Different Transmission Control Protocol Variants in Wireless Environments

Computer networks have experienced an explosive growth over the past few years, which has lead to some severe congestion problems. Reliable protocols like TCP works well in wired networks where loss occurs mostly because of congestion. However, in wireless networks, loss occurs because of bit rates and handoffs too. TCP responds all losses by congestion control and avoidance algorithms, which results in degradation of TCP’s End-To-End performance in wireless networks. This paper discusses different issues and problems regarding use of TCP in wireless networks and provides comprehensive survey of various schemes to improve performance of TCP in Wireless Networks

Hydrodynamic studies of the dual fluidized bed reactor systems for high temperature solid looping cycles

A high temperature solid looping cycle (HTSLC) is a type of chemical process carried out in twin reactor system. The hot solid particles are transferred from first reactor to second reactor and same particles are transferred back to the original reactor in the continuous and endless cyles. The purpose of the solid transfer is either to provide heat to carry out the desired reaction or to regenerate the particle reactivity. In some operations solid transport is required for both purposes. The calcium looping process, steam gasification process and chemical looping combustion are the examples of high temperature solid looping cycles. All these processes are well acknowledged for their potential in carbon capture development. Although these processes differ on the basis of chemistry, they require the use of same reactor system called dual fluidized bed (DFB) system. These HTSLCs are currently under the demonstration phase at pilot scale. A 200 kWth test plant is built at University of Stuttgart to demonstrate calcium looping and sorption enhanced reforming process. This thesis presents hydrodynamic studies carried out on the cold model of the test plant

TCP for Wireless Environments

Computer networks have experienced an explosive growth over the past few years, which has lead to some severe congestion problems. Reliable protocols like TCP works well in wired networks where loss occurs mostly because of congestion. However, in wireless networks, loss occurs because of bit rates and handoffs too. TCP responds all losses by congestion control and avoidance algorithms, which results in degradation of TCP\u27s End-To-End performance in wireless networks. This paper discusses different issues and problems regarding use of TCP in wireless networks and provides comprehensive survey of various schemes to improve performance of TCP in Wireless Networks

Study of Standpipe and Loop Seal Behavior in a Circulating Fluidized Bed for Geldart B Particles

The loop seal aeration effect on the supply side has been studied through small scale CFB experimentation. Parameters affected include inventory allocation and entrainment. The gas velocity in the standpipe is influenced by loop seal aeration and riser velocity. Variation in slugging behavior above and below solid downflow velocity of 0.025 m/s is analyzed and discussed here

Cold Model Investigations of a High Temperature Looping Process in a Dual Circulating Fluidized Bed System

The Calcium Looping process is a promising post-combustion CO2 capture technology. A 200 kWth Dual Circulating Fluidized Bed has been built at IFK, University of Stuttgart. Tests were carried out on a hydrodynamically scaled cold model. Operating parameters have been varied, while the suitability of the 200 kWth design has been prove

Three-dimensional full loop simulation of solids circulation in an interconnected fluidized bed

-D full loop CFD simulation of solids circulation is conducted in a complicated circulating-fluidized bed, which consists of a riser, a bubbling bed, a cyclone and a loop-seal. The effects of operating gas velocity, particle size and total solids inventory on the solids circulation rate are investigated based on the system pressure balance of an interconnected fluidized bed. CFD results indicate that the gas velocity in the riser plays a dominant role in controlling the solids circulation rate, whilst the gas velocity in the pot-seal influences in a narrow operating range. The solids circulation rate is strongly influenced by particle size and total solids inventory, but becomes insensitive to the operating conditions in the bubbling bed when the gas velocity is higher than the minimum fluidization velocity

Economic Productive Characters of Buffaloes in Relation to Management Index

On the basis of individual indices, the productive characters of buffaloes was formulated and it was noticed that the dairy farmers had fair management index (between 71 to 80 %). As regards quantity and quality of milk it was noticed that the milk yield was 5.27, 6.21 and 7.2 kg in group I, II and III respectively. The corresponding fat and SNF contents of milk were 6.17 and 8.75, 6.8 and 8.8 and 7.2 and 9.0 % respectively. It was also noticed that the level of management influenced the production in buffaloes. The production under satisfactory management status was 3 to 4, 4 to 5 and 5 to 7 kg under satisfactory, fair and good management index while it was 10 to 14 kg under very good management index. The milk produced by the buffaloes under all the three herd size groups was meeting out the fat content standard according to PFA rules prescribed for Maharashtra but the milk produced under herd size group I and II did not meet out the standards prescribed for SNF content. [Vet. World 2009; 2(3.000): 98-99

Path Coefficient Analysis of Buffalo Production in Buldana District of Maharashtra

A study entitled “Decomposition analysis of buffalo production in Buldana District was undertaken to ascertain the technological changes in term of breeding, feeding, housing, milking and calf management practices of buffalo. The path coefficient analysis of this study clearly demonstrated that daily milk production in buffaloes was influenced substantially by a single factor i.e management index. A combination of all the management practices in the form of overall management status on the rearing were responsible to influence the daily milk yield. However, rearing of good potential animals, feeding of sufficient amounts of dry and green fodder with required amount of concentrates to fulfill the nutritional requirements could favour the milk production in buffaloes. All these factors exhibited positive direct effect on milk production. The indirect effects were also found in positive direction, resulting a positive significant correlation for these factors. [Vet. World 2009; 2(3.000): 103-104