Real-time Detection of Vehicles Using the Haar-like Features and Artificial Neuron Networks

AbstractIn this document, a vehicle detection system is presented. This system is based on two algorithms, a descriptor of the image type haar-like, and a classifier type artificial neuron networks. In order to ensure rapidity in the calculation extracts features by the descriptor the concept of the integral image is used for the representation of the image. The learning of the system is performed on a set of positive images (vehicles) and negative images (non-vehicle), and the test is done on another set of scenes (positive or negative). To address the performance of the proposed system by varying one element among the determining parameters which is the number of neurons in the hidden layer; the results obtained have shown that the proposed system is a fast and robust vehicle detector

Students’ Alternative Conceptions and Teachers’ Views on the Implementation of Pedagogical Strategies to Improve the Teaching of Chemical Bonding Concepts

The concept of chemical bonding is a crucial one in chemistry that occurs throughout the school curriculum and forms the basis of many topics in chemistry. Furthermore, learning about chemical bonding allows the learner to make predictions and provide explanations regarding the physical and chemical properties of substances. However, chemical bonding has been cited as one of the most difficult chemistry concepts for many secondary and higher education students to understand, and therefore, teachers can find it difficult to teach this concept due to the complexity of the underlying theory as well as the need to use abstract models to represent chemical bonds. The teaching methods used in the implementation of the concept can also be challenging. The aim of this study is to reveal the difficulties and alternative conceptions encountered by Moroccan secondary school students when learning concepts related to chemical bonding, the main causes of these difficulties, and the strategies used by teachers to help students overcome these obstacles. In this study, we conducted a survey of 57 Moroccan secondary school physical science teachers by means of a questionnaire. The questionnaire, consisting of three parts, was used to collect the data. Each part contains closed questions, open questions, and multiple-choice questions. The analysis of the results highlights the difficulties and alternative conceptions most frequently made by the students, namely: the octet rule, the geometry of molecules, and the polarity of molecules. Factors contributing to students’ misconceptions include the nature of abstract concepts, the use of models, and the difficulty for teachers to explain certain concepts related to chemical bonding. The study also presents some suggestions for improving the teaching of chemical bonding, such as integrating information and communication technologies (ICT), diversifying the teaching tools used, and taking into account students’ pre-existing conceptions. This can help teachers, curriculum developers, and textbook authors make the subject easier for students and address their misconceptions