A new approach for investigating corrugated laminated composite plates of wave form

Corrugated plates of wave form made of isotropic elastic material were considered as flat orthotropic plates with corresponding orthotropic constants determined empirically by the Seydel’s technique. In some recent researches the extension of this technique was given for corrugated laminated composite plates. In the present paper a new approach for investigating corrugated composite plate of wave form is proposed, regarding this plates as a combination of parts of shallow cylindrical shells with alternative curvatures. It reduces to no use of Seydel’s empirical formulas and sufficiently apply to composite plates. Based on this approach governing equations of corrugated laminated composite plate of wave form are developed and application to the non-linear stability problem of this plate is considered. Obtained results are compared with those of Seydel’s technique

Non-linear analysis on stability of corrugated cross-ply laminated composite plates

In the present paper the governing equations for corrugated cross-ply laminated composite plates in the form of a sine wave are developed based on the Kirchoff-Love's theory and the extension of Seydel's technique. By using Bubnov-Galerkin method approximated analytical solutions to the non-linear stability problem of corrugated laminated composite plates subjected to biaxial loads are investigated. The post buckling load-deflection curve of corrugated plates and analytical expressions of the upper and lower buckling loads are presented. The effectiveness of corrugated plates in enhancing the stability compared with corresponding fiat plates is given

Focus group

Qualitative research, questionnaires, opinions, teamwork skill

Questionnaire design

The primary survey, primary data, questionnaire method, model

Chi trả tự nguyện cho hoạt động xử lý rác thải sinh hoạt của người dân ở miền Bắc Việt Nam

Nghiên cứu này đánh giá mức độ nhận thức của người dân của khu vực miền Bắc Việt Nam về tình trạng ô nhiễm rác thải sinh hoạt (RTSH), sự sẵn lòng chi trả cho việc xử lý RTSH trong cả khu vực thành thị và nông thôn. Trong bối cảnh của đại dịch Covid-19, nhóm nghiên cứu đã kết hợp phương pháp phỏng vấn trực tiếp và online để khảo sát 502 hộ gia đình tại 8 tỉnh/thành phố ở khu vực miền Bắc Việt Nam. Kết quả cho thấy 71,5% người được khảo sát đã nhận thức được vấn đề ô nhiễm môi trường do rác thải sinh hoạt gây ra, 83,07% người dân được khảo sát sẵn sàng chi trả tự nguyện (WTP) cho các hoạt động xử lý rác thải sinh hoạt tại khu vực sinh sống với giá trị trung bình được ước tính từ mô hình dao động từ 154.000VND đến 155.000VND đồng/tháng/hộ gia đình. Kết quả phân tích mô hình cho thấy người dân khu vực nông thôn có xu hướng sẵn sàng chi trả tự nguyện cho quỹ xử lý rác thải cao hơn người dân sống ở thành thị. Bên cạnh đó, những công dân có trình độ học vấn, nhận thức cao thì sẵn sàng chi trả hơn, những người phụ nữ chăm lo công việc nội trợ trong gia đình sẽ quan tâm hơn đến vấn đề xử lý rác thải sinh hoạt và sẵn sàng chi trả cho vấn đề này. Kết quả nghiên cứu này gợi mở một số giải pháp chính sách nhằm giảm thiểu ô nhiễm rác thải, thúc đẩy hợp tác công tư trong lĩnh vực quản lý và bảo vệ môi trường ở Việt Nam trong thời gian tới

Government pandemic policies associated with Vaccine Fund and Vaccine Diplomacy in response to COVID-19: A critical study of the Vietnamese experience

Vaccination, governmental policies, vaccine fund, Vietna

Household-Level Strategies to Tackle Plastic Waste Pollution in a Transitional Country

As one of the world’s fastest-growing economies, Vietnam is tackling environmental pollution, particularly plastic waste. This study contributes to the literature on environmental culture and practical solutions by better understanding households’ behaviours and motivations for (i) sorting waste, (ii) contributing to the environmental fund and (iii) relocating. The questionnaire-based interview method was used to randomly collect information from 730 households in 25 provinces in Vietnam during February 2022. Bayesian regression models, coupled with the mindsponge mechanism, were applied to analyse the data. The results showed that people’s strategies and responses to plastic waste pollution vary: 38.63% of respondents were sorting waste at home, 74.25% of households agreed to contribute to the environmental fund, and 23.56% had a plan to relocate for a better living place. The households’ strategies and intentions were driven by several structural and contextual factors such as age of household head, income, care about the environment, and the perceived effects of polluted waste. More importantly, communication was a robust variable in sorting waste decisions, which suggested that better communication would help increase people’s awareness and real actions in reducing plastic waste and ultimately improving the environment. These findings will benefit the ongoing green economy, circular economy, and green growth transition toward more sustainable development, particularly in developing and fast-population-growing countries

Farmers’ livelihood strategies and perceived constraints from poor and non-poor households: A dataset from a field survey in Nghe An, Vietnam

ABSTRACT: The first Sustainable Development Goals (SDGs) of The United Nations aims to “end poverty in all its forms everywhere”. Its seven associated targets aim, among others, to eradicate extreme poverty for all people everywhere. In Vietnam, poverty eradication in ethnic minorities and mountainous areas are among the top priorities. This study aims to learn about farmers’ livelihoods associated with perceived difficulties in Chau Thai Commune, Nghe An Province, a rural mountainous area in Vietnam. A random sampling technique and a face-to-face interview method were employed to conduct a field survey in the region in 2018. The dataset collected from 215 households shows that Chau Thai Commune's livelihood largely depends on agriculture and forestry. Plantation forest and livestock are major sources of farmers’ income while forestland accounts for over 90% of households’ land. Besides, the disparity in livelihood in areas such as forestland, labor and income between the poor and non-poor households is reported. This primary data could be useful for scholars who want to conduct a further in-depth study and or experts, policymakers who work in Vietnam's ‘New Rural Development’ program to devise a better rural livelihood -improvement policy for farmers, particularly the poor in the uplands of Vietnam and beyond