Analysis and performance prediction of scramjet inlets utilizing a three-dimensional Navier-Stokes code

A series of inlet analysis codes (2-D, axisymmetric, 3-D) were developed which can analyze complicated flow through complex inlet geometries in a reasonably efficient manner. The codes were verified and are being used extensively to analyze practical inlet geometries both at Langley as well as industries. Newly installed VPS 32 computer will allow more complex configurations to be analyzed. Scalar FORTRAN versions are available to increase transportability of the codes for use on other Scalar computers and on the Cray vector processing computer

Modelling of Cascade Fin Aerodynamics Near Stall using Kirchhoff's Steady-state Stall Model

Nonlinear longitudinal aerodynamics associated with cascade fins at high angles of attack near stall has been modelled using Kirchhoff's formulation. Grid fins are a relatively recent development in guided missile technology. In this paper, a new category of grid fins, nomenclatured as cascade fins, has been proposed. In cascade fin design, an appropriate selection of gap-to-chord ratio and the number of planar members lead to desired stall angle and acceptable overall lift coefficient, respectively. Kirchhoff's steady-state stall model has been validated on wind tunnel data generated for Cascade fins having rectangular airfoil cross-section. National Wind Tunnel Facility (NWTF) of IIT, Kanpur, was used to generate the wind tunnel data consisting of the variation of lift coefficient with angle of attack. The cascade fins were tested to generate the data by varying gap-to-chord ratio and number of planar fins. The cascade fins with rectangular cross-section were tested with and without end plates. Kirchhoff's steady-state stall model was applied to wind tunnel data of cascade fins for modelling flow separation point and maximum likelihood method was used to estimate the parameters characterising stall characteristics. The effects of end plates, variation of number of fins and gap-to-chord ratio on parameter estimation were also studied. It has been observed that Kirchhoff's steady-state stall model could advantageously be applied to model nonlinear aerodynamics associated with cascade fins at high angle of attack.Defence Science Journal, 2011, 61(2), pp.157-164, DOI:http://dx.doi.org/10.14429/dsj.61.48

Heterosis for Fruit Yield and its Components in Brinjal (Solanum melongena L.)

An experiment was conducted with 14 parents and 40 F1s to study heterosis in brinjal. Crosses showing significant heterosis over the better parent were: HE12 X Aruna for first fruit set; BR-112 X Aruna for fruit length and diameter; Pant Samrat X Punjab Neelam for number of fruits per plant; H-7 X Aruna for fruit weight; H-9 X S-16 for total yield per plant; Negative heterosis were recorded in KT-4 X Aruna for borer and Pant in Rituraj X Punjab Neelam for nematode infestation

To compare the recovery time of Propofol or Isoflurane in day case procedures

AIM OF THE STUDY: The aim of the study is to compare the recovery times when Propofol or Isoflurane are used for the maintenance of anaesthesia in day case surgery and also to determine which agent is suitable to make the patient home fit at the earliest. MATERIALS AND METHODS: This study was carried out in the General Surgery theatre, Government General Hospital, Chennai after obtaining institutional approval. The aim of the study was to compare the Phase I and Phase II recovery times when Propofol or Isoflurane are used for the maintenance of anaesthesia in day case procedures and also to determine which agent is suitable to make the patient street fit at the earliest. STUDY DESIGN: The study was a randomized prospective study. SELECTION OF CASES: Forty patients undergoing Day Case surgeries in the Head, Breast or Upper limb were selected for the study. Their age ranged from 18 to 47years. All the patients were assessed and those with normal clinical, biochemical radiological and haematological parameters were selected. Informed written consent was obtained from all the patients. Each patient was randomly allocated to either the Propofol or the Isoflurane group by lots. The groups were named ‘P’ for Propofol and ‘I’ for Isoflurane. INCLUSION CRITERIA: 1. Assessed patients of ASA physical status I & II. 2. Normal biochemical and haematological parameters. 3. Age group between 18 to 50 years. 4. ASA class I, II. 5. No known hypersensitivity to eggs or sulpha drugs. 6. Airway MPC 1, 2 and 3. 7. Minor surgeries of head, neck, breasts and upper limb. 8. Surgery lasting less than 90 minutes duration. 9. Patients normally able to ambulate well. 10. Educated attender who can understand and carryout instructions. EXCLUSION CRITERIA: 1. Patient not willing. 2. ASA class III and above. 3. Known hypersensitivity to eggs or sulpha allergy. 4. Airway MPC IV. 5. Major surgeries requiring overnight hospital stay. 6. Surgeries near or involving the airway. 7. Patient having difficulty in walking. 8. No attender or attender not educated enough to carryout instruction. METHODS: Pre-operative preparation: Patients were assessed pre-operatively, procedure was explained to the patient and informed consent obtained. They were assessed with particular attention for any contraindications. The tests for recovery and the importance of strictly following instructions were emphasized. SUMMARY: Early recovery of psychomotor functions and fewer postoperative side effects, such as nausea and vomiting, leads to earlier discharge from the PACU and from the hospital. The use of a TIVA regimen may be an important step toward fast-track eligibility and shortening of PACU stay. This may result in increased efficacy in busy surgical centers. The anesthetic depth was similar both in the propofol group and the Isoflurane group. Occasionally Propofol was associated with some purposeful movements but was not significant enough to delay surgery. Similar problems have been reported previously with Propofol in some studies. These are probably related to the complex relationship between the delivered concentration over time and the resultant blood levels. It may also be due to the wide variability in patient responses at a given plasma concentration of Propofol. This explains the requirement for bolus administration in some of our patients. In spontaneously breathing patients, inadequate anesthesia is manifested by purposeful movements, which allows corrective action to be taken promptly. As a result, awareness is unlikely, and none of our patients recalled intraoperative events. Postoperative pain was well controlled by the combination of non steroidal anti inflammatory drugs and local anesthetic infiltration; additional analgesia was rarely required. Since Fentanyl has been used as an analgesic adjuvant in both groups, there was no difference in the severity of postoperative pain in both the groups. . Both Propofol and Isoflurane seemed to be acceptable agents for spontaneously breathing anesthetized patients, allowing excellent control of the depth of anesthesia without obvious problems. Nevertheless, Propofol did result in more rapid intermediate recovery when compared to Isoflurane. CONCLUSION: On comparing the recovery time and home readiness in Ambulatory Anaesthesia using Propofol as a Total Intravenous Venous Anaesthesia agent and inhalational maintenance technique with Isoflurane, it was found that: 1. Propofol as a sole agent had a quicker recovery. 2. Phase I recovery of both the groups were comparable. 3. Phase II recovery with Propofol TIVA was much shorter than Isoflurane maintenance anaesthesia. 4. The earlier Home Readiness in TIVA using Propofol makes it more advantageous than Isoflurane maintenance in day case surgeries

A Comparitive study between Patients of Small and Large Bowel Perforation managed by Stomas with Drains and Without Drains

INTRODUCTION: Even though studies have proven that usage of drains in patients undergoing ostomy due to perforation was neither effective nor safe but still PRACTICE OF PLACING A DRAIN IS FOLLOWED MANY A TIMES. Drains are placed in view to detect haemorrhage, intra-abdominal pus, reactive effusion, detect leak,surgeons satisfaction. At the same time, there are many drain related complications like infection, omental prolapse, DT related adhesions, DT site hernia For these reasons this comparative study was conducted whether we need drain or not in patients with small and large bowel perforation managed by ostomies METHODS: • Written informed consent will be obtained from all subjects before enrolment in the study • All patients are thoroughly examined. • Patients were divided into two groups into GROUP A and GROUP B by randomization. • Group A patients will receive drain tube and group B will not receive drain tube. • All patients were regularly examined post operatively regarding complications. • All patients were followed up for a period of three months. • All details regarding the study will be recorded according to the pre designed proforma The factors monitored in both the group of patients are DT site pain, DT site infection, DT site omental prolapse, DT site hernia, Postoperative mobility of patients, Number of patients undergoing re surgery, Duration of hospital stay, Operative site wound infection, Other DT unrelated post-op complications RESULTS: The observations are plotted in the above plotted graphs and tables. It shows there is no statistical difference in DT unrelated complications like wound infection, abscess, electrolyte imbalance and burst abdomen even though percentages between two groups vary. Also there is no statistical difference in mobility of patient, number of patients undergoing re surgery and duration of hospital stay between the two groups. But in drain tube patients a good number of drain related complications occur like DT site pain, DT site infection, DT site hernia and DT site omental prolapse. The drain tube site pain occurred in 60%, the drain tube site infection occurred in 16%, the drain tube site hernia occurred in 8% and the drain tube site omental prolapse in 4% patients. Even though the drain unrelated complications is not statistically significant between two groups, the patients with drain tubes had drain related complications which affected the post op period without affecting other complications, mobility and duration of hospital stay. From this we understood that KEEPING A DRAIN for a small and large bowel perforative peritonitis patient managed by ostomy is of NO USE and in turn it causes less significant DT related complications which should be avoided. So surgical drains should be used as when needed. CONCLUSION: In small bowel and large bowel perforation with peritonitis (excluding duodenal perforation) patients managed by ostomies (stoma) DRAIN TUBES DOESN’T play an important role in the post- operative period, instead it causes unnecessary drain related complications. The mobility of patient, rates of re surgery, drain unrelated complications and duration of hospital stay is NOT AFFECTED by drain tube

Experimental Investigation on the Cold – Formed Steel – Concrete Composite Beam Under Flexure

Steel – concrete composite members are widely used in the construction of multistorey buildings and bridges. Composite construction takes the advantages of steel and concrete, in turn reduces the cost of construction. This paper discuss the use of galvanised steel with concrete as composite beam under flexural loading. Six specimens were tested to failure with varying number of headed stud connectors from 0 to 5. Load carrying capacity of the composite beam specimen improved by 62 % as compared to beam without shear connectors. The mode of failure of the composite beam is mainly due to failure of the shear connectors at tension zone, which leads to formation of multiple cracks on concrete portion. The analytical model was developed using finite element software ANSYS and found to obtain similar result as compared to the experimental results with minimal variation in the central deflection

Studies on Combining Ability for Yield and Quality Traits in Brinjal (Solanum melongena L.)

The experimental material in brinjal (eggplant) comprised 19 parents (15 lines + 4 testers), 60 F1 crosses and two standard checks (BH-1 and BH-2). This was grown in Randomized Block Design, with three replications. Lines vs. testers showed significance for all characters except plant height, plant spread, number of primary branches, dry matter, total sugars and total phenol. Analysis for parents vs. hybrids showed significance for all the characters except average fruit weight, number of fruits per plant, plant spread and number of primary branches. Analysis of Variance for combining ability revealed mean squares due to lines and testers were significant for all the characters except plant height, plant spread, number of primary branches, total sugars, total phenol and content of anthocyanins. The ratio of variance due to specific combining ability and general combining ability (σ2SCA: σ2GCA) was greater than unity, indicating non-additive genetic control for all traits except plant spread and total phenols. Among the females, Punjab Barsati, PBR-91-1, RCMBL-1-1, BSR-11; and among the males, BB-93-C and U-8-61-3 were best general combiners for yield and yield components. Punjab Barsati was the best combiner for days to 50% flowering, days to first fruit harvest, number of fruits per plant and number of primary branches. The cross JBR-3-16 × PB-64 manifested best SCA effects for days to 50% flowering; PBR-91-1JBSR-98-2 for average fruit weight; BSR-11 × PB-64 for fruit length; BSR-11× U-8-61-3 for fruit girth, and the cross HABL-1 × JBSR-98-2 for yield per plant and per hectare