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The biggest limitation of wireless sensor networks is the limited energy of nodes.In order to balance the network load and prolong the network life cycle, this paper proposes a clustering routing protocol based on LEACH-GAF algorithm. This algorithm is optimized based on the classical LEACH and GAF algorithms. Firstly, this paper makes reasonable assumptions about the network model to be established, and establishes a mathematical model for the energy consumption loss of each node in the network. Secondly, the classic LEACH and GAF algorithms are analyzed to pave the way for the following simulation of LEACH-GAF algorithm. Next, the idea of LEACH-GAF algorithm is expounded,GAF algorithm is applied to divide all nodes into regions at the beginning of each round, and then LEACH algorithm is applied to randomly select cluster heads with equal probability in each region, and then the algorithm flow continues according to the classic LEACH algorithm. Finally, the LEACH algorithm and LEACH-GAF algorithm are simulated by MATLAB, and the iteration rounds of the first dead node, the overall span of node death and average residual energy consumption of all nodes are compared between the two algorithms. It is found that the network model using LEACH-GAF algorithm has longer life cycle and better energy consumption balance than the model network using LEACH algorithm.

With the emergence of industry 4.0 and Internet of things (IOT), more and more practical requirements need seamless connection from the smallest sensor to enterprise level systems and other systems with simple, convenient, reliable and economic approach. LoRa is a low-power wide area network (LPWAN) solution specifically designed for IoT devices that send and receive small amounts of data over a range of many kilometers with minimal power consumption. At the system architecture level, Lora is considered as a physical layer technology based on OSI model, mainly based on Chirp spread-spectrum(CSS) technology. LoRa is resulted in a robust and reliable technology compared to other standardized wireless solutions such as Zigbee, Bluetooth, WiFi, and 3G/4G cellular. In this paper, we have designed a single-channel LoRa gateway for Industrial IoT cloud applications using inexpensive single-board computer naming Raspberry Pi plus a LoRa add-on board with the necessary integrated circuits for wireless data communication. The system adopting the LoRa LPWAN technology consists of end devices, gateways, and cloud IoT services. The proposal gateway sends and receives LoRa messages to and from end devices and communicates with upstream cloud application servers through HTTP RESTful protocol and IoT-standard MQTT protocol, according to different data types and specific functional requirements. Unlike other ready-to-use LoRa gateways available on the market in which these gateways simply pass all the original LoRa packets back and forth between and network server over the air called "packet forwarding" mode, the proposal gateway contains smart-agent managing connectivity to devices, coordinating polling mechanism, decoding the packets, passing periodically the unified data to the public or private cloud service applications. Aside based on the embedded web server, the configuration of the gateway is carried out through the web page with desktop or mobile application and it can be updated anytime& anywhere when necessary. The proposal gateway is built cloud ready and can easily integrate with existing networks and enables low-cost, long range communication capability for a multitude of industry applications with minimum effort.

In the development and design process of automobile electronic control unit, the bus simulation test tool CANoe, developed by Vector can monitor and simulate the electronic control unit in real time, which brings convenience to the development of electronic control system and bus system. In this paper, the CANoe simulation software is used to test the integrated body control system of a certain vehicle, and the CANoe electronic unit diagnostic test case is written according to the UDS diagnostic service, so as to realize the functions of automatic fault simulation, fault diagnosis and test result analysis. Shorten the development cycle of the product, reduce the cost of product development and manufacture, and improve the quality of the product.

Identifying tyre pressure or temperature deviations is vital to ensuring the safety and longevity of a fleet’s tyres. The benefits of installing the tyre pressure monitoring system (TPMS) are available both at the new product development process of vehicle factory as well as the product upgrading for aftermarket solution. In this paper, we have proposed a system that offers our users real-time information about the state of their fleet vehicle tyres, including pressure, temperature, overall wear and these records for subsequent analysis. Unlike other TPMS solutions that only locally report real-time tire data such as pressure and temperature information to the driver of the vehicle, whenever any problems in the tyres such as pressure & temperature outside pre-configured limits, our proposed system sends data back to a cloud server for processing and analysis. With an unlimited number of users and 24/7 access, this HTTP web-based software gives back office management unmatched visibility through some RESTful APIs by using desktop or mobile application. The target of proposed system is allowing fleet managers to further improve fleet management requirements, optimal fuel consumption and reduced breakdowns. This system is suitable for all kinds of vehicle fleet including trailers, bus, trucks and any other Heavy-duty vehicles.

The Industrial Internet of Things (IIoT) concentrates on the interconnection and utilization of big and powerful data in manufacturing environments. Data from different devices and different protocols needs to be converted for making these devices IIoT-ready. Today a large number of serial Modbus-based devices still exist in industrial applications. MODBUS RTU is the most widely used industrial protocol for connecting industrial devices and almost all major industrial instrumentation and automation equipment vendors continue to support it in new products. Modbus protocol follows a master– slave model. MQTT is a messaging protocol suitable for the Internet of things (IoT). The MQTT protocol is based on the principles of publishing messages and subscribing to topics commonly known as the publish / subscribe model. In this paper, we have designed a Modbus to MQTT gateway for Industrial IoT cloud applications using inexpensive Raspberry Pi single-board computer and a RS485 add-on board with the necessary integrated circuits for data communication. It supports two-way communication between field devices and cloud applications, and supplies a Modbus RTU interface on RS485 to communicate with on-site field devices. It contains smart-agent at the gateway side to process and convert data sent from the field level of different data formats into the IoT-standard MQTT protocol and pass periodically the unified data to the public or private cloud service applications (Amazon AWS, Alibaba Cloud, or MQTT Broker etc.) for future analyses. Based on embedded web server, the configuration of the gateway is performed through web pages, and updates can be performed over the air when necessary. The proposal gateways provide an easy and secure way to build the IIoT applications now and in the future. Moreover, it can be added to a system and take advantage of the IIoT world while the existing operational technology stays in place.

Reason was analyzed that cable monitor wire protection was easy to make incorrect operation and failure action led by the stray interference signals. Full-wave Fourier Algorithm was deduced which was realized by filtering decaying dc component using table lookup. And on this basis, protection principle of time-sharing amplitude ac cable monitor wire with terminal resistance was proposed and proved in detail. Results showed that this method could effectively filter various stray currents, and especially it could absolutely filter interference signals with the same frequency as the additional ac signal. This method greatly improved the reliability and accuracy of the cable monitor wire protection proved by both theoretical analysis and simulation experiment, which had a significance to improve the reliability of underground power supply and reduce the breakdown.

Carbon nanotubes (CNTs) have been synthesized on porous silicon (PS) substrates by catalytic pyrolysis of acetylene at 823, 873 and 973 K, respectively. Scanning electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, and Field emission measurements have been used to characterize the structures, compositions and electron emission properties of the CNTs, respectively. The results reveal that the diameters of CNTs increase with the growth temperatures as well as the intensities of D and G peaks in Raman spectra. Besides, the carbon content increases as increasing the temperature, whereas the concentrations of oxygen and silicon decrease. Field emission properties for CNTs grown at various temperatures follow exponential increase with the increase of electric field.