Bottom-up, end-user based feed, and food analysis through smartphone quantification of lateral flow assays (LFA) has the potential to cause a paradigm shift in testing capabilities. However, most ...developed devices do not test the presence of and implications of inter-phone variation. Much discussion remains regarding optimum color space for smartphone colorimetric analyses and, an in-depth comparison of color space performance is missing. Moreover, a light-shielding box is often used to avoid variations caused by background illumination while the use of such a bulky add-on may be avoidable through image background correction. Here, quantification performance of individual channels of RGB, HSV, and LAB color space and ΔRGB was determined for color and color intensity variation using pH strips, filter paper with dropped nanoparticles, and colored solutions. LAB and HSV color space channels never outperformed the best RGB channels in any test. Background correction avoided measurement variation if no direct sunlight was used and functioned more efficiently outside a light-shielding box (prediction errors < 5%/35% for color/color intensity change). The system was validated using various phones for quantification of major allergens (i.e., gluten in buffer, bovine milk in goat milk and goat cheese), and, pH in soil extracts with commercial pH strips and LFA. Inter-phone variation was significant for LFA quantification but low using pH strips (prediction errors < 10% for all six phones compared). Thus, assays based on color change hold the strongest promise for end-user adapted smartphone diagnostics.
Problematic smartphone use in adolescent students can impair their mental health and behavior, thereby affecting academic performance and interpersonal relationships as well as reducing time spent on ...physical activity. This study investigated the association between problematic smartphone use and mood, symptoms of depression, and level of physical activity in adolescent students. The sample consisted of 308 boys (46.1 percent, 16.04 ± 1.30 years) and 359 girls (53.9 percent, 15.54 ± 1.44 years), aged 13-18 years (15.77 ± 1.40 years). Four instruments were used: the Sociodemographic, School, and General Health Characteristics Questionnaire; Smartphone Addiction Scale (to measure problematic smartphone use); Brunel Mood Scale; and Beck Depression Inventory. The study found that physically inactive adolescent students were more likely to present with problematic smartphone use than those who were physically active, and girls were more likely to exhibit problematic smartphone use than boys. Adolescent students with problematic smartphone use presented with more mood disturbances and symptoms of depression than did adolescent students without problematic smartphone use. Overall, physical inactivity and problematic smartphone use can reduce vigor and increase symptoms of depression in adolescent students.
Mobile user authentication acts as the first line of defense, establishing confidence in the claimed identity of a mobile user, which it typically does as a precondition to allowing access to ...resources in a mobile device. NIST states that password schemes and/or biometrics comprise the most conventional user authentication mechanisms for mobile devices. Nevertheless, recent studies point out that nowadays password-based user authentication is imposing several limitations in terms of security and usability; thus, it is no longer considered secure and convenient for the mobile users. These limitations stress the need for the development and implementation of more secure and usable user authentication methods. Alternatively, biometric-based user authentication has gained attention as a promising solution for enhancing mobile security without sacrificing usability. This category encompasses methods that utilize human physical traits (physiological biometrics) or unconscious behaviors (behavioral biometrics). In particular, risk-based continuous user authentication, relying on behavioral biometrics, appears to have the potential to increase the reliability of authentication without sacrificing usability. In this context, we firstly present fundamentals on risk-based continuous user authentication, relying on behavioral biometrics on mobile devices. Additionally, we present an extensive overview of existing quantitative risk estimation approaches (QREA) found in the literature. We do so not only for risk-based user authentication on mobile devices, but also for other security applications such as user authentication in web/cloud services, intrusion detection systems, etc., that could be possibly adopted in risk-based continuous user authentication solutions for smartphones. The target of this study is to provide a foundation for organizing research efforts toward the design and development of proper quantitative risk estimation approaches for the development of risk-based continuous user authentication solutions for smartphones. The reviewed quantitative risk estimation approaches have been divided into the following five main categories: (i) probabilistic approaches, (ii) machine learning-based approaches, (iii) fuzzy logic models, (iv) non-graph-based models, and (v) Monte Carlo simulation models. Our main findings are summarized in the table in the end of the manuscript.
The new and groundbreaking real-time remote healthcare monitoring system on sensor-based mobile health (mHealth) authentication in telemedicine has considerably bounded and dispersed communication ...components. mHealth, an attractive part in telemedicine architecture, plays an imperative role in patient security and privacy and adapts different sensing technologies through many built-in sensors. This study aims to improve sensor-based defence and attack mechanisms to ensure patient privacy in client side when using mHealth. Thus, a multilayer taxonomy was conducted to attain the goal of this study. Within the first layer, real-time remote monitoring studies based on sensor technology for telemedicine application were reviewed and analysed to examine these technologies and provide researchers with a clear vision of security- and privacy-based sensors in the telemedicine area. An extensive search was conducted to find articles about security and privacy issues, review related applications comprehensively and establish the coherent taxonomy of these articles. ScienceDirect, IEEE Xplore and Web of Science databases were investigated for articles on mHealth in telemedicine-based sensor. A total of 3064 papers were collected from 2007 to 2017. The retrieved articles were filtered according to the security and privacy of sensor-based telemedicine applications. A total of 19 articles were selected and classified into two categories. The first category, 57.89% (
n
= 11/19), included survey on telemedicine articles and their applications. The second category, 42.1% (
n
= 8/19), included articles contributed to the three-tiered architecture of telemedicine. The collected studies improved the essential need to add another taxonomy layer and review the sensor-based smartphone authentication studies. This map matching for both taxonomies was developed for this study to investigate sensor field comprehensively and gain access to novel risks and benefits of the mHealth security in telemedicine application. The literature on sensor-based smartphones in the second layer of our taxonomy was analysed and reviewed. A total of 599 papers were collected from 2007 to 2017. In this layer, we obtained a final set of 81 articles classified into three categories. The first category of the articles 86.41% (
n
= 70/81), where sensor-based smartphones were examined by utilising orientation sensors for user authentication, was used. The second category 7.40% (
n
= 6/81) included attack articles, which were not intensively included in our literature analysis. The third category 8.64% (
n
= 7/81) included ‘other’ articles. Factors were considered to understand fully the various contextual aspects of the field in published studies. The characteristics included the motivation and challenges related to sensor-based authentication of smartphones encountered by researchers and the recommendations to strengthen this critical area of research. Finally, many studies on the sensor-based smartphone in the second layer have focused on enhancing accurate authentication because sensor-based smartphones require sensors that could authentically secure mHealth.
Optical fiber sensors are one preferred solution for temperature sensing, especially for their capability of real-time monitoring and remote detection. However, many of them still suffer from a huge ...sensing system and complicated signal demodulate process. In order to solve these problems, we propose a smartphone-based optical fiber fluorescence temperature sensor. All the components, including the laser, filter, fiber coupler, batteries, and smartphone, are integrated into a 3D-printed shell, on the side of which there is a fiber flange used for the sensing probe connection. The fluorescence signal of the rhodamine B solution encapsulated in the sensing probe can be captured by the smartphone camera and extracted into the R value and G value by a self-developed smartphone application. The temperature can be quantitatively measured by the calibrated G/R-temperature relation, which can be unified using the same linear relationship in all solid-liquid-gas environments. The performance verifications prove that the sensor can measure temperature in high accuracy, good stability and repeatability, and has a long conservation time for at least 3 months. The proposed sensor not only can measure the temperature for remote and real-time detection needs, but it is also handheld with a small size of 167 mm × 85 mm × 75 mm supporting on-site applications. It is a potential tool in the temperature sensing field.
Abstract
Objective
The objective of this study was to assess the accuracy and reliability of and time taken by a novel method using the built-in photo-edit function of smartphones compared with PACS ...in measuring hallux valgus parameters.
Methods
Seventy patients (124 ft) admitted to our hospital with a diagnosis of hallux valgus without previous surgical procedures were retrospectively reviewed. The foot radiographs of all the patients were extracted from PACS. The hallux valgus angle (HVA) and the first and second intermetatarsal angles (IMAs) were measured by PACS and by this novel method using the built-in photo-edit function of a smartphone. The results of these two methods were compared, and the accuracy and reliability were assessed between these two methods.
Results
The average parameters measured by PACS were as follows: HVA average: 37.43 ± 9.61°; IMA average: 13.37 ± 4.01°. The average parameters measured by smartphones were as follows: HVA average: 37.09 ± 9.52° and IMA average: 13.49 ± 3.91°. When compared by the independent-samples T test, the average parameters between PACS and smartphones were not significantly different (HVA PACS vs HVA smartphones:
P
= 0.776; IMA PACS vs IMA smartphones:
P
= 0.816). The variability of the HVA (F = 0.166,
P
= 0.992) and IMA (F = 0.215,
P
= 0.982) measurements was similar for the PACS and smartphones. The ICCs of the average parameters of four measurements of HVA and IMA between PACS and smartphones were 0.995 (0.991–0.997) and 0.970 (0.958–0.979), indicating that the two methods were highly correlated. For the smartphone measurement, the interobserver and intraobserver reliability was very good for HVA and IMA. The average measurement time of PACS was 25.41 ± 0.86 s, and the average measurement time of smartphones was 20.29 ± 1.22 s. The smartphone time was significantly faster than that of PACS by approximately 5 s (
P
<0.001).
Conclusion
This novel method using the built-in photo-edit function of smartphones is accurate, reliable, convenient and time-saving in measuring the angles of hallux valgus.
Heiße Quellen im Wärmebild Vollmer, Michael; Shaw, Joseph A; Nugent, Paul W ...
Physik in unserer Zeit,
09/2019, Volume:
50, Issue:
5
Journal Article
Zusammenfassung Gute Infrarotkameras werden immer günstiger, inzwischen gibt es sie auch als Smartphone‐Aufsätze. Besonders spannend wird es, wenn man damit den Yellowstone‐Park besucht. Heiße ...Thermalquellen und Geysire bieten perfekte Motive. Neben dem ästhetischen Reiz ist auch die physikalische Interpretation der Wärmebilder spannend. Wegen der relativ geringen räumlichen Auflösung von IR‐Kameras empfiehlt es sich, vom Stativ aus aufgenommene Einzelbilder zu Panoramen zusammenzusetzen. Interessant sind zudem Infrarotvideos dynamischer Vorgänge, zum Beispiel der Mischung von heißem Thermalwasser in kaltem Flusswasser.
Despite extensive research on the psychological impacts of digital technology, the nuanced dynamics between adolescent loneliness and problematic smartphone use, particularly across different ...educational levels and genders, remain underexplored. This study aims to fill this gap by employing a Random Intercept Cross-Lagged Panel Model to dissect the bidirectional relationship between loneliness and problematic smartphone use among adolescents, with a focus on the moderating roles of educational levels and gender. Engaging 3132 students from various educational institutions in China, the research conducted a three-wave longitudinal analysis across 2022–2023. The final number of participants included 1120 adolescents (53.5% female; age in 2022: M = 14.57 years, SD = 1.57). Results reveal that loneliness significantly predicts problematic smartphone use, but not vice versa, highlighting a unidirectional influence. The study uncovers crucial differences across educational levels and gender, emphasizing the stronger effect of loneliness on problematic smartphone use among junior high students and female adolescents. These findings underscore the complexity of adolescent loneliness and its relationship with digital behavior, suggesting a need for tailored interventions considering both gender and developmental stages.
The foot is a vital organ, as it stabilizes the impact forces between the human skeletal system and the ground. Hence, precise foot dimensions are essential not only for custom footwear design, but ...also for the clinical treatment of foot health. Most existing research on measuring foot dimensions depends on a heavy setup environment, which is costly and ineffective for daily use. In addition, there are several smartphone applications online, but they are not suitable for measuring the exact foot shape for custom footwear, both in clinical practice and public use. In this study, we designed and implemented computer-vision-based smartphone application
that provides the functionality to automatically measure the four essential dimensions (length, width, arch height, and instep girth) of a human foot from images and 3D scans. We present an instep girth measurement algorithm, and we used a pixel per metric algorithm for measurement; these algorithms were accordingly integrated with the application. Afterwards, we evaluated our application using 19 medical-grade silicon foot models (12 males and 7 females) from different age groups. Our experimental evaluation shows that
could measure the length, width, arch height, and instep girth with an accuracy of 95.23%, 96.54%, 89.14%, and 99.52%, respectively. A two-tailed paired
-test was conducted, and only the instep girth dimension showed a significant discrepancy between the manual measurement (MM) and the application-based measurement (AM). We developed a linear regression model to adjust the error. Further, we performed comparative analysis demonstrating that there were no significant errors between MM and AM, and the application offers satisfactory performance as a foot-measuring application. Unlike other applications, the iOS application we developed,
, fulfils the requirements to automatically measure the exact foot dimensions for individually fitted footwear. Therefore, the application can facilitate proper foot measurement and enhance awareness to prevent foot-related problems caused by inappropriate footwear.
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