Electrochemical Deposition of Lead for Water Quality Sensing

Lead contamination in drinking water can pose serious health risks to humans, and can often go undetected as a result of corrosion of lead infrastructure installed in buildings constructed prior to 1986. Thus, there is an unmet need for timely, cost-effective, and onsite monitoring of lead in drinking water. Here, we have designed a four-electrode system to reliably respond to electrodeposited lead oxide that provides a near real-time indication of lead presence. To better understand this detection mechanism, we investigated the temporal and spatial electrochemical deposition of lead using potential response data, scanning electron microscopy (SEM), fractal dimension (fD), and COMSOL Multiphysics® finite element analysis. Our results suggest that the deposition of lead oxide on the sensor is diffusion limited. Such fundamental understanding of the detection mechanism is critical to improve and shorten the detection time of the sensor. We used this information to improve the detection time and reliability of the signal by reducing the electrode gap distance and agitating the solution. This study provides a path for further optimization of a continuous electrochemical sensor for onsite monitoring of lead in drinking water.

Stress-Aware Periodic Test of Interconnects

Safety-critical systems have to follow extremely high dependability requirements as specified in the standards for automotive, air, and space applications. The required high fault coverage at runtime is usually obtained by a combination of concurrent error detection or correction and periodic tests within rather short time intervals. The concurrent scheme ensures the integrity of computed results while the periodic test has to identify potential aging problems and to prevent any fault accumulation which may invalidate the concurrent error detection mechanism. Such periodic built-in self-test (BIST) schemes are already commercialized for memories and for random logic. The paper at hand extends this approach to interconnect structures. A BIST scheme is presented which targets interconnect defects before they will actually affect the system functionality at nominal speed. A BIST schedule is developed which significantly reduces aging caused by electromigration during the lifetime application of the periodic test.

Colorimetric Measurement of Deltamethrin Pesticide Using a Paper Sensor Based on Aggregation of Gold Nanoparticles

Deltamethrin (DEL) is one of the most commonly used pyrethroid pesticides that can cause serious harms to the ecological environment and human health. Herein, we have developed a paper-based colorimetric sensor impregnated with gold nanoparticles (AuNPs) for on-site determination of DEL pesticide. AuNPs show obvious color change on paper device with the presence of DEL. Measuring the gray intensity of the AuNPs on the reaction zone of the paper sensor allows accurate quantitative analysis. The detection mechanism of DEL on paper sensor was confirmed by UV-Vis spectrophotometry (UV-Vis), Fourier transform infrared spectroscopy (FT-IR), and transmission electron microscope (TEM). Under optimal conditions, the colorimetric sensor exhibited high sensitivity, rapid detection, and low detection limit within the values stipulated by Chinese detection standards (LOD = 0.584 mg/L). Besides, detecting DEL in vegetable and fruit samples also gave satisfying results, which were much consistent with those obtained by spectrophotometry. Overall, this work provided a user-friendly, cost-effective and visualized detection platform, which could be applied to rapidly detect DEL pesticides in the food safety field.

Performance Metric Analysis for a Jamming Detection Mechanism under Collaborative and Cooperative Schemes in Industrial Wireless Sensor Networks

The emergence of Industry 4.0 technologies, such as the Internet of Things (IoT) and Wireless Sensor Networks (WSN), has prompted a reconsideration of methodologies for network security as well as reducing operation and maintenance costs, especially at the physical layer, where the energy consumption plays an important role. This article demonstrates through simulations and experiments that, while the cooperative scheme is more efficient when a WSN is at normal operating conditions, the collaborative scheme offers more enhanced protection against the aggressiveness of jamming in the performance metrics, thus making it safer, reducing operation and maintenance costs and laying the foundations for jamming mitigation. This document additionally offers an algorithm to detect jamming in real time. Firstly, it examines the characteristics and damages caused by the type of aggressor. Secondly, it reflects on the natural immunity of the WSN (which depends on its node density and a cooperative or collaborative configuration). Finally, it considers the performance metrics, especially those that impact energy consumption during transmission.

Social Media Network Attacks and their Preventive Mechanisms: A Review

We live in a virtual world where actual lifestyles are replicated. The growing reliance on the use of social media networks worldwide has resulted in great concern for information security. One of the factors popularizing the social media platforms is how they connect people worldwide to interact, share content, and engage in mutual interactions of common interest that cut across geographical boundaries. Behind all these incredible gains are digital crime equivalence that threatens the physical socialization. Criminal minded elements and hackers are exploiting social media platforms (SMP) for many nefarious activities to harm others. As detection tools are developed to control these crimes so also hackers’ tactics and techniques are constantly evolving. Hackers are constantly developing new attacking tools and hacking strategies to gain malicious access to systems and attack social media network thereby making it difficult for security administrators and organizations to develop and implement the proper policies and procedures necessary to prevent the hackers’ attacks. The increase in cyber-attacks on the social media platforms calls for urgent and more intelligent security measures to enhance the effectiveness of social media platforms. This paper explores the mode and tactics of hackers’ mode of attacks on social media and ways of preventing their activities against users to ensure secure social cyberspace and enhance virtual socialization. Social media platforms are briefly categorized, the various types of attacks are also highlighted with current state-of-the-art preventive mechanisms to overcome the attacks as proposed in research works, finally, social media intrusion detection mechanism is suggested as a second line of defense to combat cybercrime on social media networks.

The Mechanism of Orientation Detection Based on Artificial Visual System

As an important part of the nervous system, the human visual system can provide visual perception for humans. The research on it is of great significance to improve our understanding of biological vision and the human brain. Orientation detection, in which visual cortex neurons respond only to linear stimuli in specific orientations, is an important driving force in computer vision and biological vision. However, the principle of orientation detection is still unknown. This paper proposes an orientation detection mechanism based on dendrite calculation of local orientation detection neurons. We hypothesized the existence of orientation detection neurons that only respond to specific orientations and designed eight neurons that can detect local orientation information. These neurons interact with each other based on the nonlinearity of dendrite generation. Then, local orientation detection neurons are used to extract local orientation information, and global orientation information is deduced from local orientation information. The effectiveness of the mechanism is verified by computer simulation, which shows that the machine can perform orientation detection well in all experiments, regardless of the size, shape, and position of objects. This is consistent with most known physiological experiments.

Intelligent Robotic Palletizer System

In the global wave of automation, logistics and manufacturing are indispensable and important industries. Among them, the related automatic warehousing system is even more urgently needed. There are quite a few cases of using robotic arms in the current industry cargo stacking operations. Traditional operations require engineers to plan the stacking path for the robotic arm. If the size of the object changes, it will take extra time to re-plan the work path. Therefore, in recent years, quite a lot of automatic palletizing software has been developed; however, none of it has a detection mechanism for stacking correctness and personnel safety. As a result, in this research, an intelligent robotic palletizer system is developed based on a self-developed symmetrical algorithm to stack the goods in a staggered arrangement to ensure the overall structure. Innovatively, it is proposed to check the arrangement status and warnings during the visual stack inspection to ensure the correctness of the stacking process. Besides, an AI algorithm is imported to ensure that personnel cannot enter the set dangerous area during the work of the robotic arm to improve safety during stacking. In addition to uploading the relevant data to the cloud database in real time, the stacking process combined database and vision system also provide users with real-time monitoring of system information.

Semiconductor Nanowire Field-Effect Transistors as Sensitive Detectors in the Far-Infrared

Engineering detection dynamics in nanoscale receivers that operate in the far infrared (frequencies in the range 0.1–10 THz) is a challenging task that, however, can open intriguing perspectives for targeted applications in quantum science, biomedicine, space science, tomography, security, process and quality control. Here, we exploited InAs nanowires (NWs) to engineer antenna-coupled THz photodetectors that operated as efficient bolometers or photo thermoelectric receivers at room temperature. We controlled the core detection mechanism by design, through the different architectures of an on-chip resonant antenna, or dynamically, by varying the NW carrier density through electrostatic gating. Noise equivalent powers as low as 670 pWHz−1/2 with 1 µs response time at 2.8 THz were reached.