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Accelerated life tests (ALTs) are used to make timely assessments of the lifetime distribution of highly reliable materials and components. Life test under accelerated environmental conditions may be fully accelerated or partially accelerated. In fully accelerated life testing, all the test units are run at accelerated condition, while in partially accelerated life testing, they are both run at normal and accelerated conditions. The products can fail due to one of the several possible causes of failure which need not be independent. The purpose of this paper is to design constant-stress PALT with dependent competing causes of failure using the tampered failure rate model.

Gumbel–Hougaard copula is used to model and measure the dependence between the life times of competing causes of failure. The use of the copula simplifies the model specification and gives a general class of distributions with the same dependent structure and arbitrary marginal distributions.

The optimal plan consists in finding optimum allocation of test units in different chambers by minimizing the reciprocal of the determinant of Fisher Information Matrix. The confidence interval for the estimated values of the design parameters has been obtained and sensitivity analysis carried out. The results of sensitivity analysis show that the plan is robust to small deviations from the true values of baseline parameters.

The model formulated can help reliability engineers obtain reliability estimates quickly of high reliability products that are likely to last for several years.

The purpose of this paper is to consider the general k level step-stress accelerated life test with the Rayleigh lifetime distribution for units subjected to stress under progressive Type-I censoring.

The parameter of this distribution is assumed to be a log-linear function of the stress, and a tampered failure rate model holds. The progressive Type-I censoring reduces the cost of testing. Due to constrained resources in practice, the test design must be optimized carefully. A numerical study is conducted to illustrate the optimum test design based on several four optimality criteria under the constraint that the total experimental cost does not exceed a pre-specified budget.

This paper compares unconstrained and constrained optimal k level step-stress test. Based on the results of the simulation study, the cost constraint reduces cost and time of the test and it also, in the most cases, increases the efficiency of the test. Also, the T-optimal design is lowest cost and time for testing and it is found more optimal in both conditions.

In this paper, various optimization criteria for selecting the stress durations have been used, and these criteria are compared together. Also, because of affecting the stress durations on the experimental cost, the author optimize under the constraint that the total experimental cost does not exceed a pre-specified budget. The efficiency of the unconstrained test in comparison with constrained test is discussed.

Most of the literature on the design of accelerated life test (ALT) plan focus on a single system (subsystem) totally disregarding its internal configuration. Many a times it is not possible to identify the components that cause the system failure or that the cause can only be identified by a subset of its components resulting in a masked observation. The purpose of this paper is to deal with the planning of ramp-stress accelerated life testing for a high-reliability parallel system comprising two dependent components using masked failure data. Such a testing may prove to be useful in a twin-engine aircraft. A ramp-stress results when stress applied on the system increases linearly with time.

A parallel system with two dependent components is taken with dependency modeled by Gumbel-Hougaard copula. The stress-life relationship is modeled using inverse power law, and cumulative exposure model is assumed to model the effect of changing stress. The method of maximum likelihood is used for estimating design parameters. The optimal plan consists in finding optimal stress rate using D-optimality criterion.

The optimal plan consists in finding optimal stress rate using D-optimality criterion by minimizing the reciprocal of the determinant of Fisher information matrix. The proposed plan has been explained using a numerical example and carrying out a sensitivity analysis.

The model formulated can help reliability engineers obtain reliability estimates quickly of high-reliability products that are likely to last for several years.

Aim of the present monograph is the economic analysis of the role of MNEs regarding globalisation and digital economy and in parallel there is a reference and examination of some legal aspects concerning MNEs, cyberspace and e‐commerce as the means of expression of the digital economy. The whole effort of the author is focused on the examination of various aspects of MNEs and their impact upon globalisation and vice versa and how and if we are moving towards a global digital economy.

The equation of unified knowledge says that S = f (A,P) which means that the practical solution to a given problem is a function of the existing, empirical, actual realities and the future, potential, best possible conditions of general stable equilibrium which both pure and practical reason, exhaustive in the Kantian sense, show as being within the realm of potential realities beyond any doubt. The first classical revolution in economic thinking, included in factor “P” of the equation, conceived the economic and financial problems in terms of a model of ideal conditions of stable equilibrium but neglected the full consideration of the existing, actual conditions. That is the main reason why, in the end, it failed. The second modern revolution, included in factor “A” of the equation, conceived the economic and financial problems in terms of the existing, actual conditions, usually in disequilibrium or unstable equilibrium (in case of stagnation) and neglected the sense of right direction expressed in factor “P” or the realization of general, stable equilibrium. That is the main reason why the modern revolution failed in the past and is failing in front of our eyes in the present. The equation of unified knowledge, perceived as a sui generis synthesis between classical and modern thinking has been applied rigorously and systematically in writing the enclosed American‐British economic, monetary, financial and social stabilization plans. In the final analysis, a new economic philosophy, based on a synthesis between classical and modern thinking, called here the new economics of unified knowledge, is applied to solve the malaise of the twentieth century which resulted from a confusion between thinking in terms of stable equilibrium on the one hand and disequilibrium or unstable equilibrium on the other.

In the continuing endeavour to work towards ever better management, experience plays a crucial role. We learn from success, but we can learn much more from failure. Further, it is far better and cheaper when we learn from other people′s failures rather than our own. This monograph assesses the requirements of project management in relation to industrial projects, illustrating the factors that can result in failure by means of a series of case studies of completed and abandoned projects worldwide that have failed in one way or another. The key roles played by project planning and project cost control in meeting and overcoming the practical problems in the management of industrial projects are examined in detail. In conclusion the lessons that can be learned are evaluated and presented, so that we may listen and learn – if only we will.

Fault tolerant control surface actuation of unmanned aerial systems with take-off weights below 150 kg offers new design challenges due to limitations in mass, weight and cost. Conventional redundancy concepts need to be amended by smart operational strategies, enhanced sensor data provision and advanced failure mitigation. The paper aims for the design of a hardware-in-the-loop platform that enables the model-based development, verification, performance analysis and safety assessment of redundant and smart electromechanical actuators.

The hardware-in-the-loop platform was developed on the basis of various requirements and upcoming certification needs. One major aspect is the close relationship between model-based design approaches and the ability to keep hardware prototypes in the loop during the entire development process using virtual actuator control electronics.

The platform has proven to deliver valuable results during development of hardware and software prototypes. By its high flexibility and modularity, it has shown to be a versatile, attractive and cost-efficient alternative to conventional hardware-in-the-loop environments.

The presented simulation environment allows operating the components under realistic conditions by offering a control surface setup with redundant electromechanical actuators and a torque machine for hinge load simulation. It supports active–active, active–passive and single actuator operations to examine force-fighting phenomena, performance measurements and the exposure to actuator and control surface hardware faults.

The presented simulation environment provides precise knowledge about the behaviour of all involved components within all states of flight as well as mission and failure scenarios that are required during design, implementation and testing of fault tolerant actuation systems.

This paper aims to propose an innovative blockchain-based system enabling implementation of a bond-pays model in credit rating industry. Issuer-pays model has led to conflict of interest resulting in rating shopping and inflation. Alternative business models have their own problems, e.g. investor-pays model suffers from “free rider” and public dissemination challenges, whereas government-controlled business models can lead to market distortion. Bond-pays model has been difficult to implement owing to operational difficulties in managing co-ordination amongst multiple entities involved, often with conflicting goals. Blockchain technology enables inter-organizational systems that foster trust amongst non-trusting entities, facilitating business functions such as credit rating to be carried out.

This paper outlines current processes in credit rating business that has led to repeated rating failures and proposes a new set of processes, leveraging capabilities of blockchain technology to enable implementation of an arms-length bond-pays model.

A proof-of-concept system, namely, rating chain has been designed to implement a small part of the proposed model to establish technical feasibility in a blockchain environment.

A fully functional blockchain-based system on bond-pays business model, if built and adopted, could impact how credit rating market functions currently and could contribute to a reduction in rating-related challenges.

The proposal to adopt blockchain technologies in implementing a bond-pays model in credit rating industry is a novel contribution.

The study of international business has become increasingly important in recent years. So important that the American Assembly of the Collegiate Schools of Business (AACSB) has called for the internationalisation of business curricula. In 1992 and beyond, successful business people will treat the entire world as their domain. No one country can operate in an economic vacuum. Any economic measures taken by one country can affect the global economy. This book is designed to challenge the reader to develop a global perspective of international business. Globalisation is by no means a new concept, but there are many new factors that have contributed to its recently accelerated growth. Among them, the new technologies in communication and transport that have resulted in major expansions of international trade and investment. In the future, the world market will become predominant. There are bound to be big changes in the world economy. For instance the changes in Eastern Europe and the European Community during the 1990s. With a strong knowledge base in international business, future managers will be better prepared for the new world market. This book introduces its readers to the exciting and rewarding field of international management and international corporations. It is written in contemporary, easy‐to‐understand language, avoiding abstract terminology; and is organised into five sections, each of which includes a number of chapters that cover a subject involving activities that cross national boundaries.

The purpose of this paper is to highlight the key technical challenges that derive from the recently proposed European Artificial Intelligence Act and specifically, to investigate the applicability of the requirements that the AI Act mandates to high-risk AI systems from the perspective of AI security.

This paper presents the main points of the proposed AI Act, with emphasis on the compliance requirements of high-risk systems. It matches known AI security threats with the relevant technical requirements, it demonstrates the impact that these security threats can have to the AI Act technical requirements and evaluates the applicability of these requirements based on the effectiveness of the existing security protection measures. Finally, the paper highlights the necessity for an integrated framework for AI system evaluation.

The findings of the EU AI Act technical assessment highlight the gap between the proposed requirements and the available AI security countermeasures as well as the necessity for an AI security evaluation framework.

AI Act, high-risk AI systems, security threats, security countermeasures.