This paper studies the patent race problem of communication enterprises investing in communication technologies, and constructs a portfolio optimization model which considers the expected returns, investment risks, and replacement costs, in order to achieve the dual goals of maximizing the net investment income of backward enterprises and minimizing the expected investment risk. Through numerical experimental analysis, the optimal investment portfolio strategy under different risk levels and the impact of different risk levels on the net income of lagging company are obtained. The research results show that due to the backward research in the first stage of the backward enterprises, when their own investment decision-making power is relatively high, they can focus on the development of self-interested key technology areas in order to achieve the victory of the patent race.

The research is focused on the evolution of the enterprises, in the field of specialized professional services, medium-period, enterprises that implemented projects financed within Regional Operational Program (ROP) during the 2007–2013 financial programming period. The analysis of the economic performance of the micro-enterprises corresponds to general objectives, but there can be outlined connections between these performances and other economic indicators that were not considered or followed through the financing program. The study case is focused on the development of micro-enterprises in the services area, in the Central Region, Romania (one of the eight development regions in Romania). The scientific approach for this article was based on a regressive statistical analysis. The analysis included the economic parameters for the enterprises selected, comparing the economic efficiency of these enterprises, during implementation with the economic efficiency after the implementation of the projects, during medium periods, including the sustainability period. The purpose of the research was to analyse the economic efficiency of the selected micro-enterprises, after finalizing the projects’ implementation. The authors intend to point out the need for a managerial instrument based on the economic efficiency of companies that are benefiting from non-reimbursable funds. This instrument should be taken into consideration in planning regional development at the national level, regarding the conditions and results expected. Although the authors used regressive statistical analysis the purpose was to prove that there is a need for additional managerial instruments when the financial allocations are being designed at the regional level. This study follows the interest of the authors in proving that the efficiency of non-reimbursable funds should be analysed distinctively on the activity sectors.

Sustainable development within music education is essential, particularly in ensuring that popular music can continually and effectively serve educational systems. This research aims to 1) examine pop music chord progression, 2) develop a chord progression book specifically for teaching music students, and 3) evaluate the effectiveness of this educational tool in improving music composition skills. A mixed-methods approach, incorporating both qualitative and quantitative research, was used. Research tools included an interview guide, Ioc forms, a textbook, and a performance assessment form. Interviews were conducted with five experts in pop music composition, while a group of 14 undergraduate music students participated in the experimental study. These methods evaluated how teaching popular music chord composition enhances students’ practical composition abilities. The findings indicate that 1) chord composition in popular music primarily involves five aspects: melody, rhythm, chord structure, music form, and melody development techniques, with melody and chord as the foundational elements; 2) the chord progression textbook for popular music differs from traditional composition theory texts, combining theory and practical application with a focus on chord progression techniques; and 3) instruction in popular music chord composition significantly enhances students’ skills in melody creation, production, and listening, ultimately fostering practical music creation abilities. This study supports the sustainable integration of popular music in both music infrastructure construction and music education system development, offering insights into how such integration can drive long-term advancements in music education.

Our intention in assembling this special issue of the Journal of Infrastructure, Policy and Development is to offer a state-of-the-art tour through the political economy issues associated with the provision of public infrastructure, and with the use of Public-Private Partnerships (PPPs) in particular. Anyone who is familiar with PPPs cannot fail to be impressed by the diversity of positions and claims regarding their properties. Some scholars maintain that PPPs are an efficient tool to enhance productivity due to their ability to manage demand-side risk. In contrast, other scholars see in PPPs a scheme whereby the public assumes the risk while the private partner takes the profit.

This study explores the influence of human resource empowerment on the establishment of green human resource management (GHRM) within Tehran's 14th district municipality. Utilizing a descriptive-analytical research approach, the study targets the practical implications of empowerment strategies on GHRM implementation. The research population consists of 1500 employees from the 14th district, based on the 2017 census. A sample of 306 respondents was selected using Morgan's table. Data were collected via a structured questionnaire developed from the study's conceptual framework and research hypotheses. The questionnaire's validity and reliability were confirmed through expert review and Cronbach's alpha (0.9). Descriptive statistics outline the background and primary variables, while inferential statistics, particularly the Pearson correlation test, were used to evaluate the hypotheses. Results indicate that human resource empowerment positively affects the establishment of GHRM in Tehran's 14th district municipality.