Unsteady mixed convective boundary layer flow of viscous incompressible fluid along isothermal horizontal plate is analyzed through Similarity Solutions. The governing partial differential equations are transformed in...Unsteady mixed convective boundary layer flow of viscous incompressible fluid along isothermal horizontal plate is analyzed through Similarity Solutions. The governing partial differential equations are transformed into ordinary differential equations using the similarity transformation and solved numerically along with shooting technique. The flow field for the fluid velocity, temperature and concentration at the plate surface are significantly influenced by the governing parameters such as unsteadiness parameter, permeability parameter, Prandtl number, Schmidt number and the other driving parameters. The results show that both fluid velocity and temperature decrease but no significant effect on concentration for the increasing values of Prandtl number. It is also exposed that velocity and concentration is higher at lower Schmidt number for low Prandtl fluid. Finally, the dependency of the Skin-friction co-efficient, Nusselt number and Sherwood number, which are of physical interest, are also illustrated in tabular form for the governing parameters.展开更多
Socio-economic conditions of farmers, especially in the coastal region in Bangladesh, have been severely affected because of climate change. This study was focused on analyzing the farmers’ perception of climate chan...Socio-economic conditions of farmers, especially in the coastal region in Bangladesh, have been severely affected because of climate change. This study was focused on analyzing the farmers’ perception of climate change by examining three vital issues: (1) description of the socioeconomic characteristics of farmers;(2) reporting on the perception of farmers experiences with climatic change;and (3) identification of the socio-economic factors associated with farmers’ perception of climate change. The study area encompasses three villages within the coastal region (Sathkhira district) of Bangladesh, a geographic region where climate change literature has highlighted as prone to accelerated degradation. A logit model, along with weighted indexes for ranking and descriptive statistics, was used to analyze the result of 100 farmers surveyed by questionnaire. We found that the majority of the farmers (88%) perceived changes in climatic conditions. Almost all farmers indicated increases in temperature, droughts, floods, cyclones, salinity level and decreasing rainfall over the last 20 years. The logit model explained that out of the nine factors surveyed;education, family size, farm size, family income, farming experiences and training received were significantly related and influential factors to perception of climate change. Therefore, government and non-governmental organizations are recommended to push forward with interventions, especially focusing on identified factors, in order to strengthen the farmers’ capacity to battle against climate change effects.展开更多
The emergence of NGOs represents an organized response by civil society especially in those areas in which the state has either failed to reach or done so inadequately. NGOs have been taking a number of steps to promo...The emergence of NGOs represents an organized response by civil society especially in those areas in which the state has either failed to reach or done so inadequately. NGOs have been taking a number of steps to promote discussion and debate about climate change issues. The study was conducted to determine the role of a coastal NGO named Speed Trust in attaining resilience in response to climate change in coastal region;viz. Kalapara sub-district under Patuakhali district. The sample size of the study was 80 respondents. The study followed a mixed-method of research design. Both structured and semi-structured questionnaires were prepared for collecting quantitative and qualitative data from the respondent. The empirical data for the study were collected through personal interviewing of the respondents. The findings of the study revealed that the role of Speed Trust in attaining climate resilience of the study area was varied with the change of aspects of climate resilience. It also indicated that majority (80 percent) of the respondents perceived the idea that Speed Trust is playing moderate to highly effective role in attaining climate resilience. While only 1.2 percent had perceived as poor role in attaining resilience in response to climate change. Correlation analysis indicated that among the selected socio-economic characteristics, respondent’s education, organizational participation, training on climate resilience, consequence due to climate change and participation in climate resilience program showed positive and significant relationship with the role of Speed Trust in response to climate resilience. Step-wise multiple regression analysis explored that amongst five variables, three independent variables finally entered into the model and the contribution factors are: participation, training, and organizational participation. They are jointly accounted for 62.2 percent of the total variation with perceived role of Speed Trust in attaining climate resilience. It was also established that the absolute majority (100 percent) of the respondents had to face low to medium level problems in getting Sped Trust’s services on climate change issues.展开更多
Similarity solution of unsteady convective boundary layer flow along isothermal vertical plate with porous medium is analyzed. The plate surface is reactive with the fluid and generates inert specie which diffuses ins...Similarity solution of unsteady convective boundary layer flow along isothermal vertical plate with porous medium is analyzed. The plate surface is reactive with the fluid and generates inert specie which diffuses inside the boundary. The flux of the specie at the plate is proportional to specie concentration at the plate. The governing equations of continuity, momentum, energy and specie diffusion are transformed into ordinary differential equation by using the similarity transformation and solved numerically by using free parameter method along with shooting technique. The dimensionless velocity, temperature and concentration profiles are obtained and presented through figures for different parameters entering into the problem. The local Skin-friction co-efficient, Nusselt number and Sherwood number at the plate for physical interest are also discussed through tables.展开更多
文摘Unsteady mixed convective boundary layer flow of viscous incompressible fluid along isothermal horizontal plate is analyzed through Similarity Solutions. The governing partial differential equations are transformed into ordinary differential equations using the similarity transformation and solved numerically along with shooting technique. The flow field for the fluid velocity, temperature and concentration at the plate surface are significantly influenced by the governing parameters such as unsteadiness parameter, permeability parameter, Prandtl number, Schmidt number and the other driving parameters. The results show that both fluid velocity and temperature decrease but no significant effect on concentration for the increasing values of Prandtl number. It is also exposed that velocity and concentration is higher at lower Schmidt number for low Prandtl fluid. Finally, the dependency of the Skin-friction co-efficient, Nusselt number and Sherwood number, which are of physical interest, are also illustrated in tabular form for the governing parameters.
文摘Socio-economic conditions of farmers, especially in the coastal region in Bangladesh, have been severely affected because of climate change. This study was focused on analyzing the farmers’ perception of climate change by examining three vital issues: (1) description of the socioeconomic characteristics of farmers;(2) reporting on the perception of farmers experiences with climatic change;and (3) identification of the socio-economic factors associated with farmers’ perception of climate change. The study area encompasses three villages within the coastal region (Sathkhira district) of Bangladesh, a geographic region where climate change literature has highlighted as prone to accelerated degradation. A logit model, along with weighted indexes for ranking and descriptive statistics, was used to analyze the result of 100 farmers surveyed by questionnaire. We found that the majority of the farmers (88%) perceived changes in climatic conditions. Almost all farmers indicated increases in temperature, droughts, floods, cyclones, salinity level and decreasing rainfall over the last 20 years. The logit model explained that out of the nine factors surveyed;education, family size, farm size, family income, farming experiences and training received were significantly related and influential factors to perception of climate change. Therefore, government and non-governmental organizations are recommended to push forward with interventions, especially focusing on identified factors, in order to strengthen the farmers’ capacity to battle against climate change effects.
文摘The emergence of NGOs represents an organized response by civil society especially in those areas in which the state has either failed to reach or done so inadequately. NGOs have been taking a number of steps to promote discussion and debate about climate change issues. The study was conducted to determine the role of a coastal NGO named Speed Trust in attaining resilience in response to climate change in coastal region;viz. Kalapara sub-district under Patuakhali district. The sample size of the study was 80 respondents. The study followed a mixed-method of research design. Both structured and semi-structured questionnaires were prepared for collecting quantitative and qualitative data from the respondent. The empirical data for the study were collected through personal interviewing of the respondents. The findings of the study revealed that the role of Speed Trust in attaining climate resilience of the study area was varied with the change of aspects of climate resilience. It also indicated that majority (80 percent) of the respondents perceived the idea that Speed Trust is playing moderate to highly effective role in attaining climate resilience. While only 1.2 percent had perceived as poor role in attaining resilience in response to climate change. Correlation analysis indicated that among the selected socio-economic characteristics, respondent’s education, organizational participation, training on climate resilience, consequence due to climate change and participation in climate resilience program showed positive and significant relationship with the role of Speed Trust in response to climate resilience. Step-wise multiple regression analysis explored that amongst five variables, three independent variables finally entered into the model and the contribution factors are: participation, training, and organizational participation. They are jointly accounted for 62.2 percent of the total variation with perceived role of Speed Trust in attaining climate resilience. It was also established that the absolute majority (100 percent) of the respondents had to face low to medium level problems in getting Sped Trust’s services on climate change issues.
文摘Similarity solution of unsteady convective boundary layer flow along isothermal vertical plate with porous medium is analyzed. The plate surface is reactive with the fluid and generates inert specie which diffuses inside the boundary. The flux of the specie at the plate is proportional to specie concentration at the plate. The governing equations of continuity, momentum, energy and specie diffusion are transformed into ordinary differential equation by using the similarity transformation and solved numerically by using free parameter method along with shooting technique. The dimensionless velocity, temperature and concentration profiles are obtained and presented through figures for different parameters entering into the problem. The local Skin-friction co-efficient, Nusselt number and Sherwood number at the plate for physical interest are also discussed through tables.
