Sentiment Analysis on Covid-19 Vaccination Tweets using Naïve Bayes and LSTM

Social media is one platform where people share their opinions and views on different topics, services, or behaviors that happen around them. Since the COVID19 pandemic that started at the end of 2019, it has been a topic on which people express their sentiments. Recently, the COVID19 vaccination programs have got a lot of responses. In this paper, we have proposed two models: one based on the machine learning approach: Naive Bayes & the other based on deep learning: LSTM, whose goal is to know the sentiment of Asian region tweets towards the vaccine through sentiment analysis. The data were extracted with the help of Twitter API from March 23, 2021, till April 2, 2021. The extraction approach contains keywords with geocoding of some of the Asian countries, especially Nepal, India and Singapore. After collecting data, some preprocessing such as removing numbers, non-English & stop words, removing special characters, and hyperlinks were done. The polarity of tweets was assigned using the Text blob library. The tweets were classified into one of the three: positive, negative, or neutral. Now the data were preprocessed with the splitting of tweets into training & testing sets. Both the models were trained & tested using 10767 unique tweets. This experiment shows that a number of people in these three countries (Nepal, India and Singapore) have positive sentiment towards the vaccine and are taking the first dose of Covid19 vaccine. At last, the accuracy of the LSTM model was found to be 7% greater than that of the Naive Bayes-based model.

Digital Ultrasonic Sensing Device with Programmable Frequency: Development and Analysis

Ultrasonic wave is widely used in Structure Health Monitoring (SHM) systems. A piezoelectric transducer (PZT) is one of the most widely used sensors to acquire the structure's ultrasonic wave. As today's world is digital, it is necessary to digitize the traditional analog PZT sensing system. This paper describes the development and analysis of a digital ultrasonic sensing device (DUSD) for PZT sensors. We removed the complexities of the analog circuit by interfacing the microcontroller directly with the charge amplifier circuit. The microcontroller used in this research is a 32-bit ARM Cortex-M4 with in-built FPU (Floating Point Unit) and DSP (Digital signal processing) instructions. These features make it possible to compute complex signal processing algorithms and methods in the controller itself. The developed sensing device can communicate with the user and other devices using Universal Asynchronous Receiver/Transmitter (UART). The user can select cut-off frequencies of both high pass filters (HPF) and low pass filters (LPF) as well as types of data (ultrasonic waves, damage index) that the user wishes to collect from the device. To illustrate the proficiencies of the device, the ultrasonic wave was collected and evaluated to detect the damage in the test specimen.

Application of Lee Model Curve on Fitting of Discharge Current Curve of Plasma Focus Device

A dense plasma focus is a table top machine producing a short-lived extremely popular plasma and cause fusion. Lee Model Code is a computer-based visual basic simulation package, which was successfully utilized in the plasma focus devices. The dynamics of plasma focus discharge is quite complicated, so to review and simplify the complication Lee Model couples electrical circuit with the plasma focus dynamics, radiation and therefore the thermodynamics. This enables us to simulate all of the gross focus properties. In this paper the numerical experiments are carried out to compute the current trace as a function of time for plasma focus (PF) device NX2. Results obtained by the numerical experiments are compared with the published laboratory measured data. This current fitting is completed to get the model parameters.

Utilization of Personal Protective Equipment in Construction Industry of Nepal

Construction industry is one of the most dangerous industries worldwide. Use of personal protective equipment reduces injuries associated with it. This study has been undertaken to find out safety improvement measures and enforcement of statutory provisions available for safety practices, to analyze the current issues regarding application of PPE and to identify key factors preventing effective use of safety wears in construction industry of Nepal. The methodology adopted consists of comprehensive review of literature and questionnaire survey.100 sets of questionnaires to the professionals and 385 to the site operatives were administered. The collected data were analyzed using relative mean score and independent samples test and then ranked as per their significance. This study concluded that routine check of scaffold and ladder, in house safety training, daily consciousness of safety practice, etc. will improve workers’ safety practices. Wearing PPE can help protect from work related injuries, feeling responsible for wearing PPE all the times, asking supervisors for provision of appropriate and adequate PPE but the management has not maintained sufficient stock of appropriate safety wears are the current issues regarding application of PPE. Based on the result of Independent Samples T-test, safety wears are not comfortable to wear with, operatives’ engagement in improper conduct that could endanger their safety, ineffective communication between safety managers and workers are the major factors preventing effective use of safety wears.

Techno-Economic Analysis of the placement of the Capacitor in the Integrated Nepal Power System

With the increasing load demand, Integrated Nepal Power System (INPS) is facing a stiff challenge to maintain voltage profile within the standards and reduce system loss. Among the loss reduction strategies, an immediate solution would be installation of reactive power compensators at the grid substations. The power flow study of existing system is performed and a genetic algorithm is used to find optimum placement of suitable size of the capacitor banks to be added in system. 6 substations with a total reactive power supply of 80 MVAR was determined as optimal size and location and the installation is also financially feasible. Moreover, the analysis of capacitors placed at the varying voltage levels implied that the most suitable voltage level for the capacitor installation is 11kV.

Deterministic and Stochastic Holling-Tanner Prey-Predator Models

A modified version of the so called Holling-Tanner prey-predator models with prey dependent functional response is introduced. We improved some new results on Holling-Tanner model from Lotka-Volterra model on real ecological systems and studied the stability of this model in the deterministic and stochastic environments. The study was focused on three types of stability, namely, stable node, spiral node, and center. The numerical schemes are employed to get the approximated solutions of the differential equations. We have used Euler scheme to solve the deterministic prey-predator model and we used Euler-Maruyama scheme to solve stochastic prey-predator model.