In this paper, the focus is on mechanical systems that, like a ship or a submarine, perform risky missions and that must remain operating for the whole mission time. Missions take place far from the operational base and so, in case of failures, although repairs are possible, spares parts cannot be resupplied. Hence, given space constraints, the problem is to define the optimal set of spare parts that should be taken aboard, to maximize the probability to complete the mission. To solve this problem, we propose a constructive algorithm that generates the Pareto Optimal Frontier of all the non-dominated solutions, in terms of the system’s reliability and of required space. At first, the algorithm is formulated in a generic way; next, it is contextualized to the common case of Weibull distributed failure times. In this condition, the underlying equations of the model cannot be solved in closed form and an approximated procedure is proposed and validated through extensive numerical simulation.

This study examined the causal relationships between inflation, Gross Domestic Product (GDP), domestic savings, and investment in Zimbabwe using Toda-Yamamoto causality tests and the Autoregressive Distributed Lag (ARDL) approach with secondary data spanning from 1990-2022. The Granger causality analysis revealed a bidirectional causal effect between inflation and GDP, indicating that inflation significantly impacts the country's economic growth. Additionally, the analysis showed a unidirectional causal relationship from inflation to domestic savings, suggesting that high and persistent inflation can erode the value of existing savings and discourage individuals from saving. Furthermore, the study found a distinct causal flow from savings to investment, without feedback in the opposite direction, highlighting the crucial role of a robust savings culture in providing the necessary foundation for sustained investment and economic growth. The ARDL approach provided further insights into the dynamic relationships between these variables. In the short run, lagged GDP and current and lagged savings positively influenced GDP, while the second lag of savings had a negative impact, supporting the Carroll-Weil hypothesis that savings typically follow, rather than precede, economic growth in the short run. The analysis also found a positive short-run and long-run relationship between investment and GDP, supporting the view that investment is an important factor of economic growth. The study recommends that the policy makers can leverage the synergies between savings, investment, and inflation management to foster sustained economic growth and development in line with the government development policies. Developing policies to attract savings and reduce the cost of savings, as well as promoting long-term savings over transactional savings, can increase the country's overall savings base.

The main objective was to examine the impact of social norms, habits, and perceived behavioral control towards intention and its impact on energy-saving behavior. Also, the direct effects of habits and perceived behavioral control were examined towards energy-saving behavior. The target population was based on citizens of Saudi Arabia while the data collection was conducted using a quantitative approach. The purposive sampling was used, and data was analyzed using PLS-SEM using SmartPLS 3.2.8. The results show that habits had insignificant impact on energy-saving behavior. The habits had a significant impact on intention. The intention had an impact on energy-saving behavior. The perceived behavioral control had an impact on intention. The social norms had an impact on intention. We recommend that people should enhance their perceived behavioral control by believing on their attitude and feelings towards developing positive intentions that further leads towards energy saving behavior.

The decision to purchase the best available electric power wheelchair (EPWC) for a person with a disability in a low-resource context is very stressful, whether it is based on financial circumstances or the availability of medical solutions. The study's objective is to assess the EPWC options available on the market, focused on a set of conflicting criteria. In this research, three multi-criteria decision-making (MCDM) approaches are used to make decisions. ENTROPY method for weightage calculation of various parameters, COPRAS and EDAS methods for evaluating and ranking alternatives are applied. Both COPRAS and EDAS are applied separately for ranking of selected wheelchair models, and to check the robustness of the applied method, sensitivity analysis on cost criterion is carried out. The result shows that for both methods, EPWC-1 is the top priority model to buy, whereas EPWC-7 is the worst model for COPRAS, and EPWC-10 is the worst model for EDAS among the ten alternatives.

The field of strategic innovation (SI) has been garnering increasing research interest, with studies adopting and employing varying definitions and creating different methods for its measurement. Despite the innumerable studies, few have addressed manufacturing and small and medium-sized enterprises (SMEs), particularly those focused on Middle East countries, in light of the relationship between structural capital (SC) and SI. Hence, the present work is primarily aimed at examining the role of SC in SI and the performance of manufacturing SMEs. It employed the survey method to gather data from the study sample of 284 Yemeni manufacturing SMEs and the hypotheses were tested using Partial Least Squares-Structural Equation Modelling (PLS-SEM). On the basis of the results, there is a significant influence of SI on performance; SC also has a moderating role of on this relationship. The present study is expected to contribute to the creation of a measurement system for SI in SMEs, stressing each component of SI in enhancing the performance of such enterprises.

This article studies the mechanical characterization of impact loads on polyamide fibers. Using synthetic ropes in mooring systems, these are subject to static loads, but dynamic loads are also expected. One of the dynamic loads that can occur on cables are sudden loads, which makes the analysis of impact loads important. In this study, impact cycles were applied to polyamide multifilaments until rupture with different impact masses, and considering the conditions: dry, after 6 hours of immersion in water and after 24 hours of immersion in water. The analysis of the immersed conditions allows us to interpret the plasticizing effect that moisture exerts in polyamide, through loss stiffness in the rupture test. The results show that the increase in immersion time represents decrease in the breaking strength, and also in the resistance to impact cycles. A curve parameterization is proposed that relates the number of impact cycles and the percentage of Yarn Break Load used in the impact, getting through the coefficient of determination the best model. For force versus time graphs, obtained in each impact cycle, the energy dissipation in the multifilament can be observed in two main mechanisms: the first is the elastic deformation in form of ricochets, the second is the plastic deformation by stretching/elongation. The force-time graphs of impact cycles and the number of impact cycles to failure are measures that show performance for impact dynamic loads. Attention should be the plasticizing effect caused by water, as it reduces the static and dynamic mechanical strength of polyamide.

In examining for unique insecticidal agents, two derivatives namely, 2-((3-cyano-4,6-distyrylpyridin-2-yl)thio)-N-(4-nitrophenyl)acetamide (2) and 3-amino-N-(4-nitrophenyl)-4,6-distyrylthieno[2,3-b]pyridine-2-carboxamide (3) were synthesized from distyrylpyridine-2-thione (1). The new compounds were structurally clarified by spectral and elemental analysis data. The insecticidal activity of these compounds were carried out against cowpea aphid, Aphis craccivora Koch. It is demonstrated that the compounds 2 and 3 have noteworthy insecticidal activity against nymphs of cowpea aphid with LC50 values of 0.025-0.027 ppm and 0.005-0.006 ppm after 24 h and 48 h of treatment, respectively. Also, the compounds 2 and 3 have noteworthy insecticidal activity against adults of cowpea aphid with LC50 values of 0.112-0.129 ppm and 0.014-0.015 ppm after 24 h and 48 h of treatment, respectively, that were comparable to that of the control acetamiprid.

Oxygen-containing heterocycles are largely distributed in natural and synthetic compounds. Coumarins are among the most famous heterocycles which possess one oxygen atom in their rings. Coumarins are classified as multifunctional scaffold and are used as anti-oxidant reagents, anti-inflammatory, anti-microbial, anti-fungal, anti-HIV active, analgesic, anti-histaminic, insecticides, dyes, herbicides, sensitizers, perfumes, cosmetics and food additives. Due to their diverse applications in industrial and pharmaceutical fields, many chemists have given significant interest to these compounds. Herein, the review highlights various methods for the synthesis and interactions of coumarin moiety as one of the most efficient categories of heterocycles.

This research tries to find a relationship between audit quality and audit software, impacted by the latter. In this study, multiple sentiments of audit professionals and finance executives on the relation of audit software and quality of audit in Kuwait are examined where, on the basis of agreed perspectives of professionals, it was found that audit software positively influences audit quality. This particular article tries to extend the previous works and emphasizes on the observation of audit professionals and their perspectives through a well-structured survey and semi-structured interviews. This study is to identify the distinctiveness of the audit industry in Kuwait comparing market size and available inadequate local auditors. The authors try to establish the relationship between audit quality and audit software considering the fact that acceptance of audits software will definitely give a more effective and robust audit process to cover market needs. The paper also considers the auditors’ training and experience as a moderating factor for the adoption and usage of audit software in auditing practices in Kuwait, resulting in useful insights on the effects of the adoption and use of auditing software in enhancing the quality of audit reports as well as suggesting resources for the use of technological developments in auditing practices. Thus, the study contributes to the extant literature on the dynamics for the adoption and usage of computerized systems in auditing practices to improve the quality of audit reports.

Halal food is food whose halal status is regulated by sharia institutions such as LPPOM MUI which is set by the government. The halal status of food must be traced from the process of raw materials, processing, packaging, transportation, and distribution to the final consumer. It is difficult to trace the certainty of halal food, especially beef in Medan City because the supply chain information from upstream to downstream is not transparent. To increase the transparency of beef status and increase consumer confidence, especially Muslim consumers, a distributed and transparent system is needed, where many parties can access the status of food at any time. So Blockchain technology is used to help track the halal status of beef along the supply chain. The purpose of this study is to design a system to obtain information certainty that beef distributed along the supply chain is halal and safe for consumption by utilizing Blockchain technology and to increase public safety and trust in the LPPOM MUI halal certification system. Based on the discussion and research analysis, it is known that the information in the halal beef supply chain in Medan City uses blockchain technology designed with a data security system using smart contracts, where information that has been stored cannot be changed by any party. so that there is a guarantee of information security in the beef supply chain in the city of Medan. This research is expected to support transparency, security, and certainty of information about halal beef in Medan City.