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Refugia have been perceived as a major role in structuring species biodiversity, and understanding the impacts of this force in a community assembly with prey–predator species is a difficult task because refuge process can interact with different ecological components and may show counterintuitive effects. To understand this problem, we used a simple two-species model incorporating a functional response inspired by a Holling type-II equation and a prey refuge mechanism that depends on prey and predator population densities (i.e., density-dependent prey refuge). We then perform the co-dimension one and co-dimension two bifurcation analysis to examine steady states and its stability, together with the bifurcation points as different parameters change. As the capacity of prey refuge is varied, there occur critical values i.e., saddle-node and supercritical Hopf bifurcations. The interaction between these two co-dimension one bifurcations engenders distinct outcomes of ecological system such as coexistence of species, bistability phenomena and oscillatory dynamics. Additionally, we construct a parameter space diagram illustrating the dynamics of species interactions as prey refuge intensity and predation pressure vary; as the two saddle-node move nearer to one another, these bifurcations annihilate tangentially in a co-dimension two cusp bifurcation. We also realised several contrasting observations of refuge process on species biodiversity: for instance, while it is believed that some refuge processes (e.g., constant proportion of prey refuge) would result in exclusion of predator species, our findings show that density-dependent prey refuge is beneficial for both predator and prey species, and consequently, promotes the maintenance of species biodiversity.

In this paper, we construct a new Lyapunov function for a variety of SIR and SEIR model in epidemiology. Lyapunov functions are used to show that when the basic reproduction ratio is less than or equal to one, the disease-free equilibrium is globally asymptotically stable and the basic reproduction ratio is greater than one, and the endemic equilibrium is also globally asymptotically stable for both models.

This study aims to investigate the students’ perceptions of Teaching and Learning Science and Mathematics in English (PPSMI) in Universiti Kebangsaan Malaysia (UKM). Among the information that can be used to achieve this aim are students’ views and feedbacks. A survey was conducted to gather views of students from the Faculty of Education (FPEND) and the Faculty of Science and Technology (FST). Statistical analysis was performed on the results of the survey. Our findings show that students from these two faculties tend to have a positive view towards PPSMI in UKM. However, given choices, they are more likely to prefer teaching and learning Science and Mathematics in Malay language, and they believed that the teaching and learning of Science and Mathematics is more effective in Malay medium.

The policy change of teaching Mathematics and Science from Malay to English language, which started in 2003 in school given an impact to the teaching and learning process in Public Higher Learning Institutions, including Universiti Keban Malaysia (UKM). Consequently, UKM administrators have directed all faculties offering Mathematics and Science cour follow the change starting with the first year courses. It is suggested that 30% of the courses is to be conducted in English 50% and 70% of the courses offered in the following second and third year, respectively would be conducted in English study aims at gauging the readiness of lecturers from the School of Mathematical Sciences (PPSM) to conduct courses in E from the perception of students. Questionnaires are distributed to first year students from the Faculty of Science and Techn (FST) and also from the Faculty of Education (FPEND) for the academic session of 2009/2010. From the results of the stud found that the students are generally satisfied with the teaching and learning conducted in English at the School of Mathem Sciences.

Malay language, the national language of Malaysia has been the medium of instruction for Science and Mathematics for the past four and a half decades in Malaysia. The government however changed the medium of instruction of these subjects to English in January 2003. The “Teaching and Learning of Science and Mathematics in English” (PPSMI) policy was implemented in all primary and secondary schools. It aims to improve the English language proficiency among students as well as the learning and achievement level in science and mathematics. This paper presents findings of the study on students’ inclination towards English language as medium of instruction in teaching and learning of Science and Mathematics in Higher Learning Institutions in Malaysia. The respondents were 291 undergraduate students from the Faculty of Science and Technology (FST) and Faculty of Education (FPEND) of Universiti Kebangsaan Malaysia (UKM). A questionnaire pertaining to students’ inclination was used as research instrument. Using descriptive statistics, ANOVA and t-test, the study found that undergraduate students of FST and FPEND had an inclination towards English as medium of instruction in the teaching and learning of Science and Mathematics. Using the Post-Hoc test, it is found that Indian students and students from other races than Malay and Chinese have greater inclination towards English as medium of instruction in teaching and learning of Science and Mathematics in UKM for both faculties. However, FST students who studied in Mandarin and Tamil at pre-university level (STPM) had higher inclination compared to those who used Malay language or even English.

In this paper we share our experience of conducting a mathematics camp to a group of 16-years-old school students. This camp is special since throughout their learning history, the students, like most school students in Malaysia, are only exposed to the academic side of mathematics. By this we mean the emphasis given by the school is only on academic achievement measured by the string of A's in the examination results. Of course in order to achieve this, the preferred mode of teaching and learning is geared towards drill and practice. None of the students from this group have experienced “outdoor” mathematics as to be given in this camp. The camp which consisted of several hands-on activities and done in small groups was conducted outdoors in a very relaxed and light-hearted atmosphere. The activities aimed at introducing several areas of mathematics such as group theory and number theory and their relevance to our everyday live. One niche activity which is considered as ethno-centric was also conducted. Indeed it exposed to the students the mathematical elements in the Malay culture. At the end of the camp questionnaires were distributed to the students to gauge their reaction to this mode of learning. A chi-squared test conducted showed that there was no relationship between student's understanding on the mathematics camp's module with their streams, hence the modules are applicable to both pure science and social science stream. In all, students were satisfied with the overall conduct of the mathematics camp, where they felt that this camp was very useful and helped improve their mathematical skills and knowledge.

In this paper, we introduce and study two new classes of functions called weakly b-θ-open functions and weakly b-θ-closed functions by using the notions of b-θ-open sets and b-θ-closure operator. The connections between these functions and other related functions are investigated.