Herein, modern green synthesis approaches are studied to assemble N-heterylarenes scaffolds via a non-catalyzed intramolecular 5/6-exo-dig cyclocondensation reaction based on the in-situ generation of arenehydrazonopentan-/hexan-2-one. Accordingly, the formation of two N-heteryl moieties, pyrazol-1-yl and pyridazin-1(4H)-yl, was initially studied. Therefore, appropriate fluorophenyl was first converted into their respective phenylhydrazine by SNAr reaction and then reacted with different trigonal carbonyl bielectrophiles (-CO-, -CO₂R, and -CO₂H) in ethanol in the presence of US, MW, IR, and an IR· US irradiation mixture. Cyclic nitrogenous cores were best obtained when subjected to microwave irradiation with ketone and arylhydrazine as starting reagents, allowing them to get excellent yields quickly. Arylhydrazine reactants featuring Π-donor groups underwent the best 5/6-exo-dig type annulment reaction. Presumably, the observed improvements in EDG-dependent reaction efficiency reflect changes in the nucleophilicity of arylhydrazines intermediates as α-nucleophilic reactants.

The effect of air injection into a coffee roasting chamber of a 2 kg rotary drum roaster is investigated on the temperature profiles and organoleptic properties of a Catuai coffee variety. In the experimental study, 1 kg of coffee beans were used and the air injection velocities were varied for the cases of 0 (standard roasting design), 1, 2 and 3 m/s; testing in triplicate and the two most representative were taken. In the coffee roaster, the temperature was monitored simultaneously in the air inlet duct, roasting chamber and gas outlet duct. The organoleptic properties were examined by a group of professionals from Negociaciones Agroindustrial Arévalo S.A. NARSA in the province of Chanchamayo - Peru, which has a G4 laboratory certified by the Specialty Coffee Association (SCA). In the organoleptic ratings, a maximum score of 83.21/100 was found for the 2 m/s test and a minimum of 80.63/100 for the 1 m/s test. For the numerical characterization, the principle of fluid mechanics such as turbulent regime flow and energy transport were used by the finite volume (FV) method using SolidWorks 2021 Flow Simulation software. The numerical results showed that for the 2 m/s test, the temperature of the bean reaches 195 oC at 500 s, indicating that the whole coffee bean reaches the cooking temperature required for the development time prior to eviction; while for the 1 m/s test, it did not exceed 190 oC. It is shown here that the effect of air injection in the roasting chamber, caused organoleptic changes with respect to the conventional design without air injection, due to a sustained cooking at different times and an adequate development time. However, there is a speed threshold where when exceeded, temperatures inside the chamber remain low, development time is extended (machine energy consumption is extended), and organoleptic properties should not improve. However, as the test speeds are exceeded, temperatures inside the chamber remain low, causing the development time to be extended with higher energy consumption and under these conditions the organoleptic properties are not improved.

Fatigue crack growth studies require models that accurately predict component life with low uncertainty. Despite the large number of proposed models, there is no clarity on their applicability, which justifies a comparative analysis between some of them. The dual boundary element method (DBEM) was applied for cracked bodies, whereby the stress intensity factors (SIF), the growth rate, and the number of cycles were computed. Three crack increment models were studied under constant amplitude fatigue loads: the Paris, the Klesnil-Lucas, and the Forman models. Results were validated with experimental literature and through the finite element method, indicating that each model represents a specific zone of the crack growth curve. Klesnil-Lucas model reproduces the region near the fracture threshold, Paris fits the controlled crack growth zone, whereas Forman’s model recreates the unstable fracture zone, i.e., when the stress intensity factor approaches the material’s fracture toughness. The J-integral with stress field decomposition gave errors below 0.8% for mode I. Results were similar for the propagation path and the number of cycles to those obtained with the finite element method, with errors of about 3% considering different K-effective approaches. Klesnil-Lucas accurately predicts the number of cycles with an error margin below 3%, considering the curved region in the growth rate at the propagation onset, while the Paris model becomes very conservative, predicting values up to 50% lower than experimental data. The Klesnil-Lukas model is advised for simulating the entire crack propagation.

Even though entrepreneurial firms make substantial contributions to both domestic and global economies and innovations, there is disagreement in the literature regarding how open innovation affects these firms' ability to succeed. The current research is an attempt to address the gaps by analyzing the intricacies and dynamics of entrepreneurial firms’ involvement in Open Innovation. Furthermore, the impact on performance is examined from a knowledge perspective. In Jordanian context, this study analyzed the link between stakeholder interactions, knowledge management, open innovation, and the performance of entrepreneurial firms. The findings demonstrated that open innovation activities are statistically significant to the overall performance of entrepreneurial firms. However, since it has an unintentional detrimental effect over the performance of entrepreneurial firms in Jordan, the moderating effect of stakeholder relations and the mediation effect of knowledge management has been analyzed. The moderating role of stakeholder relationships has been proven statistically which enriched the theoretical foundations of RBV and contingency theory by adding stakeholders’ theory into the combination of the two theories, at the end limitations and guidelines for future research along with practical implications are emphasized.

Maintenance philosophies and their activities have always been a major concern in industry. So, every industrial complex needs a clear and comprehensive maintenance plan to keep its equipment reliable and available. In this study, we proposed an AHP model combined with the BOCR method to select the most reliable maintenance strategy for a combined cycle power plant (GTG-HRSG). Five well-known maintenance alternatives including root cause analysis, condition-based maintenance, reliability-centered maintenance, run-to-failure and preventive maintenance are chosen to be evaluated by several experts from various departments of operation, planning and maintenance via three priorities of economic, technical and operation and 30 sub criteria and controls. Then, five different BOCR synthesize methods have been utilized to rank maintenance alternatives. The final result shows that four out of five synthesize methods have ranked RCA as the top maintenance strategy and RCM as second. In one other method, the rank of these two strategies is vice versa.

Current organizations need to create advantages by measuring and developing intangible resources. Business intelligence and knowledge management help to achieve it. On the other hand, virtual teams have problems that make the regularization of their work processes and their social interaction methods difficult and restrict the team members to unfold efficiently. Knowledge management purposes skills from structural capital and human capital and it is believed to solve these types of problems in virtual teams. This research has the objective to identify the best practices and opportunity areas for the intelligent management of virtual teams by showing practical suggestions in the discussion built with the inferential statistics testing of five hypotheses. The results indicate that three hypotheses were accepted while two were rejected.

The contamination of water bodies in the Peruvian Amazon, particularly in the Madre de Dios region, has increased significantly due to illegal mining activities that severely impact human health and ecosystems. This issue is exacerbated by the lack of effective tools for monitoring and managing water bodies, which could help mitigate negative effects and ensure their preservation. In this study, water bodies were identified using machine learning and satellite image analysis from the area known as 'La Pampa', a zone severely affected by illegal mining located between kilometers 98 and 115 of the Interoceanic Highway in the Madre de Dios region, Peru. Using Google Earth Engine, 600 satellite images were collected and classified into three categories: water bodies (200), soil (200), and vegetation (200). Models such as Random Forest, K-Nearest Neighbors, Support Vector Machines, and a Multilayer Perceptron were trained and validated. The results show that the K-Nearest Neighbors model achieved the best performance, with a precision of 92.58%, recall of 92.74%, F1-Score of 92.61%, and an accuracy of 92.49%, outperforming the other evaluated models. These findings highlight the feasibility of combining machine learning with satellite images for the management of water resources in affected areas, offering a valuable tool for environmental decision-making.

This paper develops an economic production quantity (EPQ) inventory model with rework process for a single stage production system with one machine. The existence of a unique machine results in limited production capacity. The aim of this research is to determine both the optimal cycle length and the optimal production quantity for each product to minimize the expected total cost (holding, production, setup, rework costs). The convexity of the inventory model is derived. Also the objective function is proved to be convex. The proposed inventory model is validated with illustrating numerical examples and the optimal period length and the total system cost are analyzed.

Recently, the economic lot scheduling problem (ELSP) with common cycle time and shelf life restrictions has attracted the attention of several researchers. In this paper, a comparative study of solutions given by Xu and Sarker (2003) [Computers & Operations Research 30 (6), 925-938] with the results given by Viswanathan and Goyal (2000) [International Journal of Production Research, 38 (4), 829-836] are presented. Additionally, the paper makes some observations about two mathematical expressions, which contain a technical shortcoming.