HNUE Journal of Science Hanoi National University of Education
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DEVELOPING COGNITIVE LOAD OF GEOGRAPHIC INFORMATION IN TEACHING GRADE-10 GEOGRAPHY IN HIGH SCHOOL
Get PDFTrong dạy học địa lí, một trong những năng lực quan trọng cần hình thành cho người học là năng lực nhận thức khoa học Địa lí. Trong quá trình dạy học địa lí ở trường trung học phổ thông (THPT) năng lực nhận thức của học sinh được biểu hiện ở khả năng nắm bắt, hiểu và vận dụng các tri thức địa lí để hoàn thành tốt các nhiệm vụ học tập được giao. Năng lực nhận thức khoa học Địa lí được biểu hiện thông qua năng lực nhận thức thế giới theo quan điểm không gian và năng lực giải thích các hiện tượng và quá trình địa lí. Như vậy, thông qua việc phát triển năng lực nhận thức khoa học Địa lí, học sinh (HS) đồng thời sẽ phát triển được các phẩm chất và năng lực chung như năng lực tự học, tự chủ; năng lực giao tiếp, hợp tác; năng lực giải quyết vấn đề, sáng tạo và các năng lực địa lí khác như năng lực tìm hiểu địa lí; năng lực vận dụng kiến thức, kĩ năng đã học đáp ứng được mục tiêu dạy học địa lí theo chương trình giáo dục phổ thông 2018.In teaching geography, one essential competency is the cognitive load of geographic information. In the process of teaching geography in high schools, this competency is reflected in the students’ ability to grasp, understand, and apply geographical knowledge to complete assigned learning tasks. Geoscience cognitive capacity is expressed through the capacity to perceive the world from a spatial perspective and the capacity to explain geographical phenomena and processes. Developing this competency enables students to strengthen general qualities and abilities such as self-study, autonomy, communication, cooperation, problem-solving, and creativity while also enhancing subject-specific competencies aligned with the new general education program
STRONG-COUPLING PERTURBATION THEORY IN A SIMPLE AND EXACTLY SOLVABLE MODEL
Get PDFWe study strong-coupling perturbation theory in a simple and exactly solvable model. The divergence of the perturbative series is effectively addressed using the technique of continued fractions. The results obtained from perturbation theory show good agreement with the exact solutions. The calculations are straightforward, making them suitable for teaching quantum mechanics or other theoretical physics courses, as well as for application in more complex research studies.We study strong-coupling perturbation theory in a simple and exactly solvable model. The divergence of the perturbative series is effectively addressed using the technique of continued fractions. The results obtained from perturbation theory show good agreement with the exact solutions. The calculations are straightforward, making them suitable for teaching quantum mechanics or other theoretical physics courses, as well as for application in more complex research studies
GLOBAL ATTRACTORS TO THREE-DIMENSIONAL NAVIER-STOKES EQUATIONS WITH DAMPING AND FINITE DELAYS
Get PDFThe asymptotic behavior of solutions to the three-dimensional NavierStokes equations is a longstanding and challenging open problem, which has seen numerous important contributions in recent years. In this paper, we consider the NavierStokes equations with damping and delay terms on a bounded domain . Using the energy method, we prove the existence of global attractors, thus establishing the long-time stability and compactness of the solution set for this class of delayed fluid dynamic models.The asymptotic behavior of solutions to the three-dimensional NavierStokes equations is a longstanding and challenging open problem, which has seen numerous important contributions in recent years. In this paper, we consider the NavierStokes equations with damping and delay terms on a bounded domain . Using the energy method, we prove the existence of global attractors, thus establishing the long-time stability and compactness of the solution set for this class of delayed fluid dynamic models
THE SYNTHESIS, STRUCTURE OF TWO PLATINUM(II) COMPLEXES BEARING ARYLOLEFIN AND QUINOLIN-8-OL DERIVATIVE
Get PDFThe reaction of complex K[PtCl3(Eug)] with HOQCHO or complex [PtCl(Preug-1H)]2 with HOQ afforded two novel complexes [PtCl(Eug)(OQCHO)] (C1) and [Pt(Preug-1H)(OQ)] (C2), both obtained in high yields. Their structures were determined using elemental analysis, IR spectroscopy, and 1H NMR spectroscopy. The results confirmed that in both complexes, the amine ligand is deprotonated at the OH group and chelates the Pt(II) center through the N and O atoms. In C1, Eug coordinates to Pt(II) via the allylic C=C bond, while in C2, Preug-1H coordinates to Pt(II) not only through the allylic C=C bond but also via the C5 atom of the benzene ring. Additionally, C1 exists in two conformational forms in solution due to rotation of the CHO group around the C-C bond, leading to two distinct sets of signals in its 1H NMR spectrum.The reaction of complex K[PtCl3(Eug)] with HOQCHO or complex [PtCl(Preug-1H)]2 with HOQ afforded two novel complexes [PtCl(Eug)(OQCHO)] (C1) and [Pt(Preug-1H)(OQ)] (C2), both obtained in high yields. Their structures were determined using elemental analysis, IR spectroscopy, and 1H NMR spectroscopy. The results confirmed that in both complexes, the amine ligand is deprotonated at the OH group and chelates the Pt(II) center through the N and O atoms. In C1, Eug coordinates to Pt(II) via the allylic C=C bond, while in C2, Preug-1H coordinates to Pt(II) not only through the allylic C=C bond but also via the C5 atom of the benzene ring. Additionally, C1 exists in two conformational forms in solution due to rotation of the CHO group around the C-C bond, leading to two distinct sets of signals in its 1H NMR spectrum
CONSTITUENTS AND ANTIBACTERIAL ABILITY OF WATER BUG (Lethocerus indicus Lep.) ESSENTIAL OILS
Get PDFThe water bug, Lethocerus indicus Lep., is an aquatic insect commonly found in deep rice fields, lakes, ponds, and rivers in Vietnam. In this study, male specimens were collected from fields, ditches, ponds, and lakes in Dai Cuong commune, Ung Hoa district, Hanoi, Vietnam. The objective of this study is to determine the constituents and antibacterial properties of the essential oil extracted from L. indicus. Gas chromatography–mass spectrometry (GC-MS) analysis identified fifteen major components, primarily hydrocarbons and oxygenated hydrocarbons. In which, specifically, the essential oil comprised 12.41% monoterpenes, 25.12% sesquiterpenes, 21.98% alcohols, 1.79% aldehydes, and 36.63% esters. In particular, (E)-2-hexenol-acetate was the predominant component, accounting for 36.63%, and is believed to contribute to the characteristic aroma of the essential oil. The antibacterial activity of the essential oil was evaluated against six microorganisms: Staphylococcus aureus, Clostridium botulinum, Clostridium perfringens, Escherichia coli, Campylobacter jejuni, and Vibrio parahaemolyticus.The water bug, Lethocerus indicus Lep., is an aquatic insect commonly found in deep rice fields, lakes, ponds, and rivers in Vietnam. In this study, male specimens were collected from fields, ditches, ponds, and lakes in Dai Cuong commune, Ung Hoa district, Hanoi, Vietnam. The objective of this study is to determine the constituents and antibacterial properties of the essential oil extracted from L. indicus. Gas chromatography–mass spectrometry (GC-MS) analysis identified fifteen major components, primarily hydrocarbons and oxygenated hydrocarbons. In which, specifically, the essential oil comprised 12.41% monoterpenes, 25.12% sesquiterpenes, 21.98% alcohols, 1.79% aldehydes, and 36.63% esters. In particular, (E)-2-hexenol-acetate was the predominant component, accounting for 36.63%, and is believed to contribute to the characteristic aroma of the essential oil. The antibacterial activity of the essential oil was evaluated against six microorganisms: Staphylococcus aureus, Clostridium botulinum, Clostridium perfringens, Escherichia coli, Campylobacter jejuni, and Vibrio parahaemolyticus
ON STABILIZATION OF DISCRETE-TIME 2-D SYSTEMS IN ROESSER MODEL
Get PDFThis paper focuses on the stabilization problem of discrete 2-D linear systems described by the Roesser model. A tractable stability condition in terms of linear matrix inequalities is first reformulated. Then, two controller design schemes are developed to formulate stabilization conditions via state-feedback controllers (SFCs) and event-triggered controllers (ETCs). Numerical examples with simulations are given to illustrate the effectiveness of the design conditions.This paper focuses on the stabilization problem of discrete 2-D linear systems described by the Roesser model. A tractable stability condition in terms of linear matrix inequalities is first reformulated. Then, two controller design schemes are developed to formulate stabilization conditions via state-feedback controllers (SFCs) and event-triggered controllers (ETCs). Numerical examples with simulations are given to illustrate the effectiveness of the design conditions
EATING BEHAVIORS ASSOCIATED WITH THINNESS AMONG 9 TO 12-YEAR-OLD STUDENTS AT 915 GIA SANG PRIMARY AND SECONDARY SCHOOL, THAI NGUYEN CITY: A DECISION TREE ANALYSIS
Get PDFThinness is a persistent but understudied form of undernutrition among school-aged children in Vietnam, especially in peri-urban settings. This study focused on students aged 9 – 12 at Gia Sang Primary and Secondary School in Thai Nguyen, aiming to identify key eating behavior patterns associated with thinness using decision tree analysis as a data-driven approach for nutritional risk classification. A cross-sectional study was conducted with 157 students at Gia Sang Primary and Secondary School in Thai Nguyen, Vietnam. Nutritional status was assessed using body mass index-for-age Z-scores in accordance with WHO (2007) standards. Eating behaviors were measured using the validated Children’s Eating Behavior Questionnaire (CEBQ), comprising eight behavioral subscales. Anthropometric data were collected following standardized procedures. Pearson correlation analysis, logistic regression, and decision tree modeling were applied to examine associations and classify thinness risk. Results showed that 14.0% of participants were classified as thin and 11.5% as overweight, reflecting the double burden of malnutrition. Logistic regression analysis indicated that Satiety Responsiveness (SR) and Slowness in Eating (SE) were significant predictors of thinness (P < 0.05). More notably, decision tree analysis revealed distinct high-risk profiles: children with high Desire for Drinks (DD ≥ 3.8) and low SR (< 2.4) had an 80% probability of being thin, while those with low DD combined with low Food Fussiness (FF), Emotional Overeating (EOE) scores, and SE had a 62% probability. These findings highlight the added value of decision tree modeling in capturing complex interactions among eating behaviors associated with thinness. They also suggest the potential of using behavioral screening tools like the CEBQ for early identification of nutritional risk and for informing targeted, behaviorally tailored interventions within school-based health programs.Thinness is a persistent but understudied form of undernutrition among school-aged children in Vietnam, especially in peri-urban settings. This study focused on students aged 9 – 12 at Gia Sang Primary and Secondary School in Thai Nguyen, aiming to identify key eating behavior patterns associated with thinness using decision tree analysis as a data-driven approach for nutritional risk classification. A cross-sectional study was conducted with 157 students at Gia Sang Primary and Secondary School in Thai Nguyen, Vietnam. Nutritional status was assessed using body mass index-for-age Z-scores in accordance with WHO (2007) standards. Eating behaviors were measured using the validated Children’s Eating Behavior Questionnaire (CEBQ), comprising eight behavioral subscales. Anthropometric data were collected following standardized procedures. Pearson correlation analysis, logistic regression, and decision tree modeling were applied to examine associations and classify thinness risk. Results showed that 14.0% of participants were classified as thin and 11.5% as overweight, reflecting the double burden of malnutrition. Logistic regression analysis indicated that Satiety Responsiveness (SR) and Slowness in Eating (SE) were significant predictors of thinness (P < 0.05). More notably, decision tree analysis revealed distinct high-risk profiles: children with high Desire for Drinks (DD ≥ 3.8) and low SR (< 2.4) had an 80% probability of being thin, while those with low DD combined with low Food Fussiness (FF), Emotional Overeating (EOE) scores, and SE had a 62% probability. These findings highlight the added value of decision tree modeling in capturing complex interactions among eating behaviors associated with thinness. They also suggest the potential of using behavioral screening tools like the CEBQ for early identification of nutritional risk and for informing targeted, behaviorally tailored interventions within school-based health programs
DIFFERENTIAL VARIATIONAL INEQUALITIES VIA THE EXTENDED LASALLE’S INVARIANCE PRINCIPLE APPROACH
Get PDFIn this work, we establish an extended LaSalle’s invariance for a class of nonautonomous differential inclusions in Euclidean spaces. We also give sufficient conditions for the stability of an equilibrium of differential variational inequalities. Special cases as linear complementarity problems, based on LaSalle’s invariance in both autonomous and non-autonomous cases, are also studied in this paper.In this work, we establish an extended LaSalle’s invariance for a class of nonautonomous differential inclusions in Euclidean spaces. We also give sufficient conditions for the stability of an equilibrium of differential variational inequalities. Special cases as linear complementarity problems, based on LaSalle’s invariance in both autonomous and non-autonomous cases, are also studied in this paper
COMPARATIVE ASSESSMENT OF SOIL PROPERTIES IN ORGANIC, CONVENTIONAL, AND ABANDONED VEGETABLE CULTIVATION SYSTEMS IN VEGETABLE-GROWING AREAS OF HANOI
Get PDFThe application of fertilizers and agrochemicals in crop cultivation can significantly affect the physicochemical properties and nutrient composition of vegetable soils. In this study, soil samples were collected from eighteen vegetable fields managed under organic farming, conventional farming, and abandoned land-use systems across four specialized vegetable-producing communes in southern Hanoi. Results indicated that the cultivated soils were mainly loamy and sandy loam soils, both suitable for vegetable production. Physical, chemical, and nutrient parameters varied among cultivation systems. Organic farming soils showed the best quality in terms of physicochemical properties, organic matter content, and macro- and micronutrient contents. Conventional farming soils contained higher concentrations of macro- and micronutrients compared to abandoned fields, but exhibited lower organic matter content. Organic farming soils have BD: 1.08 g/cm3, PD: 2.62 g/cm3, OC: 1.34%, N: 0.12%, P2O5: 0.21%, K2O: 0.95, CEC: 13.07 cmol/kg of air-dried soil. Conventional farming soils exhibited BD: 1.18 g/cm3, PD: 2.47 g/cm3, OC: 1.09%, N: 0.10%, P2O5: 0.35%, K2O: 0.74, CEC: 11.87 cmol/kg of air-dried soil. The cultivation of organic vegetables not only ensures a safe and health-promoting food supply for humans but also contributes to environmental protection and the improvement of soil quality. This practice represents a sustainable approach to soil utilization and should be actively promoted for wider adoption.The application of fertilizers and agrochemicals in crop cultivation can significantly affect the physicochemical properties and nutrient composition of vegetable soils. In this study, soil samples were collected from eighteen vegetable fields managed under organic farming, conventional farming, and abandoned land-use systems across four specialized vegetable-producing communes in southern Hanoi. Results indicated that the cultivated soils were mainly loamy and sandy loam soils, both suitable for vegetable production. Physical, chemical, and nutrient parameters varied among cultivation systems. Organic farming soils showed the best quality in terms of physicochemical properties, organic matter content, and macro- and micronutrient contents. Conventional farming soils contained higher concentrations of macro- and micronutrients compared to abandoned fields, but exhibited lower organic matter content. Organic farming soils have BD: 1.08 g/cm3, PD: 2.62 g/cm3, OC: 1.34%, N: 0.12%, P2O5: 0.21%, K2O: 0.95, CEC: 13.07 cmol/kg of air-dried soil. Conventional farming soils exhibited BD: 1.18 g/cm3, PD: 2.47 g/cm3, OC: 1.09%, N: 0.10%, P2O5: 0.35%, K2O: 0.74, CEC: 11.87 cmol/kg of air-dried soil. The cultivation of organic vegetables not only ensures a safe and health-promoting food supply for humans but also contributes to environmental protection and the improvement of soil quality. This practice represents a sustainable approach to soil utilization and should be actively promoted for wider adoption
OPTIMAL ATTENUATION CONTROL OF 2-D POSITIVE ROESSER SYSTEMS WITH BOUNDED DISTURBANCES
Get PDFIn this paper, performance analysis and controller design problems subject to an optimal attenuation level are studied for 2-D positive systems with bounded input disturbances. First, some novel comparison techniques for state estimations subject to peak values of external disturbances are presented to derive a characterization for l∞-induced norm of the input-output operator. Then, we derive the necessary and sufficient linear programming (LP) conditions for obtaining a controller gain of an l∞-induced performance with a prescribed attenuation level. Numerical examples are given to illustrate the effectiveness of the proposed method.In this paper, performance analysis and controller design problems subject to an optimal attenuation level are studied for 2-D positive systems with bounded input disturbances. First, some novel comparison techniques for state estimations subject to peak values of external disturbances are presented to derive a characterization for l∞-induced norm of the input-output operator. Then, we derive the necessary and sufficient linear programming (LP) conditions for obtaining a controller gain of an l∞-induced performance with a prescribed attenuation level. Numerical examples are given to illustrate the effectiveness of the proposed method