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The purpose of this study is to perform an off-design analysis of the inverted Brayton cycle engine.

The off-design analysis equations of the inverted Brayton cycle engine were first derived in this study and the control parameters of the inverted Brayton cycle engine were first determined and investigated.

It is observed that by controlling the total temperature decrease in cooling section, it is possible to adapt the engine for low specific fuel consumption working conditions or high thrust working conditions. Specific fuel consumption is reduced by 27.1 % by stopping cooling in the cooling section and thrust is increased by 27.6 % by working with full load of the cooling section (500 K temperature decrease in cooling section). It is observed that thrust depending on the flight Mach number increases with an increase in flight Mach number and reaches a peak value at 5.21 flight Mach number and reduces by 80.8 % at 6 flight Mach number relative to the peak value. The specific fuel consumption increases rapidly as the Mach number increases, and the specific fuel consumption is 49.0 g/[kN.s] at Mach 1, reaches 70.4 g/[kN.s] at Mach 5 and increases to 412 g/[kN.s] at Mach 6. The specific fuel consumption increases from 68.1 to 73.0 g/(kN.s) and the thrust decreases from 16.5 to 13.3 kN as the total preburner exit temperature increases from 1,500 to 2,000 K. Specific fuel consumption decreases from 83.1 to 64.8 g/(kN.s) and thrust increases from 4.60 to 11.08 kN depending on afterburner exit total temperature increase from 1,800 to 2,500 K.

The cooling section reduces total temperature of the gas flow to lower values to increase the compressor total pressure ratio. The compressor increases the total pressure of the gas flow to the optimum total pressure ratios to increase the nozzle exit Mach number and gain more thrust. The afterburner increases the total temperature of the gas flow to increase the sound speed in the nozzle exit to increase thrust. The nozzle expands the gas flow to reduce the static pressure of the gas flow to near the optimum value, atmosphere pressure, to increase thrust and reduce specific fuel consumption.

Hypersonic and supersonic air vehicles can use the current engine model for the its own propulsion systems.

After first heavier than air flight, aero engines was designed for only used for aero vehicle. Internal combustion engines were used for propelled propeller aircraft at the first term of aircraft. However, propeller-propelled aircrafts are not sufficient to increase aircraft velocity to supersonic Mach numbers due to the shock losses of propeller, so the supersonic era was only introduced by revolution in propulsion systems with new concept. A jet engine was developed to be candidate for supersonic flight.

Off-design analysis equations of an inverted Brayton cycle engine were first derived in this study. Furthermore, the control parameters of the inverted Brayton cycle engine were first determined and investigated in this paper.

Purpose: COVID-19 pandemic is among the most important events of the 21st Century. Its global character and the multi-dimensional fallouts it has on communities worldwide further increase the importance of the pandemic. During the period of more than one year since the declaration of the pandemic, the communities failed to provide a lasting solution other than the face masks, social distance, and hygiene. Failure to fight the pandemic with considerable success subsequently raised the topic of revising the policymakers’ previous predictions at the start of the pandemic based on incomplete information. So, the calendar put forward for the pandemic went forward day by day, and the authorities who failed to adopt a prudent approach were obliged to pay increasingly higher costs for their mistakes. In the chapter, the financial and economic effects of the pandemic in selected countries are examined. While examining the policies followed in these countries, in terms of fiscal stimulus packages and monetary expansion packages, it is aimed to shed light on the pandemic experience in the Turkish economy and to develop policy recommendations. Thus the persistence of the pandemic pushes all countries to update their current policies and seek new methods. This chapter aims to examine developed and emerging economies in the covid-19 era that have implemented policies to struggle with the pandemic and whose policy framework can be accessed.

Methodology: To do this we carried out a literature review of the Economic and Fiscal Effects of COVID-19 Pandemic during 2020 and early 2021.

Findings: Countries like the United States, United Kingdom, and Germany are believed to have taken strong measures to minimize the damages on the economy due to the pandemic, while other countries like Russia, India, and Brazil are deemed to have mounded new policies within the framework of their internal dynamics. One should also note that, in addition to the individual efforts of each European country, the European Union has also played a decisive role in the policies of its member states for crisis management institutionally.

Purpose: The study is designed to investigate internal audit functions in banks’ cyber security governance processes by assessing the pros and cons of blockchain technology through swot analysis.

Need of the Study: The study is needed to clarify the complexities in internal audit fields integrated into cyber security governance and explore the blockchain application opportunities.

Methodology: Blockchain technology is explored from the point of technical concepts and policy framework by swot analysis to propose a set of solutions for continuous audit methods in cyber security governance.

Limitations: The sample of this study is limited to the personal ideas and evaluations of academicians, experts in the banking sector and legal regulators of Türkiye, with the data received between March and December 2021.

Findings: Blockchain technology can be applied as an alternative to conventional risk control methods as a mechanism of continuous audit methods to reduce human mistakes and special causes.

Practical Implications: The control of risk management operations for cyber security processes should be performed with the support of audit units of the banks. Therefore, innovations are being implemented to cyber-risk controls to drop the defects that cause technical and ethical issues with blockchain technology as a way of using automation. So, this advancement can be applied in audit operations practically for unanticipated events which can emerge in cyberspace to mitigate inherent risk to residual levels. However, there is ample room to adapt this technology for cyber security management and audit practices from the point of view of the labour force, regulations and environmental issues.

Information security has become an essential entity for organizations across the globe to eliminate the possible risks in their organizations by conducting information security risk assessment (ISRA). However, the existence of numerous different types of risk assessment methods, standards, guidelines and specifications readily available causes the organizations to face the daunting tasks in determining the most suitable method that would augur well in meeting their needs. Therefore, to overcome this tedious process, this paper suggests collective information structure model for ISRA.

The proposed ISRA model was developed by deploying a questionnaire using close-ended questions administrated to a group of information security practitioners in Malaysia (N = 80). The purpose of the survey was to strengthen and add more relevant additional features to the existing framework, as it was developed based on secondary data.

Previous comparative and analyzed studies reveals that all the six types of ISRA methodologies have features of the same kind of information with a slight difference in form. Therefore, questionnaires were designed to insert additional features to the research framework. All the additional features chosen were based on high frequency of more than half percentage agreed responses from respondents. The analyses results inspire in generating a collective information structure model which more practical in the real environment of the workplace.

Generally, organizations need to make comparisons between methodologies and decide on the best due to the inexistence of agreed reference benchmark in ISRA methodologies. This tedious process leads to unwarranted time, money and energy consumption.

The collective information structure model for ISRA aims to assist organizations in getting a general view of ISRA flow and gathering information on the requirements to be met before risk assessment can be conducted successfully. This model can be conveniently used by organizations to complete all the required planning as well as to select the suitable methods to complete the ISRA.

The purpose of this paper is to investigate the joint influence of two factors (companies’ performance and growth) on the company’s capital structure and to determine the conditions for financially sustainable competitive strategies in the coordinates profitability and growth.

The study sample includes 1,996 companies from 6 high-tech industries in Russia (panel data: 7,984 observations). The authors use regression models with random effects and carry out a three-dimensional visualization of the resulting dependencies.

The study found that profitability improves the capital structure (reduces the share of borrowed capital) and, on the contrary, the growth of companies (assets growth or sales growth) increases the leverage ratio. In the case of assets growth, the combined influence of two factors reduces the negative effect of assets growth. The results have shown that the outstripping growth of most high-tech companies requires an increase in debt capital and deterioration in the capital structure and financial stability.

In general, based on the results of this study, the authors have identified groups of fast-growing companies that need financial support, and have defined the main areas of impact (reducing the loan burden and increasing profitability) that will allow these companies to maintain high growth rates and demonstrate advanced development.

The relationships (which the authors identified between the control variables, the studied variables and leverage) were obtained for the first time for a sample of companies in high-tech industries and services in bigger transition country (Russia).

The development of technologies for the conduct of cyber operations represents an opportunity for states to defend their interests in international relations but also bears risks and challenges. Since the early 2000s, the United Nations “group of governmental experts (GGE) on developments in the field of information and telecommunications in the context of international security” debates on this issue. This paper aims to investigate how states are challenged in the development of international cyber norms and where capacity to act is idle, i.e. to assess how much has been reached in the international community’s debate on cyber threats and malicious behaviors in the international security context and to identify directions to move GGE work further.

The methodology uses an extensive text-based desk research and relies on a thorough collection, analysis and interpretation of the United Nations (UNs) documents. When specific substantial topics are addressed in the GGE, the content of the debate was confronted with issue-specific academic literature on those matters.

The results highlight that the GGE managed to gather consensus on a number of cooperation and normative measures in this politically highly sensitive topic and more deliverables are expected during this and next year. The paper identifies a weakness in terms of operational implementation though. The paper proposes a few examples of concrete headways that could complement existing consensus, especially on the implementation side.

Because of its political sensitivity, the GGE has worked with discretion and has attracted little academic attention. This paper is an original and timely attempt to assess the achievements and possible outlook of this endeavor of the international community, including the incipient work of a recently established open-ended working group. It also attempts to connect the subject matter discussed in the UN with related academic literature, including in respect of definitional and conceptual issues.