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Using a pump in reverse mode as a hydraulic turbine remains an alternative for hydropower generation in meeting energy needs, especially for the provision of electricity to remote and rural settlements. The primary challenge with small hydroelectric systems is attributed to the high price of smaller size hydraulic turbines. A specific commercial pump model, with a flow rate of 12.5 m3/h, head 32 m, pressure side diameter of 50 mm, impeller out, and inlet diameters of 160 mm and 6 mm, respectively, was chosen for this research. This research aimed to investigate a pump’s flow characteristics as a turbine to help select a suitable pump to be used as a turbine for micro- or small hydropower construction. Numerical methodologies have been adopted to contribute to the thoughtful knowledge of pressure and velocity distribution in the pump turbine performance. In this study, the unsteady flow relations amongst the rotating impeller and stationary volute of the centrifugal pump made up four blades and four splitters. Intermittent simulation results of pressure and velocity flow characteristics were studied considering diverse impeller suction angles. The study was conducted by considering a wide range of rotational speeds starting from 750 rpm to 3250 rpm. From the results, it was found that PAT operation was improved when operated at low speeds compared to high-speed operation. Thus, speeds between 1500 rpm and 2000 rpm were suitable for PAT performance. This research helps to realize the unsteady flow physiognomies, which provide information for future research on PAT. This study makes useful facts available which could be helpful for the pump turbine development. Future studies should focus on cost analysis and emission generation in energy generation.

Energy contributes significantly in almost all aspects of human life as well as economic activities and plays a crucial role in the infrastructural development of a county to alleviate poverty. Generating energy from a renewable source such as small hydropower through the application of pump operating as a turbine mode called Pump as Turbine is one of the best alternatives to provide clean and inexpensive energy. Using Pump as Turbine helps in generating reasonably priced hydroelectric power for communities in underdeveloped counties. This study investigates the effects of internal flow behaviour and performance of Pump as Turbine under different rotational speed and flow rate. The rotational speed is an essential physical parameter as it affects the Pump as Turbine operation. A model-specific speed centrifugal pump model with head 32 (m), flow rate of 12.5 (m3/h) and the rotational speed of 2900 rpm, has been selected for the study. Numerical simulations have been conducted using the k-ω turbulence model to solve three-dimensional (3D) equations. The pump mode experimental data were used to confirm the results for better analysis. The results predicted that vortex and turbulent kinetic energy increase per rotational speed increase. Also, at the higher rotational speed, very high recirculation of flow is detected at the blade suction chamber, although the pressure side has a smooth flow. This study provides beneficial information which will serve as a reference to help improve PAT performance along with selecting PAT for a small hydropower site. Future works will consider the impact of blade thickness and cavitation in Pump as Turbine.

Access to consistent and clean energy is a key challenge faced by several countries globally; especially in Asian and African countries. Most of the communities within these and other regions in the world are faced with continuous energy crisis, causing most of these economies to cripple. It is estimated that billions of people worldwide are living without access to clean and reliable source of energy. Renewable energy is the biggest source of energy and it characterizes the basis to steer the energy system in the direction of sustainability and supply security. Several countries globally are blessed with rich renewable energy resources that have not been fully developed. These renewable resources have the potentials to change the status quo of power generation and consumption in these countries. In this study, the status of renewable energy generation and storage was identified and discussed. A specific centrifugal pump model with radial volute and 6 impeller blades having inlet and outlet diameter of 104 mm and 160 mm respectively. The operational parameter of the head is 16 m, flow rate is 12.5 m3/h, rotational speed is 2900 r/min and efficiency is 56% were selected to carry out numerical simulations in the study. Using the centrifugal pump to operate as turbine (PAT), is one of the best alternatives for small and micro hydro generation since it helps in meeting energy needs. Furthermore, it can also help improve economic growth due to its cheapest source of power generation as well as providing sustainable energy source that will create more employment opportunities to improve the socio-economic environments of the people. Moreover, PAT method are also advantageous because of its low cost in acquisition and maintenance. The characteristics of PAT have been discussed numerically to analyze pressure and velocity distribution at different rotational speeds. The study concludes that PAT is the best alternative for energy generation.

Synthesizing theories of ethical leadership, psychological climate, pro-environmental behavior, and gender, first, we proposed and tested a model linking supervisors’ ethical leadership and organizational environmental citizenship behavior via a green psychological climate. Then, we tested the moderating effect of gender on the indirect (via a green psychological environment) relationship between supervisors’ ethical leadership and organizational environmental citizenship behavior. Time-lagged (three waves, 2 months apart) survey data were collected from 447 employees in various manufacturing and service sector firms operating in China. Data were analyzed using structural equation modeling, bootstrapping, and multigroup techniques to test the hypothesized relationships. The results showed a positive relationship between employee ratings of supervisors’ ethical leadership and organizational environmental citizenship behavior. Moreover, a green psychological climate mediates the relationship between supervisors’ ethical leadership and organizational environmental citizenship behavior. Importantly, the multigroup analysis revealed that gender moderates the indirect relationship (via green psychological climate) between supervisors’ ethical leadership and organizational environmental citizenship behavior. The study carries useful practical implications for policymakers and managers concerned about environmental sustainability.

Energy contributes greatly to every aspect of life and other activities, and is the main source of economic development of any country. Globally, the demand for electrical power has increased in recent times, causing a major increase in the price of various fuels. Energy production from various renewable and non-renewable resources is not new. However, its impact on the environment is a major concern. Several power plants from large hydro, wind, thermal and others are being used for energy generation, nevertheless the depletion of the environment is the major global concern. The challenges posed to the environment need to be tackled to protect our environment. This study evaluates the state of energy generation and distribution, and its potential environmental impacts on biodiversity, climate change, aquatic life, land use, emission generation, etc. We also propose some environmental management strategies that can help overcome these challenges.

Ecological security is gaining importance for its role in human development, as traditional risk factors are being increasingly replaced by threats such as ecological and environmental changes. Taking the example of Xiamen estuary, a typical estuary in southern China, our research focused on the problems related to ecological security, caused by the degradation of ecosystem service and function. We propose an evaluation index system for assessing the ecological services, and standardize ways to determine the evaluation standards and weights. The results show that the ecological security index for Xiamen estuary is 57.1, indicating a “warning” state. This implies that the ecosystem there has been damaged to some degree, and its systematic structure is deteriorating. Twelve indices showed a score below 60, four of which belong to the category of supply services. The study shows that there are some problems associated with the ecological services in Xiamen estuary. The indices that were considered as unsecure include fish density, marine trophic level, primary productivity of water bodies, alien species invasion risk, and species diversity. We conclude that these problems are mainly caused by human activities such as over-fishing, reclamations, and industrial and agricultural pollution.

This paper analyzed how consumer brand loyalty influences brand remanufacturers’ market strategy when independent remanufacturers (IRs) enter the market and when they do not. The authors developed ...

This article attempts to explain the factors that affect the board’s behavior when it comes to enhancing internal controls in financial institutions, particularly rural banks. The variables examined in this study are not different from the traditional determinants of board effectiveness or internal controls, but except that between all the five variables measured four are technically board characteristics while one relates directly to internal controls. A total of 459 valid structured questionnaire were analyzed based on the feedback gathered from various banks where employees, management and board members shared their views on the factors that would influence the board’s posture to enhance good governance and internal controls. The outcome of the study provided a convincing evidence that, internal audit, external consultancy and the audit committee are dominant determinants of internal control and good governance. Subsequent, examinations using the R square also confirms accuracy of predictions recorded in the principal component analysis. Further studies may analysis the size of the board relative to the increasing functions of ensuring compliance, independence and strategic decisions. This analysis is based on an African institutional context, but could be a universal tool.

Internal control is relevant in every business establishment, though its presence may not be a guarantee that fraud and corporate scandals would cease to occur. From the rural banking communities in Ghana, this study examines the significance of internal control element on the performance of elected rural banks. The statistical analysis and inferential judgment is based on the responses gathered from 650 bank employees on the functioning of internal controls. Based on the quantitative results and analysis, the study found a highly significant relationship between internal controls and performance of banks with respect to the principles prescribed by the Committee of Sponsoring Organization of the Treadway Commission framework –COSO. There exist a very strong internal control systems in the rural banks of Ghana, however monitoring, control activities and issues of corporate governance need to be addressed.

When manufacturer motivates retailer groups to increase sales efforts with a linear transfer payment contract, we assume that retailers concern about fairness and the channel structure which retailer access to information corresponds to the small-world network, and built a multi-agent model to mainly observe the impact of small-world network characteristics on the incentive effects. Experimental results show that the greater probability of replacement objects, the lower manufacturer's profit and products sales. The retailer gets very small amount of other retailers related information will have a huge negative impact on incentive effects, if the number of objects in comparison achieves a certain number, the manufacturers profit and products sales will not be affected to a large extent.

As the telecommunications market matures, the demand for telecommunications services to the users is fast-growing, and the telecom operators are rapidly building to change the focus from the network to the business operations, business development strategy from the past to focus on product, now “customer needs first.” Against this background, a new management philosophy based on information technologies — customer relationship management (CRM) more and more important. Based on the research and analysis of large amounts of data, combined with the actual situation of China’s telecommunications industry, and based on theoretical knowledge of CRM, discussed the application and the problems of CRM in the telecommunications industry, and made a series of measures and proposals, and we will tap the great potential of the telecommunications industry relying on the CRM.

With the rapid development of the information technology and continues improving of net economy, modern manufacturing enterprises have gradually changed their business model from the traditional into Internet-based. But the traditional ERP system serviced in enterprise mainly focused on optimization of internal process of business, it also made enterprises can not exchange information effectively with outside world, therefore, it is important to introduce e-commerce systems that service for communication. In the paper, based on the status study of the e-commerce implementation, it has studied the way e-commerce and ERP Integration and to the EB-ERP model presents a workable framework for model and case analysis. For the concrete implementation of the manufacturing enterprises it provides a theoretical basis and implementation of programs.

Heat flow and the origin of helium in natural gases from fault basins of the continental rift-valley in eastern China are discussed in terms of helium isotope geochemistry.3He/4He ratios in natural gases from the rift-valley range from 2.23 × 10−7 to 7.21 × 10−6, which are directly proportional to the concentration of helium and ΣNHC/ΣHC ratio in natural gases. Geological and isotope geochemical data suggest that helium in natural gases consists predominantly of crustal radio-genic and upper mantle-derived helium. In a simple mixing pattern between crustal He and mantle-derived He, mantle-derived helium in natural gases would account for 10–60%. Calculated values for heat flow (Q) range from 59.7 to 82.4mWm−2, of which about 60 percent in the rift-valley is derived from the upper mantle. Natural helium reservoirs would be found in the areas where the upper mantle uplifted greatly and heat flow is large in the continental rift-valley.