Smart Cities Security Threat Landscape: A Review

There has been a swift rise in the development of smart cities. This evolution has been prompted by the rise in emerging technologies such as edge computing, IoT, data science, and analytics. Combining these technologies has paved the way for new, automated systems for managing and monitoring procedures and industries, resulting in increased efficiency and improved quality of life. While these interconnected services assist in managing the growing population in the urban environments through efficient service delivery and increased operational efficiency, they also increase the risk of adversary threats, security, and privacy challenges to smart cities. This paper presents the holistic view of the security landscape and highlights the security threats, challenges, and risks to the smart city environment

Modelling of abrasive waterjet milled footprints

Abrasive waterjet (AWJ) cutting is one of the most promising fast emerging non-traditional cutting technologies. It is highly competitive for machining difficult-to-cut materials like ceramics, composites and titanium alloys as compared to other nonconventional processes (e.g. laser, EDM) which are either technologically inappropriate or fail to be cost-effective. However, at the moment most of the usage of the AWJ machining lies in the area of the through cutting applications and to perform controlled depth cutting (milling) is still at craftsmanship level. This is due to the facts that: (i) AWJ machining is based on employing a jet plume as a "soft body" tool, the footprint of which not only depends on the jet energy parameters (e.g. pressure, abrasive mass flow rate, etc) but also on the jet kinematic parameters (e.g. jet traverse speed) which make controlling of the jet penetration depth very difficult; (ii) there is absence of the appropriate and reliable models that can simulate and predict the AWJ milled footprints and this is one of the major obstructions constraining the use of the AWJ milling applications. The aim of this thesis is to develop accurate models for predicting the A WJ milled footprints. The workpiece material considered is a titanium based superalloy (Ti-6Al- 4V) which is extensively used in the aerospace and medical industry. Two modelling approaches; finite element (FE) modelling and mathematical modelling are presented in this work. Considerable numbers of experiments are conducted to generate the data for validating the results from the models. The models presented in the current study are closer to the real life conditions occurring during the A WJ machining as compared to the state of the art in modelling of AWJ machining. Regarding the FE modelling, the abrasive particles (i.e. garnet) are modeled as elastic with a tensile failure criterion with various non-spherical shapes (rhombic, triangular and trapezoidal) and sharp cutting edges in contrast to the usual approach of assuming them as rigid spherical particles. The effects of mass flow rate of the abrasive particles, traverse speed of the AWJ plume across the workpiece and Gaussian spatial distribution of the abrasive particles in the jet plume are also incorporated in the FE model. The FE model is developed to an extent that it can simulate the footprints as a result of overlapping passes of the AWJ. The simulated jet footprints from the FE models are in good agreement (maximum errors ≤ 15%) with the experimental results. From the mathematical modelling point of view, a model is developed that can accurately predict the AWJ milled footprints with root-mean-squared errors less than 9%. The model takes into account the effects of jet incidence angles, traverse speeds and arbitrarily-moving jet-paths within the target surface. The model is computationally inexpensive and can be used for real time predictions of footprints during CNC machining. The current study provides the reliable models that can be employed for accurate prediction of the abrasive waterjet milled footprints at various process parameters which is a necessary step towards the exploitation of the A WJ machining for controlled depth cutting applications and its automation

Modelling of abrasive waterjet milled footprints

Abrasive waterjet (AWJ) cutting is one of the most promising fast emerging non-traditional cutting technologies. It is highly competitive for machining difficult-to-cut materials like ceramics, composites and titanium alloys as compared to other nonconventional processes (e.g. laser, EDM) which are either technologically inappropriate or fail to be cost-effective. However, at the moment most of the usage of the AWJ machining lies in the area of the through cutting applications and to perform controlled depth cutting (milling) is still at craftsmanship level. This is due to the facts that: (i) AWJ machining is based on employing a jet plume as a "soft body" tool, the footprint of which not only depends on the jet energy parameters (e.g. pressure, abrasive mass flow rate, etc) but also on the jet kinematic parameters (e.g. jet traverse speed) which make controlling of the jet penetration depth very difficult; (ii) there is absence of the appropriate and reliable models that can simulate and predict the AWJ milled footprints and this is one of the major obstructions constraining the use of the AWJ milling applications. The aim of this thesis is to develop accurate models for predicting the A WJ milled footprints. The workpiece material considered is a titanium based superalloy (Ti-6Al- 4V) which is extensively used in the aerospace and medical industry. Two modelling approaches; finite element (FE) modelling and mathematical modelling are presented in this work. Considerable numbers of experiments are conducted to generate the data for validating the results from the models. The models presented in the current study are closer to the real life conditions occurring during the A WJ machining as compared to the state of the art in modelling of AWJ machining. Regarding the FE modelling, the abrasive particles (i.e. garnet) are modeled as elastic with a tensile failure criterion with various non-spherical shapes (rhombic, triangular and trapezoidal) and sharp cutting edges in contrast to the usual approach of assuming them as rigid spherical particles. The effects of mass flow rate of the abrasive particles, traverse speed of the AWJ plume across the workpiece and Gaussian spatial distribution of the abrasive particles in the jet plume are also incorporated in the FE model. The FE model is developed to an extent that it can simulate the footprints as a result of overlapping passes of the AWJ. The simulated jet footprints from the FE models are in good agreement (maximum errors ≤ 15%) with the experimental results. From the mathematical modelling point of view, a model is developed that can accurately predict the AWJ milled footprints with root-mean-squared errors less than 9%. The model takes into account the effects of jet incidence angles, traverse speeds and arbitrarily-moving jet-paths within the target surface. The model is computationally inexpensive and can be used for real time predictions of footprints during CNC machining. The current study provides the reliable models that can be employed for accurate prediction of the abrasive waterjet milled footprints at various process parameters which is a necessary step towards the exploitation of the A WJ machining for controlled depth cutting applications and its automation

"Development and Validation of an Isocratic Reverse-Phase High-Performance Liquid Chromatographic Method for the Simultaneous Determination of Desloratadine and Montelukast sodium in Bulk Drug, Pharmaceutical Dosage Forms, and Human Plasma.”

This research article presents a straightforward, viable, and sensitive isocratic reverse-phase high-performance liquid chromatographic (RP-HPLC) method for the simultaneous determination of Desloratadine and Montelukast sodium in bulk drug, pharmaceutical dosage forms, and human plasma. The chromatographic analysis was performed on an Agilent C18 column (250 mm length x 4.6 mm ID, 5μm particle size), employing a mobile phase composed of a methanol and o-phosphoric acid (0.1% in water) mixture in a ratio of 75:25% v/v. The flow rate was set at 0.7 ml/min, and detection was conducted at 260 nm using an Agilent 1100 instrument equipped with an auto sampler, quaternary gradient pump (G-1314), and diode-array detector (DAD). Linearity was observed in concentration ranges of 5-25 μg/ml and 10-50 μg/ml for Desloratadine and Montelukast sodium, respectively. The regression equations for Desloratadine and Montelukast sodium were Y=58.18x-4.414 and Y=81.64x+1.394, respectively, with correlation coefficients of 0.9988 and 0.9992.The percentage recovery was determined to be 96.70% for Desloratadine and 100.21% for Montelukast sodium. The limits of detection (LOD) for Desloratadine and Montelukast sodium were found to be 0.14318 and 0.113935, respectively, while the limits of quantification (LOQ) were determined as 0.433879 and 0.345258, respectively. Both drugs exhibited a regression value of 0.999. Desloratadine demonstrated high susceptibility to basic degradation and low susceptibility to hydrolytic degradation, while Montelukast sodium was susceptible to basic conditions. The relative standard deviation for intra-day precision of Desloratadine and Montelukast sodium was 0.25% and 0.14%, respectively, and for inter-day precision, it was found to be 0.25% and 0.28%, respectively. DOI: https://doi.org/10.52783/jchr.v13.i4.134

Comparative Economic Benefits of Different Oat Varities in Rainfed Areas of Pothwar, Pakistan

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Effect of 3 Key Factors on Average End to End Delay and Jitter in MANET

A mobile ad-hoc network (MANET) is a self-configuring infrastructure-less network of mobile devices connected by wireless links where each node or mobile device is independent to move in any desired direction and thus the links keep moving from one node to another. In such a network, the mobile nodes are equipped with CSMA/CA (carrier sense multiple access with collision avoidance) transceivers and communicate with each other via radio. In MANETs, routing is considered one of the most difficult and challenging tasks. Because of this, most studies on MANETs have focused on comparing protocols under varying network conditions. But to the best of our knowledge no one has studied the effect of other factors on network performance indicators like throughput, jitter and so on, revealing how much influence a particular factor or group of factors has on each network performance indicator. Thus, in this study the effects of three key factors, i.e. routing protocol, packet size and DSSS rate, were evaluated on key network performance metrics, i.e. average delay and average jitter, as these parameters are crucial for network performance and directly affect the buffering requirements for all video devices and downstream networks

Drilling High Precision Holes in Ti6Al4V Using Rotary Ultrasonic Machining and Uncertainties Underlying Cutting Force, Tool Wear, and Production Inaccuracies

Ti6Al4V alloys are difficult-to-cut materials that have extensive applications in the automotive and aerospace industry. A great deal of effort has been made to develop and improve the machining operations of Ti6Al4V alloys. This paper presents an experimental study that systematically analyzes the effects of the machining conditions (ultrasonic power, feed rate, spindle speed, and tool diameter) on the performance parameters (cutting force, tool wear, overcut error, and cylindricity error), while drilling high precision holes on the workpiece made of Ti6Al4V alloys using rotary ultrasonic machining (RUM). Numerical results were obtained by conducting experiments following the design of an experiment procedure. The effects of the machining conditions on each performance parameter have been determined by constructing a set of possibility distributions (i.e., trapezoidal fuzzy numbers) from the experimental data. A possibility distribution is a probability-distribution-neural representation of uncertainty, and is effective in quantifying the uncertainty underlying physical quantities when there is a limited number of data points which is the case here. Lastly, the optimal machining conditions have been identified using these possibility distributions.journal articl

Functional and radiological outcome of both bone fracture forearm in children managed with titanium elastic nailing system

Background: Forearm diaphyseal fracture is one of the three common upper limb fractures in the pediatric population. With many known methods of treatment available, the authors present their experience of managing these injuries by titanium elastic nailing system. Methods: The present study was a prospective study of 3 years duration which included 50 patients. All patients underwent elastic nailing of both radius and ulna in the same sitting. Analysis of pre-operative and post-operative radiographs of forearm, taken in two orthogonal views, was done. Final functional outcome was graded clinically by using criteria laid down by Price et al. Results: Good to excellent results were achieved after elastic nailing of forearm fractures in all the children. In this study, bony union was achieved in a mean time of 8.36 weeks, range being 6 to 14 weeks. No case of non-union was observed in the present study. Pin tract infection and skin irritation were the most common complication observed. Conclusions: Elastic stable intramedullary nailing is a safe and reliable method for internal fixation, giving predictably good functional results in paediatric both bone forearm fractures