Simulation of 2D surface flow in open channel using explicit finite difference method

2D surface flow models are useful to understand and predict the flow through breach, over a dyke or over the floodplains. This paper is aimed at the surface flows to study the behavior of flood waves. The open channel water flow in drains and rivers is considered in view of the fact that such flows are the source of flash flood. In order to predict and simulate the flood behavior a mathematical model with the initial and boundary conditions is established using 2D Saint-Venant partial differential equations. Next, the corresponding model is discretized by using the explicit finite difference method and implemented on MATLAB. For the testing and implementation purpose a simple rectangular flow channel is considered. The output parameters like height or depth of water, the fluid velocity and the volumetric flow rate are simulated numerically and visualized for the different time steps. The initial simulation results are useful to understand and predict the flood behavior at different locations of flow channel at specific time steps and can be helpful in early flood warning systems

A Lightweight Multifactor Authentication Scheme for Wireless Sensor Networks in the Internet of Things

Internet of Things (IoT) has become an information bridge between societies. Wireless sensor networks (WSNs) are one of the emergent technologies that work as themain force in IoT. Applications based on WSN includeenvironment monitoring, smart healthcare, user legitimacy authentication, and data security. Recently, many multifactoruser authentication schemes for WSNs have been proposedusing smart cards, passwords, as well as biometric features. Unfortunately, these schemes are shown to be susceptibletowards several attacks and these includes password guessing attack, impersonation attack, and Man-in-the-middle (MITM) attack due to non-uniform security evaluation criteria. In this paper, we propose a lightweight multifactor authentication scheme using only hash function of the timestamp (TS) and One Time Password (OTP). Furthermore, public key and private key is incorporated to secure the communication channel. The security analysis shows that the proposed scheme satisfies all the security requirement and insusceptible towards some wellknown attack (password guessing attack, impersonation attack and MITM)

Wearable Sensor Feature Fusion for Human Activity Recognition (HAR) : A Proposed Classification Framework

Human Activity Recognition (HAR) focuses on detecting people's daily regular activities based on time-series recordings of their actions or motions. Due to the extensive feature engineering and human feature extraction required by traditional machine learning algorithms, they are time consuming to develop. To identify complicated human behaviors, deep learning approaches are more suited since they can automatically learn the features from the data. In this paper, a feature-fusion concept on handcrafted features and deep learning features is proposed to increase the recognition accuracy of diverse human physical activities using wearable sensors. The deep learning model Long-Short Term Memory based Deep Recurrent Neural Network (LSTM-DRNN) will be used to extract deep features. By fusing the handcrafted produced features with the automatically extracted deep features through the use of deep learning, the performance of the HAR model can be improved, which will result in a greater level of accuracy in the HAR model. Experiments conducted on two publicly available datasets show that the proposed feature fusion achieves a high level of classification accuracy

Think Before You Answer : Fostering Deep Thinking among Students Through Moodle's Certainty-based Marking (CBM)

The quality of students' grasp of what they have learned in class is unclear to the instructors in multiple-choice assessments. Multiple-choice assessments do not allow students to elaborate on their answer arguments because they are evaluated simply on the answers they have supplied. The student’s level of understanding, on the other hand, is unknown to them. We used Moodle's certainty-based marking (CBM) to encourage students to think deeply before settling on their final answers to these tests and quizzes. This CBM method feedback will reveal whether the students are overconfident in their knowledge. CBM assigns weightage to correct and incorrect responses, as well as certainty levels that students must select before settling on their final answers. After using this method in quizzes and multiple-choice assessments, students are more in tune with their knowledge levels, and they are aware of the learning units that they need to improve in their courses. Through this study, both students and instructors will be able to have the benefits to assess the class knowledge level on units and topics learned in class

An analysis for chosen plaintext attack in elliptic curve cryptosystem based on second order lucas sequence

Elliptic Curve Cryptography is a cryptography based on the algebraic structure of elliptic curves over finite fields. The security of Elliptic Curve Cryptography depends on discrete logarithms that is much more difficult to challenge at equivalent key lengths. Lucas sequence is a sequence that satisfies the recurrence relation and is very useful for fast and reliable primality testing. Therefore, a cryptosystem had been developed which is analogous to Elliptic Curve Cryptosystem, and is based on second order Lucas sequence. This cryptosystem will be tested by using chosen plaintext attack. The chosen plaintext attack is one of the homomorphic attacks. It is a consequence of the multiplication structure and based on homomorphic nature. Thus, this paper reports a way the chosen plaintext attack succeed in Elliptic Curve Cryptosystem based on second order Lucas sequence

Security analysis of Lucas based El-Gamal Cryptosystem in the elliptic curve group over finite field using two types of GMITM attacks

The success of Garbage-man-in-the-middle (GMITM) attack relies on the possibility to access to the ”bin” of recipient in the cryptosystem. It is capable to recover the original plaintext by granting an entry to the ”bin”. There are basically two types of GMITM attacks, a polynomial attack and a homomorphic attacks. In this paper, an investigation was carried out to evaluate the polynomial structure of cryptosystem and the nature of a homomorphic attack on cryptosystem. The results show that the cryptanalyst could obtain the plaintext without knowing the secret number, a, b and R

Common modulus attack against Lucas based El-Gamal Cryptosystem in the elliptic curve group over finite field

Common modulus attack is one of the various homomorphic attacks based on homomorphism nature of cryptosystems. This type of attack requires a plaintext encrypted under same modulus while two encryption keys are relatively prime to each other. In this paper, an investigation was carried out to evaluate the nature of a homomorphic attack on the Lucas based El-Gamal Cryptosystem in the elliptic curve group over finite field. The attack can be proven by using extend Euclidean algorithm together with composite and reverse functions of Lucas and Fibonacci sequences. Results showed that common modulus attack can be used to obtain the original plaintexts. Thus, it is dangerous to send a plaintext to two different users using same modulus. Sender must use different modulus to communicate with two different users

Scienceploration 2023

The Scienceploration Camp is an initiative of the Centre for Pre-University Studies, UNIMAS (PPPU), which aims to increase the interest in science among secondary school students. It is also an effort taken by PPPU towards the achievement of Sustainable Development Goals 4 in providing equal quality education and promoting lifelong learning opportunities for all. On top of that, this camp supports Sarawak’s Digital Economy Strategy in nurturing an integrated ecosystem to foster inclusive digital society, by building the right foundations to grow our local digital economy

Students' understanding of equal and equality symbols in mathematics

This study aims to identify the Fonn 1 students' understanding of equal and equality symbols. The specific objectives are to investigate whether the fonn 1 students have problem in solving questions involving equations of one side such as "23+24 = 47"; to investigate whether the fonn 1 students have problem in solving. questions involving equations of both sides such as "23+24-16 = _+25-13"; to investigate whether the form 1 students have problem in translating the mathematic sentence into symbols and vice versa and to find out the definition of equal and equality symbols from the students view. In this study, instrument were taken from Oksuz,(2007) and Knuth et al, (2006). The instrument consists of 12 questions and the questions were divided into five sections. The instrument includes various types of questions including true/false question, multiple choice questions, fill out question, and open question sentences. In this study, the participants were 15 Fonn 1 students from the secondary school located in Petrajaya, Kuching. During the data collection, the students were given 30 minutes to complete the exercise. Then, the data were analyzed and the results were discussed. From the findings it is found that students do not have any problem in solving the equation with none rule violation which means the equation is on the left side while the equal symbol is on the right side for example "4 + 6 = 10". However, the students have a slight problem when given questions that violate the rules where the equation is on the right side and the equal symbol is on the left side for example "9 = 5 + 4". Apart from that, this study also found that the students has problem in solving equation that appear on both sides. When given question such as "4 + 6 = [ ] + 2", the students think that lOis the answer for the unknowns. It shows that students think that the answer should come after the equal symbol. Moreover, the students were not able to write the correct equation to represent the given situation. Most of the students write an equation that shows their understanding in arithmetic and not in tenns of algebraic thinking. It is also found that none of the students were able to use the equal symbol to show the relationship between the equations. The students think that the symbol is a symbol to show the answer or to represent the answer and this might be the cause of their misconception in the exercise. Therefore, further research on investigating the reason of each misconception should be done. In addition, a research on finding the appropriate instructional strategies to solve this problem can be done in the future. This will improve the students understanding in learning mathematics