Many scholars have argued that deliberate birth spacing may have played a role before and during the modern fertility transition. There are good historical and theoretical reasons for this view, but it has proved to be hard to demonstrate convincingly that birth intervals were in fact partly determined by attempts at deliberate fertility control. This paper suggests a method of securing evidenc...

We propose a mean-field method to calculate approximately the spacing distribution functions p((n))(s) in one-dimensional classical many-particle systems. We compare our method with two other commonly used methods, the independent interval approximation and the extended Wigner surmise. In our mean-field approach, p((n))(s) is calculated from a set of Langevin equations, which are decoupled by u...

OBJECTIVES This paper examines the effect of household crowding on inter-pregnancy spacing and its association with socioeconomic indicators, among parous mothers delivered in an urban environment. DESIGN Cross sectional survey. METHODS Sociodemographic data were obtained on 2466 parous women delivering at eight hospitals in Greater Beirut over a one year period. Statistical methodology com...

In this paper we propose a new two level traffic parameter estimation approach based on traffic classification into three classes: free flow, congested and stopped traffic in image time series of airborne optical remote sensing data. The proposed method is based on the combination of various techniques: change detection in two images, image processing such as binarization and filtering and inco...

Intelligent vehicle platoon driving is a process of flexible control based on the coordination between vehicle and highway in intelligent vehicle-highway system. It can improve the velocities and reduce the spacing between vehicles in the platoon, thus, to improve road capacity and road safety. It is the most important for developing intelligent vehicle-highway system to construct intelligent v...

To analyze the influence of distance between tunnels at bridge-tunnel junction in mountainous area on driving safety under crosswind, a vehicle dynamics model is established by Carsim software. Under conditions different speeds (60km/h, 80km/h and 100km/h), wind scales (level 6–9) three alignment combinations (tunnel-straight road-tunnel, tunnel-curving tunnel-the combination straight curves ro...