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Modeling the Processes of Packet Losses in Telecommunication Networks in Program Anylogic
Issue:
Volume 2, Issue 1, June 2018
Pages:
1-5
Received:
6 March 2018
Accepted:
27 March 2018
Published:
20 April 2018
Abstract: This paper deals with assessing and comparisons the real it is known for everyone that nowadays the services of the telecommunication networks are being developed day-to-day. The acceptable way of transmission data with the high quality, effect and safety through the network is to use the packet switching in the network. The main part of telecommunication networks is considered communication links. Through these communication links the information in the shape of packets is transmitted and during the transmission these packets pass some intermediate nodes. These intermediate nodes contain routers or switches, etc. By those intermediate nodes a lot of packet streams coming to the different nodes pass and in order not to be served to them at the same time the packets are curried in buffer in a queue. Then they are served in turn. In this condition packet loss and delay processes occur at intermediate nodes and this induces the decrease of the quality of service (QoS) in the network. This paper deals with the processes of packet losses occured in telecommunication networks in detail. Moreover, while researching the processes of packet losses, this network is modeled in AnyLogic program.
Abstract: This paper deals with assessing and comparisons the real it is known for everyone that nowadays the services of the telecommunication networks are being developed day-to-day. The acceptable way of transmission data with the high quality, effect and safety through the network is to use the packet switching in the network. The main part of telecommun...
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Microstructural Characterization of Ti20Zr20Cu40Ni20 Metallic Glass
Panugothu Rama Rao,
Anil Kumar Bhatnagar,
Bhaskar Majumdar
Issue:
Volume 2, Issue 1, June 2018
Pages:
6-10
Received:
13 March 2018
Accepted:
28 March 2018
Published:
4 May 2018
Abstract: In the present investigation, we present our results on characterization of Ti joints, brazed with metallic glass ribbons of Ti20Zr20Cu40Ni20 alloy. Initially, metallic glass ribbons were produced using a vacuum melt spinner and used as filler materials for vacuum brazing of two Ti alloy plates at 1270 K. Field-Emission Scanning Electron Microscopy (FESEM), the as-spun ribbons showed fully amorphous structure when examined on both surfaces by XRD and also verified by TEM investigation. The detailed DSC results revealed that the amorphous phase crystallized at approximately 753K. The brazing joint of two Ti-plates using the metallic glass ribbon was found to be very sound. FESEM characterization of the cross-sectioned brazing joint shows sub-micron size grains uniformly distributed in the matrix with brighter appearance. EDX analysis revealed that the sub-micron grains are rich in Ti, while the matrix phase has Zr-enrichment. Back Scattered Electron (BSE) image also suggested substantial reaction of the brazing ribbon with Ti plates, whose typical lath microstructure is modified to nanostructured lamellar eutectic microstructure comprising of Ti-rich and Zr-enriched phases.
Abstract: In the present investigation, we present our results on characterization of Ti joints, brazed with metallic glass ribbons of Ti20Zr20Cu40Ni20 alloy. Initially, metallic glass ribbons were produced using a vacuum melt spinner and used as filler materials for vacuum brazing of two Ti alloy plates at 1270 K. Field-Emission Scanning Electron Microscopy...
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Locate Objects Mechanical Damage Based on Fiber-Optic Communication Systems
Rakhimov Baxtiyorjon Ne’matovich,
Alimjonov Botirjon Abdulmaqsud O’g’li
Issue:
Volume 2, Issue 1, June 2018
Pages:
11-14
Received:
28 February 2018
Accepted:
26 March 2018
Published:
7 May 2018
Abstract: This work is devoted to the development of a method for monitoring the stability of hydraulic structures (dams), which created a monitoring system, operator can make a conclusion about the reliability of controlled structures as well as data on the level of protection facilities and experimental results are presented.
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Synthesis and Characterization of Sustainable Man-Made Low Cost Clay Bricks with Bamboo Leaf Ash
Pius Rodney Fernando,
Gayan Lakpriya Kannangara,
Gamage Prasad Buddhika,
Asmathul Urushiya
Issue:
Volume 2, Issue 1, June 2018
Pages:
15-22
Received:
15 March 2018
Accepted:
30 March 2018
Published:
9 May 2018
Abstract: This studies investigated a few engineering properties of the effect of bamboo leaf ash blended with brick clay. The bamboo leaves used for this study have been gathered in the agricultural farm, Eastern University, Sri Lanka and the brick clay was acquired from Verpavettuvan, on the depth of 1 to 1.5 m beneath the earth surface. The leaves have been cleaned, sun-dried, burnt in an open environment and then bamboo leaf ash (BLA) has been obtained by heating in a muffle furnace at 600°C for 2 hours. Physical and chemical properties of BLA blended brick has been performed according to British and Indonesian Standard Specifications BS and SNI respectively. The chemical test showed that the total combination of Silica Oxide (SiO₂), Aluminum oxide (Al₂O₃) and Ferrous oxide (Fe₂O₃) content in BLA became above 70% minimal fashionable requirement targeted with the aid of ASTM (ASTM C 618, 2008) for pozzolanic substances. Sex type of BLA blended clay bricks have been manufactured at 0%, 2%, 4%, 6%, 8% and 10%. A complete of 72 bricks comprising of 7 bricks for each percentage of the clay bricks of size 185 mm x 85 mm x 65 mm. Those bricks have been cast with the addition of water-clay ratio of 0.6 to 0.8 to structure a very good workability. Then the green bricks have been mould, dried for 2 days underneath sunlight, baked and physical properties analysed. The analyses of average density, average water absorption, average compressive strength and average flexural strength of the fired clay brick blended with 8 % bamboo leaf ash (BLA) are 1129 kg.m-3, 21.5%, 70 kg.cm-2 and 0.56 kg.cm-2 respectively. These physical properties have been compared with the c control brick purely manufactured from clay. From the results, clay-BLA bricks are perceptibly better than the control brick; those are available in the Eastern region markets.
Abstract: This studies investigated a few engineering properties of the effect of bamboo leaf ash blended with brick clay. The bamboo leaves used for this study have been gathered in the agricultural farm, Eastern University, Sri Lanka and the brick clay was acquired from Verpavettuvan, on the depth of 1 to 1.5 m beneath the earth surface. The leaves have be...
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Natural Ventilation of Smoke Subject to Wind Pressure Within Fire Safety Engineering Approach
Rachid Fakir,
Noureddine Barka,
Jean Brousseau
Issue:
Volume 2, Issue 1, June 2018
Pages:
23-31
Received:
17 August 2018
Accepted:
3 September 2018
Published:
25 September 2018
Abstract: This paper presents an analytical model able to explore the design method of natural smoke evacuation through an exhaust vent subject to wind pressure. The proposed model can be used to determine the flow rate of smoke and the optimal section of the exhaust vent according to the geometric parameters of the room, the heat release rate and the pressure exerted by the wind forces at the exhaust vent. The numerical resolutions of the mathematical equations of the model were performed using the dichotomy method. The proposed analytical approach is built progressively by, (i) the examination of interaction forces between buoyancy forces and wind pressure forces, (ii) a numerical validation of the analytical model using the numerical simulation software Fire Dynamics Simulator, and (iii) proposal of a method of approximation of the optimal section of the exhaust vent for a maximum smoke evacuation rate. The results show very satisfactory and provide adequate prediction of the optimal size of the exhaust vent between the theoretical approximation and various configurations of numerical simulation. The feasibility and effectiveness of the proposed approach lead to an accurate and reliable analytical model able to analyze the influence of the size of natural smoke evacuation vents subjected to the pressure of wind forces.
Abstract: This paper presents an analytical model able to explore the design method of natural smoke evacuation through an exhaust vent subject to wind pressure. The proposed model can be used to determine the flow rate of smoke and the optimal section of the exhaust vent according to the geometric parameters of the room, the heat release rate and the pressu...
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