On alternative theorems and necessary conditions for efficiency

In this paper, we establish theorems of the alternative for a system described by inequalities, equalities and an inclusion, which are generalizations of Tucker's classical theorem of the alternative, and develop Kuhn-Tucker necessary conditions for efficiency to mathematical programs in normed spaces involving inequality, equality and set constraints with positive Lagrange multipliers of all the components of objective functions.Theorem of the alternative, Kuhn-Tucker necessary condition, constraint qualification.

ON NECESSARY CONDITIONS FOR EFFICIENCY IN DIRECTIONALLY DIFFERENTIABLE OPTIMIZATION PROBLEMS

This paper deals with multiobjective programming problems with in- equality, equality and set constraints involving Dini or Hadamard differentiable func- tions. A theorem of the alternative of Tucker type is established, and from which Kuhn-Tucker necessary conditions for local Pareto minima with positive Lagrange multipliers associated with all the components of objective functions are derived.Theorem of the alternative, Kuhn-Tucker necessary conditions, direc- tionally differentiable functions.

Economic value of coral reef and management effectiveness in Trao Reef locally managed marine reserve

Trao Reef Locally Managed Marine Reserve was established in 2001 to protect coral reef being under threat because of human activities. However, the economic value of coral reef represents an important sight to help local people and resource managers in using and managing the resource effectively in the marine reserve has not been seen. By using financial analysis to calculate producer surplus of resource users, this study evaluated the direct use value consisting of fishery and aquaculture values of coral reef in the marine reserve. The findings show that the direct use value of coral reef is US$ 207,819 in which aquaculture is an important contribution. This study also investigated the evaluation of effectiveness of the marine reserve management under the context of community based management approach by contrasting with Nha Trang Bay MPA management which follows top-down management approach. The results show that community in Trao Reef marine has higher awareness, higher compliance, and higher participation to the marine reserve management. These indicators imply that Trao Reef management is performing better than Nha Trang Bay MPA management

On constraint qualifications with generalized convexity and optimality conditions

This paper deals with a multiobjective programming problem involving both equality constraints in infinite dimensional spaces. It is shown that some constraint qualifications together with a condition of interior points are sufficient conditions for the invexity of constraint maps with respect to the same scale map. Under a new constraint qualification which involves an invexity condition and a generalized Slater condition a Kuhn-Tucker necessary condition is established.Invexity, scale, constraint qualification, nearly S-convelike mapping.

ENTREPREURIAL SELF-EFFICACY AND THE LIKELIHOOD OF BEING SELF-EMPLOYED – A COMPARISON OF URBAN AND RURAL AREAS IN VIETNAM

A large body of entrepreneurship research has focused on the relationship between entrepreneurial self-efficacy and start-up activity. Yet, little is known about how the interplay of these mechanisms is moderated by informal institutional conditions (e.g., social traits in rural and urban regions). Particularly, Vietnam, a country with a socialist-oriented market economy, has emerged as one of the world’s most entrepreneurial countries. This study examines how the effects of individuals’ entrepreneurial self-efficacy on being self-employed are contingent on institutional environments (e.g., rural and urban areas). Statistical analyses of 2013 to 2015 data from the Global Entrepreneurship Monitor (GEM) project for Vietnam provide empirical evidences that entrepreneurial self-efficacy is significantly and positively associated with being self-employed, and that this effect is more pronounced for individuals in rural than those in urban areas. Moreover, the findings show that people in rural Vietnam are more willing to be self-employed than their peers in urban areas. This difference is explained by the distinct impact of the informal institutional variable, entrepreneurial self-efficacy (e.g., the knowledge, skills, and experience required to start a new business) that individuals living in rural areas may gain from entrepreneurship promotion and start-up programs supported by the Vietnamese leadership. Our findings have implications for national entrepreneurship programs and financial support for start-up projects in rural areas

Factors Affecting the Choice of Supermarket for Shopping by Consumers in Hanoi Capital in Vietnam

In recent years, the Vietnam's economy has been growing, the demand for shopping and consumption of Vietnamese people has been sharply increased. The boom of branded and prestigious supermarket chains in the market such as Big C, Mobile World, Vinmart, or new retailers entering the organized retail market (supermarkets) in Vietnam has partly met the shopping needs of Vietnamese people. The authors select the scope of the study is Hanoi capital to identify and measure the factors that influence consumers' decisions to choose a shopping supermarket. Through qualitative and quantitative analysis, the research results show that there are 07 factors that influence the consumer's decision of choosing supermarkets to buy goods in Hanoi capital, which are the goods, prices, Convenience, reliability, supermarket staff, communication marketing and shopping environment. In particular, goods have the biggest influence on the consumer's decision choosing the supermarkets to buy in Hanoi, Vietnams. Keywords: Consumers; Supermarket; Consumer behavior DOI: 10.7176/EJBM/12-3-06 Publication date: January 31st 202

INFLUENCE OF PALEOGEOGRAPHICAL CONDITIONS ON CHEMICAL COMPONENTS OF GROUND WATER IN THE SOUTHERN PLAIN, VIETNAM

Joint Research on Environmental Science and Technology for the Eart