Geometry of singularities of a Pinchuk's map

We describe a singular variety associated to a Pinchuk's map and calculate its homology intersection. The result provides geometries of singularities of this Pinchuk's map

An algorithm to classify the asymptotic set associated to a polynomial mapping

We provide an algorithm to classify the asymptotic sets of the dominant polynomial mappings F: \C^3 \to \C^3 of degree 2, using the definition of the so-called "{\it fa\c{c}ons}" in \cite{Thuy}. We obtain a classification theorem for the asymptotic sets of dominant polynomial mappings F: \C^3 \to \C^3 of degree 2. This algorithm can be generalized for the dominant polynomial mappings F: \C^n \to \C^n of degree $d$, with any $(n, d) \in {(\N^*)}^2$

A remark on a polynomial mapping from \C^n to \C^n

We provide relations of the results obtained in the articles \cite{ThuyCidinha} and \cite{VuiThang}. Moreover, we provides some examples to illustrate these relations, using the software {\it Maple} to complete the complicate calculations of the examples. We give some discussions on these relations.Comment: arXiv admin note: text overlap with arXiv:1503.0807

RESEARCH ON FACTORS AFFECTING ONLINE SHOPPING INTENTION OF CUSTOMERS: THE EVIDENCE IN VIETNAM

Objective: The research clarifies the relationships among the four key factors: brand reputation, trust, customer service quality, and online shopping intentions.   Theoretical Framework: The research adopted the E-S-QUAL four dimensions to measure e-service quality, customer trust, and purchase intention in virtual environments. The research explores the role of seller reputation in the relationship between trust and online shopping by building a model with four variables, six hypotheses, and 21 observed variables.   Method: The snowball sampling technique was used. Quantitative research was used to evaluate and test the theoretical model with a sample size of N = 395 through the online survey. This study examined the scale through exploratory factor analysis (EFA), confirmatory factor analysis (CFA), and structural equation modeling (SEM).   Results and Discussion: The results show that the research scales achieve unidirectional reliability, convergent validity, and high discriminant validity. Brand reputation has a positive impact on customer service through trust. Trust has a positive impact on online shopping intention through customer service.   Research Implications: This study only examines the role of brand reputation in the relationship between trust, customer service quality, and online shopping intention. Other important factors that affect this relationship may not be mentioned in the research.   Originality/Value: The article recommends improving Vietnamese consumers' confidence and online shopping intention by offering solutions for consumers, electronic sellers, and related associations and organizations

Molecular Kondo effect in flat-band lattices

The Kondo effect of a single magnetic impurity embedded in the Lieb lattice is studied by the numerical renormalization group. When the band flatness is present in the local density of states, it quenches the participation of all dispersive electrons in the Kondo singlet formation, and reduces the many-body Kondo problem to a two-electron molecular Kondo problem. The two-electron analog of the many-body Kondo singlet, a quantum entanglement of two spins, is stable at low temperature, and the impurity contributions to thermodynamical and dynamical quantities are qualitatively different from that obtained in the conventional Kondo effect in systems without flat bands. The existence conditions of the molecular Kondo effect in narrow band systems are also discussed

ASSESSMENT OF THE POTENTIAL FOR DEVELOPMENT OF AGRITOURISM IN BINH DINH PROVINCE, VIETNAM

This study evaluates the potential for agritourism development in Binh Dinh Province, Central Vietnam. The analytical hierarchical process is used to determine the weights of four factors with 25 measurement criteria to assess agritourism potential. The research results show that Binh Dinh Province has great agritourism potential based on four evaluation factors, including (1) local agricultural tourism resources, (2) the trend for agritourism development and the agritourism market, (3) the local community’s willingness, and (4) the supporting activities of the local government. In particular, the local agricultural tourism resources factor received the highest score, followed by the local community’s willingness and the supporting activities of the local government. The trend for agritourism development and the agritourism market was rated the lowest. Therefore, Binh Dinh has viable opportunities to encourage the growth of agritourism to improve farmers’ livelihoodsDu lịch nông nghiệp đem lại nhiều cơ hội cho phát triển kinh tế cũng như đa dạng hóa các loại hình du lịch và cải thiện đời sống sinh kế của người dân. Nghiên cứu sử dụng phương pháp phân tích thứ bậc (AHP) để tính các trọng số của các tiêu chí đánh giá tiềm năng phát triển du lịch nông nghiệp tại các huyện, thị xã phía bắc tỉnh Bình Định. Tiếp theo, kết quả mô hình hóa sơ đồ mạng cho thấy cả 4 địa phương An Lão, Hoài Ân, Phù Mỹ, thị xã Hoài Nhơn đều được đánh giá ở mức điểm cao về tiềm năng phát triển du lịch nông nghiệp trên các khía cạnh tài nguyên du lịch, xu hướng phát triển du lịch, sự ủng hộ của người dân địa phương và sự quan tâm của chính quyền địa phương. Tuy nhiên, yếu tố xu hướng phát triển thị trường du lịch nông nghiệp được đánh giá ở mức điểm thấp hơn. Điều này cũng xuất phát từ việc phát triển du lịch nông nghiệp tại các huyện, thị xã phía Bắc tỉnh Bình Định cũng mới bắt đầu nhận được sự quan tâm trong vài năm gần đây, số lượt khách tham quan các huyện, thị xã phía Bắc tỉnh Bình Định còn ít so với tiềm năng du lịch của địa bàn

Generic structures and linguistic features of TESOL master’s thesis acknowledgements written by Vietnamese postgraduates

Acknowledgements are a widely used genre in academic discourse to express gratitude towards various types of assistance and contribution of individuals and institutions, and they have been reported to be contextually and culturally interwoven. Despite a number of acknowledgement studies in various settings, little is known of how these texts are composed by EFL writers in Vietnam and whether or not the culture has any influence on the composition of acknowledgements as reported in previous studies of acknowledgements. Following Hyland’s (2004) and Hyland and Tse’s (2004) frameworks, this study investigates the generic structures and linguistic elements of acknowledgements in 202 TESOL master’s theses written by Vietnamese postgraduates. The findings were compared with those in the literature to explore cross-cultural variations in acknowledgement writing. Semi-structured interviews were also conducted with actual thesis writers. The results revealed that these writers generally followed Hyland’s (2004) three-tier structure of writing thesis acknowledgements, but they were frank and less reserved in expressing their gratitude than their Chinese-speaking counterparts. Moreover, socio-cultural expectations, personal dispositions, and individual writing styles mainly affected their move constructions, inclusions of acknowledgees and linguistic choices

An elementary proof of Euler formula using Cauchy's method

The use of Cauchy's method to prove Euler's well-known formula is an object of many controversies. The purpose of this paper is to prove that Cauchy's method applies for convex polyhedra and not only for them, but also for surfaces such as the torus, the projective plane, the Klein bottle and the pinched torus