Comfort Level Refinement of Military Tracked Vehicle Crew through Optimal Control Study

Military tracked vehicle and crew are modelled together in this paper as integrated man-machine lumped parameter model, by integrating the simplified 5 degrees of freedom (DoF) tracked vehicle model, including seat and 4 DoF human bio-dynamic model, thus resulting in a 9 DoF simplified vehicle-occupant model. Then the natural frequency of major mass segment namely the chassis mass is obtained through simulation study, for a known road input. The value obtained is compared with that of an earlier research work, for validation of said man-machine model. Then focusing our study locally at crew seat location, parameters of crew seat suspension for ride comfort are optimised using the optimal digital state space controller designed for this purpose by implementing it in a 2 DoF occupant - seat suspension model and its Simulink model constructed. Simulation results illustrate the attainment of the goal by meeting the controller design requirements

Ergonomic Level Improving of Armoured Fighting Vehicle Crew

The armoured fighting vehicle (AFV)-occupant composite system is modelled as a lumped parameter system, in this paper, wherein the 4 degrees of freedom (dof) biodynamic occupant model is integrated with 10 dof in-plane AFV model including the crew seat, thus leading to the 14 dof vehicle-occupant composite model and the governing equations of motion are obtained. The composite model is subjected to idealised road input simulating the ground reaction forces. Natural frequencies and the frequency domain vibration responses of various masses of model are obtained. The natural frequency of chassis thus obtained is compared with the result established by an earlier research work, to validate the model. The study is focused on crew seat location. A 2 dof occupant-seat suspension model is formulated and validated through case study. The optimised values of seat suspension parameters for ride comfort are obtained using the said model, through two methods of Invariant points theory and genetic algorithm toolbox of Matlab 2014a software. Acceleration responses of body for the current and optimised parameter values obtained illustrate that comfort of crew is improved with optimised values through minimization in the acceleration responses

Impaired Maternal Hemodynamics in Morbidly Obese Women: A Case-control Study.

AIM: Maternal obesity is associated with significant pregnancy complications and is a risk factor for the development of hypertensive disorders of pregnancy as well as other adverse outcomes. There are few data regarding the hemodynamic aberrations observed in maternal obesity. The aim of this study was to investigate maternal hemodynamics in morbidly obese pregnant women. METHODS: This was a prospective, case-control study of morbidly obese women (BMI >40 kg/m(2) ) and controls (BMI 20-29.9 kg/m(2) ) at a ratio of one-to-ten. The control population was matched for maternal age and gestational age. BMI was calculated based on maternal height and weight at the time of recruitment to the study, which occurred on the same day as the hemodynamic assessment. Pregnant women in the second or third trimester of pregnancy were included. Women who were found to be hypertensive at any time were excluded from the study. USCOM-1A(®) was used to assess hemodynamic parameters (heart rate, stroke volume, cardiac output and systemic vascular resistance). The parameters were corrected for body surface area (BSA) to provide the stroke volume index (SVI), cardiac index (CI) and systemic vascular resistance index (SVRI). Mann Whitney-U test was used to compare the medians of the hemodynamic variables between the two groups. RESULTS: A total of 30 obese women and 327 controls were recruited. There was no difference in maternal (p = 0.506) or gestational (p = 0.693) age at recruitment between the groups. Mean arterial pressure was higher both at pregnancy booking (90 vs 80 mmHg, p < 0.001) and study recruitment (91 vs 85 mmHg, p < 0.001) in the obese group. Heart rate was higher in the obese group (p = 0.003), however there was no difference in stroke volume (p = 0.271), cardiac output (p = 0.238) or systemic vascular resistance (p = 0.635). Following correction of these parameters for BSA, the SVI (34 vs 45 ml/m(2) , p < 0.001) and CI (2.96 vs 3.64 L/min/m(2) , p < 0.001) were significantly reduced in the obese group, whilst the SVRI was significantly higher (2354 vs 1840 dynes-sec-cm(5) /m(2) , p < 0.001). CONCLUSION: The findings of our study suggest that cardiac function is significantly altered in morbidly obese pregnant women. In order to make appropriate comparisons between individuals, it is imperative that hemodynamic parameters are indexed for BSA - as indeed they are in pediatric cardiology. The novel finding of a reduced CI in morbidly obese pregnant women may explain the predisposition to preeclampsia and other adverse outcomes in this population and warrants further investigation

Antidiabetic activity of Manomani chooranam aqueous extract on female wistar albino rats

Background: The aim of the present study was to evaluate the antidiabetic potential of Manomani chooranam (MMC), an indigenous polyherbal siddha formulation in Streptozotocin (STZ) induced diabetic female Wistar albino rats.Methods: Aqueous extract of MMC was prepared. Wistar albino rats were divided into six groups (n=6). Group 1 was kept as normal control, Group 2, 3, 4, 5 and 6 were induced diabetes. After induction, the group 2 was kept as diabetes control; Group 3 received the standard drug metformin (100 mg/kg), whereas Groups 4, 5 and 6 were treated with the aqueous extract of MMC at 500 mg/kg, 1000 mg/kg and 1250 mg/kg doses, respectively for the 21 days. Blood sugar was estimated at the end of each week. At the end of the study, rats were sacrificed and the pancreas was analyzed for histopathological changes. Data expressed as mean±standard error of the mean. Statistical analysis was done using one-way ANOVA followed by post hoc Tukey's test. p<0.05 considered statistically significant.Results: The groups which received aqueous extract of MMC at 500 mg/kg, 1000 mg/kg and 1250 mg/kg showed a significant decrease in the mean blood sugar level when compared to normal level. The groups which received MMC shows significant reduction in blood sugar level in comparison with standard drug metformin 100 mg/kg.Conclusions: The aqueous extract of MMC was able to decrease the elevated blood sugar levels in dose dependent manner

Acoustical & thermodynamic properties of some ternary systems of 1-pentanol in n-hexane solution with various organic compounds using ultrasonic technique

943-952The thermo-physical parameters like density, ultrasonic velocity and viscosity have been experimentally measured for the ternary liquid mixtures of 1-pentanol with N,N dimethyl formamide (N,N-DMF) / o-methoxy phenol or 2-methoxy phenol (OMP) / m-methoxy phenol or 3-methoxy phenol (MMP) in n-hexane medium at various temperatures like 303 K, 308 K and 313 K. Certain acoustical and thermodynamic parameters such as cohesive energy, available volume, viscous relaxation time, Lennard Jones potential, free energy of activation, Gibb’s free energy and entropy are calculated from the experimental data. The variation of these parameters with respect to different concentrations ranging from 0.001 M to 0.01 M at different temperatures viz. 303 K, 308 K and 313 K and at fixed frequency of 2 MHz for the three ternary systems namely OMP + 1-pentanol+n-hexane, N,N-DMF+ 1-pentanol+n-hexane and MMP + 1-pentanol+n-hexane have been discussed in terms of molecular interactions under the influence of ultrasonic sound. The role of thermodynamic parameters in the stability of the charge transfer complexes and the hydrogen bonded complexes are predicted

Acoustical &amp; thermodynamic properties of some ternary systems of 1-pentanol in n-hexane solution with various organic compounds using ultrasonic technique

The thermo-physical parameters like density, ultrasonic velocity and viscosity have been experimentally measured for the ternary liquid mixtures of 1-pentanol with N,N dimethyl formamide (N,N-DMF) / o-methoxy phenol or 2-methoxy phenol (OMP) / m-methoxy phenol or 3-methoxy phenol (MMP) in n-hexane medium at various temperatures like 303 K, 308 K and 313 K. Certain acoustical and thermodynamic parameters such as cohesive energy, available volume, viscous relaxation time, Lennard Jones potential, free energy of activation, Gibb’s free energy and entropy are calculated from the experimental data. The variation of these parameters with respect to different concentrations ranging from 0.001 M to 0.01 M at different temperatures viz. 303 K, 308 K and 313 K and at fixed frequency of 2 MHz for the three ternary systems namely OMP + 1-pentanol+n-hexane, N,N-DMF+ 1-pentanol+n-hexane and MMP + 1-pentanol+n-hexane have been discussed in terms of molecular interactions under the influence of ultrasonic sound. The role of thermodynamic parameters in the stability of the charge transfer complexes and the hydrogen bonded complexes are predicted