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781.
782.
Hyeong Lee Chong Un 《Communications, IEEE Transactions on》1985,33(8):809-819
In this paper the performances of four statistical voice/data multiplexers are analyzed and compared. The structures of these multiplexers are based on the newly proposed queueing, frame management, and integrated flow control methods. For the queueing purpose, two separate finite voice and data buffers are used to queue voice and data packets independently. For frame management, four versions of master frame management are considered. As for the integrated flow control algorithm, speech coding techniques such as variable rate coding and embedded coding are considered. To evaluate the performances of the multiplexers, analytical formulations are made from the equivalent queueing models of the proposed systems. Then, numerical results on the performance of the multiplexers are obtained by using the Gauss-Seidel iteration method. These results show that there exist tradeoffs between data and voice traffic performances for a given input traffic load and the output channel rate. 相似文献
783.
Rupsankar Chakrabarti & Badiveddy Madhusudana Rao 《International Journal of Food Science & Technology》2008,43(1):179-184
The annual inland fish production in India is 3.2 million tonnes and above. Aquaculture is around 80% of total inland fish production. The enhanced aquaculture production demands alternate processing methods for better utilisation of the farmed fish. Cirrhinus mrigala is one of the dominated species among cultured Indian major carps, but rated with lowest price. Fish meat with good gel‐forming capacity is a prerequisite in the production of fast‐moving fabricated analogue product. Cirrhinus mrigala had the highest gel strength, i.e. 435 gcm of its fresh meat in comparison with other carps. Apart from the highest protein and salt‐soluble protein nitrogen content in fresh C. mrigala meat, this article also reports that the presence of the darkest thick band of myosin heavy chain and actin in the polyacrylamide gel electrophoresis pattern of salt‐soluble extract of C. mrigala might be another possible reason for the highest gel strength in comparison with other carps. Cirrhinus mrigala contained white meat around 90%. This carp could be suitably used in the preparation of high‐valued fabricated analogue product. 相似文献
784.
Results of an investigation dealing with the behaviour of grid-connected induction generators (GCIGs) driven by typical prime movers such as mini-hydro/wind turbines are presented. Certain practical operational problems of such systems are identified. Analytical techniques are developed to study the behavior of such systems. The system consists of the induction generator (IG) feeding a 11 kV grid through a step-up transformer and a transmission line. Terminal capacitors to compensate for the lagging VAr are included in the study. Computer simulation was carried out to predict the system performance at the given input power from the turbine. Effects of variations in grid voltage, frequency, input power, and terminal capacitance on the machine and system performance are studied. An analysis of self-excitation conditions on disconnection of supply was carried out. The behavior of a 220 kW hydel system and 55/11 kW and 22 kW wind driven system corresponding to actual field conditions is discussed 相似文献
785.
786.
787.
N. Muthukrishnan M. Murugan K. Prahlada Rao 《The International Journal of Advanced Manufacturing Technology》2008,38(5-6):447-454
The paper attempts to study the machinability issues of aluminium-silicon carbide (Al-SiC) metal matrix composites (MMC) in turning using different grades of poly crystalline diamond (PCD) inserts. Al-SiC composite containing 15%wt of SiC was used as work material for turning and PCD inserts of three different grades were used as cutting tools. Experiments were conducted at various cutting speeds, feeds and depth of cuts and parameters, such as surface roughness, specific power consumed, and material removal rate were measured. The worn surface of the insert was examined by scanning electron microscope (SEM). The surface finish observed was found to be much lower than the theoretical surface roughness. The influence of cut was examined for the different grades of PCD inserts. It was observed that the 1600 grade PCD inserts performed well from the surface finish and specific power consumption points of view closely followed by the 1500 grade. 相似文献
788.
The need for a rapid expansion in irrigation in India for the purposes of food production is generally accepted. Whether irrigation works can at the same time effectively tackle the country's massive rural unemployment problem is the subject of this paper. Basic planning requirements are outline, and then the complex issues surrounding the choice of labour‐intensive or capital‐intensive technology are discussed. Finally, the kinds of data required before informed decisions can be made are specified. 相似文献
789.
Post-buckling analysis of a uniform cantilever column under a tip concentrated subtangential follower force has been studied.
The solution of the problem is obtained in terms of elliptic integrals. The load deflection curves are presented. 相似文献
790.
利用等离子活化技术对93W/Ni/Mo1进行真空扩散焊接,用剪切强度和显微硬度表征焊接接头的力学性能,对焊接界面和接头断口物相及微观结构进行表征分析。结果表明,焊接温度低于800℃时,焊接界面有孔洞,焊接温度高于800℃时,焊接界面良好。焊接接头的剪切强度随着焊接温度的升高先升高后降低,在焊接温度为800℃时接头强度最大为100.2 MPa。焊接温度低于800℃时,焊接界面发生扩散形成固溶体;焊接温度高于800℃时,Ni/Mo1界面生成MoNi高硬度金属间化合物,降低焊接接头结合强度。93W/Ni/Mo1焊接接头的断裂破坏主要发生在Ni/Mo1扩散界面。 相似文献