this study aimed to develop an index that can rank welding workplace that associate well with possible health risk of welders.welding fumes health index (wfhi) were developed based on data from case studies conducted in plant 1 and plant 2. personal sampling of welding fumes to assess the concentration of metal constituents along with series of lung function tests was conducted. fifteen metal c...

When sensor nodes are organized in clusters, they could use either single hop or multi-hop mode of communication to send their data to their respective cluster heads. We present a systematic cost-based analysis of both the modes, and provide results that could serve as guidelines to decide which mode should be used for given settings. We determine closed form expressions for the required number...

Node clustering and data aggregation are popular techniques to reduce energy consumption in large WSNs and a large body of literature has emerged describing various clustering protocols. Unfortunately, for practitioners wishing to exploit clustering in deployments, there is little help when trying to identify a protocol that meets their needs. This paper takes a step back from specific protocol...

in the present study, an application of multilevel modeling approach to the input- output analysis are presented first, the regional input-output table of all provinces in iran was extracted based on the adjusted flegg location quotient method (aflq). second differentiation in the leontief technical coefficients and the backward and forward linkages among various activities and sectors of all p...

A wireless sensor network has a wide application domain which is expanding everyday and they have been deployed pertaining to their application area. An application independent approach is yet to come to terms with the ongoing exploitation of the WSNs. In this paper we propose a decentralized lifetime maximizing tree for application independent data aggregation scheme using the clustering for d...

Recently, underwater wireless sensor network is one of the popular research topics to scientist. There are many novel methodologies to reach the goal of the effectiveness network performance such as cluster-based structure, in-network data aggregation, etc. In this paper, we assume the network is clustered by a specific clustering scheme. Then, we suggest a new geographicaldata-aggregation meth...

the prime objective of deploying largescale wireless sensor networks is to collect information from to control systems associated with these networks. Wireless sensor networks are widely used in application domains such as security and inspection, environmental monitoring, warfare, and other situations especially where immediate responses are required such as disasters and medical emergency. Wh...

In wireless sensor networks with dynamic clustering, the cluster heads are usually not selected on the basis of their locations. This causes irregular distribution of cluster heads and highly variable number of nodes in the clusters. Also, some of the clusters are spread over large areas within the network, causing limited spatial correlation between associated sensor nodes.These irregularities...

Energy efficiency is the most important issue in all facets of wireless sensor networks (WSNs) operations because of the limited and non-replenish able energy supply. Data aggregation mechanism is one of the possible solutions to prolong the life time of sensor nodes and on the other hand it also helps in eliminating the data redundancy and improving the accuracy of information gathering, is es...