TEACHING TECHNICAL DESIGN SPECIFICATIONS IN PRODUCT REDESIGN PROCESSES USING THE FBS MODEL

Establishment of technical design specifications for the redesign of technical systems, which are not derived from customers needs, relies heavily on designers intuition and experience. The very few methods proposed in the literature for the establishment of such technical design specifications hinders the learning process in conceptual design subjects. The objective of this article is to propose a structured method for identification of technical design specifications based on the function-behaviorstate (FBS) model applied on redesign tasks. The method is being taught to students on the course of methodical' design in order to develop their abilities on the identification of technical specifications without relying on previous knowledge on the system and relying more on detailed observation. This method is based on the observation and identification of the different states taken by the attributes of the entities conforming the system (i.e., flows-function carriers-environment). A small scale preliminary study was conducted in order to validate the initial performance of the proposed method. Eight groups made up of undergraduate mechanical engineering students with basic knowledge in conceptual design were instructed to identify technical design specifications. The redesign task was to create an automated solution for replacing the manual production process at small food manufacturing companies. Four groups of students had to establish the specifications using their experience while the other four groups had to use the proposed method. Initial results showed for the proposed method a 36% increase in the number of identified specifications

TEACHING TECHNICAL DESIGN SPECIFICATIONS IN PRODUCT REDESIGN PROCESSES USING THE FBS MODEL

Establishment of technical design specifications for the redesign of technical systems, which are not derived from customers needs, relies heavily on designers intuition and experience. The very few methods proposed in the literature for the establishment of such technical design specifications hinders the learning process in conceptual design subjects. The objective of this article is to propose a structured method for identification of technical design specifications based on the function-behaviorstate (FBS) model applied on redesign tasks. The method is being taught to students on the course of methodical' design in order to develop their abilities on the identification of technical specifications without relying on previous knowledge on the system and relying more on detailed observation. This method is based on the observation and identification of the different states taken by the attributes of the entities conforming the system (i.e., flows-function carriers-environment). A small scale preliminary study was conducted in order to validate the initial performance of the proposed method. Eight groups made up of undergraduate mechanical engineering students with basic knowledge in conceptual design were instructed to identify technical design specifications. The redesign task was to create an automated solution for replacing the manual production process at small food manufacturing companies. Four groups of students had to establish the specifications using their experience while the other four groups had to use the proposed method. Initial results showed for the proposed method a 36% increase in the number of identified specifications

WHO O2CoV2: oxygen requirements and respiratory support in patients with COVID-19 in low-and-middle income countries—protocol for a multicountry, prospective, observational cohort study

Introduction SARS-CoV-2 has been identified as the cause of the disease officially named COVID-19, primarily a respiratory illness. COVID-19 was characterised as a pandemic on 11 March 2020. It has been estimated that approximately 20% of people with COVID-19 require oxygen therapy. Oxygen has been listed on the WHO Model List of Essential Medicines List and Essential Medicines List for Children for almost two decades. The COVID-19 pandemic has highlighted, more than ever, the acute need for scale-up of oxygen therapy. Detailed data on the use of oxygen therapy in low-and-middle income countries at the patient and facility level are needed to target interventions better globally.Methods and analysis We aim to describe the requirements and use of oxygen at the facility and patient level of approximately 4500 patients with COVID-19 in 30 countries. Our objectives are specifically to characterise type and duration of different modalities of oxygen therapy delivered to patients; describe demographics and outcomes of hospitalised patients with COVID-19; and describe facility-level oxygen production and support. Primary analyses will be descriptive in nature. Respiratory support transitions will be described in Sankey plots, and Kaplan-Meier models will be used to estimate probability of each transition. A multistate model will be used to study the course of hospital stay of the study population, evaluating transitions of escalating respiratory support transitions to the absorbing states.Ethics and dissemination WHO Ad Hoc COVID-19 Research Ethics Review Committee (ERC) has approved this global protocol. When this protocol is adopted at specific country sites, national ERCs may make require adjustments in accordance with their respective national research ethics guidelines. Dissemination of this protocol and global findings will be open access through peer-reviewed scientific journals, study website, press and online media.Trial registration number NCT04918875

A survey on static and quasi-static finite element models of the human cervical spine

Finite element analyses are an important source of information on the biomechanical behaviour of the cervical spine; as well as an important tool in the design and evaluation of spinal instrumentation. This article presents a comprehensive survey of the finite element models of the cervical spine that have been used to study its pathological/nonpathological biomechanics under static/quasi-static loading conditions. Publications that met the inclusion criteria were analysed to extract parameters relative to model identification (e.g., spine segment, population, utility, limitations), model structure (e.g., loading/boundary conditions, anatomical structures, constitutive representation), simulation structure (e.g., software), verification (e.g., convergence) and validation (e.g., validated procedure/output, assumptions). Besides summarizing different modelling approaches with their associated parameters, this article outlines generalities and issues related to the obtainment of such models. The survey shows that authors often fail to report parameters that are critical for the reproducibility of results and that, even with fully reported parameters, these models are inherently difficult to replicate because they generally are patient-specific with their geometry based on data from in-house specimens/subjects. Overall, while the survey contributes to an understanding of the implications of following different modelling approaches and allows to take advantage of previously developed models, further research is required to improve the accuracy and utility of these models. © 2017, Springer-Verlag France SAS, part of Springer Nature