Companies face new challenges needing to find ways to stand out from the competitors. All companies face new projects, which need to be managed assertively and faster, launching new products on the ...market ahead of competitors. This strategy requires enormous dexterity and agility within teams, which are increasingly multifaceted, multidisciplinary, and multifunctional. However, teams need to conciliate apparent freedom for creation with the sustainability rules, which are increasingly demanding, such as legislation and image that companies want to pass on to the market in terms of corporate social responsibility, ensuring a sustainable development of the companies. The goal of this work is to investigate and correlate agile project management and sustainability, taking into account that there are strong relationships, as well as to learn how agile project management affects organization's social, environmental, and economical dynamics from the triple bottom line standpoint. The research examines how agile project management ideas are connected to the triple bottom line concepts based on the literature. The framework was based on the theoretical assumptions underpinning the present research. The basic structure of the developed framework is based on the framework of a matrix‐based method for ordering and synthesizing data. Thus, network diagrams have been developed reproducing the links existing in the literature, both explicitly and implicitly. However, they were deeply expanded considering links not previously referred in the literature. An explanation about these new links is also provided, justifying their inclusion. Hence, the new diagrams offer a more complete landscape about how the adoption of agile practices in project management can improve sustainability in its different aspects, and vice‐versa. The findings reveal that implementing agile project management induces direct effects on an organization's social, economic, and environmental dynamics of the companies, as well as in their teams, with a favorable effect on all of them.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Microscale abrasion has been intensively used to study the wear behavior o several hard coatings, enabling the observation of different wear mechanisms. Recently, a study arguing whether the surface ...texture of the ball could influence the dynamics of abrasive particles throughout the contact was presented. In this work, the influence of the abrasive particles concentration able to change the texture of the ball was studied to understand its influence on the wear modes-rolling or grooving. Thus, tests were carried out using samples with a thin coating of TiN, deposited using the Physical Vapor Deposition (PVD) technique, and AISI 52100 steel balls etched over 60 s to induce a change in their texture and roughness were used. Three abrasive slurries were prepared with black silicon carbide (SiC) particles (average particle size of 4 μm) with different concentrations, 0.25, 0.35, and 0.45 g/cm
. The rotation speed used in the tests was 80 rpm and the normal loads applied in the study were 0.2 N and 0.5 N, and 1 N. After the wear tests, the coated samples and tracks on the surface of the balls were observed by SEM and 3D microscopy to understand the abrasive particle dynamics, evaluating the wear mode transition as well as the function of both applied load and slurry concentration. The tracks in the balls showed particles embedded on their surface. A lower concentration of abrasion was conducted to higher specific wear rate. Moreover, a predominant two-body wear mechanism was induced when the abrasive concentration was increased. There was an increase in the roughness of the scar and the surface of the balls with an increase in the abrasive particles' concentration.
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•Method for KC detection in human sleep EEG based on multitaper spectral analysis.•The time complexity of method is O(N·logN).•The method was evaluate using a commonly public database, ...DREAMS.•Maximum recall of 85.10%; maximum precision of 71.88%.•The method outperform five existing methods in terms of F1 and F2 scores.
In this paper, we propose a novel method for automatic k-complex (KC) detection in human sleep EEG, named MT-KCD. KCs are slow oscillations in the EEG signal characterized by a well-delineated, negative, sharp waves immediately followed by a positive component standing out from the background, with high-amplitude and total duration ≥ 0.5 s. Among the important aspects of the KC are its homeostatic and reactive functions in the brain, functioning as a sleep protection mechanism, and its practical use as a marker of N2 sleep stage during sleep studies. Given the importance of the KC, and the effort required from human experts to analyze EEG recordings visually, some recent research works have proposed automatic methods for KC detection. In comparison with existing methods, a key feature and novelty of MT-KCD is the use of multitaper spectral analysis to pre-process the EEG signal and automatically extract candidate KCs from it (characterized as 0-4 Hz power concentrations standing out from the background). After extraction, candidates are accepted/rejected depending on time domain characteristics (peak-to-peak amplitude ≥ 75 µV, duration ≤ 2 s). The method overall time complexity is O(N·logN). Regarding effectiveness, we have evaluated MT-KCD by using a public KC database (DREAMS) consisting of ten polysomnographic recordings of healthy patients (6 female and 4 male subjects with age range 20–47 years) partially annotated by two experts. Results have shown that MT-KCD improves detection metrics, especially F1 and F2 scores (harmonic averages of recall and precision), when compared to existing methods. Besides, improving F1 and F2 scores, MT-KCD also contributes to the automatic analysis of sleep EEG multitaper spectrograms, a technique recently proposed by researchers in the area of sleep studies as a complement to the traditional hypnogram (sleep stages diagram).
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The use of disinfection and cleaning chemicals in several municipal facilities, such as swimming pools and drinking water treatment plants, causes the degradation of various types of wood, which ...leads to failures in equipment and the corresponding need for maintenance. This degradation creates added costs for municipalities, as well as the closure of certain facilities due to curative or preventive maintenance and, in many cases, public health issues, due to the water being contaminated with deteriorating products. Through a thorough study of the degradation effect on the products, more resistant materials can be found which are able to withstand these adversities and increase the lifespan of wood in regular contact with chemical agents. This is achievable by the determination of the cost-effectiveness of the substitute material to replace these components with alternative ones, with properties that better resist the deterioration effects promoted by aggressive environments. No studies have been found so far strictly focused on this matter. The objective of this study is to evaluate the degradation presented by two types of wood, beech and oak, which are exposed to the action of chlorine in municipal facilities. This degradation varies according to the chlorine content and the materials' time of contact with the chemical agent, allowing the selection of new materials which will provide an extended lifetime of the components, reducing maintenance drastically, as well as costs for the facilities and the risk to public health. The performed experimental tests have shown that the oak wood has the best results regarding chlorine degradation resistance.
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The machining process is still a very relevant process in today’s industry, being used to produce high quality parts for multiple industry sectors. The machining processes are heavily researched, ...with the focus on the improvement of these processes. One of these process improvements was the creation and implementation of tool coatings in various machining operations. These coatings improved overall process productivity and tool-life, with new coatings being developed for various machining applications. TiAlN coatings are still very present in today’s industry, being used due to its incredible wear behavior at high machining speeds, high mechanical properties, having a high-thermal stability and high corrosion resistance even at high machining temperatures. Novel TiAlN-based coatings doped with Ru, Mo and Ta are currently under investigation, as they show tremendous potential in terms of mechanical properties and wear behavior improvement. With the improvement of deposition technology, recent research seems to focus primarily on the study of nanolayered and nanocomposite TiAlN-based coatings, as the thinner layers improve drastically these coating’s beneficial properties for machining applications. In this review, the recent developments of TiAlN-based coatings are going to be presented, analyzed and their mechanical properties and cutting behavior for the turning and milling processes are compared.
Climate change is projected to increase flood risks in western Africa. In the FANFAR project, a pre-operational flood early warning system (FEWS) for western Africa was co-designed in workshops with ...50–60 stakeholders from 17 countries, adopting multi-criteria decision analysis (MCDA). We aimed at (i) designing a FEWS with western African stakeholders using MCDA and (ii) evaluating participatory MCDA as a transdisciplinary process. To achieve the first aim (i), we used MCDA methods for problem structuring and preference elicitation in workshops. Problem structuring included stakeholder analysis, creating 10 objectives to be achieved by the FANFAR FEWS and designing 11 possible FEWS configurations. Experts predicted FEWS configuration performance, which we integrated with stakeholder preferences. We tested MCDA results in sensitivity analyses. Three FEWSs showed good performance, despite uncertainty, and were robust across different preferences. For stakeholders it was most important that the FEWS produces accurate, clear, timely, and accessible flood risk information. To achieve the second aim (ii), we clustered common characteristics of collaborative governance frameworks from the sustainability science and transdisciplinary literature. Our framework emphasizes issues crucial to the earth systems sciences, such as uncertainty and integrating interdisciplinary knowledge. MCDA can address both well. Other strengths of MCDA are co-producing knowledge with stakeholders and providing a consistent methodology with unambiguous, shared results. Participatory MCDA including problem structuring can contribute to co-designing a project but does not achieve later phases of transdisciplinary processes well, such as co-disseminating and evaluating results. We encourage colleagues to use MCDA and the proposed framework for evaluating transdisciplinary hydrology research that engages with stakeholders and society.
Machining processes remain an unavoidable technique in the production of high-precision parts. Tool behavior is of the utmost importance in machining productivity and costs. Tool performance can be ...assessed by the roughness left on the machined surfaces, as well as of the forces developed during the process. There are various techniques to determine these cutting forces, such as cutting force prediction or measurement, using dynamometers and other sensor systems. This technique has often been used by numerous researchers in this area. This paper aims to give a review of the different techniques and devices for measuring the forces developed for machining processes, allowing a quick perception of the advantages and limitations of each technique, through the literature research carried out, using recently published works.
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Due to chlorine’s ability to kill bacteria and fungi through a chemical reaction, chlorine solutions are commonly used to clean and disinfect numerous public facilities, although these actions are ...also dependent to the equipment present in those facilities. Accordingly, the interest in studying its effect when in contact with different materials is obvious. This study was carried out through accelerated degradation tests and various analysis methods (optical microscope, scanning electron microscope, and tensile tests). The objective was to observe the wear presented by three polymeric materials, polyvinyl chloride (PVC), high-density polyethylene (HDPE), and polypropylene (PP), when exposed to chlorine’s action in swimming pools and drinking water treatment plants. The resulting effect depends on the chlorine content and the type of contact between the chemical agent and the material. The aim was to select the material less likely to be affected by chlorine through tests and analyses, allowing a longer component life. The use of certain more resistant polymeric materials can drastically reduce maintenance, reducing fundamental factors such as costs, the downtime of municipal facilities, and also the risk to public health. It was concluded that PVC has the most stable behaviour overall when in contact with chlorine solutions.
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•Mentha essential oils are rich in oxygenated monoterpenes.•The better antioxidant essential oils present piperitenone oxide as the major constituent.•Mentha spicata (Ciudad del Leste ...mint), which showed the best antifungal activity, contains pulegone as main constituent.
The plants of the genus Mentha are widely used in cooking, cosmetics and popular medicine. The present work analyzes the chemical composition of the essential oils of several Mentha species, and evaluates some functional properties such as antioxidant, anticholinesterase and antifungal, to corroborate their medicinal use. The oils obtained by hydrodistillation showed higher levels of the monoterpenes limonene, isomenthone, menthol, menthofuran, d-neoisomenthol, 1,8-cineole (eucalyptol), d-carvone, linalool, linalyl acetate, piperitenone oxide and pulegone. The essential oil of Mentha longifolia (Himalayan silver mint) stood out for its antioxidant activity with IC50 of 0.86±0.01mg/mL by the DPPH method and 0.64±0.02mg/mL by the method of β-carotene/linoleic acid system. Mentha piperita oils (chocolate mint) and Mentha spicata (menthol mint) showed good inhibition of acetylcholinesterase, with enzyme inhibition zones of 1.0cm and 0.9cm, respectively. The antifungal activity of Mentha essential oils showed moderate activity against Trichophyton rubrum and Microsporum canis, and the oil of M. spicata (Ciudad del Leste mint) showed MIC and MFC near to the control. The major components of the essential oils could be responsible for evaluated activities, which are associated with the medicinal properties reported for Mentha species.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Laser technology plays an important role in today’s industrial environment. Laser marking is typically used at the end of the production chain to personalize products and make them traceable to the ...point of sale. One of the challenges of laser marking is the difficulty of creating contrasts whose reflectivity can cause readability problems for electronic decoding devices on production lines, known as scanners. This problem is related to the wrong choice of marking parameters, which results in waste for companies in terms of production stoppages due to rejection, scrap, and customer complaints. Although these problems are common, this process is increasingly used in the industry. Therefore, there is a gap in studies in this field to optimize the marking parameters in many materials, such as PBT (polybutylene terephthalate). The present work was developed in a final assembly line of instrument clusters for motorcycles, where tests were carried out with different types of laser marking parameters, through the implementation of a factorial DoE, with a specific type of laser and material. The laser-marked codes were analyzed in a laboratory using a verifier to assess quality according to ISO/IEC 29158:2020. It was found that the lower the parameter values, the poorer the quality of the codes. The data were statistically processed, and it was possible to identify the marking parameters that ensured the best quality and process performance for DMC and QR codes.
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