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Zero-failure reliability testing aims at demonstrating whether the product has achieved the desired reliability target with zero failure and high confidence level at a given time. Incorporating accelerated degradation testing in zero-failure reliability demonstration test (RDT) facilitates early failure in high reliability items developed within short period of time to be able to survive in fiercely competitive market. The paper aims to discuss these issues.

The triangular cyclic stress uses one test chamber thus saving experimental cost. The parameters in model are estimated using maximum likelihood methods. The optimum plan consists in finding out optimum number of cycles, optimum specimens, optimum stress change point(s) and optimum stress rates.

The optimum plan consists in finding out optimum number of cycles, optimum specimens, optimum stress change point(s) and optimum stress rates by minimizing asymptotic variance of estimate of quantile of the lifetime distribution at use condition subject to the constraint that total testing or experimental cost does not exceed a pre-specified budget. Confidence intervals of the design parameters have 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.

For some highly reliable products, even accelerated life testing yields little failure data of units in a feasible amount of time. In such cases accelerated degradation testing is carried out, wherein the failure termed as soft failure is defined in terms of performance characteristic of the product exceeding its critical (threshold) value.

Discusses the application of Wiener’s diffusion model as applied in engineering and physics. Shows how the model can be used in dealing with problems that arise in economic planning. Describes the scope of cybernetic thinking in the problems of planning in the Indian context. Gives details of the model’s application in this connection for the trends in growth levels of gross domestic product (GDP). Outlines its application to a problem of regional development.

The paper outlines a self-contained scheme for multiple networking agents at a location. It proposes a mathematical model for intelligent cloud entropy management systems. The purpose of this paper is to minimize the cost of system functionality by proposing the substantial use of a cloud-based system.

The paper proposes a hybrid cloud system, based on a fractional calculus of hybrid integral systems. Its discrete dynamics are suggested by using the fractional entropy type known as Tsallis entropy. This approach is based on the Wiener process (i.e. diffusion processes). This involves the net movement of information or data from a state of high meditation to a state of low observation. This property is a basic characteristic of hybrid cloud computing systems.

The paper offers a number of solutions to minimize the costs of cloud systems. The method is a proficient technique for presenting various types of fractional differential solutions.

Researchers are encouraged to test and modify the proposed method.

The paper includes suggestions for the expansion of a powerful method for managing and integrating cloud systems stably.

This paper addresses an acknowledged need to study how the cost function of cloud systems can be achieved.

Cybernetics is a branch of science which was originally based on the explanation of certain phenomena by reference to biology and medicine. Further development in cybernetics contributed greatly to the development of technical systems. It is proposed that now is the time for the methodological and technical approaches of cybernetics to be applied to biological and medical research, in conjunction with currently used technical and scientific methods. Some possible applications of the “ideology” of cybernetics to medicine are discussed. In particular, the development and treatment of cancer and psychofrenia are considered in terms of feedback. The role of feedback in social systems and states is also analysed.

EBT2 film, a convenient quality assurance (QA) tool with high 2D dosimetry resolution, has been widely used in the dosimetry application of radiation therapy with lots of benefits especially its self-development, water equivalent, energy independent and high spatial resolution. However, the higher inhomogeneity between the pixels of EBT2 image, needed to be averaged out according to the traditional method, but it could sacrifice the spatial resolution. To solve this problem, the purpose of this paper is to introduce a Wiener filter (WF) technique applied with a multi-channel (MC) method.

The EBT2 film was calibrated by using the percentage depth dose method combined with the WF technique and a MC method. Then the calculated film doses were compared with the measurement doses by the edge detector with the water phantom.

With high spatial resolution to be 0.2 mm, the results demonstrate that the EBT2 film calibration through both of the WF technique and MC method has higher accuracy (within 2 percent) and lower uncertainty.

A new technique of WF with MC method was presented to calibrate the dosimetry system of EBT2 film. With high spatial resolution (0.2 mm), the studies show that the combination of WF technique with MC method can have high accuracy with low noises to calibrate EBT2 film. This method can also be applied to all the QAs of treatment planning of radiation therapy by using the EBT2 film.

Degradation measurement of some products requires destructive inspection; that is, the degradation of each unit can be observed only once. For example, observation on the mechanical strength of interconnection bonds or on the dielectric strength of insulators requires destruction of the unit. Testing high-reliability items under normal operating conditions yields a small amount of degradation in a reasonable length of time. To overcome this problem, the items are tested at higher than normal stress level – an approach called an accelerated destructive degradation test (ADDT). The present paper deals with formulation of constant-stress ADDT (CSADDT) plan with the test specimens subject to stress induced by temperature and voltage.

The stress–life relationship between temperature and voltage is described using Zhurkov–Arrhenius model. The fractional factorial experiment has been used to determine optimal number of stress combinations. The product's degradation path follows Wiener process. The model parameters are estimated using method of maximum likelihood. The optimum plan consists in finding out optimum allocations at each inspection time corresponding to each stress combination by using variance optimality criterion.

The method developed has been explained using a numerical example wherein point estimates and confidence intervals for the model parameters have been obtained and likelihood ratio test has been used to test for the presence of interaction effect. It has been found that both the temperature and the interaction between temperature and voltage influence the quantile lifetime of the product. Sensitivity analysis is also carried out.

Most of the work in the literature on the design of ADDT plans focusses on only a single stress factor. An interaction exists among two or more stress factors if the effect of one factor on a response depends on the levels of other factors. In this paper, an optimal CSADDT plan is studied with one main effect and one interaction effect. The method developed can help engineers study the effect of elevated temperature and its interaction with another stress factor, say, voltage on quantile lifetime of a high-reliability unit likely to last for several years.

Existing studies of information systems development (ISD) control commonly examine controller-centric considerations, such as the antecedents and performance impacts of control mode choices. In contrast, little is known about the controllee-centric factors that may influence the effectiveness of control activities. Drawing on institutional theory, the purpose of this paper is to introduce the concept of control legitimacy to the ISD literature – a concept that past organizational research has linked to outcomes such as employee commitment and performance. Specifically, the authors explore how different dimensions of control activities (mode, degree, style) relate to controllee perceptions of control legitimacy in terms of justice, autonomy, group identification, and competence development.

Interviews were conducted with 20 practitioners across three companies. A structured data coding approach was employed and analysis was conducted within and across each case study.

The authors find that the control degree and control style can help explain control legitimacy perceptions better than control modes alone. For example, the results suggest that formal controls enacted in a bilateral style correspond with higher perceptions of justice and autonomy, when compared to formal controls enacted in a unilateral style.

The study results imply that ISD managers should be increasingly mindful of enacting controls in a way that is perceived to be legitimate by subordinates, thereby potentially enhancing both staff well-being and ISD performance.

This paper is written in memory of the late Stafford Beer. The paper engages with only one dimension of the whole man: Stafford Beer as the diagnostician and prognostician of the social conditions that he so keenly observed.

The paper revisits a talk that Stafford Beer gave, over three decades ago, to administrators of the UK National Health Service (NHS). It uses the content of the talk, entitled “Health and Quiet Breathing”, to diagnose the problems that have been encountered in the development of NHS information management strategies. The paper concludes with some brief personal recollections of Stafford Beer as a friend and as a teacher.

The paper finds Stafford Beer's managerial cybernetics to be a useful tool in understanding many of the problems that have beset NHS information management strategies: lack of operational research, problems in the commodification of information, financial scandal, and bureaucracy. In its examination of these issues, the paper recognises Stafford Beer's status as a legatee of not only Norbert Wiener but also of the great philosophers.

The paper demonstrates how the problem‐orientation of Stafford Beer's managerial cybernetics continues to be fresh and relevant to today's society and provides a brief portrait of him both as a friend and as a teacher.

The purpose of this chapter is to study the mathematisation of finance – excessive use of mathematical models in finance – which has been widely blamed for the recent financial and economic crisis. We argue that the problem might actually be the financialisation of mathematics, as evidenced by the gradual embedding of branches of mathematics into financial economics. The concept of embeddedness, originally proposed by Polanyi, is relevant to describe the sociological relationship between fields of knowledge. After exploring the relationship between mathematics, finance and economics since antiquity, we find that theoretical developments in the 1950s and 1970s lead directly to this embedding. The key implication of our findings is the realization that it has become necessary to disembed mathematics from finance and economics, and proposes a number of partial steps to facilitate this process. This chapter contributes to the debate on the mathematisation of finance by uniquely combining a historical approach, which chronicles the evolution of the relation between mathematics and finance, with a sociological approach from the perspective of Polyani’s concept of embedding.

This paper aims to investigate possibility of statistical detection of market completeness for continuous time diffusion stock market models.

The paper uses theory of forecasting to find criteria of predictability of market parameters such as volatilities and the appreciation rates.

It is known that the market completeness is not a robust property: small random deviations of the coefficients convert a complete market model into an incomplete one. The paper shows that market incompleteness is also non-robust: for any incomplete market from a wide class of models, there exists a complete market model with arbitrarily close paths of the stock prices and the market parameters.

The paper results lead to a counterintuitive conclusion that the incomplete markets are indistinguishable in the terms of the market statistics.