Thermal annealing behaviour on electrical properties of Pd/Ru Schottky contacts on n-type GaN

We have investigated the electrical properties of Pd/Ru Schottky contacts on n-GaN as a function of annealing temperature by current-voltage (I-V) and capacitance-voltage (C-V) measurements. The Schottky barrier height of the as-deposited Pd/Ru contact is found to be 0.67 eV (I-V) and 0.79 eV (C-V), respectively. Measurements showed that the Schottky barrier height increased from 0.68 eV (I-V) and 0.80 eV (C-V) to 0.80 eV (I-V) and 0.96 eV (C-V) as the annealing temperature is varied from 200 °C to 300 °C. Upon annealing at 400 °C and 500 °C, the Schottky barrier height decreased to 0.73 eV (I-V) and 0.85 eV (C-V) and 0.72 eV (I-V) and 0.84 eV (C-V), respectively. It is noted that the barrier height further decreased to 0.59 eV (I-V) and 0.72 eV (C-V) when the contact is annealed at 600 °C. The change of Schottky barrier heights and ideality factors with annealing temperature may be due to the formation of interfacial compounds at the Ru/Pd/n-GaN interface. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2788

How Participatory is Participatory Irrigation Management (PIM)? A Study of Water User Associations (WUAs) in Andhra Pradesh

It is argued that the reason for the ills of irrigation management is the alienation of farmers from the process of planning and implementation. Often 'lack of political will' is identified as the main reason for the tardy progress in irrigation reforms at the state level. Andhra Pradesh has demonstrated the political will by initiating widespread irrigation reforms through legislation. This paper, based on the situation after six years of WUAs in existence, makes an attempt to provide a comprehensive view on the status and functioning of the Water Users' Associations in the State. It is argued that while substantial amounts of money were spent on the reform process, the money was used mainly for improving the ailing irrigation systems rather than strengthening the formal institutional structures. Though some benefits in terms of increased area under irrigation in canal systems and improved quality of irrigation is evident, the sustainability of these benefits is rather uncertain in the absence of efficient institutional structures. Despite the fact that WUAs are promoted as non-political institutions, 'elite capture' and political involvement dominate their functioning. And the present trend appears to be towards further politicization of these institutions. More importantly, even after six years of their existence devolution of powers to WUAs has not taken place, as most of the important functions like assessment, collection of water charges, sanctioning of works, etc., are still in the hands of the irrigation department. In the absence of devolution of powers the WUAs are aiming for political gains rather than improving the systems. It is argued that political will is a necessary but not a sufficient condition for making the WUAs autonomous and self-sufficient. Restructuring and reforming of the State irrigation departments and the bureaucracy is critical for effective and sustainable irrigation institutions.participatory, Irrigation Management, water, Andhra Pradesh

Cost of resource degradation externalities: A study of groundwater depletion in Andhra Pradesh

This paper looks in to the process of environmental degradation and the resultant externalities in the context of groundwater depletion in drought prone regions. The main objective here is to estimate the costs of groundwater depletion externalities and examine the costs and benefits from groundwater replenishing mechanisms in different ecological contexts. This study shows how groundwater exploitation in India is resulting in economic losses to individual farmers apart from ecological degradation. It is argued that policies towards strengthening the resource base (abatement mechanisms) and equitable distribution of the resource (property rights) would be beneficial, economically as well as ecologically. The cost-benefit comparison is in favour of investment in replenishment mechanisms such as irrigation tanks and percolation tanks. The situation of over extraction and the resultant environmental degradation is a consequence of lack of appropriate and adequate policies (policy failure) for managing the subsurface water resources. Hither to, groundwater policies (subsidised credit, power, etc) are in the nature of encouraging private initiatives in groundwater development. While these policies helped in promoting groundwater development in the regions where groundwater development was below potential, they have led to over exploitation of the resource in fragile resource regions. On the other hand, no attempts were made (at the policy level) to strengthen the natural resource base in terms of replenishing the water table. On the contrary, groundwater development is seen as a substitute for tanks, which are the main agents of replenishment.Environment, Degradation, Groundwater, Externalities, Costs, Andhra Pradesh, South India

Costs of Resource Degradation Externalities - A Study of Groundwater Depletion in Andhra Pradesh

This paper looks in to the process of environmental degradation and the resultant externalities in the context of groundwater depletion in drought prone regions. The main objective here is to estimate the costs of groundwater depletion externalities and examine the costs and benefits from groundwater replenishing mechanisms in different ecological contexts. This study shows how groundwater exploitation in India is resulting in economic losses to individual farmers apart from ecological degradation. It is argued that policies towards strengthening the resource base (abatement mechanisms) and equitable distribution of the resource (property rights) would be beneficial, economically as well as ecologically. The cost-benefit comparison is in favour of investment in replenishment mechanisms such as irrigation tanks and percolation tanks. The situation of over extraction and the resultant environmental degradation is a consequence of lack of appropriate and adequate policies (policy failure) for managing the subsurface water resources. Hither to, groundwater policies (subsidised credit, power, etc) are in the nature of encouraging private initiatives in groundwater development. While these policies helped in promoting groundwater development in the regions where groundwater development was below potential, they have led to over exploitation of the resource in fragile resource regions. On the other hand, no attempts were made (at the policy level) to strengthen the natural resource base in terms of replenishing the water table. On the contrary, groundwater development is seen as a substitute for tanks, which are the main agents of replenishment.Environment, Degradation, groundwater, externalities, Costs, Andhra

Sustaining Rural Livelihoods in Fragile Environments : Resource Endowments or Policy Interventions?

This paper primarily assesses the status of rural livelihoods in fragile environments with diverse resource endowments and policy interventions. The objective was to examine the effectiveness of resource enhancing policy interventions like watershed development in reducing resource endowment imbalances across villages and regions. Livelihood assessment was carried out using the sustainable rural livelihoods (SRL) framework in the fragile regions of Andhra Pradesh. Qualitative and quantitative approaches were used to assess the rural livelihoods covering all the 555 households in three sample villages. It is argued that resource endowments determine the level and dynamics of livelihoods at the household level rather than policy interventions per se. On the other hand, policy interventions, given the status and structure of the economy, only act as catalysts. Policies for strengthening the resource base are necessary but not sufficient to address the livelihood issues. In the present case it is shown that availability of water (irrigation) is more important than the recent policy interventions like watershed development for improving the livelihoods. Nevertheless, policy interventions towards human capital development (education, skills, etc) could be rewarding in the long run. Unless policies are directed towards bringing changes in natural resource endowments (especially water) at the household level, it is unlikely that the on going policy interventions would transform the rural livelihoods in the fragile environments.Rural livelihoods, resource endowments, watershed development, policy

Sustaining rural livelihoods in fragile environments: Resource endowments or policy interventions?

This paper primarily assesses the status of rural livelihoods in fragile environments with diverse resource endowments and policy interventions. The objective was to examine the effectiveness of resource enhancing policy interventions like watershed development in reducing resource endowment imbalances across villages and regions. Livelihood assessment was carried out using the sustainable rural livelihoods (SRL) framework in the fragile regions of Andhra Pradesh. Qualitative and quantitative approaches were used to assess the rural livelihoods covering all the 555 households in three sample villages.Rural livelihoods, resource endowments, watershed development, policy interventions, Andhra Pradesh