Implementation of JPEG compression and motion estimation on FPGA hardware

A hardware implementation of JPEG allows for real-time compression in data intensivve applications, such as high speed scanning, medical imaging and satellite image transmission. Implementation options include dedicated DSP or media processors, FPGA boards, and ASICs. Factors that affect the choice of platform selection involve cost, speed, memory, size, power consumption, and case of reconfiguration. The proposed hardware solution is based on a Very high speed integrated circuit Hardware Description Language (VHDL) implememtation of the codec with prefered realization using an FPGA board due to speed, cost and flexibility factors; The VHDL language is commonly used to model hardware impletations from a top down perspective. The VHDL code may be simulated to correct mistakes and subsequently synthesized into hardware using a synthesis tool, such as the xilinx ise suite. The same VHDL code may be synthesized into a number of sifferent hardware architetcures based on constraints given. For example speed was the major constraint when synthesizing the pipeline of jpeg encoding and decoding, while chip area and power consumption were primary constraints when synthesizing the on-die memory because of large area. Thus, there is a trade off between area and speed in logic synthesis

An analysis of the practical DPG method

In this work we give a complete error analysis of the Discontinuous Petrov Galerkin (DPG) method, accounting for all the approximations made in its practical implementation. Specifically, we consider the DPG method that uses a trial space consisting of polynomials of degree $p$ on each mesh element. Earlier works showed that there is a "trial-to-test" operator $T$, which when applied to the trial space, defines a test space that guarantees stability. In DPG formulations, this operator $T$ is local: it can be applied element-by-element. However, an infinite dimensional problem on each mesh element needed to be solved to apply $T$. In practical computations, $T$ is approximated using polynomials of some degree $r > p$ on each mesh element. We show that this approximation maintains optimal convergence rates, provided that $r\ge p+N$, where $N$ is the space dimension (two or more), for the Laplace equation. We also prove a similar result for the DPG method for linear elasticity. Remarks on the conditioning of the stiffness matrix in DPG methods are also included.Comment: Mathematics of Computation, 201

EPIDEMIOLOGICAL STUDY ON HEAD AND NECK MALIGNANCIES - A STUDY OF 150 CASES

OBJECTIVE: In the present study we investigate the head and Neck Malignancy cases presenting to the ENT department of our Hospital, and analyze the same to give inputs as to the incidence of head and neck malignancies, the symptoms and stage of presentation, lifestyle and habits as contributory risk factors, identify ENT primary in neck secondaries, histopathological types and selection of best treatment.METHODS: Prospective analysis of 150 patients with newly diagnosed malignancies of nasopharynx, oropharynx, larynx, hypopharynx and ear.RESULTS: Most malignancies are common in patients greater than 40 years of age. 88% of cancer occur in males. Oropharynx cancer is the most common cancer in our study, with the commonest subsite as base of tongue. Supraglottic and pyriform fossa tumours are the commonest tumour in laryngeal and hypopharyngeal cancers  respectively. The most common presentation is dysphagia. Synergistic effect of smoking and alcohol is seen in 50% of patients. Most of the cases were seen in stage III and IV except glottis cancer which is predominantly seen in stage I, almost all cases were squamous cell carcinoma.CONCLUSION:The results of our study were in conformity with other similar studies. In larynx, Supraglottic was more common as opposed to glottis in certain western studies. Analysis of various factors helps in early diagnosis and management.KEYWORDS:Cancer, Head and Neck Malignancy, Larynx, pharynx, Nasopharynx, Neck secondaries.

Stall force of a cargo driven by N interacting motor proteins

We study a generic one-dimensional model for an intracellular cargo driven by N motor proteins against an external applied force. The model includes motor-cargo and motor-motor interactions. The cargo motion is described by an over-damped Langevin equation, while motor dynamics is specified by hopping rates which follow a local detailed balance condition with respect to change in energy per hopping event. Based on this model, we show that the stall force, the mean external force corresponding to zero mean cargo velocity, is completely independent of the details of the interactions and is, therefore, always equal to the sum of the stall forces of the individual motors. This exact result is arrived on the basis of a simple assumption: the (macroscopic) state of stall of the cargo is analogous to a state of thermodynamic equilibrium, and is characterized by vanishing net probability current between any two microstates, with the latter specified by motor positions relative to the cargo. The corresponding probability distribution of the microstates under stall is also determined. These predictions are in complete agreement with numerical simulations, carried out using specific forms of interaction potentials.Comment: Accepted in Europhysics Letter