Nghiên cứu, đánh giá tác động của các yếu tố khí hậu đến năng suất lúa tại tỉnh Quảng Bình







Title: Nghiên cứu, đánh giá tác động của các yếu tố khí hậu đến năng suất lúa tại tỉnh Quảng Bình
Authors: Nguyễn Lê Hà Phương
Keywords: Lúa, Quảng Bình
Issue Date: 2017
Publisher: H.: Khoa các khoa học liên ngành
Description: 86 tr.
URI: http://repository.vnu.edu.vn/handle/VNU_123/54478
Appears in Collections:SGS - Master Theses

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Torsional buckling and post-buckling behavior of eccentrically stiffened functionally graded toroidal shell segments surrounded by an elastic medium

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Bedeutungswandel in der deutschen spracheam beispiel der modalverben = Biến đổi nghĩa trong tiếng Đức dựa trên ví dụ của động từ tình thái. Luận văn ThS. Ngôn ngữ học: 60 22 02 05

Title:  Bedeutungswandel in der deutschen spracheam beispiel der modalverben = Biến đổi nghĩa trong tiếng Đức dựa trên ví dụ của động từ tình thái. Luận văn ThS. Ngôn ngữ học: 60 22 02 05 Authors:  Jaiser, Gerhard, người hướng dẫn Bùi, Linh Hà Issue Date:  2014 Publisher:  ĐHNN Abstract:  Luận văn ThS. Ngôn ngữ Đức -- Trường Đại học Ngoại ngữ. Đại học Quốc gia Hà Nội, 2014 Electronic Resources URI:  http://repository.vnu.edu.vn/handle/VNU_123/40649 Appears in Collections: ULIS - Master Theses
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Nonlinear buckling of higher deformable S-FGM thick circular cylindrical shells with metal-ceramic-metal layers surrounded on elastic foundations in thermal environment

An analytical approach on the nonlinear response of thick functionally graded circular cylindrical shells with temperature independent material property surrounded on elastic foundations subjected to mechanical and thermal loads is presented. Material properties are graded in the thickness direction according to a Sigmoid power law distribution in terms of the volume fractions of constituents (S-FGM). The formulations are based on the third order shear deformation shell theory taking into account von Karman nonlinearity, initial geometrical imperfection and Pasternak type elastic foundation. By applying Galerkin method and using stress function, explicit relations of thermal load-deflection curves of the S-FGM shells are determined. Detailed parametric studies are carried out to investigate effects of volume fraction index, material properties and geometrical shapes, axial compressions and thermal load, foundation stiffness and imperfection on nonlinear buckling behaviors ...
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