a survey was made to study the rational given by women living in rural area of west tehran for using or not using family planning measures (1994). the purposes of this study were to investigate the reasons for using or not using family planning measures and it's relation to personal characteristics of the subjects. the samples were grouped in smaller groups: - those using effective family ...

the permian deposits in the stratigraphic section of sangsar (located in the eastern alborz), are the best expose in the semnan area. this sequence consists of the doroud (asselian-sakmarian), ruteh (artinskian-murgabian) and nessen (early djulfian) formations. the dorud formation in the studied section with 56 m thickness consists of conglomerate, sandstone and quartzite, which is disconformit...

When planning a wireless local area network, there are design issues that need to be considered. In this paper, the fundamentals of planning a wireless local area network are introduced and discussed to highlight the requirements involved. Network constraints, as encountered in the physical environment, are discussed and their relevance to wireless network design is investigated. The paper conc...

Wireless Local Area Networks (WLANs) are subjected to interference because of their working in Unlicensed Spectrum. Coverage ranges of WLANs are 30 to 300m. Channel Assignment is one of the most important problems in the WLANs. In this paper we present a Survey on the Channel Assignment techniques in IEEE 802.11.After analyzing different methods a qualitative comparison has been carried out for...

This paper evaluates the Total Vector Error of an estimated Phasor as define in IEEE C37.118 standard within different medium access in Local Area Networks (LAN). Three different LAN models (CSMA/CD, CSMA/AMP and Switched Ethernet) are evaluated. The Total Vector Error of the estimated Phasor has been evaluated for the effect of Nodes Number under the standardized network Band-width values defi...

1. The variation of threshold with field area was measured in fields homogeneous in rod-cone composition. At 15 degrees above the fovea, an increase in field diameter from 1 degrees to 5 degrees reduces the threshold sevenfold, at 25 degrees above the fovea tenfold. 2. These changes are shown to follow qualitatively from simple statistical properties of the retinal mosaic. Analytic treatment le...

Recently, low-power wireless networking standards like 802.15.1 (Bluetooth) have driven consumer interest in personal area networks (PANs). These networks are designed for inexpensively connecting low-power devices located within 1 m to 100 m of each other. In this paper, we discuss recent evolutions to the Bluetooth standard, as well as two emerging PAN standards: 802.15.4/ZigBee, and Ultra-Wi...

Cartesian routing is a fast packet routing mechanism intended for geographic addresses and can effectively accelerate the packet routing process within a local or metropolitan environment. The wide area Cartesian routing described in this paper is an extension of the Cartesian routing algorithms designed to make the exchange of internetwork packets between geographical regions possible. It also...