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Blockchain-based distributed file system security and privacy: A systematic mapping study
No full textBlockchain-based distributed file system is an emerging, decentralized technology that enhances blockchain for storing data and general-purpose files off-chain. The platform integrates blockchain technology with the distributed file system to give users the ability to store data and content respectively on the technology which offers distributed access to data safe and secure among a community of trusted or untrusted networks. This advancement is gaining traction in researchers, with a growing number of research papers and applications being built based on this technology. However, the combination raises doubt on the security and privacy issues of the system. The blockchain-based distributed file system also is still young, unstructured, and in its early stages of research. Thus, a systematic mapping study was carried out and 23 primary studies were identified. Extraction of data is then carried out based on their research type and contribution type facets to gain a wide overview of blockchain and distributed file systems focusing on security and privacy
Mobile IoT cloud-based health monitoring dashboard application for the elderly
No full textOver the years the population are increasing and currently, there are about 8 billion people residing globally. In time, the number of elderly people will increase due to a higher life expectancy over the years. In 1950, the average life cycle is at 46 years and in 2019 the projection expands to 72.6 years. The main reason for this increase is due to better global health services and quality of life. Mobile health technologies are being implemented in most areas related to the healthcare industry to aid elderly patients by monitoring and collecting data related to the diseases and their critical level. This paper described the design and development of an IoT health monitoring system for the elderly. This IoT system consists of two sensing modules, PI and P3. PI measures the body temperature, heart rate, and oxygen saturation (SpO2), while P3 is an accelerometer sensor that detects a fall. Data gathered from these sensors are dispatched wirelessly to the Raspberry Pi gateway and are later stored in a cloud database called InfluxDB. A mobile application is built using the Flutter framework for mobile data visualization purposes. Users can view four screens in the application, including the dashboard for data sensors PI and P3, the profile page, and the notification page. The dashboard displays the elderly data embedded using Grafana. If the patient falls, an alert (OneSignal) in the notification will be sent postfall instantaneously
Raining weather condition observation for FOD detection radar on airport environment
No full textIn this paper, the Triangular Trihedral Corner Reflector (TTCR) that acts as the Foreign Object Debris (FOD) simulator used to observe the FOD detection during rainy weather. The experimental FOD used for this experiment is made of aluminum which gives higher reflectivity. The observation method was to measure the Radar Cross-Section (RCS) in tropical weather conditions in which the FOD simulator is located in between the radar pole and runway 2 at the coordinates (2°43'09.1'N 101°42'40.5'E). This experiment was conducted on actual busy traffic run at Kuala Lumpur International Airport (KLIA) airport. Furthermore, the radar detection system used the Frequency Modulated Continuous Wave (FMCW) operating at 93.1 GHz frequency
Simulated annealing approach for optimal batching in a warehouse
No full textOrder-picking in a warehouse is normally the most expensive operation as it takes the longest time. In conjunction with this, order batching is introduced to expedite the orders for the picking process. An optimized batching order is one of the methods to minimize the traveling path, which eventually reduces operation costs in a warehouse. This problem is known as the NP-hard problem (Nondeterministic Polynomial time), typically solved using metaheuristic approaches. One of the metaheuristic approaches is called Simulated Annealing (SA). The main purpose of this study is to propose a SA algorithm for solving this problem to optimize order batching so that it can minimize the total travel distance in a warehouse. Under the precedence of a randomly defined list of orders and a fixed warehouse layout, a simulation was done to investigate the performance of SA in batching solutions. This is done by using different sample sizes and evaluating the SA algorithm's performance to batch orders compared to other existing batching methods. This research work found that SA method performs better than other existing batching methods such as Sort batching and First-Come First-Served (FCFS). From the results obtained, SA found the shortest distance for all different sample sizes compared to other existing batching methods, that is, by reducing the total distance by 64.27% and 15.46%, respectively, for FCFS method and Sort batching method. This proves that SA is efficient in reducing the total distance, and future implications of this method may be applied in advanced warehouse technology that uses drones or other robots
Image reconstruction of upper limb bone fractures using electrical impedance tomography on python framework
Get PDFvital:149039, valet-20221106-143426
Description
Minor bone fractures could occur due to traumatic incidents such as injuries, vehicle accidents, and falls. The commonly used devices to diagnose for bone fracture are X-ray, Computerized Tomography (CT)-Scan, Positron Emission Tomography (PET)-Scan, and Magnetic Resonance Imaging (MRI). For a series of post diagnosis of bone fracture, it can be health threatening to expose the patient to ionization radiation repeatedly. This research proposes to utilize Electrical Impedance Tomography (EIT) as an invasive modality to monitor the recovery of bone fracture. The aim is to develop EIT circuit to measure the electrical impedance on the phantom model of the upper limb with fractured bones using saline solution and 3D printed bones, the phantom model is reconstructed in 2D images on each cross-section layer using pyEIT and analyze the performance of the reconstructed model of fractured bone. This initiative begins with the development of the EIT circuit system, which consist of sinusoidal waveform generator 100 kHz to 10 MHz frequency range, 32-channel multiplexer unit, instrumentation amplifier with slew rate 35 V/µs, bandpass filter range of frequency from 10 kHz to 4 MHz, Root Mean Square (RMS) to Direct Current (DC) converter, 24-bit analog-to-digital converter, flexible Printed Circuit Board (PCB) 32 electrodes per layer, power supply and microcontroller. The EIT circuit is used to acquire voltage measurement using neighboring and opposite data collection techniques from the phantom tank which consist of saline solution (0.9% NaCl) and was tested on 3D printed Acrylonitrile Butadiene Styrene (ABS) bone and lamb bone. The EIT image of the phantom was reconstructed using pyEIT in three-layers slices on 3D plane. Then, the images were analyzed its performance using root mean square error (RMSE) and correlation coefficient. The RMSE value of the reconstructed images at the frequency of 400 kHz was 0.2785 ± 0.01. From the correlation coefficient between the ABS bone and lamb bone, there are significant similarity in terms of impedance between both materials with Pearson correlation with minimum values of 0.636. It would be beneficial to use the ABS material to simulate the different shape of bone fracture to be reconstructed in EIT system. The fractures are observable on several images. In addition, the depth of the bone is can also be distinguished
Stochastic optimisation model of oil refinery industry and uncertainty quantification in scenario tree of pricing and demand
Get PDFUncertainties in oil prices and product demands affect oil refinery industry profits. The fluctuations in oil prices and unstable product demands result in disruptions at procurement, production, and inventory stages. This issue has increased awareness among managers and decision-makers to include uncertainty characteristics in refinery planning. Stochastic programming is an approach to optimising the profit of oil refineries under uncertainty. A crucial assumption for this approach is the use of scenario trees to characterise the probability distribution of the underlying stochastic process. However, there are limited studies on accurate forecast methods to generate scenario trees with low error. The existing stochastic programming approaches do not include uncertainty quantification of stochastic parameters with an accurate forecast model. Thus, this study has developed a framework to formulate uncertainty quantification of stochastic parameters in a stochastic programming model. In modelling oil price dynamics, information on whether the structural break exists is crucial due to the long memory property that might be camouflaged by the existence of the structural break. In this study, oil prices are modelled and forecasted based on the hurst value, and stochastic differential equations are explored to analyse the uncertainty of the time series. Meanwhile, the Holt-Winter method is adopted to describe the uncertainties of petroleum product demand with seasonal variation. The long memory analysis for the before-break and after-break series did not present similar results, which confirmed that the returns of oil prices did not possess true long memory during this period. The results indicate that Geometric Brownian Motion (GBM) and mean-reverting Ornstein-Uhlenbeck (OU) are accurate forecast models to represent future oil prices. It is found that the Holt-Winter seasonal method is an accurate model to represent future petroleum products demand as its mean absolute percentage error (MAPE) value is less than 10. The study obtained 64 scenarios for oil price uncertainty and 32 scenarios for product demand uncertainty as an effective scenario tree for the input of stochastic programming. This newly developed stochastic programming with uncertainty quantification gained 9% more profit than the stochastic programming based on expert judgment, amounting to approximately USD 269,000 per day (~USD 98 million per year). Thus by incorporating uncertainty quantification of stochastic parameters in stochastic programming, more profit could be gained compared to that using stochastic programming based on an expert judgement approach. This new method would also be able to capture more information in managing the supply and demand of petroleum products. The optimal process flow rate in the oil refinery and the amount of shortfall and surplus petroleum finish products in every possible scenario could be determined so the management could plan for future events. Future work for this study could apply more general techniques and reasonable estimates for the distribution of stochastic parameters. Matching the first four statistical moments such as mean, variance, skewness, and kurtosis that are sufficient to explain the characteristics of the uncertain parameters could also be considered
Structural and optical correlation of europium and dysprosium co-doped boro-telluro-dolomite glasses incorporated with silver nanoparticles
Get PDFRare earth ions doped glasses with tailored lasing and light emitting potency are active area of materials science research. In this view, a series of Eu3+ and of Dy3+ co-doped (at various concentrations) boro-telluro-dolomite (BTD) glasses included with silver nanoparticles (Ag NPs) were prepared by melt-quenching method and characterized for the first time. The role of co-dopants and Ag NPs contents on the optical and structural performance of the studied glasses was evaluated. X-Ray diffraction (XRD) patterns of the as-quenched samples affirmed their amorphous nature, and the energy dispersive X-ray (EDX) spectra showed the presence of actual chemical compositions of the glasses. The existence of Ag NPs with an average diameter of 25.50 nm in the glass matrix was verified using the high-resolution transmission electron microscopy (HRTEM) analyses. Ultrasonic and Vicker‘s micro-hardness analyses displayed high mechanical stability of these glasses. Fourier transformed infrared (FTIR) and Raman spectra of the glasses revealed various chemical functional units in their network structure. Ultraviolet-visible-near-infrared (UV-Vis-NIR) spectral data was used to estimate the optical band gap energies and refractive indices of the glasses using three different models. BTD1.0AgCl sample exhibited a distinct broad surface plasmon resonance (SPR) band at 479 nm. The photoluminescence spectra of the Eu3+-doped glasses (under 464 nm excitation) displayed five significant emission bands at 577, 591, 611, 652 and 702 nm matching with 5D0 7FJ transitions (with J 0, 1, 2, 3, and 4) wherein the band intensities were quenched beyond 1 mol% of Eu3+ doping. The symmetry of the ligands in the vicinity of Eu3+ and Dy3+ in addition to their bonding nature of the glasses were evaluated from the Judd-Ofelt intensity parameters Ω2, Ω4, and Ω6. The observed emission spectral overlap and change in the fluorescence lifetime indicated a substantial bi-directional energy transfer between Eu3+ and Dy3+ in the glass matrix, confirming the Forster-Dexter energy transfer process via the electric dipole–dipole interactions. Besides, the inclusion of Dy3+ altered the emission color of Eu3+ from red region with CIE coordinates of (0.638, 0.361, for BTD1.0Eu glass) to white light zone with CIE coordinates of (0.395, 0.317). The achieved hue was very close to the ideal red color phosphor value of (0.67, 0.33) and pure white light value of (0.33, 0.33). The calculated lasing parameters such as the transition probability, stimulated emission cross-section, luminescence branching ratio, optical gain, gain bandwidth, and radiative lifetime showed enhancement due to the incorporation of Dy3+ and Ag NPs. The produced glasses exhibited high color purity (ranged from 24 – 97.04%) and better quantum efficiency (ranged from 54.88 – 97.81%), wherein such improvements were mainly attributed to the efficient energy transfer between Eu3+ and Dy3+ as well as the Ag NPs SPR-induced local field effects. Overall, a correlation between the structural and optical features of the BTD glasses was determined. Based on the obtained results it can be concluded that the proposed glasses have great potential for the solid-state red laser and white light emitting devices applications
Improving productivity and reducing the sedentary behaviour of educators in Potensi Jaya Tuition Centre
No full textDue to online learning, the new teaching way influenced the working behavior of educators during the class. Tutors must sit for a long hour to teach in front of the screen, it had brought a negative impact on their body’s health and reduced work productivity. The purpose of the study was to improve productivity and reduce the sedentary behavior of educators in Potensi Jaya Tuition Centre, Kulai, Johor. This study looks through the way how to ensure the educators were able to adopt the forces changes from physical learning to online learning and sustain their productivity along with their career. The interventions had been taken which were dynamic workplaces design and IT facilities improvement. Throughout the result findings, the incorporation of 1st and 2nd intervention was achieving 0.49 productivity of teaching material progress out of 0.5 initial objectives had been targeted. Finally, this study was directly decreasing the current and foreseeable issues such as slow down the student learning progress, poor reputation of a tuition center, and high volume of customer complaints. Last but not least, this significant of research had been proven to minimize the low productivity and reduce the sedentary behavior of educators
The effect of dilution oil in the torque performance of magnetorheological grease
Get PDFMagnetorheological (MR) brake is a device that uses MR material to produce braking torque according to induced current. Even though MR Fluid (MRF) is widely used in MR brake as it has high response and is easy to fabricate, the sedimentation issue has degraded the performance of M R brake. Therefore, MR grease (MRG) is introduced to overcome the drawbacks of MRF. Another important benefit of MRG is its self-sealing property which can solve the leaking problem in MRF. Despite the advantageous of no sedimentation of MRG, high viscosity of MRG lower the MR response to the current induced. Thus, the high viscosity of MRG can be reduced by adding dilution oil. Furthermore, the effect of the oil in diluted MRG in MR brake has not been investigated. Several samples of MRGs with different types of dilution oil were prepared by mixing grease and spherical carbonyl iron particles (CIP) using mechanical stirrers. The rheological properties in rotational mode were tested by using rheometer meanwhile the torque performance of MRGs in MR brake were evaluated by changing the current of 0A, 0.4A, 0.8A and 1.2A and fixed the angular speed. The result shows that MRG 3 has the lowest viscosity which is almost 93% reduction while the reduction of viscosity of MRG 2 was 25%. Yet, the torque performances generated by MRG 3 was the highest, 1.44 Nm, followed by MRG 2 and MRG 1. This phenomenon indicated that the improvement of torque performance was dependent on the viscosity of MRGs without the occurrence of sedimentation. Thus, the use of MRG with dilution oil as a substitution of MRF could reduce the sedimentation in MR device and improve the torque performance of MRGs in MR brake
Building information modeling and internet of things integration in the construction industry: A scoping study
Get PDFBuilding Information Modeling (BIM) has emerged as a prospective technology used to advance the practices of construction projects. Also, Internet of Things (IoT), as a technology that connects sensing devices to share information across platforms, has become essential in building and construction environment. The integration of BIM-IoT in the construction industry, a high-risk industry, might increase overall performance and reduce related hazards. However, there is a dearth of studies on the integration of BIM and IoT in the construction industry. Scoping review of literature was performed using various databases such as IEEE Xplore, Science Direct, ACM, Emerald Insight, and Taylors & Francis databases to explore the study demographics, research direction, category, adoption, and performance of the BIM-IoT integration for the construction industry. Out of 2270 articles identified, a total of 81 key and vital articles were found and collected in scoping review to formulate the research questions. The study results revealed that the literature related to BIM-IoT integration and adoption is moderately steady, with constant output in the last four years. Twelve of the contributions were identified, and five were identified to be proposed more and conducted by researchers: investigation, evaluation, model, framework, and system. Also, fifteen (18.51%) studies were identified from the selected works that were evaluated using performance measurement. The findings shed light on some of the most significant difficulties in research related to BIM-IoT integration in the construction industries as well as potential future initiatives