Form Accuracy Analysis of Cylindrical Parts Produced by Rapid Prototyping

Solid Freeform fabrication processes are being considered for creating fit and assembly nature functional parts. It is extremely important that these parts are within allowable dimensional and geometric tolerance. The part accuracy produced by rapid prototyping process is greatly affected by the relative orientation of build and face normal directions. A systematic method is needed to find the reliability of the created product. This paper discusses the work done in this area and the effect of build orientation on the part form accuracy analysis of each specified tolerance like circularity and cylindricity. Feasible build direction that can be used to satisfy those tolerances is identified. It will help process engineer in selecting a build direction that can satisfy a mathematical model of form tolerance.Mechanical Engineerin

Multi Objective Optimisation of Build Orientation for Rapid Prototyping with Fused Deposition Modeling (FDM)

The ability to select the optimal orientation of build up is one of the critical factors since it affects the part surface quality, accuracy, build time and part cost. Various factors to be considered in optimisation of build orientation for FDM are build material, support material, build up time, surface roughness and total cost. Experiments were carried out and results are analysed for varying build orientation for primitive geometries like cylinder. An appropriate weighting factor has been considered for various objective functions depending on the specific requirement of the part while carrying out multi-objective optimisation. These analyses will help process engineers to decide proper build orientation.Mechanical Engineerin

Furosemide induced bullous pemphigoid: a case report

Bullous pemphigoid is an acquired autoimmune disease characterized by subepidermal vesicles and bullae. The etiology is mostly idiopathic with the highest occurrence in elderly patients. However, it is now well-accepted that bp has been triggered by or associated with drug therapy. Over 50 agents have been implicated as a cause of Drug-induced bullous pemphigoid, including diuretics, ace inhibitors, and antibiotics. We present a case of  Bullous pemphigoid in a 75 year old male probably induced by furosemide. A 75 year old male  was admitted to the dermatology department of KIMS hospital, Bengaluru. Presented with multiple tense bullae and vesicles over both upper limbs, forearm and few collapsed bullae and vesicles over the extensor aspect of forearm. Patient had a past history of myocardial infarction and undergone coronary artery bypass grafting for the same and treated with multiple medications. Among the treatment given injection furosemide was the one of the drug, after which he developed lesions and also presented with fluid filled bullae. A diagnosis of bullous pemphigoid was made based on clinical history and was treated with prednisolone, halobetasol and antibiotics. The lesions improved significantly with the above management and patient recovered enough to be discharged from the hospital after 5 days. Severe and serious reactions such as bullous pemphigoid can be caused by used drugs like furosemide

Faster Acquisition Technique for Software-defined GPS Receivers

Acquisition is a most important process and a challenge task for identifying visible satellites, coarse values of carrier frequency, and code phase of the satellite signals in designing software defined Global positioning system (GPS) receiver. This paper presents a new, simple, efficient and faster GPS acquisition via sub-sampled fast Fourier transform (ssFFT). The proposed algorithm exploits the recently developed sparse FFT (or sparse IFFT) that computes in sub-linear time. Further it uses the property of fourier transforms (FT): Aliasing a signal in the time domain corresponds to sub-sampling it in the frequency domain, and vice versa. The ssFFT is an FFT algorithm that computes sub-sampled version of the data by an integer factor ‘d’, and hence, the computational complexity is proportionately reduced by a factor of ‘d log d’ compared to conventional FFT-based algorithms for any length of the input GPS signal. The simulation results show that the proposed ssFFT based GPS acquisition computation is 8.5571 times faster than the conventional FFT-based acquisition computation time. The implementation of this method in an FPGA provides very fast processing of incoming GPS samples that satisfies real-time positioning requirements.Defence Science Journal, Vol. 65, No. 1, January 2015, pp.5-11, DOI:http://dx.doi.org/10.14429/dsj.65.557

An Image Indexing and Region based on Color and Texture

From the previous decade, the enormous rise of the internet has tremendously maximized the amount image databases obtainable. This image gathering such as art works, satellite and medicine is fascinating ever more customers in numerous application domains. The work on image retrieval primarily focuses on efficient and effective relevant images from huge and varied image gatherings which is further becoming more fascinating and exciting. In this paper, the author suggested an effective approach for approximating large-scale retrieval of images through indexing. This approach primarily depends on the visual content of the image segment where the segments are obtained through fuzzy segmentation and are demonstrated through high-frequency sub-band wavelets. Furthermore, owing to the complexity in monitoring large scale information and exponential growth of the processing time, approximate nearest neighbor algorithm is employed to enhance the retrieval speed. Thus, a locality-sensitive hashing using (K-NN Algorithm) is adopted for region-aided indexing technique. Particularly, as the performance of K-NN Approach hinges essentially on the hash function segregating the space, a novel function was uncovered motivated using E8 lattice which could efficiently be amalgamated with multiple probes K-NN Approach and query-adaptive K- NN Approach. To validate the adopted hypothetical selections and to enlighten the efficiency of the suggested approach, a group of experimental results associated to the region-based image retrieval is carried out on the COREL data samples

ADAPTIVE CHANNEL ESTIMATION FOR SUPER-RESOLUTION SPARSE MIMO-OFDM

A multiple-input multiple (MIMO) communication system combined with the orthogonal frequency division multiplexing (OFDM) modulation technique can achieve reliable high data rate transmission over broadband wireless channels. The most important research topic in the wireless communications is the adaptive channel estimation where the channel is rapidly time-varying. In this paper performance analysis of channel estimation through adaptive channel estimation algorithms for estimating channel using different modulation scheme are investigated. a parametric sparse multiple input multiple output (MIMO)-OFDM channel estimation scheme based on the finite rate of innovation (FRI) theory, whereby super-resolution estimates of path delays with arbitrary values can be achieved. Meanwhile, both the spatial and temporal correlations of wireless MIMO channels are exploited to improve the accuracy of the channel estimation. The estimation of channel at pilot frequencies is based on Least Mean Square and Recursive Least Square channel estimation algorithm. I have compared the performances of channel estimation algorithm by measuring bit error rate vs. SNR with BPSK, QPSK 16-PSK and 256- PSK modulation schemes

Optimised control using proportional-integral-derivative controller tuned using internal model control

Time delays are generally unavoidable in the designing frameworks for mechanical and electrical systems and so on.. In both continuous and discrete schemes, the existence of delay creates undesirable impacts on the under-thought which forces exacting constraints on attainable execution.The presence of delay confounds the design structure procedure also. It makes continuous systems boundless dimensional and also extends the readings in discrete systems fundamentally. As the Proportional-Integral-Derivative (PID) controller based on internal model control is essential and strong to address the vulnerabilities and aggravations of the model. But for an real industry process, they are less susceptible to noise than the PID controller.It results in just one tuning parameter which is the time constant of the closed-loop system λ, the internal model control filter factor.It additionally gives a decent answer for the procedure with huge time delays. The design of the PID controller based on the internal model control, with approximation of time delay using Pade’ and Taylor’s series is depicted in this paper. The first order filter used in the design provides good set-point tracking along with disturbance rejection