Filters for digital hearing devices utilize extensively different criteria than those designed for other applications. The device for this application requires miniature size and high performance. In ...fixed coefficient and programmable filter implementations, FIR filtering is constructed using a sequence of multiplications and additions along with delay elements. In this filter, the multipliers are used for coefficient and input multiplication; the adders are used for accumulation and the delay elements are necessary for storing the final accumulated result. The number of delay units, adders and multipliers depends on the number of orders while the size of these elements is based on the word length. The major area of the FIR filter is occupied by Multipliers. Therefore, improving the multiplier optimization will lead to an efficient FIR filter implementation. The multipliers are changed with shift and add circuits for the fixed coefficient FIR filter depending on the number of signed-power-of-two (SPT) terms existing in the fixed coefficient. In this research, the number of SPT terms in filter coefficients is reduced by the differential evolution algorithm. The number of adders required for the common subexpression (CSE) elimination algorithm is further minimized for efficient filter implementation. An area-efficient and high-speed FIR filter is proposed using Distributive arithmetic (DA) and implemented in the Xilinx Spartan3e FPGA environment. The proposed computation sharing multiplier (CSHM) based FIR on DA consumes less area in terms of FPGA slices and reduced delay when compared to the Existing CSHM. The area required for the proposed CSHM is reduced by 34% from the existing CSHM-based FIR Filter. Similarly, the performance of the Proposed FIR filter is increased by 24% more than the existing CSHM Method.
Malocclusion (teeth irregularity) problems are increasing rapidly across the world in all age groups. Malocclusion is treated in orthodontics which is a specialty of dentistry. Orthodontic bracket is ...a component of fixed orthodontic appliance which is used to treat the malocclusion through archwire forces transferred to the tooth. In orthodontic treatment, the preadjusted orthodontic brackets are most widely used compared to the conventional brackets as there is an in-built torque by the angulated slot walls. This study aim to compare the stress distribution in the preadjusted ceramic brackets with and without Stainless steel (SS) metal slot insert along with tooth, alveolar bone and Periodontal Ligament (PDL) contact assembly using Finite Element Analysis (FEA). A preadjusted maxillary right central incisor ceramic orthodontic bracket (with and without metal insert in the slot) are modeled using CATIA software. The solid model of a maxillary right central incisor tooth is obtained from a Computer Tomography (CT) scan using image processing software. The PDL and alveolar bone are modelled using CATIA as per the dimensions. The assembled solid model consists of bracket with and without SS metal slot insert, adhesive layer, tooth, alveolar bone and PDL. The contact between the components and the mesh is created using hypermesh software. The archwire torque is applied as couple inside the bracket slot without using an archwire. The stress distribution in the assembly components are analysed for the applied couple (torque). The stresses induced in the assembly components are compared between ceramic bracket with and without metal slot insert. This in-silico study would help the clinicians to understand the behavior of commonly used ceramic bracket with and without metal slot insert and choose the appropriate bracket for successful treatment.
Accumulation of excess water in Proton exchange membrane fuel cell (PEMFC) is one of the significant technical challenges that needs great attention, since it makes the performance of the fuel cell ...highly unpredictable and unreliable. To address this formidable task, herein by inserting porous inserts in inline and staggered arrangements on the provisions of landing surface of serpentine flow field, we minimize water clogging in gas diffusion layer. Two types of porous inserts namely porous carbon inserts (PCI), porous sponge inserts (PSI) of sizes 2 mm × 2 mm x 2 mm (2 mm porous inserts) and 4 mm × 2 mm x 2 mm (4 mm porous inserts) are tested for water management of PEMFC, and their respective performances are analyzed. The results showed that power density produced by MSI flow field is 9.5% and 11.57% higher than serpentine flow field for 2 mm and 4 mm PCI respectively while the MSS flow field produced 31.81% and 42.56% higher performance in terms of power density compared with serpentine flow field for 2 mm and 4 mm PCI respectively. The MSS flow field with 4 mm PCI produced 27.77% higher power density compared with 2 mm PCI. Using porous sponge insert instead of porous carbon insert increases the power density by 23.33% for 2 mm porous insert and the power density increases 21.73% for 4 mm PSI in MSS flow field. Increasing the size of PSI from 2 mm to 4 mm increases the power density by 26.12% in MSS flow field.
•PEMFC performance has increased by using porous carbon inserts due to better water removal.•Porous sponge inserts have increased performance compared to porous carbon inserts.•Increasing the size of the porous inserts improves the performance of PEMFC.
In flip-chip design, voltage drop reduction in the power ground network has become a challenging problem particularly in the modern Multiple Supply Voltage(MSV) designs. An effective P/G network ...design and floorplanning- based solutions helps to produce a quality power plan in the layout. Hence, this paper proposes an iterative MSV floorplanning methodology that performs modifications in the existing floorplan representation that satisfies the voltage island constraint and produce an IR drop-aware quality layout. Furthermore, the proposed methodology is integrated with commercial tool design flow to analyze the reduction of IR drop in the layout. Two simulation-based experiments are performed in this paper to showcase the significance of this work. Firstly, it presents the simulation results that benchmark the proposed idealogy in non-flip chip designs. Secondly, the presented framework is integrated in flip-chip layouts of FIR design operating with two voltage islands for low power consumption. To understand the ability of the proposed floorplanning approach, the simulation were performed for two different sized P/G mesh structure for various mesh width. Experimental results from both simulations demonstrate that the proposed MSV floorplanning technique is effective in reducing IR drop while optimizing the design for low power dissipation.
The objective of this work was to analyse the stress and deformation in the orthodontic bracket and archwire with different patterns of ligature tying namely full round pattern I (P-I), the figure of ...eight pattern II (P-II) and figure of eight pattern III (P-III) using finite element analysis (FEA). A standard edgewise stainless steel (SS) maxillary right central incisor orthodontic bracket was measured using profile projector. Solid models of the bracket, archwire and three patterns of ligature tie were done. The archwire was modelled and assembled into the bracket slot. The FE model of the assembly was done. Effect of three patterns of ligation on the archwire and bracket was analysed by applying archwire torque as a couple. The stress in the bracket and archwire for the patterns of ligation P-I, P-II and P-III were noted. The maximum deformation of the bracket and archwire for the patterns of ligation P-I, P-II and P-III were obtained. From the analysis, it was concluded that the magnitude of stress in the archwire and the deformation value in the bracket was high in P-I pattern. Ligature pattern P-II developed the least amount of stress and deflection in the bracket and archwire.
Natural convection based passive decay heat removal systems are increasingly being deployed in the newer designs of nuclear reactors with the expectation that they enhance reliability and robustness ...owing to the elimination of reliance on human operators and external electrical power supply. In the absence of demonstrated experience with passive systems, difficulty in testing them on the field and possible range of phenomena which can degrade their performance, in some designs part of the redundant passive circuits are fitted with pumps to alleviate concerns regarding passive system performance. In this study the two types of designs, one with a set of 4 passive thermo-siphon loops and another with electro-magnetic pumps in part or all of the thermo-siphon loops are studied to bring out the reliability aspects. The decay heat removal function failure frequency is analyzed considering, electromagnetic pump integrity, changes in human interaction aspects for the two different configurations. It is observed that the introduction of electromagnetic pumps in two out of four loops increases the decay heat removal function failure frequency by approximately 64%. If electromagnetic pumps are introduced in all the four loops, the decay heat removal function failure frequency increases by an order. The results are highly sensitive to electromagnetic pump reliability. This study indicates that, there is no change in the uncertainty propagated from input parameters to response parameters, there is no significant advantage in terms of flexibility gained for certain operator actions and higher levels of reliability need to be achieved for the electromagnetic pump if it is to be introduced in all the four loops as compared to introduction in only two loops.
•Reliability comparison of a thermo-siphon DHRS of a FBR under natural convection and forced circulation configurations.•Impact of design and critical parametric uncertainty owing to the introduction of EM pumps in the thermo-siphon loops.•Observation of possibility of decrease in reliability due to the introduction of electromagnetic pumps.•Estimation of reliability targets for electromagnetic pumps to maintain passive system reliability level.•Combined treatment of hardware, functional failures and human reliability aspects.
To measure the tie wing deformation of conventional orthodontic bracket during applied archwire torque using finite element analysis (FEA). Maxillary (upper) right central incisor stainless steel ...(SS) conventional orthodontic bracket dimensions were obtained using profile projector. A three-dimension model of the bracket was done. A finite element (FE) model of the bracket was constructed. A SS archwire applied torque was obtained theoretically for the angles of twist from 5° to 40°. Rectangular archwire labial crown torque was applied as a couple in two positions into the bracket slot. Further, the SS bracket profile was considered as ceramic to study the effect of materials. The FE results showed that there was increased bracket tie wing deformation with increasing torque in both the materials. The tie wing deformation varies from 0.24 μm to 12.4 μm and 0.153 μm to 6.65 μm for SS and ceramic respectively. The deformation of occlusal side tie wings was more than the gingival side tie wings. Tie wing deformation leads to the loss of applied torque and might delay the tooth movement. This insilico study visualizes the orthodontic bracket tie wing deformation to clinicians.
BACKGROUND: For the diagnosis of smear-negative pulmonary tuberculosis (PTB), India's Revised National Tuberculosis Control Programme (RNTCP) recommends a course of broad-spectrum antibiotics after ...negative smear on initial sputum examination, followed by repeat sputum examination and
chest X-ray (CXR).OBJECTIVES: 1) To ascertain the proportion of presumptive PTB patients smear-negative on initial sputum examination who completed the diagnostic algorithm, and 2) to investigate barriers to the completion of the algorithm.METHODS: In Karnataka State, India, 256 study
participants were interviewed in 2012 to ascertain the number of days antibiotics had been prescribed and consumed, the number of re-visits to health centre(s), whether repeat sputum examinations had been performed, whether or not CXR had been performed and when, and whether PTB had been diagnosed.
In-depth interviews were conducted with 19 medical officers.RESULTS: The diagnostic algorithm was completed in 13 (5.1%) of 256 participants; three were diagnosed with PTB without completing the algorithm. Most medical officers were unaware of the algorithm, had trained 5-10 years
previously, prescribed antibiotics for <10 days and advised CXR without repeat sputum examination, irrespective of the number of days of antibiotic treatment. Other main reasons for non-completion of algorithm were patients not returning to the health centres and a proportion switching
to the private sector.CONCLUSION: Refresher training courses, raising patient awareness and active follow-up of patients to complete the algorithm are suggested.
SETTING: A South Indian district providing anti-tuberculosis services through the Revised National TB Control Programme (RNTCP) and private health care facilities.OBJECTIVE: To ascertain the profile ...of tuberculosis (TB) patients diagnosed and/or treated in private health care facilities.METHODS:
Data on TB cases diagnosed and/or treated in all clinical departments of the medical college, 83 nursing homes and RNTCP health care facilities were collected prospectively.RESULTS: About 83% of new TB cases recorded in the private medical college, 47% in nursing homes and 24.5% in RNTCP
TB registers were extra-pulmonary. The proportion of retreatment cases was respectively 5.5%, 9.6% and 19.8%. The proportion of males and those in the economically productive age group were similar in the three data sources. About 94% of cases diagnosed in the medical college and 55% in nursing
homes were registered for treatment under the RNTCP. About 11% of the smear-positive patients diagnosed in RNTCP were initial defaulters.CONCLUSION: The proportion of extra-pulmonary cases was higher in the medical college and nursing homes and that of retreatment cases was lower than
in the RNTCP.
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