Dunfu Zhang

Dunfu Zhang


Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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9 March 2018 in Sustainability
Verified
Journal Article
Open access
PDF file
KRK. M. Atikur Rahman
K. M. Atikur Rahman
DZDunfu Zhang
Dunfu Zhang
The excessive use of inorganic fertilizers causes serious environmental degradation, resulting in lower crop yields in Bangladesh. Seventy percent of Bangladesh farmers practice traditional fertilizer broadcasting. In the 1960s, the Bangladesh state authority launched a ‘Grow More Food’ campaign to feed the country’s increasing population. Farmers were supplied with chemical fertilizers and pesticides at a subsidized price. Farmers increased the frequency of fertilizer applications to enhance yields. These practices are still used and have caused significant environmental degradation. In this study, we examined the effects of fertilizer broadcasting on excessive use of fertilizer and environmental risks. We collected data from 211 Bangladesh infield farmers in 2016. Respondents were interviewed using a semi-structured questionnaire. Data were analyzed by applying a binary logistic regression model to test the degree of effects between the testable variables. The study found that the effect of broadcasting on the excessive use of fertilizers is strongly significant, at 1%. It also found that younger farmers have a significant effect at 10% on the excessive use of fertilizers. Bangladesh policymakers can formulate policy on sustainable fertilizer management, introducing different placement methods on the basis of this finding. After that, the Directorate of Agricultural Extension (DAE) can carry out the policy at the field level.

28 October 2018 in Sustainability
Verified
Journal Article
Open access
PDF file
KRK. M. Atikur Rahman
K. M. Atikur Rahman
DZDunfu Zhang
Dunfu Zhang
This study estimates the factors affecting socially vulnerable groups’ demand for and accessibility levels to green public spaces in Dhaka City, Bangladesh. Dhaka is a high-density city with one of the lowest levels of green space per capita in the world. Dhaka has just 8.5% of tree-covered lands, while an ideal city requires at least 20% of green space. Urban public green space provides a healthy environment to city dwellers as well as ecological soundness. This study aims to examine the effects of population density and size of a community area (Thana) on the social demand for and accessibility to green parks. To determine the socially vulnerable group demand index, this study used demographic data from the National Population and Housing Census 2011 conducted by the Bangladesh Bureau of Statistics. This study used geographical data extracted from Google Earth Pro to measure accessibility levels, and additionally analyzed geographical data with ArcGIS 10.0 and Google Earth Pro. We drew radius circles using Free Map Tools to measure time-distance weighted scores from community areas to urban green spaces. The results show that the large population size of socially vulnerable groups creates very high demand at the score of 0.61 for urban green public parks and small-sized, high-density community areas generate very good accessibility at 2.01% to green public spaces. These findings are highly useful to policymakers, urban planners, landscape engineers, and city governments to make a compact city sustainable, inclusive, and resilient. Moreover, the notion of a “smart city” might be a smart solution in order to manage Dhaka Megacity sustainably in this modern technological age.

10 February 2023 in Journal of Asian and African Studies
Verified
Journal Article
Closed access
AAAlemayehu Anja
Alemayehu Anja
DZDunfu Zhang
Dunfu Zhang
This article examines the role that social capital plays in ensuring the survival of street vendors in Dilla Town, Southern Ethiopia. The study employed a qualitative research approach informed by a case study design. A purposive sampling technique was employed to select 35 street vendors. In-depth interviews, key informant interviews, and non-participant observations were used as data collection methods. The study revealed that street vendors rely on various forms of bonding, bridging, and linking social capital in their daily life. Such social capital helps them to secure accommodation and food, get suitable vending places, start and expand enterprises, save money, socialize, and maintain social ties. It also helps them to ensure their families’ well-being, mutual protection, and the security of goods. Thus, the study recommends that government agencies and non-governmental organizations should work together to help street vendors through their social networks to improve their socioeconomic conditions.

24 December 2021 in Marine Georesources & Geotechnology
Verified
Journal Article
Closed access
BZBo-nan Zhang
Bo-nan Zhang
DZDunfu Zhang
Dunfu Zhang
BZBo Zhang
Bo Zhang
HBHan Bo
Han Bo
Rock-socketed pile is one of the important foundation forms for offshore wind turbines, however, the construction of rock-socketed piles is very difficult. In this work, we propose to use hydraulic fracturing to pre-crack the rock foundation seabed around the piles to assist the construction of rock-socketed piles. Understanding the propagation mechanism of hydraulic fractures is the theoretical basis for hydraulic fracturing of rock seabed. Using mortar specimens containing single internal cracks and corresponding numerical simulations, hydraulic fracturing tests were carried out to study the influences of pre-existing crack characteristics and in situ stress on hydraulic fracture propagation behavior. The mortar specimens showed a tensile-shear failure mode under confining stress in hydraulic fracturing tests, and a macro-fracture penetrated the upper and lower ends of the specimens. Quantitative analysis of hydraulic fracture propagation behavior shows that under the comprehensive influences of the pre-existing crack angle and the stress, it is relatively easy to obtain good engineering results by selecting the pre-existing crack dip angle of 45°∼60° for directional hydraulic fracturing, and the increase of in-situ stress will improve the stability and deflection capacity of the cracks in the seabed.

8 August 2023 in Journal of Asian and African Studies
Verified
Journal Article
Closed access
AAAlemayehu Anja
Alemayehu Anja
DZDunfu Zhang
Dunfu Zhang
This article investigates the perspectives and experiences of street vendors in Dilla Town, Southern Ethiopia, focusing on their motivations for engaging in business and social mobility. The study used a descriptive survey design and gathered data through a questionnaire survey, in-depth interviews, and non-participant observations. A time-location sampling technique was applied to select 250 vendors, and an additional 15 were interviewed using a convenience sampling procedure. The data were analyzed using a combination of quantitative and qualitative data analysis techniques. The results revealed that vendors chose street vending due to unemployment, the aspiration for unbridled autonomy, low entry barriers, minimal initial investment requirements, social connections, and the necessity to bolster meager salaries. Most street vendors reported a better standard of living since embarking on their vending venture. The study recommends that local government authorities should acknowledge the socio-economic significance of street vending business for economically disadvantaged urban populations.

13 November 2017 in Preprints.org
Verified
Preprint
Open access
PDF file
KRK. M. Atikur Rahman
K. M. Atikur Rahman
DZDunfu Zhang
Dunfu Zhang
The study focuses on how socio-economic and demographic indicators affect fertilization sustainability (excessive amount of fertilization). Principally we aim to examine the significance magnitude of the effects of three socio-demographic variables such as traditional way of fertilization, rental land farming, and farmers’ younger age on over-fertilization in Bangladesh and other developing countries. In 1960s, Bangladesh state authority launched a campaign ‘Grow more Food’ to feed huge numbers of population and thus the farmers are provided chemical fertilizers and pesticides at a subsidized low price. Farmers began to use huge amount of fertilizers for gaining high yields and continued it to present causing environmental woes a lot. We interview (face-to-face, focus group discussion, and phone interview) 210 Bangladesh farmers in 2016 by semi-structured questionnaire. Data has been analyzed using General Linear Model (GLM) in Univariate Analysis of Variance. The study found the effect of traditional way of fertilization on excessive amount of fertilization is strongly significant at 1% level. Apart from, rental land farming and farmers’ younger age have a significant influence on over- fertilization; though their significance level (5% and 10% respectively) is quasi-strong. Policy makers can be able to formulate fertilizer policy on the basis of these findings.