A Topology Optimization Method for Stochastic Lattice Structures

AbstractStochastic lattice structures are very powerful solutions for filling three-dimensional spaces using a generative algorithm. They are suitable for 3D printing and are well appropriate to structural optimization and mass distribution, allowing for high-performance and low-weight structures. The paper shows a method, developed in the Rhino-Grasshopper environment, to distribute lattice structures until a goal is achieved, e.g. the reduction of the weight, the harmonization of the stresses or the limitation of the strain. As case study, a cantilever beam made of Titan alloy, by means of SLS technology has been optimized. The results of the work show the potentiality of the methodology, with a very performing structure and low computational efforts

Attività ricettive amiche della bicicletta. Casi italiani e prospettive

A survey carried by the European Parliament - Directorate General for Internal Policies, entitled «The European cycle route network Eurovelo», highlights how Italy is one of the favorite tourist destinations by bicycle from other EU countries and Switzerland. The different types of tourism cycling coincide with the active tourism, nature tourism, the itinerant tourism, religious tourism, etc., but they share the use of bicycles, which requires infrastructure, services and accommodation appropriate. Regarding the latter feature can not speak of bicycle tourism without investigating the phenomenon of socalled bike hotels, accommodation facilities, not just hotel, particularly attentive to the needs of travelers cyclists, linked together in a network and offer specific the various types of bicycle tourists. The paper analyzes the totality of accommodation facilities, hotels and other, at the national, regional and provincial level, based on data from Istat 2010, identifying for each field structures bike friendly, and investigating the reasons that have led us to develop, in some areas more than in others, this type of tourist accommodation. Complete the cognitive framework an overview of local and national policies aimed at encouraging the development of this type of tourism and hotels and other accommodation facilities

The load of sustainability for Additive Manufacturing processes

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The role of cultural values in consumers’ evaluation of online review helpfulness: a big data approach

Purpose Online consumer reviews are increasingly used by third-party e-commerce organizations to shed light on the positive and negative sides of the brands they sell. However, the large number of consumer reviews requires these organizations to shortlist the most helpful ones to cope with information overload. A growing number of scholars have been investigating the determinants of review helpfulness; however, little is known about the influence of cultural factors in consumer's evaluation of review helpfulness. Design/methodology/approach This study has adopted Hofstede's cultural values framework to assess the influence of cultural factors on review helpfulness. We used a sample of 570,669 reviews of 851 hotels published by reviewers from 81 countries on Booking.com. Findings Findings reveal that reviewers from cultural contexts that score high on power distance, individualism, masculinity, uncertainty avoidance and indulgence are more likely to write helpful reviews. Originality/value This is one of the first cross-cultural studies in marketing using a big data approach in examining how users of reviews from different countries evaluate the helpfulness of online reviews

Insufficient control of blood pressure and incident diabetes

OBJECTIVE: Incidence of type 2 diabetes might be associated with preexisting hypertension. There is no information on whether incident diabetes is predicted by blood pressure control. We evaluated the hazard of diabetes in relation to blood pressure control in treated hypertensive patients. RESEARCH DESIGN AND METHODS: Nondiabetic, otherwise healthy, hypertensive patients (N = 1,754, mean +/- SD age 52 +/- 11 years, 43% women) participated in a network over 3.4 +/- 1 years of follow-up. Blood pressure was considered uncontrolled if systolic was >or=140 mmHg and/or diastolic was >or=90 mmHg at the last outpatient visit. Diabetes was defined according to American Diabetes Association guidelines. RESULTS: Uncontrolled blood pressure despite antihypertensive treatment was found in 712 patients (41%). At baseline, patients with uncontrolledblood pressure were slightly younger than patients with controlled blood pressure (51 +/- 11 vs. 53 +/- 12 years, P < 0.001), with no differences in sex distribution, BMI, duration of hypertension, baseline blood pressure, fasting glucose, serum creatinine and potassium, lipid profile, or prevalence of metabolic syndrome. During follow-up, 109 subjects developed diabetes. Incidence of diabetes was significantly higher in patients with uncontrolled (8%) than in those with controlled blood pressure (4%, odds ratio 2.08, P < 0.0001). In Cox regression analysis controlling for baseline systolic blood pressure and BMI, family history of diabetes, and physical activity, uncontrolled blood pressure doubled the risk of incident diabetes (hazard ratio [HR] 2.10, P < 0.001), independently of significant effects of age (HR 1.02 per year, P = 0.03) and baseline fasting glucose (HR 1.10 per mg/dl, P < 0.001). CONCLUSIONS: In a large sample of treated nondiabetic hypertensive subjects, uncontrolled blood pressure is associated with twofold increased risk of incident diabetes independently of age, BMI, baseline blood pressure, or fasting glucose

Hybrid technique to assess the fatigue performance of multiple cracked FSW joints

In this paper a numerical-experimental procedure useful to numerically assess the fatigue performance of friction stir welded aluminium joints is presented. The impact of manufacturing residual stresses on crack propagation in the joint driven by a remote fatigue load can be predicted. The proposed sequential procedure starts with the experimental residual stress assessment by the contour method and proceeds through the multiple crack growth simulation by the Dual Boundary Element Method. In the frame of Linear Elastic Fracture Mechanics, the superposition principle is invoked to provide the mathematical foundation supporting the proposed modelling strategy. In order to validate the proposed procedure, simple specimens are fatigue tested, obtaining multiple crack propagation scenarios that are monitored, in order to compare experimental and predicted crack growth rate

Damage assessment of different FDM-processed materials adopting Infrared Thermography

The use of components obtained through the additive manufacturing (AM) technique has become increasingly widespread in recent years, playing a central role in industrial production, and in particular in some fields such as automotive, biomedical, aerospace and electronics. Among all AM techniques, FDM (Fused Deposition Modelling) represents the most used printing technique to produce polymeric and composite components, thanks to the flexible printing process, the low cost and the diversity of the materials adopted. The aim of the present work concerns the comparison between the mechanical properties of three plastic materials printed with the FDM technique (polylactic acid PLA, polyethylene terephthalate glycol-modified PETG and Acrylonitrile-butadiene-styrene ABS) using an Original Prusa i3 MK3S, by varying the raster angle between 0°, 45° and 90° degrees. Infrared Thermography has been adopted to monitor the temperature evolution during static tensile tests and to assess stress level that can initiate damage within the material. Failure analysis was performed to correlate the mechanical behaviour with the microstructural characteristics of the materials

Insufficient control of blood pressure and incident diabetes

OBJECTIVE: Incidence of type 2 diabetes might be associated with preexisting hypertension. There is no information on whether incident diabetes is predicted by blood pressure control. We evaluated the hazard of diabetes in relation to blood pressure control in treated hypertensive patients. RESEARCH DESIGN AND METHODS: Nondiabetic, otherwise healthy, hypertensive patients (N = 1,754, mean +/- SD age 52 +/- 11 years, 43% women) participated in a network over 3.4 +/- 1 years of follow-up. Blood pressure was considered uncontrolled if systolic was >or=140 mmHg and/or diastolic was >or=90 mmHg at the last outpatient visit. Diabetes was defined according to American Diabetes Association guidelines. RESULTS: Uncontrolled blood pressure despite antihypertensive treatment was found in 712 patients (41%). At baseline, patients with uncontrolledblood pressure were slightly younger than patients with controlled blood pressure (51 +/- 11 vs. 53 +/- 12 years, P < 0.001), with no differences in sex distribution, BMI, duration of hypertension, baseline blood pressure, fasting glucose, serum creatinine and potassium, lipid profile, or prevalence of metabolic syndrome. During follow-up, 109 subjects developed diabetes. Incidence of diabetes was significantly higher in patients with uncontrolled (8%) than in those with controlled blood pressure (4%, odds ratio 2.08, P < 0.0001). In Cox regression analysis controlling for baseline systolic blood pressure and BMI, family history of diabetes, and physical activity, uncontrolled blood pressure doubled the risk of incident diabetes (hazard ratio [HR] 2.10, P < 0.001), independently of significant effects of age (HR 1.02 per year, P = 0.03) and baseline fasting glucose (HR 1.10 per mg/dl, P < 0.001). CONCLUSIONS: In a large sample of treated nondiabetic hypertensive subjects, uncontrolled blood pressure is associated with twofold increased risk of incident diabetes independently of age, BMI, baseline blood pressure, or fasting glucose

Social capital in chronic disease: an ethnographic study

Chronically ill conditions are particularly difficult to manage because of their impact both on the social and on the corporal sphere to such an extent as to involve a series of problems that negatively alter the quality of life of affected patients. Chronicity has also a considerable ef-fect on social capital. In the current literature, it is known that social capital may contribute to a range of advantages to people health. Chronic Venous Disease (CVD) includes several pathologi-cal alterations of the venous system of the lower limbs that cause a wide range of symptoms and signs. The aim of this study is to explore, with a qualitative approach, the dynamics of social cap-ital within people's experience of CVD and describe the roles of family and friends and the health care system. The method used is based on face-to-face semistructured interviews was performed, following the Consolidated Criteria for Reporting Qualitative Research (COREQ) checklist. Six-teen patients were included: 11 women and 5 men. The results obtained are completely in line with the current literature, which shows a certain difficulty in terms of daily activities, pain management; work-related difficulties; non-coverage of healthcare costs for medications and drugs prescribed. In the context of social capital, the bonding social capital of the patients inter-viewed was more positively perceived in the role of CVD management than by the patients' fami-lies. Another interesting result concerns the total absence of knowledge of patient associations with CVD. Thus, alongside the biographical destruction that CVD entails, there is evidence of the scarce relevance and presence of health policies capable of improving the quality of life of these people not only from a social and medical point of view but also from an economic point of vie