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Deep Learning-based Aerial Image Segmentation with Open Data for Disaster Impact Assessment
No full textSatellite images are an extremely valuable resource in the aftermath of natural disasters such as hurricanes and tsunamis where they can be used for risk assessment and disaster management. In order to provide timely and actionable information for disaster response, in this paper a framework utilising segmentation neural networks is proposed to identify impacted areas and accessible roads in post-disaster scenarios. The effectiveness of pretraining with ImageNet on the task of aerial image segmentation has been analysed and performances of popular segmentation models compared. Experimental results show that pretraining on ImageNet usually improves the segmentation performance for a number of models. Open data available from OpenStreetMap (OSM) is used for training, forgoing the need for time-consuming manual annotation. The method also makes use of graph theory to update road network data available from OSM and to detect the changes caused by a natural disaster. Extensive experiments on data from the 2018 tsunami that struck Palu, Indonesia show the effectiveness of the proposed framework. ENetSeparable, with 30% fewer parameters compared to ENet, achieved comparable segmentation results to that of the state-of-the-art networks
Randomised phase 3 study of ivosidenib in IDH1-mutant chemotherapy-refractory cholangiocarcinoma
No full textBackgroundIsocitrate dehydrogenase 1 (IDH1) mutations occur globally in approximately 13% of patients with intrahepatic cholangiocarcinoma, a relatively uncommon cancer with a poor clinical outcome. This global phase 3 study was conducted to assess the efficacy and safety of ivosidenib (AG-120)—a small-molecule targeted inhibitor of mutated IDH1 (mIDH1)—in previously treated mIDH1 cholangiocarcinoma.MethodsIn this double-blind study, patients aged ≥18 years with histologically confirmed mIDH1 advanced cholangiocarcinoma who progressed on prior therapy were randomised 2:1 to ivosidenib 500 mg once daily or matched placebo, using an interactive web-based response system. These patients constituted the intent-to-treat analysis set (ITT) used for the primary efficacy analyses. Additional key eligibility criteria included ≤2 prior treatment regimens for advanced disease; an Eastern Cooperative Oncology Group Performance Status score of 0 or 1; and a measurable lesion as defined by Response Evaluation Criteria in Solid Tumors version 1·1. Placebo-to-ivosidenib crossover was permitted upon radiographic progression per investigator assessment. Patients were enrolled and treated at participating study centres on an outpatient basis. Safety was assessed in all patients who received ≥1 dose of ivosidenib. The primary endpoint was progression-free survival (PFS) by independent central review. Enrolment is complete; this study is registered with ClinicalTrials.gov, NCT02989857.FindingsRecruitment occurred between Feb 20, 2017 and Mar 1, 2019. As of the Jan 31, 2019, data cut, 185 patients were randomised to ivosidenib (n=124) or placebo (n=61). Ivosidenib significantly improved median PFS compared with placebo (2·7 vs 1·4 months; hazard ratio [HR] 0·37; 95% CI 0·25–0·54; one-sided p<0·0001). Six- and 12-month PFS rates for ivosidenib were 32% (95% CI 23–42) and 22% (13–32), respectively. No placebo-treated patients had a PFS ≥6 months. Median overall survival (OS) was 10·8 months (95% CI 7·7–17·6) for ivosidenib and 9·7 months (4·8–12·1) for placebo (HR 0·69 [0·44–1·10]; one-sided p=0·06). The median follow-up was 6·9 months (IQR 2·8–10·9) for PFS by independent central review and 8·8 months (4·5–13·6) for OS. The most common grade ≥3 adverse event in both treatment groups was ascites (4 [7%] of 59 placebo patients and 9 [7%] of 121 ivosidenib patients). Serious adverse events were reported in 36 ivosidenib patients and 13 placebo patients. There were no treatment-related deaths.InterpretationIvosidenib improved PFS compared with placebo, and was well tolerated. This study demonstrates the clinical benefit of targeting mIDH1 in advanced mIDH1 cholangiocarcinoma
Efficacy and safety of dupilumab with concomitant topical corticosteroids in children 6 to 11 years old with severe atopic dermatitis: a randomized, double-blinded, placebo-controlled phase 3 trial
No full textBackground: Children with severe atopic dermatitis (AD) have limited treatment options. Objective: We report efficacy and safety of dupilumab + topical corticosteroids (TCS) in children aged 6–11 years with severe AD inadequately controlled with topical therapies. Methods: In this double-blind, 16-week, phase 3 trial (NCT03345914), 367 patients were randomized 1:1:1 to 300mg dupilumab every 4 weeks (300mg-q4w), a weight-based regimen of dupilumab every 2 weeks (100mg-q2w, baseline weight <30kg; 200mg-q2w, ≥30kg), or placebo; with concomitant medium-potency TCS. Results: Both the q4w and q2w dupilumab+TCS regimens resulted in clinically meaningful and statistically significant improvement in signs, symptoms, and quality of life (QoL) versus placebo+TCS in all prespecified endpoints. For q4w/q2w/placebo, 32.8%/29.5%/11.4% of patients achieved Investigator’s Global Assessment scores of 0/1; 69.7%/67.2%/26.8% achieved ≥75% improvement in Eczema Area and Severity Index scores; and 50.8%/58.3%/12.3% achieved ≥4-point reduction in worst itch score. Response to therapy was weight-dependent: optimal dupilumab doses for efficacy and safety were 300mg-q4w in children <30kg and 200mg-q2w in children ≥30kg. Conjunctivitis and injection-site reactions were more common with dupilumab+TCS than placebo+TCS. Limitations: Short-term 16-week treatment period; severe AD only. Conclusion: Dupilumab+TCS is efficacious and well tolerated in children with severe AD, significantly improving signs, symptoms, and QoL
Attitude control for satellites flying in VLEO using aerodynamic surfaces
No full textThis paper analyses the use of aerodynamic control surfaces, whether passive or active, in order to carry out very low Earth orbit (VLEO) attitude maneuver operations.Flying a satellite in a very low Earth orbit with an altitude of less than 450 km, namely VLEO, is a technological challenge. It leads to several advantages, such as increasing the resolution of optical payloads or increase signal to noise ratio, among others. The atmospheric density in VLEO is much higher than in typical low earth orbit altitudes, but still free molecular flow. This has serious consequences for the maneuverability of a satellite because significant aerodynamic torques and forces are produced. In order to guarantee the controllability of the spacecraft they have to be analyzed in depth. Moreover, at VLEO the density of atomic oxygen increases, which enables the use of air-breathing propulsion (ABEP). Scientists are researching in this field to use ABEP it as a drag compensation system, and consequently an attitude control based on aerodynamic control could make sense. This combination of technologies may represent an opportunity to open new markets.In this work, several satellite geometric configurations were considered to analyze aerodynamic control:3 axis control with feather configuration and 2 axis control with shuttlecock configuration.The analysis was performed by simulating the attitude of the satellite as well as the disturbances affecting the spacecraft. The models implemented to simulate the disturbances were the following: Gravitational gradient torque disturbance, magnetic dipole torque disturbance (magnetic field model IGRF12), and aerodynamic torque disturbances (aerodynamic model DTM2013 and wind model HWM14).The maneuvers analyzed were the following: detumbling or attitude stabilization, pointing and demisability. Different VLEO parameters were analyzed for every geometric configuration and spacecraft maneuver. The results determined which of the analyzed geometric configurations suits better for every maneuver. This work is part of the H2020 DISCOVERER project. Project ID 737183
Global prevalence of irritable bowel syndrome: time to consider factors beyond diagnostic criteria?
No full textAI Feel You:Customer Experience Assessment via Chatbot Interviews
No full textPurpose: While customer experience (CE) is recognized as a critical determinant of business success, both academics and managers are yet to find a means to gain a comprehensive understanding of CE cost-effectively. We argue that the application of relevant artificial intelligence (AI) technology could help address this challenge. Employing interactively prompted narrative storytelling, we investigate the effectiveness of sentiment analysis (SA) on extracting valuable CE insights from primary qualitative data generated via chatbot interviews.Design/methodology/approach: Drawing on a granular and semantically clear framework we developed for studying CE feelings, an AI-augmented chatbot was designed. The chatbot interviewed a crowdsourced sample of consumers about their recalled service experience feelings. By combining free-text and closed-ended questions, we were able to compare extracted sentiment polarities against established measurement scales and empirically validate our novel approach.Findings: We demonstrate that SA can effectively extract CE feelings from primary chatbot data. Our findings also suggest that further enhancement in accuracy can be achieved via improvements in the interplay between the chatbot interviewer and SA extraction algorithms.Research limitations/implications: The proposed customer-centric approach can help service companies to study and better understand CE feelings in a cost-effective and scalable manner. The AI-augmented chatbots can also help companies foster immersive and engaging relationships with customers. Our study focuses on feelings, warranting further research on AI’s value in studying other CE elements.Originality/value: The unique inquisitive role of AI-infused chatbots in conducting interviews and analyzing data in realtime, offers considerable potential for studying CE and other subjective constructs
Can Projects be Processual? A Perspective from Ethics in Stakeholder Engagement for Project Sustainability
No full textIt is a research standard to have theories underpinning research. Conceptually, we often read about the theoretical framework as the theoretical skeleton of the research, which can be referred to as the framework of research. This pattern always becomes substantial issues at PhD VIVA (thesis submission), conferences or journal discussions. Theories have been applied in different context; empirical data have been applied in support of theories in different contextual settings. Gaps in researches have sometimes been because of application of theories or methods in different context. When a study lacks theory, the context, imagination and argument are lost. However, process theory (as a theory or philosophy) has not gained considerable attention from authors in project management in general, and has received little or no authors’ attention in infrastructure project management and implementation in particular. Furthermore, there is not yet any evidence of process application in the ethics domain of infrastructure project management. This paper, using an empirical (on-going), constructivist interpretivist approach to study ethics in stakeholder engagement for project sustainability, will contribute to knowledge by deductively establishing the applicability of process theory framing into the project management environment alongside with ethics and stakeholder theories
UTILISING PATIENT AND PUBLIC INVOLVEMENT IN STATED PREFERENCE RESEARCH IN HEALTH: LEARNING FROM THE EXISTING LITERATURE AND A CASE STUDY
No full textPublications reporting discrete choice experiments of healthcare interventions rarely discuss whether patient and public involvement (PPI) activities have been conducted. This paper presents examples from the existing literature and a detailed case study from the NIHR funded PATHWAY programme which comprehensively included PPI activities at multiple stages of preference research. Reflecting on these examples, as well as the wider PPI literature, we describe the different stages at which it is possible to effectively incoporate PPI across preference research, including the design, recruitment, and dissemination of projects. Benefits of PPI activities include gaining practical insights from wider perspective, which can positively impact experiment design as well as survey materials. Further benefits included advice around recruitment and reaching a greater audience with dissemination activities, amongst others. There are challenges associated with PPI activities; examples include time, cost and outlining expectations. Overall, although we acknowledge practical difficulties associated with PPI, this work highlights that it is possible for preference researchers to implement PPI across preference research. Further research systematically comparing methods related to PPI in preference research and their associated impact on the methods and results of studies would strengthen the literature
Synthesis of Solar Photovoltaic Systems: Optimal Sizing Comparison
No full textIn the current scenario, energy demand rises by 1.3% each year to 2040, and photovoltaic (PV) systems have emerged as an alternative to the fossil or nuclear fuel energy generation. The use of formal methods for PV systems is a new subject with significant research spanning only five years. Here we develop and evaluate an automated synthesis technique to obtain optimal sizing of PV systems based on Life Cycle Cost (LCC) analysis. The optimal solution is the lowest cost from a list of equipment that meets the electrical demands from a house, plus the replacement, operation, and maintenance costs over 20 years. We propose a variant of the counterexample guided inductive synthesis (CEGIS) approach with two phases linking the technical and cost analysis to obtain the PV sizing optimization. We advocate that our technique has various advantages if compared to off-the-shelf optimization tools available in the market for PV systems. Experimental results from seven case studies demonstrate that we can produce an optimal solution within an acceptable run-time; different software verifiers are evaluated to check performance and soundness. We also compare our approach with a commercial tool specialized in PV systems optimization. Both results are validated with commercial design software; furthermore, some real PV systems comparison are used to show our approach effectiveness