic routing protocol for aircraft ad hoc network (GRAA).

Network Diagnosis Tools with industrial-grade quality are not widely available for common users such as researchers and students. This kind of tool enables users to develop Distributed Embedded Systems using low-cost and reliable setups. In the context of RISC-V Extensions and Domain-Specific Architecture, this paper proposes a Real-Time RISC-V-based CAN-FD Bus Diagnosis Tool, named RiscDiag CanFd, as an open-source alternative. The RISC-V Core extension is a CAN-FD Communication Unit controlled by a dedicated ISA Extension. Besides the extended RISC-V core, the proposed SoC provides UDP Communication via Ethernet for connecting the proposed solution to a PC. Additionally, a GUI application was developed for accessing and using the hardware solution deployed in an FPGA. The proposed solution is evaluated by measuring the lost frame rate, the precision of captured frames timestamps and the latency of preparing data for Ethernet communication. Measurements revealed a 0% frame loss rate, a timestamp error under 0.001% and an acquisition cycle jitter under 10 ns. [ABSTRACT FROM AUTHOR]