The use of modified predicate transition nets for the modeling of computer communication protocols is investigated in this paper. The lower three layers of the OS! architecture are of primary concern. On the Network Layer (Layer 3), fragmentation and reassembly, routing, store and forward buffering and congestion control mechanisms are treared. The Data-Link Layer (Layer 2) leads to window-flow...

abstract creating suitable classrooms that can meet the educational needs of mentally-retarded students is vitally important. the present study explores the effect of three physical characteristics of classroom environment on the creativity of educable mentally-retarded children: window view, window size, and classroom size. the participants, one hundred 9-to-11-year-old girl students, took the...

This paper studies TCP performance over static, ad hoc networks that use IEEE 802.11 protocol as the access method. Our study reveals some interesting results. First, there exists an optimal value for TCP congestion window size, at which the TCP throughput is maximized. However, TCP does not operate around this optimal point, and typically grows its window much larger; this leads to decreased t...

Growing interest in Fe2O3 as a light harvesting layer in solar energy conversion devices stems from its unique combination of stability, nontoxicity, and exceptionally low material cost. Unfortunately, the known methods for conformally coating high aspect ratio structures with Fe2O3 leave a glaring gap in the technologically relevant temperature range of 170-350 C. Here, we elucidate a self-lim...

introduction: poor sensitivity and poor signal to noise ratio because of low injected thallium dose and presence of scattered photons are the main problems in using thallium in scintigraphic imaging of the heart. scattered photons are the main cause of degrading the contrast and resolution in spect imaging that result in error in quantification. thallium decay is very complicated and photons ar...

Cu nano-particles (Cu-NPs) were embedded into the SiO2 layer of a Cu/SiO2/Pt structure to examine their influence on resistive switching characteristics. The device showed a reversible resistive switching behavior, which was due to the formation and rupture of a Cu-conducting filament with an electrochemical reaction. The Cu-NPs enhanced the local electric field within the SiO2 layer, which cau...

Micromachined, micron-thick porous alumina membranes with closed pore endings show high electron transparency above an energy of 5 keV. This is due to the channeling of electrons along the negatively charged insulating pores after surmounting the thin entrance layer. We also find a sharp hightransparency energy window at energies as low as 2 keV which may be the result of a local maximum of cha...

A mathematical model for the specification and verification of a data link layer protocol is proposed. The weakest precondition calculus, developed by Dijkstra, originally for sequential programs, has been chosen for this purpose. It is demonstrated that the wp–calculus provides a basis, not only for the modeling but also, for a straightforward and thorough analysis of large and complex distrib...

This study used DNN (Deep Neural Network) to process Voice Activation Detection, and discussed the following variable which affect the performance of VAD: (1) The analyzed window size of MFCC feature extraction, (2) Layer number of DNN, (3) Signal to Noise Ratio, and (4) The type of background condition. This experiment used NTPU Noise Corpus, which is mixed by many kinds of background noise re...

Recent advances in cognitive radio technology have drawn immense attention to higher layer protocols above medium access control, such as transmission control protocol (TCP). Most proposals to improve the TCP performance in cognitive radio (CR) networks have assumed that either all nodes are in CR networks or the TCP sender side is in CR links. In those proposals, lower layer information such a...