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This study aims to use an environomics method to assess the environmental impacts of selected gas turbine power plants in Nigeria.

In this study, exergoenvironomic analysis has been carried out to investigate the environmental impact of selected gas turbine power plants in Nigeria from an exergetic point of view.

The exergy analysis reveals that the combustion chamber is the most exergy destructive component compared to other cycle components. The exergy destruction of this component can be reduced by increasing gas turbine inlet temperature (GTIT). The results of the study show that thermodynamic inefficiency is responsible for the environmental impact associated with gas turbine components. The study further shows that CO₂ emissions and cost of environmental impact decrease with increasing GTIT.

The exergo-environomic parameters computed in this study are CO₂ emission in kg per MWh of electricity generated, depletion number, sustainability index, cost flow rate of environmental impacts (Ċ_env) in $/h and total cost rates of products (Ċ_Tot) in $/hr. For the period considered, the CO₂ emissions for the selected plants vary from 100.18 to 408.78 kgCO₂/MWhm, while cost flow rate of environmental impacts varies from $40.18 /h to $276.97 /h and the total cost rates of products vary from $2935.69/h to $12,232.84/h. The depletion number and sustainability index vary from 0.69 to 0.84 and 1.20 to 1.44, respectively.

In this study, exergoeconomic analysis and performance evaluation of selected gas turbine power plants in Nigeria were carried out. The study was conducted using operating data obtained from the power plants to determine the exergy efficiency, exergy destruction, unit cost of electricity and cost of exergy destruction of the major components of a gas turbine engine in the selected power plants. The results of exergy analysis confirmed that the combustion chamber is the most exergy destructive component compared to other cycle components as expected. The total efficiency defects and overall exergetic efficiency of the selected power plants vary from 38.64 to 69.33% and 15.66 to 30.72% respectively. The exergy analysis further shows that the exergy improvement potential of the selected plants varies from 54.04 MW to 159.88 MW. The component with the highest exergy improvement potential is the combustion chamber and its value varies from 30.21 MW to 88.86 MW. The results of exergoeconomic analysis show that the combustion chamber has the greatest cost of exergy destruction compared to other components. Increasing the gas turbine inlet temperature (GTIT), both the exergy destruction and the cost of exergy destruction of this component were found to decrease. The results of this study revealed that an increase in the GTIT of about 200 K can lead to a reduction of about 29% in the cost of exergy destruction. From exergy costing analysis, the unit cost of electricity produced in the selected power plants varies from cents 1.99 /kWh (N3.16 /kWh) to cents 5.65 /kWh (N8.98 /kWh).

This study presents thermodynamic analysis of the design and performance of eleven selected gas turbine power plants using the first and second laws of thermodynamics concepts. Energy and exergy analyses were conducted using operating data collected from the power plants to determine the energy loss and exergy destruction of each major component of the gas turbine plant. Energy analysis showed that the combustion chamber and the turbine are the components having the highest proportion of energy loss in the plants. Energy loss in combustion chamber and turbine varied from 33.31 to 39.95% and 30.83 to 35.24% respectively. The exergy analysis revealed that the combustion chamber is the most exergy destructive component compared to other cycle components. Exergy destruction in the combustion chamber varied from 86.05 to 94.67%. Combustion chamber has the highest exergy improvement potential which range from 30.21 to 88.86 MW. Also, its exergy efficiency is lower than that of other components studied, which is due to the high temperature difference between working fluid and burner temperature. Increasing gas turbine inlet temperature (GTIT), the exergy destruction of this component can be reduced.

This study mainly aims to explore the impact of management practices and managerial behavioral attributes on credit rating quality in Tehran Stock Exchange.

In this study, 214 firms were assessed from 2014 to 2020. The credit rating quality was measured through Technique for Order of Preference by Similarity to Ideal Solution and the entropy weighting method. In accordance with the theoretical literature, managerial entrenchment, managerial myopia, managerial overconfidence and managerial narcissism were considered as the managerial attributes. Furthermore, to examine management practices, cash flow management and accrual management were explored.

The results of this study showed that the cash flow from operations management and the accrual management has a significant positive effect on the credit rating quality. The managerial entrenchment, managerial narcissism and managerial myopia have significant negative effects on credit rating quality, while the effect of managerial overconfidence on credit rating quality is not significant.

Understanding the factors that affect the credit rating quality is of a great importance. Considering the significance of cash management in the present era and the impact of managerial psychological and behavioral characteristics in the development of the organization, empirical results of this study can help investors, capital market regulators and other stakeholders to strengthen the firm and better decisions.

This paper aims to investigate the organisational changes (OCs) and the development of Chinese reformed township and village enterprises (RTVEs), their marketing and R&D strategies, and the impact of changes in terms of overall performance.

A case study methodology involving semi‐structured interviews is adopted. The unit chosen is the Guotai International Group (GTIG) in Zhangjiagang, Suzhou, Jiangsu province, China, in which the organisational changes over a period of over 40 years are analysed.

OCs in Chinese RTVEs are found to be driven by a combination of local government plans and market forces. Considering the hybrid nature of the organisation and ownership structures, changes in Chinese RTVEs follow a very much “top‐down” approach.

The findings imply that managers appointed by the state in RTVEs usually lack the necessary skills in marketing and business management, and can be resistant to organisational changes, such as the willingness to undertake risks. As a result, RTVEs may become stuck in a cycle of low‐cost, low‐tech products, inhibiting any breakthrough in developing their own quality brands.

This is one of few papers studying change over a long span of time to arrive at research findings that will be useful to academic researchers in their future work. The qualitative findings from this paper would also enrich the literatures on organisational change in Chinese RTVEs.

Netiquette is derived by merging the words network and etiquette. More specifically the term netiquette has been described as the conventions of politeness recognized on Usenet and in mailing lists. In the context of the new Internet global culture, attempts are being made to identify common standards of etiquette. Literally hundreds of specific netiquette suggestions are published. Identifies the following most frequently cited specific suggestions for online users: think first; write in upper and lower case; avoid abbreviations; be concise; avoid smileys; don’t flame; don’t take offense easily; don’t evangelize; and know the audience. Netiquette breaches do not always bring retribution. Most breaches of politeness and courtesy may do no more than reflect poorly on the individual user. One who knows the rules of this new culture may well have an advantage over one who does not.