713 research outputs found
Can I Borrow Your ATM? Using Virtual Reality for (Simulated) In Situ Authentication Research
In situ evaluations of novel authentication systems, where the system is evaluated in its intended usage context, are often infeasible due to ethical and legal constraints. Consequently, researchers evaluate their authentication systems in the lab, which questions the eco-logical validity. In this work, we explore how VR can overcome the shortcomings of authentication studies conducted in the lab and contribute towards more realistic authentication research. We built a highly realistic automated teller machine (ATM) and a VR replica to investigate through a user study (N=20) the impact of in situ evaluations on an authentication system‘s usability results. We evaluated and compared: Lab studies in the real world, lab studies in VR, in situ studies in the real world, and in situ studies in VR. Our findings highlight 1) VR‘s great potential to circumvent potential restrictions researchers experience when evaluating authentication schemes and 2) the impact of the context on an authentication system‘s usability evaluation results. In situ ATM authentications took longer (+24.71% in the real world, +14.17% in VR) than authentications in a traditional (VR) lab environment and elicited a higher sense of being part of an ATM authentication scenario compared to a real-world and VR-based evaluation in the lab. Our quantitative findings, along with participants‘ qualitative feedback, provide first evidence of increased authentication realism when using VR for in situ authentication research. We provide researchers with a novel research approach to conduct (simulated) in situ authentication re-search, discuss our findings in the light of prior works, and conclude with three key lessons to support researchers in deciding when to use VR for in situ authentication research
RepliCueAuth: Validating the Use of a lab-based Virtual Reality Setup for Evaluating Authentication System
Evaluating novel authentication systems is often costly and time-consuming. In this work, we assess the suitability of using Virtual Reality (VR) to evaluate the usability and security of real-world authentication systems. To this end, we conducted a replication study and built a virtual replica of CueAuth [52], a recently introduced authentication scheme, and report on results from: (1) a lab-based in-VR usability study (N=20) evaluating user performance; (2) an online security study (N=22) evaluating system’s observation resistance through virtual avatars; and (3) a comparison between our results and those previously reported in the real-world evaluation. Our analysis indicates that VR can serve as a suitable test-bed for human-centred evaluations of real-world authentication schemes, but the used VR technology can have an impact on the evaluation. Our work is a first step towards augmenting the design and evaluation spectrum of authentication systems and offers ground work for more research to follow
Health education and the control of urogenital schistosomiasis: assessing the impact of the Juma na Kichocho comic-strip medical booklet in Zanzibar
Endeavours to control urogenital schistosomiasis on Unguja Island (Zanzibar) have focused on school-aged children. To assess the impact of an associated health education campaign, the supervised use of the comic-strip medical booklet Juma na Kichocho by Class V pupils attending eighteen primary schools was investigated. A validated knowledge and attitudes questionnaire was completed at baseline and repeated one year later following the regular use of the booklet during the calendar year. A scoring system (ranging from 0.0 to 5.0) measured children's understandings of schistosomiasis and malaria, with the latter being a neutral comparator against specific changes for schistosomiasis. In 2006, the average score from 751 children (328 boys and 423 girls) was 2.39 for schistosomiasis and 3.03 for malaria. One year later, the score was 2.43 for schistosomiasis and 2.70 for malaria from 779 children (351 boys and 428 girls). As might be expected, knowledge and attitudes scores for schistosomiasis increased (+0.05), but not as much as originally hoped, while the score for malaria decreased (-0.33). According to a Kolmogorov-Smirnov test, neither change was statistically significant. Analysis also revealed that 75% of school children misunderstood the importance of reinfection after treatment with praziquantel. These results are disappointing. They demonstrate that it is mistaken to assume that knowledge conveyed in child-friendly booklets will necessarily be interpreted, and acted upon, in the way intended. If long-term sustained behavioural change is to be achieved, health education materials need to engage more closely with local understandings and responses to urogenital schistosomiasis. This, in turn, needs to be part of the development of a more holistic, biosocial approach to the control of schistosomiasis
Antibodies against Merozoite Surface Protein 1 and 2 in Sudanese children
Background: Malaria is a serious childhood disease causing high morbidity and mortality despite control measures. Immunological control against malaria was initiated early, and immunity acquired by children in endemic areas, which is age and exposure dependant, differs in different endemic settings. The objective of the study was to determine antibodies against Merozoite surface protein-1 (MSP-I) and Merozoite surface protein-2 (MSP-2), and to determine their relation to the age of Sudanese children. Methodology: The study was descriptive, cross-sectional, conducted in Khartoum Children Emergency Hospital (KCEH). 150 children with positive blood films for P. falciparum malaria were classified according to age, and a blood sample was taken from each one, and tested for antibodies against MSP-I and MSP-2. Results: Antibodies to MSP-I and MSP-2 were 46% and 42% respectively. Sero-positivity and sero-negativity for both antigens were 26.6% and 42.7% respectively. Seropositivity to either MSP2 or MSP1antigen alone was present in 18.7% and 12% of patients respectively. High seropositivity (52.9%) was found in the age group 12-15 years of age. Conclusion: MSP-1 and MSP-2 antibodies in Sudanese children according to this study were age dependant, and findings were similar to what had been reported in some African countries.Key words: P. falciparum malaria, MSP-I, MSP-2
Frequency of consumption and nutrient composition of composite dishes commonly consumed in the UK by South Asian Muslims originating from Bangladesh, Pakistan and East Africa (Ismailis)
Introduction: This paper presents information on the nutrient composition of commonly consumed traditional dishes eaten by the three major South Asian Muslim groups residing in Britain, namely Bangladeshi, Pakistani and East African Ismaili Muslims.
Methods: Information regarding the most common dishes consumed by South Asian Muslims originating from Bangladesh, Pakistan and East Africa (Ismailis) and living in London was obtained from 7-day menu records over two seasons. For each common dish, weighed recipes were collected in triplicate and the composition (energy and selected nutrients) was calculated from the ingredients and cooked weight of the dish.
Results: The three Muslim groups showed considerable variation in traditional foods commonly consumed as well as variation in fat and energy contents of similar recipes both within and between groups. Nutrient composition of commonly consumed dishes is presented calculated from the recipe nearest the average in terms of fat and energy for a particular dish.
Discussion and Conclusions: The potential uses of the data, one of which would be to improve dietary compliance (especially to lower fat intakes) amongst the three diverse South Asian Muslim groups, are discussed
Virtual Reality Observations: Using Virtual Reality to Augment Lab-Based Shoulder Surfing Research
Given the difficulties of studying the shoulder surfing resistance of authentication systems in a live setting, researchers often ask study participants to shoulder surf authentications by watching two-dimensional (2D) video recordings of a user authenticating. How-ever, these video recordings do not provide participants with a realistic shoulder surfing experience, creating uncertainty in the value and validity of lab-based shoulder surfing experiments. In this work, we exploit the unique characteristics of virtual reality (VR) and study the use of non-immersive/immersive VR recordings for shoulder surfing research. We conducted a user study (N=18) to explore the strengths and weaknesses of such a VR-based shoulder surfing research approach. Our results suggest that immersive VR observations result in a more realistic shoulder surfing experience, in a significantly higher sense of being part of the authentication environment, in a greater feeling of spatial presence, and in a higher level of involvement than 2D video observations without impacting participants’ observation performance. This suggests that studying shoulder surfing in VR is advantageous in many ways compared to currently used approaches, e.g., participants can freely choose their observation angle rather than being limited to a fixed observation angle as done in current methods. We discuss the strengths and weaknesses of using VR for shoulder surfing research and conclude with four recommendations to help researchers decide when (and when not) to employ VR for shoulder surfing research in the authentication research domain
Investigating Rain Attenuation Models for Satellite Links in Tropical Nigeria
The analyses of rain models for satellite communication links of Ku and Ka bands in Lagos, Nigeria is the focus of this paper. The choice of these frequency bands was informed by the acknowledged fact that satellite signal fading and outages are predominant at those bands. The ITU-R P. 618-12 is the globally adopted prediction model; temperate, equatorial and tropical regions, inclusive. However, there was need to review the suitability of this model especially as it concerned equatorial and tropical stations. Rainfall data spanning a period of three years were collected from Nigerian Meteorological Agency (NIMET). The ITU-R P. 618-12 model along with some renowned prediction models were analyzed and their performances with the locally recorded measurement data were compared to establish their suitability or otherwise. The results obtained suggested ITU-R P. 618-12 exhibited the overall best performance at 12 GHz while DAH showed best performance at 26 GHz, even as both models underestimated and overestimated the measurement at Ku and Ka bands respectively. Again, at both frequencies, SST presented the worst performances
Patterns of acute hospital and specialist palliative care use among people with non-curative upper gastrointestinal cancer
Purpose: Upper gastrointestinal (GI) cancers contribute to 16.7% of UK cancer deaths. These patients make high use of acute hospital services, but detail about palliative care use is lacking. We aimed to determine the patterns of use of acute hospital and hospital specialist palliative care services in patients with advanced non-curative upper GI cancer. Methods: We conducted a service evaluation of hospital use and palliative care for all patients with non-curative upper GI cancer seen in one large hospital, using routinely collected data (2019–2022). We report and characterise hospital admissions and palliative care within the study time period, using descriptive statistics, and multivariable Poisson regression to estimate the unadjusted and adjusted incidence rate ratio of hospital admissions. Results: The total with non-curative upper GI cancer was 960. 86.7% had at least one hospital admission, with 1239 admissions in total. Patients had a higher risk of admission to hospital if: aged ≤ 65 (IRR for 66–75 years 0.71, IRR 76–85 years 0.68; IRR > 85 years 0.53; p < 0.05), or lived in an area of lower socioeconomic status (IMD Deciles 1–5) (IRR 0.90; p < 0.05). Over the 4-year period, the rate of re-admission was higher in patients not referred to palliative care (rate 0.52 readmissions/patient versus rate 1.47 readmissions/patient). Conclusion: People with advanced non-curative gastrointestinal cancer have frequent hospital admissions, especially if younger or from areas of lower socioeconomic status. There is clear association between specialist palliative care referral and reduced risk of hospitalisation. This evidence supports referral to specialist palliative care
通電による異常増殖した藻類の除去
This study investigated a method of removing algae by energizing a metal electrode plate set in water containing abnormally proliferated algae. As algae have negative charge in water, they migrated to the anode by electrophoresis in an electric field. Combining with cations eluting from the anode, especially aluminum ions, the algae formed cohesive floc and then adhered on the anode surface without returning into the water. In the continuous flow apparatus, algae were removed at high removal rate by taking out the algae adhered on anode regularly. It was shown that the electrochemical method can efficiently remove algae from water
Assessment of the Off-season Rainfall of January to February 2020 and Its Socio Economic Implications in Tanzania: A Case Study of the Northern Coast of Tanzania
This article examines the off season rainfall in northern coast Tanzania (NCT) including Zanzibar which occurred in January and February 2020 (JF). Like the JF rainfalls of 2001, 2004, 2010, 2016 and 2018, the JF (2020) rainfall was more unique in damages including loss of lives, properties and infrastructures. The study used the NCEP/NCAR reanalysis data to examine the cause of uniqueness of JF rainfall in 2001, 2004, 2010, 2016, 2018 and 2020 over NCT and Zanzibar. These datasets include monthly mean u, v wind at 850, 700, 500, and 200 mb; SSTs, mean sea level pressure (MSLP) anomalies, Dipole Mode Index (DMI), and monthly rainfall from NCT and Zanzibar stations. Datasets were processed and calculated into long term, seasonal, and monthly averages, indeed, Precipitation Index (PI) was calculated. Correlation analysis between the rainfall (December to January), SST, DMI and 850 mb wind vectors; and long-term percentage contribution of investigated parameters was calculated. Results revealed significant positive and negative correlations between JF rainfall, SSTs and DMI. Moreover, JFs of 2004 and 2016 had higher rainfalls of 443 mm with percentage contribution of up to 406%, while January and February, 2020 had the highest of 269.1 and 101.1mm in Zanzibar and 295 and 146.1 mm over and NCT areas, with highest January long-term rainfall contribution of 356% in Zanzibar and 526% over NCT. The DJF (2019/20) had the highest rainfall record of 649.5 mm in Zanzibar contributing up to 286%, while JF 2000 rainfall had a good spatial and temporal distribution over most NCT areas. JF, 2020 rainfall had impacts of more than 20 people died in Lindi and several infrastructures including Kiyegeya Bridge in Morogoro were damaged. Conclusively, more research works on understanding the dynamics of wet and dry JF seasons should be conducted
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