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Recently, Autonomous Ground Vehicles (AGV) and mobile robots have been rapidly developed in various engineering applications, such as Industry 4.0 factory and smart manufacturing. Indoor navigation was one of the most important tasks for the mobile systems as they were often designed to move from one location to another location autonomously without contacting the surrounding objects along the moving path in a usually dynamic and complex indoor environment. There were two key steps to achieve Simultaneous Localization and Mapping (SLAM). First, indoor positioning of the mobile system based on some measurements was done. The second step was to navigate itself inside the indoor map. This was a very challenging problem because there always existed uncertainties in the measurements. It was desired to estimate the positioning errors and determine a safe moving path with high reliability. This paper presented the methodologies for wireless indoor positioning and navigation of AGV with measurement uncertainties. Two kinds of AGV moving trajectories with various design parameters were simulated: a linear trajectory and a curved one. It was found that both greater number of sensors being used for wireless measurements and greater number of measurement trials for multilateration could effectively improve the accuracy of AGV positioning.

Programming logic controllers (PLCs) are vital components for conveyors in production lines, and the sensors and actuators controlled underneath the PLCs represent critical points in the manufacturing process. Attacks targeting the exploitation of PLC vulnerabilities have been on the rise recently. In this study, a PLC test platform aims to analyze the vulnerabilities of a typical industrial setup and perform cyberattack exercises to review the system cybersecurity challenges. The PLC test platform is a sorting machine consisting of an automatic conveyor belt, two Mitsubishi FX5U-32M PLCs, and accessories for material sorting, and Modbus is the selected protocol for data communication. The O.S. on the attacker is Kali ver. 2022.3, runs Nmap and Metasploit to exploit the target Modbus registers. On the other hand, the target host runs the O.S., Ubuntu 22.04 in the cyberattack exercises. The selected attack method for this study is packet reply which can halt operations sending custom data packets to the PLC. In summary, this study provides a basic step-by-step offensive strategy targeting register modification, and the testbed represents a typical industrial environment and its vulnerabilities against cyberattacks with common open-source tools.

Bluetooth Low Energy (BLE) is one of the RF-based technologies that has been utilizing Received Signal Strength Indicators (RSSI) in indoor position location systems (IPS) for decades. Its recent signal stability and propagation distance improvement inspired us to conduct this project. Beacons and scanners used two Bluetooth specifications, BLE 5.0 and 4.2, for experimentations. The measurement paradigm consisted of three segments, RSSI–distance conversion, multi-beacon in-plane, and diverse directional measurement. The analysis methods applied to process the data for precise positioning included the Signal propagation model, Trilateration, Modification coefficient, and Kalman filter. As the experiment results showed, the positioning accuracy could reach 10 cm when the beacons and scanners were at the same horizontal plane in a less-noisy environment. Nevertheless, the positioning accuracy dropped to a meter-scale accuracy when the measurements were executed in a three-dimensional configuration and complex environment. According to the analysis results, the BLE wireless signal strength is susceptible to interference in the manufacturing environment but still workable on certain occasions. In addition, the Bluetooth 5.0 specifications seem more promising in bringing brightness to RTLS applications in the future, due to its higher signal stability and better performance in lower interference environments.

In-Circuit-Test (ICT) is an inevitable process for sustaining the quality of Printed Circuit Boards (PCBs) in the assembly and fabrication process. Applying automation to reduce labor and preventing errors in ICT has been studying by academics and industries for decades. Here we demonstrate a robot centric ICT testing system that integrates the peripheral equipment, also including the shop flow control system (SPCS). The graphic programming software – LabVIEW exploits to integrate robot arm, in-circuit test machine, PLC, HMI, and barcode reader. Communication among the facilities and error handling are the main challenges in the automated ICT system development. Heterogeneous communication protocols and third-party devices with unique syntax have caused some programming difficulties. The challenge of error handling is that it might be on hardware, software, or communication. Moreover, these errors may have occurred at 5-6 different facilities with chain effects. The robot arm dominates the main control sequence from the test start to finish. As a result, a steady automated ICT test system with real-time status monitoring has presented. That assists field personnel in eliminating problems quickly and promotes overall production line operation efficiency.

Sweet potato sporamins are trypsin inhibitors and exhibit strong resistance to digestion by pepsin, trypsin and chymotrypsin. In addition, they constitute the major storage proteins in the sweet potato and, after degradation, provide nitrogen as a nutrient for seedling regrowth in sprouting storage roots. In this report, four cysteine proteases-one asparaginyl endopeptidase (SPAE), two papain-like cysteine proteases (SPCP1 and SPCP2), and one granulin-containing cysteine protease (SPCP3)-were studied to determine their association with sporamin degradation in sprouting storage roots. Sporamin degradation became significant in the flesh of storage roots starting from week 4 after sprouting and this correlated with expression levels of SPAE and SPCP2, but not of SPCP1 and SPCP3. In the outer flesh near the skin, sporamin degradation was more evident and occurred earlier than in the inner flesh of storage roots. Degradation of sporamins in the outer flesh was inversely correlated with the distance of the storage root from the sprout. Exogenous application of SPAE and SPCP2, but not SPCP3, fusion proteins to crude extracts of the outer flesh (i.e., extracted from a depth of 0.3cm and within 2cm of one-week-old sprouts) promoted in vitro sporamin degradation in a dose-dependent manner. Pre-treatment of SPAE and SPCP2 fusion proteins at 95°C for 5min prior to their application to the crude extracts reduced sporamin degradation. These data show that sweet potato asparaginyl endopeptidase SPAE and papain-like cysteine protease SPCP2 participate in sporamin degradation during storage root sprouting.

Soil contamination generated by petroleum hydrocarbons, including benzene, toluene, ethylbenzene and xylene isomers (BTEX), has raised concern around the world. Soil flushing is the process of treating polluted soils with water, surfactants, or solvents, and it is usually feasible for the remediation of petroleumhydrocarbon contaminated soils. Surfactant-enhanced flushing was developed from the conventional pump-and-treat method. A mixture of water and surfactants is often applied to polluted soils and groundwater to improve the solubility of the pollutants during soil flushing. The objective of this study was to investigate the effects of applying anionic surfactants flushing on the treatment of low and high level BTEXcontaminated soils. A surfactant, sodium dodecylsulfate (SDS, anionic type), was used as a washing agent in the column experiments. Column studies were conducted to evaluate the efficiency of BTEX removal from unsaturated porous media using different concentrations of SDS for soil flushing. The soil column [4.2 cm (ID) × 12 cm (L)] was packed with low-level BTEX-contaminated soils (100 and 1,000 mg/kg) and DI water was pumped into the column with a flow rate of 11±1 mL/min. Results from the column study show that BTEX removal efficiencies varied from 63 to 95% when 0.5-2% (v/v) of SDS was pumped through the system. Higher BTEX removal efficiency was obtained when the higher surfactant concentration was applied. The results from this study provide insights into the surfactant washing technology, and will be useful in designing a scaled-up system for field applications.

The objective of this study was to develop a three-stage treatment train system to remediate fuel oil-contaminated soils. The treatment system included the first stage of biodegradable surfactant and groundwater flushing followed by the second stage of Fenton-like oxidation. The third stage was the application of enhanced bioremediation for the removal of residual total petroleum hydrocarbon (TPH) after the first two treatment processes. Three different surfactants [Simple Green™ (SG), Triton X-100, and Tween 80] were evaluated in batch experiments for their feasibility on TPH removal. Results from the surfactant biodegradation and microbial enumeration study indicate that SG was more biodegradable and enhanced the microbial activity of the intrinsic micro-organisms. Thus, SG was applied in the following column experiment. Results from the column study indicate that approximately 80% of TPH in soil (with initial concentration of 50,000 mg kg−1) could be removed after the SG [50 pore volumes (PVs)...

Hsien-Jung Chen1, Guan-Jhong Huang2, Chia-Hung Lin1, Yi-Jing Tsai1, Zhe-Wei Lin1, Shu-Hao Liang1 and Yaw-Huei Lin3 1Department of Biological Sciences, National Sun Yat-sen University, Kaohsiung 2School of Chinese Pharmaceutical Sciences and Chinese Medicine Resources, College of Pharmacy, China Medical University, Taichung 3Institute of Plant and Microbial Biology, Academia Sinica, Nankang, Taipei Taiwan

In this study, batch experiments were conducted to evaluate the feasibility of petroleum-hydrocarbon contaminated soil remediation using persulfate oxidation. Various controlling factors including different persulfate and ferrous ion concentrations, different oxidants (persulfate, hydrogen peroxide, and permanganate), and different contaminants (diesel and fuel oil) were considered. Results show that persulfate oxidation is capable of treating diesel and fuel oil contaminated soil. Higher persulfate and ferrous ion concentrations resulted in higher diesel degrading rates within the applied persulfate/ferrous ion molar ratios. A two-stage diesel degradation was observed in the batch experiments. In addition, treatment of diesel-contaminated soil using in situ metal mineral activation under ambient temperature (e.g., 25 °C) may be a feasible option for site remediation. Results also reveal that persulfate anions could persist in the system for more than five months. Thus, sequential injections of ferrous ion to generate sulfate free radicals might be a feasible way to enhance contaminant oxidation. Diesel oxidation efficiency and rates by the three oxidants followed the sequence of hydrogen peroxide > permanganate > persulfate in the limited timeframes. Results of this study indicate that the application of persulfate oxidation is a feasible method to treat soil contaminated by diesel and fuel oil.

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A planar-structure methanol sensor capable of detecting methanol concentration of 0-2 M was demonstrated. A proton-conducting polymer, recast Nafion 117 perfluorosulfonic acid membrane, was employed as the electrolyte in this work. Thick film technology by screen-printing defined gold layers on an alumina substrate was used for the working and the counter electrodes. A silver/silver chloride electrode was used as the reference electrode. There were inlet holes in the working electrode allowing methanol aqueous solution to move easily through the porous membrane and diffuse onto the electrode surface, where the methanol was decomposed, yielding an oxidation current. Electrochemical impedance spectroscopy and cyclic voltammetry (CV) were used to define the electrochemical characteristics of the sensor. The CV results revealed that the oxidation current had two peaks, illustrating, respectively, the hydrogen desorption at ∼0.22 V SHE and the methanol oxidation at ∼1.0 V SHE (where SHE denotes standard hydrogen electrode). The current output of hydrogen desorption appeared to be reversely proportional to the methanol concentration in 0-2 M.