Impact of Obstacles on the Degree of Mobile Ad Hoc Connection Graphs

What is the impact of obstacles on the graphs of connections between stations in Mobile Ad hoc Networks? In order to answer, at least partially, this question, the first step is to define both an environment with obstacles and a mobility model for the stations in such an environment. The present paper focuses on a new way of considering the mobility within environments with obstacles, while keeping the core ideas of the well-known Random WayPoint mobility model (a.k.a RWP). Based on a mesh-partitioning of the space, we propose a new model called RSP-O-G for which we compute the spatial distribution of stations and analyse how the presence of obstacles impacts this distribution compared to the distribution when no obstacles are present. Coupled with a simple model of radio propagation, and according to the density of stations in the environment, we study the mean degree of the connection graphs corresponding to such mobile ad hoc networks

Les facteurs explicatifs de l'épargne des actifs et des retraités des secteurs privé et public

This paper uses the data from INSEE’s 2004 household assets survey (Enquête Patrimoine) to highlight the determinants of holding a contractual financial saving plan to provide supplementary income, distinguishing between working and retired households. Our results suggest that the profiles of individuals holding certain types of contractual saving plans (retirement saving and life insurance) are determined by factors common to workers and retirees, and tend to confirm behaviour of saving for retirement. Factoring in occupational status reveals specific profiles that suggest that private-sector workers are disadvantaged, particularly with regard to retirement saving. The discrepancy between the public and the private sector in terms of the supplementary retirement saving plans available is a potential source of inequality in terms of household participation in these schemes. The overlap between holding retirement savings and holding alternative savings (life insurance, employee saving plans) in preparation for old age indicates that altruism and a wish to make inter-generational transfers are among the motivations of holders of annuity products, since a significant proportion hold supplementary death insurance. The need to save for retirement via a non-occupational plan is lessened by the availability of a company retirement saving plan, which households with high incomes and financial assets are the most likely to hold. Employee saving plans, which are the only type of saving plan open to younger cohorts of households, are complementary to company retirement saving plans

Health Information Literacy: An Assessment of Commercial Bus Drivers’ Patronage of ‘Mama Put’ Food Outlet, and Their Sense of Vulnerability to Food Poison

Health information can be an effective means of guiding consumers to healthy eating as well as make them aware of certain diseases that can be contacted as a result of unhygienic environment where food is prepared or sold. Despite hygienic environment, little is known about the actual impact of health information literacy on commercial bus drivers about “mama put” food outlets. The work was an empirical study and survey research design was adopted. The work was anchored on Consumer Pull Model. Data were collected in Onitsha, Anambra State, Nigeria among commercial bus drivers by administering questionnaire to a sample of 352 respondents at Upper Iweka Motor Park, Onitsha. This study found that commercial bus drivers in Onitsha are not health information literate and not aware that patronizing “mama put” food outlets make them vulnerable to food poison. It also established that price of a plate of food and quantities are two major factors that influence commercial bus drivers to patronize mama put food outlets. Based on these findings, this study recommended that health regulatory bodies should educate both the “mama put” food vendors and the commercial bus drivers on the importance of hygienic environment where food is prepared or sold. Keywords: Health information literacy, “Mama Put”, Commercial bus drivers, hygienic environment, Food poison. DOI: 10.7176/JPID/50-08 Publication date:June 30th 2019

Low Speed Bearing Condition Monitoring – A Case Study

The heath condition of worm-wheel gearbox is critical for the reliable and continuous operation of passenger escalators. The vibration sensor has been widely installed in the gearbox and the vibration level is usually utilized as a health indicator. However, vibration level is not robust in slow speed bearing condition monitoring. In this paper, the health condition of two slow speed bearings was evaluated using vibration data collected from sensors installed in the shaft. It has been shown that the vibration level fails to indicator the bearing health condition. The assessment accuracy can be improved by combining several simple methods