Integrity Assessment of LCA Drop Tank under Internal Cyclic Pressure

A facility and expertise has been developed at NAL to conduct automated internal pressure cycling tests. The hardware and instrumentation includes capturing of pressure on the data logger along with strain gage data. Digital data can be recorded continuously during entire pressure cycle, thus enabling to provide comparative view of reduction in stiffness, if any,in terms of graphs. The Maximum Pressure up To Which the Central Shells Could Be Tested Was 188 .5psi. A Maximum Strain Of 5166 Micro Strains, At A Pressure Of 188 .5psi, Was Found Near The GFRP Bulkhead In The Circumferential Direction. The Integrity Of The Bulkhead Joint Appears Satisfactory. The Nose-Cone, Tested For Internal Pressure Cycling Between 3 And L Lpsi Did Not Show Any Leaks Anywhere On The Surface Or From The Filler Cap . However, After 1104 Pressure Cycles,The End Flange Failed With A Loud Pop.On Inspection, It Was Found That The Failure Is Due To Improper Adhesion Between The GFRP Base Material And The Aluminum Ring Holding The End-Flange. Subsequently, This Ring Was Joined To The GFRP Shell By Bolts And The Pressure Cycling Was Continued For A Further 5000 Cycles,As Required, Without Any Failure/Leaks Anywhere On The Nose Cone. The Nose Cone Was Then Subjected To A Steadily Increasing Pressure To Verify The Residual Strength.At About 60psi, Leaks Were Observed Around The Filler Cap And The Pressure Was Continued Up To 85psi . At This Pressure, The Filler Cap Seal Gave-Up And A Profuse Leak Sprouted Around The Cap This Was Verified Again By Replacing The Filler Cap With A New One That Also Failed Completely At About 85psi Pressure. Presently,It May Be Concluded That The Lca s Gfrp Drop Tank Internal Bulkheads Of Central Shell Can Withstand A Pressure Of 185psi And The Weak Link,In The DT Assembly, Is The Filler Cap Seal That Can Stand A Pressure Of Only 60psi

On a large sample test for the traffic intensity in GI|G|s queue

A large sample test based on normal approximation for the traffic intensity parameter ρ in the cases of single and multiple-server queues has been proposed. The test procedure is developed without imposing steady-state assumptions and is applicable to queueing systems with general interarrival and service-time distributions

Snow cover, snowmelt and runoff in the Himalayan River basins

Not withstanding the seasonal vagaries of both rainfall amount and snowcover extent, the Himalayan rivers retain their basic perennial character. However, it is the component of snowmelt yield that accounts for some 60 to 70 percent of the total annual flow volumes from Hamilayan watersheds. On this large hydropotential predominantly depends the temporal performance of hydropower generation and major irrigation projects. The large scale effects of Himalayan snowcover on the hydrologic responses of a few selected catchments in western Himalayas was studied. The antecedent effects of snowcover area on long and short term meltwater yields can best be analyzed by developing appropriate hydrologic models forecasting the pattern of snowmelt as a function of variations in snowcover area. It is hoped that these models would be of practical value in the management of water resources. The predictability of meltwater for the entire snowmelt season was studied, as was the concurrent flow variation in adjacent watersheds, and their hydrologic significance. And the applicability of the Snowmelt-Runoff Model for real time forecast of daily discharges during the major part of the snowmelt season is examined

Water-saving Rice Production Technologies in Krishna Western Delta Command of Andhra Pradesh – An Economic Analysis

The economic analysis of water-saving rice production technologies, viz. system of rice intensification (SRI), semi-dry and rotational irrigation vis-à-vis farmers’ practice has been carried out based on the study executed in Modukuru pilot area of Guntur district of Andhra Pradesh. Among the three water-saving rice production technologies analyzed, the total cost of cultivation has been recorded highest in SRI (Rs 58645/ha), followed by rotational (Rs 47140/ha) and semi-dry (Rs 39321/ha). But, the per hectare yield has been found highest in SRI (6.85 t), followed by semi-dry (6.66 t) and rotational (6.2 t), inferring that all the three technologies have recorded higher yields over farmers’ practice of 5.5 t/ha. However, the net returns and B-C ratio are maximum in semi-dry (Rs 43,484/ha; 1.11), followed by rotational (Rs 30,085; 0.64) and SRI (Rs 26,466/ha; 0.45) methods. Similarly, the water-use efficiency has been found highest in SRI (8.53 kg/ ha-mm), followed by semi-dry (8.02 kg/ha-mm) and rotational (7.33 kg/ ha-mm) methods, while the water-use efficiency benefit (Rs/ha-mm) has been recorded maximum in semi-dry (52.39), followed by SRI (42.08) and rotational (35.56) methods. With the initiation of Andhra Pradesh Water Management Project, Bapatla, the area under semi-dry rice cultivation has been found increasing over a period of four years, from 0.6 ha in 2004-2005 to 22 ha in 2007 -2008.Agricultural and Food Policy,

Economic analysis of prawn culture in Andhra Pradesh - Some preliminary findings

Inadaquate supply of quality seed is one of the chief constraints that impedes the quick development of ptawn culture. Estuaries still remain the largest source of prawn seed supply. They are likely to remain so atleast for sometime in offing before the hatchery production of seeds is undertaken commercially and massively. The Marine Products Export development Authority assists the prawn farmers in setting up prawn seed banks by providing technical assistance on prawn culture, undertaking site selection and farm surveys, preparing project reports for submitting to the banks to get financial assistance, releasing subsidy to the tune of 16% on the capital cost of the project and providing continued technical assistance throughout the culture period. Already some prawn farmers have started establishing such prawn seed banks and supplying prawn seed commercially. This paper presents and discusses results of case studies on the economic feasibility of setting up prawn seed banks by fish farmers/prawn farmers

Spectra of some new graph operations and some new classes of integral graphs

In this paper, we define duplication corona, duplication neighborhood corona and duplication edge corona of two graphs. We compute their adjacency spectrum, Laplacian spectrum and signless Laplacian. As an application, our results enable us to construct infinitely many pairs of cospectral graphs and also integral graphs. Keywords: Duplication corona, Duplication edge corona, Duplication neighborhood corona, Cospectral graphs, Integral graphs