Stability of Discrete-Time Matrix Polynomials

This paper derives conditions for the stability of discrete-time systems that can be modeled by a vector difference equation, where the variables are m x 1 vectors and the coefficients are m x m matrices. Stability of the system is related to the locations of the roots of the determinant of a real m x m matrix polynomial of nth order. In this case, sufficient conditions for the system to be stable are derived. The conditions are imposed on the infinity norm of two matrices constructed from the coefficient matrices and do not require the computation of the determinant polynomial. The conditions are the extensions of one of the Jury sufficient conditions for a scalar polynomial. An example is used to illustrate the application of the sufficient condition

Assessment of High School Students’ Learning and Development of Qualities and Competencies: A Case Study

This study aims to assess high school students' learning outcomes, their achievement of goals and fulfilling academic requirements and how the entire teaching and learning process takes place. The study, consisting of an experimental group and a control group was conducted for pre-test and post-test comparisons of the academic performance of 88 10th grade students. 44 students were selected as the experimental group that underwent a specific teaching strategy to monitor their development of qualities and competencies in one semester, and the remaining 44 students acted as the control group. The data collected after the tests were analyzed using SPSS software (V20). The results showed that the students in the experimental group had better academic results than those in the control group. The findings of this study have implications for policy, further research as well as approaches for the assessment of students’ development of qualities and competencies in Vietnam

DEVELOPING THE INFORMATION TECHNOLOGY APPLICATION COMPETENCE OF TEACHERS IN ONLINE TEACHING

Developing the competence to use information technology in teaching is one of the important occupational competencies for teachers in the digital age. Information technology application development has many implications in promoting the training process to train and develop students, in accordance with the actual conditions of education in Vietnam and the general trend of the world is essential.Research paper on needs assessment using information technology of teachers in online teaching, proposing the process of identifying the structure of information technology competencies and requirements for capacity development to use information technology in online teaching of training institutions. The parameters in this paper present an empirical research result to address the need to develop the information technology application competence in online teaching, necessary to successful organize online teaching with a variety of theoretical and practical pedagogies in technology in education

Assessment of Information Technology Use Competence for Teachers: Identifying and Applying the Information Technology Competence Framework in Online Teaching

This paper proposes a theoretical framework as a foundation for building information technology competence framework and the requirements for using information technology competence of teachers in online teaching at training institutions. The parameters in this paper survey was conducted on sample space (n = 342) and 42 expert opinions to identify information technology competence framework with criteria and skill sets necessaries to successfully organize online teaching. This paper discusses on teaching developing information technology competence to change minds and develop teachers' competency to meet the online teaching trend of the digitalization today. So, building information technology competence framework in online teaching has many meanings in training process contribute to improving the learning capacity of students

Spanning Cacti for Structurally Controllable Networks

Master'sMASTER OF SCIENC

EFFECT OF PRECURSOR MATERIALS AND HYDROTHERMAL TIME ON THE MORPHOLOGY, MICROSTRUCTURE AND PHOTOCATALYTIC ACTIVITY OF TiO2 NANOTUBES

In this study, effects of precursor materials and hydrothermal reaction time on the morphology, microstructures and photocatalytic activity of TiO2 nanotubes (TNTs) were investigated. Results show that the selection of nanopowder TiO2 precursors and hydrothermal time has significantly affected the morphology, microstructure and photocatalytic property of TiO2 nanotubes. TNTs–Merck was fabricated from TiO2–Merck precursor at 130 °C for 22 h possesses a uniform structure with a range of the diameter of ~ 10 nm and length of ~ 100 nm.

One-Dimensional Modeling of Triple-Pass Concentric Tube Heat Exchanger in the Parabolic Trough Solar Air Collector

The parabolic trough solar collector has a very high absorber tube temperature due to the concentration of solar radiation. The high temperature leads to large heat loss to the environment which reduces efficiency of the parabolic trough collector. The heat loss reduction can be obtained by adopting a multi-pass fluid flow arrangement. In this chapter, airflow travels in three passes of the receiver to absorb heat from the glass covers and absorber tube to decrease surface temperatures. 1D mathematical model is developed to evaluate effective efficiency and the temperature distribution of surfaces and fluid. The mathematical modeling is based on air temperature gradients and solved by a numerical integration. Diameter ratios of outer glass to inner glass (r23) and inner glass to absorber tube (r12), Reynolds number (Re), and tube length (L) are varied to examine the efficiency and the temperature distribution. Results showed that the highest efficiency is archived at r23 = 1.55 and r12 in the range of 1.45 to 1.5. The efficiency increases with Re and decreases with L due to dominant heat transfer in terms of thermohydraulic behavior of a concentrating solar collector. With the optimum ratios, absorber tube temperature can reduce 15 K compared with another case

Board Independence and Financial Performance: Empirical Evidence on Mediating Role of Market Competition From the Vietnamese Market

Purpose: The aim of this study is to examine the effect of board independence on the financial performance of companies listed on the Vietnamese stock exchanges with the mediating role of market competition.   Theoretical framework: The topic is based on agency theory, resource dependency theory and stewardship theory. The independence of the board of directors (BOD) is measured in two aspects: the duality and the non-executive members of BOD. This study approaches the measurement of market competition according to the Herfindahl-Hirschman index (HHI). After calculating the HHI, the study will classify companies in a highly competitive market or a low competitive market.   Design/methodology/approach: The study uses secondary data from the financial statements of companies listed on the Vietnamese stock market with the collection period from 2016 to 2020. The data analysis methods comprise of Pooled ordinary least squares (OLS), Fixed effects model (FEM), Random effects model (REM) and Generalized method of moments estimation (GMM).   Findings: The results of GMM showed that CEO duality is found to have a negative effect on the financial performance of listed firms. Meanwhile, the statistical evidence shows that the percentage of non-executive board members and market competition positively affect the financial performance. In addition, the evidence showed that market competition could reduce the positive influence of the percentage of non-executive board members on financial performance of listed companies.   Research, Practical & Social implications: The study has proposed some governance implications to improve the financial performance of listed firms such as limiting CEO duality, increasing the percentage of non-executive board members and empower the management board in a highly competitive market and choosing the appropriate size of the board.   Originality/value: The value of the study is to provide more scientific basis for policy makers in Vietnam and help listed companies choose and make decisions related to BOD to improve financial efficiency

Application of HEC-HMS model and satellite precipitation products to restore runoff in Laigiang river basin in Vietnam

The Laigiang river basin in the South Central Coast of Vietnam plays an important role in the socio-economic development of Binhdinh Province. In recent decades, the region has experienced commonly flooding in vast areas. This research aims to simulate event-based rainfall-runoff modelling, a historical flood event in December 2016, by applying the HEC-HMS model and rainfall data from CHIRPS. The CHIRPS data is an acceptable potential data input of the hydrology model. These have been confirmed through reliable validation indexes: The peak flood flow rate of 2,542.6 m3/s corresponds to the flood frequency of 5%; NSE with the value at 0.95; R2 coefficient reached 0.87; PBIAS being around 0.45, and PFC being at 0.89. It shows better performance in the rainy season than in the dry season. Inclusive, the CHIRPS rainfall data set and the HEC model could be used for some operational purposes in weather forecasting, especially for flood warnings in river basins in the South Central Coast, Vietnam