Factors contributing to the Success of Aquaculture Field Schools

ICAR- Central Institute of Freshwater Aquaculture (CIFA) had piloted four Aquaculture Field Schools (AFS), a model of farmer to farmer extension, in Odisha and Chhattisgarh states in India. The AFS’ are attracting farmers and stakeholders as they provide a platform to share experience and enable cross learning. In this research, an attempt has been made to identify the factors that contribute to the successful performance of AFS. Data were collected from 166 user farmers, selected randomly from the list available with operators. Five variables viz., age of fish farmer, frequency of visit to AFS, duration of visit, interaction with the fellow farmers and advocation of advanced technologies of ICAR-CIFA to other farmers were observed to be significantly contributing to yield of fish. The Multiple correlation coefficient, R=0.48, indicated that there is a significant and positive correlation between the observed and predicted value of fish yield

Design and simulation of a thermo transfer type MEMS based micro flow sensor for arterial blood flow measurement

Thermo transfer type MEMS (Micro Electro Mechanical System) based micro flow sensing device have promising potential to solve the limitation of implantable arterial blood flow rate monitoring. The present paper emphasizes on modeling and simulation of MEMS based micro flow sensing device, which will be capable of implantable arterial blood flow rate measurement. It describes the basic design and model architecture of thermal type micro flow sensor. A pair of thin film micro heaters is designed through MEMS micro machining process and simulated using CoventorWare; a finite element based numerical code. A rectangular cross section micro channel has been modeled where in micro heater and thermal sensors are embedded using the same Coventor-Ware tools. Some promising and interesting results of thermal dissipation depending upon very small amount of flow rate through the micro channel are investigated. It is observed that measuring the variation of temperature difference between downstream and upstream, the variation of fluid flow rate in the micro channel can be measured. The numerical simulation results also shows that the temperature distribution profile of the heated surface depends upon microfluidic flow rate i.e. convective heat transfer is directly proportional to the microfluidic flow rate on the surface of the insulating membrane. The simplified analytical model of the thermo transfer type flow sensor is presented and verified by simulation results, which are very promising for application in arterial blood flow rate measuring in implantable micro devices for continuous monitoring of cardiac output

Hardware Software Partitioning of Multifunction Systems

The problem of hardware-software partitioning for systems that are being designed as multifunction systems is addressed. Simulated annealing is known to generate very good solutions for most optimization problems, however the running time of this algorithm can be very high. We apply a modified simulated annealing approach to the partitioning problem resulting in a smaller search space, yet yielding good partitions. We show experimental results that yield better solutions in comparison to the existing multifunction partitioning approaches within acceptable running time

Optimal Feet-Forces’ and Torque Distributions of Six-Legged Robot Maneuvering on Various Terrains

An analytical model with coupled dynamics for a realistic six-legged robotic system locomoting on various terrains has been developed, and its effectiveness has been proven through computer simulations and validated using virtual prototyping tools and real experiment. The approach is new and has not been attempted before. This study investigated the optimal feet-forces’ distributions under body force and foot–ground interaction considering compliant contact and friction force models for the feet undergoing slip. The kinematic model with 114 implicit constraints in 3D Cartesian space has been transformed in terms of generalized coordinates with a reduced explicit set of 24 constrained equations using kinematic transformations. The nonlinear constrained inverse dynamics model of the system has been formulated as a coupled dynamical problem using Newton–Euler method with realistic environmental conditions (compliant foot–ground contact, impact, and friction) and computed using optimization techniques due to its indeterminate nature. One case study has been carried out to validate the analytical data with the simulated ones executed in MSC.ADAMS® (Automated Dynamic Analysis of Mechanical Systems), while the other case study has been conducted to validate the analytical and simulated data with the experimental ones. In both these cases, results are found to be in close agreement, which proves the efficacy of the model

Computer aided modeling and analysis of turning motion of hexapod robot on varying terrains

To successfully design a hexapod robot with maneuverability over varying terrains, the kinematic and dynamic analyses for its motion are very essential. This paper proposes an integrated approach for carrying out design, analysis and simulation of the motions and mechanisms of hexapod robots generating turning gaits. A new path planning approach is proposed for the turning motion analysis of the robot walking over any kind of terrain varying from flat to rough in three-dimensional Cartesian space with the desired gait pattern. The kinematics model of the hexapod robot having legs of three degrees of freedom each is developed to simulate turning motion, and its performance is tested on a realistic computer aided design model using the available virtual prototyping tools. The model is capable of investigating various kinematic parameters of the hexapod robot like displacement, velocity, acceleration, trace of the position of aggregate center of mass during turning motions. A case study is solved and the theoretically obtained results are verified by simulating the same in a commercially available numerical solver for multibody dynamic analysis like MSC.ADAMS®. The results show a close agreement between the theoretical and simulated results, which proves the efficacy of the proposed algorithm

Study on feet forces' distributions, energy consumption and dynamic stability measure of hexapod robot during crab walking

This paper deals with the development of a dynamical model related to crab walking of a hexapod robot to determine the feet forces' distributions, energy consumption and dynamic stability measure considering the inertial effects of the legs on the system, which has not been attempted before. Both forward and inverse kinematic analyses of the robot are carried out with an assigned fixed global frame and subsequent local frames in the trunk body and joints of each leg. Coupled multi-body dynamic model of the robot is developed based on free-body diagram approach. Optimal feet forces and corresponding joint torques on all the legs are determined based on the minimization of the sum of the squares of joint torques, using quadratic programming (QP) method. An energy consumption model is developed to determine the minimum energy required for optimal values of feet forces. To ensure dynamically stable gaits, dynamic gait stability margin (DGSM) is determined from the angular momentum of the system about the supporting edges. Computer simulations have been carried out to test the effectiveness of the developed dynamic model with crab wave gaits on a banking surface. It is observed that when the swing leg touches the ground, impact forces (sudden shoot outs) are generated and their effects are also observed on the joints of the legs. The effects of walking parameters, namely trunk body velocity, body stroke, leg offset, body height, crab angle etc. on power consumption and stability during crab motion for duty factors (DFs) like 1/2, 2/3, 3/4 have also been studied

Modeling and Simulation of Wave Gait of a Hexapod Walking Robot: A CAD/CAE Approach

In the present paper, an attempt has been made to carry out dynamic analysis of a hexapod robot using the concept of multibody dynamics. A CAD (Computer Aided Design) model of a realistic hexapod robot has been made for dynamic simulation of its locomotion using ADAMS (Automatic Dynamic Analysis of Mechanical Systems) multibody dynamics solver. The kinematic model of each leg of three degrees of freedom has been designed using CATIA (Computer Aided Three Dimensional Interactive Application) and SimDesigner package in order to develop an overall kinematic model of the robot, when it follows a straight path. Joint Torque variation as well as the variation of the aggregate center of mass of the robot was analyzed for the wave tetrapod gait. The simulation results provide the basis for developing the control algorithm as well as an intelligent decision making for the robot while in motion

Outcomes of Pediatric Neurosurgical Cases Managed by General Neurosurgeons: A Retrospective Study from Eastern India

Background India is home to almost 19% of the world's children. The burden of diseases in the pediatric age group is quite high and is just the tip of the iceberg. In India, there are very few neurosurgeons who deal with cases in the pediatric age group. Most parents avoid surgical management for their child due lack of confidence in the expertise of the neurosurgeon in handling pediatric cases. Many challenges are encountered in the pediatric population during the pre-, intra- and post-operative period. Objectives The aim of this study is to study the demographic profile and respective outcomes of pediatric neurosurgical cases (below 18 years of age). Methods A retrospective study of cases over a period of 1.5 years in the Department of Neurosurgery, Institute of Medical Sciences and Sum Hospital was done. The variables analyzed were age group, sex, diagnosis, elective or emergency, neurological examination, and outcome. Data analysis was done using Version 3.0.2; 2013-09-25 for Statistical Computing (IBM Corporation's SPSS programme, version 27.0, 2020). Literature review was done through the NCBI PubMed, Scopus, Embase, and Google Scholar databases. Quality of life was assessed by the disability-adjusted life years (DALY) score approved by the World Health Organization. Results The majority of the patients had significant improvement in achieving milestones with reduced morbidity and one case of mortality. Conclusion To conclude, we have managed all cases of pediatric age group in a general neurosurgery department with utmost skill and meticulous surgery, with less than 0.1% mortality. In the cases that pertain to low resourced centers, areas, and countries where general neurosurgeons are mandated and obliged to perform pediatric neurosurgical procedures, we general neurosurgeons should take it as a challenge to manage these pediatric cases as our study showed appreciable results although the need for specialized pediatric neurosurgical care cannot be overemphasized