Đinh Ngọc Quý * , Phạm Hải Đăng Đỗ Hồng Diễm

* Tác giả liên hệ (dnquy@ctu.edu.vn)

Abstract

In this paper, the aim is to provide a vector version of Ekeland’s theorem related to equilibrium problems when dealing with bifunctions defined on complete metric spaces and with values in Hausdorff locally convex spaces ordered by closed convex pointed cones. To prove this principle, a weak notion of continuity of a vector-valued function is considered, and some of its properties are presented. Via the vector Ekelands principle, some existence theorems on solutions for vector equilibria are proved in compact domains.
Keywords: Ekeland's variational principle, equilibrium problem, relaxed semicontinuity

Tóm tắt

Trong bài báo này, nguyên lý biến phân Ekeland được mở rộng cho hàm hai biến véctơ từ không gian mêtric đủ vào không gian Hausdorff lồi địa phương được trang bị thứ tự bởi một nón lồi đóng có đỉnh. Dựa vào nguyên lý biến phân Ekeland để thiết lập điều kiện đủ cho tồn tại nghiệm của bài toán cân bằng véctơ trong trường hợp tập xác định là compact.
Từ khóa: Bài toán cân bằng, nguyên lý biến phân Ekeland, tính nửa liên tục giảm nhẹ

Article Details

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