Energy management is becoming a priority as organizations strive to reduce energy costs, conform to regulatory requirements, and improve their corporate image. Despite the upsurge of interest in ...energy management standards, a gap persists between energy management literature and current implementation practices. This gap can be traced to the lack of an incremental improvement roadmap. In this paper we propose an Energy Management Maturity Model that can be used to guide organizations in their energy management implementation efforts to incrementally achieve compliance with energy management standards such as ISO 50001. The proposed maturity model is inspired on the Plan-Do-Check-Act cycle approach for continual improvement, and covers well-understood fundamental energy management activities common across energy management texts. The completeness of our proposal is then evaluated by establishing an ontology mapping against ISO 50001.
•Real-world energy management activities are not aligned with the literature.•An Energy Management Maturity Model is proposed to overcome this alignment gap.•The completeness and relevance of proposed model are validated.
•The Hunt and Crossley cornerstone work on the impact modeling is revisited.•The main aspects of the dynamics of the collision between rigid bodies are addressed.•Fifteen contact force models ...developed from the Hunt and Crossley model are compared.
The selection of the contact force model plays a crucial role in the modeling and analysis of dynamical systems. The seminal work by Hunt and Crossley, published in 1975, is one of the most prominent contact force models that finds application in different areas of science and engineering. The contact force approach proposed by Hunt and Crossley has motivated and inspired a large number of researchers that, eventually, led to the publication of numerous solutions to evaluate contact forces. This paper presents an extensive collection of contact force models available in the literature that have been developed on the basis of the Hunt and Crossley's cornerstone work. The behavior of each contact force model is assessed with a simple example of application and their performance is analyzed.
Spherical joints, usually known as ball and socket joints, are utilized in several engineering applications. On the one hand, these types of joints may be found in mechanical systems acting as a ...pivot element between the wheels and the suspension in cars. On the other hand, ball and socket joints can also be used to model human articulations, as in the case of the hip and shoulder. From more simplistic to more complex scenarios, spherical joints might be modeled using different approaches. Therefore, the objective of this work is to provide a comparative analysis of different spherical joint models and to examine their influence on the dynamic response of mechanical multibody systems. For this purpose, ideal or kinematic formulation, dry, lubricated, and bushing approaches are revised. Additionally, the formulation of the dynamic equations of motion for constrained mechanical multibody systems is succinctly described. Afterward, the kinematic and dynamic characteristics of the considered spherical joint models are comprehensively described. In this regard, normal, tangential, hydrodynamic lubrication and bushing forces experienced by the multibody systems in such cases of spherical joints are examined. The application of the spherical joint models in the dynamic modeling and simulation of multibody systems is investigated. Considering two multibody models as demonstrative examples of application from the outcomes, it is observed that the influence of the spherical joint modeling strategy on the dynamic simulation of mechanical multibody systems strongly depends on the nature of the multibody model analyzed, both in terms of dynamic response and computational efficiency.
•Foot-ground contact modeling strategies for human motion analysis were reviewed.•A total of 30 contact models were included in this review.•Most studies used points, circles and 3D scanning to ...define the contact geometry.•Over 75% of studies used contact force approaches for foot-ground interaction.
This review discusses the methodologies available in the literature, usually utilized to study the foot-ground interaction in the human locomotion. For this purpose, PubMed, Web of Science and Scopus databases were considered to identify publications focusing on foot-ground contact modeling strategies. As the consequence of a critical reading of those publications, some additional papers were identified and included in the present review. A total of 30 papers were analyzed, in which different contact geometries were established with the goal of defining the foot and ground surfaces. The most common geometries were based on points, circles, ellipses, spheres, ellipsoids, rectangular contact elements and surfaces obtained from 3D scanning procedures. Regarding the resolution of the foot-ground interaction, the formulations based on contact force approaches were preferred to the methods based on geometrical constraints. Several studies considered both computational and experimental approaches. One of the main limitations reported in the analyzed papers dealt with the restriction of the motion to the sagittal plane. It was observed that a standard and general procedure to formulate the human foot-ground contact is still lacking.
Data and its valuation have gained vital significance in academia and enterprises, coinciding with diverse data valuation approaches encompassing various layers, dimensions, and characteristics. This ...paper assesses data value determination through a business capability lens based on the TOGAF standard. The paper encompasses (a) constructing a Data Valuation Business Capability (DVBC) taxonomy and (b) validating the taxonomy using two existing data valuation concepts from academia. The methodology involves information systems taxonomy development techniques backed by a previously conducted systematic literature review of 64 articles. The resultant taxonomy comprises four business capability layers, nine dimensions, and 36 characteristics. These layers and dimensions offer business, technology, and organizational perspectives, reflecting the interdisciplinary nature of data valuation alongside an enterprise architecture. Characteristics within these layers and dimensions are either exclusive or non-exclusive based on their contents. The compiled findings meet both objective and subjective quality criteria. The implications of the DVBC are multifaceted, influencing scholars and professionals alike. Scholars gain a cohesive tool enhancing transparency in the extensively debated data value domain, fostering linkages among information systems, enterprise architecture management, and data management. This empowers the progress in developing comprehensive data valuation concepts. Additionally, professionals may employ the DVBC taxonomy as a lighthouse and guiding tool, fostering internal dialog on data valuation. This entails elevating data valuation to a pivotal business capability, necessitating collaborative, regular assessment, and enhancement involving business and technological stakeholders. By adopting this taxonomy, the challenge of consistently determining data value can be effectively addressed in both academia and enterprises.
Occurrence of hyperglycemia upon infection is associated with worse clinical outcome in COVID-19 patients. However, it is still unknown whether SARS-CoV-2 directly triggers hyperglycemia. Herein, we ...interrogated whether and how SARS-CoV-2 causes hyperglycemia by infecting hepatocytes and increasing glucose production. We performed a retrospective cohort study including patients that were admitted at a hospital with suspicion of COVID-19. Clinical and laboratory data were collected from the chart records and daily blood glucose values were analyzed to test the hypothesis on whether COVID-19 was independently associated with hyperglycemia. Blood glucose was collected from a subgroup of nondiabetic patients to assess pancreatic hormones.
liver biopsies were collected to assess the presence of SARS-CoV-2 and its transporters in hepatocytes. In human hepatocytes, we studied the mechanistic bases of SARS-CoV-2 entrance and its gluconeogenic effect. SARS-CoV-2 infection was independently associated with hyperglycemia, regardless of diabetic history and beta cell function. We detected replicating viruses in human hepatocytes from
liver biopsies and in primary hepatocytes. We found that SARS-CoV-2 variants infected human hepatocytes in vitro with different susceptibility. SARS-CoV-2 infection in hepatocytes yields the release of new infectious viral particles, though not causing cell damage. We showed that infected hepatocytes increase glucose production and this is associated with induction of PEPCK activity. Furthermore, our results demonstrate that SARS-CoV-2 entry in hepatocytes occurs partially through ACE2- and GRP78-dependent mechanisms. SARS-CoV-2 infects and replicates in hepatocytes and exerts a PEPCK-dependent gluconeogenic effect in these cells that potentially is a key cause of hyperglycemia in infected patients.
A new skeletal model for the ankle joint complex Rodrigues da Silva, Mariana; Marques, Filipe; Tavares da Silva, Miguel ...
Multibody system dynamics,
2024/1, Letnik:
60, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The talocrural and the talocalcaneal articulations collectively form the ankle joint complex of the human foot and are the focus of investigation of this work. The talocrural articulation enables ...plantarflexion and dorsiflexion, while the talocalcaneal articulation allows inversion and eversion of the foot. A comprehensive analysis of the literature suggests that the ankle joint complex is modeled in different manners considering approaches with varying complexity levels, which more or less accurately mimic its intrinsic anatomical features. Several studies assume that the foot articulates with the leg via the talocrural articulation only, which is modeled as a revolute joint. Other studies consider the movements allowed by both articulations and model the ankle joint complex as spherical, revolute, or classical universal joints. Most existing approaches do not consider sufficiently accurate anatomical modeling of this joint complex. Thus, this work presents a new skeletal model for the ankle joint complex of the human foot that considers the actual anatomy and movements of the talocrural and the talocalcaneal articulations. The proposed approach uses a modified universal joint, which incorporates a massless link to mimic the actual function of the talus bone. The developed formulation is compared with a model available in the literature, which uses a classical universal joint. The outcomes show that modeling the ankle joint complex as a modified universal joint allows a more realistic representation of the anatomy of the human foot. The main differences between the two joint models are observed in the mediolateral direction.
Context: Information Technology organizations are aiming to implement DevOps capabilities to fulfill market, customer, and internal needs. While many are successful with DevOps implementation, others ...still have difficulty measuring DevOps success in their organization. As a result, the effectiveness of assessing DevOps remains erratic. This emphasizes the need to withstand management in measuring the implementation process with suitable DevOps Metrics. But what are these metrics?Objective: This research seeks to provide relevant DevOps Metrics to facilitate the efficiency of DevOps adoption and better analyze DevOps performance in enterprises.Method: A Multivocal Literature Review (MLR) is conducted, with 139 documents gathered and thoroughly examined from throughout the community, including books, scientific articles, white papers, conferences, among others.Results: This article conducts an extensive and rigorous MLR, contributing with a definition of DevOps Metrics, 22 main metrics, their definitions, importance, and categorization in sets of Key Performance Indicators, as well as exposing clear indicators on how to improve them. It is also discussed how metrics could be put into practice and what constitutes a change in the context of DevOps Metrics. The study’s outcomes will assist researchers and practitioners understand DevOps Metrics and how to better implement them.
Joints with rotational degrees of freedom, for instance, revolute, spherical, or universal joints, are commonly utilized in real-world scenarios. In the multibody systems methodology, mechanical ...joints usually are formulated as classical kinematic constraints such that there is no restriction of the range of motion (RoM) of the joint. Thus, the formulation must include additional restrictions to prevent the joints from performing unacceptable movements and to avoid unrealistic configurations of the connected bodies. Therefore, the aim of this work is to propose a methodology to restrict the RoM of mechanical joints. Joint resistance moments are applied to the bodies connected by the joint to mimic the dissipative behavior of the materials constituent of joints and to prevent unacceptable configurations of those bodies. The proposed methodology aims to extend and improve a previously published study, specifically in the definition of the RoM limits, calculation of the penalty moments, and establishment of their direction of application. Enhanced methods to deal with the detection of unacceptable joint configurations, namely the elliptical and polynomial approaches, are proposed. A parametrization procedure is described to correctly calculate the direction of the penalty moments to apply to the connected bodies. The methodology is investigated in the dynamic modeling and simulation of one demonstrative example of application, namely a simple pendulum. A parametric analysis is performed to assess the influence of the methodology parameters in the response of the model. The methodology allows the correct restriction of the RoM of joints, while preserving the mechanical energy of the system.
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