Internet of Things (IoT) Enabled Smart Indoor Air Quality Monitoring System

This article introduces development of a system that monitors indoor air quality by using Internet of Things (IoT) technology. The objective of this system is to monitor and improve indoor air quality automatically, i.e. with minimum human intervention. The system contains physical circuit and an interactive platform. Main components used in physical circuit are Arduino Leonardo, Dust Sensor, Temperature and Humidity Sensor, LCD Display and Fan. Interactive platforms involved are The Things Network and Ubidots. Principal parameters of interest are sensed by physical circuit and converted into Air Quality Index (AQI), which is then sent to an interactive platform via gateway. After estimating AQI, the Interactive platform triggers events based on certain predetermined conditions to improve air quality through SMS alerts and circuit actuators

Design and characterization of T/R module for commercial beamforming applications

In the smart antenna system, the transmit and receive (T/R) module is one of the core components as it accounts for nearly 45% of the overall smart antenna system cost. Due to the high implementation cost of the T/R module, the literature was mainly centered around the military and satellite radar applications. However, over the years, the cost of the T/R module has been reduced drastically by leveraging on the advanced manufacturing technology, volume production pricing and adaptation of the commercially available off-the-shelf components, as a result, the adoption of the T/R module in commercial and industrial application become possible. In this work, we have proposed a commercially affordable T/R module that operates in 4.9 – 5.9 GHz band for commercial and industrial applications. The T/R module was designed, calibrated, and characterized for use in the beamforming smart antenna system. The design process including the circuit, schematic and printed circuit board (PCB) were highlighted. The proposed recursive calibration process managed to correct the phase error to ± 1° and amplitude error to ± 0.2 dB. In addition, the amplitude distribution of 0.5-1-1-0.5 combination has successfully suppressed the side-lobe level (SLL) to -28.7 dB for 0°, -22.71 dB for ± 20° and -12.77 dB for ± 40° beam steering. This work is aimed to promote the adoption of the T/R module into the commercial and industrial applications such as public or government infrastructure

Correlation analysis of vital signs to monitor disease risks in ubiquitous healthcare system

Healthcare systems for chronic diseases demand continuous monitoring of physiological parameters or vital signs of the patients’ body. Through these vital signs’ information, healthcare experts attempt to diagnose the behavior of a disease. Identifying the relationship between these vital signs is still a big question for the research community. We have proposed a sophisticated way to identify the affiliations between vital signs of three specific diseases i.e., Sepsis, Sleep Apnea, and Intradialytic Hypotension (IDH) through Pearson statistical correlation analysis. Vital signs data of about 32 patients were taken for analysis. Experimental results show significant affiliations of vital signs of Sepsis and IDH with average correlation coefficient of 0.9 and 0.58, respectively. The stability of the mentioned correlation is about 75% and 90%, respectively

Synthesis of 2-{[5-(aralkyl/aryl)-1,3,4-oxadiazol-2- yl]sulfanyl}-N-(4-methyl-1,3-thiazol-2-yl)acetamides: Novel bi-heterocycles as potential therapeutic agents

Purpose: To evaluate the therapeutic potential of new bi-heterocycles  containing a 1,3-thiazole and 1,3,4-oxadiazole in the skeleton against Alzheimer's disease and diabetes, supported by in-silico study. Methods: The synthesis was initiated by the reaction of 4-methyl- 1,3-thiazol-2-amine (1) with bromoacetyl bromide (2) in aqueous basic medium to obtain an electrophile,2-bromo-N-(4-methyl-1,3- thiazol- 2-yl)acetamide (3). In parallel reactions, a series of carboxylic acids, 4a-r, were converted through a sequence of three steps, into respective 1,3,4-oxadiazole heterocyclic cores, 7a-r, to utilize as nucleophiles. Finally, the designed molecules, 8a-r, were synthesized by coupling 7a-r individually with 3 in an aprotic polar solvent. The structures of these bi-heterocycles were elucidated by infrared (IR), electron ionization-mass spectrometry (EI-MS), proton nuclear magnetic resonance (1H-NMR) and carbon nuclear magnetic resonance (13C-NMR). To evaluate their enzyme inhibitory potential, 8a-r were screened against acetylcholinesterase (AChE), but brine shrimp lethality bioassay.Results: The most active compound against AChE was 8l with half-maximal inhibitory concentration (IC50) of 17.25 ± 0.07 μM. Against BChE, the highest inhibitory effect was shown by 8k (56.23 ± 0.09 μM). Compound 8f (161.26 ± 0.23μM) was recognized as a fairly good inhibitor of urease. In view of its inhibition of α-glucosidase, 8o (57.35 ± 0.17μM) was considered a potential therapeutic agent.Conclusion: The results indicate that some of the synthesized products with low toxicity exhibit notable enzyme inhibitory activity against selected enzymes compared with the reference drug, and therefore, are of potential therapeutic interestKeywords: 4-Methyl-1,3-thiazol-2-amine,1,3,4-Oxadiazole,  Cholinesterases, α-Glucosidase, Urease, Brine shrim

A wideband beamforming antenna array for 802.11ac and 4.9 GHz in modern transportation market

In this work, a novel antenna structure has been proposed, which consists of multiple sub-array features i.e., a field selectable beam (90°, 180°, 270°, and 360°) and the choice of gain (11.16, 14.59 and 17.25 dBi) that can be easily adapted to cater for the dynamic scenarios in the transportation environment. The sub-arrays were designed using the microstrip patch antenna (MPA) concept with capacitive feed and dual substrate stacked up configuration for superior operating bandwidth covering the entire 802.11ac (5.17 to 5.85 GHz Industrial Scientific and Medical (ISM) band), in addition to the extended coverage for 4.92 to 4.98 GHz licensed band with narrow azimuth beamwidth of 24°. The sub-array was designed, simulated and experimentally evaluated and the beamforming results revealed that the antenna structure can be integrated with beamforming concepts to provide an enhanced wireless link between the ground base station and the mobile terminals that allows beam steering to focus on the targeted direction and null the interference directions with small beam width. It is expected that the proposed configurable gain/beam beamforming antenna array will further reduce the deployment cost and enhance the anti-interference performance by two-fold, and shall bring the user experience in the transportation market to the next level

Artificial Intelligence enabled Smart Refrigeration Management System using Internet of Things Framework

Design of an intelligent refrigeration management system using artificial intelligence and Internet of Things (IoT) technology is presented in this paper. This system collects the real-time temperature inside the refrigeration implement, record the information of products and enhance function of refrigerators through the application of Internet of Things technology to facilitate people in managing their refrigerated and frozen groceries smartly. The proposed system is divided into two parts, On-board sub-system and Internet based sub-system. An Arduino Leonardo board is used in onboard sub-system to control other components including low power machine vision OpenMV module, temperature & Humidity sensor, and GY-302 light intensity sensor. OpenMV camera module is used for recognizing types of food, reading barcodes and OCR (optical character recognition) through convolution neural network (CNN) algorithm and tesseract-ocr. The food type identification model is trained by the deep learning framework Caffe. GY-302 light intensity sensor works as a switch of camera module. DHT11 sensor is used to monitor the environmental information inside the freezer. The internet based sub-system works on the things network. It saves the information and uploads it from onboard sub-system and works as an interface to food suppliers. The system demonstrates that the combination of existing everyday utility systems and latest Artificial Intelligence (AI) and Internet of Things (IoT) technologies could help develop smarter applications and devices

Efficient blockchain-based group key distribution for secure authentication in VANETs

This paper proposes a group key distribution scheme using smart contract-based blockchain technology. The smart contract’s functions allow for securely distributing the group session key, following the initial legitimacy detection using public key infrastructure-based authentication. For message authentication, we propose a lightweight symmetric key cryptography-based group signature method, supporting the security and privacy requirements of vehicular ad hoc networks (VANETs). Our discussion examined the scheme’s robustness against typical adversarial attacks. To evaluate the gas costs associated with smart contract’s functions, we implemented it on the Ethereum main network. Finally, comprehensive analyses of computation and communication costs demonstrate the scheme’s effectiveness

Inkjet-printed UHF RFID tag based system for salinity and sugar detection

This article presents an RFID system to detect the salinity and sugar contents of water. The proposed system is based on low‐cost ink‐jet printed passive ultrahigh frequency (UHF) RFID tag. The tag is designed using slot match technique, which poses a good imaginary impedance match with RFID chip both in free space and after mounting on the water bottle. Moreover, the tag antenna is exploited as a sensor to detect salt and sugar contents of water by measuring the backscatter power from the tag in term of received signal strength indicator (RSSI). A Tagformance Pro setup form Voyantic is used for measuring RSSI. Furthermore, an approximate relationship is derived between backscatter power and no. of grams of salt and sugar dissolved in water. This study paves a way to check the contents of drinks using portable devices, which is pivotal for healthcare applications in smart cities and the future Internet of things (IoT)

Blockchain-based secret key extraction for efficient and secure authentication in VANETs

Intelligent transportation systems are an emerging technology that facilitates real-time vehicle-to-everything communication. Hence, securing and authenticating data packets for intra- and inter-vehicle communication are fundamental security services in vehicular ad-hoc networks (VANETs). However, public-key cryptography (PKC) is commonly used in signature-based authentication, which consumes significant computation resources and communication bandwidth for signatures generation and verification, and key distribution. Therefore, physical layer-based secret key extraction has emerged as an effective candidate for key agreement, exploiting the randomness and reciprocity features of wireless channels. However, the imperfect channel reciprocity generates discrepancies in the extracted key, and existing reconciliation algorithms suffer from significant communication costs and security issues. In this paper, PKC-based authentication is used for initial legitimacy detection and exchanging authenticated probing packets. Accordingly, we propose a blockchain-based reconciliation technique that allows the trusted third party (TTP) to publish the correction sequence of the mismatched bits through a transaction using a smart contract. The smart contract functions enable the TTP to map the transaction address to vehicle-related information and allow vehicles to obtain the transaction contents securely. The obtained shared key is then used for symmetric key cryptography (SKC)-based authentication for subsequent transmissions, saving significant computation and communication costs. The correctness and security robustness of the scheme are proved using Burrows–Abadi–Needham (BAN)-logic and Automated Validation of Internet Security Protocols and Applications (AVISPA) simulator. We also discussed the scheme’s resistance to typical attacks. The scheme’s performance in terms of packet delay and loss ratio is evaluated using the network simulator (OMNeT++). Finally, the computation analysis shows that the scheme saves ~99% of the time required to verify 1000 messages compared to existing PKC-based schemes