Dalat University Journal of Science / Tạp chí khoa học Đại học Đà Lạt
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SURVEY AND PROPOSED METHOD TO DETECT ADVERSARIAL EXAMPLES USING AN ADVERSARIAL RETRAINING MODEL
Get PDFArtificial intelligence (AI) has found applications across various sectors and industries, offering numerous advantages to human beings. One prominent area where AI has made significant contributions is in machine learning models. These models have revolutionized various fields, benefiting society in numerous ways, from self-driving cars and intelligent chatbots to automated facial authentication systems. However, in recent years, machine learning models have been the target of various attack methods. One common and dangerous attack method is adversarial attack, where modified input images can cause misclassification or erroneous predictions by the models. To confront that challenge, we present a novel approach called adversarial retraining that uses adversarial examples to train machine learning and deep learning models. This technique aims to enhance the robustness and performance of these models by subjecting them to adversarial scenarios during the training process. In this paper, we survey detection methods and propose a method to detect adversarial examples using YOLOv7, a commonly used intensive research model. By training adversarial retraining and conducting experiments, we show that the proposed method is an effective solution for helping deep learning models detect certain cases of adversarial examples
FACTORS INFLUENCING ENGLISH LEARNING MOTIVATION: A STUDY OF THE PERSPECTIVES OF NON-ENGLISH MAJORS AT A PUBLIC UNIVERSITY IN HANOI, VIETNAM
Get PDFThe purpose of this study was to explore the internal and external factors that motivate university students to learn English. The subjects were 30 non-English majors at a university in Hanoi, Vietnam, who had completed at least three semesters of university-level English. All of the students participated in semi-structured interviews. The interviews revealed that extrinsic orientation, teachers, and peers substantially improved learning persistence among the students, while unattractive learning materials and a lack of authentic communicative activities contributed to learning demotivation. The study also provided insightful recommendations to enhance student motivation in the EFL classroom
INTERTEXTUALITY IN THE NOVELS OF ORHAN PAMUK
Get PDFThis study focuses on interpreting intertextuality in the novels by Orhan Pamuk in terms of dialogue with Turkish historical, cultural, and social discourse, focusing on mechanisms of intertextual citation and the integration and mixing of genres. Research results show that his novels address many issues in the social life of Turkey, a country with extremely important geopolitics, acting as a bridge for Eastern and Western cultural interference and dialogue. Recreating a chaotic hyperreality, Pamuk reveals his sense of humanity in modern life. The mechanisms of intertextual citation and integration and mixing of genres are fully utilized by Pamuk to expand the dimension of reality, increase openness, and continuously generate meaning for the text. Based on the analysis of intertextuality in Pamuk’s novels, this study provides both theoretical and practical insights that open up a framework for reference regarding the current state of literary research and creation in Vietnam
APPLYING THE GENETIC ALGORITHM AND QUANTUM CHEMICAL CALCULATIONS TO STUDY THE STRUCTURE OF THE Sc2B6 CLUSTER AND ITS CO ADSORPTION
Get PDFWe used the genetic algorithm and quantum chemical calculations to study the structures of the Sc2B6 cluster. The global minimum energy structure has the shape of a hexagonal bipyramid with an Sc atom at each apex and a B6 ring that belongs to the D6h point group symmetry. The second most stable structure has the Cs point group symmetry and can be formed by substituting a Sc atom for a B atom in the ring and a B atom for Sc in one of the apexes. From the computational results, the Sc2B6 cluster is found to be a good candidate to form a nanomaterial for treating CO gas
COULOMB DRAG RESISTIVITY IN DOUBLE-LAYER GRAPHENE: INHOMOGENEITY EFFECTS
Get PDFWe investigate Coulomb drag resistivity in a double-layer system consisting of two parallel monolayer graphene sheets. In calculations, we employ the random-phase approximation to determine the polarizability functions of the graphene layers and the frequency-dependent dielectric function of the structure, taking into account inhomogeneity effects of the background dielectric. Our numerical calculations reveal that Coulomb drag resistivity in double-layer graphene systems steadily increases with increasing temperature but quickly decreases as the interlayer separation increases. The drag resistivity between the two layers in the case of an inhomogeneous background dielectric is substantially larger than that in the case of a homogeneous one. In addition, both the value and the imbalance in carrier density in the layers lead to noticeable changes in Coulomb drag resistivity in the system. Our study results are useful in graphene-based structure applications
RURAL TOURISM DEVELOPMENT: HOW TO ATTRACT THE RESIDENTS’ PARTICIPATION? A STUDY OF THE CENTRAL HIGHLANDS, VIETNAM
Get PDFThe main aim of this study is to measure the impact of factors including sense of place, perceived benefits, perceived costs, and quality of life on the residents’ willingness to assist in rural tourism development in the Central Highlands, Vietnam. SPSS software was used to check the suitability of the model, and partial least squares structural equation modeling (PLS-SEM) was used to run a regression analysis of the balance equations and to measure the level of impact between factors. The regression equation then provided the interaction between the variables as the explanation for the hypotheses. The statistical results of 443 survey responses were analyzed from five provinces of this region. Quality of life showed a positive impact on residents’ willingness to support rural tourism development, while perceived benefits related to cultural and social issues had negative impacts. These findings and the discussion may aid policymakers in planning strategies for rural tourism development in the Central Highlands, Vietnam
SEASONAL VARIATION OF IN SITU PHYTOPLANKTON PHOTOSYNTHETIC PROPERTIES IN NHA TRANG BAY
Get PDFPhotosynthetic properties are essential for the evaluation of phytoplankton photosynthetic efficiency as well as their physiological status in different waters. The present study measured in situ minimum and maximum fluorescence (Fo, Fm), variable fluorescence (Fv), and photosynthetic efficiency (Fv/Fm) in Nha Trang Bay to estimate seasonal phytoplankton community responses to different environmental conditions. Photosynthetic efficiency of in situ phytoplankton in Nha Trang Bay varied from 0.03 to 0.55 among stations and sampling times. Stations near the shore (Cape Chut) and estuary had higher Fv/Fm values than offshore stations. Seasonal and spatial variation of photosynthetic efficiency along the transect from the river mouth to the open ocean reflected the impact of river inputs on phytoplankton communities. In situ measurements indicate the impacts of complex environmental conditions in Nha Trang Bay (e.g., light intensity and nutrients) on the physiological status and photosynthetic efficiency of phytoplankton
APPROACHING THE LEGENDARY HSUAN TSANG, THE PILGRIM AND SCHOLAR THROUGH THE LENS OF BIOGRAPHICAL CRITICISM
Get PDFHsuan Tsang, the Pilgrim & Scholar by Venerable Thich Minh Chau is notably intriguing due to its unique hybrid of historical narrative and biography. Examining this work from the perspective of biographical criticism not only holds scientific significance in elucidating the historical figure of Tang Hsüan-tsang but also sheds light on the activities of Venerable Thich Minh Chau through their notable similarities. This underscores Venerable Thich Minh Chau’s innovative contributions to storytelling and narrative structure, particularly when examined through the framework of biography and culture. By employing biographical criticism and integrating three specialized methods–psychological analysis, socio-cultural context, and interdisciplinary approaches–this paper analyzes the work focusing on biographical elements, travel accounts, and Buddhist studies. The aim is to clarify the depiction of Tang Hsüan-tsang, contributing to the research on Hsuan Tsang, the Pilgrim & Scholar as a resource for Buddhist studies and Vietnamese literature at the university level
ĐỘNG LỰC BÊN TRONG CỦA HỌC SINH SỬ DỤNG CÁC HOẠT ĐỘNG DỰA TRÊN TRÒ CHƠI
No full textThis study sought to determine the effects of game-based activities (GBAs) on students’ intrinsic motivation. The study employed a sequential explanatory mixed-methods approach using quantitative and then qualitative data to explore the impact of GBAs on intrinsic motivation. It also utilized lessons integrating GBAs into an ecosystem curriculum developed and adapted by the researcher for the study. Sixty-nine Grade 7 students from two sections of a public secondary school in Sorsogon, Philippines, participated in this study. One section with 34 students was assigned to an experimental group and exposed to GBAs developed for ecosystem lessons. The 35 students in the other section were assigned to a control group and taught with games using traditional teaching methods. Respondents completed a survey on the intrinsic motivation inventory (IMI) after the intervention. The survey results revealed a significant difference in the IMI scores of respondents (u = 327, N = 69, p = 0.05), and the integration of GBAs in ecosystem lessons for Grade 7 significantly improved students’ intrinsic motivation. Qualitative data analysis also revealed that GBAs specifically addressed students’ psychological needs in terms of interest or enjoyment, perceived competence, effort or importance, value or usefulness, and relatedness, which ultimately improved students’ intrinsic motivation. Integration of GBA into ecosystem lessons can improve students’ intrinsic motivation when GBAs align with learning goals and include interactive and engaging game elements. This study emphasized the effects of GBAs on intrinsic motivation and delved deeper into the specific context of science education in Grade 7, providing insights on how to harness GBAs effectively in specific educational settings. This study recommends the integration of GBAs into science education to enhance students’ motivation and improve their learning experiences and outcomes. A more comprehensive study of the effect of GBAs on students’ learning experiences is also recommended.
 
NONCLASSICAL PROPERTIES OF TWO-MODE DISPLACED FOCK STATE
Get PDFIn this paper, we investigate a variety of nonclassical properties of a two-mode displaced Fock state (TMDFS). Nonclassical properties such as sum squeezing, difference squeezing, antibunching effect, and the Cauchy-Schwarz inequality will be discussed analytically for the TMDFS. The results show that by changing the Fock state parameters between modes and the displacement parameter, the TMDFS exhibits enhanced nonclassical behaviors and makes a valuable contribution to quantum optics