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This paper aims to enhance the reliability of self-validating multifunctional sensors.

An effective fault detection, isolation and data recovery (FDIR) strategy by using kernel principal component analysis (KPCA) coupled with gray bootstrap and fault reconstruction methods.

The proposed FDIR strategy is able to the address fault detection, isolation and data recovery problem of self-validating multifunctional sensors efficiently.

A KPCA-based model which can overcome the limitation of existing linear-based models is used to achieve the fault detection task. By using gray bootstrap method, the position of all faulty sensitive units can be calculated even under the multiple faults situation. A reconstruction-based contribution method is adopted to evaluate the amplitudes of the fault signals, and the fault-free output of the faulty sensitive units can be used to replace the fault output.

The purpose of this paper is to investigate the performance of a turbine structure of the oil and gas Egyptian company in terms of reliability, mean time to failure (MTTF), mean time to repair (MTTR) and mean time between failures (MTBF) under fuzzy environment and working criteria. This paper examines the impact of the failure of various components on the complete turbine structure of the oil and gas system.

To overcome the problem of uncertain behavior of available data for various components, the right triangular generalized fuzzy number (RTrGFN) is proposed to be taken into the account to express the uncertainty which attains some tolerance in data. Furthermore, reliability indices are calculated with the help of the Lambda Tau method and the arithmetic operations on right generalized triangular fuzzy numbers (RTrGFN).

This paper explores the reliability of a repairable 3 out of 4 structure of turbines and along with the other parameters namely MTTF, MTTR and MTBF; under a fuzzy environment. Failure rates and repair times are expected to be exponential. The ranking of components of the structure is being found to decide the priority for maintenance.

This paper investigates the performance of the system with different spread/tolerance like 15%, 25% and 50% of crisp data. It helps to predict realistic results in the range value. To enhance the system's performance, the most important item of the system requires greater attention. For this, the authors find the sensitive part by ranking. For ranking, an extended approach has been developed to find the sensitive unit of the system by using the right triangular generalized fuzzy number. This paper explores the most and least sensitive component of the system, which helps the maintenance department to plan the maintenance action.

The purpose of this paper through the redundant monitoring unit reflecting the real-time temperature change of the array, an adaptive refresh circuit based on temperature is designed.

This paper proposed a circuit design for temperature-adaptive refresh with a fixed refresh frequency of traditional memory, high refresh power consumption at low temperature and low refresh frequency at high temperature.

Adding a metal oxide semiconductor (MOS) redundancy monitoring unit consistent with the storage unit to the storage bank can monitor the temperature change of the storage bank in real time, so that temperature-based memory adaptive refresh can be implemented.

According to the characteristics that the data holding time of dynamic random access memory storage unit decreases with the increase of temperature, a MOS redundant monitoring unit which is consistent with the storage unit is added to the storage array with the 2T storage unit as the core.

The purpose of this paper is to investigate the manufacturer’s production, pricing and green technology investment decision problem when strategic customer behavior and carbon emissions-sensitive random demand is taken into consideration and discuss the impact of carbon emissions-sensitive demand on the manufacturer’s operation strategies, total carbon emissions and maximum expected profit.

The authors formulate a model to introduce carbon emissions-sensitive demand into the newsvendor framework with strategic customer behavior. The authors characterize the rational expectations equilibrium to derive the optimal solutions to the manufacturer. The authors analyze the effects of carbon emissions-sensitive demand on the manufacturer’s optimal strategies, total carbon emissions and maximum expected profit by comparative analysis.

The authors obtain the manufacturer’s optimal production, pricing and green technology investment strategies under rational expectations equilibrium in scenario of price-sensitive demand and that of carbon emissions-sensitive demand, respectively. The authors find that as customer demand changes from price-sensitive demand to carbon emissions-sensitive demand, the manufacturer’s optimal prices are the same but optimal production quantity, optimal unit carbon emissions and maximum expected profit go down. Though the total emissions decrease, the carbon emissions reduction would not increase as the demand is more carbon emissions-sensitive. Whether it increases or decreases depends on the model parameters.

Carbon emissions-sensitive demand and strategic customer behavior are considered simultaneously in an integrated model. The result can guide the manufacturer decision-making. The proposed model are hoped to shed light to the future works in the field of sustainable supply chain management.

With the pressing need for environmental conservation, regulatory authorities are actively looking for measures to prevent global warming. In the proposed inventory model for deteriorating items, demand is dependent on the selling price and green technology investment (or carbon reduction investment) for the green product (GP), as well as an investment in price-based preservation technology to slow down the pace of deterioration. Furthermore, emission reduction measures are put in place to reduce carbon emissions (CEs).

The current study executed a thorough literature review to determine how to improve supply chain management performance. Furthermore, assumptions are made to fill research gaps, and a mathematical model is created to address the problem mentioned above. To collect the data, the available inventory literature was reviewed. Additionally, numerical illustrations and sensitivity analyses are presented to emphasize the model's robustness.

The research indicates that it is more prudent to invest in preservation technology based on its selling price in order to control the rate of deterioration. In addition, the proposed model facilitates the management of deteriorated waste through salvage trading and emission reduction investment. The findings validate sustainable practices with a 20.86% increase in profit and a 21.4% decrease in CEs, thereby signifying environmental and economic benefits.

The proposed model enhances understanding of the impact of investments in price-based preservation technology and carbon reduction efforts on consumer perceptions of their intention to purchase GPs. Moreover, the study provides valuable insights by identifying important recommendations for policymakers regarding areas that require further investigation. This guideline can help identify both current and unexplored gaps, enabling researchers to direct future research efforts toward producing new products.

Ensuring safe operation of a urea fertilizer plant (UFP) is a vital aspect for its functioning and production. Clearly the safe operation of such systems can only be archived with proper and effective maintenance scheduling and through controlling its failures as well as repairs of the components. Also for this, the concern plant management must have the information regarding the failures that affects the system's performance most/least. The objective of this study is to analyze mathematically the factors that are responsible for the failure/degradation of the decomposition unit of UFP.

The considered system has been modeled by the aid of Markov's birth–death process with two types of failures for its components: variable (which are very similar in practical situations) and constant. The mathematical model is solved by the help of Laplace transform and supplementary variable technique.

In the present paper, the availability, reliability and mean time to failure (MTTF) are computed for the decomposition unit of the UFP. The critical components that affect the reliability and MTTF of the decomposition unit are identified through sensitivity analysis.

In this paper, a mathematical model based on the working of the decomposition unit of a UFP has been developed by considering two types of failure, namely, variable failures rates and constant failure rates (which has not been done in the literature for the decomposition unit). Conclusions in this paper are good references for the improvement of the same.

The purpose of this paper is to enhance sustainability in affordable housing in Saudi Arabia within an effective locally adopted sustainability assessment tool by discussing the multi interdisciplinary concept of sustainability in the built environment and introducing environmental indicators which are recently developed to foster environmentally responsible practices. The study aim expands beyond proposing sustainable feasible alternatives for existing affordable housing project in Saudi Arabia, namely, Al-Ghala project, to appropriating the measuring tool itself to make the review process easier, faster and more effective.

Al-Ghala project, a typical affordable housing project is selected to act as a case study for this research. The housing units are assessed according to LEED to obtain the overall evaluation which obviously reflects the quality of the project sustainability. Elements that negatively affect the score and suggested feasible remedies are then identified, as well as inapplicable and inappropriate LEED components. The data were complemented by observation, interviews with occupants and project management team, monthly consumption rates of water and electricity, in addition to computer modelling and analysis by Ecotect and Green Building Studio.

Sustainability in affordable housing requires a holistic framework that promotes environmentally responsible practices including design, construction and management phases. LEED provides evidence that it can considerably contribute in enhancing sustainability of post-occupied affordable housing units by identifying points of weakness that lead to inefficient use of energy, water and materials; paving the way for a wide range of sustainable modifications. In addition, for LEED to be competent in Saudi Arabia a native version needs to be developed in which local circumstances are taken into consideration.

According to the wide range of subjects covered by LEED, some elements could not be measured in depth. Impact of modifications proposed for LEED needs to be tested further.

The paper includes implications for the development of feasible environmentally sensitive affordable housing in Saudi Arabia.

This paper fulfills an identified need to study how affordable housing can be made sustainable.

THE Farnborough 1966 Show was at first glance much the same mixture as before, but the second glance was the more revealing. The participation in the flying display of European aircraft by no means swamped the air, even if the Italian verve took the acrobatic honours, but the theme of collaboration with other countries was to be found on practically every stand inside the exhibition tent. It was obvious that the smaller firms not directly involved in production agreements with other nations were very export conscious. The pacemaker of all this collaboration was of course the Concorde, only to be seen in model form, but rapidly taking shape at Toulouse and Filton, and many of the equipment manufacturers had Concorde hardware on display. Beagle announced the Pup, Britten‐Norman produced the production Islander, and Handley Page showed the Jetstream mock‐up. After many years of neglect, the industry is now taking an interest in the general aviation market. The P.1127 (R.A.F.) made its first appearance. The paradox of the P.1127 is that it is almost a part of Farnborough history, yet there is no other V/S.T.O.L. aircraft in the world that has but a fraction of the operating experience it has gained. Farnborough this year gave the impression of being more a serious trade show, and less a public spectacle. Sir Richard Smeeton, Director of the Society of British Aerospace Companies, reported that the exhibiting firms had received more serious business enquiries this year than ever before, and he forecast that 1968 would be a vintage year, which would see the appearance of the HS.801, the Concorde and Jaguar in the Farnborough skies. It is not possible to cover every exhibit shown at the Farnborough Show, but the following report describes a wide cross‐section beginning with the exhibits of the major airframe and engine companies.

THE period of 40 years since man first flew with the aid of an internal combustion engine has seen many changes in aircraft power units. Power has increased to an astonishing extent, yet reliability has also been obtained. Unfortunately, however, the amount of skill and knowledge required to obtain the best results from an engine can hardly be said to have decreased.