Multi Cost Function Fuzzy Stereo Matching Algorithm for Object Detection and Robot Motion Control

Stereo matching algorithms work with multiple images of a scene, taken from two viewpoints, to generate depth information. Authors usually use a single matching function to generate similarity between corresponding regions in the images. In the present research, the authors have considered a combination of multiple data costs for disparity generation. Disparity maps generated from stereo images tend to have noisy sections. The presented research work is related to a methodology to refine such disparity maps such that they can be further processed to detect obstacle regions.  A novel entropy based selective refinement (ESR) technique is proposed to refine the initial disparity map. The information from both the left disparity and right disparity maps are used for this refinement technique. For every disparity map, block wise entropy is calculated. The average entropy values of the corresponding positions in the disparity maps are compared. If the variation between these entropy values exceeds a threshold, then the corresponding disparity value is replaced with the mean disparity of the block with lower entropy. The results of this refinement are compared with similar methods and was observed to be better. Furthermore, in this research work, the v-disparity values are used to highlight the road surface in the disparity map. The regions belonging to the sky are removed through HSV based segmentation. The remaining regions which are our ROIs, are refined through a u-disparity area-based technique.  Based on this, the closest obstacles are detected through the use of k-means segmentation.  The segmented regions are further refined through a u-disparity image information-based technique and used as masks to highlight obstacle regions in the disparity maps. This information is used in conjunction with a kalman filter based path planning algorithm to guide a mobile robot from a source location to a destination location while also avoiding any obstacle detected in its path. A stereo camera setup was built and the performance of the algorithm on local real-life images, captured through the cameras, was observed. The evaluation of the proposed methodologies was carried out using real life out door images obtained from KITTI dataset and images with radiometric variations from Middlebury stereo dataset

FORMULATION AND INVESTIGATION OF POLYMERIC MULTIPLE UNIT PELLET SYSTEMS CONSISTING OF SUSTAINED RELEASE GLIMEPIRIDE AND IMMEDIATE RELEASE ATORVASTATIN CALCIUM

Objective: The objective of the present work was to develop novel fixed-dose combinations (FDCs) for improvement of glucose tolerance in type II diabetes mellitus patients associated with dyslipidemia. Methods: Multiple unit pellet systems (MUPSs) consisting of sustained release (SR) glimepiride and immediate release atorvastatin calcium pellets were formulated. The SR glimepiride pellets were prepared using a combination of locust bean gum and gum ghatti/guar gum. Similarly, the immediate release of atorvastatin calcium pellets was prepared using locust bean gum suspension as a binder. Results: The formulated pellets were characterized using Fourier transform infrared spectroscopy (FTIR) and Differential scanning calorimetry (DSC). Further, surface morphology of the formulated pellets was done by scanning electron microscopy (SEM). FT-IR and DSC studies suggested that there were no chemical interactions between the drug and natural polymers. SEM studies revealed that formulated pellets were in spherical shape. Based on in vitro evaluation, the SR glimepiride formulation developed using a combination of 2% locust bean gum and 2.5% gum ghatti polymers sustained the release of the drug up to 12 h. Similarly, the immediate release atorvastatin calcium formulation containing 1% w/w locust bean gum suspension as a binder and 7% croscarmellose sodium showed fast disintegration of pellets. The in vivo studies in albino Wistar rat revealed that there was an improvement in bioavailability of the drugs. Stability studies showed that there were no significant changes in the drug content and physical appearance of the prepared SR glimepiride and immediate release atorvastatin pellet formulations. Conclusion: Thus, the formulated FDC as MUPS can be used as an alternative approach for treating diabetes mellitus-induced dyslipidemia

Experimental and numerical investigation of an air-to-water heat pipe-based heat exchanger

An experimental and analytical investigation was conducted on an air-to-water heat exchanger equipped with six wickless heat pipes (thermosyphons) charged with water as the working fluid. The flow pattern consisted of a double pass on the evaporator and condenser sections. The six thermosyphons were all made from carbon steel, measured 2m in length and were installed in a staggered arrangement. The objectives of the reported experimental investigation were to analyse the effect of multiple air passes at different air inlet temperatures (100 to 250°C) and air mass flow rates (0.05 to 0.14kg/s) on the thermal performance of the heat exchanger unit including the heat pipes. The results were compared with a CFD model that assumed the heat pipes were solid rods with a constant conductivity. The conductivity of the pipes was extracted from modifications of correlations available in the literature based around the theory of Thermal Resistance. The results proved to be very accurate within 10% of the experimental values

Characterisation of ground thermal and thermo-mechanical behaviour for shallow geothermal energy applications

Increasing use of the ground as a thermal reservoir is expected in the near future. Shallow geothermal energy (SGE) systems have proved to be sustainable alternative solutions for buildings and infrastructure conditioning in many areas across the globe in the past decades. Recently novel solutions, including energy geostructures, where SGE systems are coupled with foundation heat exchangers, have also been developed. The performance of these systems is dependent on a series of factors, among which the thermal properties of the soil play one of major roles. The purpose of this paper is to present, in an integrated manner, the main methods and procedures to assess ground thermal properties for SGE systems and to carry out a critical review of the methods. In particular, laboratory testing through either steady-state or transient methods are discussed and a new synthesis comparing results for different techniques is presented. In-situ testing including all variations of the thermal response test is presented in detail, including a first comparison between new and traditional approaches. The issue of different scales between laboratory and in-situ measurements is then analysed in detail. Finally, thermo-hydro-mechanical behaviour of soil is introduced and discussed. These coupled processes are important for confirming the structural integrity of energy geostructures, but routine methods for parameter determination are still lacking

Towards Excellence...How to Study: A Guide book for Students

e-Book available, please log-in on Member Area to access or contact our librarian.Buku ini adalah panduan yang ditujukan untuk siswa dalam menghadapi tantangan studi dengan baik. Ditulis oleh Dr. M. Thirumaleshwar, buku ini berisi kuliah-kuliah yang mengupas tentang psikologi siswa, impian dan ketakutan mereka, tekanan, kecemasan, serta sikap yang tepat dalam belajar di perguruan tinggi. Buku ini menekankan pentingnya sikap yang benar dalam menghadiri kelas, metode belajar yang efektif, persiapan untuk ujian, dan teknik-teknik untuk menulis ujian dengan baik. Selain itu, buku ini juga memberikan wawasan mengenai teknik meningkatkan daya ingat dan mengatasi stres dalam belajar. Bagian akhir buku ini berisi kutipan-kutipan inspiratif dari para santo dan tokoh terkenal sepanjang sejarah.71 p. ; 23 cm

Heat balance analysis of single stage Gifford-McMahon cycle cryorefrigerator

A heat balance analysis of single stage Gifford-McMahon cycle cryorefrigerator is presented. Ideal refrigeration, actual refrigeration, net refrigeration and the various losses are tabulated. It is observed that pressure-volume losses account for a major fraction of the total losses

Exergy analysis of a Gifford-McMahon cycle cryorefrigerator

Exergy analysis of a Gifford-McMahon cycle refrigerator is presented. Exergy losses occurring in various components are considered and the exergy balance is shown in tabular form. It is observed that the major losses occur in the compressor and at the cold end

Spool valve mechanism used in a 20 K Gifford-McMahon cycle cryorefrigerator and its effect on the P-V diagram

The design and fabrication of a spool valve for a two-stage Gifford-McMahon cycle cryorefrigerator is described. The effect of this valve on the P-V diagram and practical methods of reducing the P-V degradation are also discussed