Hybrid game approach‐based channel congestion control for the Internet of Vehicles

Communications between the Internet of Vehicles in smart cities helps increase the awareness and safety among drivers. However, the channel congestion problem is considered as a key challenge for the communication networks due to continuing collection and exchange of traffic information in dense environments. The channel congestion problem degrades the efficiency and reliability of the ad hoc network. Therefore, the adaptation of the data rate and power control is considered as one of the effective solutions to mitigate channel congestion. This paper develops a new hybrid game transmission rate and power channel congestion control approach on the Internet of Vehicle networks where the nodes play as greedy opponents demanding high information rates with the maximum power level. Furthermore, the existence of a Nash equilibrium, which is the optimal information rate and power transmission for every vehicle, is established. Simulation results demonstrate that the proposed approach enhances the network performance by an overall percentage of 42.27%, 43.94% and 47.66% regarding of channel busy time, messages loss and data collision as compared to others. This increases the awareness and performance of the vehicular communication network

Effectiveness of smart phone application use as continuing medical education method in pediatric oral health care: a randomized trial

Background Continuing education aims at assisting physicians to maintain competency and expose them to emerging issues in their field. Over the last decade, approaches to the delivery of educational content have changed dramatically as medical education at all levels is now benefitting from the use of web-based content and applications for mobile devices. The aim of the present study is to investigate through a randomized trial the effectiveness of a smart phone application to increase public health service physicians’ (PHS physicians) knowledge regarding pediatric oral health care. Method Five of all seven DHCs (District Health Center) in Tehran, which were under the supervision of Tehran University of Medical Sciences and Iran University of Medical Sciences, were selected for our study. Physicians of one DHC had participated in a pilot study. All PHS physicians in the other four centers were invited to the current study on a voluntary basis (n = 107). They completed a self-administered questionnaire regarding their knowledge, attitudes, practice in pediatric dentistry, and background. PHS physicians were assigned randomly to intervention and control groups; those in the intervention group, received a newly designed evidence-based smartphone application, and those in the control group received a booklet, a CME seminar, and a pamphlet. A post-intervention survey was administered 4 months later and t-test and repeated measures ANCOVA (Analysis of Covariance) were performed to measure the difference in the PHS physicians’ knowledge, attitude and practice. Results In both groups, the mean knowledge scores were significantly higher (p-Value < 0.001) in post-intervention data compared to those at baseline. Similar results existed in attitude and practice scores. Although the scores in knowledge in the intervention group indicating potentially greater improvement when compared to those of the control group, the differences between the two groups were not statistically significant (dif: 0.84, 95% CI − 0.35 to 2.02). Conclusion In the light of the limitations of the present study, smart phone applications could improve knowledge, attitude and practice in physicians although this method was not superior to the conventional method of CME

Psychosocial determinants of dental service utilization among adults: Results from a population-based survey (Urban HEART-2) in Tehran, Iran

Objectives: To evaluate the association between dental service utilization and mental health in an adult population in the context of the socioeconomic status of the participants. Subjects and Methods: Multi-stage cluster random sampling was performed in Tehran, Iran, in 2011. Data were collected on dental service utilization, barriers of dental visit, self-perceived oral health, mental health, age, gender, education, and wealth status. The complex sample analysis method in SPSS and the survey data analysis menu in STATA were employed for statistical evaluation. Results: Of 20,320 participants, 25-36 suffered from disorders in at least one of the domains of somatization, anxiety, social dysfunction, and depression. Only 56 of the participants visited a dentist at least once during the last year. The main barriers to a dental visit were "no perceived need" and "high costs." Females, the richest participants, subjects aged 25-64-year-old, and those with poor self-perceived oral health, mental health disorders, and higher education had more visits. The participants who perceived the need but did not visit a dentist due to some reasons mostly comprised females, those aged 25-44-year-old, those with a poor perceived oral health, disordered people in all domains of mental health, and poorer participants. Conclusion: Dental service utilization was influenced by socioeconomic factors and the mental health status of the adult population after controlling for multiple confounders. Reducing financial hardship and providing health education on the importance of preventive visits may decrease barriers to regular visits in countries with developing oral health systems. © 2015 European Journal of Dentistry

Hybrid power control and contention window adaptation for channel congestion problem in internet of vehicles network

Technology such as vehicular ad hoc networks can be used to enhance the convenience and safety of passenger and drivers. The vehicular ad hoc networks safety applications suffer from performance degradation due to channel congestion in high-density situations. In order to improve vehicular ad hoc networks reliability, performance, and safety, wireless channel congestion should be examined. Features of vehicular networks such as high transmission frequency, fast topology change, high mobility, high disconnection make the congestion control is a challenging task. In this paper, a new congestion control approach is proposed based on the concept of hybrid power control and contention window to ensure a reliable and safe communications architecture within the internet of vehicles network. The proposed approach performance is investigated using an urban scenario. Simulation results show that the network performance has been enhanced by using the hybrid developed strategy in terms of received messages, delay time, messages loss, data collision and congestion ratio

Non-cooperative game based congestion control for data rate optimization in vehicular ad hoc networks

The growth of connected vehicles in smart cities increases the number of information being communicated on the Internet of Vehicle networks. This causes wireless channel congestion problems, which degrades the network performance and reliability due to the low throughput, high average delay and the high packets loss. Therefore, this paper proposes a non-cooperative game approach to control congestion in the vehicular ad-hoc network channel where the nodes behave as selfish players requesting high data transmission rates. Moreover, the satisfaction of the Nash equilibrium condition for the optimum data transmission rate for each vehicle, is proven. A utility function is introduced based on data transmission rates, the priority of vehicles and contention delay in order to obtain the optimal rates. The performance of the proposed approach has been evaluated and validated in comparison with three others approaches over two testing scenarios for highway and urban traffic. The results show that the network performance and efficiency have been improved by an overall average of 35%, 30% and 37.17% in terms of packets loss, channel busy time and number of collision messages, respectively, as compared with the state-of-the-art-strategies for the highway testing scenario. Similar performance is achieved for the urban testing scenario. Keywords: Vehicular ad hoc networks, Congestion control, Non-cooperative game approach, Data rate adaptation, IoV applications

Tooth brushing, tongue cleaning and snacking behaviour of dental technology and therapist students

Objective: To determine the tooth brushing, tongue cleaning and snacking behaviour of dental technology and therapist students. Methods: A descriptive cross-sectional study of students of Federal School of Dental Therapy and Technology Enugu, Nigeria. Self-administered questionnaire was used to obtain information on demography, frequency, duration and technique of tooth brushing and tongue cleaning as well as information on consumption of snacks. Results: A total of 242 students responded. Dental technology students made up 52.5% of the respondents and dental therapist in training made up 47.5%. Majority (63.2%) of the respondents considered the strength of tooth brush when purchasing a tooth brush and 78.9% use tooth brushes with medium strength. Seven-tenth (71.9%) of the respondents brush their teeth twice daily and 52.1% brush for 3&#x2013;5 minutes. About one-third (30.2%) brush their teeth in front of a mirror. Chewing stick was used by 51.7% of respondents in addition to the use of tooth brush. Tongue cleaning was done by 94.2% with only 9.5% using a tongue cleaner. Only 20.2% reported regular snacks consumption. Nine-tenth (90.4%) of respondents were previously involved in educating others, apart from their colleagues, on tooth brushing. Conclusion: This survey revealed that most of the dental therapy and technology students had satisfactory tooth-brushing behaviour. The zeal to educate others about proper tooth brushing revealed in this study suggests that the students may be helpful in oral health promotion

Waterpipe smoking among health sciences university students in Iran: perceptions, practices and patterns of use

<p>Abstract</p> <p>Background</p> <p>In recent years waterpipe smoking has become a popular practice amongst young adults in eastern Mediterranean countries, including Iran. The aim of this study was to assess waterpipe smoking perceptions and practices among first-year health sciences university students in Iran and to identify factors associated with the initiation and maintenance of waterpipe use in this population.</p> <p>Results</p> <p>Out of 371 first-year health sciences students surveyed, 358 eight students completed a self-administered questionnaire in the classrooms describing their use and perceptions towards waterpipe smoking. Two hundred and ninety six responders met study inclusion criteria. Waterpipe smoking was common among first-year health sciences university students, with 51% of students indicating they were current waterpipe smokers. Women were smoking waterpipes almost as frequently as men (48% versus 52%, respectively). The majority of waterpipe smokers (75.5%) indicated that the fun and social aspect of waterpipe use was the main motivating factor for them to continue smoking. Of waterpipe smokers, 55.3% were occasional smokers, using waterpipes once a month or less, while 44.7% were frequent smokers, using waterpipes more than once a month. A large number of frequent waterpipe smokers perceived that waterpipe smoking was a healthier way to use tobacco (40.6%) while only 20.6% thought it was addictive. Compared to occasional smokers, significantly more frequent smokers reported waterpipe smoking was relaxing (62.5% vs. 26.2%, <it>p </it>= 0.002), energizing (48.5% vs. 11.4%, <it>p </it>= 0.001), a part of their culture (58.8% vs. 34.1%, <it>p </it>= 0.04), and the healthiest way to use tobacco (40.6% vs. 11.1%, <it>p </it>= 0.005).</p> <p>Conclusions</p> <p>Social and recreational use of waterpipes is widespread among first-year health sciences university students in Iran. Women and men were almost equally likely to be current waterpipe users. Public health initiatives to combat the increasing use of waterpipes among university students in Iran must consider the equal gender distribution and its perception by many waterpipe smokers as being a healthier and non-addictive way to use tobacco.</p