This research is aimed to establish the small wireless sensor network under the real environment. The objectives this research is aimed to study the data transmission and evaluate the data transmission performance of RPL protocol in wireless sensor network. Four nodes of wireless sensor network have been installation and transmissions between nodes in single-hop and multi-hop have been simulation for testing and analyzing data from the network following the transmission performance index. The research found that the number of hop and building environment are the principle factor to the performance of RPL protocol this might be the major limit to implement the RPL protocol in wireless sensor network

This thesis proposes technical performance evaluation and economic decence for the combination of harmonic correction devices in Industry. Currently an electronic device is popularly applied in power network. Although it is a higher performance device than the existing device it still causes the power quality issues and then network failure. Especially harmonic disturbance in the network it is a harmonic source that generates harmonic current into the network. Many types and solutions are available in the present time therefore the suitable and optimal financial solution must be considered. A network model for the analysis of harmonic correction devices suitable solutions and optimal financial has been established in the simulation software that bases on the power and Break Even Point (BEP) equations. The results of analysis shown that the performance of harmonic correction devices suitable solution and BEP of investment in match to the using of a detuned filter bank and an active harmonic filter (case 8) thus these information will be valued for the end-user.

We present the comparison of CDMA MAC protocol with and without beat noise by using 2-D optical CDMA MAC protocol over WDM networks. We use the asymmetric primehop sequence code. Moreover we analyse the effect of the number of available wavelengths in tenns ofaverage number of attempted to transmissions per time slot (offered load) and beat noise is considered. The presented numerical results based on the throughput and delay time versus the offered load. We divide into two parts. The first one we consider the effect of the number of available wavelengths. Another is the effect of with and without beat noise in the 2-D OCDMA over WDM systems.

We present the comparison of CDMA MAC protocol with and without beat noise by using 2-D optical CDMA MAC protocol over WDM networks. We use the asymmetric primehop sequence code. Moreover we analyse the effect of the number of available wavelengths in tenns ofaverage number of attempted to transmissions per time slot (offered load) and beat noise is considered. The presented numerical results based on the throughput and delay time versus the offered load. We divide into two parts. The first one we consider the effect of the number of available wavelengths. Another is the effect of with and without beat noise in the 2-D OCDMA over WDM systems.

Currently the internet services with 3G technology by mobile phone operators in Thailand are different in the performance. The mobile phone operators have already launched 3G technology with 2G frequency ranges which are limited in the efficiency. This paper aims to compare the efficiency of the internet service with 3G technology by three mobile phone operators (AIS DTAC and Truemove H) in Thailand. There are three type of testing as follows: Ping to both domestic and international website Bandwidth speed test and FTP Test (upload and download) are used to evaluate the performance of these mobile phone operators. There were five places in Bangkok where are the top of the network congestion list for such testing the three mobile phone operators. The result showed that AIS gives the best performance in the ping test. Truemove H introduces the best performance in both FTP and Bandwidth speed test. The DTAC performances are moderated level for every tests.